Pharmaceuticals and Hormones in the Environment

EPA Science Inventory

Some of the earliest initial reports from Europe and the United States demonstrated that a variety of pharmaceuticals and hormones could be found in surface waters, source waters, drinking water, and influents and effluents from wastewater treatment plants (WWTPs). It is unknown...

New insight into California’s drought through open data

USGS Publications Warehouse

Read, Emily K.; Bucknell, Mary; Hines, Megan K.; Kreft, James M.; Lucido, Jessica M.; Read, Jordan S.; Schroedl, Carl; Sibley, David M.; Stephan, Shirley; Suftin, Ivan; Thongsavanh, Phethala; Van Den Hoek, Jamon; Walker, Jordan I.; Wernimont, Martin R; Winslow, Luke A.; Yan, Andrew N.

2015-01-01

Historically unprecedented drought in California has brought water issues to the forefront of the nation’s attention. Crucial investigations that concern water policy, management, and research, in turn, require extensive information about the quality and quantity of California’s water. Unfortunately, key sources of pertinent data are unevenly distributed and frequently hard to find. Thankfully, the vital importance of integrating water data across federal, state, and tribal, academic, and private entities, has recently been recognized and addressed through federal initiatives such as the Climate Data Initiative of President Obama’s Climate Action Plan and the Advisory Committee on Water Information’sOpen Water Data Initiative. Here, we demonstrate an application of integrated open water data, visualized and made available online using open source software, for the purpose of exploring the impact of the current California drought. Our collaborative approach and technical tools enabled a rapid, distributed development process. Many positive outcomes have resulted: the application received recognition within and outside of the Federal Government, inspired others to visualize open water data, spurred new collaborations for our group, and strengthened the collaborative relationships within the team of developers. In this article, we describe the technical tools and collaborative process that enabled the success of the application. 

Access to Safe Water in Rural Artibonite, Haiti 16 Months after the Onset of the Cholera Epidemic

PubMed Central

Patrick, Molly; Berendes, David; Murphy, Jennifer; Bertrand, Fabienne; Husain, Farah; Handzel, Thomas

2013-01-01

Haiti has the lowest improved water and sanitation coverage in the Western Hemisphere and is suffering from the largest cholera epidemic on record. In May of 2012, an assessment was conducted in rural areas of the Artibonite Department to describe the type and quality of water sources and determine knowledge, access, and use of household water treatment products to inform future programs. It was conducted after emergency response was scaled back but before longer-term water, sanitation, and hygiene activities were initiated. The household survey and source water quality analysis documented low access to safe water, with only 42.3% of households using an improved drinking water source. One-half (50.9%) of the improved water sources tested positive for Escherichia coli. Of households with water to test, 12.7% had positive chlorine residual. The assessment reinforces the identified need for major investments in safe water and sanitation infrastructure and the importance of household water treatment to improve access to safe water in the near term. PMID:24106191

40 CFR 63.401 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., ventilation, or air conditioning system. Initial startup means the initiation of recirculation water flow... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for...

Practices that Prevent the Formation of Cyanobacterial Blooms in Water Resources and remove Cyanotoxins during Physical Treatment of Drinking Water

EPA Science Inventory

This book chapter presents findings of different studies on the prevention and elimination of cyanobacterial blooms in raw water resources as well as the removal of cyanotoxins during water treatment with physical processes. Initially,treatments that can be applied at the source ...

Army Net Zero Installation Initiative and Cost Benefit Analysis Activity

DTIC Science & Technology

2011-10-31

freshwater resources and returns water back to the same watershed so not to deplete the groundwater and surface water resources of that... freshwater resources & returns water back to the same watershed so not to deplete the groundwater & surface water resources of that region in quantity...Goals: Reduce freshwater demand through water efficiency & conservation Access/develop alternate water sources to offset freshwater demand Develop

[Arsenic levels in drinking water supplies from underground sources in the community of Madrid].

PubMed

Aragonés Sanz, N; Palacios Diez, M; Avello de Miguel, A; Gómez Rodríguez, P; Martínez Cortés, M; Rodríguez Bernabeu, M J

2001-01-01

In 1998, arsenic concentrations of more than 50 micrograms/l were detected in some drinking water supplies from underground sources in the Autonomous Community of Madrid, which is the maximum permissible concentration for drinking water in Spain. These two facts have meant the getting under way of a specific plan for monitoring arsenic in the drinking water in the Autonomous Community of Madrid. The results of the first two sampling processes conducted in the arsenic level monitoring plan set out are presented. In the initial phase, water samples from 353 water supplies comprised within the census of the Public Health Administration of the Autonomous Community of Madrid were analyzed. A water supply risk classification was made based on these initial results. In a second phase, six months later, the analyses were repeated on those 35 water supplies which were considered to possibly pose a risk to public health. Seventy-four percent (74%) of the water supplies studied in the initial phase were revealed to have an arsenic concentration of less than 10 micrograms/l, 22.6% containing levels of 10 micrograms/l-50 micrograms/l, and 3.7% over 50 micrograms/l. Most of the water supplies showing arsenic levels of more than 10 micrograms/l are located in the same geographical area. In the second sampling process (six months later), the 35 water supplies classified as posing a risk were included. Twenty-six (26) of these supplies were revealed to have the same arsenic level ((10-50 micrograms/l), and nine changed category, six of which had less than 10 micrograms/l and three more than 50 micrograms/l. In the Autonomous Community of Madrid, less than 2% of the population drinks water coming from supplies which are from underground sources. The regular water quality monitoring conducted by the Public Health Administration has led to detecting the presence of more than 50 micrograms/l of arsenic in sixteen drinking water supplies from underground sources, which is the maximum permissible level under the laws currently in force in Spain. Measures have been taken to prevent water from being used from these water supplies. Around 20% of the water supplies studies must take measures in the near future to lower the arsenic concentration to below 10 micrograms/l when the water directive which is currently in the process of being written into Spanish law enters into effect.

Pesticides and their breakdown products in Lake Waxahachie, Texas, and in finished drinking water from the lake

USGS Publications Warehouse

Ging, Patricia B.

2002-01-01

Since 1991, the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program has collected pesticide data from streams and aquifers throughout the Nation (Gilliom and others, 1995). However, little published information on pesticides in public drinking water is available. The NAWQA Program usually collects data on the sources of drinking water but not on the finished drinking water. Therefore, the U.S. Environmental Protection Agency (USEPA), in conjunction with the NAWQA Program, has initiated a nationwide pilot project to collect information on concentrations of pesticides and their breakdown products in finished drinking water, in source waters such as reservoirs, and in the basins that contribute water to the reservoirs. The pilot project was designed to collect water samples from finished drinking-water supplies and the associated source water from selected reservoirs that receive runoff from a variety of land uses. Lake Waxahachie, in Ellis County in north-central Texas, was chosen to represent a reservoir receiving water that includes runoff from cotton cropland. This fact sheet presents the results of pesticide sampling of source water from Lake Waxahachie and in finished drinking water from the lake. Analyses are compared to indicate differences in pesticide detections and concentrations between lake water and finished drinking water.

[170 years of struggle of the Viennese physicians for hygienically safe drinking water].

PubMed

Flamm, Heinz

2010-04-01

Discussions in the Society of Physicians in Vienna about the connection between water contamination and typhoid outbreaks began in 1838. The basis of the water supply at that time was house wells partly drawing contaminated ground water and for a limited area the Kaiser-Ferdinand-Pipeline was useful. After many investigations on quantities and qualities of possible water sources and controversial discussions between Viennese politicians and the Society of Physicians, the latter strictly turned down the usage of surface water. In October 1865 the Society demanded that the source Kaiserbrunn in the Höllental and two other sources nearby in the Limestone Alps should be used for the Viennese water supply. After initial opposition in the municipal council and an outbreak of cholera in Vienna, the erection of the 1st Viennese Mountain-source Water Pipeline was started and the Pipeline was opened in 1873. Because of its insufficient quantity of water for the growing town the Society of Physicians became active again, supported by the Institute of hygiene founded in 1875. This resulted in the erection of the 2nd Viennese Mountain-source Water Pipeline, which was opened in 1910. A threat which had to be met were repeated plans for tourist developments.

What Hayabusa2 Will Find at Asteroid Ryugu, and What It Will Reveal About the Source of Earth's Water

NASA Technical Reports Server (NTRS)

Zolensky, Michael; Martinez, James E.

2017-01-01

Water-rich carbonaceous chondrites contain evidence of aqueous alteration in the early solar system. To see this one must look carefully at the meteorites, and see past the later alteration which has generally obscured mineral textures. We suggest that these materials will dominate, be detectable, and be sampled on the surfaces of C-class asteroids, initially by the Hayabusa2 spacecraft. Thus, hydrous samples returned by this mission will help to reveal the source of water on earth.

National survey of MTBE and other VOCs in community drinking-water sources

USGS Publications Warehouse

Clawges, Rick M.; Rowe, Barbara L.; Zogorski, John S.

2001-01-01

Methyl tert-butyl ether (MTBE) is a volatile organic compound (VOC) that is added to gasoline either seasonally or year round in many parts of the United States to increase the octane level and to reduce carbon monoxide and ozone levels in the air. The chemical properties and widespread use of MTBE can result in contamination of private and public drinking-water sources. MTBE contamination is a concern in drinking water because of the compound's low taste and odor threshold and potential human-health effects.Because of this concern, a survey was initiated in collaboration with researchers and water suppliers. The purpose of this survey is to provide sound, unbiased, scientific information on the occurrence of MTBE and other VOCs in ground water, reservoirs, and rivers that are sources of drinking water used by communities of various sizes throughout the Nation. This fact sheet presents a general description of the survey.

Seeding hydrate formation in water-saturated sand with dissolved-phase methane obtained from hydrate dissolution: A progress report

USGS Publications Warehouse

Waite, William F.; Osegovic, J.P.; Winters, William J.; Max, M.D.; Mason, David H.

2008-01-01

An isobaric flow loop added to the Gas Hydrate And Sediment Test Laboratory Instrument (GHASTLI) is being investigated as a means of rapidly forming methane hydrate in watersaturated sand from methane dissolved in water. Water circulates through a relatively warm source chamber, dissolving granular methane hydrate that was pre-made from seed ice, then enters a colder hydrate growth chamber where hydrate can precipitate in a water-saturated sand pack. Hydrate dissolution in the source chamber imparts a known methane concentration to the circulating water, and hydrate particles from the source chamber entrained in the circulating water can become nucleation sites to hasten the onset of hydrate formation in the growth chamber. Initial results suggest hydrate grows rapidly near the growth chamber inlet. Techniques for establishing homogeneous hydrate formation throughout the sand pack are being developed.

UTILITY OF SURROGATES FOR MEASURING CRYPTOSPORIDIUM OOCYST INFECTIVITY

EPA Science Inventory

The water industry must assess whether Cryptosporidium oocysts detected in source and finished water are viable and/or infectious. Initial approaches measuring the infectious nature of C. parvum oocysts have focused on in vitro excystation and in vitro vital dye staining. Recen...

UTILITY OF SURROGATES FOR MEASURING CRYPTOSPORIDIUM OOCYSTS INFECTIVITY

EPA Science Inventory

The water industry must assess whether Cryptosporidium oocysts detected in source and finished water are viable and/or infectious. Initial approaches measuring the infectious nature of C. parvum oocysts have focused on in vitro excystation and in vitro vital dye staining. Recen...

Trend analysis of a tropical urban river water quality in Malaysia.

PubMed

Othman, Faridah; M E, Alaa Eldin; Mohamed, Ibrahim

2012-12-01

Rivers play a significant role in providing water resources for human and ecosystem survival and health. Hence, river water quality is an important parameter that must be preserved and monitored. As the state of Selangor and the city of Kuala Lumpur, Malaysia, are undergoing tremendous development, the river is subjected to pollution from point and non-point sources. The water quality of the Klang River basin, one of the most densely populated areas within the region, is significantly degraded due to human activities as well as urbanization. Evaluation of the overall river water quality status is normally represented by a water quality index (WQI), which consists of six parameters, namely dissolved oxygen, biochemical oxygen demand, chemical oxygen demand, suspended solids, ammoniacal nitrogen and pH. The objectives of this study are to assess the water quality status for this tropical, urban river and to establish the WQI trend. Using monthly WQI data from 1997 to 2007, time series were plotted and trend analysis was performed by employing the first-order autocorrelated trend model on the moving average values for every station. The initial and final values of either the moving average or the trend model were used as the estimates of the initial and final WQI at the stations. It was found that Klang River water quality has shown some improvement between 1997 and 2007. Water quality remains good in the upper stream area, which provides vital water sources for water treatment plants in the Klang valley. Meanwhile, the water quality has also improved in other stations. Results of the current study suggest that the present policy on managing river quality in the Klang River has produced encouraging results; the policy should, however, be further improved alongside more vigorous monitoring of pollution discharge from various point sources such as industrial wastewater, municipal sewers, wet markets, sand mining and landfills, as well as non-point sources such as agricultural or urban runoff and commercial activity.

Hydrogen-bond memory and water-skin supersolidity resolving the Mpemba paradox.

PubMed

Zhang, Xi; Huang, Yongli; Ma, Zengsheng; Zhou, Yichun; Zhou, Ji; Zheng, Weitao; Jiang, Qing; Sun, Chang Q

2014-11-14

The Mpemba paradox, that is, hotter water freezes faster than colder water, has baffled thinkers like Francis Bacon, René Descartes, and Aristotle since B.C. 350. However, a commonly accepted understanding or theoretical reproduction of this effect remains challenging. Numerical reproduction of observations, shown herewith, confirms that water skin supersolidity [Zhang et al., Phys. Chem. Chem. Phys., DOI: ] enhances the local thermal diffusivity favoring heat flowing outwardly in the liquid path. Analysis of experimental database reveals that the hydrogen bond (O:H-O) possesses memory to emit energy at a rate depending on its initial storage. Unlike other usual materials that lengthen and soften all bonds when they absorb thermal energy, water performs abnormally under heating to lengthen the O:H nonbond and shorten the H-O covalent bond through inter-oxygen Coulomb coupling [Sun et al., J. Phys. Chem. Lett., 2013, 4, 3238]. Cooling does the opposite to release energy, like releasing a coupled pair of bungees, at a rate of history dependence. Being sensitive to the source volume, skin radiation, and the drain temperature, the Mpemba effect proceeds only in the strictly non-adiabatic 'source-path-drain' cycling system for the heat "emission-conduction-dissipation" dynamics with a relaxation time that drops exponentially with the rise of the initial temperature of the liquid source.

10 CFR 70.39 - Specific licenses for the manufacture or initial transfer of calibration or reference sources.

Code of Federal Regulations, 2013 CFR

2013-01-01

.... The entire radioactive surface of the source shall be wiped with filter paper, moistened with water... shall be wiped with filter paper with the application of moderate finger pressure. Removal of radioactive material from the source shall be determined by measuring the radioactivity on the filter paper or...

10 CFR 70.39 - Specific licenses for the manufacture or initial transfer of calibration or reference sources.

Code of Federal Regulations, 2014 CFR

2014-01-01

.... The entire radioactive surface of the source shall be wiped with filter paper, moistened with water... shall be wiped with filter paper with the application of moderate finger pressure. Removal of radioactive material from the source shall be determined by measuring the radioactivity on the filter paper or...

10 CFR 70.39 - Specific licenses for the manufacture or initial transfer of calibration or reference sources.

Code of Federal Regulations, 2012 CFR

2012-01-01

.... The entire radioactive surface of the source shall be wiped with filter paper, moistened with water... shall be wiped with filter paper with the application of moderate finger pressure. Removal of radioactive material from the source shall be determined by measuring the radioactivity on the filter paper or...

Two different sources of water for the early solar nebula.

PubMed

Kupper, Stefan; Tornow, Carmen; Gast, Philipp

2012-06-01

Water is essential for life. This is a trivial fact but has profound implications since the forming of life on the early Earth required water. The sources of water and the related amount of delivery depend not only on the conditions on the early Earth itself but also on the evolutionary history of the solar system. Thus we ask where and when water formed in the solar nebula-the precursor of the solar system. In this paper we explore the chemical mechanics for water formation and its expected abundance. This is achieved by studying the parental cloud core of the solar nebula and its gravitational collapse. We have identified two different sources of water for the region of Earth's accretion. The first being the sublimation of the icy mantles of dust grains formed in the parental cloud. The second source is located in the inner region of the collapsing cloud core - the so-called hot corino with a temperature of several hundred Kelvin. There, water is produced efficiently in the gas phase by reactions between neutral molecules. Additionally, we analyse the dependence of the production of water on the initial abundance ratio between carbon and oxygen.

IN-STREAM CONTINUOUS SOURCE WATER QUALITY MONITORING SYSTEM

EPA Science Inventory

Abstract:

The U.S. Environmental Protection Agency (EPA) Office of Research and Development (ORD) provided the Ohio River Valley Water Sanitation Commission (ORSANCO) with a grant as part of the Advanced Measurement Initiative (AMI). The objective of AMI is to provide an ...

Antimicrobial Effect of An Essential Oil Blend on Surface-attached Salmonella on Polyvinyl Chloride

USDA-ARS?s Scientific Manuscript database

The majority of drinking water lines for broilers are made of polyvinyl chloride (PVC) and surface attachment of Salmonella on the inner surface of water lines can be the initial stage of biofilm development. These biofilms can be the source of Salmonella infection in water lines and are known to re...

Man-made organic compounds in source water of nine community water systems that withdraw from streams, 2002-05

USGS Publications Warehouse

Kingsbury, James A.; Delzer, Gregory C.; Hamilton, Pixie A.

2008-01-01

Initial findings from a national study by the National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey (USGS) characterize the occurrence of about 250 anthropogenic organic compounds in source water (defined as water collected at a surface-water intake prior to water treatment) at nine community water systems in nine States in the Nation. The organic compounds analyzed in this study are primarily man-made and include pesticides, solvents, gasoline hydrocarbons, personal-care and domestic-use products, disinfection by-products, and manufacturing additives. The study also describes and compares the occurrence of selected compounds detected in source water with their occurrence in finished water, which is defined as water that has passed through treatment processes but prior to distribution. This fact sheet summarizes major findings and implications of the study and serves as a companion product to two USGS reports that present more detailed and technical information for the nine systems studied during 2002-05 (Carter and others, 2007; Kingsbury and others, 2008).

Characterization of the relationship between ceramic pot filter water production and turbidity in source water.

PubMed

Salvinelli, Carlo; Elmore, A Curt; Reidmeyer, Mary R; Drake, K David; Ahmad, Khaldoun I

2016-11-01

Ceramic pot filters represent a common and effective household water treatment technology in developing countries, but factors impacting water production rate are not well-known. Turbidity of source water may be principal indicator in characterizing the filter's lifetime in terms of water production capacity. A flow rate study was conducted by creating four controlled scenarios with different turbidities, and influent and effluent water samples were tested for total suspended solids and particle size distribution. A relationship between average flow rate and turbidity was identified with a negative linear trend of 50 mLh -1 /NTU. Also, a positive linear relationship was found between the initial flow rate of the filters and average flow rate calculated over the 23 day life of the experiment. Therefore, it was possible to establish a method to estimate the average flow rate given the initial flow rate and the turbidity in the influent water source, and to back calculate the maximum average turbidity that would need to be maintained in order to achieve a specific average flow rate. However, long-term investigations should be conducted to assess how these relationships change over the expected CPF lifetime. CPFs rejected fine suspended particles (below 75 μm), especially particles with diameters between 0.375 μm and 10 μm. The results confirmed that ceramic pot filters are able to effectively reduce turbidity, but pretreatment of influent water should be performed to avoid premature failure. Copyright © 2016 Elsevier Ltd. All rights reserved.

Small-scale experimental study of vaporization flux of liquid nitrogen released on water.

PubMed

Gopalaswami, Nirupama; Olewski, Tomasz; Véchot, Luc N; Mannan, M Sam

2015-10-30

A small-scale experimental study was conducted using liquid nitrogen to investigate the convective heat transfer behavior of cryogenic liquids released on water. The experiment was performed by spilling five different amounts of liquid nitrogen at different release rates and initial water temperatures. The vaporization mass fluxes of liquid nitrogen were determined directly from the mass loss measured during the experiment. A variation of initial vaporization fluxes and a subsequent shift in heat transfer mechanism were observed with changes in initial water temperature. The initial vaporization fluxes were directly dependent on the liquid nitrogen spill rate. The heat flux from water to liquid nitrogen determined from experimental data was validated with two theoretical correlations for convective boiling. It was also observed from validation with correlations that liquid nitrogen was found to be predominantly in the film boiling regime. The substantial results provide a suitable procedure for predicting the heat flux from water to cryogenic liquids that is required for source term modeling. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparative Persistence of Subgroups of F-Specific RNA Phages in River Water

PubMed Central

Yang, Yongheng

2013-01-01

F-specific (F+) RNA phages are widely used as indicators for the presence of fecal contamination and/or enteric viruses in water, and identifying subgroups of F+ RNA phages provides an approach for microbial source tracking. Different survival characteristics of the F+ RNA phage subgroups result in a misinterpretation of their original proportion in water, thus giving misleading information when they are used for microbial source tracking. This study investigated the comparative persistence of subgroups of F+ RNA phages in river water under different conditions. Results suggested that temperature and pH are the major factors affecting the persistence of F+ RNA phages in river water, and organic substances promote phage survival. The comparative persistence patterns of subgroups of F+ RNA phages varied and may bias extrapolation of their initial proportions in surface water. Thus, the characteristics of water should be taken into consideration and the results should be carefully interpreted when F+ RNA phages are used for microbial source tracking. PMID:23686274

Hydrologic reconnaissance evaluation of the Federal Capital Territory and surrounding areas, Nigeria

USGS Publications Warehouse

Peterson, L.R.; Meyer, Gerald

1977-01-01

Initial moderate water requirements of the new Federal Capital Territory in Central Nigeria are available from the two large rivers, the Niger and Benue, from the smaller Gurara River, and possibly from several smaller streams. Ground water in the southwestern part of the Territory and in adjacent areas along the Niger River is also a potential source. The Niger and Benue Rivers are obvious sources of major supply for eventual large demands, and the Gurara River and sedimentary aquifers also may have that potential. Available data are sparse and highly inadequate for satisfactory design of assessment, development, and management plans for the Territory. Initiation of systematic investigation and collection of data at an early date is recommended. (Woodard-USGS)

Photolytic AND Catalytic Destruction of Organic Waste Water Pollutants

NASA Astrophysics Data System (ADS)

Torosyan, V. F.; Torosyan, E. S.; Kryuchkova, S. O.; Gromov, V. E.

2017-01-01

The system: water supply source - potable and industrial water - wastewater - sewage treatment - water supply source is necessary for water supply and efficient utilization of water resources. Up-to-date technologies of waste water biological treatment require for special microorganisms, which are technologically complex and expensive but unable to solve all the problems. Application of photolytic and catalytically-oxidizing destruction is quite promising. However, the most reagents are strong oxidizers in catalytic oxidation of organic substances and can initiate toxic substance generation. Methodic and scientific approaches to assess bread making industry influence on the environment have been developed in this paper in order to support forecasting and taking technological decisions concerning reduction of this influence. Destructive methods have been tested: ultra violet irradiation and catalytic oxidation for extraction of organic compounds from waste water by natural reagents.

Assessment of hydrogeologic terrains, well-construction characteristics, groundwater hydraulics, and water-quality and microbial data for determination of surface-water-influenced groundwater supplies in West Virginia

USGS Publications Warehouse

Kozar, Mark D.; Paybins, Katherine S.

2016-08-30

Groundwater public-supply systems in areas of high intrinsic susceptibility and with a large number of potential contaminant sources within the recharge or source-water-protection area of individual wells or well fields are potentially vulnerable to contamination and probably warrant further evaluation as potential SWIGS. However, measures can be taken to educate the local population and initiate safety protocols and protective strategies to appropriately manage contaminant sources to prevent release of contaminants to the aquifer, therefore, reducing vulnerability of these systems to contamination. However, each public groundwater supply source needs to be assessed on an individual basis. Data presented in this report can be used to categorize and prioritize wells and springs that have a high potential for intrinsic susceptibility or vulnerability to contamination.

Fracturing of porous rock induced by fluid injection

NASA Astrophysics Data System (ADS)

Stanchits, Sergei; Mayr, Sibylle; Shapiro, Serge; Dresen, Georg

2011-04-01

We monitored acoustic emission (AE) activity and brittle failure initiated by water injection into initially dry critically stressed cylindrical specimens of Flechtingen sandstone of 50 mm diameter and 105-125 mm length. Samples were first loaded in axial direction at 40-50 MPa confining pressure at dry conditions close to peak stress. Subsequently distilled water was injected either at the bottom of specimen or via a central borehole at pore pressures of 5-30 MPa. Water injection into stressed porous sandstone induced a cloud of AE events located close to the migrating water front. Water injection was monitored by periodic ultrasonic velocity measurements across the sample. Propagation of the induced cloud of AE was faster in the direction parallel to bedding than normal to it, indicating permeability anisotropy. Water injection was associated with significant AE activity demonstrating increased contribution of tensile source type. Brittle failure was accompanied by increased contribution of shear and pore collapse source types. At a critical pore pressure, a brittle fault nucleated from a cloud of induced AE events in all samples. Microstructural analysis of fractured samples shows excellent agreement between location of AE hypocenters and macroscopic faults.

Four phases of the Flint Water Crisis: Evidence from blood lead levels in children.

PubMed

Zahran, Sammy; McElmurry, Shawn P; Sadler, Richard C

2017-08-01

The Flint Water Crisis (FWC) is divisible into four phases of child water-lead exposure risk: Phase A) before the switch in water source to the Flint River (our baseline); Phase B) after the switch in water source, but before boil water advisories; Phase C) after boil water advisories, but before the switch back to the baseline water source of the Detroit Water and Sewerage Department (DWSD); and Phase D) after the switch back to DWSD. The objective of this work is to estimate water-lead attributable movements in child blood lead levels (BLLs) that correspond with the four phases in the FWC. With over 21,000 geo-referenced and time-stamped blood lead samples from children in Genesee County drawn from January 01, 2013 to July 19, 2016, we develop a series of quasi-experimental models to identify the causal effect of water-lead exposure on child BLLs in Flint. We find that the switch in water source (transitioning from phase A to B) caused mean BLLs to increase by about 0.5μg/dL, and increased the likelihood of a child presenting with a BLL ≥ 5μg/dL by a factor of 1.91-3.50, implying an additional 561 children exceeding 5μg/dL. We conservatively estimate cohort social costs (through lost earnings alone) of this increase in water-lead exposed children at $65 million, contrasted with expected annual savings of $2 million from switching water source. On the switch from Phase B to C, we find BLLs decreased about 50% from their initial rise following boil water advisories and subsequent water avoidance behaviors by households. Finally, the return to the baseline source water (Phase D) returned child BLLs to pre-FWC levels further implicating water-lead exposure as a causal source of child BLLs throughout the FWC. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

A risk assessment of water salinization during the initial impounding period of a proposed reservoir in Tianjin, China.

PubMed

Zhu, Liqin; Jiang, Cuiling; Wang, Youheng; Peng, Yanmei; Zhang, Peng

2013-09-01

Water salinization of coastal reservoirs seriously threatens the safety of their water supply. To elucidate the mechanism of salinization and to quantitatively analyze the risk in the initial period of the impoundment of a proposed reservoir in Tianjin Binhai New Area, laboratory and field simulation experiments were implemented and integrated with the actual operation of Beitang Reservoir, which is located in the same region and has been operational for many years. The results suggested that water salinization of the proposed reservoir was mainly governed by soil saline release, evaporation and leakage. Saline release was the prevailing factor in the earlier stage of the impoundment, then the evaporation and leakage effects gradually became notable over time. By referring to the actual case of Beitang Reservoir, it was predicted that the chloride ion (Cl(-)) concentration of the water during the initial impounding period of the proposed reservoir would exceed the standard for quality of drinking water from surface water sources (250 mg L(-1)), and that the proposed reservoir had a high risk of water salinization.

Metering gun for dispensing precisely measured charges of fluid

NASA Technical Reports Server (NTRS)

Cook, T. A.; Scheibe, H. (Inventor)

1974-01-01

A cyclically operable fluid dispenser for use in dispensing precisely measured charges of potable water aboard spacecraft is described. The dispenser is characterized by (1) a sealed housing adapted to be held within a crewman's palm and coupled with a pressurized source of potable water; (2) a dispensing jet projected from the housing and configured to be received within a crewman's lips; (3) an expansible measuring chamber for measuring charges of drinking water received from the source; (4) and a dispenser actuator including a lever extended from the housing to be digitated for initiating operational cycles, whereby precisely measured charges of potable water selectively are delivered for drinking purposes in a weightless environment.

Fiscal year 1988 program report: Pennsylvania Center for Water Resources Research

DOE Office of Scientific and Technical Information (OSTI.GOV)

McDonnell, A.J.

1989-08-01

Three projects and a program of technology transfer were conducted under the Pennsylvania Fiscal Year 1988 State Water Resources Research Grants Program (PL 98-242, Sect. 104). In a completed study focused on the protection of water supplies, mature slow sand filters were found to remove 100 percent of Cryptosporidium and Giardia cysts. A site specific study examined the behavior of sedimentary iron and manganese in an acid mine drainage wetland system. A study was initiated to link a comprehensive non-point source model, AGNPS with current GIS technology to enhance the models' utility for evaluating regional water quality problems related tomore » non-point source agricultural pollution.« less

Calculation of intercepted runoff depth based on stormwater quality and environmental capacity of receiving waters for initial stormwater pollution management.

PubMed

Peng, Hai-Qin; Liu, Yan; Gao, Xue-Long; Wang, Hong-Wu; Chen, Yi; Cai, Hui-Yi

2017-11-01

While point source pollutions have gradually been controlled in recent years, the non-point source pollution problem has become increasingly prominent. The receiving waters are frequently polluted by the initial stormwater from the separate stormwater system and the wastewater from sewage pipes through stormwater pipes. Consequently, calculating the intercepted runoff depth has become a problem that must be resolved immediately for initial stormwater pollution management. The accurate calculation of intercepted runoff depth provides a solid foundation for selecting the appropriate size of intercepting facilities in drainage and interception projects. This study establishes a separate stormwater system for the Yishan Building watershed of Fuzhou City using the InfoWorks Integrated Catchment Management (InfoWorks ICM), which can predict the stormwater flow velocity and the flow of discharge outlet after each rainfall. The intercepted runoff depth is calculated from the stormwater quality and environmental capacity of the receiving waters. The average intercepted runoff depth from six rainfall events is calculated as 4.1 mm based on stormwater quality. The average intercepted runoff depth from six rainfall events is calculated as 4.4 mm based on the environmental capacity of the receiving waters. The intercepted runoff depth differs when calculated from various aspects. The selection of the intercepted runoff depth depends on the goal of water quality control, the self-purification capacity of the water bodies, and other factors of the region.

Bibliography, indices, and data sources of water-related studies, upper Colorado River basin, Colorado and Utah, 1872-1995

USGS Publications Warehouse

Bauch, N.J.; Apodaca, L.E.

1995-01-01

As part of the U.S. Geological Survey's National Water-Quality Assessment Program, current water-quality conditions in the Upper Colorado River Basin in Colorado and Utah are being assessed. This report is an initial effort to identify and compile information on water-related studies previously conducted in the basin and consists of a bibliography, coauthor and subject indices, and sources of available water-related data. Computerized literature searches of scientific data bases were carried out to identify past water-related studies in the basin, and government agencies and private organizations were contacted regarding their knowledge or possession of water-related publications and data. Categories of information in the bibliography include: aquatic biology, climate, energy development, geology, land use, limnology, runoff, salinity, surface- and ground-water hydrology, water chemistry, water quality and quantity, and water use and management. The approximately 1,400 indexed references date from 1872 through February 1995 and include books, journal articles, maps, and reports. In many instances, an abstract has been provided for a given reference. Sources of water-related data in the basin are included in a table.

Development of the water-analysis screening tool used in the initial screening for the Pennsylvania State Water Plan update of 2008

USGS Publications Warehouse

Stuckey, Marla H.

2008-01-01

The Water Resources Planning Act, Act 220 of 2002, requires the Pennsylvania Department of Environmental Protection (PaDEP) to update the State Water Plan by 2008. As part of this update, a water-analysis screening tool (WAST) was developed by the U.S. Geological Survey, in cooperation with the PaDEP, to provide assistance to the state in the identification of critical water-planning areas. The WAST has two primary inputs: net withdrawals and the initial screening criteria. A comprehensive water-use database that includes data from registration, estimation, discharge monitoring reports, mining data, and other sources was developed as input into the WAST. Water use in the following categories was estimated using water-use factors: residential, industrial, commercial, agriculture, and golf courses. A percentage of the 7-day, 10-year low flow is used for the initial screenings using the WAST to identify potential critical water-planning areas. This quantity, or initial screening criteria, is 50 percent of the 7-day, 10-year low flow for most streams. Using a basic water-balance equation, a screening indicator is calculated that indicates the potential influences of net withdrawals on aquatic-resource uses for watersheds generally larger than 15 square miles. Points representing outlets of these watersheds are colored-coded within the WAST to show the screening criteria for each watershed.

Unregulated drinking water initiative for environmental surveillance and public health.

PubMed

Backer, Lorraine C; Tosta, Nancy

2011-03-01

The critical public health need to assess and protect the drinking water used by 37 million Americans requires attention and resources. NCEH, in partnership with states, has begun the process to identify information available on unregulated drinking water sources to improve the availability of data to support decisive public health actions and resource allocation. Far more attention and resources are needed to complete this process.

40 CFR Appendix F to Part 132 - Great Lakes Water Quality Initiative Implementation Procedures

Code of Federal Regulations, 2012 CFR

2012-07-01

... the structure of the aquatic food web and the disequilibrium constant, are different at the site than..., the TMDL shall also indicate the point source effluent flows assumed in the analyses. Mass loading... more proximate sources interact or overlap, the combined effect must be evaluated to ensure that...

40 CFR Appendix F to Part 132 - Great Lakes Water Quality Initiative Implementation Procedures

Code of Federal Regulations, 2014 CFR

2014-07-01

... the structure of the aquatic food web and the disequilibrium constant, are different at the site than..., the TMDL shall also indicate the point source effluent flows assumed in the analyses. Mass loading... more proximate sources interact or overlap, the combined effect must be evaluated to ensure that...

Water and waste water reclamation in a 21st century space colony

NASA Technical Reports Server (NTRS)

Jebens, H. J.; Johnson, R. D.

1977-01-01

The paper presents the results of research on closed-life support systems initiated during a system design study on space colonization and concentrates on the water and waste water components. Metabolic requirements for the 10,000 inhabitants were supplied by an assumed earth-like diet from an intensive agriculture system. Condensed atmospheric moisture provided a source of potable water and a portion of the irrigation water. Waste water was reclaimed by wet oxidation. The dual-water supply required the condensation of 175 kg/person-day of atmospheric water and the processing of 250 kg/person-day of waste water.

LOW-LEVEL EMERGING CONTAMINANTS IN LAKE HAVASU, ARIZONA AND CALIFORNIA AND THEIR ACCESS TO LAKE HAVASU CITY'S DRINKING WATER SUPPLY

EPA Science Inventory

In preparation of a wastewater effluent re-charge and recovery program, involving alluvial fan sediments, the City of Lake Havasu initiated a survey to evaluate possible waterborne sources of emerging contaminants in the water/wastewater distribution cycle. This distribution cyc...

Children's drinking water: parental preferences and implications for fluoride exposure.

PubMed

Sriraman, Natasha K; Patrick, Patricia A; Hutton, Kara; Edwards, Karen S

2009-01-01

The purposes of this study were to: describe children's drinking water sources; determine if any demographic factors are associated with water choice; describe parents' reasons for selecting bottled water; and determine parents' ability to provide enough information about their drinking water for providers to assess children's fluoride exposure. Subjects were parents of children 6 months to 15-years-old. A questionnaire was verbally administered in English or Spanish. Chi-square analyses were used to evaluate associations among study variables. Of 194 parents, 134 (69%) gave their children bottled water either exclusively or with tap water. Bottled water use was not significantly associated with the primary source of tap water, parent's education level, or household income. Reasons for giving children bottled water included: fear of contaminants in tap water; taste and/or smell of tap water; and convenience of bottled water. For parents using bottled water, over 65% did not know the brand's fluoride content. Barriers to an accurate fluoride assessment include frequent bottled water use and parental uncertainty about its fluoride content. By initiating communication with parents and educating them about fluoride sources, health care and dental providers may be able to better evaluate the adequacy of children's fluoride exposure and decide whether fluoride supplementation is necessary.

Water Pollution Prediction in the Three Gorges Reservoir Area and Countermeasures for Sustainable Development of the Water Environment.

PubMed

Li, Yinghui; Huang, Shuaijin; Qu, Xuexin

2017-10-27

The Three Gorges Project was implemented in 1994 to promote sustainable water resource use and development of the water environment in the Three Gorges Reservoir Area (hereafter "Reservoir Area"). However, massive discharge of wastewater along the river threatens these goals; therefore, this study employs a grey prediction model (GM) to predict the annual emissions of primary pollution sources, including industrial wastewater, domestic wastewater, and oily and domestic wastewater from ships, that influence the Three Gorges Reservoir Area water environment. First, we optimize the initial values of a traditional GM (1,1) model, and build a new GM (1,1) model that minimizes the sum of squares of the relative simulation errors. Second, we use the new GM (1,1) model to simulate historical annual emissions data for the four pollution sources and thereby test the effectiveness of the model. Third, we predict the annual emissions of the four pollution sources in the Three Gorges Reservoir Area for a future period. The prediction results reveal the annual emission trends for the major wastewater types, and indicate the primary sources of water pollution in the Three Gorges Reservoir Area. Based on our predictions, we suggest several countermeasures against water pollution and towards the sustainable development of the water environment in the Three Gorges Reservoir Area.

Mercury Release from the Rathburn Mine, Petray Mine, and Bear Valley Saline Springs, Colusa County, California 2004-2006

USGS Publications Warehouse

Slowey, Aaron J.; Rytuba, James J.

2008-01-01

This report summarizes data obtained from field sampling of mine tailings and waste rock at the Rathburn and Petray Mines that was initiated in July 17, 2001 and water and sediment in regional springs and tributaries that drain from the mine area into Bear Creek on December 14, 2004 and February 16 and May 27, 2005. Although it was initially assumed that the mines were the cause of elevated levels of monomethyl Hg measured by the Central Regional Water Quality Control Board in tributaries near their confluence with Bear Creek (Foe and others, unpublished results), it became apparent during this study that ground water springs were also potential sources of Hg. In addition to sampling of springs in May 2005, saline ground water seepage along an unnamed fault on the west side of Bear Valley was sampled on December 13-14, 2006. We did not sample water or sediment in Bear Creek itself during this study. Our results permit a preliminary assessment of mining and natural sources of Hg and associated chemical constituents that could elevate levels of monomethyl Hg in Bear Creek.

Balancing practicality and hydrologic realism: a parsimonious approach for simulating rapid groundwater recharge via unsaturated-zone preferential flow

USGS Publications Warehouse

Mirus, Benjamin B.; Nimmo, J.R.

2013-01-01

The impact of preferential flow on recharge and contaminant transport poses a considerable challenge to water-resources management. Typical hydrologic models require extensive site characterization, but can underestimate fluxes when preferential flow is significant. A recently developed source-responsive model incorporates film-flow theory with conservation of mass to estimate unsaturated-zone preferential fluxes with readily available data. The term source-responsive describes the sensitivity of preferential flow in response to water availability at the source of input. We present the first rigorous tests of a parsimonious formulation for simulating water table fluctuations using two case studies, both in arid regions with thick unsaturated zones of fractured volcanic rock. Diffuse flow theory cannot adequately capture the observed water table responses at both sites; the source-responsive model is a viable alternative. We treat the active area fraction of preferential flow paths as a scaled function of water inputs at the land surface then calibrate the macropore density to fit observed water table rises. Unlike previous applications, we allow the characteristic film-flow velocity to vary, reflecting the lag time between source and deep water table responses. Analysis of model performance and parameter sensitivity for the two case studies underscores the importance of identifying thresholds for initiation of film flow in unsaturated rocks, and suggests that this parsimonious approach is potentially of great practical value.

Anthropogenic organic compounds in source water of selected community water systems that use groundwater, 2002-05

USGS Publications Warehouse

Hopple, Jessica A.; Delzer, Gregory C.; Kingsbury, James A.

2009-01-01

Source water, defined as groundwater collected from a community water system well prior to water treatment, was sampled from 221 wells during October 2002 to July 2005 and analyzed for 258 anthropogenic organic compounds. Most of these compounds are unregulated in drinking water and include pesticides and pesticide degradates, gasoline hydrocarbons, personal-care and domestic-use products, and solvents. The laboratory analytical methods used in the study have detection levels that commonly are 100 to 1,000 times lower than State and Federal standards and guidelines for protecting water quality. Detections of anthropogenic organic compounds do not necessarily indicate a concern to human health but rather help to identify emerging issues and track changes in occurrence and concentrations over time. Less than one-half (120) of the 258 compounds were detected in at least one source-water sample. Chloroform, in 36 percent of samples, was the most commonly detected of the 12 compounds that were in about 10 percent or more of source-water samples. The herbicides atrazine, metolachlor, prometon, and simazine also were among the commonly detected compounds. The commonly detected degradates of atrazine - deethylatrazine and deisopropylatrazine - as well as degradates of acetochlor and alachlor, generally were detected at concentrations similar to or greater than concentrations of the parent herbicide. The compounds perchloroethene, trichloroethene, 1,1,1-trichloroethane, methyl tert-butyl ether, and cis-1,2-dichloroethene also were detected commonly. The most commonly detected compounds in source-water samples generally were among those detected commonly across the country and reported in previous studies by the U.S. Geological Survey's National Water-Quality Assessment Program. Relatively few compounds were detected at concentrations greater than human-health benchmarks, and 84 percent of the concentrations were two or more orders of magnitude less than benchmarks. Five compounds (perchloroethene, trichloroethene, 1,2-dibromoethane, acrylonitrile, and dieldrin) were detected at concentrations greater than their human-health benchmark. The human-health benchmarks used for comparison were U.S. Environmental Protection Agency Maximum Contaminant Levels (MCLs) for regulated compounds and Health-Based Screening Levels developed by the U.S. Geological Survey in collaboration with the U.S. Environmental Protection Agency and other agencies for unregulated compounds. About one-half of all detected compounds do not have human-health benchmarks or adequate toxicity information to evaluate results in a human-health context. Ninety-four source-water and finished-water (water that has passed through all the treatment processes but prior to distribution) sites were sampled at selected community water systems during June 2004 to September 2005. Most of the samples were analyzed for compounds that were detected commonly or at relatively high concentrations during the initial source-water sampling. The majority of the finished-water samples represented water blended with water from one or more other wells. Thirty-four samples were from water systems that did not blend water from sampled wells with water from other wells prior to distribution. The comparison of source- and finished-water samples represents an initial assessment of whether compounds present in source water also are present in finished water and is not intended as an evaluation of water-treatment efficacy. The treatment used at the majority of the community water systems sampled is disinfection, which, in general, is not designed to remove the compounds monitored in this study. Concentrations of all compounds detected in finished water were less than their human-health benchmarks. Two detections of perchloroethene and one detection of trichloroethene in finished water had concentrations within an order of magnitude of the MCL. Concentrations of disinfection by-products were

Water quality impacts from an ORV trail stream crossing in the Talladega National Forest, Alabama, USA

Treesearch

Renee D. Ayala; Puneet Srivastava; Christian J. Brodbeck; Emily a. Carter; Timothy P. McDonald

2005-01-01

Off-Road Vehicles (ORVs) are one of the most damaging forms of recreation utilized in our National Forests. Erosion from ORV trails can be a major source of water quality impact. In 2003, a study was initiated in the Talladega National Forest to quantifjl water quality impacts of an ORV trail crossing a local stream. Automated samplers were installed upstream and...

Using a hybrid model to predict solute transfer from initially saturated soil into surface runoff with controlled drainage water.

PubMed

Tong, Juxiu; Hu, Bill X; Yang, Jinzhong; Zhu, Yan

2016-06-01

The mixing layer theory is not suitable for predicting solute transfer from initially saturated soil to surface runoff water under controlled drainage conditions. By coupling the mixing layer theory model with the numerical model Hydrus-1D, a hybrid solute transfer model has been proposed to predict soil solute transfer from an initially saturated soil into surface water, under controlled drainage water conditions. The model can also consider the increasing ponding water conditions on soil surface before surface runoff. The data of solute concentration in surface runoff and drainage water from a sand experiment is used as the reference experiment. The parameters for the water flow and solute transfer model and mixing layer depth under controlled drainage water condition are identified. Based on these identified parameters, the model is applied to another initially saturated sand experiment with constant and time-increasing mixing layer depth after surface runoff, under the controlled drainage water condition with lower drainage height at the bottom. The simulation results agree well with the observed data. Study results suggest that the hybrid model can accurately simulate the solute transfer from initially saturated soil into surface runoff under controlled drainage water condition. And it has been found that the prediction with increasing mixing layer depth is better than that with the constant one in the experiment with lower drainage condition. Since lower drainage condition and deeper ponded water depth result in later runoff start time, more solute sources in the mixing layer are needed for the surface water, and larger change rate results in the increasing mixing layer depth.

Sources Contributing Inorganic Species to Drinking Water Intakes During Low Flow Conditions on the Allegheny River in Western Pennsylvania

EPA Science Inventory

The U.S. Environmental Protection Agency (EPA) is conducting a study of the potential impacts of hydraulic fracturing for oil and gas on drinking water resources. This study was initiated in Fiscal Year 2010 when Congress urged the EPA to examine the relationship between hydraul...

Spatial scale of land-use impacts on riverine drinking source water quality

NASA Astrophysics Data System (ADS)

Hurley, Tim; Mazumder, Asit

2013-03-01

Drinking water purveyors are increasingly relying on land conservation and management to ensure the safety of the water that they provide to consumers. To cost-effectively implement any such landscape initiatives, resources must be targeted to the appropriate spatial scale to address quality impairments of concern in a cost-effective manner. Using data gathered from 40 Canadian rivers across four ecozones, we examined the spatial scales at which land use was most closely associated with drinking source water quality metrics. Exploratory linear mixed-effects models accounting for climatic, hydrological, and physiographic variation among sites suggested that different spatial areas of land-use influence drinking source water quality depending on the parameter and season investigated. Escherichia coli spatial variability was only associated with land use at a local (5-10 km) spatial scale. Turbidity measures exhibited a complex association with land use, suggesting that the land-use areas of greatest influence can range from a 1 km subcatchment to the entire watershed depending on the season. Total organic carbon concentrations were only associated with land use characterized at the entire watershed scale. The Canadian Council of Ministers of the Environment Water Quality Index was used to calculate a composite measure of seasonal drinking source water quality but did not provide additional information beyond the analyses of individual parameters. These results suggest that entire watershed management is required to safeguard drinking water sources with more focused efforts at targeted spatial scales to reduce specific risk parameters.

INEEL Source Water Assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sehlke, Gerald

2003-03-01

The Idaho National Engineering and Environmental Laboratory (INEEL) covers approximately 890 mi2 and includes 12 public water systems that must be evaluated for Source water protection purposes under the Safe Drinking Water Act. Because of its size and location, six watersheds and five aquifers could potentially affect the INEEL’s drinking water sources. Based on a preliminary evaluation of the available information, it was determined that the Big Lost River, Birch Creek, and Little Lost River Watersheds and the eastern Snake River Plain Aquifer needed to be assessed. These watersheds were delineated using the United States Geologic Survey’s Hydrological Unit scheme.more » Well capture zones were originally estimated using the RESSQC module of the Environmental Protection Agency’s Well Head Protection Area model, and the initial modeling assumptions and results were checked by running several scenarios using Modflow modeling. After a technical review, the resulting capture zones were expanded to account for the uncertainties associated with changing groundwater flow directions, a thick vadose zone, and other data uncertainties. Finally, all well capture zones at a given facility were merged to a single wellhead protection area at each facility. A contaminant source inventory was conducted, and the results were integrated with the well capture zones, watershed and aquifer information, and facility information using geographic information system technology to complete the INEEL’s Source Water Assessment. Of the INEEL’s 12 public water systems, three systems rated as low susceptibility (EBR-I, Main Gate, and Gun Range), and the remainder rated as moderate susceptibility. No INEEL public water system rated as high susceptibility. We are using this information to develop a source water management plan from which we will subsequently implement an INEEL-wide source water management program. The results are a very robust set of wellhead protection areas that will protect the INEEL’s public water systems yet not too conservative to inhibit the INEEL from carrying out its missions.« less

The Idaho National Engineering and Environmental Laboratory Source Water Assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sehlke, G.

2003-03-17

The Idaho National Engineering and Environmental Laboratory (INEEL) covers approximately 890 square miles and includes 12 public water systems that must be evaluated for Source water protection purposes under the Safe Drinking Water Act. Because of its size and location, six watersheds and five aquifers could potentially affect the INEEL's drinking water sources. Based on a preliminary evaluation of the available information, it was determined that the Big Lost River, Birch Creek, and Little Lost River Watersheds and the eastern Snake River Plain Aquifer needed to be assessed. These watersheds were delineated using the United States Geologic Survey's Hydrological Unitmore » scheme. Well capture zones were originally estimated using the RESSQC module of the Environmental Protection Agency's Well Head Protection Area model, and the initial modeling assumptions and results were checked by running several scenarios using Modflow modeling. After a technical review, the resulting capture zones were expanded to account for the uncertainties associated with changing groundwater flow directions, a this vadose zone, and other data uncertainties. Finally, all well capture zones at a given facility were merged to a single wellhead protection area at each facility. A contaminant source inventory was conducted, and the results were integrated with the well capture zones, watershed and aquifer information, and facility information using geographic information system technology to complete the INEEL's Source Water Assessment. Of the INEEL's 12 public water systems, three systems rated as low susceptibility (EBR-1, Main Gate, and Gun Range), and the remainder rated as moderate susceptibility. No INEEL public water system rated as high susceptibility. We are using this information to develop a source water management plan from which we will subsequently implement an INEEL-wide source water management program. The results are a very robust set of wellhead protection areas that will protect the INEEL's public water systems yet not too conservative to inhibit the INEEL from carrying out its missions.« less

Source to point of use drinking water changes and knowledge, attitude and practices in Katsina State, Northern Nigeria

NASA Astrophysics Data System (ADS)

Onabolu, B.; Jimoh, O. D.; Igboro, S. B.; Sridhar, M. K. C.; Onyilo, G.; Gege, A.; Ilya, R.

In many Sub-Saharan countries such as Nigeria, inadequate access to safe drinking water is a serious problem with 37% in the region and 58% of rural Nigeria using unimproved sources. The global challenge to measuring household water quality as a determinant of safety is further compounded in Nigeria by the possibility of deterioration from source to point of use. This is associated with the use of decentralised water supply systems in rural areas which are not fully reticulated to the household taps, creating a need for an integrated water quality monitoring system. As an initial step towards establishing the system in the north west and north central zones of Nigeria, The Katsina State Rural Water and Sanitation Agency, responsible for ensuring access to safe water and adequate sanitation to about 6 million people carried out a three pronged study with the support of UNICEF Nigeria. Part 1 was an assessment of the legislative and policy framework, institutional arrangements and capacity for drinking water quality monitoring through desk top reviews and Key Informant Interviews (KII) to ascertain the institutional capacity requirements for developing the water quality monitoring system. Part II was a water quality study in 700 households of 23 communities in four local government areas. The objectives were to assess the safety of drinking water, compare the safety at source and household level and assess the possible contributory role of end users’ Knowledge Attitudes and Practices. These were achieved through water analysis, household water quality tracking, KII and questionnaires. Part III was the production of a visual documentary as an advocacy tool to increase awareness of the policy makers of the linkages between source management, treatment and end user water quality. The results indicate that except for pH, conductivity and manganese, the improved water sources were safe at source. However there was a deterioration in water quality between source and point of use in 18%, 12.5%, 27% and 50% of hand pump fitted boreholes, motorised boreholes, hand dug wells and streams respectively. Although no statistical correlation could be drawn between water management practices and water quality deterioration, the survey of the study households gave an indication of the possible contributory role of their knowledge, attitudes and practices to water contamination after provision. Some of the potential water related sources of contamination were poor source protection and location, use of unimproved water source and poor knowledge and practice of household water treatment methods, poor hand washing practices in terms of percentage that wash hands and use soap. Consequently 34 WASH departments have been created at the local government level towards establishment of a community based monitoring system and piloting has begun in Kaita local government area.

Dissolved Organic Matter Compositional Change and Biolability During Two Storm Runoff Events in a Small Agricultural Watershed

NASA Astrophysics Data System (ADS)

Eckard, Robert S.; Pellerin, Brian A.; Bergamaschi, Brian A.; Bachand, Philip A. M.; Bachand, Sandra M.; Spencer, Robert G. M.; Hernes, Peter J.

2017-10-01

Agricultural watersheds are globally pervasive, supporting fundamentally different organic matter source, composition, and concentration profiles in comparison to natural systems. Similar to natural systems, agricultural storm runoff exports large amounts of organic carbon from agricultural land into waterways. But intense management of upper soil layers, waterway channelization, wetland and riparian habitat removal, and postharvest vegetation removal promise to uniquely drive organic matter release to waterways. During a winter first flush and a subsequent storm event, this study investigated the influence of a small agricultural watershed on dissolved organic matter (DOM) source, composition, and biolability. Storm water discharge released strongly terrestrial yet biolabile (23 to 32%) dissolved organic carbon (DOC). Following a 21 day bioassay, a parallel factor analysis identified an 80% reduction in a protein-like (phenylpropyl) component (C2) that was previously correlated to lignin phenol concentration, and a 10% reduction in a humic-like, terrestrially sourced component (C4). Storm-driven releases tripled DOC concentration (from 2.8 to 8.7 mg L-1) during the first flush event in comparison to base flow and were terrestrially sourced, with an eightfold increase in vascular plant derived lignin phenols (23.0 to 185 μg L-1). As inferred from system hydrology, lignin composition, and nitrate as a groundwater tracer, an initial pulse of dilute water from the upstream watershed caused a counterclockwise DOC hysteresis loop. DOC concentrations peaked after 3.5 days, with the delay between peak discharge and peak DOC attributed to storm water hydrology and a period of initial water repellency of agricultural soils, which delayed DOM leaching.

Denatured ethanol release into gasoline residuals, Part 1: source behaviour.

PubMed

Freitas, Juliana G; Barker, James F

2013-05-01

With the increasing use of ethanol in fuels, it is important to evaluate its fate when released into the environment. While ethanol is less toxic than other organic compounds present in fuels, one of the concerns is the impact ethanol might have on the fate of gasoline hydrocarbons in groundwater. One possible concern is the spill of denatured ethanol (E95: ethanol containing 5% denaturants, usually hydrocarbons) in sites with pre-existing gasoline contamination. In that scenario, ethanol is expected to increase the mobility of the NAPL phase by acting as a cosolvent and decreasing interfacial tension. To evaluate the E95 behaviour and its impacts on pre-existing gasoline, a field test was performed at the CFB-Borden aquifer. Initially gasoline contamination was created releasing 200 L of E10 (gasoline with 10% ethanol) into the unsaturated zone. One year later, 184 L of E95 was released on top of the gasoline contamination. The site was monitored using soil cores, multilevel wells and one glass access tube. At the end of the test, the source zone was excavated and the compounds remaining were quantified. E95 ethanol accumulated and remained within the capillary fringe and unsaturated zone for more than 200 days, despite ~1m oscillations in the water table. The gasoline mobility increased and it was redistributed in the source zone. Gasoline NAPL saturations in the soil increased two fold in the source zone. However, water table oscillations caused a separation between the NAPL and ethanol: NAPL was smeared and remained in deeper positions while ethanol moved upwards following the water table rise. Similarly, the E95 denaturants that initially were within the ethanol-rich phase became separated from ethanol after the water table oscillation, remaining below the ethanol rich zone. The separation between ethanol and hydrocarbons in the source after water table oscillation indicates that ethanol's impact on hydrocarbon residuals is likely limited to early times. Copyright © 2013 Elsevier B.V. All rights reserved.

Water Pollution Prediction in the Three Gorges Reservoir Area and Countermeasures for Sustainable Development of the Water Environment

PubMed Central

Huang, Shuaijin; Qu, Xuexin

2017-01-01

The Three Gorges Project was implemented in 1994 to promote sustainable water resource use and development of the water environment in the Three Gorges Reservoir Area (hereafter “Reservoir Area”). However, massive discharge of wastewater along the river threatens these goals; therefore, this study employs a grey prediction model (GM) to predict the annual emissions of primary pollution sources, including industrial wastewater, domestic wastewater, and oily and domestic wastewater from ships, that influence the Three Gorges Reservoir Area water environment. First, we optimize the initial values of a traditional GM (1,1) model, and build a new GM (1,1) model that minimizes the sum of squares of the relative simulation errors. Second, we use the new GM (1,1) model to simulate historical annual emissions data for the four pollution sources and thereby test the effectiveness of the model. Third, we predict the annual emissions of the four pollution sources in the Three Gorges Reservoir Area for a future period. The prediction results reveal the annual emission trends for the major wastewater types, and indicate the primary sources of water pollution in the Three Gorges Reservoir Area. Based on our predictions, we suggest several countermeasures against water pollution and towards the sustainable development of the water environment in the Three Gorges Reservoir Area. PMID:29077006

Overview of the Texas Source Water Assessment Project

USGS Publications Warehouse

Ulery, Randy L.

2000-01-01

The 1996 Amendments to the Safe Drinking Water Act require, for the first time, that each state prepare a source water assessment for all PWS. Previously, Federal regulations focused on sampling and enforcement with emphasis on the quality of delivered water. These Amendments emphasize the importance of protecting the source water. States are required to determine the drinking-water source, the origin of contaminants monitored or the potential contaminants to be monitored, and the intrinsic susceptibility of the source water. Under the amendments to the Act, States must create SWAP Programs. The programs must include an individual source water assessment for each public water system regulated by the State. These assessments will determine whether an individual drinking water source is susceptible to contamination. During 1997?99, TNRCC and USGS staff met as subject-matter working groups to develop an approach to conducting Source Water Susceptibility Assessments (SWSA) and a draft workplan. The draft workplan was then presented to and reviewed by various stakeholder and technical advisory groups. Comments and suggestions from these groups were considered, and a final workplan was produced and presented to the EPA. After EPA approval, work formally began on the Texas SWAP Project. The project has an expected completion date of September 2002. At that time, initial SWSA of all Texas public water supplies should be complete. Ground-water supplies can be considered susceptible if a possible source of contamination (PSOC) exists in the contributing area for the public-supply well field or spring, the contaminant travel time to the well field or spring is short, and the soil zone, vadose zone, and aquifer-matrix materials are unlikely to adequately attenuate the contaminants associated with the PSOC. In addition, particular types of land use/cover within the contributing area may cause the supply to be deemed more susceptible to contamination. Finally, detection of various classes of constituents in water from wells in the vicinity of a public supply well may indicate susceptibility of the public-supply well even though there may be no identifiable PSOC or land use activity. Surface-water supplies are by nature susceptible to contamination from both point and non-point sources. The degree of susceptibility of a PWS to contamination can vary and is a function of the environmental setting, water and wastewater management practices, and land use/cover within a water supply's contributing watershed area. For example, a PWS intake downstream from extensive urban development may be more susceptible to non-point source contamination than a PWS intake downstream from a forested, relatively undeveloped watershed. Surface-water supplies are also susceptible to contamination from point sources, which may include permitted discharges, as well as accidental spills or other introduction of contaminants.

Inferring the source of evaporated waters using stable H and O isotopes

NASA Astrophysics Data System (ADS)

Bowen, G. J.; Putman, A.; Brooks, J. R.; Bowling, D. R.; Oerter, E.; Good, S. P.

2017-12-01

Stable isotope ratios of H and O are widely used identify the source of water, e.g., in aquifers, river runoff, soils, plant xylem, and plant-based beverages. In situations where the sampled water is partially evaporated, its isotope values will have evolved along an evaporation line (EL) in δ2H/δ18O space, and back-correction along the EL to its intersection with a meteoric water line (MWL) has been used to estimate the source water's isotope ratios. Several challenges and potential pitfalls exist with traditional approaches to this problem, including potential for bias from a commonly used regression-based approach for EL slope estimation and incomplete estimation of uncertainty in most studies. We suggest the value of a model-based approach to EL estimation, and introduce a mathematical framework that eliminates the need to explicitly estimate the EL-MWL intersection, simplifying analysis and facilitating more rigorous uncertainty estimation. We apply this analysis framework to data from 1,000 lakes sampled in EPA's 2007 National Lakes Assessment. We find that data for most lakes is consistent with a water source similar to annual runoff, estimated from monthly precipitation and evaporation within the lake basin. Strong evidence for both summer- and winter-biased sources exists, however, with winter bias pervasive in most snow-prone regions. The new analytical framework should improve the rigor of source-water inference from evaporated samples in ecohydrology and related sciences, and our initial results from U.S. lakes suggest that previous interpretations of lakes as unbiased isotope integrators may only be valid in certain climate regimes.

Aquatic exposures of chemical mixtures in urban environments: Approaches to impact assessment.

PubMed

de Zwart, Dick; Adams, William; Galay Burgos, Malyka; Hollender, Juliane; Junghans, Marion; Merrington, Graham; Muir, Derek; Parkerton, Thomas; De Schamphelaere, Karel A C; Whale, Graham; Williams, Richard

2018-03-01

Urban regions of the world are expanding rapidly, placing additional stress on water resources. Urban water bodies serve many purposes, from washing and sources of drinking water to transport and conduits for storm drainage and effluent discharge. These water bodies receive chemical emissions arising from either single or multiple point sources, diffuse sources which can be continuous, intermittent, or seasonal. Thus, aquatic organisms in these water bodies are exposed to temporally and compositionally variable mixtures. We have delineated source-specific signatures of these mixtures for diffuse urban runoff and urban point source exposure scenarios to support risk assessment and management of these mixtures. The first step in a tiered approach to assessing chemical exposure has been developed based on the event mean concentration concept, with chemical concentrations in runoff defined by volumes of water leaving each surface and the chemical exposure mixture profiles for different urban scenarios. Although generalizations can be made about the chemical composition of urban sources and event mean exposure predictions for initial prioritization, such modeling needs to be complemented with biological monitoring data. It is highly unlikely that the current paradigm of routine regulatory chemical monitoring alone will provide a realistic appraisal of urban aquatic chemical mixture exposures. Future consideration is also needed of the role of nonchemical stressors in such highly modified urban water bodies. Environ Toxicol Chem 2018;37:703-714. © 2017 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC. © 2017 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.

Characterization of novel Bacillus strain N31 from mariculture water capable of halophilic heterotrophic nitrification-aerobic denitrification.

PubMed

Huang, Fei; Pan, Luqing; Lv, Na; Tang, Xianming

2017-11-01

The development of an intensive aquaculture industry has been accompanied by increasing environmental impacts, especially nitrogen pollution. In this study, a novel halophilic bacterium capable of heterotrophic nitrification and aerobic denitrification was isolated from mariculture water and identified as Bacillus litoralis N31. The efficiency of ammonium, nitrite and nitrate removal by N31 were 86.3%, 89.3% and 89.4%, respectively, after a 48-h cultivation in sole N-source medium with initial nitrogen approximately 20 mg/L. However, ammonium was removed preferentially, and no obvious nitrite accumulated during the simultaneous nitrification and denitrification process in mixed N-source media. The existence of hao, napA and nirS genes further proved the heterotrophic nitrification-aerobic denitrification capability of N31. The optimal conditions for ammonium removal were 30°C, initial pH 7.5-8.5, C/N ratio 5-20 and salinity 30-40‰, and the nitrification rate of N31 increased with increasing initial [Formula: see text] from 10 to 250 mg/L. Biosecurity assessment with shrimp indicated that strain N31 could be applied in the marine aquaculture industry safely for culture water remediation and effluent treatment. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Source investigation of two outbreaks of skin and soft tissue infection by Mycobacterium abscessus subsp. abscessus in Venezuela.

PubMed

Torres-Coy, J A; Rodríguez-Castillo, B A; Pérez-Alfonzo, R; DE Waard, J H

2016-04-01

Outbreaks of soft tissue or skin infection due to non-tuberculous mycobacteria are reported frequently in scientific journals but in general the infection source in these outbreaks remains unknown. In Venezuela, in two distinct outbreaks, one after breast augmentation surgery and another after hydrolipoclasy therapy, 16 patients contracted a soft tissue infection due to Mycobacterium abscessus subsp. abscessus. Searching for the possible environmental infection sources in these outbreaks, initially the tap water (in the hydrolipoclasy therapy outbreak) and a surgical skin marker (in the breast implant surgery outbreak), were identified as the infection sources. Molecular typing of the strains with a variable number tandem repeat typing assay confirmed the tap water as the infection source but the molecular typing technique excluded the skin marker. We discuss the results and make a call for the implementation of stringent hygiene and disinfection guidelines for cosmetic procedures in Venezuela.

'On-line' analyses of simulated solar wind implantations of terrestrial analogs of lunar materials

NASA Technical Reports Server (NTRS)

Blanford, G. E.; Bergesen, P.; Moeller, W.; Maurette, M.; Monart, B.

1986-01-01

In connection with the establishment of a lunar base, it would be necessary to provide water, and the feasibility to obtain water from solar wind (SW) implanted lunar soils has been considered. In this context, a project involving the examination of materials under conditions of simulated SW irradiation has been initiated. A description is presented of initial results on oligoclase, ilmenite, and simulated lunar glass (SLG). Attention is given to the reaction chamber, the target materials, the saturation concentrations, aspects of water release, depth profiles, thermal release, effects from helium-3 preimplants, mechanisms of possible water release related to direct emission and thermal release, and lunar soil components enriched in trapped SW hydrogen. It is found that ilmenite stores about twice as much deuterium as the other target materials. However, it is unknown whether the small enrichment factor will be sufficient to make the material a potential source of lunar water.

Quantifying Apparent Groundwater Ages near Managed Aquifer Recharge Operations Using Radio-Sulfur ( 35S) as an Intrinsic Tracer

DOE PAGES

Clark, Jordan; Urióstegui, Stephanie; Bibby, Richard; ...

2016-10-25

The application of the cosmogenic radioisotope sulfur-35 ( 35S) as a chronometer near spreading basins is evaluated at two well-established Managed Aquifer Recharge (MAR) sites: the Atlantis facility (South Africa) and Orange County Water District’s (OCWD’s) Kraemer Basin (Northern Orange County, CA, USA). Source water for both of these sites includes recycled wastewater. Despite lying nearer to the outlet end of their respective watersheds than to the headwaters, 35S was detected in most of the water sampled, including from wells found close to the spreading ponds and in the source water. Dilution with 35S-dead continental SO 4 was minimal, amore » surprising finding given its short ~3 month half-life. The initial work at the Atlantis MAR site demonstrated that remote laboratories could be set up and that small volume samples—saline solutions collected after the resin elution step from the recently developed batch method described below—can be stored and transported to the counting laboratory. This study also showed that the batch method needed to be altered to remove unknown compounds eluted from the resin along with SO 4. Using the improved batch method, times series measurements of both source and well water from OCWD’s MAR site showed significant temporal variations. Finally, this result indicates that during future studies, monthly to semi-monthly sampling should be conducted. Nevertheless, both of these initial studies suggest the 35S chronometer may become a valuable tool for managing MAR sites where regulations require minimum retention times.« less

Quantifying Apparent Groundwater Ages near Managed Aquifer Recharge Operations Using Radio-Sulfur ( 35S) as an Intrinsic Tracer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clark, Jordan; Urióstegui, Stephanie; Bibby, Richard

The application of the cosmogenic radioisotope sulfur-35 ( 35S) as a chronometer near spreading basins is evaluated at two well-established Managed Aquifer Recharge (MAR) sites: the Atlantis facility (South Africa) and Orange County Water District’s (OCWD’s) Kraemer Basin (Northern Orange County, CA, USA). Source water for both of these sites includes recycled wastewater. Despite lying nearer to the outlet end of their respective watersheds than to the headwaters, 35S was detected in most of the water sampled, including from wells found close to the spreading ponds and in the source water. Dilution with 35S-dead continental SO 4 was minimal, amore » surprising finding given its short ~3 month half-life. The initial work at the Atlantis MAR site demonstrated that remote laboratories could be set up and that small volume samples—saline solutions collected after the resin elution step from the recently developed batch method described below—can be stored and transported to the counting laboratory. This study also showed that the batch method needed to be altered to remove unknown compounds eluted from the resin along with SO 4. Using the improved batch method, times series measurements of both source and well water from OCWD’s MAR site showed significant temporal variations. Finally, this result indicates that during future studies, monthly to semi-monthly sampling should be conducted. Nevertheless, both of these initial studies suggest the 35S chronometer may become a valuable tool for managing MAR sites where regulations require minimum retention times.« less

Chromophoric dissolved organic matter of black waters in a highly eutrophic Chinese lake: Freshly produced from algal scums?

PubMed

Zhou, Yongqiang; Jeppesen, Erik; Zhang, Yunlin; Niu, Cheng; Shi, Kun; Liu, Xiaohan; Zhu, Guangwei; Qin, Boqiang

2015-12-15

Field campaigns and an incubation experiment were conducted to evaluate the sources of chromophoric dissolved organic matter (CDOM) in black water spots in highly polluted regions of the Chinese Lake Taihu. A significant positive correlation (p<0.0001) was found between chlorophyll a (Chl-a) and the CDOM absorption coefficient a(350), indicating that algae degradation was likely the primary source of CDOM in black waters. This is supported by our field results that Chl-a, a(350) and the spectral slope ratio (SR) were significantly higher in the black water samples than in the regular samples (p<0.001). Our incubation experiment further substantiated the primary significance of biological CDOM source where a(350) increased with decreasing Chl-a concentrations. After seven days' incubation, a 72.2% decrease and a 74.9% increase were recorded for Chl-a and a(350), respectively, relative to the initial values. Parallel factor analysis identified five fluorescent components. The maximal fluorescence intensity (Fmax) of tryptophan-like C1 and microbial humic-like C3 of black water samples was significantly higher than in the regular water samples (p<0.0005). This is consistent with incubation experiment results showing a rapid increase in Fmax of the two components, emphasizing the priority of the in situ biological CDOM source in black water spots. Copyright © 2015 Elsevier B.V. All rights reserved.

The New Method of Tsunami Source Reconstruction With r-Solution Inversion Method

NASA Astrophysics Data System (ADS)

Voronina, T. A.; Romanenko, A. A.

2016-12-01

Application of the r-solution method to reconstructing the initial tsunami waveform is discussed. This methodology is based on the inversion of remote measurements of water-level data. The wave propagation is considered within the scope of a linear shallow-water theory. The ill-posed inverse problem in question is regularized by means of a least square inversion using the truncated Singular Value Decomposition method. As a result of the numerical process, an r-solution is obtained. The method proposed allows one to control the instability of a numerical solution and to obtain an acceptable result in spite of ill posedness of the problem. Implementation of this methodology to reconstructing of the initial waveform to 2013 Solomon Islands tsunami validates the theoretical conclusion for synthetic data and a model tsunami source: the inversion result strongly depends on data noisiness, the azimuthal and temporal coverage of recording stations with respect to the source area. Furthermore, it is possible to make a preliminary selection of the most informative set of the available recording stations used in the inversion process.

Possible Sources for Methane and C2-C5 Organics in the Plume of Enceladus

NASA Technical Reports Server (NTRS)

McKay, Chris; Khare, Bishun N.; Amin, Ranjamin; Klasson, Martin; Kral, Timothy A.

2012-01-01

In this paper we consider six possible sources of CH4 and other low-mass (C2 - C5) organics in the plume of Enceladus: initial endowments of cometary organics or Titan- like tholin, in situ production by Fisher-Tropsch type reactions, water-rock reactions, or microbiology, and thermogenesis from heavier organics already present. We report on new laboratory results C2 hydrocarbons released on thermogenesis of laboratory tholin and Fisher-Tropsch type synthesis. Tholin heating produced ratios of CH4/C2H4 and CH4/C2H6 of about 2 for temperatures up to 450 C and about 6 for a temperature of 650 C. Low pressure Fisher-Tropsch type experiments produced CH4/C2H4 of approx 1.5, similar to previous results. No C2H2 was produced by either process. Tests of gas production by four strains of methanogens confirmed the absence of any detectable production of non-methane hydrocarbons. Cometary endowment, Fisher-Tropsch type synthesis, and Titan-like tholin incorporation could be primary inputs of organics and subsequent thermal processing of any of these all are possible sources of low mass organics in the plume. Biological production and water-rock reactions are an alternative source of CH4. Neither water-- ]rock reactions or thermal processing of biomass could be a source C2 . C5 organics due to the low interior pressures. The confirmed detection of CO and C2H2 in the plume of Enceladus would provide an important constraint on sources as we have identified no process . other than the initial volatile component of cometary organics which can supply these gases. Precise determination of the relative concentrations of C1 - C5 hydrocarbons may provide additional constraints on sources but a detailed isotopic analysis of C and H in these organics and a search for amino acids constitute the next important steps in resolving the sources of the organics in Enceladus' plume.

Presence of Pathogens and Indicator Microbes at a Non-Point Source Subtropical Recreational Marine Beach ▿ †

PubMed Central

Abdelzaher, Amir M.; Wright, Mary E.; Ortega, Cristina; Solo-Gabriele, Helena M.; Miller, Gary; Elmir, Samir; Newman, Xihui; Shih, Peter; Bonilla, J. Alfredo; Bonilla, Tonya D.; Palmer, Carol J.; Scott, Troy; Lukasik, Jerzy; Harwood, Valerie J.; McQuaig, Shannon; Sinigalliano, Chris; Gidley, Maribeth; Plano, Lisa R. W.; Zhu, Xiaofang; Wang, John D.; Fleming, Lora E.

2010-01-01

Swimming in ocean water, including ocean water at beaches not impacted by known point sources of pollution, is an increasing health concern. This study was an initial evaluation of the presence of indicator microbes and pathogens and the association among the indicator microbes, pathogens, and environmental conditions at a subtropical, recreational marine beach in south Florida impacted by non-point sources of pollution. Twelve water and eight sand samples were collected during four sampling events at high or low tide under elevated or reduced solar insolation conditions. The analyses performed included analyses of fecal indicator bacteria (FIB) (fecal coliforms, Escherichia coli, enterococci, and Clostridium perfringens), human-associated microbial source tracking (MST) markers (human polyomaviruses [HPyVs] and Enterococcus faecium esp gene), and pathogens (Vibrio vulnificus, Staphylococcus aureus, enterovirus, norovirus, hepatitis A virus, Cryptosporidium spp., and Giardia spp.). The enterococcus concentrations in water and sand determined by quantitative PCR were greater than the concentrations determined by membrane filtration measurement. The FIB concentrations in water were below the recreational water quality standards for three of the four sampling events, when pathogens and MST markers were also generally undetectable. The FIB levels exceeded regulatory guidelines during one event, and this was accompanied by detection of HPyVs and pathogens, including detection of the autochthonous bacterium V. vulnificus in sand and water, detection of the allochthonous protozoans Giardia spp. in water, and detection of Cryptosporidium spp. in sand samples. The elevated microbial levels were detected at high tide and under low-solar-insolation conditions. Additional sampling should be conducted to further explore the relationships between tidal and solar insolation conditions and between indicator microbes and pathogens in subtropical recreational marine waters impacted by non-point source pollution. PMID:19966020

Rural drinking water at supply and household levels: quality and management.

PubMed

Hoque, Bilqis A; Hallman, Kelly; Levy, Jason; Bouis, Howarth; Ali, Nahid; Khan, Feroze; Khanam, Sufia; Kabir, Mamun; Hossain, Sanower; Shah Alam, Mohammad

2006-09-01

Access to safe drinking water has been an important national goal in Bangladesh and other developing countries. While Bangladesh has almost achieved accepted bacteriological drinking water standards for water supply, high rates of diarrheal disease morbidity indicate that pathogen transmission continues through water supply chain (and other modes). This paper investigates the association between water quality and selected management practices by users at both the supply and household levels in rural Bangladesh. Two hundred and seventy tube-well water samples and 300 water samples from household storage containers were tested for fecal coliform (FC) concentrations over three surveys (during different seasons). The tube-well water samples were tested for arsenic concentration during the first survey. Overall, the FC was low (the median value ranged from 0 to 4 cfu/100ml) in water at the supply point (tube-well water samples) but significantly higher in water samples stored in households. At the supply point, 61% of tube-well water samples met the Bangladesh and WHO standards of FC; however, only 37% of stored water samples met the standards during the first survey. When arsenic contamination was also taken into account, only 52% of the samples met both the minimum microbiological and arsenic content standards of safety. The contamination rate for water samples from covered household storage containers was significantly lower than that of uncovered containers. The rate of water contamination in storage containers was highest during the February-May period. It is shown that safe drinking water was achieved by a combination of a protected and high quality source at the initial point and maintaining quality from the initial supply (source) point through to final consumption. It is recommended that the government and other relevant actors in Bangladesh establish a comprehensive drinking water system that integrates water supply, quality, handling and related educational programs in order to ensure the safety of drinking water supplies.

Who messed up my lake?

EPA Science Inventory

Initial results from a lake-wide agent based simulation releasing virtual drifters from multiple tributaries over time. We examine the use of agent based modeling to break down the sources contributing to the composition of nearshore waters. Knowing that flow is highly biased in ...

New Theory for Tsunami Propagation and Estimation of Tsunami Source Parameters

NASA Astrophysics Data System (ADS)

Mindlin, I. M.

2007-12-01

In numerical studies based on the shallow water equations for tsunami propagation, vertical accelerations and velocities within the sea water are neglected, so a tsunami is usually supposed to be produced by an initial free surface displacement in the initially still sea. In the present work, new theory for tsunami propagation across the deep sea is discussed, that accounts for the vertical accelerations and velocities. The theory is based on the solutions for the water surface displacement obtained in [Mindlin I.M. Integrodifferential equations in dynamics of a heavy layered liquid. Moscow: Nauka*Fizmatlit, 1996 (Russian)]. The solutions are valid when horizontal dimensions of the initially disturbed area in the sea surface are much larger than the vertical displacement of the surface, which applies to the earthquake tsunamis. It is shown that any tsunami is a combination of specific basic waves found analytically (not superposition: the waves are nonlinear), and consequently, the tsunami source (i.e., the initially disturbed body of water) can be described by the numerable set of the parameters involved in the combination. Thus the problem of theoretical reconstruction of a tsunami source is reduced to the problem of estimation of the parameters. The tsunami source can be modelled approximately with the use of a finite number of the parameters. Two-parametric model is discussed thoroughly. A method is developed for estimation of the model's parameters using the arrival times of the tsunami at certain locations, the maximum wave-heights obtained from tide gauge records at the locations, and the distances between the earthquake's epicentre and each of the locations. In order to evaluate the practical use of the theory, four tsunamis of different magnitude occurred in Japan are considered. For each of the tsunamis, the tsunami energy (E below), the duration of the tsunami source formation T, the maximum water elevation in the wave originating area H, mean radius of the area R, and the average magnitude of the sea surface displacement at the margin of the wave originating area h are estimated using tide gauges records. The results are compared (and, in the author's opinion, are in line) with the estimates known in the literature. Compared to the methods employed in the literature, there is no need to use bathymetry (and, consequently, refraction diagrams) for the estimations. The present paper follows closely earlier works [Mindlin I.M., 1996; Mindlin I.M. J. Appl. Math. Phys. (ZAMP), 2004, vol.55, pp. 781-799] and adds to their theoretical results. Example. The Hiuganada earthquake of 1968, April, 1, 9h 42m JST. A tsunami of moderate size arrived at the coast of the south-western part of Shikoku and the eastern part of Kyushu, Japan. Tsunami parameters listed above are estimated with the theory being discussed for two models of tsunami generation: (a) by initial free surface displacement (the case for numerical studies): E=1.91· 1012J, R=22km, h=17.2cm; and (b) by a sudden change in the velocity field of initially still water: E=8.78· 1012J, R=20.4km, h=9.2cm. These values are in line with known estimates [Soloviev S.L., Go Ch.N. Catalogue of tsunami in the West of Pacific Ocean. Moscow, 1974]: E=1.3· 1013J (attributed to Hatori), E=(1.4 - 2.2)· 1012J (attributed to Aida), R=21.2km, h=20cm [Hatory T., Bull. Earthq. Res. Inst., Tokyo Univ., 1969, vol. 47, pp. 55-63]. Also, estimates are obtained for the values that could not be found based on shallow water wave theory: (a) H=3.43m and (b) H=1.38m, T=16.4sec.

Microbial and geochemical quality of shallow well water in high-density areas in Mzuzu City in Malawi

NASA Astrophysics Data System (ADS)

Msilimba, Golden; Wanda, Elijah M. M.

In Malawi, shallow wells constitute the most important water sources for domestic purposes. However, increasing human population coupled with poor sanitation and infrastructure is undermining the quality of shallow well water. An assessment of microbial and geochemical quality of shallow well water in high-density areas of Zolozolo, Ching’ambo and Chiputula in Mzuzu City, Northern Malawi, has been carried out. The study aimed at characterising domestic water sources, identifying possible sources of water contamination and determining levels of microbial and chemical contamination. Arc-view GIS was used to map the water sources. A questionnaire survey was carried out to elicit information on characteristics of drinking water sources. Water samples were collected from quasi-randomly selected shallow wells and analysed for microbial and chemical parameters using standard methods. HCA, performed using R-programme, was used to group sampled sites according to their bio-physicochemical characteristics. Compliance of the water with MBS/WHO water quality guidelines was determined. The WQI was computed to turn multifaceted data obtained from laboratory analyses into simple information that is comprehensible and useable by the public to assess overall quality of water at a specific water points. The GW-chart was used to show hydrogeochemical water types from each sampled site. Microbial analysis revealed that water from 96.3% of shallow wells recorded faecal coliforms ranging from 129 to 920 cfu per 100 ml which were significantly higher than the Malawi Standards and WHO thresholds. In general, shallow well water is of low mineralisation (EC range 80-500 μS cm-1), with hydrogeochemical facies dominated by Ca-HCO3, which evolves to Ca-Cl water type. The shallow well water registered a WQI range of 50.16-66.04%, with a medium WQ rating. This suggested that the water obtained from the shallow wells is unsuitable for direct human consumption. It was observed that 100% of the shallow wells were at risk of pollution from onsite sanitation because of their proximity to sanitary facilities. It was strongly recommended that onsite treatment interventions have to be mobilised and initiated to protect the households from further possible consequences of using the water.

Early outbreak detection by linking health advice line calls to water distribution areas retrospectively demonstrated in a large waterborne outbreak of cryptosporidiosis in Sweden.

PubMed

Bjelkmar, Pär; Hansen, Anette; Schönning, Caroline; Bergström, Jakob; Löfdahl, Margareta; Lebbad, Marianne; Wallensten, Anders; Allestam, Görel; Stenmark, Stephan; Lindh, Johan

2017-04-18

In the winter and spring of 2011 a large outbreak of cryptosporidiosis occurred in Skellefteå municipality, Sweden. This study summarizes the outbreak investigation in terms of outbreak size, duration, clinical characteristics, possible source(s) and the potential for earlier detection using calls to a health advice line. The investigation included two epidemiological questionnaires and microbial analysis of samples from patients, water and other environmental sources. In addition, a retrospective study based on phone calls to a health advice line was performed by comparing patterns of phone calls between different water distribution areas. Our analyses showed that approximately 18,500 individuals were affected by a waterborne outbreak of cryptosporidiosis in Skellefteå in 2011. This makes it the second largest outbreak of cryptosporidiosis in Europe to date. Cryptosporidium hominis oocysts of subtype IbA10G2 were found in patient and sewage samples, but not in raw water or in drinking water, and the initial contamination source could not be determined. The outbreak went unnoticed to authorities for several months. The analysis of the calls to the health advice line provides strong indications early in the outbreak that it was linked to a particular water treatment plant. We conclude that an earlier detection of the outbreak by linking calls to a health advice line to water distribution areas could have limited the outbreak substantially.

Online, On Demand Access to Coastal Digital Elevation Models

NASA Astrophysics Data System (ADS)

Long, J.; Bristol, S.; Long, D.; Thompson, S.

2014-12-01

Process-based numerical models for coastal waves, water levels, and sediment transport are initialized with digital elevation models (DEM) constructed by interpolating and merging bathymetric and topographic elevation data. These gridded surfaces must seamlessly span the land-water interface and may cover large regions where the individual raw data sources are collected at widely different spatial and temporal resolutions. In addition, the datasets are collected from different instrument platforms with varying accuracy and may or may not overlap in coverage. The lack of available tools and difficulties in constructing these DEMs lead scientists to 1) rely on previously merged, outdated, or over-smoothed DEMs; 2) discard more recent data that covers only a portion of the DEM domain; and 3) use inconsistent methodologies to generate DEMs. The objective of this work is to address the immediate need of integrating land and water-based elevation data sources and streamline the generation of a seamless data surface that spans the terrestrial-marine boundary. To achieve this, the U.S. Geological Survey (USGS) is developing a web processing service to format and initialize geoprocessing tasks designed to create coastal DEMs. The web processing service is maintained within the USGS ScienceBase data management system and has an associated user interface. Through the map-based interface, users define a geographic region that identifies the bounds of the desired DEM and a time period of interest. This initiates a query for elevation datasets within federal science agency data repositories. A geoprocessing service is then triggered to interpolate, merge, and smooth the data sources creating a DEM based on user-defined configuration parameters. Uncertainty and error estimates for the DEM are also returned by the geoprocessing service. Upon completion, the information management platform provides access to the final gridded data derivative and saves the configuration parameters for future reference. The resulting products and tools developed here could be adapted to future data sources and projects beyond the coastal environment.

Constructed wetlands may lower inorganic nutrient inputs but enhance DOC loadings into a drinking water reservoir in North Wales.

PubMed

Scholz, C; Jones, T G; West, M; Ehbair, A M S; Dunn, C; Freeman, C

2016-09-01

The objective of this study was to monitor a newly constructed wetland (CW) in north Wales, UK, to assess whether it contributes to an improvement in water quality (nutrient removal) of a nearby drinking water reservoir. Inflow and outflow of the Free Water Surface (FWS) CW were monitored on a weekly basis and over a period of 6 months. Physicochemical parameters including pH, conductivity and dissolved oxygen (DO) were measured, as well as nutrients and dissolved organic and inorganic carbon (DOC, DIC) concentration. The CW was seen to contribute to water quality improvement; results show that nutrient removal took place within weeks after construction. It was found that 72 % of initial nitrate (N03 (-)), 53 % of initial phosphate (PO4 (3-)) and 35 % of initial biological oxygen demand (BOD) were removed, calculated as a total over the whole sampling period. From our study, it can be concluded that while inorganic nutrients do decline in CWs, the DOC outputs increases. This may suggest that CWs represent a source for DOC. To assess the carbon in- and output a C budget was calculated.

Evaluating Snowmelt Runoff Processes Using Stable Isotopes in a Permafrost Hillslope

NASA Astrophysics Data System (ADS)

Carey, S. K.

2004-05-01

Conceptual understanding of runoff generation in permafrost regions have been derived primarily from hydrometric information, with isotope and hydrochemical data having only limited application in delineating sources and pathways of water. Furthermore, when stable isotope data are used to infer runoff processes, it often provides conflicting results from hydrometric measurements. In a small subarctic alpine catchment within the Wolf Creek Research Basin, Yukon, Canada, experiments were conducted during the melt period of 2002 and 2003 to trace the stable isotopic signature (d18O) of meltwater from a melting snowpack into permafrost soils and laterally to the stream to identify runoff processes and evaluate sources of error for traditional hydrograph separation studies in snowmelt-dominated permafrost basins. Isotopic variability in the snowpack was recorded at 0.1 m depth intervals during the melt period and compared with the meltwater isotopic signature at the snowpack base collected in lysimeters. Throughout the melt period in both years, there was an isotopic enrichment of meltwater as the season progressed. A downslope transect of wells and piezometers were used to evaluate the influence of infiltrating meltwater and thawing ground on the subsurface d18O signature. As melt began, meltwater infiltrated the frozen porous organic layer, leading to liquid water saturation in the unsaturated pore spaces. Water sampled during this initial melt stage show soil water d18O mirroring that of the meltwater signal. As the melt season progressed, frozen soil began to melt, mixing enriched pre-melt soil water with meltwater. This mixing increased the overall value of d18O obtained from the soil, which gradually increased as thaw progressed. At the end of snowmelt, soil water had a d18O value similar to values from the previous fall, suggesting that much of the initial snowmelt water had been flushed from the hillslope. Results from the hillslope scale are compared with two-component hydrograph separations and sources of error are discussed.

Developing a Small-scale De-fluoridation Filter for use in Rural Northern Ghana with Activated Alumina as the Sorbent

NASA Astrophysics Data System (ADS)

Craig, L.; Stillings, L. L.; Decker, D.; Thomas, J.

2013-12-01

In northern Ghana, groundwater is the main source of household water and is generally considered a safe and economical source of drinking water. However in some areas it contains fluoride (F-) concentrations above the 1.5 ppm limit recommended by the World Health Organization, putting the users at risk of fluorosis. The study area in the Upper East Region of northern Ghana has pockets of groundwater F- up to 4.6 ppm and, as a result, also has a high percentage of residents with dental fluorosis. They have no alternative water source and, because of the poverty and limited access to technology, the affected community lacks the capacity to set up advanced treatment systems. One proposed solution is to attach F- adsorption filters to the wells, since adsorption is considered a simple and cost effective approach for treating high F- drinking water. This study evaluates activated alumina as a sorbent for use in de-fluoridation filters in the study area. We evaluated the long-term adsorption capacity of activated alumina, as well as potential changes in F- adsorption rate and capacity with grain size. We measured differences in positive surface charge (as C m-2) via slow acid titration, as well as F- loading with varied prior hydration time. Experimental results from this research show no notable change in F- adsorption or positive surface charge when the activated alumina surface was pre-equilibrated in distilled water from 24 hours up to 30 weeks before the experiment. The results of F- loading show a maximum of ~3.4 mg F- sorbed per gm activated alumina (at initial pH ~6.9, initial F- 1 to 60 ppm, and 20 hr reaction time). The pH dependent surface charge shows a maximum of ~0.14 C m-2 at pH of ~4.4 and zero surface charge at pH ~8.5. F- loading experiments were conducted with grain size ranges 0.125 to 0.250 mm and 0.5 to 1.0 mm to evaluate changes in F- adsorption rate (initial pH ~6.9, initial F- 10 ppm) and F- loading (initial pH ~6.9, initial F- 1 to 60 ppm, 20 hr reaction time). The F- loading onto activated alumina did not change with grain size. However time to equilibrium increased dramatically with a decrease in grain size - after one hour of reaction time, the larger grain size adsorbed only 59% of F-, while at the finer grain size 90% was adsorbed. Future work will determine the volume of high F- water that can be treated before activated alumina needs to be regenerated or changed. These data will be incorporated into the design of a small-scale F-1 adsorption filter in the study area, and will predict the longevity of activated alumina as the sorbent.

Assimilation of water temperature and discharge data for ensemble water temperature forecasting

NASA Astrophysics Data System (ADS)

Ouellet-Proulx, Sébastien; Chimi Chiadjeu, Olivier; Boucher, Marie-Amélie; St-Hilaire, André

2017-11-01

Recent work demonstrated the value of water temperature forecasts to improve water resources allocation and highlighted the importance of quantifying their uncertainty adequately. In this study, we perform a multisite cascading ensemble assimilation of discharge and water temperature on the Nechako River (Canada) using particle filters. Hydrological and thermal initial conditions were provided to a rainfall-runoff model, coupled to a thermal module, using ensemble meteorological forecasts as inputs to produce 5 day ensemble thermal forecasts. Results show good performances of the particle filters with improvements of the accuracy of initial conditions by more than 65% compared to simulations without data assimilation for both the hydrological and the thermal component. All thermal forecasts returned continuous ranked probability scores under 0.8 °C when using a set of 40 initial conditions and meteorological forecasts comprising 20 members. A greater contribution of the initial conditions to the total uncertainty of the system for 1-dayforecasts is observed (mean ensemble spread = 1.1 °C) compared to meteorological forcings (mean ensemble spread = 0.6 °C). The inclusion of meteorological uncertainty is critical to maintain reliable forecasts and proper ensemble spread for lead times of 2 days and more. This work demonstrates the ability of the particle filters to properly update the initial conditions of a coupled hydrological and thermal model and offers insights regarding the contribution of two major sources of uncertainty to the overall uncertainty in thermal forecasts.

Initial assessment of the ground-water resources in the Monterey Bay region, California

USGS Publications Warehouse

Muir, K.S.

1977-01-01

Because urban growth has placed an increasing demand on the ground-water resources of the Monterey Bay region, Calif., an assessment of the ground-water conditions was made to aid the development of local and regional plans. Ground water provides 80 percent of the water used in the region, which includes six ground-water subbasins. In several of the subbasins, pumpage exceeds safe yield. Existing water-quality degradation results from seawater intrusion, septic-tank effluent, and irrigation-return water. Potential sources of degradation include municipal sewage disposal, leachates from solid-waste disposal sites, and poor-quality connate water. High-priority items for future study include location of recharge areas, detection of seawater intrusion, and well-monitoring of landfill sites. (Woodard-USGS)

Simulation of ground-water flow and land subsidence in the Antelope Valley ground-water basin, California

USGS Publications Warehouse

Leighton, David A.; Phillips, Steven P.

2003-01-01

Antelope Valley, California, is a topographically closed basin in the western part of the Mojave Desert, about 50 miles northeast of Los Angeles. The Antelope Valley ground-water basin is about 940 square miles and is separated from the northern part of Antelope Valley by faults and low-lying hills. Prior to 1972, ground water provided more than 90 percent of the total water supply in the valley; since 1972, it has provided between 50 and 90 percent. Most ground-water pumping in the valley occurs in the Antelope Valley ground-water basin, which includes the rapidly growing cities of Lancaster and Palmdale. Ground-water-level declines of more than 200 feet in some parts of the ground-water basin have resulted in an increase in pumping lifts, reduced well efficiency, and land subsidence of more than 6 feet in some areas. Future urban growth and limits on the supply of imported water may continue to increase reliance on ground water. To better understand the ground-water flow system and to develop a tool to aid in effectively managing the water resources, a numerical model of ground-water flow and land subsidence in the Antelope Valley ground-water basin was developed using old and new geohydrologic information. The ground-water flow system consists of three aquifers: the upper, middle, and lower aquifers. The aquifers, which were identified on the basis of the hydrologic properties, age, and depth of the unconsolidated deposits, consist of gravel, sand, silt, and clay alluvial deposits and clay and silty clay lacustrine deposits. Prior to ground-water development in the valley, recharge was primarily the infiltration of runoff from the surrounding mountains. Ground water flowed from the recharge areas to discharge areas around the playas where it discharged either from the aquifer system as evapotranspiration or from springs. Partial barriers to horizontal ground-water flow, such as faults, have been identified in the ground-water basin. Water-level declines owing to ground-water development have eliminated the natural sources of discharge, and pumping for agricultural and urban uses have become the primary source of discharge from the ground-water system. Infiltration of return flows from agricultural irrigation has become an important source of recharge to the aquifer system. The ground-water flow model of the basin was discretized horizontally into a grid of 43 rows and 60 columns of square cells 1 mile on a side, and vertically into three layers representing the upper, middle, and lower aquifers. Faults that were thought to act as horizontal-flow barriers were simulated in the model. The model was calibrated to simulate steady-state conditions, represented by 1915 water levels and transient-state conditions during 1915-95 using water-level and subsidence data. Initial estimates of the aquifer-system properties and stresses were obtained from a previously published numerical model of the Antelope Valley ground-water basin; estimates also were obtained from recently collected hydrologic data and from results of simulations of ground-water flow and land subsidence models of the Edwards Air Force Base area. Some of these initial estimates were modified during model calibration. Ground-water pumpage for agriculture was estimated on the basis of irrigated crop acreage and crop consumptive-use data. Pumpage for public supply, which is metered, was compiled and entered into a database used for this study. Estimated annual pumpage peaked at 395,000 acre-feet (acre-ft) in 1952 and then declined because of declining agricultural production. Recharge from irrigation-return flows was estimated to be 30 percent of agricultural pumpage; the irrigation-return flows were simulated as recharge to the regional water table 10 years following application at land surface. The annual quantity of natural recharge initially was based on estimates from previous studies. During model calibration, natural recharge was reduced from the initial

Household Effectiveness vs. Laboratory Efficacy of Point-of-use Chlorination

PubMed Central

Levy, Karen; Anderson, Larissa; Robb, Katharine A.; Cevallos, William; Trueba, Gabriel; Eisenberg, Joseph N.S.

2014-01-01

Treatment of water at the household level offers a promising approach to combat the global burden of diarrheal diseases. In particular, chlorination of drinking water has been a widely promoted strategy due to persistence of residual chlorine after initial treatment. However, the degree to which chlorination can reduce microbial levels in a controlled setting (efficacy) or in a household setting (effectiveness) can vary as a function of chlorine characteristics, source water characteristics, and household conditions. To gain more understanding of these factors, we carried out an observational study within households in rural communities of northern coastal Ecuador. We found that the efficacy of chlorine treatment under controlled conditions was significantly better than its effectiveness when evaluated both by ability to meet microbiological safety standards and by log reductions. Water treated with chlorine achieved levels of microbial contamination considered safe for human consumption after 24 hours of storage in the household only 39 – 51% of the time, depending on chlorine treatment regimen. Chlorine treatment would not be considered protective against diarrheal disease according to WHO log reduction standards. Factors that explain the observed compromised effectiveness include: source water turbidity, source water baseline contamination levels, and in-home contamination. Water in 38% of the households that had low turbidity source water (< 10 NTU) met the safe water standard as compared with only 17% of the households that had high turbidity source water (> 10 NTU). A 10 MPN/100mL increase in baseline E. coli levels was associated with a 2.2% increase in failure to meet the E. colistandard. Higher mean microbial contamination levels in 54% of household samples in comparison to their matched controls, which is likely the result of in-home contamination during storage. Container characteristics (size of the container mouth) did not influence chlorine effectiveness. We found no significant differences between chlorine treatment regimens in ability to meet the safe water standards or in overall log reductions, although chlorine dosage did modify the effect of source conditions. These results underscore the importance of measuring both source water and household conditions to determine appropriate chlorine levels, as well as to evaluate the appropriateness of chlorine treatment and other point-of-use water quality improvement interventions. PMID:24561887

Household effectiveness vs. laboratory efficacy of point-of-use chlorination.

PubMed

Levy, Karen; Anderson, Larissa; Robb, Katharine A; Cevallos, William; Trueba, Gabriel; Eisenberg, Joseph N S

2014-05-01

Treatment of water at the household level offers a promising approach to combat the global burden of diarrheal diseases. In particular, chlorination of drinking water has been a widely promoted strategy due to persistence of residual chlorine after initial treatment. However, the degree to which chlorination can reduce microbial levels in a controlled setting (efficacy) or in a household setting (effectiveness) can vary as a function of chlorine characteristics, source water characteristics, and household conditions. To gain more understanding of these factors, we carried out an observational study within households in rural communities of northern coastal Ecuador. We found that the efficacy of chlorine treatment under controlled conditions was significantly better than its household effectiveness when evaluated both by ability to meet microbiological safety standards and by log reductions. Water treated with chlorine achieved levels of microbial contamination considered safe for human consumption after 24 h of storage in the household only 39-51% of the time, depending on chlorine treatment regimen. Chlorine treatment would not be considered protective against diarrheal disease according to WHO log reduction standards. Factors that explain the observed compromised effectiveness include: source water turbidity, source water baseline contamination levels, and in-home contamination. Water in 38% of the households that had low turbidity source water (<10 NTU) met the safe water standard as compared with only 17% of the households that had high turbidity source water (>10 NTU). A 10 MPN/100 mL increase in baseline Escherichia coli levels was associated with a 2.2% increase in failure to meet the E. coli standard. Higher mean microbial contamination levels were seen in 54% of household samples in comparison to their matched controls, which is likely the result of in-home contamination during storage. Container characteristics (size of the container mouth) did not influence chlorine effectiveness. We found no significant differences between chlorine treatment regimens in ability to meet the safe water standards or in overall log reductions, although chlorine dosage did modify the effect of source conditions. These results underscore the importance of measuring both source water and household conditions to determine appropriate chlorine levels, as well as to evaluate the appropriateness of chlorine treatment and other point-of-use water quality improvement interventions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Rainfall-induced runoff from exposed streambed sediments: an important source of water pollution.

PubMed

Frey, S K; Gottschall, N; Wilkes, G; Grégoire, D S; Topp, E; Pintar, K D M; Sunohara, M; Marti, R; Lapen, D R

2015-01-01

When surface water levels decline, exposed streambed sediments can be mobilized and washed into the water course when subjected to erosive rainfall. In this study, rainfall simulations were conducted over exposed sediments along stream banks at four distinct locations in an agriculturally dominated river basin with the objective of quantifying the potential for contaminant loading from these often overlooked runoff source areas. At each location, simulations were performed at three different sites. Nitrogen, phosphorus, sediment, fecal indicator bacteria, pathogenic bacteria, and microbial source tracking (MST) markers were examined in both prerainfall sediments and rainfall-induced runoff water. Runoff generation and sediment mobilization occurred quickly (10-150 s) after rainfall initiation. Temporal trends in runoff concentrations were highly variable within and between locations. Total runoff event loads were considered large for many pollutants considered. For instance, the maximum observed total phosphorus runoff load was on the order of 1.5 kg ha. Results also demonstrate that runoff from exposed sediments can be a source of pathogenic bacteria. spp. and spp. were present in runoff from one and three locations, respectively. Ruminant MST markers were also present in runoff from two locations, one of which hosted pasturing cattle with stream access. Overall, this study demonstrated that rainfall-induced runoff from exposed streambed sediments can be an important source of surface water pollution. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

A Community-Driven Intervention in Tuftonboro, New Hampshire, Succeeds in Altering Water Testing Behavior.

PubMed

Paul, Michael P; Rigrod, Pierce; Wingate, Steve; Borsuk, Mark E

2015-12-01

Maximum contaminant levels created by the U.S. Environmental Protection Agency under the Safe Drinking Water Act do not apply to private wells. Rather, the onus is on individual households to undertake regular water testing. Several barriers exist to testing and treating water from private wells, including a lack of awareness about both well water as a potential source of contaminants and government-recommended water testing schedules; a health literacy level that may not be sufficient to interpret complex environmental health messages; the inconvenience of water testing; the financial costs of testing and treatment; and a myriad of available treatment options. The existence of these barriers is problematic because well water can be a source of hazardous contaminants. This article describes an initiative--undertaken by the Tuftonboro (New Hampshire) Conservation Commission, with support from state agencies and a research program at Dartmouth College--to increase water testing rates in a rural region with a relatively high number of wells. The project prompted more water tests at the state laboratory in one day than in the prior six years. This suggests that community-driven, collaborative efforts to overcome practical barriers could be successful at raising testing rates and ultimately improving public health.

SWMM5 Application Programming Interface and PySWMM: A Python Interfacing Wrapper

EPA Science Inventory

In support of the OpenWaterAnalytics open source initiative, the PySWMM project encompasses the development of a Python interfacing wrapper to SWMM5 with parallel ongoing development of the USEPA Stormwater Management Model (SWMM5) application programming interface (API). ...

Preservation and Significance of Extracellular DNA in Ferruginous Sediments from Lake Towuti, Indonesia

PubMed Central

Vuillemin, Aurèle; Horn, Fabian; Alawi, Mashal; Henny, Cynthia; Wagner, Dirk; Crowe, Sean A.; Kallmeyer, Jens

2017-01-01

Extracellular DNA is ubiquitous in soil and sediment and constitutes a dominant fraction of environmental DNA in aquatic systems. In theory, extracellular DNA is composed of genomic elements persisting at different degrees of preservation produced by processes occurring on land, in the water column and sediment. Extracellular DNA can be taken up as a nutrient source, excreted or degraded by microorganisms, or adsorbed onto mineral matrices, thus potentially preserving information from past environments. To test whether extracellular DNA records lacustrine conditions, we sequentially extracted extracellular and intracellular DNA from anoxic sediments of ferruginous Lake Towuti, Indonesia. We applied 16S rRNA gene Illumina sequencing on both fractions to discriminate exogenous from endogenous sources of extracellular DNA in the sediment. Environmental sequences exclusively found as extracellular DNA in the sediment originated from multiple sources. For instance, Actinobacteria, Verrucomicrobia, and Acidobacteria derived from soils in the catchment. Limited primary productivity in the water column resulted in few sequences of Cyanobacteria in the oxic photic zone, whereas stratification of the water body mainly led to secondary production by aerobic and anaerobic heterotrophs. Chloroflexi and Planctomycetes, the main degraders of sinking organic matter and planktonic sequences at the water-sediment interface, were preferentially preserved during the initial phase of burial. To trace endogenous sources of extracellular DNA, we used relative abundances of taxa in the intracellular DNA to define which microbial populations grow, decline or persist at low density with sediment depth. Cell lysis became an important additional source of extracellular DNA, gradually covering previous genetic assemblages as other microbial genera became more abundant with depth. The use of extracellular DNA as nutrient by active microorganisms led to selective removal of sequences with lowest GC contents. We conclude that extracellular DNA preserved in shallow lacustrine sediments reflects the initial environmental context, but is gradually modified and thereby shifts from its stratigraphic context. Discrimination of exogenous and endogenous sources of extracellular DNA allows simultaneously addressing in-lake and post-depositional processes. In deeper sediments, the accumulation of resting stages and sequences from cell lysis would require stringent extraction and specific primers if ancient DNA is targeted. PMID:28798742

Mantle helium in ground waters of eastern North America: Time and space constraints on sources

USGS Publications Warehouse

Torgersen, T.; Drenkard, S.; Stute, M.; Schlosser, P.; Shapiro, A.

1995-01-01

Mantle helium in continental environments is generally considered to be the result of active volcanism and/or active extension. The latest episodes of volcanism in northeastern North America are the track of the New England hotspot (95–190 Ma) and the closure of the Iapetus sea (before 300 Ma). Thus, the identification of mantle helium in young ground waters of central New England is counter to the conventional wisdom. On the basis of evaluation of helium evolution in emplaced magmas, we postulate an “aged” mantle source for the excess helium component in ground waters of central New England that is either (1) a local, near-surface–emplaced, gas-rich magma that has retained significant volatiles (e.g., in fluid inclusions) or (2) a deeply emplaced gas-rich magma with high initial 2He/4He (10−5) and helium transport (with dispersion) through the crust over time. This gas-rich initial condition may support the concept of a volatile-enriched mantle wedge and thus explain the increased buoyancy flux of the New England hotspot as it traversed eastern North America, as has been suggested by others.

Hydrogen and oxygen isotopic compositions of waters from fumaroles at Kilauea summit, Hawaii

USGS Publications Warehouse

Hinkley, T.K.; Quick, J.E.; Gregory, R.T.; Gerlach, T.M.

1995-01-01

Condensate samples were collected in 1992 from a high-temperature (300?? C) fumarole on the floor of the Halemaumau Pit Crater at Kilauea. The emergence about two years earlier of such a hot fumarole was unprecedented at such a central location at Kilauea. The condensates have hydrogen and oxygen isotopic compositions which indicate that the waters emitted by the fumarole are composed largely of meteoric water, that any magmatic water component must be minor, and that the precipitation that was the original source to the fumarole fell on a recharge area on the slopes of Mauna Loa Volcano to the west. However, the fumarole has no tritium, indicating that it taps a source of water that has been isolated from atmospheric water for at least 40 years. It is noteworthy, considering the unstable tectonic environment and abundant local rainfall of the Kilauea and Mauna Loa regions, that waters which are sources to the hot fumarole remain uncontaminated from atmospheric sources over such long times and long transport distances. As for the common, boiling point fumaroles of the Kilauea summit region, their 18O, D and tritium concentrations indicate that they are dominated by recycling of present day meteoric water. Though the waters of both hot and boiling point fumaroles have dominantly meteoric sources, they seem to be from separate hydrological regimes. Large concentrations of halogens and sulfur species in the condensates, together with the location at the center of the Kilauea summit region and the high temperature, initially suggested that much of the total mass of the emissions of the hot fumarole, including the H2O, might have come directly from a magma body. The results of the present study indicate that it is unreliable to infer a magmatic origin of volcanic waters based solely on halogen or sulfur contents, or other aspects of chemical composition of total condensates. ?? 1995 Springer-Verlag.

Optimization and thermoeconomics research of a large reclaimed water source heat pump system.

PubMed

Zhang, Zi-ping; Du, Fang-hui

2013-01-01

This work describes a large reclaimed water source heat pump system (RWSHPS) and elaborates on the composition of the system and its design principles. According to the characteristics of the reclaimed water and taking into account the initial investment, the project is divided into two stages: the first stage adopts distributed heat pump heating system and the second adopts the combination of centralized and decentralized systems. We analyze the heating capacity of the RWSHPS, when the phase II project is completed, the system can provide hydronic heating water with the supply and return water temperature of 55°C/15°C and meet the hydronic heating demand of 8 million square meters of residential buildings. We make a thermal economics analysis by using Thermal Economics theory on RWSHPS and gas boiler system, it is known that the RWSHPS has more advantages, compared with the gas boiler heating system; both its thermal efficiency and economic efficiency are relatively high. It provides a reference for future applications of the RWSHPS.

Transient Point Infiltration In The Unsaturated Zone

NASA Astrophysics Data System (ADS)

Buecker-Gittel, M.; Mohrlok, U.

The risk assessment of leaking sewer pipes gets more and more important due to urban groundwater management and environmental as well as health safety. This requires the quantification and balancing of transport and transformation processes based on the water flow in the unsaturated zone. The water flow from a single sewer leakage could be described as a point infiltration with time varying hydraulic conditions externally and internally. External variations are caused by the discharge in the sewer pipe as well as the state of the leakage itself. Internal variations are the results of microbiological clogging effects associated with the transformation processes. Technical as well as small scale laboratory experiments were conducted in order to investigate the water transport from an transient point infiltration. From the technical scale experiment there was evidence that the water flow takes place under transient conditions when sewage infiltrates into an unsaturated soil. Whereas the small scale experiments investigated the hydraulics of the water transport and the associated so- lute and particle transport in unsaturated soils in detail. The small scale experiment was a two-dimensional representation of such a point infiltration source where the distributed water transport could be measured by several tensiometers in the soil as well as by a selective measurement of the discharge at the bottom of the experimental setup. Several series of experiments were conducted varying the boundary and initial con- ditions in order to derive the important parameters controlling the infiltration of pure water from the point source. The results showed that there is a significant difference between the infiltration rate in the point source and the discharge rate at the bottom, that could be explained by storage processes due to an outflow resistance at the bottom. This effect is overlayn by a decreasing water content decreases over time correlated with a decreasing infiltration rate. As expected the initial conditions mainly affects the time scale for the water transport. Additionally, the influence of preferential flow paths on the discharge distribution could be found due to the heterogenieties caused by the filling and compaction process of the sandy soil.

Ionospheric Signatures in Radio Occultation Data

NASA Technical Reports Server (NTRS)

Mannucci, Anthony J.; Ao, Chi; Iijima, Byron A.; Kursinkski, E. Robert

2012-01-01

We can extend robustly the radio occultation data record by 6 years (+60%) by developing a singlefrequency processing method for GPS/MET data. We will produce a calibrated data set with profile-byprofile data characterization to determine robust upper bounds on ionospheric bias. Part of an effort to produce a calibrated RO data set addressing other key error sources such as upper boundary initialization. Planned: AIRS-GPS water vapor cross validation (water vapor climatology and trends).

Occurrence of anthropogenic organic compounds and nutrients in source and finished water in the Sioux Falls area, South Dakota, 2009-10

USGS Publications Warehouse

Hoogestraat, Galen K.

2012-01-01

Anthropogenic organic compounds (AOCs) in drinking-water sources commonly are derived from municipal, agricultural, and industrial wastewater sources, and are a concern for water-supply managers. A cooperative study between the city of Sioux Falls, S. Dak., and the U.S. Geological Survey was initiated in 2009 to (1) characterize the occurrence of anthropogenic organic compounds in the source waters (groundwater and surface water) to water supplies in the Sioux Falls area, (2) determine if the compounds detected in the source waters also are present in the finished water, and (3) identify probable sources of nitrate in the Big Sioux River Basin and determine if sources change seasonally or under different hydrologic conditions. This report presents analytical results of water-quality samples collected from source waters and finished waters in the Sioux Falls area. The study approach included the collection of water samples from source and finished waters in the Sioux Falls area for the analyses of AOCs, nutrients, and nitrogen and oxygen isotopes in nitrate. Water-quality constituents monitored in this study were chosen to represent a variety of the contaminants known or suspected to occur within the Big Sioux River Basin, including pesticides, pharmaceuticals, sterols, household and industrial products, polycyclic aromatic hydrocarbons, antibiotics, and hormones. A total of 184 AOCs were monitored, of which 40 AOCs had relevant human-health benchmarks. During 11 sampling visits, 45 AOCs (24 percent) were detected in at least one sample of source or finished water, and 13 AOCs were detected in at least 20 percent of all samples. Concentrations of detected AOCs were all less than 1 microgram per liter, except for two AOCs in multiple samples from the Big Sioux River, and one AOC in finished-water samples. Concentrations of AOCs were less than 0.1 microgram per liter in more than 75 percent of the detections. Nutrient concentrations varied seasonally in source-water samples from surface water and groundwater. In the Big Sioux River, nitrite plus nitrate concentrations were typically less than 1 milligram per liter as nitrogen, and reached a maximum of 4.06 milligrams per liter as nitrogen following a June 2010 storm. Nitrite plus nitrate concentrations in groundwater ranged from less than 0.1 to 0.701 milligram per liter as nitrogen. Eight of the AOCs detected have a human-health benchmark that could be used to evaluate the concentrations in a human-health context. Four AOCs had maximum concentrations within an order of magnitude of the benchmark, indicating that additional monitoring of the compound may be warranted. Three herbicides (atrazine, metolachlor, and prometon) and one degradate (deethylatrazine) were detected in finished-water samples as frequently as in source-water samples. The concentrations of herbicides in source water varied by an order of magnitude from the period of peak use (early summer) to the winter months. Groundwater and finished-water concentrations of atrazine were similar for the six sampling dates when groundwater was the only source water used. Upstream wastewater discharges contributed a fairly small percentage of the flow to the Big Sioux River near Sioux Falls, but several AOCs associated with wastewater were frequently detected. The interpretation of all potential sources of nitrogen cannot be accomplished by use of nitrogen and oxygen isotopes in nitrate alone, but provides a qualitative indication that very little nitrate originates from excess fertilizer runoff, and most nitrate originates from municipal wastewater effluent, manure runoff (either from field application or feeding operations), or fertilizers mineralized by processes in the soil.

Source Water Management for Disinfection By-Product Control using New York City's Operations Support Tool and On-Line Monitoring

NASA Astrophysics Data System (ADS)

Weiss, W. J.; Becker, W.; Schindler, S.

2012-12-01

The United States Environmental Protection Agency's 2006 Stage 2 Disinfectant / Disinfection Byproduct Rule (DBPR) for finished drinking waters is intended to reduce overall DBP levels by limiting the levels of total trihalomethanes (TTHM) and five of the haloacetic acids (HAA5). Under Stage 2, maximum contaminant levels (MCLs), 80 μg/L for TTHM and 60 μg/L for HAA5, are based on a locational running annual average for individual sites instead of as the system-wide quarterly running annual average of the Stage 1 DBPR. This means compliance will have to be met at sampling locations of peak TTHM and HAA5 concentrations rather than an average across the entire system. Compliance monitoring under the Stage 2 DBPR began on April 1, 2012. The New York City (NYC) Department of Environmental Protection (DEP) began evaluating potential impacts of the Stage 2 DBPR on NYC's unfiltered water supply in 2002 by monitoring TTHM and HAA5 levels at various locations throughout the distribution system. Initial monitoring indicated that HAA5 levels could be of concern in the future, with the potential to intermittently violate the Stage 2 DBPR at specific locations, particularly those with high water age. Because of the uncertainty regarding the long-term prospect for compliance, DEP evaluated alternatives to ensure compliance, including operational changes (reducing chlorine dose, changing flow configurations to minimize water age, altering pH, altering source water withdrawals); changing the residual disinfectant from free chlorine to chloramines; and engineered treatment alternatives. This paper will discuss the potential for using DEP's Operations Support Tool (OST) and enhanced reservoir monitoring to support optimization of source water withdrawals to minimize finished water DBP levels. The OST is a state-of-the-art decision support system (DSS) to provide computational and predictive support for water supply operations and planning. It incorporates a water supply system simulation model (OASIS, HydroLogics, Inc.), reservoir water quality models, a near real-time monitoring network, and hydrologic forecasts to provide analytical support for both long-term planning and near-term operations. The OST helps managers and operators balance multiple objectives, including water supply reliability, water quality, and environmental and community release objectives. This paper will describe the results of initial testing to evaluate the potential to reduce DBP levels by managing source water withdrawals to minimize the transport of natural organic matter (NOM) precursors from upper reservoirs. Operating rules were developed that take advantage of selective withdrawal capabilities at some upstate reservoirs and the inherent flexibility of the overall water supply system, seeking to minimize DBPs within the larger framework of water supply, water quality, environmental, and regulatory objectives. The results demonstrated that there is substantial flexibility within the system to manage DBP levels, in some cases providing the potential for reductions of DBP precursors of nearly 10%. Additional research is underway that seeks to better understand the sources of natural organic matter in the NYC watershed to provide guidance for on-line monitoring to be used with the OST to support real-time operation support for DBP control.

Water recycling: a major new initiative for Melbourne--crucial for a sustainable future.

PubMed

Arbon, M; Ireland, M

2003-01-01

Melbourne Water has adopted a challenging target of recycling 20 per cent of treated effluent from Melbourne's two major sewerage treatment plants by 2010. This target was adopted in response to key drivers for water recycling in the Melbourne region such as: strong support for conserving water resources and protecting marine environments; acknowledgment of recycled water as a valuable resource; greater emphasis on environmental issues and sustainable management principles; and opportunities to increase demand for recycled water through effective planning mechanisms. Issues that must be effectively addressed to meet the target include: managing public perceptions of recycled water; health and environmental concerns; lack of consensus among government agencies; high up-front costs of infrastructure; and prices of other sources of water supply not currently true costed. Melbourne Water has identified the following factors as critical in determining the success of recycling strategy: ability to demonstrate that water recycling will be important in terms of long term water cycle management; effective stakeholder consultation; gaining government support; establishing long-term, guaranteed markets for recycled water; implementing well planned, large scale recycling schemes; ability to provide a product that meets customer needs; regulatory approval; and implementation of a system that is economically viable. Water recycling initiatives are being investigated on household, local and regional levels. Over 10 proposals that will contribute to the 20 per cent recycled water target from the regional treatment plants are under various stages of development. Melbourne Water's commitment to recycling within a total water cycle management context is a vital component of this major new initiative for Melbourne and is crucial for a sustainable future.

Propagation of Exploration Seismic Sources in Shallow Water

NASA Astrophysics Data System (ADS)

Diebold, J. B.; Tolstoy, M.; Barton, P. J.; Gulick, S. P.

2006-05-01

The choice of safety radii to mitigation the impact of exploration seismic sources upon marine mammals is typically based on measurement or modeling in deep water. In shallow water environments, rule-of-thumb spreading laws are often used to predict the falloff of amplitude with offset from the source, but actual measurements (or ideally, near-perfect modeling) are still needed to account for the effects of bathymetric changes and subseafloor characteristics. In addition, the question: "how shallow is 'shallow?'" needs an answer. In a cooperative effort by NSF, MMS, NRL, IAGC and L-DEO, a series of seismic source calibration studies was carried out in the Northern Gulf of Mexico during 2003. The sources used were the two-, six-, ten-, twelve-, and twenty-airgun arrays of R/V Ewing, and a 31-element, 3-string "G" gun array, deployed by M/V Kondor, an exploration industry source ship. The results of the Ewing calibrations have been published, documenting results in deep (3200m) and shallow (60m) water. Lengthy analysis of the Kondor results, presented here, suggests an approach to answering the "how shallow is shallow" question. After initially falling off steadily with source-receiver offset, the Kondor levels suddenly increased at a 4km offset. Ray-based modeling with a complex, realistic source, but with a simple homogeneous water column-over-elastic halfspace ocean shows that the observed pattern is chiefly due to geophysical effects, and not focusing within the water column. The same kind of modeling can be used to predict how the amplitudes will change with decreasing water depth, and when deep-water safety radii may need to be increased. Another set of data (see Barton, et al., this session) recorded in 20 meters of water during early 2005, however, shows that simple modeling may be insufficient when the geophysics becomes more complex. In this particular case, the fact that the seafloor was within the near field of the R/V Ewing source array seems to have given rise to seismic phases not normally seen in marine survey data acquired in deeper water. The associated partitioning of energy is likely to have caused the observed uncharacteristically rapid loss of energy with distance. It appears that in this case, the shallow-water marine mammal safety mitigation measures prescribed and followed were far more stringent than they needed to be. A new approach, wherein received levels detected by the towed 6-km multichannel hydrophone array may be used to modify safety radii has recently been proposed, based on these observations.

How clean must our drinking water be: the importance of protective immunity.

PubMed

Frost, Floyd J; Roberts, Melissa; Kunde, Twila R; Craun, Gunther; Tollestrup, Kristine; Harter, Lucy; Muller, Tim

2005-03-01

Cryptosporidium parvum is an important cause of epidemic diarrhea. Few studies have assessed whether serological evidence of prior infection in adults is related to a reduced occurrence of enteric illness. Serum samples and enteric illness event data were obtained in 2000 and 2001 from 326 people served by 1 of 2 unfiltered surface sources or 1 groundwater source. In 2001, filtration was initiated at 1 of the surface sources. Poisson regression related illness episodes with serological responses to the 15/17- and 27-kDa Cryptosporidium antigen groups. Subjects with moderately strong responses to the 15/17-kDa antigen had <65% of the risk of all 1-3-day episodes of diarrheal or gastrointestinal illness and <40% of the risk of all >/=4-day episodes, compared with subjects without a moderately strong response. Water source, change in water treatment, and very weak responses were unrelated to illness events. Endemic Cryptosporidium infections are a common cause of diarrheal and gastrointestinal illness in persons without a moderately strong response to the 15/17-kDa antigen group. Users of surface-derived drinking water are more likely to have strong serological responses to this antigen group and may be at a lower risk of endemic gastrointestinal illness caused by Cryptosporidium infection.

Characterizing large river sounds: Providing context for understanding the environmental effects of noise produced by hydrokinetic turbines

DOE PAGES

Bevelhimer, Mark S.; Deng, Z. Daniel; Scherelis, Constantin C.

2016-01-06

Underwaternoise associated with the installation and operation of hydrokinetic turbines in rivers and tidal zones presents a potential environmental concern for fish and marine mammals. Comparing the spectral quality of sounds emitted by hydrokinetic turbines to natural and other anthropogenic sound sources is an initial step at understanding potential environmental impacts. Underwater recordings were obtained from passing vessels and natural underwater sound sources in static and flowing waters. Static water measurements were taken in a lake with minimal background noise. Flowing water measurements were taken at a previously proposed deployment site for hydrokinetic turbines on the Mississippi River, where soundsmore » created by flowing water are part of all measurements, both natural ambient and anthropogenic sources. Vessel sizes ranged from a small fishing boat with 60 hp outboard motor to an 18-unit barge train being pushed upstream by tugboat. As expected, large vessels with large engines created the highest sound levels, which were, on average, 40 dB greater than the sound created by an operating hydrokinetic turbine. As a result, a comparison of sound levels from the same sources at different distances using both spherical and cylindrical sound attenuation functions suggests that spherical model results more closely approximate observed sound attenuation.« less

Characterizing large river sounds: Providing context for understanding the environmental effects of noise produced by hydrokinetic turbines.

PubMed

Bevelhimer, Mark S; Deng, Z Daniel; Scherelis, Constantin

2016-01-01

Underwater noise associated with the installation and operation of hydrokinetic turbines in rivers and tidal zones presents a potential environmental concern for fish and marine mammals. Comparing the spectral quality of sounds emitted by hydrokinetic turbines to natural and other anthropogenic sound sources is an initial step at understanding potential environmental impacts. Underwater recordings were obtained from passing vessels and natural underwater sound sources in static and flowing waters. Static water measurements were taken in a lake with minimal background noise. Flowing water measurements were taken at a previously proposed deployment site for hydrokinetic turbines on the Mississippi River, where sounds created by flowing water are part of all measurements, both natural ambient and anthropogenic sources. Vessel sizes ranged from a small fishing boat with 60 hp outboard motor to an 18-unit barge train being pushed upstream by tugboat. As expected, large vessels with large engines created the highest sound levels, which were, on average, 40 dB greater than the sound created by an operating hydrokinetic turbine. A comparison of sound levels from the same sources at different distances using both spherical and cylindrical sound attenuation functions suggests that spherical model results more closely approximate observed sound attenuation.

Low-Cost, Robust, and Field Portable Smartphone Platform Photometric Sensor for Fluoride Level Detection in Drinking Water.

PubMed

Hussain, Iftak; Ahamad, Kamal Uddin; Nath, Pabitra

2017-01-03

Groundwater is the major source of drinking water for people living in rural areas of India. Pollutants such as fluoride in groundwater may be present in much higher concentration than the permissible limit. Fluoride does not give any visible coloration to water, and hence, no effort is made to remove or reduce the concentration of this chemical present in drinking water. This may lead to a serious health hazard for those people taking groundwater as their primary source of drinking water. Sophisticated laboratory grade tools such as ion selective electrodes (ISE) and portable spectrophotometers are commercially available for in-field detection of fluoride level in drinking water. However, such tools are generally expensive and require expertise to handle. In this paper, we demonstrate the working of a low cost, robust, and field portable smartphone platform fluoride sensor that can detect and analyze fluoride concentration level in drinking water. For development of the proposed sensor, we utilize the ambient light sensor (ALS) of the smartphone as light intensity detector and its LED flash light as an optical source. An android application "FSense" has been developed which can detect and analyze the fluoride concentration level in water samples. The custom developed application can be used for sharing of in-field sensing data from any remote location to the central water quality monitoring station. We envision that the proposed sensing technique could be useful for initiating a fluoride removal program undertaken by governmental and nongovernmental organizations here in India.

Impact of bromide on halogen incorporation into organic moieties in chlorinated drinking water treatment and distribution systems.

PubMed

Tan, J; Allard, S; Gruchlik, Y; McDonald, S; Joll, C A; Heitz, A

2016-01-15

The impact of elevated bromide concentrations (399 to 750 μg/L) on the formation of halogenated disinfection by-products (DBPs), namely trihalomethanes, haloacetic acids, haloacetonitriles, and adsorbable organic halogen (AOX), in two drinking water systems was investigated. Bromine was the main halogen incorporated into all of the DBP classes and into organic carbon, even though chlorine was present in large excess to maintain a disinfectant residual. Due to the higher reactivity of bromine compared to chlorine, brominated DBPs were rapidly formed, followed by a slower increase in chlorinated DBPs. Higher bromine substitution and incorporation factors for individual DBP classes were observed for the chlorinated water from the groundwater source (lower concentration of dissolved organic carbon (DOC)), which contained a higher concentration of bromide, than for the surface water source (higher DOC). The molar distribution of adsorbable organic bromine to chlorine (AOBr/AOCl) for AOX in the groundwater distribution system was 1.5:1 and almost 1:1 for the surface water system. The measured (regulated) DBPs only accounted for 16 to 33% of the total organic halogen, demonstrating that AOX measurements are essential to provide a full understanding of the formation of halogenated DBPs in drinking waters. In addition, the study demonstrated that a significant proportion (up to 94%) of the bromide in source waters can be converted AOBr. An evaluation of AOBr and AOCl through a second groundwater treatment plant that uses conventional treatment processes for DOC removal produced 70% of AOX as AOBr, with 69% of the initial source water bromide converted to AOBr. Exposure to organobromine compounds is suspected to result in greater adverse health consequences than their chlorinated analogues. Therefore, this study highlights the need for improved methods to selectively reduce the bromide content in source waters. Copyright © 2015 Elsevier B.V. All rights reserved.

Geogenic fluoride and arsenic contamination in the groundwater environments in Tanzania

NASA Astrophysics Data System (ADS)

Bhattacharya, Prosun; Lesafi, Fina; Filemon, Regina; Ligate, Fanuel; Ijumulana, Julian; Mtalo, Felix

2016-04-01

Adequate, safe and accessible drinking water is an important aspect to human health worldwide. Understanding this importance, the Tanzanian Government has initiated a number of programmes to ensure access to high quality water by the citizens. However, elevated concentration of geochemical pollutants in many drinking water sources pose a serious challenge to water suppliers and users in the country. Fluoride is a widespread drinking water contaminant of geogenic origin occuring in both surface- and groundwater around volcanic mountains and many parts within the East African Rift Valley in regions including Arusha (10 mg/L), Shinyanga (2.9 mg/L) and Singida (1.8 mg/L). An estimated 90% of the population living along the Rift Valley region are affected by dental or skeletal fluorosis and bone crippling because of long term exposure to very high levels of fluoride in drinking water sources. In the mining areas within Lake Victoria basin, groundwater wit elevated concentrations of arsenic has been discovered over an extended area. Most of these geochemical and naturally occurring drinking water pollutants are patchy with uncertainities in their spatial and temporal distribution patterns. The adverse health effects of skin disorder and cancer due to an elevated As concentration are reported from the North Mara gold and Geita mining areas in the Lake Victoria basin. About 30% of the water sources used for drinking in Tanzania exceed the WHO guideline values of fluoride (1.5 mg/L) and arsenic (10 μg/L). There is a scarcity of baseline information on the water quality data especially on geogenic contaminants in the groundwater and surface water as potable sources. This information is crucial in exploring sources of safe drinking water aquifers, associated human health risks of fluoride and arsenic pollution. using Laboratory based studies during the past two decades have shown promising results on the removal of fluoride and arsenic using locally available adsorbent materials such as pumice, bauxite, ferralsols and bone char. Developing innovative technologies, pilot-scale implementation and scaling-up water purification based on the locally available adsorbents is thus necessary to safeguard the public health for communities exposed to high levels of fluoride and arsenic in drinking water.

Carbon Cycle Model of a Hawaiian Barrier Reef under Rising Ocean Acidification and Temperature Conditions of the Anthropocene

NASA Astrophysics Data System (ADS)

Drupp, P. S.; Mackenzie, F. T.; De Carlo, E. H.; Guidry, M.

2015-12-01

A CO2-carbonic acid system biogeochemical box model (CRESCAM, Coral Reef and Sediment Carbonate Model) of the barrier reef flat in Kaneohe Bay, Hawai'i was developed to determine how increasing temperature and dissolved inorganic carbon (DIC) content of open ocean source waters, resulting from rising anthropogenic CO2 emissions and ocean acidification, affect the CaCO3budget of coral reef ecosystems. CRESCAM consists of 17 reservoirs and 59 fluxes, including a surface water column domain, a two-layer permeable sediment domain, and a coral framework domain. Physical, chemical, and biological processes such as advection, carbonate precipitation/dissolution, and net ecosystem production and calcification were modeled. The initial model parameters were constrained by experimental and field data from previous coral reef studies, mostly in Kaneohe Bay over the past 50 years. The field studies include data collected by our research group for both the water column and sediment-porewater system.The model system, initially in a quasi-steady state condition estimated for the early 21st century, was perturbed using future projections to the year 2100 of the Anthropocene of atmospheric CO2 ­concentrations, temperature, and source water DIC. These perturbations were derived from the most recent (2013) IPCC's Representative Concentration Pathway (RCP) scenarios, which predict CO2 atmospheric concentrations and temperature anomalies out to 2100. A series of model case studies were also performed whereby one or more parameters (e.g., coral calcification response to declining surface water pH) were altered to investigate potential future outcomes. Our model simulations predict that although the Kaneohe Bay barrier reef will likely see a significant decline in NEC over the coming century, it is unlikely to reach a state of net erosion - a result contrary to several global coral reef model projections. In addition, we show that depending on the future response of NEP and NEC to OA and rising temperatures, the surface waters could switch from being a present-day source of CO2 to the atmosphere to a future sink. This ecosystem specific model can be applied to any reef system where data are available to constrain the initial model state and is a powerful tool for examining future changes in coral reef carbon budgets.

Discovering the Importance of Bi-directional Water Fluxes in Leaves

NASA Astrophysics Data System (ADS)

Kayler, Z. E.; Saurer, M.; Siegwolf, R.

2007-12-01

The stable isotope ratio 18O/16O is used for constraining climate change models, partitioning ecosystem water fluxes and for studies of plant ecophysiology. Leaf water enrichment is an essential starting point for each of these applications. In order to obtain a complete picture of the role leaf water plays, not only the 18O values from leaf water but also the signature of transpired water must be accurately predicted for plants under varying environmental conditions. We used a novel chamber approach using highly depleted water (-330 ‰) as a vapor source to leaves of the velvet bean (Mucuna pruriens). We used a Walz gas exchange system consisting of a chamber that is controlled for humidity, light, and temperature. Water and carbon dioxide fluxes were measured by an infrared gas analyzer and chamber vapor was collected in cold traps chilled to - 60°C. Three leaves were collected after 2 hours to insure isotopic steady-state followed by leaf water extraction and isotope analysis. From this experiment we were able to measure the outward flux of soil source water and the inward flux of ambient vapor over a range of environments that varied in relative humidity (80%, 45%, 20%), light (50, 1000 μmolm-2s-1) and CO2 (50, 800 ppm). Leaf water isotopic values were below the source water values reflecting the influx of the labeled vapor. The degree to which leaf water values were depleted was strongly related to the relative humidity. The Craig-Gordon model overestimated depletion of leaf water under high relative humidity and predictions were improved with the Péclet correction. However, our initial analysis indicates that these models may not fully account for stomatal conductance in predicting leaf water isotopic values.

Effect of topographic characteristics on compound topographic index for identification of gully channel initiation locations

USDA-ARS?s Scientific Manuscript database

Sediment loads from gully erosion can be a significant sediment source within watershed resulting in major contributions to water quality problems, reduction of crop productivity by removal of nutrient rich top soil, and damaging downstream ecosystems. Areas containing a high probability of forming ...

The biophysical link between climate, water, and vegetation in bioenergy agro-ecosystems

USDA-ARS?s Scientific Manuscript database

Land use change for bioenergy feedstocks is likely to intensify as energy demand rises simultaneously with increased pressure to minimize greenhouse gas emissions. Initial assessments of the impact of adopting bioenergy crops as a significant energy source have largely focused on the potential for b...

40 CFR 63.343 - Compliance provisions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... operators of affected sources. (1) Composite mesh-pad systems. (i) During the initial performance test, the... with the emission limitations in § 63.342 through the use of a composite mesh-pad system shall... one performance test and accept ±2 inches of water column from this value as the compliant range. (ii...

40 CFR 63.343 - Compliance provisions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... operators of affected sources. (1) Composite mesh-pad systems. (i) During the initial performance test, the... with the emission limitations in § 63.342 through the use of a composite mesh-pad system shall... one performance test and accept ±2 inches of water column from this value as the compliant range. (ii...

40 CFR 63.343 - Compliance provisions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... operators of affected sources. (1) Composite mesh-pad systems. (i) During the initial performance test, the... with the emission limitations in § 63.342 through the use of a composite mesh-pad system shall... one performance test and accept ±2 inches of water column from this value as the compliant range. (ii...

Predicting Phosphorus Dynamics Across Physiographic Regions Using a Mixed Hortonian Non-Hortonian Hydrology Model

NASA Astrophysics Data System (ADS)

Collick, A.; Easton, Z. M.; Auerbach, D.; Buchanan, B.; Kleinman, P. J. A.; Fuka, D.

2017-12-01

Predicting phosphorus (P) loss from agricultural watersheds depends on accurate representation of the hydrological and chemical processes governing P mobility and transport. In complex landscapes, P predictions are complicated by a broad range of soils with and without restrictive layers, a wide variety of agricultural management, and variable hydrological drivers. The Soil and Water Assessment Tool (SWAT) is a watershed model commonly used to predict runoff and non-point source pollution transport, but is commonly only used with Hortonian (traditional SWAT) or non-Hortonian (SWAT-VSA) initializations. Many shallow soils underlain by a restricting layer commonly generate saturation excess runoff from variable source areas (VSA), which is well represented in a re-conceptualized version, SWAT-VSA. However, many watersheds exhibit traits of both infiltration excess and saturation excess hydrology internally, based on the hydrologic distance from the stream, distribution of soils across the landscape, and characteristics of restricting layers. The objective of this research is to provide an initial look at integrating distributed predictive capabilities that consider both Hortonian and Non-Hortonian solutions simultaneously within a single SWAT-VSA initialization. We compare results from all three conceptual watershed initializations against measured surface runoff and stream P loads and to highlight the model's ability to drive sub-field management of P. All three initializations predict discharge similarly well (daily Nash-Sutcliffe Efficiencies above 0.5), but the new conceptual SWAT-VSA initialization performed best in predicting P export from the watershed, while also identifying critical source areas - those areas generating large runoff and P losses at the sub field level. These results support the use of mixed Hortonian non-Hortonian SWAT-VSA initializations in predicting watershed-scale P losses and identifying critical source areas of P loss in landscapes with VSA hydrology.

Storm water runoff for the Y-12 Plant and selected parking lots

DOE Office of Scientific and Technical Information (OSTI.GOV)

Collins, E.T.

1996-01-01

A comparison of storm water runoff from the Y-12 Plant and selected employee vehicle parking lots to various industry data is provided in this document. This work is an outgrowth of and part of the continuing Non-Point Source Pollution Elimination Project that was initiated in the late 1980s. This project seeks to identify area pollution sources and remediate these areas through the Resource Conservation and Recovery Act/Comprehensive Environmental Response, Compensation, and Liability Act (RCRA/CERCLA) process as managed by the Environmental Restoration Organization staff. This work is also driven by the Clean Water Act Section 402(p) which, in part, deals withmore » establishing a National Pollutant Discharge Elimination System (NPDES) permit for storm water discharges. Storm water data from events occurring in 1988 through 1991 were analyzed in two reports: Feasibility Study for the Best Management Practices to Control Area Source Pollution Derived from Parking Lots at the DOE Y-12 Plant, September 1992, and Feasibility Study of Best Management Practices for Non-Point Source Pollution Control at the Oak Ridge Y-12 Plant, February 1993. These data consisted of analysis of outfalls discharging to upper East Fork Poplar Creek (EFPC) within the confines of the Y-12 Plant (see Appendixes D and E). These reports identified the major characteristics of concern as copper, iron, lead, manganese, mercury, nitrate (as nitrogen), zinc, biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), fecal coliform, and aluminum. Specific sources of these contaminants were not identifiable because flows upstream of outfalls were not sampled. In general, many of these contaminants were a concern in many outfalls. Therefore, separate sampling exercises were executed to assist in identifying (or eliminating) specific suspected sources as areas of concern.« less

Character and dynamics of the Red Sea and Persian Gulf outflows

NASA Astrophysics Data System (ADS)

Bower, Amy S.; Hunt, Heather D.; Price, James F.

2000-03-01

Historical hydrographic data and a numerical plume model are used to investigate the initial transformation, dynamics, and spreading pathways of Red Sea and Persian Gulf outflow waters where they enter the Indian Ocean. The annual mean transport of these outflows is relatively small (<0.4 Sv), but they have a major impact on the hydrographic properties of the Indian Ocean at the thermocline level because of their high salinity. They are different from other outflows in that they flow over very shallow sills (depth < 200 m) into a highly stratified upper ocean environment and they are located at relatively low latitudes (12°N and 26°N). Furthermore, the Red Sea outflow exhibits strong seasonal variability in transport. The four main results of this study are as follows. First, on the basis of observed temperature-salinity (T-S) characteristics of the outflow source and product waters we estimate that the Red Sea and Persian Gulf outflows are diluted by factors of ˜2.5 and 4, respectively, as they descend from sill depth to their depth of neutral buoyancy. The high-dilution factor for the Persian Gulf outflow results from the combined effects of large initial density difference between the outflow source water and oceanic water and low outflow transport. Second, the combination of low latitude and low outflow transport (and associated low outflow thickness) results in Ekman numbers for both outflows that are O(1). This indicates that they should be thought of as frictional density currents modified by rotation rather than geostrophic density currents modified by friction. Third, different mixing histories along the two channels that direct Red Sea outflow water into the open ocean result in product waters with significantly different densities, which probably contributes to the multilayered structure of the Red Sea product waters. In both outflows, seasonal variations in source water and oceanic properties have some effect on the T-S of the product waters, but they have only a minor impact on equilibrium depth. Fourth, product waters from both outflows are advected away from the sill region in narrow boundary currents, at least during part of the year. At other times, the product water appears more in isolated patches.

Design Solutions for the Treatment of DMSD in the ISS Water Recovery System

NASA Technical Reports Server (NTRS)

Perry, Jay; Carter, Donald; Kayatin, Matthew; Bowman, Elizabeth; Gentry, Greg; Muirhead, Brian; Gazda, Daniel; Wilson, Mark

2017-01-01

Dimethylsilanediol (DMSD) has been identified as a problematic organic on ISS. This contaminant was initially identified in the Water Processor Assembly (WPA) product water in 2010 by the Total Organic Carbon Analyzer (TOCA). DMSD is not a crew health hazard at the levels observed in the product water, but it may degrade the performance of the Oxygen Generation System (OGS) which uses the WPA product water for electrolysis and does impact the effective operation of the WPA catalytic reactor. To mitigate these impacts, early replacement of the Multifiltration Beds in the WPA is required. An investigation has determined that the decomposition of atmospheric polydimethylsiloxanes (PDMSs) is the primary source of DMSD in the condensate. PDMSs are prevalent on ISS from a variety of sources, including crew hygiene products, adhesives, caulks, lubricants, and various nonmetallics. These PDMSs also contribute to degradation of the CHX hydrophilic coating, rendering it hydrophobic and therefore affecting its ability to transmit water to the condensate bus. In addition, literature research has determined that PDMSs are likely oxidized to DMSD in the atmosphere when exposed to hydroxyl radicals in the ISS atmosphere. To address these mechanisms, filters have been developed for removal of PDMSs from the ISS atmosphere. However, ongoing analysis indicates a significant reduction in atmospheric PDMSs is required to achieve a measurable reduction of DMSD in the condensate. As a result, additional measures are being pursued to mitigate this issue. First, credible sources are being investigated to quantity to the extent possible the significant sources of PDMSs and identify sources that can be reasonably removed from ISS. Second, a Reverse Osmosis technology is being investigated as an alternate means for removing DMSD from the condensate. This paper summarizes the current status of the overall effort to mitigate DMSD in the US condensate.

CLEANER-Hydrologic Observatory Joint Science Plan

NASA Astrophysics Data System (ADS)

Welty, C.; Dressler, K.; Hooper, R.

2005-12-01

The CLEANER-Hydrologic Observatory* initiative is a distributed network for research on complex environmental systems that focuses on the intersecting water-related issues of both the CUAHSI and CLEANER communities. It emphasizes research on the nation's water resources related to human-dominated natural and built environments. The network will be comprised of: interacting field sites with an integrated cyberinfrastructure; a centralized technical resource staff and management infrastructure to support interdisciplinary research through data collection from advanced sensor systems, data mining and aggregation from multiple sources and databases; cyber-tools for analysis, visualization, and predictive multi-scale modeling that is dynamically driven. As such, the network will transform 21st century workforce development in the water-related intersection of environmental science and engineering, as well as enable substantial educational and engagement opportunities for all age levels. The scientific goal and strategic intent of the CLEANER-Hydrologic Observatory Network is to transform our understanding of the earth's water cycle and associated biogeochemical cycles across spatial and temporal scales-enabling quantitative forecasts of critical water-related processes, especially those that affect and are affected by human activities. This strategy will develop scientific and engineering tools that will enable more effective adaptive approaches for resource management. The need for the network is based on three critical deficiencies in current abilities to understand large-scale environmental processes and thereby develop more effective management strategies. First we lack basic data and the infrastructure to collect them at the needed resolution. Second, we lack the means to integrate data across scales from different media (paper records, electronic worksheets, web-based) and sources (observations, experiments, simulations). Third, we lack sufficiently accurate modeling and decision-support tools to predict the underlying processes or subsequently forecast the effects of different management strategies. Water is a critical driver for the functioning of all ecosystems and development of human society, and it is a key ingredient for the success of industry, agriculture and, national economy. CLEANER-Hydrologic Observatories will foster cutting-edge science and engineering research that addresses major national needs (public and governmental) related to water and include, for example: (i) water resource problems, such as impaired surface waters, contaminated ground water, water availability for human use and ecosystem needs, floods and floodplain management, urban storm water, agricultural runoff, and coastal hypoxia; (ii) understanding environmental impacts on public health; (iii) achieving a balance of economic and environmental sustainability; (iv) reversing environmental degradation; and (v) protecting against chemical and biological threats. CLEANER (Collaborative Large-scale Engineering Analysis Network for Environmental Research) is an ENG initiative; the Hydrologic Observatory Network is GEO initiative through CUAHSI (Consortium of Universities for the Advancement of Hydrologic Science, Inc.). The two initiatives were merged into a joint, bi-directorate program in December 2004.

Initialization and assimilation of cloud and rainwater in a regional model

NASA Technical Reports Server (NTRS)

Raymond, William H.; Olson, William S.

1990-01-01

The initialization and assimilation of cloud and rainwater quantities in a mesoscale regional model was examined. Forecasts of explicit cloud and rainwater are made using conservation equations. The physical processes include condensation, evaporation, autoconversion, accretion, and the removal of rainwater by fallout. These physical processes, some of which are parameterized, represent source and sink in terms in the conservation equations. The question of how to initialize the explicit liquid water calculations in numerical models and how to retain information about precipitation processes during the 4-D assimilation cycle are important issues that are addressed.

Potential Environmental Factors Affecting Oil-Degrading Bacterial Populations in Deep and Surface Waters of the Northern Gulf of Mexico

PubMed Central

Liu, Jiqing; Bacosa, Hernando P.; Liu, Zhanfei

2017-01-01

Understanding bacterial community dynamics as a result of an oil spill is important for predicting the fate of oil released to the environment and developing bioremediation strategies in the Gulf of Mexico. In this study, we aimed to elucidate the roles of temperature, water chemistry (nutrients), and initial bacterial community in selecting oil degraders through a series of incubation experiments. Surface (2 m) and bottom (1537 m) waters, collected near the Deepwater Horizon site, were amended with 200 ppm light Louisiana sweet crude oil and bacterial inoculums from surface or bottom water, and incubated at 4 or 24°C for 50 days. Bacterial community and residual oil were analyzed by pyrosequencing and gas chromatography-mass spectrometry (GC-MS), respectively. The results showed that temperature played a key role in selecting oil-degrading bacteria. Incubation at 4°C favored the development of Cycloclasticus, Pseudoalteromonas, Sulfitobacter, and Reinekea, while 24°C incubations enhanced Oleibacter, Thalassobius, Phaeobacter, and Roseobacter. Water chemistry and the initial community also had potential roles in the development of hydrocarbon-degrading bacterial communities. Pseudoalteromonas, Oleibacter, and Winogradskyella developed well in the nutrient-enriched bottom water, while Reinekea and Thalassobius were favored by low-nutrient surface water. We revealed that the combination of 4°C, crude oil and bottom inoculum was a key factor for the growth of Cycloclasticus, while the combination of surface inoculum and bottom water chemistry was important for the growth of Pseudoalteromonas. Moreover, regardless of the source of inoculum, bottom water at 24°C was a favorable condition for Oleibacter. Redundancy analysis further showed that temperature and initial community explained 57 and 19% of the variation observed, while oil and water chemistry contributed 14 and 10%, respectively. Overall, this study revealed the relative roles of temperature, water chemistry, and initial bacterial community in selecting oil degraders and regulating their evolution in the northern Gulf of Mexico. PMID:28119669

Potential Environmental Factors Affecting Oil-Degrading Bacterial Populations in Deep and Surface Waters of the Northern Gulf of Mexico.

PubMed

Liu, Jiqing; Bacosa, Hernando P; Liu, Zhanfei

2016-01-01

Understanding bacterial community dynamics as a result of an oil spill is important for predicting the fate of oil released to the environment and developing bioremediation strategies in the Gulf of Mexico. In this study, we aimed to elucidate the roles of temperature, water chemistry (nutrients), and initial bacterial community in selecting oil degraders through a series of incubation experiments. Surface (2 m) and bottom (1537 m) waters, collected near the Deepwater Horizon site, were amended with 200 ppm light Louisiana sweet crude oil and bacterial inoculums from surface or bottom water, and incubated at 4 or 24°C for 50 days. Bacterial community and residual oil were analyzed by pyrosequencing and gas chromatography-mass spectrometry (GC-MS), respectively. The results showed that temperature played a key role in selecting oil-degrading bacteria. Incubation at 4°C favored the development of Cycloclasticus, Pseudoalteromonas , Sulfitobacter , and Reinekea , while 24°C incubations enhanced Oleibacter, Thalassobius, Phaeobacter, and Roseobacter. Water chemistry and the initial community also had potential roles in the development of hydrocarbon-degrading bacterial communities. Pseudoalteromonas , Oleibacter , and Winogradskyella developed well in the nutrient-enriched bottom water, while Reinekea and Thalassobius were favored by low-nutrient surface water. We revealed that the combination of 4°C, crude oil and bottom inoculum was a key factor for the growth of Cycloclasticus , while the combination of surface inoculum and bottom water chemistry was important for the growth of Pseudoalteromonas . Moreover, regardless of the source of inoculum, bottom water at 24°C was a favorable condition for Oleibacter. Redundancy analysis further showed that temperature and initial community explained 57 and 19% of the variation observed, while oil and water chemistry contributed 14 and 10%, respectively. Overall, this study revealed the relative roles of temperature, water chemistry, and initial bacterial community in selecting oil degraders and regulating their evolution in the northern Gulf of Mexico.

Benthic nutrient sources to hypereutrophic upper Klamath Lake, Oregon, USA.

PubMed

Kuwabara, James S; Topping, Brent R; Lynch, Dennis D; Carter, James L; Essaid, Hedeff I

2009-03-01

Three collecting trips were coordinated in April, May, and August 2006 to sample the water column and benthos of hypereutrophic Upper Klamath Lake (OR, USA) through the annual cyanophyte bloom of Aphanizomenon flos-aquae. A pore-water profiler was designed and fabricated to obtain the first high-resolution (centimeter-scale) estimates of the vertical concentration gradients of macro- and micronutrients for diffusive-flux determinations. A consistently positive benthic flux for soluble reactive phosphorus (SRP) was observed with solute release from the sediment, ranging between 0.4 and 6.1 mg/m(2)/d. The mass flux over an approximate 200-km(2) lake area was comparable in magnitude to riverine inputs. An additional concern related to fish toxicity was identified when dissolved ammonium also displayed consistently positive benthic fluxes of 4 to 134 mg/m(2)/d, again comparable to riverine inputs. Although phosphorus was a logical initial choice by water quality managers for the limiting nutrient when nitrogen-fixing cyanophytes dominate, initial trace-element results from the lake and major inflowing tributaries suggested that the role of iron limitation on primary productivity should be investigated. Dissolved iron became depleted in the lake water column during the course of the algal bloom, while dissolved ammonium and SRP increased. Elevated macroinvertebrate densities, at least of the order of 10(4) individuals/m(2), suggested that the diffusive-flux estimates may be significantly enhanced by bioturbation. In addition, heat-flux modeling indicated that groundwater advection of nutrients could also significantly contribute to internal nutrient loading. Accurate environmental assessments of lentic systems and reasonable expectations for point-source management require quantitative consideration of internal solute sources.

Social.Water--Open Source Citizen Science Software for CrowdHydrology

NASA Astrophysics Data System (ADS)

Fienen, M. N.; Lowry, C.

2013-12-01

CrowdHydrology is a crowd-sourced citizen science project in which passersby near streams are encouraged to read a gage and send an SMS (text) message with the water level to a number indicated on a sign. The project was initially started using free services such as Google Voice, Gmail, and Google Maps to acquire and present the data on the internet. Social.Water is open-source software, using Python and JavaScript, that automates the acquisition, categorization, and presentation of the data. Open-source objectives pervade both the project and the software as the code is hosted at Github, only free scripting codes are used, and any person or organization can install a gage and join the CrowdHydrology network. In the first year, 10 sites were deployed in upstate New York, USA. In the second year, expansion to 44 sites throughout the upper Midwest USA was achieved. Comparison with official USGS and academic measurements have shown low error rates. Citizen participation varies greatly from site to site, so surveys or other social information is sought for insight into why some sites experience higher rates of participation than others.

Impact of Water Recovery from Wastes on the Lunar Surface Mission Water Balance

NASA Technical Reports Server (NTRS)

Fisher, John W.; Hogan, John Andrew; Wignarajah, Kanapathipi; Pace, Gregory S.

2010-01-01

Future extended lunar surface missions will require extensive recovery of resources to reduce mission costs and enable self-sufficiency. Water is of particular importance due to its potential use for human consumption and hygiene, general cleaning, clothes washing, radiation shielding, cooling for extravehicular activity suits, and oxygen and hydrogen production. Various water sources are inherently present or are generated in lunar surface missions, and subject to recovery. They include: initial water stores, water contained in food, human and other solid wastes, wastewaters and associated brines, ISRU water, and scavenging from residual propellant in landers. This paper presents the results of an analysis of the contribution of water recovery from life support wastes on the overall water balance for lunar surface missions. Water in human wastes, metabolic activity and survival needs are well characterized and dependable figures are available. A detailed life support waste model was developed that summarizes the composition of life support wastes and their water content. Waste processing technologies were reviewed for their potential to recover that water. The recoverable water in waste is a significant contribution to the overall water balance. The value of this contribution is discussed in the context of the other major sources and loses of water. Combined with other analyses these results provide guidance for research and technology development and down-selection.

Investigations into the sources and removal of taste and odor compounds at two treatment facilities on Eastern Lake Erie and Niagara River

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wittmeyer, S.; Cap, R.; Lange, C.

1996-11-01

Taste and odor problems in drinking water supplies have been a topic of research since the early 1900`s. Studies have identified various taste and odor compounds, including methyl-iso-borneol (MIB), geosmin, trichloranisole, and their potential sources, to include the phytoplankton genera Aphanizomenon, Anabaena, Microcystis, and Dinobryon. Many methods of treatment have been investigated to mitigate taste and odors, including the addition of copper sulfate and various chemical oxidants, as well as the introduction of bacteria capable of metabolizing oil-like organic compounds. Taste and odor problems associated with drinking water supplies have become increasingly important, in part because public awareness of watermore » quality issues such as chlorine and associated disinfection byproducts, and the perception that malodorous water may be associated with pathogens such as the infectious Cryptosporidium parvum. Due to marked increases in customer complaints beginning in 1993, and elevated levels of the taste and odor compounds. MIB and geosmin, in eastern Lake Erie and the Niagara River, the Erie County Water Authority (ECWA) initiated an investigation into the impact of MIB and geosmin on water quality, assessment of various means of effective removal, and potential sources.« less

Data visualization, time-series analysis, and mass-balance modeling of hydrologic and water-quality data for the McTier Creek watershed, South Carolina, 2007-2009

USGS Publications Warehouse

Benedict, Stephen T.; Conrads, Paul; Feaster, Toby D.; Journey, Celeste A.; Golden, Heather E.; Knightes, Christopher D.; Davis, Gary M.; Bradley, Paul M.

2012-01-01

The McTier Creek watershed is located in the headwaters of the Edisto River Basin, which is in the Coastal Plain region of South Carolina. The Edisto ecosystem has some of the highest recorded fish-tissue mercury concentrations in the United States. In an effort to advance the understanding of the fate and transport of mercury in stream ecosystems, the U.S. Geological Survey, as part of its National Water-Quality Assessment Program, initiated a field investigation of mercury in the McTier Creek watershed in 2006. The initial efforts of the investigation included the collection of extensive hydrologic and water-quality field data, along with the development of several hydrologic and water-quality models. This series of measured and modeled data forms the primary source of information for this investigation to assess the fate and transport of mercury within the McTier Creek watershed.

Laurentide Ice-Sheet Meltwater Sources to the Gulf of Mexico During the Last Deglaciation: Assessing Data Reconstructions Using Water Isotope Enabled Simulations

NASA Astrophysics Data System (ADS)

Vetter, L.; LeGrande, A. N.; Ullman, D. J.; Carlson, A. E.

2017-12-01

Sediment cores from the Gulf of Mexico show evidence of meltwater derived from the Laurentide Ice Sheet during the last deglaciation. Recent studies using geochemical measurements of individual foraminifera suggest changes in the oxygen isotopic composition of the meltwater as deglaciation proceeded. Here we use the water isotope enabled climate model simulations (NASA GISS ModelE-R) to investigate potential sources of meltwater within the ice sheet. We find that initial melting of the ice sheet from the southern margin contributed an oxygen isotope value reflecting a low-elevation, local precipitation source. As deglacial melting proceeded, meltwater delivered to the Gulf of Mexico had a more negative oxygen isotopic value, which the climate model simulates as being sourced from the high-elevation, high-latitude interior of the ice sheet. This study demonstrates the utility of combining stable isotope analyses with climate model simulations to investigate past changes in the hydrologic cycle.

MSWT-01, flood disaster water treatment solution from common ideas

NASA Astrophysics Data System (ADS)

Ananto, Gamawan; Setiawan, Albertus B.; Z, Darman M.

2013-06-01

Indonesia has a lot of potential flood disaster places with clean water problems faced. Various solution programs always initiated by Government, companies CSR, and people sporadical actions to provide clean water; with their advantages and disadvantages respectively. One solution is easy to operate for instance, but didn't provide adequate capacity, whereas the other had ideal performance but more costly. This situation inspired to develop a water treatment machine that could be an alternative favor. There are many methods could be choosed; whether in simple, middle or high technology, depends on water source input and output result quality. MSWT, Mobile Surface Water Treatment, is an idea for raw water in flood area, basically made for 1m3 per hour. This water treatment design adopted from combined existing technologies and related literatures. Using common ideas, the highlight is how to make such modular process put in compact design elegantly, and would be equipped with mobile feature due to make easier in operational. Through prototype level experiment trials, the machine is capable for producing clean water that suitable for sanitation and cooking/drinking purposes although using contaminated water input source. From the investment point of view, such machine could be also treated as an asset that will be used from time to time when needed, instead of made for project approach only.

Cinnamon Bark, Water Soluble Cinnamon Extract, and Metformin as Initial Treatment for Type 2 Diabetes Mellitus: A Randomized, Controlled Trial

DTIC Science & Technology

2016-12-14

REPORT DOCUMENTATION PAGE Form ApprovedOMB No. 0704-0188 1 . REPORT DATE (DD-MM-YYYY) 2. REPORT TYPE 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER 6...estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the...Cinnamon Extract, and Metformin as Initial Treatment for Type 2 Diabetes Mellitus: A Randomized, Controlled Trial. Paul Crawford, MD Clinical Investigation

Sustainable sanitation and water in small urban centres.

PubMed

Rosemarin, A

2005-01-01

The objective of this paper is to review the global trends in urbanization with respect to availability of adequate sanitation and water supply services. Urbanization is unrelenting and rapid increase in the urban population in the less developed countries is of major global concern regarding this topic of sustainable sanitation and water. Most global urban growth is in the smaller cities and in the developing world. Half the urban developing world lacks adequate water and sanitation. Global urban access to waterborne sanitation is not affordable and thus is not a realistic option so alternative approaches are necessary. The treatment of drinking water cannot be a substitute for sanitation. In order to achieve sustainable sanitation, a change in attitude about human excreta and use of water is required. Essential features of a sustainable sanitation system are: containment, sanitisation and recycling. To improve water supply, we need to improve management practices, use full-cost pricing, introduce watershed approaches to protection and provide improved sanitation. Small urban initiatives need to go beyond the traditional sectors and new initiatives are required like on-site urban ecostations, source-separation of urine and faeces, decentralised greywater treatment and integration of sanitation into the cost of housing.

Alternative Options for Safe Drinking Water in Arsenic and Salinity Affected Bornal-Iliasabad Union of Kalia Upazila, Narail District, Bangladesh

NASA Astrophysics Data System (ADS)

Rahman, M. M.; Hasan, M. A.; Ahmed, K. M.; Nawrin, N.

2016-12-01

The study area, Bornal-Ilisabad union, Kalia, Narail is one of the most vulnerable areas of Bangladesh in terms of access to safe drinking water. Shallow groundwater of this area is highly arsenic contaminated (mostly >500 μg/L) and deep groundwater is saline (EC ranges 1 to 8 mS/cm). Local communities rely on rainwater for drinking and cooking purposes during the monsoon and rest of the year they use surface water from pond which are mostly polluted. In areas where surface water is not available people are compelled to use arsenic contaminated groundwater and thus exposing themselves to serious health hazard. Principal objective of the research is to evaluate the effectiveness of managed aquifer recharge (MAR) and subsurface arsenic removal (SAR) technology in mitigating groundwater salinity and arsenic, to provide alternative sources of safe water. Surface water (pond water) and rainwater collected from roof top are used as source water to be recharged into the target aquifer for the MAR system. Source water is filtered through a sand filtration unit to remove turbidity and microorganisms before recharging through infiltration wells. For SAR system, on the other hand, a certain volume (2000L) of groundwater is abstracted from the target aquifer and then aerated for about half an hour to saturate with oxygen. The oxygenated water is injected into the aquifer and kept there for 6-8 hours and then abstracted for use. The MAR system constructed in the study area is found very effective in reducing groundwater salinity. The electrical conductivity (EC) of the groundwater of MAR system has been reduced 72-81% from the initial EC value of 3.4 mS/cm. A significant improvement in groundwater arsenic and iron concentration is also observed. The system is yielding groundwater with arsenic within permissible limit of Bangladesh drinking water standard (50 μg/L) which was 100 μg/L before introduction of MAR system. The SAR system is also found effective in reducing groundwater arsenic below 50 μg/L form the initial concentration of 100 μg/L. The system is now capable of yielding about 1500L of low arsenic and low iron concentrated water per cycle injection of aerated water which is 70- 80% of the injected volume (2000L). Alternative technology MAR and SAR can be applied extensively in the study area for improving safe water access.

Improving water quality through California's Clean Beach Initiative: an assessment of 17 projects.

PubMed

Dorsey, John H

2010-07-01

California's Clean Beach Initiative (CBI) funds projects to reduce loads of fecal indicator bacteria (FIB) impacting beaches, thus providing an opportunity to judge the effectiveness of various CBI water pollution control strategies. Seventeen initial projects were selected for assessment to determine their effectiveness on reducing FIB in the receiving waters along beaches nearest to the projects. Control strategies included low-flow diversions, sterilization facilities, sewer improvements, pier best management practices (BMPs), vegetative swales, and enclosed beach BMPs. Assessments were based on statistical changes in pre- and postproject mean densities of FIB at shoreline monitoring stations targeted by the projects. Most low-flow diversions and the wetland swale project were effective in removing all contaminated runoff from beaches. UV sterilization was effective when coupled with pretreatment filtration and where effluent was released within a few hundred meters of the beach to avoid FIB regrowth. Other BMPs were less effective because they treated only a portion of contaminant sources impacting their target beach. These findings should be useful to other coastal states and agencies faced with similar pollution control problems.

Seasonal reversal at Miryang Eoreumgol (Ice Valley), Korea: observation and monitoring

NASA Astrophysics Data System (ADS)

Byun, Hi-Ryong; Tanaka, Hiroshi L.; Choi, Pom-Yong; Kim, Do-Woo

2011-12-01

We investigate an anomalous phenomenon evident in the Miryang Eoreumgol (Ice Valley), Korea: The wind and water are cold during summer and warm during winter, and ice formation does not occur in winter but in summer. We have initiated observations and investigations into the origin of heat sources particularly with regard to the mechanism of ice formation in summer. Previous theories, e.g., concerning underground gravity currents, water evaporation, diurnal and seasonal respirations of the talus, effects of ground heat, radiation and topography, etc., are considered. After a calculation of heat sources, we propose two new concepts—a repetitious heat separation mechanism and a positive feedback mechanism of cold air generation—to demonstrate that the heat mechanism of the seasonal reversal of the ice valley may be controlled by the use of the phase change between ice and water vapor with only a small amount of additional unknown energy.

A systems approach to water recovery testing for space life support - Initial biomedical results from the ECLSS Water Recovery Test and plans for testbed utilization

NASA Technical Reports Server (NTRS)

Aten, Laurie A.; Crump, William J.; Sauer, Richard L.

1992-01-01

Among the challenges of designing and constructing Space Station Freedom is the development of the water system. A review of past efforts in reclaiming waste water in enclosed environments reveals that there are many gaps in the biomedical understanding of this process. Some of the key uncertainties of human interaction with a closed water system include determining potential contaminants and establishing safe levels of multiple compounds in the enclosed system of Space Station. Another uncertainty is the microbial constituency of such a system and what impact it could have on crew health and performance. The use of iodine as the passive biocide may have both an indirect and direct impact on the crew. In this paper the initial results of the Water Recovery Test are reviewed from a biomedical perspective, revealing areas where more information is needed to develop the ECLSS water system. By including the approach of 'man as a subsystem', consideration is given to how man interacts with the total water system. Taking this systems approach to providing the crew with a safe source of water gives useful insight into the most efficient design and utilization of closed system testbeds.

Evidence for Central Venous Pressure Resetting During Initial Exposure to Microgravity

DTIC Science & Technology

2001-12-01

to 10° HDT. During each experimental condition, water and food were provided ad libitum and intake amounts were recorded. A standard monkey diet ...biscuit (LabDiet) of ;3.5 g with a caloric density equal to 4 kcal/g (69% carbohy- drate, 13% fat, 18% protein) was used as the primary food source...effect of Dextran on water filtration from renal tubules to tubular capillar- ies, consequently reducing urine formation in a hypo - volemic state of HDT

Managing variability in decision making in swine growing-finishing units.

PubMed

Agostini, Piero da Silva; Manzanilla, Edgar Garcia; de Blas, Carlos; Fahey, Alan G; da Silva, Caio Abercio; Gasa, Josep

2015-01-01

Analysis of data collected from pig farms may be useful to understand factors affecting pig health and productive performance. However, obtaining these data and drawing conclusions from them can be done at different levels and presents several challenges. In the present study, information from 688 batches of growing-finishing (GF) pigs (average initial and final body weight of 19.1 and 108.5 kg respectively) from 404 GF farms integrated in 7 companies was obtained between July 2008 and July 2010 in Spain by survey. Management and facility factors associated with feed conversion ratio (FCR) and mortality were studied by multiple linear regression analysis in each single company (A to G) and in an overall database (OD). Factors studied were geographic location of the farm, trimester the pigs entered the farm, breed of sire and sex segregation in pens (BREGENSEG), use of circovirus vaccine, number of origins the pigs were obtained from, age of the farm, percentage of slatted floor, type of feeder, drinker and ventilation, number of phases and form of feed, antibiotic administration system, water source, and number and initial weight of pigs. In two or more companies studied and/or in OD, the trimester when pigs were placed in the farm, BREGENSEG, number of origins of the pigs, age of the farm and initial body weight were factors associated with FCR. Regarding mortality, trimester of placement, number of origins of the pigs, water source in the farm, number of pigs placed and the initial body weight were relevant factors. Age of the farm, antibiotic administration system, and water source were only provided by some of the studied companies and were not included in the OD model, however, when analyzed in particular companies these three variables had an important effect and may be variables of interest in companies that do not record them. Analysing data collected from farms at different levels helps better understand factors associated with productive performance of pig herds. Out of the studied factors trimester of placement and number of origins of the pigs were the most relevant factors associated with FCR and mortality.

Optimization and Thermoeconomics Research of a Large Reclaimed Water Source Heat Pump System

PubMed Central

Zhang, Zi-ping; Du, Fang-hui

2013-01-01

This work describes a large reclaimed water source heat pump system (RWSHPS) and elaborates on the composition of the system and its design principles. According to the characteristics of the reclaimed water and taking into account the initial investment, the project is divided into two stages: the first stage adopts distributed heat pump heating system and the second adopts the combination of centralized and decentralized systems. We analyze the heating capacity of the RWSHPS, when the phase II project is completed, the system can provide hydronic heating water with the supply and return water temperature of 55°C/15°C and meet the hydronic heating demand of 8 million square meters of residential buildings. We make a thermal economics analysis by using Thermal Economics theory on RWSHPS and gas boiler system, it is known that the RWSHPS has more advantages, compared with the gas boiler heating system; both its thermal efficiency and economic efficiency are relatively high. It provides a reference for future applications of the RWSHPS. PMID:24089607

SYNTHESIS AND MUTAGENIC PROPERTIES OF 4,4'-DIAMINO-PARA-TERPHENYL AND 4,4'-DIAMINO-PARA-QUATERPHENYL

EPA Science Inventory

DBPs in drinking water can be controlled by the type of treatment and by knowing andd controlling major sources of DBP toxicant precursors and toxicants that "evade" treatment processes. Efforts are being directed at one category at a time. The initial precursor categories to be ...

Use of modified pine bark for removal of pesticides from stormwater runoff

Treesearch

Mandla A. Tshabalala

2003-01-01

Pesticide entrainment in stormwater runoff can contribute to non-point source pollution of surface waters. Granular activated carbon has been successfully used for removing pesticides from wastewater. However, implementation of granular activated carbon sorption media in stormwater filtration systems comes with high initial capital investment and operating costs....

Occurrence of anthropogenic organic compounds in ground water and finished water of community water systems in Eagle and Spanish Springs Valleys, Nevada, 2002-2004

USGS Publications Warehouse

Rosen, Michael R.; Shaefer, Donald H.; Toccalino, Patricia A.; Delzer, Gregory C.

2006-01-01

As a part of the U.S. Geological Survey's National Water-Quality Assessment Program, an effort to characterize the quality of major rivers and aquifers used as a source of supply to some of the largest community water systems (CWSs) in the United States has been initiated. These studies, termed Source Water-Quality Assessments (SWQAs), consist of two sampling phases. Phase 1 was designed to determine the frequency of detection and concentrations of about 260 volatile organic compounds (VOCs), pesticides and pesticide degradates, and other anthropogenic organic compounds in source water of 15 CWS wells in each study. Phase 2 monitors concentrations in the source water and also the associated finished water of CWSs for compounds most frequently detected during phase 1. One SWQA was completed in the Nevada Basin and Range area in Nevada. Ten CWS wells in Eagle Valley and five CWS wells in Spanish Springs Valley were sampled. For phase 2, two wells were resampled in Eagle Valley. Samples were collected during 2002-2004 for both phases. Water use in Eagle Valley is primarily for domestic purposes and is supplied through CWSs. Ground-water sources provide about 55 percent of the public-water supply, and surface-water sources supply about 45 percent. Lesser amounts of water are provided by domestic wells. Very little water is used for agriculture or manufacturing. Spanish Springs Valley has water-use characteristics similar to those in Eagle Valley, although there is more agricultural water use in Spanish Springs Valley than in Eagle Valley. Maximum contaminant concentrations were compared to two human-health benchmarks, if available, to describe the water-quality data in a human-health context for these findings. Measured concentrations of regulated contaminants were compared to U.S. Environmental Protection Agency and Nevada Maximum Contaminant Level (MCL) values. Measured concentrations of unregulated contaminants were compared to Health-Based Screening Levels, which are not regulatory standards and are not legally enforceable values. All of the contaminants detected in this study were found at concentrations less than available human-health benchmarks. In the source waters sampled in phase 1, 10 contaminants of the approximately 260 measured were detected in samples collected from Eagle Valley, and 4 contaminants were detected in samples from Spanish Springs Valley. The most frequently detected compounds in the Eagle Valley source water were chloroform (a disinfection by-product), which was detected in samples from four wells, and deethylatrazine (a degradation product of the herbicide atrazine), which was detected in samples from three wells. Each of the four contaminants detected in the Spanish Springs Valley source waters was detected in samples from one well. The detection frequencies of VOCs and pesticides in samples from the SWQA wells were similar to those in samples from both shallow and deep monitoring wells in Carson City, Reno, and Spanish Springs. This indicates that the SWQA sampling is representative of the organic chemical compounds likely to be detected in the aquifers sampled. However, more organic compounds were detected at low frequencies and concentrations in samples from the monitoring wells than in samples from SWQA wells. Three contaminants were detected in one finished-water sample collected from Eagle Valley. Comparison of SWQA results in the Nevada Basin and Range Study Unit to results of an SWQA in the larger urban area of Salt Lake City showed that fewer anthropogenic compounds were detected in Eagle and Spanish Springs Valleys and generally at lower concentrations than in the Salt Lake City study.

Transport of lincomycin to surface and ground water from manure-amended cropland.

PubMed

Kuchta, Sandra L; Cessna, Allan J; Elliott, Jane A; Peru, Kerry M; Headley, John V

2009-01-01

Livestock manure containing antimicrobials becomes a possible source of these compounds to surface and ground waters when applied to cropland as a nutrient source. The potential for transport of the veterinary antimicrobial lincomycin to surface waters via surface runoff and to leach to ground water was assessed by monitoring manure-amended soil, simulated rainfall runoff, snowmelt runoff, and ground water over a 2-yr period in Saskatchewan, Canada, after fall application of liquid swine manure to cropland. Liquid chromatography tandem mass spectrometry was used to quantify lincomycin in all matrix extracts. Initial concentrations in soil (46.3-117 mug kg(-1)) were not significantly different (p > 0.05) for manure application rates ranging from 60,000 to 95,000 L ha(-1) and had decreased to nondetectable levels by mid-summer the following year. After fall manure application, lincomycin was present in all simulated rainfall runoff (0.07-2.7 mug L(-1)) and all snowmelt runoff (0.038-3.2 mug L(-1)) samples. Concentrations in snowmelt runoff were not significantly different from those in simulated rainfall runoff the previous fall. On average, lincomycin concentrations in ephemeral wetlands dissipated by 50% after 31 d. Concentrations of lincomycin in ground water were generally <0.005 mug L(-1). This study demonstrates that the management practice of using livestock manure from confined animal feeding operations as a plant nutrient source on cropland may result in antimicrobial transport to surface and ground waters.

Implications of salinity pollution hotspots on agricultural production

NASA Astrophysics Data System (ADS)

Floerke, Martina; Fink, Julia; Malsy, Marcus; Voelker, Jeanette; Alcamo, Joseph

2016-04-01

Salinity pollution can have many negative impacts on water resources used for drinking, irrigation, and industrial purposes. Elevated concentrations of salinity in irrigation water can lead to decreased crop production or crop death and, thus, causing an economic problem. Overall, salinity pollution is a global problem but tends to be more severe in arid and semi-arid regions where the dilution capacity of rivers and lakes is lower and the use of irrigation higher. Particularly in these regions agricultural production is exposed to high salinity of irrigation water as insufficient water quality further reduces the available freshwater resources. According to the FAO, irrigated agriculture contributes about 40 percent of the total food production globally, and therefore, high salinity pollution poses a major concern for food production and food security. We use the WaterGAP3 modeling framework to simulate hydrological, water use, and water quality conditions on a global scale for the time period 1990 to 2010. The modeling framework is applied to simulate total dissolved solids (TDS) loadings and in-stream concentrations from different point and diffuse sources to get an insight on potential environmental impacts as well as risks to agricultural food production. The model was tested and calibrated against observed data from GEMStat and literature sources. Although global in scope, the focus of this study is on developing countries, i.e., in Africa, Asia, and Latin America, as these are most threatened by salinity pollution. Furthermore, insufficient water quality for irrigation and therefore restrictions in irrigation water use are examined, indicating limitations to crop production. Our results show that elevated salinity concentrations in surface waters mainly occur in peak irrigation regions as irrigated agriculture is not only the most relevant water use sector contributing to water abstractions, but also the dominant source of salinity pollution. Additionally, large metropolitan regions are initially loading hotspots and pollution, too, and prevention becomes important as point sources are dependent on sewer connection rates and treatment levels. In conclusion, this study provides a detailed picture of the spatial and temporal distribution of salinity pollution and identifies hotspot areas as well as the dominant sources. Furthermore, impacts of water quality degradation on agricultural production and food security are quantified, which aim for a better understanding of the risks for food security caused by water quality impairment.

Investigating the Sources of Decadal-Scale Property Changes in Antarctic Bottom Water in the Southeast Indian Ocean (80-90°E)

NASA Astrophysics Data System (ADS)

Gottschalk, K.; Macdonald, A. M.

2016-12-01

A recognizable warming and freshening of Antarctic Bottom Water (AABW) throughout much of the Southern Ocean is one of the major findings of the international long-line hydrographic programs of 1990's and the 2000's. A recent GO-SHIP repeat of the I08S line in the southeast Indian Ocean in 2016 found continued, but weaker, AABW warming and significantly strong freshening in the Antarctic-Australian Basin (A-AB). It has been proposed that the 2010 B9b iceberg calving along the Adélie Land Coast may be linked to the sharp increase in A-AB AABW freshening. The present study seeks to affirm or challenge this hypothesis through a quantitative investigation into the origins of A-AB (i.e. I08S) bottom water. The investigation takes the form of an Extended Optimum MultiParameter mixing analysis (eOMP) to determine a) the contribution of individual formation regions to the bottom water seen at I08S, and b) how these contributions may have changed over the twenty years since the first occupation of the line. The initial investigation that used mean source water properties found Adélie Bottom Water (ADLBW) to be the dominant source of AABW in the A-AB. However, by calculating source water properties from times preceding the occupations of the I08S line (1994, 2007, 2016), it was determined that in both 1994 and 2007, Ross Sea Bottom Water (RSBW) was the dominant source of AABW (approx. 61 & 75 %, respectively) in the A-AB. This dominance shifted in 2016, to ADLBW composing approximately 44% of AABW. This result suggests that it is feasible that the B9b calving that impacted ADLBW in the formation region is, at least, partially responsible for the changes seen at I08S. Nevertheless, given that there are significant contributions from both RSBW and Weddell Sea Bottom Water, it seems unlikely that this single alteration of ADLBW is the sole driver of the observed freshening. Further investigation seeks to determine the sensitivity of the solution to particular source water definitions and to the specific property budgets used to constrain the system.

Beachrock morphology and genesis on a paraglacial beach

NASA Astrophysics Data System (ADS)

Cooper, J. A. G.; Green, A. N.; Wiles, E. A.

2017-10-01

Beachrock is present in deep, stable sections of a mixed sand and gravel beach at Whitepark Bay (55o14‧N) on the paraglacial coast of Northern Ireland. The beachrock was revealed following progressive and extreme beach erosion during two particularly stormy winters (2013/14 and 2014/15). It occurs as large (up to 1 m diameter, 0.2 m thick), rounded, disc-shaped concretions in which original beach bedding structures are preserved. Both sand and gravel beach facies are cemented. The cements are similar to those of tropical beachrocks and comprise an initial thin micrite rim, and subsequent grain rims of aragonitic needles. The cementation is attributed to saturation of beach groundwater with calcium carbonate sourced from adjacent Cretaceous chalk outcrop in cliffs behind the beach and dunes. The micrite rims suggest microbial activity in the initial cementation, possibly by scavenging from chalk and skeletal carbonate grains. Subsequent aragonite rims were formed through degassing of CO2 aided by tidal water level fluctuations. Despite similar cementation processes to low latitude beachrocks, only isolated concretions occur rather than extensive shore-parallel outcrops. Conditions necessary for cementation (and ultimately preservation) in this cold temperate and paraglacial setting include long-term beach stability, a carbonate source (in this case, adjacent chalk cliffs and stream sapping) and tidal water level fluctuations. Bacterial activity may initiate calcite precipitation. Following extreme storms and with progressive shoreline retreat prompted by rising sea levels, increased reporting of cold-water beachrocks is to be expected as formerly stable sections of beaches are exposed to wave action.

New formulations for tsunami runup estimation

NASA Astrophysics Data System (ADS)

Kanoglu, U.; Aydin, B.; Ceylan, N.

2017-12-01

We evaluate shoreline motion and maximum runup in two folds: One, we use linear shallow water-wave equations over a sloping beach and solve as initial-boundary value problem similar to the nonlinear solution of Aydın and Kanoglu (2017, Pure Appl. Geophys., https://doi.org/10.1007/s00024-017-1508-z). Methodology we present here is simple; it involves eigenfunction expansion and, hence, avoids integral transform techniques. We then use several different types of initial wave profiles with and without initial velocity, estimate shoreline properties and confirm classical runup invariance between linear and nonlinear theories. Two, we use the nonlinear shallow water-wave solution of Kanoglu (2004, J. Fluid Mech. 513, 363-372) to estimate maximum runup. Kanoglu (2004) presented a simple integral solution for the nonlinear shallow water-wave equations using the classical Carrier and Greenspan transformation, and further extended shoreline position and velocity to a simpler integral formulation. In addition, Tinti and Tonini (2005, J. Fluid Mech. 535, 33-64) defined initial condition in a very convenient form for near-shore events. We use Tinti and Tonini (2005) type initial condition in Kanoglu's (2004) shoreline integral solution, which leads further simplified estimates for shoreline position and velocity, i.e. algebraic relation. We then use this algebraic runup estimate to investigate effect of earthquake source parameters on maximum runup and present results similar to Sepulveda and Liu (2016, Coast. Eng. 112, 57-68).

Inorganic Geochemistry of Flowback Water from the Montney Formation: Potential Sources of Elevated Ion Concentrations

NASA Astrophysics Data System (ADS)

Owen, J.; Bustin, R.

2016-12-01

An inorganic geochemical analysis was conducted on flowback water from hydraulically fractured oil and gas wells of the Montney Formation of varying thermal maturity and stratigraphy in the Western Canadian Sedimentary Basin. The results of this study provide insight into potential sources of the elevated ion concentrations and can be used to assist with wastewater management and blending of water for reuse. Samples were obtained from 31 wells across the Montney and include wells completed in the lower, middle, and upper units. Selected fluid samples from each well were analyzed using ICP-OES, ICP-MS, and IC. Oxygen and hydrogen isotope analysis was performed using a liquid-water isotope analyzer. The flowback waters are classified as sodium-chloride type. In addition to Na and Cl, calcium, potassium, magnesium, and strontium are elevated and increase during the flowback period. Barium, iron, and lithium are also elevated at some locations. The early flowback water chemistry varies within the formation: higher initial TDS values of approximately 50,000mg/L in Upper Montney flowback water relative to the initial TDS from both Middle and Lower Montney wells (<25,000mg/L and <15,000mg/L, respectively). However, overall, the maximum TDS attained later in the flowback period does not show a consistent stratigraphic trend (range: 55,000 - 130,000mg/L) except for one region in the Middle Montney where the maximum TDS remains consistently lower than other areas (<50,000mg/L). Barium is notable in Montney flowback due to its high variability, with the lowest concentrations occurring in Middle Montney flowback and the highest in Lower Montney flowback. Comparing closely spaced wells completed on the same pad and in the same zone, the flowback waters generally have similar ion concentrations and consistent ion ratios. The increasing ion concentrations as well as the stable water isotopes support mixing between the hydraulic fracturing fluid, which has relatively low ion concentrations, and more saline connate formation water. Geochemical modeling indicates the ion concentrations in the flowback water are a complex product of mineral precipitation/dissolution, ion exchange with the reservoir, geochemistry of the connate water and water saturation of the reservoir.

Sequence-based analysis of the microbial composition of water kefir from multiple sources.

PubMed

Marsh, Alan J; O'Sullivan, Orla; Hill, Colin; Ross, R Paul; Cotter, Paul D

2013-11-01

Water kefir is a water-sucrose-based beverage, fermented by a symbiosis of bacteria and yeast to produce a final product that is lightly carbonated, acidic and that has a low alcohol percentage. The microorganisms present in water kefir are introduced via water kefir grains, which consist of a polysaccharide matrix in which the microorganisms are embedded. We aimed to provide a comprehensive sequencing-based analysis of the bacterial population of water kefir beverages and grains, while providing an initial insight into the corresponding fungal population. To facilitate this objective, four water kefirs were sourced from the UK, Canada and the United States. Culture-independent, high-throughput, sequencing-based analyses revealed that the bacterial fraction of each water kefir and grain was dominated by Zymomonas, an ethanol-producing bacterium, which has not previously been detected at such a scale. The other genera detected were representatives of the lactic acid bacteria and acetic acid bacteria. Our analysis of the fungal component established that it was comprised of the genera Dekkera, Hanseniaspora, Saccharomyces, Zygosaccharomyces, Torulaspora and Lachancea. This information will assist in the ultimate identification of the microorganisms responsible for the potentially health-promoting attributes of these beverages. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Surface engineered nanoparticles for improved surface enhanced Raman scattering applications and method for preparing same

DOEpatents

Simmons, Blake A [San Francisco, CA; Talin, Albert Alec [Livermore, CA

2009-11-27

A method for producing metal nanoparticles that when associated with an analyte material will generate an amplified SERS spectrum when the analyte material is illuminated by a light source and a spectrum is recorded. The method for preparing the metal nanoparticles comprises the steps of (i) forming a water-in-oil microemulsion comprising a bulk oil phase, a dilute water phase, and one or more surfactants, wherein the water phase comprises a transition metal ion; (ii) adding an aqueous solution comprising a mild reducing agent to the water-in-oil microemulsion; (iii) stirring the water-in-oil microemulsion and aqueous solution to initiate a reduction reaction resulting in the formation of a fine precipitate dispersed in the water-in-oil microemulsion; and (iv) separating the precipitate from the water-in-oil microemulsion.

Membrane Based Thermal Control Development

NASA Technical Reports Server (NTRS)

Murdoch, Karen

1997-01-01

The investigation of the feasibility of using a membrane device as a water boiler for thermal control is reported. The membrane device permits water vapor to escape to the vacuum of space but prevents the loss of liquid water. The vaporization of the water provides cooling to the water loop. This type of cooling device would have application for various types of short duration cooling needs where expenditure of water is allowed and a low pressure source is available such as in space or on a planet's surface. A variety of membrane samples, both hydrophilic and hydrophobic, were purchased to test for this thermal control application. An initial screening test determined if the membrane could pose a sufficient barrier to maintain water against vacuum. Further testing compared the heat transfer performance of those membranes that passed the screening test.

Retention and mitigation of metals in sediment, soil, water, and plant of a newly constructed root-channel wetland (China) from slightly polluted source water.

PubMed

Wang, Baoling; Wang, Yu; Wang, Weidong

2014-01-01

Constructed root-channel wetland (CRCW) is a term for pre-pond/wetland/post-pond complexes, where the wetland includes plant-bed/ditch landscape and root-channel structure. Source water out of pre-ponds flows through alternate small ditches and plant beds with root-channels via a big ditch under hydraulic regulation. Then source water flows into post-ponds to finish final polishing. This article aims to explore the potential of components of a pilot CRCW in China on mitigating metals in micro-polluted source water during its initial operation stage. We investigated six heavy metals (Cd, Cr, Cu, Ni, Zn, and Pb) in surface sediment, plant-bed subsurface soil, water, and aquatic plants during 2012-2013. Monitoring results showed that pond/ditch sediments and plant-bed soil retained a significant amount of Cr, Ni, and Zn with 93.1%, 72.4%, and 57.5% samples showing contamination factor above limit 1 respectively. Remarkably the high values of metal enrichment factor (EF) occurred in root-channel zones. Water monitoring results indicated that Ni, Zn, and Pb were removed by 78.5% (66.7%), 57.6% (59.6%), and 26.0% (7.5%) in east (west) wetland respectively. Mass balance estimation revealed that heavy metal mass in the pond/ditch sediments accounted for 63.30% and that in plant-bed soil 36.67%, while plant uptake occupied only 0.03%. The heavy metal accretion flux in sediments was 0.41 - 211.08 μg · cm(-2) · a(-1), less than that in plant-bed soil (0.73 - 543.94 μg · cm(-2) · a(-1)). The 1.83 ha wetland has retained about 86.18 kg total heavy metals within 494 days after operation. This pilot case study proves that constructed root-channel wetland can reduce the potential ecological risk of purified raw water and provide a new and effective method for the removal of heavy metals from drinking water sources.

Use of reclaimed water for power plant cooling.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Veil, J. A.; Environmental Science Division

2007-10-16

Freshwater demands are steadily increasing throughout the United States. As its population increases, more water is needed for domestic use (drinking, cooking, cleaning, etc.) and to supply power and food. In arid parts of the country, existing freshwater supplies are not able to meet the increasing demands for water. New water users are often forced to look to alternative sources of water to meet their needs. Over the past few years, utilities in many locations, including parts of the country not traditionally water-poor (e.g., Georgia, Maryland, Massachusetts, New York, and North Carolina) have needed to reevaluate the availability of watermore » to meet their cooling needs. This trend will only become more extreme with time. Other trends are likely to increase pressure on freshwater supplies, too. For example, as populations increase, they will require more food. This in turn will likely increase demands for water by the agricultural sector. Another example is the recent increased interest in producing biofuels. Additional water will be required to grow more crops to serve as the raw materials for biofuels and to process the raw materials into biofuels. This report provides information about an opportunity to reuse an abundant water source -- treated municipal wastewater, also known as 'reclaimed water' -- for cooling and process water in electric generating facilities. The report was funded by the U.S. Department of Energy's (DOE's) National Energy Technology Laboratory (NETL) Innovations for Existing Plants research program (Feeley 2005). This program initiated an energy-water research effort in 2003 that includes the availability and use of 'nontraditional sources' of water for use at power plants. This report represents a unique reference for information on the use of reclaimed water for power plant cooling. In particular, the database of reclaimed water user facilities described in Chapter 2 is the first comprehensive national effort to identify and catalog those plants that are using reclaimed water for cooling.« less

The Incorporation and Initialization of Cloud Water/ice in AN Operational Forecast Model

NASA Astrophysics Data System (ADS)

Zhao, Qingyun

Quantitative precipitation forecasts have been one of the weakest aspects of numerical weather prediction models. Theoretical studies show that the errors in precipitation calculation can arise from three sources: errors in the large-scale forecasts of primary variables, errors in the crude treatment of condensation/evaporation and precipitation processes, and errors in the model initial conditions. A new precipitation parameterization scheme has been developed to investigate the forecast value of improved precipitation physics via the introduction of cloud water and cloud ice into a numerical prediction model. The main feature of this scheme is the explicit calculation of cloud water and cloud ice in both the convective and stratiform precipitation parameterization. This scheme has been applied to the eta model at the National Meteorological Center. Four extensive tests have been performed. The statistical results showed a significant improvement in the model precipitation forecasts. Diagnostic studies suggest that the inclusion of cloud ice is important in transferring water vapor to precipitation and in the enhancement of latent heat release; the latter subsequently affects the vertical motion field significantly. Since three-dimensional cloud data is absent from the analysis/assimilation system for most numerical models, a method has been proposed to incorporate observed precipitation and nephanalysis data into the data assimilation system to obtain the initial cloud field for the eta model. In this scheme, the initial moisture and vertical motion fields are also improved at the same time as cloud initialization. The physical initialization is performed in a dynamical initialization framework that uses the Newtonian dynamical relaxation method to nudge the model's wind and mass fields toward analyses during a 12-hour data assimilation period. Results from a case study showed that a realistic cloud field was produced by this method at the end of the data assimilation period. Precipitation forecasts have been significantly improved as a result of the improved initial cloud, moisture and vertical motion fields.

Mars H Escape is potentially dominated by a high-altitude water source

NASA Astrophysics Data System (ADS)

Chaffin, Michael; Deighan, Justin; Schneider, Nick; Stewart, Ian

2017-04-01

H escape from the Mars atmosphere has removed a large part of Mars' initial water inventory. Until recently, this escape was thought to be slow and steady, sourced from long-lived molecular hydrogen whose lightness and volatility in comparison with water allow it to penetrate the upper atmosphere. Contradicting this thinking, observations from the Hubble Space Telescope and Mars Express, as well as more recent MAVEN measurements, indicate that H escape varies by at least a factor of ten over the Mars year and is largest in Southern Summer near perihelion. At the largest rates, H escape exceeds the ability of molecular hydrogen to supply the escape fluxes observed. At the same time in Southern Summer, Mars Express solar occultations have shown unexpectedly large concentrations of water at high altitude, potentially providing a source of escaping H unaccounted for in standard models. Here we show via photochemical modeling that the presence of this high altitude water can partially explain the large escape rates observed in Southern Summer. We further show that this escaping H is not in immediate balance with O escape, and therefore that short-term atmospheric dynamics can drive long-term variations in the oxidation balance and volatile content of planetary atmospheres. Future simultaneous observations by MAVEN, Mars Express, and the Trace Gas Orbiter may provide a direct test of this mechanism.

SYNTHESIS AND MUTAGENICITY OF DIRECT DYES FROM 4,4'-DIAMINO-PARA-TERPHENYL AND 4,4'-DIAMINO-PARA-QUATERPHENYL

EPA Science Inventory

DBPs in drinking water can be controlled by the type of treatment and by knowing and controlling major sources of DBP toxicant precursors and toxicants that "evade" treatment processes. Efforts are being directed at one category at a time. The initial precursor categories to be c...

Halogenated 17ß-estradiol surrogates: synthesis, estrogenic activity, and initial investigations of fate in soil/water systems

USDA-ARS?s Scientific Manuscript database

17ß-Estradiol (E2) is a natural, endocrine-disrupting, steroid hormone excreted by all vertebrates that can enter the environment from domestic animal and wildlife wastes. Multiple field studies using food animal manures as E2 sources suggest significant background concentrations of E2 (e.g., wildli...

NO3 and OH initiated secondary aerosol formation from aliphatic amines - salt formation and effect of water vapor

USDA-ARS?s Scientific Manuscript database

Aliphatic amines enter the atmosphere from a variety of sources, and have been detected existing in gas and particle phases in the atmosphere. Similar to ammonia, amines can form inorganic salt through acid-base reactions. However, the atmospheric behavior of amines with atmospheric oxidants (e.g. n...

The National Audubon Society's eastern forest conservation initiative: examining opportunities for bird conservation at a regional scale

Treesearch

Curtis Smalling; Mary Elfner

2010-01-01

The forests of the east are under tremendous pressure from a variety of sources, including increasing development and fragmentation, declining air quality, declining water quality, and global climate change. Many priority bird species depend on these forested habitats, including a high percentage (75 percent) of neotropical migrant breeding species.

Water Treatment Using Advanced Ultraviolet Light Sources Final Report CRADA No. TC02089.0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoppes, W.; Oster, S.

This was a collaborative effort between Lawrence Livermore National Security, LLC as manager and operator of Lawrence Livermore National Laboratory (LLNL) and Teknichal Services, LLC (TkS), to develop water treatment systems using advanced ultraviolet light sources. The Russian institutes involved with this project were The High Current Electronics Institute (HCEI) and Russian Institute of Technical Physics-Institute of Experimental Physics (VNIIEF). HCEI and VNIIEF developed and demonstrated the potential commercial viability of short-wavelength ultraviolet excimer lamps under a Thrust 1 Initiatives for Proliferation Prevention (IPP) Program. The goals of this collaboration were to demonstrate both the commercial viability of excilampbased watermore » disinfection and achieve further substantial operational improvement in the lamps themselves; particularly in the area of energy efficiency.« less

A critical assessment of flux and source term closures in shallow water models with porosity for urban flood simulations

NASA Astrophysics Data System (ADS)

Guinot, Vincent

2017-11-01

The validity of flux and source term formulae used in shallow water models with porosity for urban flood simulations is assessed by solving the two-dimensional shallow water equations over computational domains representing periodic building layouts. The models under assessment are the Single Porosity (SP), the Integral Porosity (IP) and the Dual Integral Porosity (DIP) models. 9 different geometries are considered. 18 two-dimensional initial value problems and 6 two-dimensional boundary value problems are defined. This results in a set of 96 fine grid simulations. Analysing the simulation results leads to the following conclusions: (i) the DIP flux and source term models outperform those of the SP and IP models when the Riemann problem is aligned with the main street directions, (ii) all models give erroneous flux closures when is the Riemann problem is not aligned with one of the main street directions or when the main street directions are not orthogonal, (iii) the solution of the Riemann problem is self-similar in space-time when the street directions are orthogonal and the Riemann problem is aligned with one of them, (iv) a momentum balance confirms the existence of the transient momentum dissipation model presented in the DIP model, (v) none of the source term models presented so far in the literature allows all flow configurations to be accounted for(vi) future laboratory experiments aiming at the validation of flux and source term closures should focus on the high-resolution, two-dimensional monitoring of both water depth and flow velocity fields.

Characterizing large river sounds: Providing context for understanding the environmental effects of noise produced by hydrokinetic turbines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bevelhimer, Mark S.; Deng, Z. Daniel; Scherelis, Constantin

2016-01-01

Underwater noise associated with the installation and operation of hydrokinetic turbines in rivers and tidal zones presents a potential environmental concern for fish and marine mammals. Comparing the spectral quality of sounds emitted by hydrokinetic turbines to natural and other anthropogenic sound sources is an initial step at understanding potential environmental impacts. Underwater recordings were obtained from passing vessels of different sizes and other underwater sound sources in both static and flowing waters. Static water measurements were taken in a lake with minimal background noise. Flowing water measurements were taken at a previously proposed deployment site for hydrokinetic turbines onmore » the Mississippi River, where the sound of flowing water is included in background measurements. The size of vessels measured ranged from a small fishing boat with a 60 HP outboard motor to an 18-unit barge train being pushed upstream by tugboat. As expected, large vessels with large engines created the highest sound levels, and when compared to the sound created by an operating HK turbine were many times greater. A comparison of sound levels from the same sources at different distances using both spherical and cylindrical sound attenuation functions suggests that spherical model results more closely approximate observed values.« less

Drinking Water Supply, Sanitation, and Hygiene Promotion Interventions in Two Slum Communities in Central Uganda.

PubMed

Musoke, David; Ndejjo, Rawlance; Halage, Abdullah Ali; Kasasa, Simon; Ssempebwa, John C; Carpenter, David O

2018-01-01

Poor water, sanitation, and hygiene (WASH) continue to contribute to the high prevalence of diarrhoeal diseases in low-income countries such as Uganda particularly in slums. We implemented a 3-year WASH project in two urban slums in Uganda with a focus on safe drinking water and improvement in sanitation. The project implemented community and school interventions in addition to capacity building initiatives. Community interventions included home improvement campaigns, clean-up exercises, water quality assessment, promotion of drinking safe water through household point-of-use chlorination, promotion of hand washing, and support towards solid waste management. In schools, the project supported health clubs and provided them with "talking compound" messages. The capacity building initiatives undertaken included training of youth and community health workers. Project evaluation revealed several improvements in WASH status of the slums including increase in piped water usage from 38% to 86%, reduction in use of unprotected water sources from 30% to 2%, reduction in indiscriminate disposal of solid waste from 18% to 2%, and increase in satisfaction with solid waste management services from 40% to 92%. Such proactive and sustainable community interventions have the potential to not only improve lives of slum inhabitants in developing countries but also create lasting impact.

Drinking Water Supply, Sanitation, and Hygiene Promotion Interventions in Two Slum Communities in Central Uganda

PubMed Central

Halage, Abdullah Ali; Kasasa, Simon; Ssempebwa, John C.; Carpenter, David O.

2018-01-01

Poor water, sanitation, and hygiene (WASH) continue to contribute to the high prevalence of diarrhoeal diseases in low-income countries such as Uganda particularly in slums. We implemented a 3-year WASH project in two urban slums in Uganda with a focus on safe drinking water and improvement in sanitation. The project implemented community and school interventions in addition to capacity building initiatives. Community interventions included home improvement campaigns, clean-up exercises, water quality assessment, promotion of drinking safe water through household point-of-use chlorination, promotion of hand washing, and support towards solid waste management. In schools, the project supported health clubs and provided them with “talking compound” messages. The capacity building initiatives undertaken included training of youth and community health workers. Project evaluation revealed several improvements in WASH status of the slums including increase in piped water usage from 38% to 86%, reduction in use of unprotected water sources from 30% to 2%, reduction in indiscriminate disposal of solid waste from 18% to 2%, and increase in satisfaction with solid waste management services from 40% to 92%. Such proactive and sustainable community interventions have the potential to not only improve lives of slum inhabitants in developing countries but also create lasting impact. PMID:29623096

Effects of feeder design and changing source of water to a location separate from the wet-dry feeder at 4 or 8 weeks before harvest on growth, feeding behavior, and carcass characteristics of finishing pigs.

PubMed

Bergstrom, J R; Nelssen, J L; Edwards, L N; Tokach, M D; Dritz, S S; Goodband, R D; DeRouchey, J M

2012-12-01

Our objectives were to compare a conventional dry (5-space, 152.4-cm-wide) and a wet-dry (double-sided, each side = 38.1-cm-wide single space) feeder and to determine if changing the source of water to a location separate from a wet-dry feeder would result in improved G:F and carcass characteristics. Water supply to the wet-dry feeder was shut off and the cup waterer was turned on in 8 pens at 8 (d 69) or 4 (d 97) wk prior to harvest. For the remaining 8 wet-dry feeder pens, the feeder provided the sole water source for the entire experiment. A total of 1,296 pigs (PIC, 337 × 1050; initially 19.4 kg BW) were used, with 27 pigs/pen (14 barrows and 13 gilts) and 24 pens/feeder design. From d 0 to 69, pigs fed with the wet-dry feeder had increased (P < 0.05) ADG, ADFI, G:F, and d 69 BW compared with those using the conventional dry feeder. Overall (d 0 to 124), pigs using fed with the water source in the wet-dry feeder the entire time had greater (P < 0.05) ADG, ADFI, final BW, and HCW the other treatments. The overall G:F was not different (P > 0.05) among pigs fed with the different feeder treatments. Pigs fed with the wet-dry feeder where water source was changed at 4 wk before harvest had greater (P < 0.05) ADG than pigs that used a conventional dry feeder. Pigs where the water source was changed at 4 wk had greater (P < 0.05) ADFI than those were the water source was changed 8 wk prior to harvest, and for pigs fed with the conventional dry feeder ADFI was intermediate. Back fat depth of pigs where the water source was changed at 8 wk before harvest was reduced (P < 0.05) compared with all other treatments and LM depth was greater (P < 0.05) than that of pigs using a conventional dry feeder and where the water source was changed at 4 week before harvest. Pigs fed using the wet-dry feeder visited the feeder less frequently (P < 0.05) and spent less total time at the feeder (P < 0.05) than those fed with the conventional dry feeder. The differences in feeding patterns remained even after the access to water was removed from the wet-dry feeder, with no change in the amount of aggressive behavior observed at the feeder. Pigs fed with a wet-dry feeder had an increased growth rate compared with those fed with a conventional dry feeder. Although measures of carcass leanness were improved by changing the location of the water, removing the water from the feeder also eliminated any net improvement in BW from using a wet-dry feeder.

Characterization of Water Quality Changes During Storm Events: New Methods to Protect Drinking Water Supplies

NASA Astrophysics Data System (ADS)

Sturdevant-Rees, P. L.; Long, S. C.; Barten, P. K.

2002-05-01

A forty-month investigation to collect microbial and water-quality measurements during storm events under a variety of meteorological and land-use conditions is in its initial stages. Intense sampling during storm event periods will be used to optimize sampling and analysis strategies for accurate determination of constituent loads. Of particular interest is identification of meteorological and hydrologic conditions under which sampling and analysis of surface waters for traditional microbial organisms, emerging microbial organisms and non-bacterial pathogens are critical to ensure the integrity of surface-water drinking supplies. This work is particular to the Quabbin-Ware-Wachusett reservoir system in Massachusetts, which provides unfiltered drinking water to 2.5 million people in Boston and surrounding communities. Sampling and analysis strategies will be optimized in terms of number of samples over the hydrograph, timing of sample collection (including sample initiation), constituents measured, volumes analyzed, and monetary and personnel costs. Initial water-quality analyses include pH, temperature, turbidity, conductivity, total suspended solids, total phosphorus, total Kjeldahl-nitrogen, ammonia nitrogen, and total and fecal coliforms. Giardia cysts and Cryptosporidium oocysts will also be measured at all sample sites. Sorbitol-fermenting Bifidobacteria, Rhodococcus coprophilus, Clostridium perfringens spores, and Somatic and F-specific coliphages are measured at select sites as potential alternative source-specific indicator organisms. It is anticipated that the final database will consist of transport data for the above parameters during twenty-four distinct storm-events in addition to monthly baseline data. Results and analyses for the first monitored storm-event will be presented.

Chlorine-36 and the initial value problem

USGS Publications Warehouse

Davis, S.N.; Cecil, D.; Zreda, M.; Sharma, Prakash

1998-01-01

Chlorine-36 is a radionuclide with a half-life of 3.01 ?? 105a. Most 36Cl in the hydrosphere originates from cosmic radiation interacting with atmospheric gases. Large amounts were also produced by testing thermonuclear devices during 1952-58. Because the monovalent anion, chloride, is the most common form of chlorine found in the hydrosphere and because it is extremely mobile in aqueous systems, analyses of both total Cl- as well as 36Cl have been important in numerous hydrologic studies. In almost all applications of 36Cl, a knowledge of the initial, or pre-anthropogenic, levels of 36CL is useful, as well as essential in some cases. Standard approaches to the determination of initial values have been to: (a) calculate the theoretical cosmogenic production and fallout, which varies according to latitude; (b) measure 36CL in present-day precipitation and assume that anthropogenic components can be neglected; (c) assume that shallow ground-water retains a record of the initial concentration; (d) extract 36CL from vertical depth profiles in desert soils; (e) recover 36CL from cores of glacial ice; and (f) calculate subsurface production of 36CL for water that has been isolated from the atmosphere for more than one million years. The initial value from soil profiles and ice cores is taken as the value that occurs directly below the depth of the easily defined bomb peak. All six methods have serious weaknesses. Complicating factors include 36CL concentrations not related to cosmogenic sources, changes in cosmogenic production with time, mixed sources of chloride in groundwater, melting and refrrezing of waterin glaciers, and seasonal groungwater recharge that does not contain average year-long concentrations of 36Cl.

Assessing Potential Additional PFAS Retention Processes in the Subsurface

NASA Astrophysics Data System (ADS)

Brusseau, M. L.

2017-12-01

Understanding the transport and fate of per- and poly-fluorinated alkyl substances (PFASs) in the subsurface is critical for accurate risk assessments and design of effective remedial actions. Current conceptual and mathematical models are based on an assumption that solid-phase adsorption is the sole source of retention for PFASs. However, additional retention processes may be relevant for PFAS compounds in vadose-zone systems and in source zones that contain trapped immiscible organic liquids. These include adsorption at the air-water interface, partitioning to the soil atmosphere, adsorption at the NAPL-water interface, and absorption by NAPL. A multi-process retention model is proposed to account for these potential additional sources of PFAS retardation. An initial assessment of the relative magnitudes and significance of these retention processes was conducted for three representative PFASs, perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), and 8:2 fluorotelomer alcohol (FTOH). Data collected from the literature were used to determine measured or estimated values for the relevant distribution coefficients, which were in turn used to calculate retardation factors for a representative porous medium. Adsorption at the air-water interface was shown to be a primary source of retention for PFOA and PFOS, contributing approximately 80% of total retardation. Adsorption to NAPL-water interfaces and absorption by bulk NAPL were also shown to be significant sources of retention for PFOS and PFOA. The latter process was the predominant source of retention for 8:2 FTOH, contributing 98% of total retardation. These results indicate that we may anticipate significant retention of PFASs by these additional processes. In such cases, retardation of PFASs in source areas may be significantly greater than what is typically estimated based on the standard assumption of solid-phase adsorption as the sole retention mechanism. This has significant ramifications for accurate determination of the migration potential and magnitude of mass flux to groundwater, as well as for calculations of contaminant mass residing in source zones.

Community-acquired Legionnaires' disease in a renal transplant recipient with unclear incubation period: the importance of molecular typing.

PubMed

Cassier, P; Bénet, T; Nicolle, M C; Brunet, M; Buron, F; Morelon, E; Béraud, L; Descours, G; Jarraud, S; Vanhems, P

2015-10-01

Transplant recipients are at risk of developing Legionnaires' disease (LD) because of impaired cellular immunity. Here, we describe a renal transplant recipient who developed LD at least 10 days after hospital admission and transplantation. The hospital water network was initially suspected, but further testing determined that the probable source was the patient's domestic water supply. Our report also suggests that the patient's immunosuppressed state may have switched potential colonization to pneumonia. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

In Situ Characterization of the Initial Effect of Water on Molecular Interactions at the Interface of Organic/Inorganic Hybrid Systems

PubMed Central

Pletincx, Sven; Trotochaud, Lena; Fockaert, Laura-Lynn; Mol, Johannes M. C.; Head, Ashley R.; Karslıoğlu, Osman; Bluhm, Hendrik; Terryn, Herman; Hauffman, Tom

2017-01-01

Probing initial interactions at the interface of hybrid systems under humid conditions has the potential to reveal the local chemical environment at solid/solid interfaces under real-world, technologically relevant conditions. Here, we show that ambient pressure X-ray photoelectron spectroscopy (APXPS) with a conventional X-ray source can be used to study the effects of water exposure on the interaction of a nanometer-thin polyacrylic acid (PAA) layer with a native aluminum oxide surface. The formation of a carboxylate ionic bond at the interface is characterized both with APXPS and in situ attenuated total reflectance Fourier transform infrared spectroscopy in the Kretschmann geometry (ATR-FTIR Kretschmann). When water is dosed in the APXPS chamber up to 5 Torr (~28% relative humidity), an increase in the amount of ionic bonds at the interface is observed. To confirm our APXPS interpretation, complementary ATR-FTIR Kretschmann experiments on a similar model system, which is exposed to an aqueous electrolyte, are conducted. These spectra demonstrate that water leads to an increased wet adhesion through increased ionic bond formation. PMID:28327587

Does External Funding Help Adaptation? Evidence from Community-Based Water Management in the Colombian Andes

NASA Astrophysics Data System (ADS)

Murtinho, Felipe; Eakin, Hallie; López-Carr, David; Hayes, Tanya M.

2013-11-01

Despite debate regarding whether, and in what form, communities need external support for adaptation to environmental change, few studies have examined how external funding impacts adaptation decisions in rural resource-dependent communities. In this article, we use quantitative and qualitative methods to assess how different funding sources influence the initiative to adapt to water scarcity in the Colombian Andes. We compare efforts to adapt to water scarcity in 111 rural Andean communities with varied dependence on external funding for water management activities. Findings suggest that despite efforts to use their own internal resources, communities often need external support to finance adaptation strategies. However, not all external financial support positively impacts a community’s abilities to adapt. Results show the importance of community-driven requests for external support. In cases where external support was unsolicited, the results show a decline, or “crowding-out,” in community efforts to adapt. In contrast, in cases where communities initiated the request for external support to fund their own projects, findings show that external intervention is more likely to enhance or “crowds-in” community-driven adaptation.

Leachability of heavy metals from growth media containing source-separated municipal solid waste compost

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sawhney, B.L.; Bugbee, G.J.; Stilwell, D.E.

1994-07-01

The leaching of heavy metals in source-separated municipal solid waste (MSW) compost was determined by irrigation leaching of growth medium, admixed with varying amounts of compost, used for container grown plants. Perennial flowers (black-eyed Susan, Rudbeckia hirta L.) were grown in 2-L containers filled with the growth medium for a 10-wk period. Rainfall was supplemented with overhead irrigation to supply 2 cm of water per day. Leachates collected over each 2-wk period were analyzed for Cd, Cr, Cu, Ni, Pb, and Zn using atomic spectrometry. Concentrations of the heavy metals in the leachates increased with increasing proportions of MSW compostmore » in the growth medium, but decreased with time of leaching. Leaching of the metals occurred at relatively high concentrations initially, followed by continued leaching at low concentrations. The initial leaching of heavy metals is attributed to their soluble or exchangeable forms and the subsequent slow leaching to the solid compounds. The concentrations of the heavy metals remained below the current drinking water standards in all treatments throughout the leaching period. The results thus suggest that contamination of groundwater with heavy metals from source-separated MSW compost applied as a soil amendment should be negligible, as the low concentrations in the leachates leaving the surface soil would be further attenuated by the subsoil. 29 refs., 6 figs., 1 tab.« less

Community Knowledge about Water: Who Has Better Knowledge and Is This Associated with Water-Related Behaviors and Support for Water-Related Policies?

PubMed Central

Fielding, Kelly S.; Newton, Fiona J.

2016-01-01

Sustainable approaches to water management require broad community acceptance of changes in policy, practice and technology, which in turn, requires an engaged community. A critical first step in building an engaged community is to identify community knowledge about water management, an issue rarely examined in research. To address this, we surveyed a representative sample of Australian adults (n = 5172). Knowledge was assessed using 15 questions about impact of household activities on waterways, the urban water cycle, and water management. This survey also examined demographics, psychosocial characteristics, exposure to water-related information, and water-related behaviors and policy support. Participants correctly answered a mean of 8.0 questions (Range 0–15). Most respondents knew that household actions can reduce water use and influence waterway health, whereas less than one third correctly identified that domestic wastewater is treated prior to entering waterways, urban stormwater is not treated, and that these are carried via different pipes. Higher water knowledge was associated with older age, higher education and living in non-urban areas. Poorer water knowledge was associated with speaking a language other than English in the home. Garden size, experience of water restrictions, satisfaction, waterway use for swimming, and certain information sources were also associated with knowledge. Greater water knowledge was associated with adoption of water-saving and pollution-reduction behaviors, and support for both alternative water sources and raingardens. These findings confirm the importance of community knowledge, and identify potential subgroups who may require additional targeting to build knowledge and support for water management initiatives. PMID:27428372

Community Knowledge about Water: Who Has Better Knowledge and Is This Associated with Water-Related Behaviors and Support for Water-Related Policies?

PubMed

Dean, Angela J; Fielding, Kelly S; Newton, Fiona J

2016-01-01

Sustainable approaches to water management require broad community acceptance of changes in policy, practice and technology, which in turn, requires an engaged community. A critical first step in building an engaged community is to identify community knowledge about water management, an issue rarely examined in research. To address this, we surveyed a representative sample of Australian adults (n = 5172). Knowledge was assessed using 15 questions about impact of household activities on waterways, the urban water cycle, and water management. This survey also examined demographics, psychosocial characteristics, exposure to water-related information, and water-related behaviors and policy support. Participants correctly answered a mean of 8.0 questions (Range 0-15). Most respondents knew that household actions can reduce water use and influence waterway health, whereas less than one third correctly identified that domestic wastewater is treated prior to entering waterways, urban stormwater is not treated, and that these are carried via different pipes. Higher water knowledge was associated with older age, higher education and living in non-urban areas. Poorer water knowledge was associated with speaking a language other than English in the home. Garden size, experience of water restrictions, satisfaction, waterway use for swimming, and certain information sources were also associated with knowledge. Greater water knowledge was associated with adoption of water-saving and pollution-reduction behaviors, and support for both alternative water sources and raingardens. These findings confirm the importance of community knowledge, and identify potential subgroups who may require additional targeting to build knowledge and support for water management initiatives.

Chemometric evaluation of nitrate contamination in the groundwater of a hard rock area in Dharapuram, south India

NASA Astrophysics Data System (ADS)

Sajil Kumar, P. J.; Jegathambal, P.; James, E. J.

2014-12-01

This paper presents the results of investigations on groundwater nitrate contamination in the Dharapuram area of Tamil Nadu in south India as a primary step to initiate denitrification. Groundwater samples were collected from 26 selected locations during the pre-monsoon season in July 2010 and analysed for nitrate and other water quality parameters. Two important water types were identified, viz. Ca-Na-HCO3 and mixed Ca-Mg-Cl. It is found that the majority of samples possess high nitrate concentration; 57 % of samples exceeded the permissible limit of Indian (45 mg/L) and WHO (50 mg/L) drinking water standard. Spatial distribution map of NO3 suggested that major contamination was observed in the SW and NW parts of the study area. This result was in agreement with the corresponding land-use pattern in this study area. Denitrification process at greater depths was evident from the negative correlation between NO3 and well depth. The sources and controlling factors of high nitrate were investigated using cross plots of NO3 with other selected hydrochemical parameters. Positive correlation for NO3 was observed with EC, K, Cl and SO4. This analysis was capable of differentiating the various sources of nitrate in groundwater. The major sources of nitrate contamination are identified as areas of high fertilizer application, sewages and animal waste dumping yards. Regulation of these pollutant sources with appropriate and cost-effective denitrification process can restore the water quality in this area.

Effluent trading in river systems through stochastic decision-making process: a case study.

PubMed

Zolfagharipoor, Mohammad Amin; Ahmadi, Azadeh

2017-09-01

The objective of this paper is to provide an efficient framework for effluent trading in river systems. The proposed framework consists of two pessimistic and optimistic decision-making models to increase the executability of river water quality trading programs. The models used for this purpose are (1) stochastic fallback bargaining (SFB) to reach an agreement among wastewater dischargers and (2) stochastic multi-criteria decision-making (SMCDM) to determine the optimal treatment strategy. The Monte-Carlo simulation method is used to incorporate the uncertainty into analysis. This uncertainty arises from stochastic nature and the errors in the calculation of wastewater treatment costs. The results of river water quality simulation model are used as the inputs of models. The proposed models are used in a case study on the Zarjoub River in northern Iran to determine the best solution for the pollution load allocation. The best treatment alternatives selected by each model are imported, as the initial pollution discharge permits, into an optimization model developed for trading of pollution discharge permits among pollutant sources. The results show that the SFB-based water pollution trading approach reduces the costs by US$ 14,834 while providing a relative consensus among pollutant sources. Meanwhile, the SMCDM-based water pollution trading approach reduces the costs by US$ 218,852, but it is less acceptable by pollutant sources. Therefore, it appears that giving due attention to stability, or in other words acceptability of pollution trading programs for all pollutant sources, is an essential element of their success.

Predicting nonpoint stormwater runoff quality from land use

PubMed Central

2018-01-01

Evaluating the impact of urban development on natural ecosystem processes has become an increasingly complex task for planners, environmental scientists, and engineers. As the built environment continues to grow, unregulated nonpoint pollutants from increased human activity and large-scale development severely stress urban streams and lakes resulting in their currently impaired or degraded state. In response, integrated water quality management programs have been adopted to address these unregulated nonpoint pollutants by utilizing best management practices (BMPs) that treat runoff as close to the source as possible. Knowing where to install effective BMPs is no trivial task, considering budget constraints and the spatially extensive nature of nonpoint stormwater runoff. Accordingly, this paper presents an initial, straightforward and cost-effective methodology to identify critical nonpoint pollutant source watersheds through correlation of water quality with land use. Through an illustrative application to metropolitan Denver, Colorado, it is shown how this method can be used to aid stormwater professionals to evaluate and specify retrofit locations in need of water quality treatment features reduce, capture and treat stormwater runoff prior to entering receiving waters. PMID:29742172

Predicting nonpoint stormwater runoff quality from land use.

PubMed

Zivkovich, Brik R; Mays, David C

2018-01-01

Evaluating the impact of urban development on natural ecosystem processes has become an increasingly complex task for planners, environmental scientists, and engineers. As the built environment continues to grow, unregulated nonpoint pollutants from increased human activity and large-scale development severely stress urban streams and lakes resulting in their currently impaired or degraded state. In response, integrated water quality management programs have been adopted to address these unregulated nonpoint pollutants by utilizing best management practices (BMPs) that treat runoff as close to the source as possible. Knowing where to install effective BMPs is no trivial task, considering budget constraints and the spatially extensive nature of nonpoint stormwater runoff. Accordingly, this paper presents an initial, straightforward and cost-effective methodology to identify critical nonpoint pollutant source watersheds through correlation of water quality with land use. Through an illustrative application to metropolitan Denver, Colorado, it is shown how this method can be used to aid stormwater professionals to evaluate and specify retrofit locations in need of water quality treatment features reduce, capture and treat stormwater runoff prior to entering receiving waters.

Impact of UV–H2O2 Advanced Oxidation and Aging Processes on GAC Capacity for the Removal of Cyanobacterial Taste and Odor Compounds

PubMed Central

Zamyadi, Arash; Sawade, Emma; Ho, Lionel; Newcombe, Gayle; Hofmann, Ron

2015-01-01

Cyanobacteria and their taste and odor (T&O) compounds are a growing concern in water sources globally. Geosmin and 2-methylisoborneol (MIB) are the most commonly detected T&O compounds associated with cyanobacterial presence in drinking water sources. The use of ultraviolet and hydrogen peroxide (H2O2) as an advanced oxidation treatment for T&O control is an emerging technology. However, residual H2O2 (>80% of the initial dose) has to be removed from water prior final disinfection. Recently, granular activated carbon (GAC) is used to remove H2O2 residual. The objective of this study is to assess the impact of H2O2 quenching and aging processes on GAC capacity for the removal of geosmin and MIB. Pilot columns with different types of GAC and presence/absence of H2O2 have been used for this study. H2O2 removal for the operational period of 6 months has no significant impact on GAC capacity to remove the geosmin and MIB from water. PMID:26462247

Impact of UV-H2O2 Advanced Oxidation and Aging Processes on GAC Capacity for the Removal of Cyanobacterial Taste and Odor Compounds.

PubMed

Zamyadi, Arash; Sawade, Emma; Ho, Lionel; Newcombe, Gayle; Hofmann, Ron

2015-01-01

Cyanobacteria and their taste and odor (T&O) compounds are a growing concern in water sources globally. Geosmin and 2-methylisoborneol (MIB) are the most commonly detected T&O compounds associated with cyanobacterial presence in drinking water sources. The use of ultraviolet and hydrogen peroxide (H2O2) as an advanced oxidation treatment for T&O control is an emerging technology. However, residual H2O2 (>80% of the initial dose) has to be removed from water prior final disinfection. Recently, granular activated carbon (GAC) is used to remove H2O2 residual. The objective of this study is to assess the impact of H2O2 quenching and aging processes on GAC capacity for the removal of geosmin and MIB. Pilot columns with different types of GAC and presence/absence of H2O2 have been used for this study. H2O2 removal for the operational period of 6 months has no significant impact on GAC capacity to remove the geosmin and MIB from water.

Using Natural Geochemical Tracers to Discern the Dominant Sources of Freshwater into Biscayne Bay, Southeast Florida

NASA Astrophysics Data System (ADS)

Stalker, J. C.; Price, R. M.; Swart, P. K.

2005-05-01

Biscayne Bay is a sub-tropical estuary located on the carbonate platform of south Florida. The water occupying Biscayne Bay is a balance of saltwater influx from the open ocean and freshwater inputs from precipitation, surface water runoff, and submarine groundwater discharge. The bays watershed includes a total of 3 million inhabitants, the major urban centers of Miami and Ft. Lauderdale, as well as the Everglades system. With the development of south Florida, the natural diffuse groundwater and stream flow into the bay has been replaced by a large system of canals and levees in an effort to control flooding and drain swampland. The Comprehensive Everglades Restoration Plan includes changes in the freshwater deliveries to Biscayne Bay from point-source discharges via canals to non-point source discharges via wetlands and groundwater flow. The balance of salinity in Biscayne Bay effects sensitive seagrass and tidal ecosystems including numerous species of corals and other biota. A comprehensive understanding of the flow of freshwater into the bay is crucial to future planned developments and restorations. The goal of this study is to use naturally occurring geochemical constituents as tracers to identify and quantify the sources of freshwater, i.e. rainfall, canal flow, and groundwater, discharge to Biscayne Bay. In this study, discrete samples of precipitation, canal water, terrestrial groundwater, marine groundwater, and bay surface water are collected monthly and analyzed for the stable isotopes of hydrogen and oxygen as well as for major cations and anions. Initial results indicate that fresh groundwater has an isotopic signature (del 18O = -2.66 per mil, del D, -7.60 per mil) similar to rainfall (del 18O = -2.86 per mil, del D =-4.78 per mil). In contrast canal water has a heavy isotopic signature (del 18O = -0.46 per mil, del D = -2.48 per mil) due to evaporation. Thus it is possible to use stable isotopes of oxygen and hydrogen to separate canal water from precipitation and groundwater as a source of freshwater into the bay. Other geochemical constituents, such as calcium and magnesium are being investigated to further discern between the sources of canal water, rainfall and fresh groundwater. Both the stable isotopes and ion values will be placed in a mixing model to quantify and discern the dominant sources of freshwater into the Bay in both time and space.

High-Resolution Acoustic Imaging in the Agadir-Canyon Region, NW-Africa: Morphology, Processes and Geohazards

NASA Astrophysics Data System (ADS)

Krastel, S.; Wynn, R. B.; Feldens, P.; Unverricht, D.; Huehnerbach, V.; Stevenson, C.; Glogowski, S.; Schuerer, A.

2014-12-01

Agadir Canyon is one of the largest submarine canyons in the World, supplying giant submarine sediment gravity flows to the Agadir Basin and the wider Moroccan Turbidite System. While the Moroccan Turbidite System is extremely well investigated, almost no data from the source region, i.e. the Agadir Canyon, are available. Understanding why some submarine landslides remain as coherent blocks of sediment throughout their passage downslope, while others mix and disintegrate almost immediately after initial failure, is a major scientific challenge, which was addressed in the Agadir Canyon source region during Cruise MSM32. We collected ~ 1500 km of high-resolution seismic 2D-lines in combination with a dense net of hydroacoustic data. About 1000 km2 of sea floor were imaged during three deployments of TOBI (deep-towed sidescan sonar operated by the National Oceanography Centre Southampton). A total of 186 m of gravity cores and several giant box cores were recovered at more than 50 stations. The new data show that Agadir canyon is the source area of the world's largest submarine sediment flow, which occurred about 60,000 years ago. Up to 160 km3 of sediment was transported to the deep ocean in a single catastrophic event. For the first time, sediment flows of this scale have been tracked along their entire flow pathway. A major landslide area was identified south of Agadir Canyon. Landslide material enters Agadir canyon in about 2500 m water depth; the material is transported as debrite for at least another 200 km down the canyon. Initial data suggest that the last major slide from this source entered Agadir canyon at least 130,000 years ago. A large field of living deep-water corals was imaged north of Agadir canyon. To our knowledge, these are the first living cold water corals recovered off the coast of Morocco (except for the Gulf of Cadiz). They represent an important link between the known cold-water coral provinces off Mauritania and in the Gulf of Cádiz.

Investigation of severe water problem in urban areas of a developing country: the case of Dhaka, Bangladesh.

PubMed

Nahar, Mst Shamsun; Zhang, Jing; Ueda, Akira; Yoshihisa, Fujishiro

2014-12-01

The present study evaluated water supply geochemistry in Dhaka City, Bangladesh, to provide detailed trace level (subppb) water quality data that include major ions, low dissolved oxygen (DO) and toxic trace metals for sustainable development. Dhaka Groundwater, which almost uniformly meets the World Health Organization guideline, has become the preferred source. Due to groundwater depletion and an ever-increasing need to meet water demands by city residents, Dhaka water supply and sewerage authority has initiated the treatment of river water, despite the fact that very little is known about the geochemical structure, and trace metal content in the Dhaka water supply. Major ion composition of water samples was determined, and the results used to generate Stiff diagrams. The diagrams served to visually compare water from different sources based on units of mass/volume. Hydrochemical facies analysis showed supply ground and surface waters are comprised predominately of Ca-Na-Mg-HCO3 and Ca-Na-Mg-HCO3-Cl types. Spatial distribution of ions, and Na/Cl and Na/SiO2 molar ratio indicated that silicate weathering is the dominant geochemical process. Chemical data revealed that toxic Cr metal mobilization is associated with chemical hazards from the leather industry. The vulnerability of deep wells to contamination by As is governed by the geometry of induced groundwater flow paths and the geochemical conditions encountered between the shallow and deep regions of the aquifer. Quantifying total arsenic (As) and As from interlocking geochemical cycles (Fe, Mn) may assist in interpreting As dynamics in Dhaka well water. The surface source water was hypoxic to anoxic low DO associated with very high concentrations of biological oxygen demands, and electrical conductivity compared to industrial and non-industrial urban processes and standard activity guidelines. The results of this study should be applied to future research focused on the potential to improve water quality in urban and surrounding areas.

Importance of water source in controlling leaf leaching losses in a dwarf red mangrove ( Rhizophora mangle L.) wetland

NASA Astrophysics Data System (ADS)

Davis, Stephen E., III; Childers, Daniel L.

2007-01-01

The southern Everglades mangrove ecotone is characterized by extensive dwarf Rhizophora mangle L. shrub forests with a seasonally variable water source (Everglades - NE Florida Bay) and residence times ranging from short to long. We conducted a leaf leaching experiment to understand the influence that water source and its corresponding water quality have on (1) the early decay of R. mangle leaves and (2) the early exchange of total organic carbon (TOC) and total phosphorus (TP) between leaves and the water column. Newly senesced leaves collected from lower Taylor River (FL) were incubated in bottles containing water from one of three sources (Everglades, ambient mangrove, and Florida Bay) that spanned a range of salinity from 0 to 32‰, [TOC] from 710 to 1400 μM, and [TP] from 0.17 to 0.33 μM. We poisoned half the bottles in order to quantify abiotic processes (i.e., leaching) and assumed that non-poisoned bottles represented both biotic (i.e., microbial) and abiotic processes. We sacrificed bottles after 1,2, 5, 10, and 21 days of incubation and quantified changes in leaf mass and changes in water column [TOC] and [TP]. We saw 10-20% loss of leaf mass after 24 h—independent of water treatment—that leveled off by Day 21. After 3 weeks, non-poisoned leaves lost more mass than poisoned leaves, and there was only an effect of salinity on mass loss in poisoned incubations—with greatest leaching-associated losses in Everglades freshwater. Normalized concentrations of TOC in the water column increased by more than two orders of magnitude after 21 days with no effect of salinity and no difference between poisoned and non-poisoned treatments. However, normalized [TP] was lower in non-poisoned incubations as a result of immobilization by epiphytic microbes. This immobilization was greatest in Everglades freshwater and reflects the high P demand in this ecosystem. Immobilization of leached P in mangrove water and Florida Bay water was delayed by several days and may indicate an initial microbial limitation by labile C during the dry season.

Development of a compact laser-produced plasma soft X-ray source for radiobiology experiments

NASA Astrophysics Data System (ADS)

Adjei, Daniel; Ayele, Mesfin Getachew; Wachulak, Przemyslaw; Bartnik, Andrzej; Wegrzynski, Łukasz; Fiedorowicz, Henryk; Vyšín, Luděk; Wiechec, Anna; Lekki, Janusz; Kwiatek, Wojciech M.; Pina, Ladislav; Davídková, Marie; Juha, Libor

2015-12-01

A desk-top laser-produced plasma (LPP) source of soft X-rays (SXR) has been developed for radiobiology research. The source is based on a double-stream gas puff target, irradiated with the focused beam of a commercial Nd:YAG laser. The source has been optimized to get a maximum photon emission from LPP in the X-ray "water window" spectral wavelength range from 2.3 nm (i.e., an absorption edge of oxygen) to 4.4 nm (i.e., an absorption edge of carbon) (280-540 eV in photon energy units) by using argon gas-puff target and spectral filtering by free-standing thin foils. The present source delivers nanosecond pulses of soft X-rays at a fluence of about 4.2 × 103 photons/μm2/pulse on a sample placed inside the vacuum chamber. In this paper, the source design, radiation output characterization measurements and initial irradiation experiments are described. The source can be useful in addressing observations related to biomolecular, cellular and organisms' sensitivity to pulsed radiation in the "water window", where carbon atoms absorb X-rays more strongly than the oxygen, mostly present in water. The combination of the SXR source and the radiobiology irradiation layout, reported in this article, make possible a systematic investigation of relationships between direct and indirect action of ionizing radiation, an increase of a local dose in carbon-rich compartments of the cell (e.g., lipid membranes), an experimental estimation of a particular role of the Auger effect (in particular in carbon atoms) in the damage to biological systems, and the study of ionization/excitation-density (LET - Linear Energy Transfer) and dose-rate effects in radiobiology.

An Approach to Industrial Stormwater Benchmarks: Establishing and Using Site-Specific Threshold Criteria at Lawrence Livermore National Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Campbell, C G; Mathews, S

2006-09-07

Current regulatory schemes use generic or industrial sector specific benchmarks to evaluate the quality of industrial stormwater discharges. While benchmarks can be a useful tool for facility stormwater managers in evaluating the quality stormwater runoff, benchmarks typically do not take into account site-specific conditions, such as: soil chemistry, atmospheric deposition, seasonal changes in water source, and upstream land use. Failing to account for these factors may lead to unnecessary costs to trace a source of natural variation, or potentially missing a significant local water quality problem. Site-specific water quality thresholds, established upon the statistical evaluation of historic data take intomore » account these factors, are a better tool for the direct evaluation of runoff quality, and a more cost-effective trigger to investigate anomalous results. Lawrence Livermore National Laboratory (LLNL), a federal facility, established stormwater monitoring programs to comply with the requirements of the industrial stormwater permit and Department of Energy orders, which require the evaluation of the impact of effluent discharges on the environment. LLNL recognized the need to create a tool to evaluate and manage stormwater quality that would allow analysts to identify trends in stormwater quality and recognize anomalous results so that trace-back and corrective actions could be initiated. LLNL created the site-specific water quality threshold tool to better understand the nature of the stormwater influent and effluent, to establish a technical basis for determining when facility operations might be impacting the quality of stormwater discharges, and to provide ''action levels'' to initiate follow-up to analytical results. The threshold criteria were based on a statistical analysis of the historic stormwater monitoring data and a review of relevant water quality objectives.« less

Experimental Study of the Conditions for Quenching Forest Combustible Materials

NASA Astrophysics Data System (ADS)

Antonov, D. V.; Volkov, R. S.; Zhdanova, A. O.; Kuznetsov, G. V.; Strizhak, P. A.

2017-05-01

To confirm the possibility of quenching forest combustible materials by small volumes of water, experimental studies have been made of the processes of interaction of droplets, films, and aerosol flows of water with small sources of combustion of typical forest combustible materials — birch leaves, pine needles, birch and asp twigs. Model combustion sources in the form of cylinders of diameter 20-60 mm and height 40-100 mm were constructed. With the use of high-speed video recording, the characteristic times of thermal decomposition of forest combustibles and the times of suppressing combustion of these materials under various conditions of their interaction with water (pulsed supply of aerosol, injection of water ″mist″ with droplets of radius up to 100 μm, sequential supply of large drops of radius about 1.5 mm) have been determined. Volumes of water sufficient for suppressing combustion depending on the method of supplying it onto the surface of the reacting forest combustible have been determined. Estimates have been made of the nonreacted portion of the material by comparing the initial mass of the sample of the forest combustible with its final mass (upon quenching the material).

Geochemistry and origins of mineralized waters in the Floridan aquifer system, northeastern Florida

USGS Publications Warehouse

Phelps, G.G.

2001-01-01

Increases in chloride concentration have been observed in water from numerous wells tapping the Floridan aquifer system in northeastern Florida. Although most increases have been in the eastern part of Duval County, Florida, no spatial pattern in elevated chloride concentrations is discernible. Possible sources of the mineralized water include modern seawater intrusion; unflushed Miocene-to-Pleistocene-age seawater or connate water in aquifer sediments; or mineralized water from deeper zones of the aquifer system or from formations beneath the Floridan aquifer system. The purpose of this study was to document the chemical and isotopic characteristics of water samples from various aquifer zones, and from geochemical and hydrogeologic data, to infer the source of the increased mineralization. Water samples were collected from 53 wells in northeastern Florida during 1997-1999. Wells tapped various zones of the aquifer including: the Fernandina permeable zone (FPZ), the upper zone of the Lower Floridan aquifer (UZLF), the Upper Floridan aquifer (UFA), and both the UFA and the UZLF. Water samples were analyzed for major ions and trace constituents and for isotopes of carbon, oxygen, hydrogen, sulfur, strontium, chlorine, and boron. Samples of rock from the aquifer were analyzed for isotopes of oxygen, carbon, and strontium. In general, water from various aquifer zones cannot be differentiated based on chemistry, except for water from FPZ wells. Major-ion concentrations vary as much within the upper zone of the Lower Floridan aquifer and the Upper Floridan aquifer as between these two zones. Simple models of mixing between fresh ground water and either modern seawater or water from the FPZ as a mineralized end member show that many water samples from the UZLF aquifer and the UFA are enriched in bicarbonate, calcium, magnesium, sulfate, fluoride, and silica and are depleted in sodium and potassium (as compared to concentrations predicted by simple mixing). Chemical mass-balance models of mixing and reactions between a hypothetical initial seawater and aquifer minerals cannot account for the observed water chemistry in a few wells, implying a source other than seawater, either ancient or modern, or the occurrence of other more complex rock-water reactions. Hydrogeologic and geochemical data from water and aquifer samples indicate that the most likely source of mineralized water in some wells yielding water with increasing chloride concentrations is water from the FPZ. In other wells, the flushing of Miocene-to-Pleistocene-age seawater can account for the observed chloride concentrations. The fact that most of the water samples collected are a mixture of less than one percent of mineralized water with more than 99 percent fresh or recharge water makes identifying the source of the mineralized water difficult. Differences in carbon-14 and sulfur-34 values probably reflect areal differences in aquifer mineralogy and distribution of organic carbon related to paleokarst features. Geochemical mass-balance models of seawater-rock interaction are unable to account for the chemical and isotopic composition of mineralized water from the FPZ, which implies another source of mineralized water, such as a brine, or the occurrence of more complex water-rock reactions.

Zero-power autonomous buoyancy system controlled by microbial gas production

NASA Astrophysics Data System (ADS)

Wu, Peter K.; Fitzgerald, Lisa A.; Biffinger, Justin C.; Spargo, Barry J.; Houston, Brian H.; Bucaro, Joseph A.; Ringeisen, Bradley R.

2011-05-01

A zero-power ballast control system that could be used to float and submerge a device solely using a gas source was built and tested. This system could be used to convey sensors, data loggers, and communication devices necessary for water quality monitoring and other applications by periodically maneuvering up and down a water column. Operational parameters for the system such as duration of the submerged and buoyant states can be varied according to its design. The gas source can be of any origin, e.g., compressed air, underwater gas vent, gas produced by microbes, etc. The zero-power ballast system was initially tested using a gas pump and further tested using gas produced by Clostridium acetobutylicum. Using microbial gas production as the only source of gas and no electrical power during operation, the system successfully floated and submerged periodically with a period of 30 min for at least 24 h. Together with microbial fuel cells, this system opens up possibilities for underwater monitoring systems that could function indefinitely.

Engineering of a highly efficient Xe₂*-excilamp (xenon excimer lamp, λmax=172 nm, η=40%) and qualitative comparison to a low-pressure mercury lamp (LP-Hg, λ=185/254 nm) for water purification.

PubMed

Al-Gharabli, Samer; Engeßer, Patrick; Gera, Diana; Klein, Sandra; Oppenländer, Thomas

2016-02-01

Excilamps are mercury-free gas-discharge sources of non-coherent VUV or UV radiation with high radiant power and a long lifetime. The most efficient excilamp that is currently available on the market is a VUV xenon excilamp system (Xe2(*)-excimer lamp, λ(max) = 172 nm) with a stated radiant efficiency η of 40% at an electrical input power P(el) of 20 W, 50 W or 100 W. In this paper, the use of this highly efficient Xe2(*)-excilamp (P(el) = 20 W) for water treatment is demonstrated using a recirculating laboratory photoreactor system with negative radiation geometry. The efficiency in the 172 nm initiated bleaching of aqueous solutions of Rhodamine B is compared to that initiated by a common low-pressure mercury (LP-Hg) lamp (185 nm, TNN 15/32). The dependence of the pseudo zero order rate constant k´ of decolorization of RhB on the flow rate and on the initial concentration of RhB was investigated. Both lamps exhibited dependences of k´ on the initial concentration of RhB, which represents a typical saturation kinetical behavior. The saturation kinetics was very prominent in the case of the Xe2(*)-excilamp. Also, the Xe2(*)-excilamp treatment exhibited a significant influence on the flow rate of the RhB aqueous solution, which was not the case during the LP-Hg lamp initiated bleaching of RhB. The results of this paper demonstrate that Xe2(*)-excilamps can be used for VUV-initiated water purification. However, to reach the maximum efficacy of the Xe2(*)-excilamp for photo-initiated water purification further engineering optimization of the photoreactor concept is necessary. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evidence for debris flow gully formation initiated by shallow subsurface water on Mars

USGS Publications Warehouse

Lanza, N.L.; Meyer, G.A.; Okubo, C.H.; Newsom, Horton E.; Wiens, R.C.

2010-01-01

The morphologies of some martian gullies appear similar to terrestrial features associated with debris flow initiation, erosion, and deposition. On Earth, debris flows are often triggered by shallow subsurface throughflow of liquid water in slope-mantling colluvium. This flow causes increased levels of pore pressure and thus decreased shear strength, which can lead to slide failure of slope materials and subsequent debris flow. The threshold for pore pressure-induced failure creates a distinct relationship between the contributing area supplying the subsurface flow and the slope gradient. To provide initial tests of a similar debris flow initiation hypothesis for martian gullies, measurements of the contributing areas and slope gradients were made at the channel heads of martian gullies seen in three HiRISE stereo pairs. These gullies exhibit morphologies suggestive of debris flows such as leveed channels and lobate debris fans, and have well-defined channel heads and limited evidence for multiple flows. Our results show an area-slope relationship for these martian gullies that is consistent with that observed for terrestrial gullies formed by debris flow, supporting the hypothesis that these gullies formed as the result of saturation of near-surface regolith by a liquid. This model favors a source of liquid that is broadly distributed within the source area and shallow; we suggest that such liquid could be generated by melting of broadly distributed icy materials such as snow or permafrost. This interpretation is strengthened by observations of polygonal and mantled terrain in the study areas, which are both suggestive of near-surface ice. ?? 2009 Elsevier Inc.

Developing a Small-Scale De-Fluoridation Filter for Use in Rural Northern Ghana with Activated Alumina As the Sorbent

NASA Astrophysics Data System (ADS)

Craig, L.; Stillings, L. L.

2014-12-01

In northern Ghana, groundwater is the main source of household water and is generally considered safe to drink. However in some areas it contains fluoride (F-) concentrations above the 1.5 ppm limit recommended by the World Health Organization, putting the users at risk of fluorosis. The study area in the Upper East Region of Ghana has pockets of groundwater F- up to 4.6 ppm and, as a result, also has a high percentage of residents with dental fluorosis. They have no alternative water source and, because of poverty and limited access to technology, lack the capacity to set up advanced treatment systems. One proposed solution is to attach F- adsorption filters to the wells, since adsorption is considered a simple and cost effective approach for treating high F-drinking water. This study evaluates activated alumina as a sorbent for use in de-fluoridation filters in the study area. We evaluated the long-term adsorption capacity of activated alumina, and changes in F- adsorption rate and capacity with grain size. We measured differences in positive surface charge (C m-2) via slow acid titration, as well as F- loading with varied prior hydration time. Results from this research show no notable change in F- adsorption or positive surface charge when the activated alumina surface was pre-equilibrated in distilled water from 24 hours to 30 weeks. The results of F- loading show a maximum of ~3.4 mg F- sorbed per gm activated alumina (initial pH ~6.9, initial F- 1 to 60 ppm, 20 hr reaction time). The pH dependent surface charge is ~0.14 C m-2 at pH of ~4.4 and is zero at pH ~8.6. F- loading experiments were conducted with grain size 0.125 to 0.250 mm and 0.5 to 1.0 mm to evaluate changes in F- adsorption rate (initial pH ~6.9, initial F- 10 ppm) and F- loading (initial pH ~6.9, initial F- 1 to 60 ppm, 20 hr reaction time). The F- loading did not change with grain size. However time to equilibrium increased dramatically with a decrease in grain size - after one hour of reaction time, the larger grain size adsorbed only 59% of F-, while at the finer grain size 90% was adsorbed. Future work will determine the volume of high F- water that can be treated before activated alumina needs to be regenerated or changed. These data will aid in the design of a small-scale F- adsorption filter in the study area, and will predict the longevity of activated alumina as the sorbent.

Understanding beach health throughout the Great Lakes -- continuing research

USGS Publications Warehouse

,

2012-01-01

The overall mission of U.S. Geological Survey (USGS) Beach Health Initiative is to provide science-based information and methods that will allow beach managers to more accurately make beach closure and advisory decisions, understand the sources and physical processes affecting beach contaminants, and understand how science-based information can be used to mitigate and restore beaches and protect the public. The USGS, in collaboration with many Federal, State, and local agencies and universities, has conducted research on beach-health issues in the Great Lakes Region for more than a decade. The work consists of four science elements that align with the initiative's mission: real-time assessments of water quality; coastal processes; pathogens and source tracking; and data analysis, interpretation, and communication. The ongoing or completed research for each of these elements is described in this fact sheet.

Land-based sources of marine pollution: Pesticides, PAHs and phthalates in coastal stream water, and heavy metals in coastal stream sediments in American Samoa.

PubMed

Polidoro, Beth A; Comeros-Raynal, Mia T; Cahill, Thomas; Clement, Cassandra

2017-03-15

The island nations and territories of the South Pacific are facing a number of pressing environmental concerns, including solid waste management and coastal pollution. Here we provide baseline information on the presence and concentration of heavy metals and selected organic contaminants (pesticides, PAHs, phthalates) in 7 coastal streams and in surface waters adjacent to the Futiga landfill in American Samoa. All sampled stream sediments contained high concentrations of lead, and some of mercury. Several coastal stream waters showed relatively high concentrations of diethyl phthalate and of organophosphate pesticides, above chronic toxicity values for fish and other aquatic organisms. Parathion, which has been banned by the US Environmental Protection Agency since 2006, was detected in several stream sites. Increased monitoring and initiatives to limit non-point source land-based pollution will greatly improve the state of freshwater and coastal resources, as well as reduce risks to human health in American Samoa. Copyright © 2016 Elsevier Ltd. All rights reserved.

Typhoid outbreak investigation in Dzivaresekwa, suburb of Harare City, Zimbabwe, 2011.

PubMed

Muti, Monica; Gombe, Notion; Tshimanga, Mufuta; Takundwa, Lucia; Bangure, Donewell; Mungofa, Stanley; Chonzi, Prosper

2014-01-01

Typhoid fever is a systemic infection caused by a Gram negative bacterium, Salmonella typhi. Harare City reported 1078 cases of suspected typhoid fever cases from October 2011 to January 2012. We initiated an investigation to identify possible source of transmission so as to institute control measures. An unmatched 1:1 case-control study was conducted. A questionnaire was administered to study participants to identify risk factors for contracting typhoid. A case was a resident of Dzivaresekwa who presented with signs and symptoms of typhoid between October and December 2011. Water samples were collected for microbiological analysis. 115 cases and 115 controls were enrolled. Drinking water from a well (OR=6.2 95% CI (2.01-18.7)), attending a gathering (OR=11.3 95% CI (4.3-29.95)), boiling drinking water (OR=0.21 95% CI (0.06-0.76)) and burst sewer pipe at home (OR=1.19 95% CI (0.67-2.14)) were factors associated with contracting typhoid. Independent risk factors for contracting typhoid were drinking water from a well (AOR=5.8; 95% CI (1.90-17.78)), and burst sewer pipe at home (AOR=1.20; 95% CI (1.10-2.19)). Faecal coli forms and E. coli were isolated from 8/8 well water samples. Stool, urine and blood specimens were cultured and serotyped for Salmonella typhi and 24 cases were confirmed positive. Shigella, Giardia and E coli were also isolated. Ciprofloxacin, X-pen and Rocephin were used for case management. No complications were reported. Contaminated water from unprotected water sources was the probable source of the outbreak. Harare City Engineer must invest in repairing water and sewage reticulation systems in the city.

Large CO2 and CH4 release from a flooded formerly drained fen

NASA Astrophysics Data System (ADS)

Sachs, T.; Franz, D.; Koebsch, F.; Larmanou, E.; Augustin, J.

2016-12-01

Drained peatlands are usually strong carbon dioxide (CO2) sources. In Germany, up to 4.5 % of the national CO2 emissions are estimated to be released from agriculturally used peatlands and for some peatland-rich northern states, such as Mecklenburg-Western Pomerania, this share increases to about 20%. Reducing this CO2 source and restoring the peatlands' natural carbon sink is one objective of large-scale nature protection and restoration measures, in which 37.000 ha of drained and degraded peatlands in Mecklenburg-Western Pomerania are slated for rewetting. It is well known, however, that in the initial phase of rewetting, a reduction of the CO2 source strength is usually accompanied by an increase in CH4 emissions. Thus, whether and when the intended effects of rewetting with regard to greenhouse gases are achieved, depends on the balance of CO2 and CH4 fluxes and on the duration of the initial CH4 emission phase. In 2013, a new Fluxnet site went online at a flooded formerly drained river valley fen site near Zarnekow, NE Germany (DE-Zrk), to investigate the combined CO2 and CH4 dynamics at such a heavily degraded and rewetted peatland. The site is dominated by open water with submerged and floating vegetation and surrounding Typha latifolia.Nine year after rewetting, we found large CH4 emissions of 53 g CH4 m-2 a-1 from the open water area, which are 4-fold higher than from the surrounding vegetation zone (13 g CH4 m-2 a-1). Surprisingly, both the open water and the vegetated area were net CO2 sources of 158 and 750 g CO2 m-2 a-1, respectively. Unusual meteorological conditions with a warm and dry summer and a mild winter might have facilitated high respiration rates, particularly from temporally non-inundated organic mud in the vegetation zone.

Benthic nutrient sources to hypereutrophic Upper Klamath Lake, Oregon, USA

USGS Publications Warehouse

Kuwabara, J.S.; Topping, B.R.; Lynch, D.D.; Carter, J.L.; Essaid, H.I.

2009-01-01

Three collecting trips were coordinated in April, May, and August 2006 to sample the water column and benthos of hypereutrophic Upper Klamath Lake (OR, USA) through the annual cyanophyte bloom of Aphanizomenon flos-aquae. A porewater profiler was designed and fabricated to obtain the first high-resolution (centimeter-scale) estimates of the vertical, concentration gradients of macro- and micronutrients for diffusive-flux determinations. A consistently positive benthic flux for soluble reactive phosphorus (SRP) was observed with solute release from the sediment, ranging between 0.4 and 6.1 mg/m2/d. The mass flux over an approximate 200-km2 lake area was comparable in magnitude to riverine inputs. An additional concern, related to fish toxicity was identified when dissolved ammonium also displayed consistently positive benthic fluxes of 4 to 134 mg/m2/d, again, comparable to riverine inputs. Although phosphorus was a logical initial choice by water quality managers for the limiting nutrient when nitrogen-fixing cyanophytes dominate, initial trace-element results from the lake and major inflowing tributaries suggested that the role of iron limitation on primary productivity should be investigated. Dissolved iron became depleted in the lake water column during the course of the algal bloom, while dissolved ammonium and SRP increased. Elevated macroinvertebrate densities, at least of the order of 104 individuals/m2, suggested, that the diffusive-flux estimates may be significantly enhanced, by bioturbation. In addition, heat-flux modeling indicated that groundwater advection of nutrients could also significantly contribute to internal nutrient loading. Accurate environmental assessments of lentic systems and reasonable expectations for point-source management require quantitative consideration of internal solute sources ?? 2009 SETAC.

FREEWAT: an HORIZON 2020 project to build open source tools for water management.

NASA Astrophysics Data System (ADS)

Foglia, L.; Rossetto, R.; Borsi, I.; Mehl, S.; Velasco Mansilla, V.

2015-12-01

FREEWAT is an HORIZON 2020 EU project. FREEWAT main result will be an open source and public domain GIS integrated modelling environment for the simulation of water quantity and quality in surface water and groundwater with an integrated water management and planning module. FREEWAT aims at promoting water resource management by simplifying the application of the Water Framework Directive and related Directives. Specific objectives of the project are: to coordinate previous EU and national funded research to integrate existing software modules for water management in a single environment into the GIS based FREEWAT and to support the FREEWAT application in an innovative participatory approach gathering technical staff and relevant stakeholders (policy and decision makers) in designing scenarios for application of water policies. The open source characteristics of the platform allow to consider this an initiative "ad includendum", as further institutions or developers may contribute to the development. Core of the platform is the SID&GRID framework (GIS integrated physically-based distributed numerical hydrological model based on a modified version of MODFLOW 2005; Rossetto et al. 2013) in its version ported to QGIS desktop. Activities are carried out on two lines: (i) integration of modules to fulfill the end-users requirements, including tools for producing feasibility and management plans; (ii) a set of activities to fix bugs and to provide a well-integrated interface for the different tools implemented. Further capabilities to be integrated are: - module for water management and planning; - calibration, uncertainty and sensitivity analysis; - module for solute transport in unsaturated zone; - module for crop growth and water requirements in agriculture; - tools for groundwater quality issues and for the analysis, interpretation and visualization of hydrogeological data. Through creating a common environment among water research/professionals, policy makers and implementers, FREEWAT main impact will be on enhancing science- and participatory approach and evidence-based decision making in water resource management, hence producing relevant and appropriate outcomes for policy implementation. Large stakeholders involvement is thought to guarantee results dissemination and exploitation.

CERT tribal internship program. Final intern report: Duane Gopher, 1994

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

The Rocky Boy Indian Reservation in north-central Montana has had difficulty in establishing a dependable source of drinking water. In 1993, due to a water shortage on the Rocky Boy Reservation, the Chippewa-Cree Council began negotiating water rights with the State of Montana in order to construct a pipeline that would pump water from an off-reservation source to reservation homes. The proposed plan is to pipe water from the Tiber Dam, located approximately 53 miles west, to the Rocky Boy Indian Reservation for treatment and distribution. The purpose of this internship was to initiate a ground water investigation on themore » Rocky Boy Reservation by writing a report and submitting it to the Tribe. The intern undertook this project because he felt there was no need for an expensive pipeline and from familiarity with the Reservation, thought a dependable supply of drinking water may already exist on the Reservation. The intern obtained topographic maps from the USGS, requested well logs, conducted a literature survey, and requested planimetric maps from the Montana Bureau of Mines. The preliminary ground water report has been completed, but final results of the investigation are dependent upon the review by the Rocky Boy Tribal Council. This intern report contains biographical data on the intern and his mentor, as well as the completed preliminary report submitted to the Tribal Council.« less

Joint Estimation of Source Range and Depth Using a Bottom-Deployed Vertical Line Array in Deep Water

PubMed Central

Li, Hui; Yang, Kunde; Duan, Rui; Lei, Zhixiong

2017-01-01

This paper presents a joint estimation method of source range and depth using a bottom-deployed vertical line array (VLA). The method utilizes the information on the arrival angle of direct (D) path in space domain and the interference characteristic of D and surface-reflected (SR) paths in frequency domain. The former is related to a ray tracing technique to backpropagate the rays and produces an ambiguity surface of source range. The latter utilizes Lloyd’s mirror principle to obtain an ambiguity surface of source depth. The acoustic transmission duct is the well-known reliable acoustic path (RAP). The ambiguity surface of the combined estimation is a dimensionless ad hoc function. Numerical efficiency and experimental verification show that the proposed method is a good candidate for initial coarse estimation of source position. PMID:28590442

Simulation of fluid flow and energy transport processes associated with high-level radioactive waste disposal in unsaturated alluvium

USGS Publications Warehouse

Pollock, David W.

1986-01-01

Many parts of the Great Basin have thick zones of unsaturated alluvium which might be suitable for disposing of high-level radioactive wastes. A mathematical model accounting for the coupled transport of energy, water (vapor and liquid), and dry air was used to analyze one-dimensional, vertical transport above and below an areally extensive repository. Numerical simulations were conducted for a hypothetical repository containing spent nuclear fuel and located 100 m below land surface. Initial steady state downward water fluxes of zero (hydrostatic) and 0.0003 m yr−1were considered in an attempt to bracket the likely range in natural water flux. Predicted temperatures within the repository peaked after approximately 50 years and declined slowly thereafter in response to the decreasing intensity of the radioactive heat source. The alluvium near the repository experienced a cycle of drying and rewetting in both cases. The extent of the dry zone was strongly controlled by the mobility of liquid water near the repository under natural conditions. In the case of initial hydrostatic conditions, the dry zone extended approximately 10 m above and 15 m below the repository. For the case of a natural flux of 0.0003 m yr−1 the relative permeability of water near the repository was initially more than 30 times the value under hydrostatic conditions, consequently the dry zone extended only about 2 m above and 5 m below the repository. In both cases a significant perturbation in liquid saturation levels persisted for several hundred years. This analysis illustrates the extreme sensitivity of model predictions to initial conditions and parameters, such as relative permeability and moisture characteristic curves, that are often poorly known.

The Effects of Ashe Juniper on Groundwater Recharge in the Edwards Aquifer

NASA Astrophysics Data System (ADS)

Bazan, R. A.; Wilcox, B. P.; Munster, C. L.; Gregory, L. F.

2008-12-01

Understanding groundwater recharge rates has direct relevance for management of the Edwards Aquifer, which serves as the main source of fresh water for the city of San Antonio and surrounding communities. As population around San Antonio continues to grow, so does the demand for water and the stress placed on the aquifer. A method that is commonly believed to augment water yields is brush management. Recently on the Edwards Plateau decreasing streamflow has coincided with increasing juniper density. This has led many to believe that removing juniper would increase available water. Due to its karstic nature, the recharge zone of the Edwards Aquifer is assumed to be a prime location for augmenting water yields through vegetation manipulation. This study assesses the dynamics of recharge and the effects of manipulating surface vegetation. To accomplish this, a shallow cave located in the Edwards Aquifer recharge zone in San Antonio, Texas was instrumented to monitor drip recharge in response to simulated rainfall events. In 2004, simulations were conducted over the cave to measure recharge rates with a dense Ashe juniper canopy. The data and observations from the initial simulations were used to establish a baseline with the juniper in place. In March 2008 the juniper stand was cleared and the rainfall simulations were reproduced in June and July 2008. Results initially indicated that removing the juniper decreases recharge, however, surface runoff was significantly increased. From the results we can conclude that the dynamics of recharge are affected initially following removal of juniper.

FREEWAT: an HORIZON 2020 project to build open source tools for water management.

NASA Astrophysics Data System (ADS)

Rossetto, Rudy; Borsi, Iacopo; Foglia, Laura

2015-04-01

FREEWAT is an HORIZON 2020 project financed by the EU Commission under the call WATER INNOVATION: BOOSTING ITS VALUE FOR EUROPE. FREEWAT main result will be an open source and public domain GIS integrated modelling environment for the simulation of water quantity and quality in surface water and groundwater with an integrated water management and planning module. FREEWAT aims at promoting water resource management by simplifying the application of the Water Framework Directive and other EU water related Directives. Specific objectives of the FREEWAT project are: to coordinate previous EU and national funded research to integrate existing software modules for water management in a single environment into the GIS based FREEWAT and to support the FREEWAT application in an innovative participatory approach gathering technical staff and relevant stakeholders (in primis policy and decision makers) in designing scenarios for the proper application of water policies. The open source characteristics of the platform allow to consider this an initiative "ad includendum" (looking for inclusion of other entities), as further research institutions, private developers etc. may contribute to the platform development. The core of the FREEWAT platform will be the SID&GRID framework in its version ported to the QGIS desktop. SID&GRID (GIS integrated physically-based distributed numerical hydrological model based on a modified version of MODFLOW 2005; Rossetto et al. 2013) is an open source and public domain modelling platform firstly developed within the EU-POR FSE 2007-2013 Regione Toscana - Italy and then ported to the QGIS desktop through a dedicated fund by Regione Toscana. SID&GRID will be complemented by June 2015 with solute transport (also density dependent) capabilities in aquifers within the MARSOL (2014) EU FPVII project. Activities will be mainly carried out on two branches: (i) integration of modules, so that the software will fit the end-users requirements, including tools for better producing feasibility and management plans; (ii) a set of activities devoted to fix bugs and to provide a well-integrated interface for the different tools implemented. Further capabilities to be integrated are: - a dedicated module for water management and planning that will help to manage and aggregate all the distributed data coming from the simulation scenarios; - a whole module for calibration, uncertainty and sensitivity analysis; - a module for solute transport in the unsaturated zone; - a module for crop growth and water requirements in agriculture; - tools for dealing with groundwater quality issues; - tools for the analysis, interpretation and visualization of hydrogeological data. Through creating a common environment among water research/professionals, policy makers and implementers, FREEWAT main impact will be on enhancing science- and participatory approach and evidence-based decision making in water resource management, hence producing relevant and appropriate outcomes for policy implementation. The Consortium is constituted by partners from various water sectors from 10 EU countries, plus Turkey and Ukraine. Synergies with the UNESCO HOPE initiative on free and open source software in water management greatly boost the value of the project. Large stakeholders involvement is thought to guarantee results dissemination and exploitation. Acknowledgements This paper is presented within the framework of the project FREEWAT, which has received funding from the European Union's Horizon 2020 research and innovation programme under Grant Agreement n. 642224. References MARSOL (2014). Demonstrating Managed Aquifer Recharge as a Solution to Water Scarcity and Drought www.marsol.eu [accessed 4 January 2015] Rossetto, R., Borsi, I., Schifani, C., Bonari, E., Mogorovich P. & Primicerio M. (2013) - SID&GRID: integrating hydrological modeling in GIS environment hydroinformatics system for the management of the water resource. Rendiconti Online Societa Geologica Italiana Volume 24, 282-283

Non-local drivers of the summer hypoxia in the East China Sea off the Changjiang Estuary

NASA Astrophysics Data System (ADS)

Qian, Wei; Dai, Minhan; Xu, Min; Kao, Shuh-ji; Du, Chuanjun; Liu, Jinwen; Wang, Hongjie; Guo, Liguo; Wang, Lifang

2017-11-01

The East China Sea (ECS) off the Changjiang (Yangtze River) Estuary, located around the near field of the Changjiang plume (CJP) is a hot spot where phytoplankton blooms in the surface water and hypoxias in the subsurface/bottom waters are frequently observed. Based on field observations conducted in summer 2009 and 2011, we examined non-local drivers associated with the initial dissolved oxygen (DO) levels that had significant impact on the development of summer hypoxias in the ECS off the Changjiang Estuary. The bottom water mass therein could be traced isopycnally at 24.2 < σθ < 25.2 back to the vicinity of the Luzon Strait, ∼1300 km upstream, where subsurface Kuroshio water (∼220 m deep with ∼190 μmol DO kg-1) mixed with the South China Sea subsurface water (∼120 m deep with ∼130 μmol DO kg-1). Owing to the difference in DO of these two source water masses, their mixing ratio ultimately determined the initial DO supply to the ECS bottom water that eventually reached the hypoxic zone. This water mass mixture was also subject to biogeochemical alteration during its travel (∼60 days) after it intruded into the ECS at the northeastern tip of Taiwan. Along the pathway of the intruded bottom-hugging water, we found systematic increases in nutrient concentrations and apparent oxygen utilization, or drawdown in DO following Redfield stoichiometry as a result of marine organic matter decomposition. These non-local factors exerted a synergistic control on the initial DO of CJP bottom water promoting hypoxia formation, although the residence time of the CJP bottom water was relatively short (∼11 days). We contend that such far field drivers should be taken into account in order to better predict the future scenarios of coastal hypoxias in the context of global warming.

High-resolution seismic reflection survey at Dover AFB: A comparison of three seismic sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cardimona, S.; Kadinsky-Cade, K.; Miller, R.

1996-11-01

In June of 1995, the Earth Sciences Division of the Air Force Phillips Lab, with survey equipment from the University of Delaware and assisted by the Kansas Geological Survey and Elohi Geophysics, conducted a geophysical site characterization of the SERDP-funded Groundwater Remediation Field Lab (GRFL) located at Dover AFB, Delaware and administered by Applied Research Associates for USAF Armstrong Lab. Seismic data were collected in order to (1) compare the results using three different compressional sources and (2) cover the field site well enough to characterize the seismic response of the shallow subsurface. This paper will focus primarily on themore » first of these two goals. Seismic data were collected along three north-south profiles set 10 meters apart, each profile with a different compressional source: a 5.5kg sledgehammer, a 12-gauge firing rod from Betsy Seisgun Inc. shooting 150 grain blanks, and a portable piezoelectrically driven vibrator, developed by Elohi Geophysics, operating with a 90Hz-450Hz sweep. An east-west cross line was collected using the sledgehammer source in order to tie the three profiles together. A laser theodolite provided station location and elevation control. The primary targets were the water table (that had been marked on maps at a depth of about 3 meters) and a sand-clay interface at about 15 meters depth. We collected 24-channel CMP data using a half meter spacing of both source and 100Hz geophones. Field C after initial walkaway noise testing with each source did not show any one source to be outstanding A practical early result of the seismic survey showed the water table to be at just over 10 meters. We have associated the strongest reflection event with the water-table interface. Seismic data comparison in this study is based on spectral content, total energy and signal-to-noise ratios, as well as a discussion of coherency of the primary reflection event at the water table.« less

Production of Methane and Water from Crew Plastic Waste

NASA Technical Reports Server (NTRS)

Captain, Janine; Santiago, Eddie; Parrish, Clyde; Strayer, Richard F.; Garland, Jay L.

2008-01-01

Recycling is a technology that will be key to creating a self sustaining lunar outpost. The plastics used for food packaging provide a source of material that could be recycled to produce water and methane. The recycling of these plastics will require some additional resources that will affect the initial estimate of starting materials that will have to be transported from earth, mainly oxygen, energy and mass. These requirements will vary depending on the recycling conditions. The degredation products of these plastics will vary under different atmospheric conditions. An estimate of the the production rate of methane and water using typical ISRU processes along with the plastic recycling will be presented.

Theoretical and Numerical Modeling of Transport of Land Use-Specific Fecal Source Identifiers

NASA Astrophysics Data System (ADS)

Bombardelli, F. A.; Sirikanchana, K. J.; Bae, S.; Wuertz, S.

2008-12-01

Microbial contamination in coastal and estuarine waters is of particular concern to public health officials. In this work, we advocate that well-formulated and developed mathematical and numerical transport models can be combined with modern molecular techniques in order to predict continuous concentrations of microbial indicators under diverse scenarios of interest, and that they can help in source identification of fecal pollution. As a proof of concept, we present initially the theory, numerical implementation and validation of one- and two-dimensional numerical models aimed at computing the distribution of fecal source identifiers in water bodies (based on Bacteroidales marker DNA sequences) coming from different land uses such as wildlife, livestock, humans, dogs or cats. These models have been developed to allow for source identification of fecal contamination in large bodies of water. We test the model predictions using diverse velocity fields and boundary conditions. Then, we present some preliminary results of an application of a three-dimensional water quality model to address the source of fecal contamination in the San Pablo Bay (SPB), United States, which constitutes an important sub-embayment of the San Francisco Bay. The transport equations for Bacteroidales include the processes of advection, diffusion, and decay of Bacteroidales. We discuss the validation of the developed models through comparisons of numerical results with field campaigns developed in the SPB. We determine the extent and importance of the contamination in the bay for two decay rates obtained from field observations, corresponding to total host-specific Bacteroidales DNA and host-specific viable Bacteroidales cells, respectively. Finally, we infer transport conditions in the SPB based on the numerical results, characterizing the fate of outflows coming from the Napa, Petaluma and Sonoma rivers.

Initial environmental impacts of the Obed Mountain coal mine process water spill into the Athabasca River (Alberta, Canada).

PubMed

Cooke, Colin A; Schwindt, Colin; Davies, Martin; Donahue, William F; Azim, Ekram

2016-07-01

On October 31, 2013, a catastrophic release of approximately 670,000m(3) of coal process water occurred as the result of the failure of the wall of a post-processing settling pond at the Obed Mountain Mine near Hinton, Alberta. A highly turbid plume entered the Athabasca River approximately 20km from the mine, markedly altering the chemical composition of the Athabasca River as it flowed downstream. The released plume traveled approximately 1100km downstream to the Peace-Athabasca Delta in approximately four weeks, and was tracked both visually and using real-time measures of river water turbidity within the Athabasca River. The plume initially contained high concentrations of nutrients (nitrogen and phosphorus), metals, and polycyclic aromatic hydrocarbons (PAHs); some Canadian Council of Ministers of the Environmental (CCME) Guidelines were exceeded in the initial days after the spill. Subsequent characterization of the source material revealed elevated concentrations of both metals (arsenic, lead, mercury, selenium, and zinc) and PAHs (acenaphthene, fluorene, naphthalene, phenanthrene, and pyrene). While toxicity testing using the released material indicated a relatively low or short-lived acute risk to the aquatic environment, some of the water quality and sediment quality variables are known carcinogens and have the potential to exert negative long-term impacts. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Speciation and formation of iodinated trihalomethane from microbially derived organic matter during the biological treatment of micro-polluted source water.

PubMed

Wei, Yuanyuan; Liu, Yan; Ma, Luming; Wang, Hongwu; Fan, Jinhong; Liu, Xiang; Dai, Rui-Hua

2013-09-01

Water sources are micro-polluted by the increasing range of anthropogenic activities around them. Disinfection byproduct (DBP) precursors in water have gradually expanded from humic acid (HA) and fulvic acid to other important sources of potential organic matter. This study aimed to provide further insights into the effects of microbially derived organic matter as precursors on iodinated trihalomethane (I-THM) speciation and formation during the biological treatment of micro-polluted source water. The occurrence of I-THMs in drinking water treated by biological processes was investigated. The results showed for the first time that CHCl2I and CHBrClI are emerging DBPs in China. Biological pre-treatment and biological activated carbon can increase levels of microbes, which could serve as DBP precursors. Chlorination experiments with bovine serum albumin (BSA), starch, HA, deoxyribonucleic acid (DNA), and fish oil, confirmed the close correlation between the I-THM species identified during the treatment processes and those predicted from the model compounds. The effects of iodide and bromide on the I-THM speciation and formation were related to the biochemical composition of microbially derived organic precursors. Lipids produced up to 16.98μgL(-1) of CHCl2I at an initial iodide concentration of 2mgL(-1). HA and starch produced less CHCl2I at 3.88 and 3.54μgL(-1), respectively, followed by BSA (1.50μgL(-1)) and DNA (1.35μgL(-1)). Only fish oil produced I-THMs when iodide and bromide were both present in solution; the four other model compounds formed brominated species. Copyright © 2013 Elsevier Ltd. All rights reserved.

Wildfire effects on source-water quality--Lessons from Fourmile Canyon fire, Colorado, and implications for drinking-water treatment

USGS Publications Warehouse

Writer, Jeffrey H.; Murphy, Sheila F.

2012-01-01

Forested watersheds provide high-quality source water for many communities in the western United States. These watersheds are vulnerable to wildfires, and wildfire size, fire severity, and length of fire season have increased since the middle 1980s (Westerling and others, 2006). Burned watersheds are prone to increased flooding and erosion, which can impair water-supply reservoirs, water quality, and drinking-water treatment processes. Limited information exists on the degree, timing, and duration of the effects of wildfire on water quality, making it difficult for drinking-water providers to evaluate the risk and develop management options. In order to evaluate the effects of wildfire on water quality and downstream ecosystems in the Colorado Front Range, the U.S. Geological Survey initiated a study after the 2010 Fourmile Canyon fire near Boulder, Colorado. Hydrologists frequently sampled Fourmile Creek at monitoring sites upstream and downstream of the burned area to study water-quality changes during hydrologic conditions such as base flow, spring snowmelt, and summer thunderstorms. This fact sheet summarizes principal findings from the first year of research. Stream discharge and nitrate concentrations increased downstream of the burned area during snowmelt runoff, but increases were probably within the treatment capacity of most drinking-water plants, and limited changes were observed in downstream ecosystems. During and after high-intensity thunderstorms, however, turbidity, dissolved organic carbon, nitrate, and some metals increased by 1 to 4 orders of magnitude within and downstream of the burned area. Increases of such magnitude can pose problems for water-supply reservoirs, drinking-water treatment plants, and downstream aquatic ecosystems.

Source Water Protection Basics

EPA Pesticide Factsheets

Defines drinking water sources (source water), identifies drinking water sources, and describes source water assessments and protection, roles of government and organizations in drinking water source protection

Granular flows at recurring slope lineae on Mars indicate a limited role for liquid water

NASA Astrophysics Data System (ADS)

Dundas, Colin M.; McEwen, Alfred S.; Chojnacki, Matthew; Milazzo, Moses P.; Byrne, Shane; McElwaine, Jim N.; Urso, Anna

2017-12-01

Recent liquid water flow on Mars has been proposed based on geomorphological features, such as gullies. Recurring slope lineae — seasonal flows that are darker than their surroundings — are candidate locations for seeping liquid water on Mars today, but their formation mechanism remains unclear. Topographical analysis shows that the terminal slopes of recurring slope lineae match the stopping angle for granular flows of cohesionless sand in active Martian aeolian dunes. In Eos Chasma, linea lengths vary widely and are longer where there are more extensive angle-of-repose slopes, inconsistent with models for water sources. These observations suggest that recurring slope lineae are granular flows. The preference for warm seasons and the detection of hydrated salts are consistent with some role for water in their initiation. However, liquid water volumes may be small or zero, alleviating planetary protection concerns about habitable environments.

Granular flows at recurring slope lineae on Mars indicate a limited role for liquid water

USGS Publications Warehouse

Dundas, Colin M.; McEwen, Alfred S.; Chojnacki, Matthew; Milazzo, Moses; Byrne, Shane; McElwaine, Jim; Urso, Anna

2017-01-01

Recent liquid water flow on Mars has been proposed based on geomorphological features, such as gullies. Recurring slope lineae — seasonal flows that are darker than their surroundings — are candidate locations for seeping liquid water on Mars today, but their formation mechanism remains unclear. Topographical analysis shows that the terminal slopes of recurring slope lineae match the stopping angle for granular flows of cohesionless sand in active Martian aeolian dunes. In Eos Chasma, linea lengths vary widely and are longer where there are more extensive angle-of-repose slopes, inconsistent with models for water sources. These observations suggest that recurring slope lineae are granular flows. The preference for warm seasons and the detection of hydrated salts are consistent with some role for water in their initiation. However, liquid water volumes may be small or zero, alleviating planetary protection concerns about habitable environments.

Post audit of a numerical prediction of wellfield drawdown in a semiconfined aquifer system

USGS Publications Warehouse

Stewart, M.; Langevin, C.

1999-01-01

A numerical ground water flow model was created in 1978 and revised in 1981 to predict the drawdown effects of a proposed municipal wellfield permitted to withdraw 30 million gallons per day (mgd; 1.1 x 105 m3/day) of water from the semiconfined Floridan Aquifer system. The predictions are based on the assumption that water levels in the semiconfined Floridan Aquifer reach a long-term, steady-state condition within a few days of initiation of pumping. Using this assumption, a 75 day simulation without water table recharge, pumping at the maximum permitted rates, was considered to represent a worst-case condition and the greatest drawdowns that could be experienced during wellfield operation. This method of predicting wellfield effects was accepted by the permitting agency. For this post audit, observed drawdowns were derived by taking the difference between pre-pumping and post-pumping potentiometric surface levels. Comparison of predicted and observed drawdowns suggests that actual drawdown over a 12 year period exceeds predicted drawdown by a factor of two or more. Analysis of the source of error in the 1981 predictions suggests that the values used for transmissivity, storativity, specific yield, and leakance are reasonable at the wellfield scale. Simulation using actual 1980-1992 pumping rates improves the agreement between predicted and observed drawdowns. The principal source of error is the assumption that water levels in a semiconfined aquifer achieve a steady-state condition after a few days or weeks of pumping. Simulations using a version of the 1981 model modified to include recharge and evapotranspiration suggest that it can take hundreds of days or several years for water levels in the linked Surficial and Floridan Aquifers to reach an apparent steady-state condition, and that slow declines in levels continue for years after the initiation of pumping. While the 1981 'impact' model can be used for reasonably predicting short-term, wellfield-scale effects of pumping, using a 75 day long simulation without recharge to predict the long-term behavior of the wellfield was an inappropriate application, resulting in significant underprediction of wellfield effects.A numerical ground water flow model was created in 1978 and revised in 1981 to predict the drawdown effects of a proposed municipal wellfield permitted to withdraw 30 million gallons per day (mgd; 1.1??105 m3/day) of water from the semiconfined Floridan Aquifer system. The predictions are based on the assumption that water levels in the semiconfined Floridan Aquifer reach a long-term, steady-state condition within a few days of initiation of pumping. Using this assumption, a 75 day simulation without water table recharge, pumping at the maximum permitted rates, was considered to represent a worst-case condition and the greatest drawdowns that could be experienced during wellfield operation. This method of predicting wellfield effects was accepted by the permitting agency. For this post audit, observed drawdowns were derived by taking the difference between pre-pumping and post-pumping potentiometric surface levels. Comparison of predicted and observed drawdowns suggests that actual drawdown over a 12 year period exceeds predicted drawdown by a factor of two or more. Analysis of the source of error in the 1981 predictions suggests that the values used for transmissivity, storativity, specific yield, and leakance are reasonable at the wellfield scale. Simulation using actual 1980-1992 pumping rates improves the agreement between predicted and observed drawdowns. The principal source of error is the assumption that water levels in a semiconfined aquifer achieve a steady-state condition after a few days or weeks of pumping. Simulations using a version of the 1981 model modified to include recharge and evapotranspiration suggest that it can take hundreds of days or several years for water levels in the linked Surficial and Floridan Aquifers to reach an apparent stead

The Influence of Intensifying Irrigation on Glacier Mass Balances in High Mountain Asia

NASA Astrophysics Data System (ADS)

de Kok, R.; Tuinenburg, O.; Bonekamp, P. N. J.; Immerzeel, W. W.

2017-12-01

Melt water from snow and glaciers in High Mountain Asia provide a major source of water for millions of inhabitants in the downstream low lying plains. This densely populated region also hosts some of the largest areas of irrigated land in the world. Not only is the water from High Mountain Asia important as a source of irrigation water, the irrigation itself might also change the regional, and even global, climate by increasing atmospheric moisture and by cooling the surface through evapotranspiration. We explore the effect of irrigation in the region on the synoptic climate patterns in High Mountain Asia using the WRF regional climate model. By studying the changes in the energy balance, temperatures and precipitation, we assess how the changes in irrigation patterns may have contributed to the observed trends in mountain climates and associated glacier mass balances. Initial results show that the intensifying irrigation during the last decades causes an increase in summer snowfall in the mountains in Central Karakoram and Kunlun Shan, which are the regions where slight positive mass balances have been observed in recent years. A moisture tracking model confirms that the irrigated areas are a significant moisture source for summer precipitation in High Mountain Asia. These results thus suggest that irrigation may significantly influence glaciers in High Mountain Asia, especially in the regions of observed anomalous mass balance.

Methane Sources and Migration Mechanisms in Shallow Groundwaters in Parker and Hood Counties, Texas-A Heavy Noble Gas Analysis.

PubMed

Wen, Tao; Castro, M Clara; Nicot, Jean-Philippe; Hall, Chris M; Larson, Toti; Mickler, Patrick; Darvari, Roxana

2016-11-01

This study places constraints on the source and transport mechanisms of methane found in groundwater within the Barnett Shale footprint in Texas using dissolved noble gases, with particular emphasis on 84 Kr and 132 Xe. Dissolved methane concentrations are positively correlated with crustal 4 He, 21 Ne, and 40 Ar and suggest that noble gases and methane originate from common sedimentary strata, likely the Strawn Group. In contrast to most samples, four water wells with the highest dissolved methane concentrations unequivocally show strong depletion of all atmospheric noble gases ( 20 Ne, 36 Ar, 84 Kr, 132 Xe) with respect to air-saturated water (ASW). This is consistent with predicted noble gas concentrations in a water phase in contact with a gas phase with initial ASW composition at 18 °C-25 °C and it suggests an in situ, highly localized gas source. All of these four water wells tap into the Strawn Group and it is likely that small gas accumulations known to be present in the shallow subsurface were reached. Additionally, lack of correlation of 84 Kr/ 36 Ar and 132 Xe/ 36 Ar fractionation levels along with 4 He/ 20 Ne with distance to the nearest gas production wells does not support the notion that methane present in these groundwaters migrated from nearby production wells either conventional or using hydraulic fracturing techniques.

Measurement of Fukushima Aerosol Debris in Sequim and Richland, WA and Ketchikan, AK

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miley, Harry S.; Bowyer, Ted W.; Engelmann, Mark D.

2013-05-01

Aerosol collections were initiated at several locations by PNNL shortly after the Great East Japan Earthquake of May 2011. Aerosol samples were transferred to laboratory high-resolution gamma spectrometers for analysis. Similar to treaty monitoring stations operating across the Northern hemisphere, iodine and other isotopes which could be volatilized at high temperature were detected. Though these locations are not far apart, they have significant variations with respect to water, mountain-range placement, and local topography. Variation in computed source terms will be shown to bound the variability of this approach to source estimation.

The Border Environmental Health Initiative: Investigation of the Transboundary Santa Cruz Watershed

NASA Astrophysics Data System (ADS)

Norman, L. M.; Callegary, J. B.; van Riper, C.; Gray, F.; Paretti, N.; Villarreal, M.

2009-12-01

In the borderland region of the desert southwest, human health and the ecosystems upon which humans rely largely depend on the quality, quantity, and distribution of water resources. In the Santa Cruz River Watershed (SCW), located in the Arizona and Sonora, Mexico border region, surface water is scarce and unreliable, and, during much of the year, is composed of effluent from the local wastewater treatment plant. This makes groundwater the preferred and, consequently, primary source for industrial, agricultural, and domestic use. USGS scientists are using an integrative approach, incorporating the expertise of the Geography, Water, Biology, and Geology disciplines to identify risks to water resources in the SCW, and the potential for impacts to riparian ecosystems and ultimately, human health. This includes tracking organic and inorganic contaminants and their effects from sources to sinks in sediment, water, plants, and animals. Existing ground- and surface-water models will be used and modified to assess contaminant and sediment transport. Water quality, sediment, aquatic macro invertebrates, aquatic plants (macrophytes), algae, riparian grasses, fish, and birds will be sampled at five locations along the Santa Cruz River. Field sampling data will be obtained at sites that coincide with historical sampling programs. Site locations include (i.) the Santa Cruz River headwaters (which should be unaffected by downstream contaminant sources), (ii.) a tributary routed through an abandoned mining district, (iii.) a binational tributary that flows though highly urbanized areas, (iv.) effluent from the local wastewater treatment plant, and (v.) the downstream confluence of the first four sources. The Soil and Water Assessment Tool (SWAT) model will be used in combination with field data to identify key sources of contaminants, contributing areas, and transport modes to track their movement to surface waters. These data will be used together to test relationships between sediment and hydrologic parameters, for the purpose of determining functional links. Further, it is planned that estimates of runoff and evapotranspiration resulting from the SWAT model simulations will be used to modify boundary conditions in the groundwater flow model to improve understanding of the effects of human activities on aquifer dynamics and contaminant transport. The SWAT model will then be used to identify critical sub-watersheds where implementing management practices could be most effective to abate pollution. An overview of our study design and preliminary results will be presented.

Installation-restoration program. Phase 2. Confirmation/quantification. Stage 1 for Shaw Air Force Base, South Carolina. Final report, January 1984-October 1986

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alexander, W.J.; Liddle, S.K.

1986-09-01

The primary objectives of this project were to collect and analyze groundwater, surface water, and sediment samples and to perform an initial characterization of the hydrogeochemical regime at potential contamination sites on Shaw Air Force Base near Sumter, South Carolina. This study constituted Phase II of the U.S. Air Force Installation Restoration Program (IRP). Five potential sources of groundwater pollution were studied. The evaluation primarily included the drilling of soil test borings, the installation, development, and sampling of groundwater monitoring wells, and the analyses of soil, surface water, and groundwater samples. Also used in the study were field measurements ofmore » water quality, water-level measurements site observations, published hydrogeologic data and Shaw AFB documents.« less

Low Evapotranspiration Enhances the Resilience of Peatland Carbon Stocks to Fire

NASA Astrophysics Data System (ADS)

Kettridge, N.; Lukenbach, M. C.; Hokanson, K. J.; Hopkinson, C.; Devito, K. J.; Petrone, R. M.; Mendoza, C. A.; Waddington, J. M.

2017-09-01

Boreal peatlands may be vulnerable to projected changes in the wildfire regime under future climates. Extreme drying during the sensitive postfire period may exceed peatland ecohydrological resilience, triggering long-term degradation of these globally significant carbon stocks. Despite these concerns, we show low peatland evapotranspiration at both the plot- and landscape-scale postfire, in water-limited peatlands dominated by feather moss that are ubiquitous across continental western Canada. Low postfire evapotranspiration enhances the resilience of carbon stocks in such peatlands to wildfire disturbance and reinforces their function as a regional source of water. Near-surface water repellency may provide an important, previously unexplored, regulator of peatland evapotranspiration that can induce low evapotranspiration in the initial postfire years by restricting the supply of water to the peat surface.

You cannot prevent a disease; you only treat diseases when they occur: knowledge, attitudes and practices to water-health in a rural Kenyan community.

PubMed

Levison, M M; Elliott, S J; Karanja, D M S; Schuster-Wallace, C J; Harrington, D W

2011-06-01

Almost 1 billion individuals lack access to improved water supplies, with 2.6 billion lacking adequate sanitation. This leads to the propagation of multiple waterborne diseases. The objective of this study was to explore local knowledge, attitudes and practices to understand the mechanisms and pre-conditions for sustainable uptake and use of these facilities. Data collection took place in a rural Kenyan community in September 2009. A qualitative approach was taken, with 4 focus groups and 25 in-depth interviews conducted. Participant characteristics varied by age, gender, education, marital status, employment and community standing. Few participants reported current access to improved water and sanitation facilities. Though they expressed desire for latrines and water sources, barriers including lack of funds and social capital, decrease the ability for installation. Participants understood that there was a link between the quality of water and their health, however, perceived benefits of current contaminated sources outweigh the potential health impacts and proliferate their continued use. While water-health links are understood to varying degrees within the community, contextual (physical environment), compositional (individual) and collective (community) factors interact to influence health. Community challenges, such as lack of unity, lack of education and lack control were identified as the main barriers to initiating change, despite a desire for increased access to safe water and sanitation.

The Global Society will need commodities; how do we prepare for the future?

NASA Astrophysics Data System (ADS)

Leahy, P. Patrick

2016-04-01

The global population currently stands at approximately 7 billion and is expected to increase to between 8.3 and 10.9 billion by 2050. To put this into perspective, today's global population is triple what it was in 1950. Commodities are required for healthy societies, for robust economies and to raise living standards in the developing world. With major increases the population particularly in nations with emerging economies, the demand for commodities such as water, energy and minerals will significantly increase during the next several decades. Among the concerns are clean and available freshwater, expanded energy sources from natural gas and nuclear to renewable energy, and emerging needs for specialty materials that are needed for advanced technology to expanded use of more conventional minerals for agriculture and commerce. The developing world may have the greatest need for these commodities and also be the source of many of them. At the conclusion of the International Year of Planet Earth, a small group was formed to assess the need for a major scientific effort in the geosciences. Under the auspices of the International Union of Geological Sciences (IUGS), the strategic initiatives group met and a broad initiative entitled 'Resourcing Future Generations' (RFG) that was designed to implement a scientific strategy to address the increasing demand for commodities over the next 25 years. The initiative focused on water resources, energy and minerals. The group felt strongly that the minerals component should be the initial emphasis and hoped that other global scientific organizations like IUGS would embrace the water and energy themes. Since this initial effort a number of workshops and presentations have been made including China, the International Geological Congress in Brisbane, the Davos Summit, Berlin, and Namibia amongst others. The strategic initiative planning group identifies 4 challenges to meeting future global mineral needs which are improved understanding of demand, discovery, extraction and social impact. RFG-Minerals consists of 4 major components: (1)understanding supply and demand, (2) gaining better knowledge of the subsurface, (3) improving technologies to safely and efficiently extract resources and (4) building social support and capacity in the developing world. This is ambitious effort that will require broad global collaboration across academia, government and industry.

Early Depositional History of the Eocene Izu-Bonin Mariana Arc, Western Pacific Ocean

NASA Astrophysics Data System (ADS)

Waldman, R.; Marsaglia, K. M.; Tepley, F. J., III

2015-12-01

Expedition 351 of the International Ocean Discovery Program cored an Eocene section at Site U1438 in the Philippine Sea that provides insight into the early history of the Izu-Bonin arc. Subduction here is hypothesized to have initiated spontaneously, leaving a characteristic depositional sequence of post-subduction-initiation localized extension and volcanism. We conducted detailed macroscopic and microscopic study of the cores of the lowermost 100m of volcaniclastic and sedimentary rocks (Unit IV) directly overlying subduction initiation igneous basement, to identify depositional facies and trends. We subdivided Unit IV into three subunits based on lithologic characteristics. Transitions between the subunits are relatively abrupt, occurring within the length of a single core. The lowermost subunit (IVA) consists of 4 meters of laminated pelagic claystone with thin beds of graded volcaniclastic siltstone, and fine-grained tuff laminae composed of plagioclase feldspar and green-brown amphibole. The middle subunit (IVB) comprises 51 meters of texturally variable, thick-bedded, coarse-grained gravity flow deposits. These are composed of volcaniclastic sandstone and conglomerate containing glassy and tachylitic volcanic grains as well as sedimentary lithic fragments, along with traces of shallow-water carbonate bioclasts. Subunit IVB sediments are poorer in feldspar than IVA and contain only trace amphibole. They show variable grain rounding and an upsection increase in vitric components. Tachylite grains range from sub-angular to well rounded throughout, and other volcanic grain types show upward increases in angularity and vesicularity. The abrupt transition from pelagic sediments in subunit IVA to shallow-water-sourced gravity flows in subunit IVB suggests a rapid emergence of shallow-water to subaerial volcanic center early in the arc's development. The upper part of subunit IVB also contains igneous intrusions, providing possible evidence for more proximal volcanism at the site. Subunit IVC consists of 46 meters of fine-grained turbidites composed of tuffaceous siltstone, along with radiolarian mudstone and vitric tuff layers. Ongoing studies of the volcanic components will provide additional insight into the source(s) of volcanics throughout the arc's early development.

Production of sugarcane and tropical grasses as a renewable energy source. Second annual report, 1978-1979

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1979-01-01

Reseach continued on tropical grasses from Saccharum and related genera as sources of intensively-produced, solar-dried biomass. Categories of candidate grasses include short-, intermediate-, and long-rotation species. These categories are based on the time interval required for maximum dry matter production, and on future management requirements of energy crops for intensive co-production with food crop commodities. Year 1 studies at the greenhouse and field-plot levels were continued and broadened during Year 2. This included candidate screening, importation and quarantine of new clones, breeding, controlled nitrogen and water regimes, chemical growth control, tissue expansion and maturation control, seeding rates, harvest frequency, andmore » variable row spacing. Second-year studies were extended to the project's field-scale and mechanized-harvest phases. These include initial economic anayses for the short-rotation phases. These include initial economic analyses for the short-rotation category of candidate species.« less

A new method of tree xylem water extraction for isotopic analysis

NASA Astrophysics Data System (ADS)

Gierke, C.; Newton, B. T.

2011-12-01

The Sacramento Mountain Watershed Study in the southern Sacramento Mountains of New Mexico is designed to assess the forest restoration technique of tree thinning in mountain watersheds as an effective method of increasing local and regional groundwater recharge. The project is using a soil water balance approach to quantify the partitioning of local precipitation within this watershed before and after thinning trees. Understanding what sources trees extract their water from (e.g. shallow groundwater, unsaturated fractured bedrock, and soils) is difficult due to a complex hydrologic system and heterogeneous distribution of soil thicknesses. However, in order to accurately quantify the soil water balance and to assess how thinning trees will affect this water balance, it is important determine the sources from which trees extract their water. We plan to use oxygen and hydrogen stable isotopic analysis of various end member waters to identify these different sources. We are in the process of developing a new method of determining the isotopic composition of tree water that has several advantages over conventional methods. Within the tree there is the xylem which transports water from the roots to the leaves and the phloem which transports starches and sugars in a water media throughout the tree. Previous studies have shown that the isotopic composition of xylem water accurately reflects that of source water, while phloem water has undergone isotopic fractionation during photosynthesis and metabolism. The distillation of water from twigs, which is often used to extract tree water for isotopic analysis, is very labor intensive. Other disadvantages to distillation methods include possible fractionation due to phase changes and the possible extraction of fractionated phloem waters. Employing a new mixing method, the composition of the twig water (TW) can be determined by putting twigs of unknown isotopic water composition into waters of known compositions or initial waters (IW), allowing diffusive processes to proceed to equilibrium, measuring the composition of the resulting mixture or final water (FW) then, solving a simple mixing equation. To evaluate this method, we collected several twig samples from Douglas Firs in the Sacramento Mountains. Twig water was prepared for isotopic analysis both by cryogenic distillation and the mixing method. Soil in close proximity to these trees was also sampled and water was extracted by cryogenic distillation. Preliminary results show that the isotopic composition of distilled twig water and soil waters plot to the right of the local meteoric water line (LMWL) suggesting that trees are extracting shallow evaporated soil water. Twig water obtained from the mixing method plot near the LMWL within the range expected for local snow melt, suggesting a possibly deeper non-evaporated source. In general, distillation values are approximately 4% heavier with respect to delta 18O than waters obtained from the mixing method. It is possible that this difference is due to the contribution of the fractionated water of the twig phloem that is released during the distillation process. This difference is quite significant and can lead to very different interpretations. These results are being addressed with additional experiments.

Addition of chlorine during water purification reduces iodine content of drinking water and contributes to iodine deficiency.

PubMed

Samson, L; Czegeny, I; Mezosi, E; Erdei, A; Bodor, M; Cseke, B; Burman, K D; Nagy, E V

2012-01-01

Drinking water is the major natural source of iodine in many European countries. In the present study, we examined possible sites of iodine loss during the usual water purification process.Water samples from 6 sites during the technological process were taken and analyzed for iodine content. Under laboratory circumstances, prepared iodine in water solution has been used as a model to test the effect of the presence of chlorine. Samples from the purification sites revealed that in the presence of chlorine there is a progressive loss of iodine from the water. In the chlorine concentrations employed in the purification process, 24-h chlorine exposure eliminated more than 50% of iodine when the initial iodine concentration was 250 μg/l or less. Iodine was completely eliminated if the starting concentration was 16 μg/l.We conclude that chlorine used during water purification may be a major contributor to iodine deficiency in European communities.

Identification of water quality degradation hotspots in developing countries by applying large scale water quality modelling

NASA Astrophysics Data System (ADS)

Malsy, Marcus; Reder, Klara; Flörke, Martina

2014-05-01

Decreasing water quality is one of the main global issues which poses risks to food security, economy, and public health and is consequently crucial for ensuring environmental sustainability. During the last decades access to clean drinking water increased, but 2.5 billion people still do not have access to basic sanitation, especially in Africa and parts of Asia. In this context not only connection to sewage system is of high importance, but also treatment, as an increasing connection rate will lead to higher loadings and therefore higher pressure on water resources. Furthermore, poor people in developing countries use local surface waters for daily activities, e.g. bathing and washing. It is thus clear that water utilization and water sewerage are indispensable connected. In this study, large scale water quality modelling is used to point out hotspots of water pollution to get an insight on potential environmental impacts, in particular, in regions with a low observation density and data gaps in measured water quality parameters. We applied the global water quality model WorldQual to calculate biological oxygen demand (BOD) loadings from point and diffuse sources, as well as in-stream concentrations. Regional focus in this study is on developing countries i.e. Africa, Asia, and South America, as they are most affected by water pollution. Hereby, model runs were conducted for the year 2010 to draw a picture of recent status of surface waters quality and to figure out hotspots and main causes of pollution. First results show that hotspots mainly occur in highly agglomerated regions where population density is high. Large urban areas are initially loading hotspots and pollution prevention and control become increasingly important as point sources are subject to connection rates and treatment levels. Furthermore, river discharge plays a crucial role due to dilution potential, especially in terms of seasonal variability. Highly varying shares of BOD sources across regions, and across sectors demand for an integrated approach to assess main causes of water quality degradation.

On the Effect of Dust Particles on Global Cloud Condensation Nuclei and Cloud Droplet Number

NASA Technical Reports Server (NTRS)

Karydis, V. A.; Kumar, P.; Barahona, D.; Sokolik, I. N.; Nenes, A.

2011-01-01

Aerosol-cloud interaction studies to date consider aerosol with a substantial fraction of soluble material as the sole source of cloud condensation nuclei (CCN). Emerging evidence suggests that mineral dust can act as good CCN through water adsorption onto the surface of particles. This study provides a first assessment of the contribution of insoluble dust to global CCN and cloud droplet number concentration (CDNC). Simulations are carried out with the NASA Global Modeling Initiative chemical transport model with an online aerosol simulation, considering emissions from fossil fuel, biomass burning, marine, and dust sources. CDNC is calculated online and explicitly considers the competition of soluble and insoluble CCN for water vapor. The predicted annual average contribution of insoluble mineral dust to CCN and CDNC in cloud-forming areas is up to 40 and 23.8%, respectively. Sensitivity tests suggest that uncertainties in dust size distribution and water adsorption parameters modulate the contribution of mineral dust to CDNC by 23 and 56%, respectively. Coating of dust by hygroscopic salts during the atmospheric aging causes a twofold enhancement of the dust contribution to CCN; the aged dust, however, can substantially deplete in-cloud supersaturation during the initial stages of cloud formation and can eventually reduce CDNC. Considering the hydrophilicity from adsorption and hygroscopicity from solute is required to comprehensively capture the dust-warm cloud interactions. The framework presented here addresses this need and can be easily integrated in atmospheric models.

Spatio-temporal evaluation of Yamchi Dam basin water quality using Canadian water quality index.

PubMed

Farzadkia, Mahdi; Djahed, Babak; Shahsavani, Esmaeel; Poureshg, Yousef

2015-04-01

In recent years, the growth of population and increase of the industries around the tributaries of Yamchi Dam basin have led to deterioration of dam water quality. This study aimed to evaluate the quality of the Yamchi Dam basin water, which is used for drinking and irrigation consumptions using Canadian Water Quality Index (CWQI) model, and to determine the main water pollution sources of this basin. Initially, nine sampling stations were selected in the sensitive locations of the mentioned basin's tributaries, and 12 physico-chemical parameters and 2 biological parameters were measured. The CWQI for drinking consumptions was under 40 at all the stations indicating a poor water quality for drinking consumptions. On the other hand, the CWQI was 62-100 for irrigation at different stations; thus, the water had an excellent to fair quality for irrigation consumptions. Almost in all the stations, the quality of irrigation and drinking water in cold season was better. Besides, for drinking use, total coliform and fecal coliform had the highest frequency of failure, and total coliform had the maximum deviation from the specified objective. For irrigation use, total suspended solids had the highest frequency of failure and deviation from the objective in most of the stations. The pisciculture center, aquaculture center, and the Nir City wastewater discharge were determined as the main pollution sources of the Yamchi Dam basin. Therefore, to improve the water quality in this important surface water resource, urban and industrial wastewater treatment prior to disposal and more stringent environmental legislations are recommended.

In Situ Characterization of the Initial Effect of Water on Molecular Interactions at the Interface of Organic/Inorganic Hybrid Systems

DOE PAGES

Pletincx, Sven; Trotochaud, Lena; Fockaert, Laura-Lynn; ...

2017-03-22

Probing initial interactions at the interface of hybrid systems under humid conditions has the potential to reveal the local chemical environment at solid/solid interfaces under real-world, technologically relevant conditions. Here in this paper, we show that ambient pressure X-ray photoelectron spectroscopy (APXPS) with a conventional X-ray source can be used to study the effects of water exposure on the interaction of a nanometer-thin polyacrylic acid (PAA) layer with a native aluminum oxide surface. The formation of a carboxylate ionic bond at the interface is characterized both with APXPS and in situ attenuated total reflectance Fourier transform infrared spectroscopy in themore » Kretschmann geometry (ATR-FTIR Kretschmann). When water is dosed in the APXPS chamber up to 5 Torr (~28% relative humidity), an increase in the amount of ionic bonds at the interface is observed. To confirm our APXPS interpretation, complementary ATR-FTIR Kretschmann experiments on a similar model system, which is exposed to an aqueous electrolyte, are conducted. These spectra demonstrate that water leads to an increased wet adhesion through increased ionic bond formation.« less

Exceptional cost effectiveness of the Solarcrete construction system with hybrid solar for McCormick's piano showroom

DOE Office of Scientific and Technical Information (OSTI.GOV)

Levy, M.T.

1980-01-01

A new building was designed to house Northeast Indiana's largest keyboard instrument showroom, offices, and warehouse. The 7653 SF building faces 8/sup 0/ east of south in a climate of 41/sup 0/ NL, 6717 DD, and 49% of possible sunshine during the heating season. The energy system may be described as hybrid using an integration of passive direct gain, water thermal storage with earth contact, evaporative cooling, and water source heat pump. The thermal envelope of the building employs the Solarcrete method devised to render improved thermal performance and reduce labor time, skill, and effort resulting in both initial andmore » life-cycle savings. The initial cost savings on the building including the tax credit of $11,076 was 33% or $79,076 LESS than a conventional building. The owners have realized 84% energy savings on the annual usage for the first year of operation.« less

Initiation of Martian Outflow Channels: Related to the Dissociation of Gas Hydrate?

NASA Technical Reports Server (NTRS)

Max, Michael D.; Clifford, Stephen M.

2001-01-01

We propose that the disruption of subpermafrost aquifers on Mars by the thermal- or pressure-induced dissociation of methane hydrate may have been a frequent trigger for initiating outflow channel activity. This possibility is raised by recent work that suggests that significant amounts of methane and gas hydrate may have been produced within and beneath the planet's cryosphere. On Earth, the build-up of overpressured water and gas by the decomposition of hydrate deposits has been implicated in the formation of large blowout features on the ocean floor. These features display a remarkable resemblance (in both morphology and scale) to the chaotic terrain found at the source of many Martian channels. The destabilization of hydrate can generate pressures sufficient to disrupt aquifers confined by up to 5 kilometers of frozen ground, while smaller discharges may result from the water produced by the decomposition of near-surface hydrate alone.

Implementation of CUAHSI-HIS Community Project Components in a Local Observatory

NASA Astrophysics Data System (ADS)

Muste, M.; Arnold, N.; Kim, D.

2008-12-01

The deployment of the eleven WATERS Network local observatories using CUAHSI-HIS project products showed that water observations data collected by academic investigators could be stored, published on the Internet, federated with water observations data published by water agencies, and searched using a concept framework that connects with variables in each individual data source. For many within the water resources community, the CUAHSI-HIS community project represents a new opportunity to approach the management, publication, and analysis of their data systematically - i.e., moving from collections of ASCII text or spreadsheet files to relational data models. This research describes the initial efforts carried out by a University of Iowa research group during the component implementation of a hydrologic community project in a local CI-based digital watershed (DW). The goal was to test what types of data query the DW can handle and see how it performs in use cases where data streams are coupled with models for continuous forecasting. This paper also discusses the general context for the DW development and summarizes the lessons learned by the group during this initial developmental stage. Given the uniform and scalable nature of the community project components, it is expected that the workflows presented herein are transferable to other users and other watersheds.

Experimental study on soluble chemical transfer to surface runoff from soil.

PubMed

Tong, Juxiu; Yang, Jinzhong; Hu, Bill X; Sun, Huaiwei

2016-10-01

Prevention of chemical transfer from soil to surface runoff, under condition of irrigation and subsurface drainage, would improve surface water quality. In this paper, a series of laboratory experiments were conducted to assess the effects of various soil and hydraulic factors on chemical transfer from soil to surface runoff. The factors include maximum depth of ponding water on soil surface, initial volumetric water content of soil, depth of soil with low porosity, type or texture of soil and condition of drainage. In the experiments, two soils, sand and loam, mixed with different quantities of soluble KCl were filled in the sandboxes and prepared under different initial saturated conditions. Simulated rainfall induced surface runoff are operated in the soils, and various ponding water depths on soil surface are simulated. Flow rates and KCl concentration of surface runoff are measured during the experiments. The following conclusions are made from the study results: (1) KCl concentration in surface runoff water would decrease with the increase of the maximum depth of ponding water on soil surface; (2) KCl concentration in surface runoff water would increase with the increase of initial volumetric water content in the soil; (3) smaller depth of soil with less porosity or deeper depth of soil with larger porosity leads to less KCl transfer to surface runoff; (4) the soil with finer texture, such as loam, could keep more fertilizer in soil, which will result in more KCl concentration in surface runoff; and (5) good subsurface drainage condition will increase the infiltration and drainage rates during rainfall event and will decrease KCl concentration in surface runoff. Therefore, it is necessary to reuse drained fertile water effectively during rainfall, without polluting groundwater. These study results should be considered in agriculture management to reduce soluble chemical transfer from soil to surface runoff for reducing non-point sources pollution.

Microbial water pollution: a screening tool for initial catchment-scale assessment and source apportionment.

PubMed

Kay, D; Anthony, S; Crowther, J; Chambers, B J; Nicholson, F A; Chadwick, D; Stapleton, C M; Wyer, M D

2010-11-01

The European Union Water Framework Directive requires that Management Plans are developed for individual River Basin Districts. From the point of view of faecal indicator organisms (FIOs), there is a critical need for screening tools that can provide a rapid assessment of the likely FIO concentrations and fluxes within catchments under base- and high-flow conditions, and of the balance ('source apportionment') between agriculture- and sewage-derived sources. Accordingly, the present paper reports on: (1) the development of preliminary generic models, using water quality and land cover data from previous UK catchment studies for assessing FIO concentrations, fluxes and source apportionment within catchments during the summer bathing season; (2) the calibration of national land use data, against data previously used in the models; and (3) provisional FIO concentration and source-apportionment assessments for England and Wales. The models clearly highlighted the crucial importance of high-flow conditions for the flux of FIOs within catchments. At high flow, improved grassland (and associated livestock) was the key FIO source; FIO loadings derived from catchments with high proportions of improved grassland were shown to be as high as from urbanized catchments; and in many rural catchments, especially in NW and SW England and Wales, which are important areas of lowland livestock (especially dairy) farming, ≥ 40% of FIOs was assessed to be derived from agricultural sources. In contrast, under base-flow conditions, when there was little or no runoff from agricultural land, urban (i.e. sewerage-related) sources were assessed to dominate, and even in rural areas the majority of FIOs were attributed to urban sources. The results of the study demonstrate the potential of this type of approach, particularly in light of climate change and the likelihood of more high-flow events, in underpinning informed policy development and prioritization of investment. Copyright © 2009 Elsevier B.V. All rights reserved.

Reducing epistemic errors in water quality modelling through high-frequency data and stakeholder collaboration: the case of an industrial spill

NASA Astrophysics Data System (ADS)

Krueger, Tobias; Inman, Alex; Paling, Nick

2014-05-01

Catchment management, as driven by legislation such as the EU WFD or grassroots initiatives, requires the apportionment of in-stream pollution to point and diffuse sources so that mitigation measures can be targeted and costs and benefits shared. Source apportionment is typically done via modelling. Given model imperfections and input data errors, it has become state-of-the-art to employ an uncertainty framework. However, what is not easily incorporated in such a framework, and currently much discussed in hydrology, are epistemic uncertainties, i.e. those uncertainties that relate to lack of knowledge about processes and data. For example, what if an otherwise negligible source suddenly matters because of an accidental pollution incident? In this paper we present such a case of epistemic error, an industrial spill ignored in a water quality model, demonstrate the bias of the resulting model simulations, and show how the error was discovered somewhat incidentally by auxiliary high-frequency data and finally corrected through the collective intelligence of a stakeholder network. We suggest that accidental pollution incidents like this are a wide-spread, though largely ignored, problem. Hence our discussion will reflect on the practice of catchment monitoring, modelling and management in general. The case itself occurred as part of ongoing modelling support in the Tamar catchment, one of the priority catchments of the UK government's new approach to managing water resources more decentralised and collaboratively. An Extended Export Coefficient Model (ECM+) had been developed with stakeholders to simulate transfers of nutrients (N & P), sediment and Faecal Coliforms from land to water and down the river network as a function of sewage treatment options, land use, livestock densities and farm management practices. In the process of updating the model for the hydrological years 2008-2012 an over-prediction of the annual average P concentration by the model was found at one sub-catchment outlet compared to high-frequency measurements at this point that had become available through another UK government initiative, the Demonstration Test Catchments. This discrepancy had gone unnoticed when calibrating the model in a probabilistic framework against the statutory monitoring data due to the high uncertainties associated with their low-frequency monitoring regime. According to these data what turned out to be an over-prediction seemed possible, albeit with low probability. It was only through the well-established contacts with the local stakeholders that this anomaly could be connected to an industrial spill elsewhere in the catchment, and the model eventually corrected for this additional source. Failing to account for this source would have resulted in drastic over-estimation of the contributions of other sources, in particular agriculture, and eventually wrong targeting of catchment restoration funds and collateral damage of stakeholder relations. The paper will conclude with a discussion of the following general points: the pretence of uncertainty frameworks in the light of epistemic errors; the value of high-frequency data; the value of stakeholder collaboration, particularly in the light of sharing sensitive information; the (somewhat incidental) synergies of various pieces of information and policy initiatives.

Major new sources of biological ice nuclei

NASA Astrophysics Data System (ADS)

Moffett, B. F.; Hill, T.; Henderson-Begg, S. K.

2009-12-01

Almost all research on biological ice nucleation has focussed on a limited number of bacteria. Here we characterise several major new sources of biogenic ice nuclei. These include mosses, hornworts, liverworts and cyanobacteria. Ice nucleation in the eukaryotic bryophytes appears to be ubiquitous. The temperature at which these organisms nucleate is that at which the difference in vapour pressure over ice and water is at or close to its maximum. At these temperatures (-8 to -18 degrees C) ice will grow at the expense of supercooled water. These organisms are dependent for their water on occult precipitation - fog, dew and cloudwater which by its nature is not collected in conventional rain gauges. Therefore we suggest that these organism produce ice nuclei as a water harvesting mechanism. Since the same mechanism would also drive the Bergeron-Findeisen process, and as moss is known to become airborne, these nuclei may have a role in the initiation of precipitation. The properties of these ice nuclei are very different from the well characterised bacterial nuclei. We will also present DNA sequence data showing that, although related, the proteins responsible are only very distantly related to the classical bacterial ice nuclei.

Will water scarcity in semiarid regions limit hydraulic fracturing of shale plays?

NASA Astrophysics Data System (ADS)

Scanlon, Bridget R.; Reedy, Robert C.; Nicot, Jean Philippe

2014-12-01

There is increasing concern about water constraints limiting oil and gas production using hydraulic fracturing (HF) in shale plays, particularly in semiarid regions and during droughts. Here we evaluate HF vulnerability by comparing HF water demand with supply in the semiarid Texas Eagle Ford play, the largest shale oil producer globally. Current HF water demand (18 billion gallons, bgal; 68 billion liters, bL in 2013) equates to ˜16% of total water consumption in the play area. Projected HF water demand of ˜330 bgal with ˜62 000 additional wells over the next 20 years equates to ˜10% of historic groundwater depletion from regional irrigation. Estimated potential freshwater supplies include ˜1000 bgal over 20 yr from recharge and ˜10 000 bgal from aquifer storage, with land-owner lease agreements often stipulating purchase of freshwater. However, pumpage has resulted in excessive drawdown locally with estimated declines of ˜100-200 ft in ˜6% of the western play area since HF began in 2009-2013. Non-freshwater sources include initial flowback water, which is ≤5% of HF water demand, limiting reuse/recycling. Operators report shifting to brackish groundwater with estimated groundwater storage of 80 000 bgal. Comparison with other semiarid plays indicates increasing brackish groundwater and produced water use in the Permian Basin and large surface water inputs from the Missouri River in the Bakken play. The variety of water sources in semiarid regions, with projected HF water demand representing ˜3% of fresh and ˜1% of brackish water storage in the Eagle Ford footprint indicates that, with appropriate management, water availability should not physically limit future shale energy production.

The impact of changes in source water quality on trihalomethane and haloacetonitrile formation in chlorinated drinking water.

PubMed

Xue, Chonghua; Wang, Qi; Chu, Wenhai; Templeton, Michael R

2014-12-01

This study examined the formation of disinfection by-products (DBPs), including nitrogenous DBPs, haloacetonitriles (HANs), and carbonaceous DBPs, trihalomethanes (THMs), upon chlorination of water samples collected from a conventional Chinese surface water treatment plant (i.e. applying coagulation, sedimentation, and filtration). Reductions in the average concentrations (and range, shown in brackets) of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) from 4.8 (3.0-7.3) μg/L and 0.52 (0.20-0.81) μg/L in 2010 to 2.4 (1.4-3.7) μg/L and 0.17 (0.11-0.31) μg/L in 2012, respectively, led to a decrease in HANs and THMs from 5.3 and 28.5 μg/L initially to 0.85 and 8.2 μg/L, as average concentrations, respectively. The bromide concentration in the source water also decreased from 2010 to 2012, but the bromine incorporation factor (BIF) for the THMs did not change significantly; however, for HAN the BIFs increased because the reduction in DON was higher than that of bromide. There was good linear relationship between DOC and THM concentrations, but not between DON and HANs. Copyright © 2014 Elsevier Ltd. All rights reserved.

MERCURY MEASUREMENTS USING DIRECT-ANALYZER ...

EPA Pesticide Factsheets

Under EPA's Water Quality Research Program, exposure studies are needed to determine how well control strategies and guidance are working. Consequently, reliable and convenient techniques that minimize waste production are of special interest. While traditional methods for determining mercury in solid samples involve the use of aggressive chemicals to dissolve the matrix and the use of other chemicals to properly reduce the mercury to the volatile elemental form, pyrolysis-based analyzers can be used by directly weighing the solid in a sampling boat and initiating the instrumental analysis for total mercury. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are the various research projects being performed in support of this Task and more in-depth coverage of each project. Briefly, each project's objective is stated below.Subtask 1: To integrate state-of-the-art technologies (polar organic chemical integrative samplers, advanced solid-phase extraction methodologies with liquid chromatography/electrospray/mass spectrometry) and apply them to studying the sources and fate of a select list of PPCPs. Application and improvement of analytical methodologies that can detect non-volatile, polar, water-soluble pharmaceuticals in source waters at levels that could be environmentally significant (at con

Effect of Chlorella sorokiniana on the biological denitrification of drinking water.

PubMed

Petrovič, Aleksandra; Simonič, Marjana

2015-04-01

The influence of Chlorella sorokiniana on drinking water's biological denitrification was studied at two different initial nitrate concentrations, 50 and 100 mg/L, respectively. Sucrose and grape juice were used as carbon sources. The experiments showed that the denitrification process in the presence of algae was, even at low concentrations, i.e. 50 mg/L of nitrate, slower than without them, but yet still more than 95% of nitrate was removed in 24 h. It was also discovered that, with the addition of ammonium and urea, the urea interfered much more with the denitrification process, as less than 50% of the initial nitrate was removed. However, algae did not contribute to the nitrate and ammonium removals, as the final concentrations of both in the presence of algae were higher by approx 5%. At 100 mg/L of initial nitrate, the denitrification kinetics in the presence of algae was apparently slower regarding those experiments at lower levels of nitrate and only 65-70% of nitrate was removed over 24 h. Using grape juice instead of sucrose improved the nitrate removal slightly.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edwards, P.L.

As the Oct. 31 deadline for an initial design review approaches, the four participants in the Energy Research and Development Administration's (ERDA) industrial process hot water program are putting the final touches to plans for solar systems that will supplement conventional energy sources in the textile, food processing, concrete block and cleaning industries. Participating in the project are AAI Corp., Baltimore, which designed a solar hot water system for the concrete block curing operation of York Building Products Co., Harrisburg, Pa.; Acurex Corp., Mountain View, Calif., which designed a solar hot water system for a can washing line at themore » Campbell Soup Co. plant in Sacramento, Calif.; General Electric Co., Philadelphia, which designed a solar hot water system for Riegel Textile Corp., La France, S.C.; and Jacobs Engineering Co., Pasadena, Calif., which designed a solar hot water and steam system for commercial laundry use at American Linen Supply in El Centro., Calif. (MCW)« less

Development of Techniques to Investigate Sonoluminescence as a Source of Energy Harvesting

NASA Technical Reports Server (NTRS)

Wrbanek, John D.; Fralick, Gustave C.; Wrbanek, Susan Y.

2007-01-01

Instrumentation techniques are being developed at NASA Glenn Research Center to measure optical, radiation, and thermal properties of the phenomena of sonoluminescence, the light generated using acoustic cavitation. Initial efforts have been directed to the generation of the effect and the imaging of the glow in water and solvents. Several images have been produced of the effect showing the location within containers, without the additions of light enhancers to the liquid. Evidence of high energy generation in the modification of thin films from sonoluminescence in heavy water was seen that was not seen in light water. Bright, localized sonoluminescence was generated using glycerin for possible applications to energy harvesting. Issues to be resolved for an energy harvesting concept will be addressed.

Numerical demonstration of surfactant concentration-dependent capillarity and viscosity effects on infiltration from a constant flux line source

NASA Astrophysics Data System (ADS)

Henry, Eric J.; Smith, James E.

2006-09-01

SummarySurface infiltration line sources can deliver surfactant solutions for agricultural purposes or for use in subsurface remediation. Though the prediction of water distribution below a line source has received considerable attention in the scientific literature, little has been has been reported on how infiltration of surfactant solution from a line source differs from water infiltration. Few numerical models are capable of simulating surfactant-induced changes in moisture characteristic and hydraulic conductivity properties of unsaturated soil, so it is difficult to assess the importance of these effects when designing surfactant application schemes. We investigated surfactant infiltration behavior by using the variably-saturated flow and transport model HYDRUS-2D [Simunek, J., Sejna, M., van Genuchten, M.Th., 1999. The HYDRUS-2D software package for simulating the two-dimensional movement of water, heat, and multiple solutes in variably-saturated media, Version 2.0. IGWMC-TPS-53C. International Ground Water Modeling Center, Colorado School of Mines, Golden, CO] which was modified by [Henry, E.J., Smith, J.E., Warrick, A.W., 2002. Two-dimensional modeling of flow and transport in the vadose zone with surfactant-induced flow. Water Resour. Res. 38. DOI: doi:10.1029/2001WR000674] to incorporate surfactant effects on unsaturated flow. Significant differences were found between pure water and surfactant solution infiltration into a fine sand that was initially at residual moisture content. The surfactant solution wetted a larger area, both horizontally and vertically, relative to water, while the distribution of water within the wetted zone was more uniform than in the surfactant system. The surfactant system exhibited transient localized drainage and rewetting caused by surfactant-induced capillary pressure gradients within the wetting front. A standard unsaturated flow model (i.e., one that does not include surfactant effects on flow) is not capable of capturing the transient flow behavior. However, our results show that by using an effective scaled media (ESM) approach a standard model can be used to simulate later-time hydraulic conditions in a surfactant system.

Bacterial source tracking guides management of boat head waste in a coastal resort area.

PubMed

Mallin, Michael A; Haltom, Mary I; Song, Bongkeun; Tavares, Mary E; Dellies, Stephen P

2010-12-01

Fecal contamination of water bodies causes a public health problem and economic loss. To control such contamination management actions need to be guided by sound science. From 2007-2009 a study was undertaken to determine the sources of fecal bacteria contamination to the marine waters adjoining the Town of Wrightsville Beach, North Carolina, USA. The research effort included sampling for fecal coliform and Enterococcus bacteria, sampling for optical brighteners, dye studies, and use of molecular bacterial source tracking techniques including polymerase chain reaction (PCR) and terminal restriction fragment polymorphism (T-RFLP) fingerprinting of the Bacteroides-Prevotella group. Of the 96 samples collected from nine locations during the study, the water contact standard for Enterococcus was exceeded on 13 occasions. The T-RFLP fingerprint analyses demonstrated that the most widespread source of fecal contamination was human, occurring in 38% of the samples, with secondary ruminant and avian sources also detected. Optical brightener concentrations were low, reflecting a lack of sewage line leakage or spills. A lack of sewer leaks and lack of septic systems in the town pointed toward discharge from boat heads into the marine waters as the major cause of fecal contamination; this was supported by dye studies. Based on these data, the Town initiated action to have the U.S. Environmental Protection Agency declare the coastal waters (out to 3 nautical miles), the nearby Atlantic Intracoastal Waterway and its tributaries a no-discharge zone (NDZ) to alleviate the human fecal pollution. The Town garnered supporting resolutions from other local communities who jointly petitioned the North Carolina Department of Environmental and Natural Resources. This State regulatory agency supported the local government resolutions and sent an application for an NDZ to the EPA in April 2009. The EPA concurred, and in February 2010 the coastal waters of New Hanover County, NC, became the first marine area on the U.S. eastern seaboard between Delaware and the Florida Keys to be declared a no-discharge zone. Copyright © 2010 Elsevier Ltd. All rights reserved.

Water, energy, and biogeochemical budgets investigation at Panola Mountain research watershed, Stockbridge, Georgia; a research plan

USGS Publications Warehouse

Huntington, T.G.; Hooper, R.P.; Peters, N.E.; Bullen, T.D.; Kendall, Carol

1993-01-01

The Panola Mountain Research Watershed (PMRW), located in the Panola Mountain State Conservation Park near Stockbridge, Georgia has been selected as a core research watershed under the Water, Energy and Biogeochemical Budgets (WEBB) research initiative of the U.S. Geological Survey (USGS) Global Climate Change Program. This research plan describes ongoing and planned research activities at PMRW from 1984 to 1994. Since 1984, PMRW has been studied as a geochemical process research site under the U.S. Acid Precipitation Thrust Program. Research conducted under this Thrust Program focused on the estimation of dry atmospheric deposition, short-term temporal variability of streamwater chemistry, sulfate adsorption characteristics of the soils, groundwater chemistry, throughfall chemistry, and streamwater quality. The Acid Precipitation Thrust Program continues (1993) to support data collection and a water-quality laboratory. Proposed research to be supported by the WEBB program is organized in 3 interrelated categories: streamflow generation and water-quality evolution, weathering and geochemical evolution, and regulation of soil-water chemistry. Proposed research on streamflow generation and water-quality evolution will focus on subsurface water movement, its influence in streamflow generation, and the associated chemical changes of the water that take place along its flowpath. Proposed research on weathering and geochemical evolution will identify the sources of cations observed in the streamwater at Panola Mountain and quantify the changes in cation source during storms. Proposed research on regulation of soil-water chemistry will focus on the poorly understood processes that regulate soil-water and groundwater chemistry. (USGS)

Development of Vertical Cable Seismic System (3)

NASA Astrophysics Data System (ADS)

Asakawa, E.; Murakami, F.; Tsukahara, H.; Mizohata, S.; Ishikawa, K.

2013-12-01

The VCS (Vertical Cable Seismic) is one of the reflection seismic methods. It uses hydrophone arrays vertically moored from the seafloor to record acoustic waves generated by surface, deep-towed or ocean bottom sources. Analyzing the reflections from the sub-seabed, we could look into the subsurface structure. Because VCS is an efficient high-resolution 3D seismic survey method for a spatially-bounded area, we proposed the method for the hydrothermal deposit survey tool development program that the Ministry of Education, Culture, Sports, Science and Technology (MEXT) started in 2009. We are now developing a VCS system, including not only data acquisition hardware but data processing and analysis technique. We carried out several VCS surveys combining with surface towed source, deep towed source and ocean bottom source. The water depths of the survey are from 100m up to 2100m. The target of the survey includes not only hydrothermal deposit but oil and gas exploration. Through these experiments, our VCS data acquisition system has been completed. But the data processing techniques are still on the way. One of the most critical issues is the positioning in the water. The uncertainty in the positions of the source and of the hydrophones in water degraded the quality of subsurface image. GPS navigation system are available on sea surface, but in case of deep-towed source or ocean bottom source, the accuracy of shot position with SSBL/USBL is not sufficient for the very high-resolution imaging. We have developed another approach to determine the positions in water using the travel time data from the source to VCS hydrophones. In the data acquisition stage, we estimate the position of VCS location with slant ranging method from the sea surface. The deep-towed source or ocean bottom source is estimated by SSBL/USBL. The water velocity profile is measured by XCTD. After the data acquisition, we pick the first break times of the VCS recorded data. The estimated positions of shot points and receiver points in the field include the errors. We use these data as initial guesses, we invert iteratively shot and receiver positions to match the travel time data. After several iterations we could finally estimate the most probable positions. Integration of the constraint of VCS hydrophone positions, such as the spacing is 10m, can accelerate the convergence of the iterative inversion and improve results. The accuracy of the estimated positions from the travel time date is enough for the VCS data processing.

Identifying sources of stream water sulfate after a summer drought in the Sleepers River watershed (Vermont, USA) using hydrological, chemical, and isotopic techniques

USGS Publications Warehouse

Mayer, B.; Shanley, J.B.; Bailey, S.W.; Mitchell, M.J.

2010-01-01

In many forested headwater catchments, peak SO42 - concentrations in stream water occur in the late summer or fall following drought potentially resulting in episodic stream acidification. The sources of highly elevated stream water SO42 - concentrations were investigated in a first order stream at the Sleepers River watershed (Vermont, USA) after the particularly dry summer of 2001 using a combination of hydrological, chemical and isotopic approaches. Throughout the summer of 2001 SO42 - concentrations in stream water doubled from ???130 to 270 ??eq/L while flows decreased. Simultaneously increasing Na+ and Ca2+ concentrations and ??34S values increasing from +7??? towards those of bedrock S (???+10.5???) indicated that chemical weathering involving hydrolysis of silicates and oxidation of sulfide minerals in schists and phyllites was the cause for the initial increase in SO42 - concentrations. During re-wetting of the watershed in late September and early October of 2001, increasing stream flows were accompanied by decreasing Na+ and Ca2+ concentrations, but SO42 - concentrations continued to increase up to 568 ??eq/L, indicating that a major source of SO42 - in addition to bedrock weathering contributed to peak SO42 - concentrations. The further increase in SO42 - concentrations coincided with an abrupt decrease of ??34S values in stream water SO42 - from maximum values near +10??? to minimum values near -3???. Soil investigations revealed that some C-horizons in the Spodsols of the watershed contained secondary sulfide minerals with ??34S values near -22???. The shift to negative ??34S values of stream water SO42 - indicates that secondary sulfides in C-horizons were oxidized to SO42 - during the particularly dry summer of 2001. The newly formed SO42 - was transported to the streams during re-wetting of the watershed contributing ???60% of the SO42 - during peak concentrations in the stream water. Thereafter, the contribution of SO42 - from oxidation of secondary sulfides in C-horizons decreased rapidly and pedogenic SO42 - reemerged as a dominant SO42 - source in concert with decreasing SO42 - concentrations in spring of 2002. The study provides evidence that a quantitative assessment of the sources of stream water SO42 - in forested watersheds is possible by combining hydrological, chemical and isotopic techniques, provided that the isotopic compositions of all potential SO42 - sources are distinctly different. ?? 2010 Elsevier Ltd.

Closing the water cycle - the key role of water and wastewater management in a circular economy

NASA Astrophysics Data System (ADS)

Uhlenbrook, Stefan; Connor, Rick; Koncagul, Engin; Ortigara, Angela

2017-04-01

Planetary water boundaries are exceeded locally and regionally as water demand and use are escalating and per capita water availability is decreasing. However, wastewater represents an alternative yet reliable source containing for instance, nutrients (for use as fertilizer) and metals that can be extracted, and can be a source of energy. These characteristics mean that water and wastewater are set to play a key role in the circular economy. Furthermore, wastewater use can generate business opportunities and enhance water, food and energy security, therefore helping to alleviate poverty. However, to increase the collection, treatment and use of wastewater, investments in infrastructure and appropriate (low cost) technologies are needed. Ensuring the development of human and institutional capacity is also essential for proper wastewater management. The UN World Water Assessment Programme (WWAP) produces together with several UN-Water Members and Partners the annual World Water Development Report (WWDR). Its 2017 edition "Wastewater: The Untapped Resource" focuses on the critical role of wastewater management for vibrant economies, resilient societies and the maintenance of a healthy environment. Wastewater issues play also a central role in the 2030 Agenda for Sustainable Development, most notably through Sustainable Development Goal (SDG) target 6.3 that aims to improve water quality by reducing the proportion of untreated wastewater released to the environment and increasing its recycling and safe reuse globally. This target is interlinked with several other targets of SDG 6 ('the water goal') as well as to several other SDGs that relate to, poverty reduction, health, energy and food security, among others. The main policy-relevant messages of the WWDR 2017 will be introduced and linked to socio-hydrological approaches. These messages are an important input to the implementation of the water research agenda of the Panta Rhei initiative of IAHS.

Development and evaluation of a culture-independent method for source determination of fecal wastes in surface and storm waters using reverse transcriptase-PCR detection of FRNA coliphage genogroup gene sequences.

PubMed

Paar, Jack; Doolittle, Mark M; Varma, Manju; Siefring, Shawn; Oshima, Kevin; Haugland, Richard A

2015-05-01

A method, incorporating recently improved reverse transcriptase-PCR primer/probe assays and including controls for detecting interferences in RNA recovery and analysis, was developed for the direct, culture-independent detection of genetic markers from FRNA coliphage genogroups I, II & IV in water samples. Results were obtained from an initial evaluation of the performance of this method in analyses of waste water, ambient surface water and stormwater drain and outfall samples from predominantly urban locations. The evaluation also included a comparison of the occurrence of the FRNA genetic markers with genetic markers from general and human-related bacterial fecal indicators determined by current or pending EPA-validated qPCR methods. Strong associations were observed between the occurrence of the putatively human related FRNA genogroup II marker and the densities of the bacterial markers in the stormwater drain and outfall samples. However fewer samples were positive for FRNA coliphage compared to either the general bacterial fecal indicator or the human-related bacterial fecal indicator markers particularly for ambient water samples. Together, these methods show promise as complementary tools for the identification of contaminated storm water drainage systems as well as the determination of human and non-human sources of contamination. Published by Elsevier B.V.

Using low-cost drones to map malaria vector habitats.

PubMed

Hardy, Andy; Makame, Makame; Cross, Dónall; Majambere, Silas; Msellem, Mwinyi

2017-01-14

There is a growing awareness that if we are to achieve the ambitious goal of malaria elimination, we must compliment indoor-based vector control interventions (such as bednets and indoor spraying) with outdoor-based interventions such as larval source management (LSM). The effectiveness of LSM is limited by our capacity to identify and map mosquito aquatic habitats. This study provides a proof of concept for the use of a low-cost (< $1000) drone (DJI Phantom) for mapping water bodies in seven sites across Zanzibar including natural water bodies, irrigated and non-irrigated rice paddies, peri-urban and urban locations. With flying times of less than 30 min for each site, high-resolution (7 cm) georeferenced images were successfully generated for each of the seven sites, covering areas up to 30 ha. Water bodies were readily identifiable in the imagery, as well as ancillary information for planning LSM activities (access routes to water bodies by road and foot) and public health management (e.g. identification of drinking water sources, mapping individual households and the nature of their construction). The drone-based surveys carried out in this study provide a low-cost and flexible solution to mapping water bodies for operational dissemination of LSM initiatives in mosquito vector-borne disease elimination campaigns. Generated orthomosaics can also be used to provide vital information for other public health planning activities.

Case Study for the ARRA-funded Ground Source Heat Pump Demonstration at Denver Museum of Nature & Science

DOE Office of Scientific and Technical Information (OSTI.GOV)

Im, Piljae; Liu, Xiaobing

High initial costs and lack of public awareness of ground-source heat pump (GSHP) technology are the two major barriers preventing rapid deployment of this energy-saving technology in the United States. Under the American Recovery and Reinvestment Act (ARRA), 26 GSHP projects were competitively selected and carried out to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. This report highlights the findings of a case study of one such GSHP demonstration projects that uses a recycled water heat pump (RWHP) system installed at the Denver Museum of Nature & Science in Denver, Colorado. Themore » RWHP system uses recycled water from the city’s water system as the heat sink and source for a modular water-to-water heat pump (WWHP). This case study was conducted based on the available measured performance data from December 2014 through August 2015, utility bills of the building in 2014 and 2015, construction drawings, maintenance records, personal communications, and construction costs. The annual energy consumption of the RWHP system was calculated based on the available measured data and other related information. It was compared with the performance of a baseline scenario— a conventional VAV system using a water-cooled chiller and a natural gas fired boiler, both of which have the minimum energy efficiencies allowed by ASHRAE 90.1-2010. The comparison was made to determine energy savings, operating cost savings, and CO2 emission reductions achieved by the RWHP system. A cost analysis was performed to evaluate the simple payback of the RWHP system. Summarized below are the results of the performance analysis, the learned lessons, and recommended improvement in the operation of the RWHP system.« less

Changes in water quality in agricultural catchments after deployment of wastewater treatment plant.

PubMed

Langhammer, Jakub; Rödlová, Sylva

2013-12-01

Insufficient wastewater remediation in small communities and nonpoint source pollution are the key factors in determining the water quality of small streams in an agricultural landscape. Despite the current extensive construction of municipal wastewater treatment facilities in small communities, the level of organic substances and nutrients in the recipient catchments has not decreased in many areas. This paper analyzes the changes in the water quality of the small streams after the deployment of wastewater treatment plants that were designed to address sources of pollution from small municipalities. The analysis is based on the results from a water quality monitoring network in the small watersheds in the Czech Republic. Five rural catchments with one dominant municipal pollution source, where a wastewater treatment plant was deployed during the monitoring period, were selected according to a predefined set of criteria, from a series of 317 profiles. Basic water quality indicators were selected for the assessment: O₂, BOD-5, COD, TOC, conductivity, NH₄-N, NO₂-N, NO₃-N, PT, and PO₄-P. Results of the analysis showed that the simple deployment of the water treatment facilities at these streams often did not lead to a reduction of contamination in the streams. The expected post-deployment changes, namely, a significant and permanent reduction of stream contamination, occurred only in one catchment, whereas in the remainder of the catchments, only marginal changes or even increased concentrations of the contaminants were detected. As the critical factors that determined the efficiency of wastewater treatment were studied, the need for the consideration of the local conditions during the design of the facility, particularly regarding the size of the catchments, initial level of contamination, proper system of operation, and process optimization of the treatment facility, emerged as the important factor.

Assessing the Nation's Brackish Groundwater Resources

NASA Astrophysics Data System (ADS)

Stanton, J.; Anning, D. W.; Moore, R. B.; McMahon, P. B.; Bohlke, J. K.; McGuire, V. L.

2014-12-01

Declines in the amount of groundwater in storage as a result of groundwater development have led to concerns about the future availability of freshwater to meet drinking-water, agricultural, industrial, and environmental needs. Industry and public drinking-water suppliers have increasingly turned to nontraditional groundwater sources, such as moderately saline (brackish) groundwater, to supplement or replace the use of freshwater. Despite the growing demand for alternative water sources, a significant potential nontraditional water resource, brackish groundwater, was last assessed almost 50 years ago. The recently (2013) initiated USGS National Brackish Groundwater Assessment, which is part of the National Water Census, will provide an updated systematic national assessment of the distribution of significant brackish groundwater resources and critical information about the hydrogeologic and chemical characterization of brackish aquifers. As part of this study, updated national-scale maps of total dissolved-solids concentrations and chemical water types will be created using data from about 400,000 sites that have been compiled from over 30 national, regional, and state sources. However, available data are biased toward freshwater and shallow systems. Preliminary analysis indicates that about 75 percent of the dissolved-solids concentrations are from freshwater aquifers, and more than 80 percent represent depths less than 500 feet below land surface. Several techniques are used to extend the information contained in the compiled data. For about half of the sites, dissolved-solids concentration was estimated from specific conductance using statistical relations. In addition, for areas where chemical data are not available, regression models are being developed to predict the occurrence of brackish groundwater based on geospatial data such as geology and other variables that are correlated to dissolved-solids concentrations.

Chemical and physical characterization of produced waters from conventional and unconventional fossil fuel resources.

PubMed

Alley, Bethany; Beebe, Alex; Rodgers, John; Castle, James W

2011-09-01

Characterization of produced waters (PWs) is an initial step for determining potential beneficial uses such as irrigation and surface water discharge at some sites. A meta-analysis of characteristics of five PW sources [i.e. shale gas (SGPWs), conventional natural gas (NGPWs), conventional oil (OPWs), coal-bed methane (CBMPWs), tight gas sands (TGSPWs)] was conducted from peer-reviewed literature, government or industry documents, book chapters, internet sources, analytical records from industry, and analyses of PW samples. This meta-analysis assembled a large dataset to extract information of interest such as differences and similarities in constituent and constituent concentrations across these sources of PWs. The PW data analyzed were comprised of 377 coal-bed methane, 165 oilfield, 137 tight gas sand, 4000 natural gas, and 541 shale gas records. Majority of SGPWs, NGPWs, OPWs, and TGSPWs contain chloride concentrations ranging from saline (>30000 mg L(-1)) to hypersaline (>40000 mg L(-1)), while most CBMPWs were fresh (<5000 mg L(-1)). For inorganic constituents, most SGPW and NGPW iron concentrations exceeded the numeric criterion for irrigation and surface water discharge, while OPW and CBMPW iron concentrations were less than the criterion. Approximately one-fourth of the PW samples in this database are fresh and likely need minimal treatment for metal and metalloid constituents prior to use, while some PWs are brackish (5000-30000 mg Cl(-) L(-1)) to saline containing metals and metalloids that may require considerable treatment. Other PWs are hypersaline and produce a considerable waste stream from reverse osmosis; remediation of these waters may not be feasible. After renovation, fresh to saline PWs may be used for irrigation and replenishing surface waters. Copyright © 2011 Elsevier Ltd. All rights reserved.

Risk assessment and source identification of perfluoroalkyl acids in surface and ground water: Spatial distribution around a mega-fluorochemical industrial park, China.

PubMed

Liu, Zhaoyang; Lu, Yonglong; Wang, Tieyu; Wang, Pei; Li, Qifeng; Johnson, Andrew C; Sarvajayakesavalu, Suriyanarayanan; Sweetman, Andrew J

2016-05-01

Perfluoroalkyl acids (PFAAs) can be released to water bodies during manufacturing and application of PFAA-containing products. In this study, the contamination pattern, attenuation dynamics, sources, pathways, and risk zoning of PFAAs in surface and ground water was examined within a 10km radius from a mega-fluorochemical industrial park (FIP). Among 12 detected PFAAs, perfluorooctanoic acid (PFOA) dominated, followed by shorter-chained perfluoroalkyl carboxylic acids (PFCAs). PFAA-containing waste was discharged from the FIP, with levels reaching 1.86mg/L in the nearby rivers flowing to the Bohai sea together with up to 273μg/L in the local groundwater in the catchment. These levels constitute a human health risks for PFOA and other shorter-chained PFCAs within this location. The concentrations of ∑PFAAs in surface water strongly correlated with the local groundwater. The dominant pollution pathways of PFAAs included (i) discharge into surface water then to groundwater through seepage, and (ii) atmospheric deposition from the FIP, followed by infiltration to groundwater. As the distance increased from the source, PFAAs levels in groundwater showed a sharp initial decrease followed by a gentle decline. The contamination signal from the FIP site on PFAAs in groundwater existed within a radius of 4km, and at least 3km from the polluted Dongzhulong River. The major controlling factor in PFAA attenuation processes was likely to be dilution together with dispersion and adsorption to aquifer solids. The relative abundance of PFOA (C8) declined while those of shorter-chained PFCAs (C4-C6) increased during surface water seepage and further dispersion in groundwater. Copyright © 2016 Elsevier Ltd. All rights reserved.

Field Scale Testing of RESOLVE at 2010 ISRU Analog Test

NASA Technical Reports Server (NTRS)

Captain, Janine E.; Quinn, J. W.; Moss, T. J.; Weis, K. H.

2010-01-01

When mankind returns to the moon, there will be one aspect of the architecture that will totally change how we explore the solar system. For the first time in space exploration, we will take the initial steps towards breaking our reliance on Earth-supplied consumables by extracting resources from planetary bodies. Our first efforts in this area, known as In Situ Resource Utilization (ISRU), will be directed at extracting some of the abundant oxygen found in the lunar regolith. But the "holy grail" of lunar ISRU will be finding an exploitable source of lunar hydrogen. If we can find a source of hydrogen that can be reasonably extracted from the regolith, it would provide a foundation for true independence from Earth consumables. With in-situ hydrogen and oxygen (and/or water) we can produce many of the major consumables needed to travel to and operate on a sustainable lunar outpost. We would have water to drink, oxygen to breath, and rocket propellants and fuel cell reagents to enable extended access and operations across the moon. NASA initiated development of an experiment package named RESOLVE (Regolith & Environment Science and Oxygen & Lunar Volatile Extraction) that could be flown to the rim or into a permanently shadowed crater to answer the questions surrounding elevated hydrogen at the lunar poles.

Dextrose monohydrate as a non-animal sourced alternative diluent in high shear wet granulation tablet formulations.

PubMed

Mitra, Biplob; Wolfe, Chad; Wu, Sy-Juen

2018-05-01

The feasibility of dextrose monohydrate as a non-animal sourced diluent in high shear wet granulation (HSWG) tablet formulations was determined. Impacts of granulation solution amount and addition time, wet massing time, impeller speed, powder and solution binder, and dry milling speed and screen opening size on granule size, friability and density, and tablet solid fraction (SF) and tensile strength (TS) were evaluated. The stability of theophylline tablets TS, disintegration time (DT) and in vitro dissolution were also studied. Following post-granulation drying at 60 °C, dextrose monohydrate lost 9% water and converted into the anhydrate form. Higher granulation solution amounts and faster addition, faster impeller speeds, and solution binder produced larger, denser and stronger (less friable) granules. All granules were compressed into tablets with acceptable TS. Contrary to what is normally observed, denser and larger granules (at ≥21% water level) produced tablets with a higher TS. The TS of the weakest tablets increased the most after storage at both 25 °C/60% RH and 40 °C/75% RH. Tablet DT was higher for stronger granules and after storage. Tablet dissolution profiles for 21% or less water were comparable and did not change on stability. However, the dissolution profile for tablets prepared with 24% water was slower initially and continued to decrease on stability. The results indicate a granulation water amount of not more than 21% is required to achieve acceptable tablet properties. This study clearly demonstrated the utility of dextrose monohydrate as a non-animal sourced diluent in a HSWG tablet formulation.

An impact-induced terrestrial atmosphere and iron-water reactions during accretion of the Earth

NASA Technical Reports Server (NTRS)

Lange, M. A.; Ahrens, T. J.

1985-01-01

Shock wave data and theoretical calculations were used to derive models of an impact-generated terrestrial atmosphere during accretion of the Earth. The models showed that impacts of infalling planetesimals not only provided the entire budget of terrestrial water but also led to a continuous depletion of near-surface layers of water-bearing minerals of their structural water. This resulted in a final atmospheric water reservoir comparable to the present day total water budget of the Earth. The interaction of metallic iron with free water at the surface of the accreting Earth is considered. We carried out model calcualtions simulating these processes during accretion. It is assumed that these processes are the prime source of the terrestrial FeO component of silicates and oxides. It is demonstrated that the iron-water reaction would result in the absence of atmospheric/hydrospheric water, if homogeneous accretion is assumed. In order to obtain the necessary amount of terrestrial water, slightly heterogeneous accretion with initially 36 wt% iron planetesimals, as compared with a homogeneous value of 34 wt% is required.

Preconditions for market solution to urban water scarcity: Empirical results from Hyderabad City, India

NASA Astrophysics Data System (ADS)

Saleth, R. Maria; Dinar, Ariel

2001-01-01

Utilizing both primary and secondary information pertaining to the water sector of Hyderabad City, India, this paper (1) evaluates the economics of various technically feasible supply augmentations options; (2) estimates the group-specific water demand and consumption response functions under alternative pricing behaviors; (3) calculates the net willingness to pay (NWTP, considered to be the value of raw water at source) of different user groups as derived from their respective price elasticities; (4) shows how inadequate the NWTP is to justify most supply augmentation options including intersectoral water transfers under the existing water rate structure; (5) argues that the economic and institutional conditions internal to urban water sector cannot justify an externally imposed water transfers, whether market-based or otherwise, as long as the water rate structure is inefficient and regressive; and (6) concludes by underlining the central role that the pricing option, both the level and structure, plays not only in activating a number of nonprice options but also in generating incentives for the emergence of new and the consolidation of existing institutional conditions needed to support economically rooted water transfers and conservation initiatives.

Suspended particle dynamics and fluxes in an Arctic fjord (Kongsfjorden, Svalbard)

NASA Astrophysics Data System (ADS)

Meslard, Florian; Bourrin, François; Many, Gaël; Kerhervé, Philippe

2018-05-01

An experiment was carried out during summer 2015 in the inner part of the Kongsfjorden to study the inputs of meltwater and behaviour of associated suspended particles. We used a wide range of oceanographic instruments to assess the hydrological and hydrodynamic characteristics of coastal waters. The transfer of suspended particles occurs from a large surface plume fed by two main sources: the most important one is the upwelling of fresh and turbid water coming from a tide-water glacier: the Kronebreen, and the second one from a continental glacier: the Kongsvegen. We estimated that these two sources discharged about 2.48 ± 0.37 × 106 t of suspended sediments during the two months of melting. The major part of these sediments is deposited within the first kilometre due to flocculation phenomena. Flocculation is initiated below the surface turbid plume and is mainly caused by the salinity gradient and high suspended particle concentration. Finally, our estimates of suspended particle fluxes by a typical Arctic coastal glacier showed the need to consider suspended sediment fluxes from high-latitude areas into global budgets in the context of climate change.

Hydrologic analysis of the Rio Grande Basin north of Embudo, New Mexico; Colorado and New Mexico

USGS Publications Warehouse

Hearne, G.A.; Dewey, J.D.

1988-01-01

Water yield was estimated for each of the five regions that represent contrasting hydrologic regimes in the 10,400 square miles of the Rio Grande basin above Embudo, New Mexico. Water yield was estimated as 2,800 cubic feet per second for the San Juan Mountains, and 28 cubic feet per second for the Taos Plateau. Evapotranspiration exceeded precipitation by 150 cubic feet per second on the Costilla Plains and 2,400 cubic feet per second on the Alamosa Basin. A three-dimensional model was constructed to represent the aquifer system in the Alamosa Basin. A preliminary analysis concluded that: (1) a seven-layer model representing 3,200 feet of saturated thickness could accurately simulate the behavior of the flow equation; and (2) the 1950 condition was approximately stable and would be a satisfactory initial condition. Reasonable modifications to groundwater withdrawals simulated 1950-79 water-level declines close to measured value. Sensitivity tests indicated that evapotranspiration salvage was the major source, 69 to 82 percent, of groundwater withdrawals. Evapotranspiration salvage was projected to be the source of most withdrawals. (USGS)

Natural and mining-related sources of dissolved minerals during low flow in the Upper Animas River Basin, southwestern Colorado

USGS Publications Warehouse

Wright, Winfield G.

1997-01-01

As part of the Clean Water Act of 1972 (Public Law 92-500), all States are required to establish water-quality standards for every river basin in the State. During 1994, the Colorado Department of Public Health and Environment proposed to the Colorado Water Quality Control Commission (CWQCC) an aquatic-life standard of 225 µg/L (micrograms per liter) for the dissolved-zinc concentration in the Animas River downstream from Silverton (fig.1). The CWQCC delayed implementation of this water-quality standard until further information was collected and a plan for the cleanup of abandoned mines was developed. Dissolved-zinc concentrations in this section of the river ranged from about 270 µg/L during high flow, when rainfall and snowmelt runoff dilute the dissolved minerals in the river (U.S. Geological Survey, 1996, p. 431), to 960 µg/L (Colorado Department of Public Health and Environment, written commun., 1996) during low flow (such as late summer and middle winter when natural springs and drainage from mines are the main sources for the streams). Mining sites in the basin were developed between about 1872 and the 1940's, with only a few mines operated until the early 1990's. For local governments, mining sites represent part of the Nation's heritage, tourists are attracted to the historic mining sites, and governments are obligated to protect the historic mining sites according to the National Historic Preservation Act (Public Law 89-665). In the context of this fact sheet, the term "natural sources of dissolved minerals" refers to springs and streams where no effect from mining were determined. "Mining-related sources of dissolved minerals" are assumed to be: (1 ) Water draining from mines , and (2) water seeping from mine-waste dump pile where the waste piles were saturated by water draining from mines. Although rainfall and snowmelt runoff from mine-waste piles might affect water quality in streams, work described in this fact sheet was done during low-flow conditions when springs and drainage from mine were the main sources of dissolved minerals affecting the streams. Data are being collected by the U.S. Geological Survey (USGS) to determine the magnitude and sources of dissolved minerals during rainfall- and snowmelt-runoff periods. This fact sheet presents results of studies done by the USGS in collaboration with the Animas River Stakeholders Group and was prepared in cooperation with the Southwestern Colorado Water Conservation District. The studies were done at selected sites in the Upper Animas River Basin to determine natural and mining-related sources of dissolved minerals and are continuing in the basin with the Animas River Stakeholders Group and as part of the Department of the Interior Abandoned Mine Lands Initiative. The results of these studies will provide useful information for determining water-quality standards in the basin.

Water insecurity in Canadian Indigenous communities: some inconvenient truths.

PubMed

Sarkar, Atanu; Hanrahan, Maura; Hudson, Amy

2015-01-01

Canada has the second highest per capita water consumption in the world. However, little is known about complex socio-economic and cultural dynamics of water insecurities in Indigenous communities and the multiple health consequences. Most studies have concentrated on a simplified interpretation of accessibility, availability and quality issues, including some common water-borne infections as the only health outcomes. Thus, several government initiatives on potable water supply, particularly for remotely located communities, have failed to sustain and promote a healthy lifestyle. The objective was to explore the water insecurity, coping strategies and associated health risks in a small and isolated sub-Arctic Indigenous (Inuit) community in Canada. The study was based on a community-based survey (2013) in one of the most remote Inuit communities of Labrador. In-depth, open-ended key informant (KI) interviews (community leader (1), woman (1), nurse (1), teacher (1), and elder (1)) and focus group discussions (FGDs) were conducted with community leaders (5), community members (25), women (5), and high school students (8). Convenience sampling was followed in selection of the subjects for FGDs and approached some KIs. All the water sources (five in April and seven in October) were visited and tested for their physical, chemical and microbiological parameters. The FGDs and KI interviews were audio recorded and transcribed. In the analysis, the data (qualitative and quantitative) were broadly categorized into (a) water sources, access and quality, (b) coping, (c) health risks and (d) challenges to run a public water system. The community did not have any piped water supply. Their regular sources of water consisted of several unmonitored local streams, brooks, and ponds. The public water system was not affordable to the majority of community members who solely depended on government aid. Animal fecal contamination (in natural sources such as streams, brooks, and ponds) and the presence of disinfection by-products (in the public water system) were the major quality issues. Gastro-intestinal infections were the most common disease in the community. Per capita water consumption was less than one-third of the Canadian national average (274 L/day/person), severely compromising personal hygiene and water intake. High-sugar-content beverages were the most common alternative to lack of accessible and affordable potable water, particularly for children. Mental stress due to water insecurity and chronic back and shoulder injuries due to carrying heavy water buckets every day were the commonly encountered adverse health outcomes. Water insecurity has put the community at risk of multiple serious adverse health outcomes. The scenario is not unique in Canada. There are many remote Indigenous communities facing similar kinds of water insecurity.

Contamination of groundwater by the fumigants ethylene dibromide (EDB) and dibromochloropropane (DBCP) near McBee, South Carolina

USGS Publications Warehouse

Landmeyer, James E.; Campbell, Bruce G.

2010-01-01

McBee is a small town of about 700 people located in Chesterfield County, South Carolina, in the Sandhills region of the upper Coastal Plain. The halogenated organic compounds ethylene dibromide (EDB) and dibromochloropropane (DBCP) have been detected in several public and domestic supply and irrigation wells since 2002 at concentrations above their U.S. Environmental Protection Agency Maximum Contaminant Limits of 0.05 and 0.2 microgram per liter (µg/L), respectively. The source(s) and release histories of EDB and DBCP to local groundwater are unknown, but believed to be related to their historical use between the 1940s and their ban in the late 1970s as fumigants to control nematode damage in peach orchards. However, gasoline and jet-fuel supplies also contained EDB and are an alternative source of contamination to groundwater. The detection of EDB and DBCP in water wells has raised health concerns because groundwater is the sole source of water supply in the McBee area. In April 2010, forensic, geochemical-based investigation was initiated by the U.S. Geological Survey in cooperation with the Alligator Rural Water & Sewer Company to provide additional data regarding EDB and DBCP in local groundwater. The investigation includes an assessment of the use, release, and disposal history of EDB and DBCP in the area, the distribution of EDB and DBCP concentrations in the unsaturated zone, and transport and fate in groundwater.

SWMM5 Application Programming Interface and PySWMM: A ...

EPA Pesticide Factsheets

In support of the OpenWaterAnalytics open source initiative, the PySWMM project encompasses the development of a Python interfacing wrapper to SWMM5 with parallel ongoing development of the USEPA Stormwater Management Model (SWMM5) application programming interface (API). ... The purpose of this work is to increase the utility of the SWMM dll by creating a Toolkit API for accessing its functionality. The utility of the Toolkit is further enhanced with a wrapper to allow access from the Python scripting language. This work is being prosecuted as part of an Open Source development strategy and is being performed by volunteer software developers.

Contribution of Doñana Wetlands to Carbon Sequestration

PubMed Central

Morris, Edward P.; Flecha, Susana; Figuerola, Jordi; Costas, Eduardo; Navarro, Gabriel; Ruiz, Javier; Rodriguez, Pablo; Huertas, Emma

2013-01-01

Inland and transitional aquatic systems play an important role in global carbon (C) cycling. Yet, the C dynamics of wetlands and floodplains are poorly defined and field data is scarce. Air-water fluxes in the wetlands of Doñana Natural Area (SW Spain) were examined by measuring alkalinity, pH and other physiochemical parameters in a range of water bodies during 2010–2011. Areal fluxes were calculated and, using remote sensing, an estimate of the contribution of aquatic habitats to gaseous transport was derived. Semi-permanent ponds adjacent to the large Guadalquivir estuary acted as mild sinks, whilst temporal wetlands were strong sources of (−0.8 and 36.3 ). Fluxes in semi-permanent streams and ponds changed seasonally; acting as sources in spring-winter and mild sinks in autumn (16.7 and −1.2 ). Overall, Doñana's water bodies were a net annual source of (5.2 ). Up–scaling clarified the overwhelming contribution of seasonal flooding and allochthonous organic matter inputs in determining regional air-water gaseous transport (13.1 ). Nevertheless, this estimate is about 6 times < local marsh net primary production, suggesting the system acts as an annual net sink. Initial indications suggest longer hydroperiods may favour autochthonous C capture by phytoplankton. Direct anthropogenic impacts have reduced the hydroperiod in Doñana and this maybe exacerbated by climate change (less rainfall and more evaporation), suggesting potential for the modification of C sequestration. PMID:23977044

Determination of source process and the tsunami simulation of the 2013 Santa Cruz earthquake

NASA Astrophysics Data System (ADS)

Park, S. C.; Lee, J. W.; Park, E.; Kim, S.

2014-12-01

In order to understand the characteristics of large tsunamigenic earthquakes, we analyzed the earthquake source process of the 2013 Santa Cruz earthquake and simulated the following tsunami. We first estimated the fault length of about 200 km using 3-day aftershock distribution and the source duration of about 110 seconds using the duration of high-frequency energy radiation (Hara, 2007). Moment magnitude was estimated to be 8.0 using the formula of Hara (2007). From the results of 200 km of fault length and 110 seconds of source duration, we used the initial value of rupture velocity as 1.8 km/s for teleseismic waveform inversions. Teleseismic body wave inversion was carried out using the inversion package by Kikuchi and Kanamori (1991). Teleseismic P waveform data from 14 stations were used and band-pass filter of 0.005 ~ 1 Hz was applied. Our best-fit solution indicated that the earthquake occurred on the northwesterly striking (strike = 305) and shallowly dipping (dip = 13) fault plane. Focal depth was determined to be 23 km indicating shallow event. Moment magnitude of 7.8 was obtained showing somewhat smaller than the result obtained above and that of previous study (Lay et al., 2013). Large slip area was seen around the hypocenter. Using the slip distribution obtained by teleseismic waveform inversion, we calculated the surface deformations using formulas of Okada (1985) assuming as the initial change of sea water by tsunami. Then tsunami simulation was carred out using Conell Multi-grid Coupled Tsunami Model (COMCOT) code and 1 min-grid topographic data for water depth from the General Bathymetric Chart of the Ocenas (GEBCO). According to the tsunami simulation, most of tsunami waves propagated to the directions of southwest and northeast which are perpendicular to the fault strike. DART buoy data were used to verify our simulation. In the presentation, we will discuss more details on the results of source process and tsunami simulation and compare them with the previous study.

How should we build a generic open-source water management simulator?

NASA Astrophysics Data System (ADS)

Khadem, M.; Meier, P.; Rheinheimer, D. E.; Padula, S.; Matrosov, E.; Selby, P. D.; Knox, S.; Harou, J. J.

2014-12-01

Increasing water needs for agriculture, industry and cities mean effective and flexible water resource system management tools will remain in high demand. Currently many regions or countries use simulators that have been adapted over time to their unique system properties and water management rules and realities. Most regions operate with a preferred short-list of water management and planning decision support systems. Is there scope for a simulator, shared within the water management community, that could be adapted to different contexts, integrate community contributions, and connect to generic data and model management software? What role could open-source play in such a project? How could a genericuser-interface and data/model management software sustainably be attached to this model or suite of models? Finally, how could such a system effectively leverage existing model formulations, modeling technologies and software? These questions are addressed by the initial work presented here. We introduce a generic water resource simulation formulation that enables and integrates both rule-based and optimization driven technologies. We suggest how it could be linked to other sub-models allowing for detailed agent-based simulation of water management behaviours. An early formulation is applied as an example to the Thames water resource system in the UK. The model uses centralised optimisation to calculate allocations but allows for rule-based operations as well in an effort to represent observed behaviours and rules with fidelity. The model is linked through import/export commands to a generic network model platform named Hydra. Benefits and limitations of the approach are discussed and planned work and potential use cases are outlined.

Controls on compound specific 2H/1H of leaf waxes along a North American monsoonal transect

NASA Astrophysics Data System (ADS)

Berke, M. A.; Tipple, B. J.; Hambach, B.; Ehleringer, J. R.

2013-12-01

The use of hydrogen isotope ratios of sedimentary n-alkanes from leaf waxes has become an important method for the reconstruction of paleohydrologic conditions. Ideally, the relationship between lipid 2H/1H values and source water is one-to-one. But the extent to which the 2H/1H values are altered between initial source water and lipid 2H/1H values varies by plant type and environment. Additionally, these variables may be confounded by use of varied source waters by plants in the same ecosystem. Here, we use a transect study across the arid southwestern landscape of the United States, which is heavily influenced by the North American Monsoon, to study the variability in 2H/1H values of leaf waxes in co-occurring plants from Tucson, Arizona to Salt Lake City, Utah. Perennials, including rabbit brush (Chrysothamnus nauseosus), sagebrush (Artemisia tridentata), and gambel oak (Quercus gambelii) and an annual plant, sunflower (Helianthus annuus), were chosen for their wide geographic distribution along the entire transect. Our results indicate that n-alkane distribution for each plant was similar and generally showed no relationship to environmental variables (elevation, mean annual precipitation, latitude, and temperature). However, we find evidence of n-alkane 2H/1H value relating to transect latitude, a relationship that is weaker for all samples combined than the strong individual correlation for each plant species. Further, these 2H/1H values suggest that not all plants in the monsoon region utilize monsoon-delivered precipitation. These results imply an adaptation to discontinuous spatial coverage and amount of monsoonal precipitation and suggest care must be taken when assuming consistent source water for different plants, particularly in regions with highly seasonal precipitation delivery.

Growth dynamics of Salmonella enterica strains on alfalfa sprouts and in waste seed irrigation water.

PubMed

Howard, Michael B; Hutcheson, Steven W

2003-01-01

Alfalfa sprouts and other seed sprouts have been implicated in numerous outbreaks of salmonellosis. The source of these epidemics appears to have been low-level contamination of seeds by Salmonella bacteria that developed into clinically significant populations during the seed germination process. To test the possibility that Salmonella enterica strains carry host range determinants that allow them to grow on alfalfa, strains isolated from alfalfa or other sources were surveyed for their ability to grow on germinating alfalfa seeds. An S. enterica serovar Cubana strain originally isolated from contaminated alfalfa sprouts multiplied most rapidly during the initial 24 h of the seed germination process. Germinating alfalfa seeds supported the multiplication of S. enterica cells prior to the emergence of the root radicle at 72 h. Thereafter, much lower rates of multiplication were apparent. The ability of S. enterica to grow on germinating alfalfa seeds was independent of the serovar, isolation source, or virulence of the strain. Isolates obtained from alfalfa attained population levels similar to those observed for strains isolated from contaminated meat products or stools. Each of the strains could be detected in the waste irrigation water, with populations being strongly correlated with those detected on the germinating alfalfa seeds. The S. enterica strains were capable of utilizing the waste irrigation water as a sole carbon and nitrogen source. S. enterica strains thus appear to grow saprophytically on soluble organics released from seeds during early phases of germination. The ability to detect S. enterica in the waste irrigation water early in the germination process indicates that this method may be used as a simple way to monitor the contamination of sprouts during commercial operations.

The OPEnSampler: A Low-Cost, Low-Weight, Customizable and Modular Open Source 24-Unit Automatic Water Sampler

NASA Astrophysics Data System (ADS)

Nelke, M.; Selker, J. S.; Udell, C.

2017-12-01

Reliable automatic water samplers allow repetitive sampling of various water sources over long periods of time without requiring a researcher on site, reducing human error as well as the monetary and time costs of traveling to the field, particularly when the scale of the sample period is hours or days. The high fixed cost of buying a commercial sampler with little customizability can be a barrier to research requiring repetitive samples, such as the analysis of septic water pre- and post-treatment. DIY automatic samplers proposed in the past sacrifice maximum volume, customizability, or scope of applications, among other features, in exchange for a lower net cost. The purpose of this project was to develop a low-cost, highly customizable, robust water sampler that is capable of sampling many sources of water for various analytes. A lightweight aluminum-extrusion frame was designed and assembled, chosen for its mounting system, strength, and low cost. Water is drawn from two peristaltic pumps through silicone tubing and directed into 24 foil-lined 250mL bags using solenoid valves. A programmable Arduino Uno microcontroller connected to a circuit board communicates with a battery operated real-time clock, initiating sampling stages. Period and volume settings are programmable in-field by the user via serial commands. The OPEnSampler is an open design, allowing the user to decide what components to use and the modular theme of the frame allows fast mounting of new manufactured or 3D printed components. The 24-bag system weighs less than 10kg and the material cost is under $450. Up to 6L of sample water can be drawn at a rate of 100mL/minute in either direction. Faster flowrates are achieved by using more powerful peristaltic pumps. Future design changes could allow a greater maximum volume by filling the unused space with more containers and adding GSM communications to send real time status information.

Predicting Anthropogenic Noise Contributions to US Waters.

PubMed

Gedamke, Jason; Ferguson, Megan; Harrison, Jolie; Hatch, Leila; Henderson, Laurel; Porter, Michael B; Southall, Brandon L; Van Parijs, Sofie

2016-01-01

To increase understanding of the potential effects of chronic underwater noise in US waters, the National Oceanic and Atmospheric Administration (NOAA) organized two working groups in 2011, collectively called "CetSound," to develop tools to map the density and distribution of cetaceans (CetMap) and predict the contribution of human activities to underwater noise (SoundMap). The SoundMap effort utilized data on density, distribution, acoustic signatures of dominant noise sources, and environmental descriptors to map estimated temporal, spatial, and spectral contributions to background noise. These predicted soundscapes are an initial step toward assessing chronic anthropogenic noise impacts on the ocean's varied acoustic habitats and the animals utilizing them.

Field Operations For The "Intelligent River" Observation System: A Basin-wide Water Quality Observation System In The Savannah River Basin And Platform Supporting Related Diverse Initiatives.

NASA Astrophysics Data System (ADS)

Sutton, A.; Koons, M.; O'Brien-Gayes, P.; Moorer, R.; Hallstrom, J.; Post, C.; Gayes, P. T.

2017-12-01

The Intelligent River (IR) initiative is an NSF sponsored study developing new data management technology for a range of basin-scale applications. The technology developed by Florida Atlantic and Clemson University established a network of real-time reporting water quality sondes; from the mountains to the estuary of the Savannah River basin. Coastal Carolina University led the field operations campaign. Ancillary studies, student projects and initiatives benefitted from the associated instrumentation, infrastructure and operational support of the IR program. This provided a vehicle for students to participate in fieldwork across the watershed and pursue individual interests. Student projects included: 1) a Multibeam sonar survey investigating channel morphology in the area of an IR sensor station and 2) field tests of developing techniques for acquiring and assimilating flood velocity data into model systems associated with a separate NSF Rapid award. The multibeam survey within the lower Savannah basin exhibited a range of complexity in bathymetry, bedforms and bottom habitat in the vicinity of one of the water quality stations. The complex morphology and bottom habitat reflect complex flow patterns, localized areas of depositional and erosive tendencies providing a valuable context for considering point-source water quality time series. Micro- Lagrangian drifters developed by ISENSE at Florida Atlantic University, a sled mounted ADCP, and particle tracking from imagery collected by a photogrammetric drone were tested and used to develop methodology for establishing velocity, direction and discharge levels to validate, initialize and assimilate data into advance models systems during future flood events. The prospect of expanding wide scale observing systems can serve as a platform to integrate small and large-scale cooperative studies across disciplines as well as basic and applied research interests. Such initiatives provide opportunities for embedded education and experience for students that add to the understanding of broad integrated complex systems.

Biological, Physical and Chemical Data From Gulf of Mexico Gravity and Box Core MRD05-04

USGS Publications Warehouse

Osterman, Lisa E.; Campbell, Pamela L.; Swarzenski, Peter W.; Ricardo, John P.

2010-01-01

This paper presents the benthic foraminiferal census data, magnetic susceptibility measurements, vanadium and organic geochemistry (carbon isotope, sterols, and total organic carbon) data from the MRD05-04 gravity and box cores. The MRD05-04 cores were obtained from the Louisiana continental shelf in an on-going initiative to examine the geographic and temporal extent of hypoxia, low-oxygen bottom-water content, and geochemical transport. The development of low-oxygen bottom water conditions in coastal waters is dependent upon a new source of bio-available nutrients introduced into a well-stratified water column. A number of studies have concluded that the development of the current seasonal hypoxia (dissolved oxygen < 2 mg L-1) in subsurface waters of the northern Gulf of Mexico is related to increased transport of nutrients (primarily nitrogen, but possibly also phosphorous) by the Mississippi River. However, the development of earlier episodes of seasonal low-oxygen subsurface water on the Louisiana shelf may be related to Mississippi River discharge.

Sedimentological Control on Hydrate Saturation Distribution in Arctic Gas-Hydrate-Bearing Deposits

NASA Astrophysics Data System (ADS)

Behseresht, J.; Peng, Y.; Bryant, S. L.

2010-12-01

Grain size variations along with the relative rates of fluid phases migrating into the zone of hydrate stability, plays an important role in gas-hydrate distribution and its morphologic characteristics. In the Arctic, strata several meters thick containing large saturations of gas hydrate are often separated by layers containing small but nonzero hydrate saturations. Examples are Mt. Elbert, Alaska and Mallik, NW Territories. We argue that this sandwich type hydrate saturation distribution is consistent with having a gas phase saturation within the sediment when the base of gas hydrate stability zone (BGHSZ) was located above the sediment package. The volume change during hydrate formation process derives movement of fluid phases into the GHSZ. We show that this fluid movement -which is mainly governed by characteristic relative permeability curves of the host sediment-, plays a crucial role in the amount of hydrate saturation in the zone of major hydrate saturation. We develop a mechanistic model that enables estimating the final hydrate saturation from an initial gas/water saturation in sediment with known relative permeability curves. The initial gas/water saturation is predicted using variation of capillary entry pressure with depth, which in turn depends on the variation in grain-size distribution. This model provides a mechanistic approach for explaining large hydrate saturations (60%-75%) observed in zones of major hydrate saturation considering the governing characteristic relative permeability curves of the host sediments. We applied the model on data from Mount Elbert well on the Alaskan North Slope. It is shown that, assuming a cocurrent flow of gas and water into the GHSZ, such large hydrate saturations (up to 75%) cannot result from large initial gas saturations (close to 1-Sw,irr) due to limitations on water flux imposed by typical relative permeability curves. They could however result from modest initial gas saturations (ca. 40%) at which we have reasonable phase mobility ratios required for appropriate relative rates of gas and water transporting into GHSZ to form large hydrate saturations. Nevertheless, from the profile of capillary entry pressure vs. depth, we expect large initial gas saturations and thus the final high hydrate saturation suggests another form of water flow: water moves down through accumulated hydrate from the unfrozen water above. For this to happen the water phase must remain connected within the hydrate-bearing sediment. This seems plausible in hydrate bearing sediments because hydrate formation will be stopped before water saturation gets to very low values (lower than Sw,irr) due to salinity build up. The location of small hydrate saturations (10-15%) is consistent with the location of the residual gas phase established during water imbibition into these locations while they serve as a gas source to the layers above.

Identification of groundwater nitrate sources in pre-alpine catchments: a multi-tracer approach

NASA Astrophysics Data System (ADS)

Stoewer, Myriam; Stumpp, Christine

2014-05-01

Porous aquifers in pre-alpine areas are often used as drinking water resources due to their good water quality status and water yield. Maintaining these resources requires knowledge about possible sources of pollutants and a sustainable management practice in groundwater catchment areas. Of particular interest in agricultural areas, like in pre-alpine regions, is limiting nitrate input as main groundwater pollutant. Therefore, the objective of the presented study is i) to identify main nitrate sources in a pre-alpine groundwater catchment with current low nitrate concentration using stable isotopes of nitrate (d18O and d15N) and ii) to investigate seasonal dynamics of nitrogen compounds. The groundwater catchment areas of four porous aquifers are located in Southern Germany. Most of the land use is organic grassland farming as well as forestry and residential area. Thus, potential sources of nitrate mainly are mineral fertilizer, manure/slurry, leaking sewage system and atmospheric deposition of nitrogen compounds. Monthly freshwater samples (precipitation, river water and groundwater) are analysed for stable isotope of water (d2H, d18O), the concentration of major anions and cations, electrical conductivity, water temperature, pH and oxygen. In addition, isotopic analysis of d18O-NO3- and d15N-NO3- for selected samples is carried out using the denitrifier method. In general, all groundwater samples were oxic (10.0±2.6mg/L) and nitrate concentrations were low (0.2 - 14.6mg/L). The observed nitrate isotope values in the observation area compared to values from local precipitation, sewage, manure and mineral fertilizer as well as to data from literature shows that the nitrate in freshwater samples is of microbial origin. Nitrate derived from ammonium in fertilizers and precipitation as well as from soil nitrogen. It is suggested that a major potential threat to the groundwater quality is ammonia and ammonium at a constant level mainly from agriculture activities as well as continuously release of nitrogen stored in agricultural soils due to mineralization processes. In all groundwater and river water samples a seasonal variation of nitrate sources and concentration is absent but nitrate in precipitation shows a clear seasonal variation with peaks in spring and fall according to agricultural activity. This points to dilution effects of high nitrate inputs due to the large groundwater volume and mean residence time and highlights the function of soil as initial sink for nitrogen compounds delivered by fertilizer. Even though nitrate contamination was low in the study area, the results emphasize the importance of reducing additional nitrate sources in pre-alpine oxic aquifers. This will maintain the good water quality status of the aquifers and enable its use for drinking water supply.

Use of isotopic and hydrometric monitoring methods to partition hydrologic contributions to forested wetlands in the Upper Peninsula of Michigan

NASA Astrophysics Data System (ADS)

Van Grinsven, M. J.; Pypker, T. G.; Kolka, R. K.

2012-12-01

As a result of their landscape position and physical soil properties, northern forested wetlands are capable of retaining springtime snowmelt, rain and near surface groundwater inputs into the growing season. Hydrological conditions such as source water chemistry, duration of inundation, and magnitude of water table fluctuations are affected by the relative contribution of snow, rain, and groundwater sources, and in turn these hydrological conditions strongly influence the structure and function of northern forested wetlands. Black ash (Fraxinus nigra) is a facultative wet tree species, and is known to occur in 23 U.S. states and 7 Canadian provinces in northeastern North America. Black ash trees have ecological, economic, and cultural significance, and are currently threatened by the rapid expansion of the exotic emerald ash borer (Burprestidae: Agrilus planipennis). Since its initial detection in 2002 near Detroit, MI, the emerald ash borer has killed millions of ash trees in 15 U.S. states and 2 Canadian provinces. There is very little known about black ash wetland hydrology and ecology, and as a result of the looming infestation, there is a critical need to gain a better understanding of the hydrology in undisturbed ecosystems. The main objective of this study is to partition source water contributions in black ash wetlands in the western Upper Peninsula of Michigan. We hypothesize that snowmelt and near surface groundwater supply the majority of water to these wetlands annually, and summer rain is readily removed from the system through the evapotranspiration pathway. Hydrometric monitoring methods were used in conjunction with isotopic analysis using a linear mixing model to characterize source water contributions in nine black ash wetlands. The results suggest a connection with near surface groundwater during spring and early summer, and a short residence time for rain water following summer storm events. The outcome of this research aims to inform land managers in northeastern North America about the natural hydrologic condition of black ash wetlands, and provide baseline data that underscores potential water and forest resource impacts of current and future emerald ash borer infestations.

The Role of Soil Water and Land Feedbacks in Decadal Drought in Western North America

NASA Astrophysics Data System (ADS)

Langford, S.; Chikamoto, Y.; Noone, D. C.

2013-12-01

Western North America is susceptible to severe impacts of megadroughts, as evidenced by tree-core or lake sediment records. Future predictions suggest that this region will become more arid, with further consequences for water resources. Understanding the mechanisms of drought variability and persistence in western North America is critical for the eventual development of effective forecasting methods. The ocean is expected to be the main source of decadal memory in the system as the atmosphere varies on a much shorter timescale. The ocean's role in driving the low-frequency variability of the system is potentially predictable. However, low-frequency precipitation anomalies in western North America can occur in the absence of ocean feedbacks. Sea surface temperature anomalies in the north Pacific Ocean only account for around 20 per cent of the low-frequency winter precipitation in California in the CMIP5 historical runs. This is not sufficient to use the skill of global coupled models in predicting ocean conditions ahead of time to successfully forecast the possibility of long-term drought in western North America. Megadroughts therefore may be generated by unpredictable atmospheric noise, or persisted by other sources of low-frequency variability such as land processes and feedbacks. Snowpack in western North America is a crucial water resource for the surrounding communities, storing the winter precipitation for use later in the year. Likewise, soil moisture integrates the precipitation signal; the time scale depends on the depth and characteristics of the soil. Water storage and related variables are more predictable on longer timescales than precipitation, as measured by anomaly correlation for hindcasts compared to a 'perfect model' control run with CESM1.0.3. The importance of antecedent land conditions in persisting megadroughts in western North America is explored with ensemble simulations of CESM1.0.3, where the atmosphere is perturbed at the initiation and peak of a megadrought in the control run. Numerical experiments are used to test land-atmosphere feedbacks or memory sources, highlighting the sensitivity of megadrought initiation, persistence and termination to these antecedent conditions. The model results confirm the importance of land processes in projections of future decadal hydroclimate.

"Know Your Well" A Groundwater Quality Project to Inform Students and Well-Owners

NASA Astrophysics Data System (ADS)

Olson, C.; Snow, D.; Samal, A.; Ray, C.; Kreifels, M.

2017-12-01

Over 15 million U.S. households rely on private, household wells for drinking water, and these sources are not protected under the Safe Drinking Water Act. Data on private well water quality is slowly being collected and evaluated from a number of different agencies, sources and projects. A new project is designed both for training high school students and to help assess the quality of water from rural domestic wells in Nebraska. This "crowd sourced" program engaging high school agricultural education programs, FFA chapters, and science classes with students sampling and testing water sampling from rural domestic wells from 12 districts across the state. Students and teachers from selected school were trained through multiple school visits, both in the classroom and in the field. Classroom visits were used to introduce topics such as water quality and groundwater, and testing methods for specific analytes. During the field visit, students were exposed to field techniques, the importance of accuracy in data collection, and what factors might influence the water in sampled wells. High school students learn to sample and test water independently. Leadership and initiative is developed through the program, and many experience the enlightenment that comes with citizen science. A customized mobile app was developed for ease of data entry and visualization, and data uploaded to a secure website where information was stored and compared to laboratory tests of the same measurements. General water quality parameters, including pH, electrical conductivity, major anions are tested in the field and laboratory, as well as environmental contaminants such as arsenic, uranium, pesticides, bacteria. Test kits provided to each class were used by the students to measure selected parameters, and then duplicate water samples were analyzed at a university laboratory. Five high schools are involved in the project during its first year. Nitrate, bacteria and pesticides represent major concerns for private well owners across the U.S. and preliminary results indicate that nitrate concentrations can range up to 70 mg/L, while detections of bacteria and traces of pesticide residues are consistent with other studies. This project will help both high school students and private well owner become better-informed about water quality in Nebraska.

Research on pathogens at Great Lakes beaches: sampling, influential factors, and potential sources

USGS Publications Warehouse

,

2013-01-01

The overall mission of this work is to provide science-based information and methods that will allow beach managers to more accurately make beach closure and advisory decisions, understand the sources and physical processes affecting beach contaminants, and understand how science-based information can be used to mitigate and restore beaches and protect the public. The U.S. Geological Survey (USGS), in collaboration with many Federal, State, and local agencies and universities, has conducted research on beach health issues in the Great Lakes Region for more than a decade. The work consists of four science elements that align with the USGS Beach Health Initiative Mission: real-time assessments of water quality; coastal processes; pathogens and source tracking; and data analysis, interpretation, and communication. The ongoing or completed research for the pathogens and source tracking topic is described in this fact sheet.

An Examination Of Marine Corps Energy Initiatives And The Supporting Manpower Force Structure

DTIC Science & Technology

2016-03-01

in renewable energy and advancements in bio- fuel technology. The Navy’s energy, environment, and climate change website (2015d) reported that...2016 running off a mix of fossil fuel , biofuel, and nuclear energy. (Photo: MC2 Ryan J. Batchelder/Navy). Source: http://www.navytimes.com/story...Energy and Atmosphere (EA) and Water Efficiency (WE) sections. Offer cost- effective alternative fuel vehicles (AFVs) and coordinate with facility

Integrated Warfighter Biodefense Program (IWBP) - Phase 2

DTIC Science & Technology

2011-03-03

one another or with environments to spread disease such as indirect transmission of cholera via water. In this paper only localized mixing is...from WHO reports and other sources. Cholera , Pneumonia, Malaria, and Hepatitis A were selected as representative diseases as their methods of...A(H1N1) and US NORTHCOM In March 2009, the US identified its first cases of „swine flu‟ in New York. Initial reports of cases in Mexico , where the

The Deterministic Mine Burial Prediction System

DTIC Science & Technology

2009-01-12

or below the water-line, initial linear and angular velocities, and fall angle relative to the mine’s axis of symmetry. Other input data needed...c. Run_DMBP.m: start-up MATLAB script for the program 2. C:\\DMBP\\DMBP_src: This directory contains source code, geotechnical databases, and...approved for public release). b. \\Impact_35: The IMPACT35 model c. \\MakeTPARfiles: scripts for creating wave height and wave period input data from

The Okhotsk Sea Kashevarov Bank Polynya: Its Dependence on Diurnal and Fortnightly Tides and its Initial Formation

NASA Technical Reports Server (NTRS)

Martin, Seelye; Polyakov, Igor; Markus, Thorsten; Drucker, Robert

2003-01-01

Open water areas within the sea ice (polynyas) are sources of intense heat exchange between the ocean and the atmosphere. In this paper, we used microwave and visible/infrared satellite data together with a sea ice model to investigate the polynya opening mechanisms. The satellite data and the model show significant agreement and prove that tides play an active role in the polynya dynamics.

Small-scale, hydrogen-oxidizing-denitrifying bioreactor for treatment of nitrate-contaminated drinking water.

PubMed

Smith, Richard L; Buckwalter, Seanne P; Repert, Deborah A; Miller, Daniel N

2005-05-01

Nitrate removal by hydrogen-coupled denitrification was examined using flow-through, packed-bed bioreactors to develop a small-scale, cost effective system for treating nitrate-contaminated drinking-water supplies. Nitrate removal was accomplished using a Rhodocyclus sp., strain HOD 5, isolated from a sole-source drinking-water aquifer. The autotrophic capacity of the purple non-sulfur photosynthetic bacterium made it particularly adept for this purpose. Initial tests used a commercial bioreactor filled with glass beads and countercurrent, non-sterile flow of an autotrophic, air-saturated, growth medium and hydrogen gas. Complete removal of 2 mM nitrate was achieved for more than 300 days of operation at a 2-h retention time. A low-cost hydrogen generator/bioreactor system was then constructed from readily available materials as a water treatment approach using the Rhodocyclus strain. After initial tests with the growth medium, the constructed system was tested using nitrate-amended drinking water obtained from fractured granite and sandstone aquifers, with moderate and low TDS loads, respectively. Incomplete nitrate removal was evident in both water types, with high-nitrite concentrations in the bioreactor output, due to a pH increase, which inhibited nitrite reduction. This was rectified by including carbon dioxide in the hydrogen stream. Additionally, complete nitrate removal was accomplished with wastewater-impacted surface water, with a concurrent decrease in dissolved organic carbon. The results of this study using three chemically distinct water supplies demonstrate that hydrogen-coupled denitrification can serve as the basis for small-scale remediation and that pilot-scale testing might be the next logical step.

Small-scale, hydrogen-oxidizing-denitrifying bioreactor for treatment of nitrate-contaminated drinking water

USGS Publications Warehouse

Smith, R.L.; Buckwalter, S.P.; Repert, D.A.; Miller, D.N.

2005-01-01

Nitrate removal by hydrogen-coupled denitrification was examined using flow-through, packed-bed bioreactors to develop a small-scale, cost effective system for treating nitrate-contaminated drinking-water supplies. Nitrate removal was accomplished using a Rhodocyclus sp., strain HOD 5, isolated from a sole-source drinking-water aquifer. The autotrophic capacity of the purple non-sulfur photosynthetic bacterium made it particularly adept for this purpose. Initial tests used a commercial bioreactor filled with glass beads and countercurrent, non-sterile flow of an autotrophic, air-saturated, growth medium and hydrogen gas. Complete removal of 2 mM nitrate was achieved for more than 300 days of operation at a 2-h retention time. A low-cost hydrogen generator/bioreactor system was then constructed from readily available materials as a water treatment approach using the Rhodocyclus strain. After initial tests with the growth medium, the constructed system was tested using nitrate-amended drinking water obtained from fractured granite and sandstone aquifers, with moderate and low TDS loads, respectively. Incomplete nitrate removal was evident in both water types, with high-nitrite concentrations in the bioreactor output, due to a pH increase, which inhibited nitrite reduction. This was rectified by including carbon dioxide in the hydrogen stream. Additionally, complete nitrate removal was accomplished with wastewater-impacted surface water, with a concurrent decrease in dissolved organic carbon. The results of this study using three chemically distinct water supplies demonstrate that hydrogen-coupled denitrification can serve as the basis for small-scale remediation and that pilot-scale testing might be the next logical step.

Toward Improving Predictability of Extreme Hydrometeorological Events: the Use of Multi-scale Climate Modeling in the Northern High Plains

NASA Astrophysics Data System (ADS)

Munoz-Arriola, F.; Torres-Alavez, J.; Mohamad Abadi, A.; Walko, R. L.

2014-12-01

Our goal is to investigate possible sources of predictability of hydrometeorological extreme events in the Northern High Plains. Hydrometeorological extreme events are considered the most costly natural phenomena. Water deficits and surpluses highlight how the water-climate interdependence becomes crucial in areas where single activities drive economies such as Agriculture in the NHP. Nonetheless we recognize the Water-Climate interdependence and the regulatory role that human activities play, we still grapple to identify what sources of predictability could be added to flood and drought forecasts. To identify the benefit of multi-scale climate modeling and the role of initial conditions on flood and drought predictability on the NHP, we use the Ocean Land Atmospheric Model (OLAM). OLAM is characterized by a dynamic core with a global geodesic grid with hexagonal (and variably refined) mesh cells and a finite volume discretization of the full compressible Navier Stokes equations, a cut-grid cell method for topography (that reduces error in computational gradient computation and anomalous vertical dispersion). Our hypothesis is that wet conditions will drive OLAM's simulations of precipitation to wetter conditions affecting both flood forecast and drought forecast. To test this hypothesis we simulate precipitation during identified historical flood events followed by drought events in the NHP (i.e. 2011-2012 years). We initialized OLAM with CFS-data 1-10 days previous to a flooding event (as initial conditions) to explore (1) short-term and high-resolution and (2) long-term and coarse-resolution simulations of flood and drought events, respectively. While floods are assessed during a maximum of 15-days refined-mesh simulations, drought is evaluated during the following 15 months. Simulated precipitation will be compared with the Sub-continental Observation Dataset, a gridded 1/16th degree resolution data obtained from climatological stations in Canada, US, and Mexico. This in-progress research will ultimately contribute to integrate OLAM and VIC models and improve predictability of extreme hydrometeorological events.

The use and re-use of unsustainable groundwater for irrigation: A global budget

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grogan, Danielle S.; Wisser, Dominik; Prusevich, Alex

Depletion of groundwater aquifers across the globe has become a significant concern, as groundwater is an important and often unsustainable source of irrigation water. Simultaneously, the field of water resource management has seen a lively debate over the concepts and metrics used to assess the downstream re-use of agricultural runoff, with most studies focusing on surface water balances. Here, we bring these two lines of research together, recognizing that depletion of aquifers leads to large amounts of groundwater entering surface water storages and flows by way of agricultural runoff. While it is clear that groundwater users will be impacted bymore » reductions in groundwater availability, there is a major gap in our understanding of potential impacts downstream of groundwater pumping locations. We find that the volume of unsustainable groundwater that is re-used for irrigation following runoff from agricultural systems is nearly as large as the volume initially extracted from reservoirs for irrigation. Basins in which the volume of irrigation water re-used is equal to or greater than the volume of water initially used (which is possible due to multiple re-use of the same water) contain 33 million hectares of irrigated land and are home to 1.3 billion people. Some studies have called for increasing irrigation efficiency as a solution to water shortages. We find that with 100% irrigation efficiency, global demand for unsustainable groundwater is reduced by 52%, but not eliminated. In many basins, increased irrigation efficiency leads to significantly decreased river low flows; increasing irrigation efficiency to 70% globally decreases total surface water supplies by ~600 km 3 yr –1. Lastly, these findings illustrate that estimates of aquifer depletion alone underestimate the importance of unsustainable groundwater to sustaining surface water systems and irrigated agriculture.« less

The use and re-use of unsustainable groundwater for irrigation: A global budget

DOE PAGES

Grogan, Danielle S.; Wisser, Dominik; Prusevich, Alex; ...

2017-03-08

Depletion of groundwater aquifers across the globe has become a significant concern, as groundwater is an important and often unsustainable source of irrigation water. Simultaneously, the field of water resource management has seen a lively debate over the concepts and metrics used to assess the downstream re-use of agricultural runoff, with most studies focusing on surface water balances. Here, we bring these two lines of research together, recognizing that depletion of aquifers leads to large amounts of groundwater entering surface water storages and flows by way of agricultural runoff. While it is clear that groundwater users will be impacted bymore » reductions in groundwater availability, there is a major gap in our understanding of potential impacts downstream of groundwater pumping locations. We find that the volume of unsustainable groundwater that is re-used for irrigation following runoff from agricultural systems is nearly as large as the volume initially extracted from reservoirs for irrigation. Basins in which the volume of irrigation water re-used is equal to or greater than the volume of water initially used (which is possible due to multiple re-use of the same water) contain 33 million hectares of irrigated land and are home to 1.3 billion people. Some studies have called for increasing irrigation efficiency as a solution to water shortages. We find that with 100% irrigation efficiency, global demand for unsustainable groundwater is reduced by 52%, but not eliminated. In many basins, increased irrigation efficiency leads to significantly decreased river low flows; increasing irrigation efficiency to 70% globally decreases total surface water supplies by ~600 km 3 yr –1. Lastly, these findings illustrate that estimates of aquifer depletion alone underestimate the importance of unsustainable groundwater to sustaining surface water systems and irrigated agriculture.« less

The use and re-use of unsustainable groundwater for irrigation: a global budget

NASA Astrophysics Data System (ADS)

Grogan, Danielle S.; Wisser, Dominik; Prusevich, Alex; Lammers, Richard B.; Frolking, Steve

2017-03-01

Depletion of groundwater aquifers across the globe has become a significant concern, as groundwater is an important and often unsustainable source of irrigation water. Simultaneously, the field of water resource management has seen a lively debate over the concepts and metrics used to assess the downstream re-use of agricultural runoff, with most studies focusing on surface water balances. Here, we bring these two lines of research together, recognizing that depletion of aquifers leads to large amounts of groundwater entering surface water storages and flows by way of agricultural runoff. While it is clear that groundwater users will be impacted by reductions in groundwater availability, there is a major gap in our understanding of potential impacts downstream of groundwater pumping locations. We find that the volume of unsustainable groundwater that is re-used for irrigation following runoff from agricultural systems is nearly as large as the volume initially extracted from reservoirs for irrigation. Basins in which the volume of irrigation water re-used is equal to or greater than the volume of water initially used (which is possible due to multiple re-use of the same water) contain 33 million hectares of irrigated land and are home to 1.3 billion people. Some studies have called for increasing irrigation efficiency as a solution to water shortages. We find that with 100% irrigation efficiency, global demand for unsustainable groundwater is reduced by 52%, but not eliminated. In many basins, increased irrigation efficiency leads to significantly decreased river low flows; increasing irrigation efficiency to 70% globally decreases total surface water supplies by ∽600 km3 yr-1. These findings illustrate that estimates of aquifer depletion alone underestimate the importance of unsustainable groundwater to sustaining surface water systems and irrigated agriculture.

Modeling field-scale cosolvent flooding for DNAPL source zone remediation

NASA Astrophysics Data System (ADS)

Liang, Hailian; Falta, Ronald W.

2008-02-01

A three-dimensional, compositional, multiphase flow simulator was used to model a field-scale test of DNAPL removal by cosolvent flooding. The DNAPL at this site was tetrachloroethylene (PCE), and the flooding solution was an ethanol/water mixture, with up to 95% ethanol. The numerical model, UTCHEM accounts for the equilibrium phase behavior and multiphase flow of a ternary ethanol-PCE-water system. Simulations of enhanced cosolvent flooding using a kinetic interphase mass transfer approach show that when a very high concentration of alcohol is injected, the DNAPL/water/alcohol mixture forms a single phase and local mass transfer limitations become irrelevant. The field simulations were carried out in three steps. At the first level, a simple uncalibrated layered model is developed. This model is capable of roughly reproducing the production well concentrations of alcohol, but not of PCE. A more refined (but uncalibrated) permeability model is able to accurately simulate the breakthrough concentrations of injected alcohol from the production wells, but is unable to accurately predict the PCE removal. The final model uses a calibration of the initial PCE distribution to get good matches with the PCE effluent curves from the extraction wells. It is evident that the effectiveness of DNAPL source zone remediation is mainly affected by characteristics of the spatial heterogeneity of porous media and the variable (and unknown) DNAPL distribution. The inherent uncertainty in the DNAPL distribution at real field sites means that some form of calibration of the initial contaminant distribution will almost always be required to match contaminant effluent breakthrough curves.

Modeling field-scale cosolvent flooding for DNAPL source zone remediation.

PubMed

Liang, Hailian; Falta, Ronald W

2008-02-19

A three-dimensional, compositional, multiphase flow simulator was used to model a field-scale test of DNAPL removal by cosolvent flooding. The DNAPL at this site was tetrachloroethylene (PCE), and the flooding solution was an ethanol/water mixture, with up to 95% ethanol. The numerical model, UTCHEM accounts for the equilibrium phase behavior and multiphase flow of a ternary ethanol-PCE-water system. Simulations of enhanced cosolvent flooding using a kinetic interphase mass transfer approach show that when a very high concentration of alcohol is injected, the DNAPL/water/alcohol mixture forms a single phase and local mass transfer limitations become irrelevant. The field simulations were carried out in three steps. At the first level, a simple uncalibrated layered model is developed. This model is capable of roughly reproducing the production well concentrations of alcohol, but not of PCE. A more refined (but uncalibrated) permeability model is able to accurately simulate the breakthrough concentrations of injected alcohol from the production wells, but is unable to accurately predict the PCE removal. The final model uses a calibration of the initial PCE distribution to get good matches with the PCE effluent curves from the extraction wells. It is evident that the effectiveness of DNAPL source zone remediation is mainly affected by characteristics of the spatial heterogeneity of porous media and the variable (and unknown) DNAPL distribution. The inherent uncertainty in the DNAPL distribution at real field sites means that some form of calibration of the initial contaminant distribution will almost always be required to match contaminant effluent breakthrough curves.

Hg isotopes reveal in-stream processing and legacy inputs in East Fork Poplar Creek, Oak Ridge, Tennessee, USA

DOE PAGES

Demers, Jason D.; Blum, Joel D.; Brooks, Scott C.; ...

2018-03-01

In this paper, natural abundance stable Hg isotope measurements were used to place new constraints on sources, transport, and transformations of Hg along the flow path of East Fork Poplar Creek (EFPC), a point-source contaminated headwater stream in Oak Ridge, Tennessee. Particulate-bound Hg in the water column of EFPC within the Y-12 National Security Complex, was isotopically similar to average metallic Hg(0) used in industry, having a mean δ 202Hg value of -0.42 ± 0.09‰ (1SD) and near-zero Δ 199Hg. On average, particulate fraction δ 202Hg values increased downstream by 0.53‰, while Δ 199Hg decreased by -0.10‰, converging with themore » Hg isotopic composition of the fine fraction of streambed sediment along the 26 km flow path. The dissolved fraction behaved differently. Although initial Δ 199Hg values of the dissolved fraction were also near-zero, these values increased transiently along the flow path. Initial δ 202Hg values of the dissolved fraction were more variable than in the particulate fraction, ranging from -0.44 to 0.18‰ among three seasonal sampling campaigns, but converged to an average δ 202Hg value of 0.01 ± 0.10‰ (1SD) downstream. Dissolved Hg in the hyporheic and riparian pore water had higher and lower δ 202Hg values, respectively, compared to dissolved Hg in stream water. Finally, variations in Hg isotopic composition of the dissolved and suspended fractions along the flow path suggest that: (1) physical processes such as dilution and sedimentation do not fully explain decreases in total mercury concentrations along the flow path; (2) in-stream processes include photochemical reduction, but microbial reduction is likely more dominant; and (3) additional sources of dissolved mercury inputs to EFPC at baseflow during this study predominantly arise from the hyporheic zone.« less

Hg isotopes reveal in-stream processing and legacy inputs in East Fork Poplar Creek, Oak Ridge, Tennessee, USA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Demers, Jason D.; Blum, Joel D.; Brooks, Scott C.

In this paper, natural abundance stable Hg isotope measurements were used to place new constraints on sources, transport, and transformations of Hg along the flow path of East Fork Poplar Creek (EFPC), a point-source contaminated headwater stream in Oak Ridge, Tennessee. Particulate-bound Hg in the water column of EFPC within the Y-12 National Security Complex, was isotopically similar to average metallic Hg(0) used in industry, having a mean δ 202Hg value of -0.42 ± 0.09‰ (1SD) and near-zero Δ 199Hg. On average, particulate fraction δ 202Hg values increased downstream by 0.53‰, while Δ 199Hg decreased by -0.10‰, converging with themore » Hg isotopic composition of the fine fraction of streambed sediment along the 26 km flow path. The dissolved fraction behaved differently. Although initial Δ 199Hg values of the dissolved fraction were also near-zero, these values increased transiently along the flow path. Initial δ 202Hg values of the dissolved fraction were more variable than in the particulate fraction, ranging from -0.44 to 0.18‰ among three seasonal sampling campaigns, but converged to an average δ 202Hg value of 0.01 ± 0.10‰ (1SD) downstream. Dissolved Hg in the hyporheic and riparian pore water had higher and lower δ 202Hg values, respectively, compared to dissolved Hg in stream water. Finally, variations in Hg isotopic composition of the dissolved and suspended fractions along the flow path suggest that: (1) physical processes such as dilution and sedimentation do not fully explain decreases in total mercury concentrations along the flow path; (2) in-stream processes include photochemical reduction, but microbial reduction is likely more dominant; and (3) additional sources of dissolved mercury inputs to EFPC at baseflow during this study predominantly arise from the hyporheic zone.« less

Starting Conditions for Hydrothermal Systems Underneath Martian Craters: Hydrocode Modeling

NASA Technical Reports Server (NTRS)

Pierazzo, E.; Artemieva, N. A.; Ivanov, B. A.

2004-01-01

Mars is the most Earth-like of the Solar System s planets, and the first place to look for any sign of present or past extraterrestrial life. Its surface shows many features indicative of the presence of surface and sub-surface water, while impact cratering and volcanism have provided temporary and local surface heat sources throughout Mars geologic history. Impact craters are widely used ubiquitous indicators for the presence of sub-surface water or ice on Mars. In particular, the presence of significant amounts of ground ice or water would cause impact-induced hydrothermal alteration at Martian impact sites. The realization that hydrothermal systems are possible sites for the origin and early evolution of life on Earth has given rise to the hypothesis that hydrothermal systems may have had the same role on Mars. Rough estimates of the heat generated in impact events have been based on scaling relations, or thermal data based on terrestrial impacts on crystalline basements. Preliminary studies also suggest that melt sheets and target uplift are equally important heat sources for the development of a hydrothermal system, while its lifetime depends on the volume and cooling rate of the heat source, as well as the permeability of the host rocks. We present initial results of two-dimensional (2D) and three-dimensional (3D) simulations of impacts on Mars aimed at constraining the initial conditions for modeling the onset and evolution of a hydrothermal system on the red planet. Simulations of the early stages of impact cratering provide an estimate of the amount of shock melting and the pressure-temperature distribution in the target caused by various impacts on the Martian surface. Modeling of the late stage of crater collapse is necessary to characterize the final thermal state of the target, including crater uplift, and distribution of the heated target material (including the melt pool) and hot ejecta around the crater.

Laboratory investigation of drinking water sources of Kangra, Himachal Pradesh.

PubMed

Thakur, S D; Panda, A K

2012-06-01

A total of 70 drinking water sources including piped water supply (n = 36), ground water sources (n = 24, hand pumps and bore wells) and natural water sources (n = 10, springs/step-wells) from various parts of district Kangra, Himachal Pradesh were investigated for their suitability for drinking purpose by presumptive coliform test. Three samples were collected from each source during different parts of the year. Piped water sources (91.7%) were most contaminated followed by natural water sources (90%) and ground water sources (62.5%). 70.5% of the total water samples (n = 210) were positive for coliforms. All the three samples from 8.3% (n = 3), 37.5% (n = 9) and 10% (n = 1) piped water, ground water and natural sources respectively, were negative for coliform organisms. A variety of organisms including Proteus, Klebsiella, Citrobacter, Escherichia coli (E. coli), Pasteurella, Enterobacter and Serratia liquefaciens were isolated from water samples positive for coliforms in presumptive coliform test. Thermo-tolerant coliform organisms; Escherichia coli, Citrobacter, Klebsiella and Enterobacter were 71.2% (n = 52) of the total bacterial isolations. These findings suggest absence of adequate treatment and disinfection of the water sources supplying drinking water in district Kangra.

Habitability constraints on water-rich exoplanets

NASA Astrophysics Data System (ADS)

Noack, Lena; Höning, Dennis; Rivoldini, Attilio; Heistracher, Clemens; Zimov, Nastasia; Journaux, Baptiste; Lammer, Helmut; Van Hoolst, Tim; Hendrik Bredehöft, Jan

2016-04-01

This research addresses the characterization, modelling, thermal evolution and possible habitability of water-rich exoplanets. Water is necessary for the origin and survival of life as we know it. In the search for habitable worlds, water-rich planets therefore seem obvious candidates. The water layer on such planets could be hundreds of kilometers deep. Depending on the temperature profile and the pressure gradient, it is likely that at great depths a significant part of the water layer is solid high pressure ice. Whether the solid ice layer extends to the bottom of the water layer, or if a shallow lower ocean forms above the silicate mantle, depends amongst others on the thermal state of the planet. We therefore model the thermal evolution of water-rich planets with a 1D parameterized model. Depth-dependent profiles for thermodynamic properties as well as pressure and gravity are obtained by solving the Poisson equation for the gravity and the hydrostatic pressure equation for pre-defined mass and composition (in terms of iron, silicates and water) [1]. For density, equations of state are applied. For the simulation of the thermal evolution of water-rich planets, several parameters (as initial temperatures or layer thicknesses) are unknown. We therefore employ a quantitatve study with more than 20'000 simulations, where we investigated which parameters have the largest influence on the appearance of a lower ocean, i.e. the possible melting of high-pressure ice by heat flowing out of the silicate mantle [2]. We find that the surface temperature has the largest influence on the thickness of water layers, for which a lower ocean can still form between the high-pressure ice layer and the silicate mantle. For higher surface temperatures, not only entirely liquid oceans are possible for deeper water shells, also a liquid ocean can form under high-pressure ice layers of hundreds of kilometer thickness (for a 1 Earth-mass planet). Deeper down, the lower ocean can still appear episodically at the water-mantle boundary (WMB). We also investigated the main paramters influencing the existence of volcanic activity and silicate crust formation. Under deep water layers, the high pressure from the overlying water layer can inhibit melting in the mantle. The main parameters influencing the maximal water layer depth, for which melting is still possible, are indeed the parameters influencing the mantle energy budget, which are the amount of radioactive heat sources and the initial upper mantle temperature. Plate tectonics also has a strong influence on the existence of volcanism. Crustal parameters (initial thickness or heat sources enrichment factor) as well as the ice rheology (i.e. the isolating effect of the ice shell on the mantle) have only a small influence on melting processes in the interior and the formation of crust. [1] L. Noack, A. Rivoldini and T. Van Hoolst 2015: CHIC - Coupling Habitability, Interior and Crust: A new Code for Modeling the Thermal Evolution of Planets and Moons. INFOCOMP 2015, ISSN 2308-3484, ISBN 978-1-61208-416-9, pp. 84-90, IARIA, 2015. [2] L. Noack, D. Höning, A. Rivoldini, C. Heistracher, N. Zimov, B. Journaux, H. Lammer, T. Van Hoolst and J.H. Bredehöft: Water-rich planets: how habitable is a water layer deeper than on Earth? Submitted to Icarus.

A scientifically based nationwide assessment of groundwater quality in the United States

USGS Publications Warehouse

Alley, W.M.; Cohen, P.

1991-01-01

Beginning in 1986, the U.S. Geological Survey began an effort to develop a National Water-Quality Assessment Program. The basic premise underlying this initiative is that a better understanding of the quality of water resources across the country, both surface- and groundwater, is needed to develop effective programs and policies to meet the nation's water-quality concerns. The program will focus on water-quality conditions that are prevalent or large in scale, such as occur from nonpoint sources of pollution or from a high density of point sources. The design of the program is substantially different from the traditional approach of a diffuse national monitoring network. The major activities of the assessment program will be clustered within a set of hydrologic systems (river basins and aquifer systems), referred to as study units. In aggregate, the study units will account for a large part of the nation's water use and represent a wide range of settings across the country. Unique attributes of the program include: (1) the use of consistent study approaches, field and laboratory methods, water-quality measurements, and ancillary data measurements for all study units; (2) the development of a progressive understanding of water-quality conditions and trends in each study unit through long-term studies that rotate periods of intensive data collection and analysis with periods during which the assessment activities are less intensive; and (3) the focus of considerable effort on synthesizing results from among the study units to provide information on regional and national water-quality issues. ?? 1991 Springer-Verlag New York Inc.

SOURCE WATER ASSESSMENT USING GEOGRAPHIC INFORMATION SYSTEMS

EPA Science Inventory

The 1996 amendments to Section 1453 of the Safe Drinking Water Act require the states to establish and implement a Source Water Assessment Program (SWAP). Source water is the water taken from rivers, reservoirs, or wells for use as public drinking water. Source water assessment i...

Adapting water treatment design and operations to the impacts of global climate change

NASA Astrophysics Data System (ADS)

Clark, Robert M.; Li, Zhiwei; Buchberger, Steven G.

2011-12-01

It is anticipated that global climate change will adversely impact source water quality in many areas of the United States and will therefore, potentially, impact the design and operation of current and future water treatment systems. The USEPA has initiated an effort called the Water Resources Adaptation Program (WRAP) which is intended to develop tools and techniques that can assess the impact of global climate change on urban drinking water and wastewater infrastructure. A three step approach for assessing climate change impacts on water treatment operation and design is being persude in this effort. The first step is the stochastic characterization of source water quality, the second step is the application of the USEPA Water Treatment Plant model and the third step is the application of cost algorithms to provide a metric that can be used to assess the coat impact of climate change. A model has been validated using data collected from Cincinnati's Richard Miller Water Treatment Plant for the USEPA Information Collection Rule (ICR) database. An analysis of the water treatment processes in response to assumed perturbations in raw water quality identified TOC, pH, and bromide as the three most important parameters affecting performance of the Miller WTP. The Miller Plant was simulated using the EPA WTP model to examine the impact of these parameters on selected regulated water quality parameters. Uncertainty in influent water quality was analyzed to estimate the risk of violating drinking water maximum contaminant levels (MCLs).Water quality changes in the Ohio River were projected for 2050 using Monte Carlo simulation and the WTP model was used to evaluate the effects of water quality changes on design and operation. Results indicate that the existing Miller WTP might not meet Safe Drinking Water Act MCL requirements for certain extreme future conditions. However, it was found that the risk of MCL violations under future conditions could be controlled by enhancing existing WTP design and operation or by process retrofitting and modification.

Modification of deep waters in Marguerite Bay, western Antarctic Peninsula, caused by topographic overflows

NASA Astrophysics Data System (ADS)

Venables, Hugh J.; Meredith, Michael P.; Brearley, J. Alexander

2017-05-01

Circumpolar Deep Water (CDW) intrudes from the mid-layers of the Antarctic Circumpolar Current onto the shelf of the western Antarctic Peninsula, providing a source of heat and nutrients to the regional ocean. It is well known that CDW is modified as it flows across the shelf, but the mechanisms responsible for this are not fully known. Here, data from underwater gliders with high spatial resolution are used to demonstrate the importance of detailed bathymetry in inducing multiple local mixing events. Clear evidence for overflows is observed in the glider data as water flows along a deep channel with multiple transverse ridges. The ridges block the densest waters, with overflowing water descending several hundred metres to fill subsequent basins. This vertical flow leads to entrainment of overlying colder and fresher water in localised mixing events. Initially this process leads to an increase in bottom temperatures due to the temperature maximum waters descending to greater depths. After several ridges, however, the mixing is sufficient to remove the temperature maximum completely and the entrainment of colder thermocline waters to depth reduces the bottom temperature, to approximately the same as in the source region of Marguerite Trough. Similarly, it is shown that deep waters of Palmer Deep are warmer than at the same depth at the shelf break. The exact details of the transformations observed are heavily dependent on the local bathymetry and water column structure, but glacially-carved troughs and shallow sills are a common feature of the bathymetry of polar shelves, and these types of processes may be a factor in determining the hydrographic conditions close to the coast across a wider area.

Coping with hygiene in South Africa, a water scarce country.

PubMed

Duse, A G; da Silva, M P; Zietsman, I

2003-06-01

The burden of infectious diseases may be reduced by adopting effective infection control measures. Some of these are dependent on the provision of adequate and safe water supplies for maintenance of basic standards of personal, domestic and healthcare hygiene. Consequences of scarce, and sometimes unsafe, waters supplies in South Africa are highlighted with reference to healthcare-associated infections, community acquired infectious intestinal diseases and domestic practices as infection sources. Availability of water in more than 67% of South African municipal hospitals and primary health care facilities (delivered by water tanker in 12.5% of satellite clinics, 5% from river or dam sources, 12.4% relying on rainwater) does not necessarily guarantee that it's quality is safe for utilisation. In the Northern Province and Mpumalanga, water needs to be purified prior to usage in 14.4 and 33% of satellite clinics respectively. Simple, low maintenance and low-cost interventions to maximise use and safety of limited water resources may be implemented: micro-organism (S. dysenteriae) inactivation by direct UV-exposure in sunlight abundant environments, water purification by filtration mechanisms and making use of iron pots in the community for pasteurisation, decontamination and boiling procedures. Education is paramount in promoting healthy domestic food handling practices, changing cultural perceptions of hygiene, hand-washing technique and mechanisms of domestic environmental decontamination. Water provision cannot be separated from other inter-related factors such as sanitation. Although the present government has taken initiatives to reduce the number of people not having access to water by 50% in 2002, provision of sanitation has been slower (>38% inadequate sanitation in 2002). Adoption of integrated environmental management approaches in conjunction with community participation (WASH Campaign--2002), by the government, aims to address the sanitation problems.

Assimilation of Remotely Sensed Evaporative Fraction for Improved Agricultural Irrigation Water Management

NASA Astrophysics Data System (ADS)

Lei, F.; Crow, W. T.; Kustas, W. P.; Yang, Y.; Anderson, M. C.

2017-12-01

Improving the water usage efficiency and maintaining water use sustainability is challenging under rapidly changed natural environments. For decades, extensive field investigations and conceptual/physical numerical modeling have been developed to quantify and track surface water and energy fluxes at different spatial and temporal scales. Meanwhile, with the development of satellite-based sensors, land surface eco-hydrological parameters can be retrieved remotely to supplement ground-based observations. However, both models and remote sensing retrievals contain various sources of errors and an accurate and spatio-temporally continuous simulation and forecasting system at the field-scale is crucial for the efficient water management in agriculture. Specifically, data assimilation technique can optimally integrate measurements acquired from various sources (including in-situ and remotely-sensed data) with numerical models through consideration of different types of uncertainties. In this presentation, we will focus on improving the estimation of water and energy fluxes over a vineyard in California, U.S. A high-resolution remotely-sensed Evaporative Fraction (EF) product from the Atmosphere-Land Exchange Inverse (ALEXI) model will be incorporated into a Soil Vegetation Atmosphere Transfer (SVAT) model via a 2-D data assimilation method. The results will show that both the accuracy and spatial variability of soil water content and evapotranspiration in SVAT model can be enhanced through the assimilation of EF data. Furthermore, we will demonstrate that by taking the optimized soil water flux as initial condition and combining it with weather forecasts, future field water status can be predicted under different irrigation scenarios. Finally, we will discuss the practical potential of these advances by leveraging our numerical experiment for the design of new irrigation strategies and water management techniques.

The energy-water nexus: Potential groundwater-quality degradation associated with petroleum production from shale and tight reservoirs

NASA Astrophysics Data System (ADS)

Kharaka, Y. K.; Gans, K. D.; Conaway, C. H.; Thordsen, J. J.; Thomas, B.

2013-12-01

Oil and natural gas are the main sources of primary energy in the USA, providing 63% of total energy consumption in 2011. Production of petroleum from shale and very low permeability reservoirs has increased substantially due to recent developments in deep horizontal drilling, downhole telemetry and massive multi-stage hydraulic fracturing using ';slick water'. Production of natural gas from shale has increased rapidly, from 0.4 Tcf in 2000, to 6.8 Tcf in 2011, almost 30% of gas production in USA; it is projected to increase to account for 49% of USA gas in 2035. U.S. crude oil production has also increased from 5.0 Mbpd in 2008 to 5.6 Mbpd in 2011; oil from unconventional sources in 2035 is projected to be 0.7 to 2.8 Mbpd, accounting for 36% of domestic production. Hydraulic fracturing is carried out by injecting large volumes (~10,000-50,000 m3/well) of fresh water with added proppant, and organic and inorganic chemicals at high fluid pressures. Approximately 500-5,000 m3/well of water are also used for drilling the wells. The total water used for shale gas wells is relatively low compared to the consumptive total water usage in wet regions (e.g. 0.06% of water for the Marcellus Shale); but is much higher in arid regions (e.g. 0.8% for the Haynesville Shale) where water used could be a significant constraint for gas development because its use could impact the available water supply. Fluid pressure is lowered following hydraulic fracturing, causing the ';flowback' brine, which is a mixture of fracturing fluid and formation water, to return to the surface through the casing. During the 2-3 weeks of the ';flowback' period for a Marcellus Shale well, 10-50% of the fracturing fluid returns to the surface, initially at high rates (~1,000 m3/day), decreasing finally to ~ 50 m3/day. The salinity of the ';flowback' water is initially moderate (45,000 mg/L TDS), reflecting the composition of the fracturing water, and increasing to ~200,000 mg/L TDS. Production of natural gas and produced water follows at ~2-8 m3/day per well. The produced waters from Marcellus Shale, Haynesville and the Bakken are Na-Ca-Cl brines with extremely high salinities (≥200,000 mg/L TDS), high NORMs (up to 10,000 picocuries/L for total Ra) and Rn activities, and toxic inorganic and organic compounds. Also, companies add a large number of disclosed and undisclosed chemicals, including KCl, acids, bactericides, biocides, and corrosion and scale inhibitors to the fracturing fluids to improve production. Potential contamination of groundwater by the natural and added chemicals and NORMs in flow back and produced waters is the major concern, and some communities are also concerned about the possibility of induced seismicity. These concerns may be warranted as results of groundwater investigations indicated that private water wells in parts of Pennsylvania and New York showed an association between shale gas operations and methane contamination of drinking water. However, results of detailed chemical and isotopic compositions of shallow groundwater indicated no contamination from the Na-Cl type Fayetteville 'flowback'/produced waters with salinities of ~20,000 mg/L TDS. A major research effort is needed to minimize potential environmental impacts, especially groundwater contamination, when producing these important new sources of energy.

Ammonia pollution characteristics of centralized drinking water sources in China.

PubMed

Fu, Qing; Zheng, Binghui; Zhao, Xingru; Wang, Lijing; Liu, Changming

2012-01-01

The characteristics of ammonia in drinking water sources in China were evaluated during 2005-2009. The spatial distribution and seasonal changes of ammonia in different types of drinking water sources of 22 provinces, 5 autonomous regions and 4 municipalities were investigated. The levels of ammonia in drinking water sources follow the order of river > lake/reservoir > groundwater. The levels of ammonia concentration in river sources gradually decreased from 2005 to 2008, while no obvious change was observed in the lakes/reservoirs and groundwater drinking water sources. The proportion of the type of drinking water sources is different in different regions. In river drinking water sources, the ammonia level was varied in different regions and changed seasonally. The highest value and wide range of annual ammonia was found in South East region, while the lowest value was found in Southwest region. In lake/reservoir drinking water sources, the ammonia levels were not varied obviously in different regions. In underground drinking water sources, the ammonia levels were varied obviously in different regions due to the geological permeability and the natural features of regions. In the drinking water sources with higher ammonia levels, there are enterprises and wastewater drainages in the protected areas of the drinking water sources.

Impact of Unconventional Energy Development using Hydraulic Fracturing on Louisiana Water Resources Availability.

NASA Astrophysics Data System (ADS)

Unruh, H. G., Sr.; Habib, E. H.; Borrok, D. M.

2017-12-01

Unconventional oil and gas extraction around United States has been deployed significantly in the recent years. The current study focuses on the impact of Hydraulic fracturing (HF) on the sustainability of water resources in Louisiana. This impact is measured by quantifying the stress for current and future scenarios of HF water use in the two-main shale plays in Louisiana, the Haynesville and Tuscaloosa. The assessment is conducted at the HUC-12 fine catchment spatial scale. Initially, sectored stress metrics were calculated for surface and groundwater, respectively, without including HF water use. Demand sectors involved in this first stress estimation are power generation, public supply, industrial, etc. Once both stress metrics were estimated with the reported water sources and uses in Louisiana corresponding to the 2010 year, several scenarios for both sources were evaluated. In the first scenario, a peak year (2011) of HF water use was added as a water demand new category into the stress calculation matrices. The results indicate that a significant variability in the calculated stress metric with and without HF is reflected only for the groundwater sector. On the other hand, surface water sector doesn't seem to be affected for the HF water use. However, this apparent abundant surface water in the catchment, the location of the wells is not always adjacent to the body of water, and then trucking or piping of water may be required. For this reason, availability of groundwater in situ is a relevant factor in terms of production cost. Additional tested scenarios consist of increasing the number of wells in both shale play locations. Existing wells scenario calculates the stress including the water use of the total number of wells that currently exist in both shale plays in a short period (one year). The other additional tested scenario consists of increase of 100% of the required number of wells to extract the expected total shale play capacity. Results of the additional scenarios follow the same pattern as the first scenario. This analysis can be useful for water management authorities to consider recycled flow-back as an alternative resource for HF water use. Additionally, a cost analysis can be developed in a future study analyzing the economic feasibility of treating and reusing the wastewater as a source in the HF process.

Availability of environmental radioactivity to honey bee colonies at Los Alamos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hakonson, T.E.; Bostick, K.V.

Data are presented on the availability of tritium, cesium 137, and plutonium to honey bee colonies foraging in the environment surrounding the Los Alamos Scientific Laboratory. Sources of these radionuclides in the laboratory environs include liquid and atmospheric effluents and buried solid waste. Honey bee colonies were placed in three canyon liquid waste disposal areas and were sampled frequently, along with honey, surface water, and surrounding vegetation, to qualitatively determine the availability of these radionuclides to bees (Apis mellifera) and to identify potential food chain sources of the elements. Tritium concentrations in bee and honey samples from the canyons increasedmore » rapidly from initial values of <1 pCi/ml moisture to as much as 9.2 nCi/ml in 75 days after placement of the hives in the canyons. Seasonal patterns in foraging activities as influenced by weather and food availability were apparent in the data. It appears that several sources of tritium were utilized by the colonies, including surface water in the canyons and vegetation receiving tritium from atmospheric effluents and buried solid waste. Concentrations of cesium 137 and plutonium were generally low or undetectable in bees throughout the study. However, levels of both nuclides increased by factors of 10 to 20 in bees from two of the canyon study areas during a 3-month period in 1973. It was speculated that the liquid effluents in the two canyons were the source of the increased concentrations in bee samples, since this water was the only significant source of /sup 137/Cs in the environs. The existence of at least three radionuclide sources in the Los Alamos Scientific Laboratory (LASL) environs complicates the interpretation of the data. However, it is apparent that honey bees can acquire /sup 3/H, /sup 137/Cs, and Pu from multiple sources in the environs.« less

Lead in school drinking water: Canada can and should address this important ongoing exposure source.

PubMed

Barn, Prabjit; Kosatsky, Tom

2011-01-01

Reducing all preventable lead exposures in children should be a public health priority given that blood lead levels in children that were once considered "safe" have since been associated with important neuro-developmental deficits. Limited Canadian data indicate that school drinking water can be an important component of children's overall exposure to lead. Outside of Ontario, however, Canadian schools are not required to test for lead in water; in most of Canada, school testing is case by case, typically initiated by parental concerns. Provinces and territories are encouraged to follow Ontario's example by instituting a routine school water lead testing program in order to identify facilities where action can result in a decrease in students' exposure to lead. Testing and remediation frameworks developed by the US Environmental Protection Agency, Health Canada, and the province of Ontario provide direction to school boards and local and provincial/territorial health authorities.

Trapping of water vapor from an atmosphere by condensed silicate matter formed by high-temperature pulse vaporization

NASA Technical Reports Server (NTRS)

Gerasimov, M. V.; Dikov, Yu. P.; Yakovlev, O. I.; Wlotzka, F.

1993-01-01

The origin of planetary atmospheres is thought to be the result of bombardment of a growing planet by massive planetesimals. According to some models, the accumulation of released water vapor and/or carbon dioxide can result in the formation of a dense and hot primordial atmosphere. Among source and sink processes of atmospheric water vapor the formation of hydroxides was considered mainly as rehydration of dehydrated minerals (foresterite and enstatite). From our point of view, the formation of hydroxides is not limited to rehydration. Condensation of small silicate particles in a spreading vapor cloud and their interaction with a wet atmosphere can also result in the origin of hydrated phases which have no genetic connections with initial water bearing minerals. We present results of two experiments of a simulated interaction of condensed silicate matter which originated during vaporization of dry clinopyroxene in a wet helium atmosphere.

Microwave (SSM/I) Estimates of the Precipitation Rate to Improve Numerical Atmospheric Model Forecasts

NASA Technical Reports Server (NTRS)

Raymond, William H.; Olson, William S.

1990-01-01

Delay in the spin-up of precipitation early in numerical atmospheric forecasts is a deficiency correctable by diabatic initialization combined with diabatic forcing. For either to be effective requires some knowledge of the magnitude and vertical placement of the latent heating fields. Until recently the best source of cloud and rain water data was the remotely sensed vertical integrated precipitation rate or liquid water content. Vertical placement of the condensation remains unknown. Some information about the vertical distribution of the heating rates and precipitating liquid water and ice can be obtained from retrieval techniques that use a physical model of precipitating clouds to refine and improve the interpretation of the remotely sensed data. A description of this procedure and an examination of its 3-D liquid water products, along with improved modeling methods that enhance or speed-up storm development is discussed.

Nutrients and water masses in the Gulf of Maine - Georges Bank region: Variability and importance to blooms of the toxic dinoflagellate Alexandrium fundyense.

PubMed

Townsend, D W; McGillicuddy, D J; Thomas, M A; Rebuck, N R

2014-05-01

We report here the results of ten oceanographic survey cruises carried out in the Gulf of Maine - Georges Bank region of the Northwest Atlantic during the late spring to summer period in 2007, 2008 and 2010, for which we examine and characterize relationships among dissolved inorganic nutrient fields, water mass dynamics and cell densities of the toxic dinoflagellate Alexandrium fundyense . Nutrients are supplied to continental shelf waters of the Gulf of Maine - Georges Bank region by inflows of deep offshore water masses; once in the Gulf they are transported with the residual circulation and mix with surface waters, both in the Gulf and on the Bank. Those fluxes of offshore water masses and their nutrient loads are the major source of nutrients for phytoplankton production in the region, including annual blooms of A. fundyense in the Gulf and on Georges Bank. This much is already known. We suggest here that the locations and magnitude of A. fundyense blooms are controlled in part by variable nutrient fluxes to the interior Gulf of Maine from offshore, and, those interior Gulf of Maine waters are, in turn, the main nutrient source to Georges Bank, which are brought onto the Bank by tidal pumping on the Northern Flank. We present evidence that nitrate is the initial form of nitrogenous nutrient for A. fundyense blooms, but it is quickly depleted to limiting concentrations of less than 0.5 μM, at which time continued growth and maintenance of the population is likely fueled by recycled ammonium. We also show that phosphate may be the limiting nutrient over much of Georges Bank in summer, allowing recycled ammonium concentrations to increase. Our temperature-salinity analyses reveal spatial and temporal (seasonal and interannual) variability in the relative proportions of two deep source waters that enter the Gulf of Maine at depth through the Northeast Channel: Warm Slope Water (WSW) and Labrador Slope Water (LSW). Those two source waters are known to vary in their nutrient loads, with nitrate concentrations about 50% higher in WSW than LSW, for example, and as such the proportions of these two water masses to one another are important determinants of the overall nutrient loads in the interior Gulf. In addition to these deep slope water fluxes, we show evidence here of episodic fluxes of relatively fresh and low-nutrient shelf waters from the Nova Scotian Shelf, which enter the Gulf in pulses at depths between the surface and approximately 150 m, displacing deep slope waters, and consequently they significantly dilute the Gulf's interior waters, reducing nutrient concentrations and, in turn, affect the magnitude of A. fundyense blooms.

Nutrients and water masses in the Gulf of Maine - Georges Bank region: Variability and importance to blooms of the toxic dinoflagellate Alexandrium fundyense

PubMed Central

Townsend, D.W.; McGillicuddy, D.J.; Thomas, M.A.; Rebuck, N.R.

2015-01-01

We report here the results of ten oceanographic survey cruises carried out in the Gulf of Maine - Georges Bank region of the Northwest Atlantic during the late spring to summer period in 2007, 2008 and 2010, for which we examine and characterize relationships among dissolved inorganic nutrient fields, water mass dynamics and cell densities of the toxic dinoflagellate Alexandrium fundyense. Nutrients are supplied to continental shelf waters of the Gulf of Maine - Georges Bank region by inflows of deep offshore water masses; once in the Gulf they are transported with the residual circulation and mix with surface waters, both in the Gulf and on the Bank. Those fluxes of offshore water masses and their nutrient loads are the major source of nutrients for phytoplankton production in the region, including annual blooms of A. fundyense in the Gulf and on Georges Bank. This much is already known. We suggest here that the locations and magnitude of A. fundyense blooms are controlled in part by variable nutrient fluxes to the interior Gulf of Maine from offshore, and, those interior Gulf of Maine waters are, in turn, the main nutrient source to Georges Bank, which are brought onto the Bank by tidal pumping on the Northern Flank. We present evidence that nitrate is the initial form of nitrogenous nutrient for A. fundyense blooms, but it is quickly depleted to limiting concentrations of less than 0.5 μM, at which time continued growth and maintenance of the population is likely fueled by recycled ammonium. We also show that phosphate may be the limiting nutrient over much of Georges Bank in summer, allowing recycled ammonium concentrations to increase. Our temperature-salinity analyses reveal spatial and temporal (seasonal and interannual) variability in the relative proportions of two deep source waters that enter the Gulf of Maine at depth through the Northeast Channel: Warm Slope Water (WSW) and Labrador Slope Water (LSW). Those two source waters are known to vary in their nutrient loads, with nitrate concentrations about 50% higher in WSW than LSW, for example, and as such the proportions of these two water masses to one another are important determinants of the overall nutrient loads in the interior Gulf. In addition to these deep slope water fluxes, we show evidence here of episodic fluxes of relatively fresh and low-nutrient shelf waters from the Nova Scotian Shelf, which enter the Gulf in pulses at depths between the surface and approximately 150 m, displacing deep slope waters, and consequently they significantly dilute the Gulf's interior waters, reducing nutrient concentrations and, in turn, affect the magnitude of A. fundyense blooms. PMID:26028824

Untrapping Kinetically Trapped Ions: The Role of Water Vapor and Ion-Source Activation Conditions on the Gas-Phase Protomer Ratio of Benzocaine Revealed by Ion-Mobility Mass Spectrometry.

PubMed

Xia, Hanxue; Attygalle, Athula B

2017-12-01

The role of water vapor in transforming the thermodynamically preferred species of protonated benzocaine to the less favored protomer was investigated using helium-plasma ionization (HePI) in conjunction with ion-mobility mass spectrometry (IM-MS). The IM arrival-time distribution (ATD) recorded from a neat benzocaine sample desorbed to the gas phase by a stream of dry nitrogen and ionized by HePI showed essentially one peak for the O-protonated species. However, when water vapor was introduced to the enclosed ion source, within a span of about 150 ms the ATD profile changed completely to one dominated by the N-protonated species. Under spray-based ionization conditions, the nature and composition of the solvents have been postulated to play a decisive role in defining the manifested protomer ratios. In reality, the solvent vapors present in the ion source (particularly the ambient humidity) indirectly dictate the gas-phase ratio of the protomers. Evidently, the gas-phase protomer ratio established at the confinement of the ions is readjusted by the ion-activation that takes place during the transmission of ions to the vacuum. Although it has been repeatedly stated that ions can retain a "memory" of their solution structures because they can be kinetically trapped, and thereby represent their solution-based stabilities, we show that the initial airborne ions can undergo significant transformations in the transit through the intermediate vacuum zones between the ion source and the mass detector. In this context, we demonstrate that the kinetically trapped N-protomer of benzocaine can be untrapped by reducing the humidity of the enclosed ion source. Graphical Abstract ᅟ.

Untrapping Kinetically Trapped Ions: The Role of Water Vapor and Ion-Source Activation Conditions on the Gas-Phase Protomer Ratio of Benzocaine Revealed by Ion-Mobility Mass Spectrometry

NASA Astrophysics Data System (ADS)

Xia, Hanxue; Attygalle, Athula B.

2017-12-01

The role of water vapor in transforming the thermodynamically preferred species of protonated benzocaine to the less favored protomer was investigated using helium-plasma ionization (HePI) in conjunction with ion-mobility mass spectrometry (IM-MS). The IM arrival-time distribution (ATD) recorded from a neat benzocaine sample desorbed to the gas phase by a stream of dry nitrogen and ionized by HePI showed essentially one peak for the O-protonated species. However, when water vapor was introduced to the enclosed ion source, within a span of about 150 ms the ATD profile changed completely to one dominated by the N-protonated species. Under spray-based ionization conditions, the nature and composition of the solvents have been postulated to play a decisive role in defining the manifested protomer ratios. In reality, the solvent vapors present in the ion source (particularly the ambient humidity) indirectly dictate the gas-phase ratio of the protomers. Evidently, the gas-phase protomer ratio established at the confinement of the ions is readjusted by the ion-activation that takes place during the transmission of ions to the vacuum. Although it has been repeatedly stated that ions can retain a "memory" of their solution structures because they can be kinetically trapped, and thereby represent their solution-based stabilities, we show that the initial airborne ions can undergo significant transformations in the transit through the intermediate vacuum zones between the ion source and the mass detector. In this context, we demonstrate that the kinetically trapped N-protomer of benzocaine can be untrapped by reducing the humidity of the enclosed ion source. [Figure not available: see fulltext.

Elevated atmospheric escape of atomic hydrogen from Mars induced by high-altitude water

NASA Astrophysics Data System (ADS)

Chaffin, M. S.; Deighan, J.; Schneider, N. M.; Stewart, A. I. F.

2017-01-01

Atmospheric loss has controlled the history of Martian habitability, removing most of the planet’s initial water through atomic hydrogen and oxygen escape from the upper atmosphere to space. In standard models, H and O escape in a stoichiometric 2:1 ratio because H reaches the upper atmosphere via long-lived molecular hydrogen, whose abundance is regulated by a photochemical feedback sensitive to atmospheric oxygen content. The relatively constant escape rates these models predict are inconsistent with known H escape variations of more than an order of magnitude on seasonal timescales, variation that requires escaping H to have a source other than H2. The best candidate source is high-altitude water, detected by the Mars Express spacecraft in seasonally variable concentrations. Here we use a one-dimensional time-dependent photochemical model to show that the introduction of high-altitude water can produce a large increase in the H escape rate on a timescale of weeks, quantitatively linking these observations. This H escape pathway produces prompt H loss that is not immediately balanced by O escape, influencing the oxidation state of the atmosphere for millions of years. Martian atmospheric water loss may be dominated by escape via this pathway, which may therefore potentially control the planet’s atmospheric chemistry. Our findings highlight the influence that seasonal atmospheric variability can have on planetary evolution.

Poly(n-vinylpyrrolidone) hydrogels: 2.Hydrogel composites as wound dressing for tropical environment

NASA Astrophysics Data System (ADS)

Himly, N.; Darwis, D.; Hardiningsih, L.

1993-10-01

POLY(N-VINYLPYRROLIDONE) HYDROGELS: 2. HYDROGEL COMPOSITES AS WOUND DRESSING FOR TROPICAL ENVIRONMENT. The effects of irradiation on hydration and other properties of poly(vinylpyrrolidone) (PVP) hydrogel composites have been investigated. The aqueous solution of vinylpyrrolidone (VP) 10 wt % was mixed with several additives such as agar and polyethylen glycol (PEG). The solution was then irradiated with gamma rays from Cobalt-60 source at room temperature. Several parameters such as elongation at break (EB), tensile strength (TS), degree of swelling (DS), water vapor transmission rate (WVTR), equilibrium water content (EWC), microbial growth and penetration test, and water activity (Aw) were analysed at room temperature of 29 ±2°C humidity of 80 ± 10%. Results show that elongation at break of hydrogel membranes with initial composition of VP with agar, VP with agar and PEG were 240 % and 250 % kGy, the equilibrium water content of membranes were 96 to 90%, whereas degree of swelling were 55 to 10. The WVTR of hydrogel membranes with initial composition of VP with agar and PEG was 70 g m -2h -1, while the water activity was 0.9. Such hydrogel membranes exhibits the following properties: They are elastic, transparent, flexible, impermeable for bacteria. They absopt a high capacity of water, attached to healthy skin but not to the wound and they are easy to remove. These properties of the hydrogel membranes allow for applying as a wound dressings in tropical environment.

An Open Source Framework for Coupled Hydro-Hydrogeo-Chemical Systems in Catchment Research

NASA Astrophysics Data System (ADS)

Delfs, J.; Sachse, A.; Gayler, S.; Grathwohl, P.; He, W.; Jang, E.; Kalbacher, T.; Klein, C.; Kolditz, O.; Maier, U.; Priesack, E.; Rink, K.; Selle, B.; Shao, H.; Singh, A. K.; Streck, T.; Sun, Y.; Wang, W.; Walther, M.

2013-12-01

This poster presents an open-source framework designed to assist water scientists in the study of catchment hydraulic functions with associated chemical processes, e.g. contaminant degradation, plant nutrient turnover. The model successfully calculates the feedbacks between surface water, subsurface water and air in standard benchmarks. In specific model applications to heterogeneous catchments, subsurface water is driven by density variations and runs through double porous media. Software codes of water science are tightly coupled by iteration, namely the Storm Water Management Model (SWMM) for urban runoff, Expert-N for simulating water fluxes and nutrient turnover in agricultural and forested soils, and OpenGeoSys (OGS) for groundwater. The coupled model calculates flow of hydrostatic shallow water over the land surface with finite volume and difference methods. The flow equations for water in the porous subsurface are discretized in space with finite elements. Chemical components are transferred through 1D, 2D or 3D watershed representations with advection-dispersion solvers or, as an alternative, random walk particle tracking. A transport solver can be in sequence with a chemical solver, e.g. PHREEQ-C, BRNS, additionally. Besides coupled partial differential equations, the concept of hydrological response units is employed in simulations at regional scale with scarce data availability. In this case, a conceptual hydrological model, specifically the Jena Adaptable Modeling System (JAMS), passes groundwater recharge through a software interface into OGS, which solves the partial differential equations of groundwater flow. Most components of the modeling framework are open source and can be modified for individual purposes. Applications range from temperate climate regions in Germany (Ammer catchment and Hessian Ried) to arid regions in the Middle East (Oman and Dead See). Some of the presented examples originate from intensively monitored research sites of the WESS research centre and the monitoring initiative TERENO. Other examples originate from the IWAS project on integrated water resources management. The model applications are primarily concerned with groundwater resources, which are endangered by overexploitation, intrusion of saltwater, and nitrate loads.

Using Naturally Occurring Radionuclides To Determine Drinking Water Age in a Community Water System.

PubMed

Waples, James T; Bordewyk, Jason K; Knesting, Kristina M; Orlandini, Kent A

2015-08-18

Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of (90)Y/(90)Sr and (234)Th/(238)U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (σest: ± 3.8 h, P < 0.0001, r(2) = 0.998, n = 11) and 25 days old (σest: ± 13.3 h, P < 0.0001, r(2) = 0.996, n = 12), respectively. Moreover, (90)Y-derived water ages in a community water system (6.8 × 10(4) m(3) d(-1) capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.

Biodegradation of multiple microcystins and cylindrospermopsin in clarifier sludge and a drinking water source: Effects of particulate attached bacteria and phycocyanin.

PubMed

Maghsoudi, Ehsan; Fortin, Nathalie; Greer, Charles; Duy, Sung Vo; Fayad, Paul; Sauvé, Sébastien; Prévost, Michèle; Dorner, Sarah

2015-10-01

The effects of particulate attached bacteria (PAB) and phycocyanin on the simultaneous biodegradation of a mixture of microcystin-LR, YR, LY, LW, LF and cylindrospermopsin (CYN) was assessed in clarifier sludge of a drinking water treatment plant (DWTP) and in a drinking water source. The biomass from lake water and clarifier sludge was able to degrade all microcystins (MCs) at initial concentrations of 10µgL(-1) with pseudo-first order reaction half-lives ranging from 2.3 to 8.8 days. CYN was degraded only in the sludge with a biodegradation rate of 1.0×10(-1)d(-1) and a half-life of 6.0 days. This is the first study reporting multiple MCs and CYN biodegradation in the coagulation-flocculation sludge of a DWTP. The removal of PAB from the lake water and the sludge prolonged the lag time substantially, such that no biodegradation of MCLY, LW and LF was observed within 24 days. Biodegradation rates were shown to increase in the presence of C-phycocyanin as a supplementary carbon source for indigenous bacteria, a cyanobacterial product that accompanies cyanotoxins during cyanobacteria blooms. MCs in mixtures degraded more slowly (or not at all) than if they were degraded individually, an important outcome as MCs in the environment are often present in mixtures. The results from this study showed that the majority of the bacterial biomass responsible for the biodegradation of cyanotoxins is associated with particles or biological flocs and there is a potential for extreme accumulation of cyanotoxins within the DWTP during a transient bloom. Copyright © 2015 Elsevier Inc. All rights reserved.

Village-Level Identification of Nitrate Sources: Collaboration of Experts and Local Population in Benin, Africa

NASA Astrophysics Data System (ADS)

Crane, P.; Silliman, S. E.; Boukari, M.; Atoro, I.; Azonsi, F.

2005-12-01

Deteriorating groundwater quality, as represented by high nitrates, in the Colline province of Benin, West Africa was identified by the Benin national water agency, Direction Hydraulique. For unknown reasons the Colline province had consistently higher nitrate levels than any other region of the country. In an effort to address this water quality issue, a collaborative team was created that incorporated professionals from the Universite d'Abomey-Calavi (Benin), the University of Notre Dame (USA), Direction l'Hydraulique (a government water agency in Benin), Centre Afrika Obota (an educational NGO in Benin), and the local population of the village of Adourekoman. The goals of the project were to: (i) identify the source of nitrates, (ii) test field techniques for long term, local monitoring, and (iii) identify possible solutions to the high levels of groundwater nitrates. In order to accomplish these goals, the following methods were utilized: regional sampling of groundwater quality, field methods that allowed the local population to regularly monitor village groundwater quality, isotopic analysis, and sociological methods of surveys, focus groups, and observations. It is through the combination of these multi-disciplinary methods that all three goals were successfully addressed leading to preliminary identification of the sources of nitrates in the village of Adourekoman, confirmation of utility of field techniques, and initial assessment of possible solutions to the contamination problem.

Spallation Neutron Source Materials Studies

NASA Astrophysics Data System (ADS)

Sommer, W. F.

1998-04-01

Operation of accelerator facilities such as Los Alamos Neutron Science Center (LANSCE), ISIS at Rutherford Appleton Laboratory, the Swiss Institute Neutron Source (SINQ) at Paul Scherrer Institute, and others has provided valuable information on materials performance in high energy particle beams and high energy neutron environments. The Accelerator Production of Tritium (APT) project is sponsoring an extensive series of tests on the effect of spallation neutron source environments to physical and mechanical properties of candidate materials such as nickel-based alloys, stainless steel alloys, aluminum alloys and solid target materials such as tungsten. Measurements of corrosion rates of these candidate materials during irradiation and while in contact with flowing coolant water are being made. The APT tests use the irradiation facility in the beam stop area of the LANSCE accelerator using 800 MeV protons as well as the neutron flux-spectrum generated as these protons interact with targets. The initial irradiations were completed in summer 1997, exposing materials to a fluence approaching 4-6 x 10^21 protons/cm^2. Sample retrieval is now underway. Mechanical properties measurements are being conducted at several laboratories. Studies on components used in service have also been initiated.

Drought Water Right Curtailment

NASA Astrophysics Data System (ADS)

Walker, W.; Tweet, A.; Magnuson-Skeels, B.; Whittington, C.; Arnold, B.; Lund, J. R.

2016-12-01

California's water rights system allocates water based on priority, where lower priority, "junior" rights are curtailed first in a drought. The Drought Water Rights Allocation Tool (DWRAT) was developed to integrate water right allocation models with legal objectives to suggest water rights curtailments during drought. DWRAT incorporates water right use and priorities with a flow-forecasting model to mathematically represent water law and hydrology and suggest water allocations among water rights holders. DWRAT is compiled within an Excel workbook, with an interface and an open-source solver. By implementing California water rights law as an algorithm, DWRAT provides a precise and transparent framework for the complicated and often controversial technical aspects of curtailing water rights use during drought. DWRAT models have been developed for use in the Eel, Russian, and Sacramento river basins. In this study, an initial DWRAT model has been developed for the San Joaquin watershed, which incorporates all water rights holders in the basin and reference gage flows for major tributaries. The San Joaquin DWRAT can assess water allocation reliability by determining probability of rights holders' curtailment for a range of hydrologic conditions. Forecasted flow values can be input to the model to provide decision makers with the ability to make curtailment and water supply strategy decisions. Environmental flow allocations will be further integrated into the model to protect and improve ecosystem water reliability.

19 CFR 10.532 - Integrated Sourcing Initiative.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 19 Customs Duties 1 2010-04-01 2010-04-01 false Integrated Sourcing Initiative. 10.532 Section 10... Trade Agreement Rules of Origin § 10.532 Integrated Sourcing Initiative. (a) For purposes of General... Sourcing Initiative if: (1) The good, in its condition as imported, is both classified in a tariff...

The microbial quality of drinking water in Manonyane community: Maseru District (Lesotho).

PubMed

Gwimbi, P

2011-09-01

Provision of good quality household drinking water is an important means of improving public health in rural communities especially in Africa; and is the rationale behind protecting drinking water sources and promoting healthy practices at and around such sources. To examine the microbial content of drinking water from different types of drinking water sources in Manonyane community of Lesotho. The community's hygienic practices around the water sources are also assessed to establish their contribution to water quality. Water samples from thirty five water sources comprising 22 springs, 6 open wells, 6 boreholes and 1 open reservoir were assessed. Total coliform and Escherichia coli bacteria were analyzed in water sampled. Results of the tests were compared with the prescribed World Health Organization desirable limits. A household survey and field observations were conducted to assess the hygienic conditions and practices at and around the water sources. Total coliform were detected in 97% and Escherichia coli in 71% of the water samples. The concentration levels of Total coliform and Escherichia coli were above the permissible limits of the World Health Organization drinking water quality guidelines in each case. Protected sources had significantly less number of colony forming units (cfu) per 100 ml of water sample compared to unprotected sources (56% versus 95%, p < 0.05). Similarly in terms of Escherichia coli, protected sources had less counts (7% versus 40%, p < 0.05) compared with those from unprotected sources. Hygiene conditions and practices that seemed to potentially contribute increased total coliform and Escherichia coli counts included non protection of water sources from livestock faeces, laundry practices, and water sources being down slope of pit latrines in some cases. These findings suggest source water protection and good hygiene practices can improve the quality of household drinking water where disinfection is not available. The results also suggest important lines of inquiry and provide support and input for environmental and public health programmes, particularly those related to water and sanitation.

Biosorption of Nickel from Industrial Wastewater using Zygnema sp.

NASA Astrophysics Data System (ADS)

Sivaprakash, Kanchana; Blessi T. L., Adlin; Madhavan, Jeyanthi

2015-12-01

Contamination of water sources with heavy metals is a very important pollution problem in the current scenario. Biosorption is an effective method for the removal of heavy metal ions from wastewaters. In this study, the removal of Nickel(II) ions from electroplating industrial wastewater using biosorbent prepared from fresh water algal biomass Zygnema was investigated under batch mode. The sorption efficiency of nickel on Zygnema sp. was evaluated as a function of time, pH and sorbent dosage. The Nickel(II) uptake was dependent on initial pH with pH 3 being the optimum value. For 100 mg/L initial Nickel(II) concentration, sorption equilibrium was attained at a contact time of 100 min. The sorbent dosage affected the biosorption efficiency and maximum removal of 76.4 % was obtained at a dosage of 7.5 g/L. From the performance studies, algal biosorbent Zygnema is found to be a valuable material for the removal of Nickel from industrial wastewater and a better substitute for the conventional adsorbents.

Removal of methyl orange and methylene blue dyes from aqueous solution using lala clam (Orbicularia orbiculata) shell

NASA Astrophysics Data System (ADS)

Eljiedi, Arwa Alseddig Ahmed; Kamari, Azlan

2017-05-01

Textile effluents are considered as potential sources of water pollution because they contain toxic dyes. In the present study, lala clam shell was used as an alternative low-cost adsorbent for the removal of two harmful dyes, namely methyl orange (MO) and methylene blue (MB) from aqueous solution. Batch adsorption studies were carried out by varying experimental parameters such as solution pH, initial concentration and adsorbent dosage. The optimum pH values for MO and MB removal were pH 2.0 and pH 8.0, respectively. At an initial MO and MB concentration of 20 mg/L, the maximum removal percentage of MO and MB were 18.9 % and 81.3 %, respectively. The adsorption equilibrium data were correlated with both Langmuir and Freundlich isotherm models. The biomass adsorbent was characterised using Field Emission Scanning Electron Microscope (FESEM) and Fourier Transform Infrared Spectrometer (FTIR). Results from this study suggest that lala clam shell, a fishery waste, can be beneficial for water treatment.

Assessing the potential contributions of additional retention processes to PFAS retardation in the subsurface.

PubMed

Brusseau, Mark L

2018-02-01

A comprehensive understanding of the transport and fate of per- and poly-fluoroalkyl substances (PFAS) in the subsurface is critical for accurate risk assessments and design of effective remedial actions. A multi-process retention model is proposed to account for potential additional sources of retardation for PFAS transport in source zones. These include partitioning to the soil atmosphere, adsorption at air-water interfaces, partitioning to trapped organic liquids (NAPL), and adsorption at NAPL-water interfaces. An initial assessment of the relative magnitudes and significance of these retention processes was conducted for two PFAS of primary concern, perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), and an example precursor (fluorotelomer alcohol, FTOH). The illustrative evaluation was conducted using measured porous-medium properties representative of a sandy vadose-zone soil. Data collected from the literature were used to determine measured or estimated values for the relevant distribution coefficients, which were in turn used to calculate retardation factors for the model system. The results showed that adsorption at the air-water interface was a primary source of retention for both PFOA and PFOS, contributing approximately 50% of total retention for the conditions employed. Adsorption to NAPL-water interfaces and partitioning to bulk NAPL were also shown to be significant sources of retention. NAPL partitioning was the predominant source of retention for FTOH, contributing ~98% of total retention. These results indicate that these additional processes may be, in some cases, significant sources of retention for subsurface transport of PFAS. The specific magnitudes and significance of the individual retention processes will depend upon the properties and conditions of the specific system of interest (e.g., PFAS constituent and concentration, porous medium, aqueous chemistry, fluid saturations, co-contaminants). In cases wherein these additional retention processes are significant, retardation of PFAS in source areas would likely be greater than what is typically estimated based on the standard assumption of solid-phase adsorption as the sole retention mechanism. This has significant ramifications for accurate determination of the migration potential and magnitude of mass flux to groundwater, as well as for calculations of contaminant mass residing in source zones. Both of which have critical implications for human-health risk assessments. Copyright © 2017 Elsevier B.V. All rights reserved.

Community Analysis and Recovery of Phenol-degrading Bacteria from Drinking Water Biofilters

PubMed Central

Gu, Qihui; Wu, Qingping; Zhang, Jumei; Guo, Weipeng; Wu, Huiqing; Sun, Ming

2016-01-01

Phenol is a ubiquitous organic contaminant in drinking water. Biodegradation plays an important role in the elimination of phenol pollution in the environment, but the information about phenol removal by drinking water biofilters is still lacking. Herein, we study an acclimated bacterial community that can degrade over 80% of 300 mg/L phenol within 3 days. PCR detection of genotypes involved in bacterial phenol degradation revealed that the degradation pathways contained the initial oxidative attack by phenol hydroxylase, and subsequent ring fission by catechol 1,2-dioxygenase. Based on the PCR denatured gradient gel electrophoresis (PCR-DGGE) profiles of bacteria from biological activated carbon (BAC), the predominant bacteria in drinking water biofilters including Delftia sp., Achromobacter sp., and Agrobacterium sp., which together comprised up to 50% of the total microorganisms. In addition, a shift in bacterial community structure was observed during phenol biodegradation. Furthermore, the most effective phenol-degrading strain DW-1 that correspond to the main band in denaturing gradient gel electrophoresis (DGGE) profile was isolated and identified as Acinetobacter sp., according to phylogenetic analyses of the 16S ribosomal ribonucleic acid (rRNA) gene sequences. The strain DW-1 also produced the most important enzyme, phenol hydroxylase, and it also exhibited a good ability to degrade phenol when immobilized on granular active carbon (GAC). This study indicates that the enrichment culture has great potential application for treatment of phenol-polluted drinking water sources, and the indigenous phenol-degrading microorganism could recover from drinking water biofilters as an efficient resource for phenol removal. Therefore, the aim of this study is to draw attention to recover native phenol-degrading bacteria from drinking water biofilters, and use these native microorganisms as phenolic water remediation in drinking water sources. PMID:27148185

Terrestrial Fe-oxide Concretions and Mars Blueberries: Comparisons of Similar Advective and Diffusive Chemical Infiltration Reaction Mechanisms

NASA Astrophysics Data System (ADS)

Park, A. J.; Chan, M. A.

2006-12-01

Abundant iron oxide concretions occurring in Navajo Sandstone of southern Utah and those discovered at Meridiani Planum, Mars share many common observable physical traits such as their spheriodal shapes, occurrence, and distribution patterns in sediments. Terrestrial concretions are products of interaction between oxygen-rich aquifer water and basin-derived reducing (iron-rich) water. Water-rock interaction simulations show that diffusion of oxygen and iron supplied by slow-moving water is a reasonable mechanism for producing observed concretion patterns. In short, southern Utah iron oxide concretions are results of Liesegang-type diffusive infiltration reactions in sediments. We propose that the formation of blueberry hematite concretions in Mars sediments followed a similar diagenetic mechanism where iron was derived from the alteration of volcanic substrate and oxygen was provided by the early Martian atmosphere. Although the terrestrial analog differs in the original host rock composition, both the terrestrial and Mars iron-oxide precipitation mechanisms utilize iron and oxygen interactions in sedimentary host rock with diffusive infiltration of solutes from two opposite sources. For the terrestrial model, slow advection of iron-rich water is an important factor that allowed pervasive and in places massive precipitation of iron-oxide concretions. In Mars, evaporative flux of water at the top of the sediment column may have produced a slow advective mass-transfer mechanism that provided a steady source and the right quantity of iron. The similarities of the terrestrial and Martian systems are demonstrated using a water-rock interaction simulator Sym.8, initially in one-dimensional systems. Boundary conditions such as oxygen content of water, partial pressure of oxygen, and supply rate of iron were varied. The results demonstrate the importance of slow advection of water and diffusive processes for producing diagenetic iron oxide concretions.

Process Development for Removal of Siloxanes from ISS Atmosphere

NASA Technical Reports Server (NTRS)

Carter, Layne; Perry, Jay; Kayatin, Matthew J.; Wilson, Mark; Gentry, Gregory J.; Bowman, Elizabeth; Monje, Oscar; Rector, Tony; Steele, John

2015-01-01

Dimethylsilanediol (DMSD) has been identified as a problematic organic contaminant aboard the ISS. This contaminant was initially identified in humidity condensate and in the Water Processor Assembly (WPA) product water in 2010 when routine water quality monitoring an increasing total organic carbon (TOC) trend in the WPA product water. Although DMSD is not a crew health hazard at the levels observed in the product water, it can degrade the WPA catalytic reactor's effectiveness and cause early replacement of Multifiltration Beds. DMSD may also degrade the performance of the Oxygen Generation System (OGS) which uses the WPA product water for electrolysis. An investigation into the source of DMSD has determined that polydimethylsiloxane (PDMS) compounds are likely hydrolyzing in the Condensing Heat Exchangers (CHX) to form DMSD. PDMS compounds are prevalent aboard ISS from a variety of sources, including crew hygiene products, adhesives, caulks, lubricants, and various nonmetallic materials. PDMS compounds are also known to contribute to CHX hydrophilic coating degradation by rendering it hydrophobic and therefore adversely affecting its ability to effectively transmit water to the condensate bus. Eventually this loss in performance results in water droplets in the air flow exiting the CHX, which may lead to microbial growth in the air ducts and may impact the performance of downstream systems. Several options have been evaluated to address these concerns. Modifications to the Water Processor Multifiltration Beds and Catalytic Reactor for removal of DMSD were not considered viable, and did not address the issue with PDMS compound degradation of the CHX coating. Design concepts are now in development for removing PDMS compounds from the air stream before they can reach the CHX coating, thus preventing coating degradation and hydrolysis of the PDMS compounds to DMSD. This paper summarizes the current status of the effort to treat these contaminants on ISS.

A new method for water desalination using microbial desalination cells.

PubMed

Cao, Xiaoxin; Huang, Xia; Liang, Peng; Xiao, Kang; Zhou, Yingjun; Zhang, Xiaoyuan; Logan, Bruce E

2009-09-15

Current water desalination techniques are energy intensive and some use membranes operated at high pressures. It is shown here that water desalination can be accomplished without electrical energy input or high water pressure by using a source of organic matter as the fuel to desalinate water. A microbial fuel cell was modified by placing two membranes between the anode and cathode, creating a middle chamber for water desalination between the membranes. An anion exchange membrane was placed adjacent to the anode, and a cation exchange membrane was positioned next to the cathode. When current was produced by bacteria on the anode, ionic species in the middle chamber were transferred into the two electrode chambers, desalinating the water in the middle chamber. Proof-of-concept experiments for this approach, using what we call a microbial desalination cell (MDC), was demonstrated using water at different initial salt concentrations (5, 20, and 35 g/L) with acetate used as the substrate for the bacteria. The MDC produced a maximum of 2 W/m2 (31 W/m3) while at the same time removing about 90% of the salt in a single desalination cycle. As the salt was removed from the middle chamber the ohmic resistance of the MDC (measured using electrochemical impedance spectroscopy) increased from 25 Omega to 970 Omega at the end of the cycle. This increased resistance was reflected by a continuous decrease in the voltage produced over the cycle. These results demonstrate for the first time the possibility for a new method for water desalination and power production that uses only a source of biodegradable organic matter and bacteria.

Community Analysis and Recovery of Phenol-degrading Bacteria from Drinking Water Biofilters.

PubMed

Gu, Qihui; Wu, Qingping; Zhang, Jumei; Guo, Weipeng; Wu, Huiqing; Sun, Ming

2016-01-01

Phenol is a ubiquitous organic contaminant in drinking water. Biodegradation plays an important role in the elimination of phenol pollution in the environment, but the information about phenol removal by drinking water biofilters is still lacking. Herein, we study an acclimated bacterial community that can degrade over 80% of 300 mg/L phenol within 3 days. PCR detection of genotypes involved in bacterial phenol degradation revealed that the degradation pathways contained the initial oxidative attack by phenol hydroxylase, and subsequent ring fission by catechol 1,2-dioxygenase. Based on the PCR denatured gradient gel electrophoresis (PCR-DGGE) profiles of bacteria from biological activated carbon (BAC), the predominant bacteria in drinking water biofilters including Delftia sp., Achromobacter sp., and Agrobacterium sp., which together comprised up to 50% of the total microorganisms. In addition, a shift in bacterial community structure was observed during phenol biodegradation. Furthermore, the most effective phenol-degrading strain DW-1 that correspond to the main band in denaturing gradient gel electrophoresis (DGGE) profile was isolated and identified as Acinetobacter sp., according to phylogenetic analyses of the 16S ribosomal ribonucleic acid (rRNA) gene sequences. The strain DW-1 also produced the most important enzyme, phenol hydroxylase, and it also exhibited a good ability to degrade phenol when immobilized on granular active carbon (GAC). This study indicates that the enrichment culture has great potential application for treatment of phenol-polluted drinking water sources, and the indigenous phenol-degrading microorganism could recover from drinking water biofilters as an efficient resource for phenol removal. Therefore, the aim of this study is to draw attention to recover native phenol-degrading bacteria from drinking water biofilters, and use these native microorganisms as phenolic water remediation in drinking water sources.

Absence of Mycobacterium intracellulare and presence of Mycobacterium chimaera in household water and biofilm samples of patients in the United States with Mycobacterium avium complex respiratory disease.

PubMed

Wallace, Richard J; Iakhiaeva, Elena; Williams, Myra D; Brown-Elliott, Barbara A; Vasireddy, Sruthi; Vasireddy, Ravikiran; Lande, Leah; Peterson, Donald D; Sawicki, Janet; Kwait, Rebecca; Tichenor, Wellington S; Turenne, Christine; Falkinham, Joseph O

2013-06-01

Recent studies have shown that respiratory isolates from pulmonary disease patients and household water/biofilm isolates of Mycobacterium avium could be matched by DNA fingerprinting. To determine if this is true for Mycobacterium intracellulare, household water sources for 36 patients with Mycobacterium avium complex (MAC) lung disease were evaluated. MAC household water isolates from three published studies that included 37 additional MAC respiratory disease patients were also evaluated. Species identification was done initially using nonsequencing methods with confirmation by internal transcribed spacer (ITS) and/or partial 16S rRNA gene sequencing. M. intracellulare was identified by nonsequencing methods in 54 respiratory cultures and 41 household water/biofilm samples. By ITS sequencing, 49 (90.7%) respiratory isolates were M. intracellulare and 4 (7.4%) were Mycobacterium chimaera. In contrast, 30 (73%) household water samples were M. chimaera, 8 (20%) were other MAC X species (i.e., isolates positive with a MAC probe but negative with species-specific M. avium and M. intracellulare probes), and 3 (7%) were M. avium; none were M. intracellulare. In comparison, M. avium was recovered from 141 water/biofilm samples. These results indicate that M. intracellulare lung disease in the United States is acquired from environmental sources other than household water. Nonsequencing methods for identification of nontuberculous mycobacteria (including those of the MAC) might fail to distinguish closely related species (such as M. intracellulare and M. chimaera). This is the first report of M. chimaera recovery from household water. The study underscores the importance of taxonomy and distinguishing the many species and subspecies of the MAC.

Innovative Tools for Water Quality/Quantity Management: New York City's Operations Support Tool

NASA Astrophysics Data System (ADS)

Wang, L.; Schaake, J. C.; Day, G. N.; Porter, J.; Sheer, D. P.; Pyke, G.

2011-12-01

The New York City Department of Environmental Protection (DEP) manages New York City's water supply, which is comprised of over 20 reservoirs and supplies more than 1 billion gallons of water per day to over 9 million customers. Recently, DEP has initiated design of an Operations Support Tool (OST), a state-of-the-art decision support system to provide computational and predictive support for water supply operations and planning. This presentation describes the technical structure of OST, including the underlying water supply and water quality models, data sources and database management, reservoir inflow forecasts, and the functionalities required to meet the needs of a diverse group of end users. OST is a major upgrade of DEP's current water supply - water quality model, developed to evaluate alternatives for controlling turbidity in NYC's Catskill reservoirs. While the current model relies on historical hydrologic and meteorological data, OST can be driven by forecasted future conditions. It will receive a variety of near-real-time data from a number of sources. OST will support two major types of simulations: long-term, for evaluating policy or infrastructure changes over an extended period of time; and short-term "position analysis" (PA) simulations, consisting of multiple short simulations, all starting from the same initial conditions. Typically, the starting conditions for a PA run will represent those for the current day and traces of forecasted hydrology will drive the model for the duration of the simulation period. The result of these simulations will be a distribution of future system states based on system operating rules and the range of input ensemble streamflow predictions. DEP managers will analyze the output distributions and make operation decisions using risk-based metrics such as probability of refill. Currently, in the developmental stages of OST, forecasts are based on antecedent hydrologic conditions and are statistical in nature. The statistical algorithm is a relatively simple and versatile, but lacks short-term skill critical for water quality and spill management. To improve short-term skill, OST will ultimately operate with meteorologically driven hydrologic forecasts provided by the National Weather Service (NWS). OST functionalities will support a wide range of DEP uses, including short term operational projections, outage planning and emergency management, operating rule development, and water supply planning. A core use of OST will be to inform reservoir management strategies to control and mitigate turbidity events while ensuring water supply reliability. OST will also allow DEP to manage its complex reservoir system to meet multiple objectives, including ecological flows, tailwater fisheries and recreational releases, and peak flow mitigation for downstream communities.

The GreenLab Research Facility: A Micro-Grid Integrating Production, Consumption and Storage of Clean Energy

NASA Technical Reports Server (NTRS)

McDowell Bomani, Bilal Mark; Elbuluk, Malik; Fain, Henry; Kankam, Mark D.

2012-01-01

There is a large gap between the production and demand for energy from alternative fuel and alternative renewable energy sources. The NASA Glenn Research Center (GRC) has initiated a laboratory-pilot study that concentrates on using biofuels as viable alternative fuel resources for the field of aviation, as well as, utilizing wind and solar technologies as alternative renewable energy resources, and in addition, the use of pumped water for storage of energy that can be retrieved through hydroelectric generation. This paper describes the GreenLab Research Facility and its power and energy sources with .recommendations for worldwide expansion and adoption of the concept of such a facility

Failure and life cycle evaluation of watering valves.

PubMed

Gonzalez, David M; Graciano, Sandy J; Karlstad, John; Leblanc, Mathias; Clark, Tom; Holmes, Scott; Reuter, Jon D

2011-09-01

Automated watering systems provide a reliable source of ad libitum water to animal cages. Our facility uses an automated water delivery system to support approximately 95% of the housed population (approximately 14,000 mouse cages). Drinking valve failure rates from 2002 through 2006 never exceeded the manufacturer standard of 0.1% total failure, based on monthly cage census and the number of floods. In 2007, we noted an increase in both flooding and cases of clinical dehydration in our mouse population. Using manufacturer's specifications for a water flow rate of 25 to 50 mL/min, we initiated a wide-scale screening of all valves used. During a 4-mo period, approximately 17,000 valves were assessed, of which 2200 failed according to scoring criteria (12.9% overall; 7.2% low flow; 1.6% no flow; 4.1% leaky). Factors leading to valve failures included residual metal shavings, silicone flash, introduced debris or bedding, and (most common) distortion of the autoclave-rated internal diaphragm and O-ring. Further evaluation revealed that despite normal autoclave conditions of heat, pressure, and steam, an extreme negative vacuum pull caused the valves' internal silicone components (diaphragm and O-ring) to become distorted and water-permeable. Normal flow rate often returned after a 'drying out' period, but components then reabsorbed water while on the animal rack or during subsequent autoclave cycles to revert to a variable flow condition. On the basis of our findings, we recalibrated autoclaves and initiated a preventative maintenance program to mitigate the risk of future valve failure.

Failure and Life Cycle Evaluation of Watering Valves

PubMed Central

Gonzalez, David M; Graciano, Sandy J; Karlstad, John; Leblanc, Mathias; Clark, Tom; Holmes, Scott; Reuter, Jon D

2011-01-01

Automated watering systems provide a reliable source of ad libitum water to animal cages. Our facility uses an automated water delivery system to support approximately 95% of the housed population (approximately 14,000 mouse cages). Drinking valve failure rates from 2002 through 2006 never exceeded the manufacturer standard of 0.1% total failure, based on monthly cage census and the number of floods. In 2007, we noted an increase in both flooding and cases of clinical dehydration in our mouse population. Using manufacturer's specifications for a water flow rate of 25 to 50 mL/min, we initiated a wide-scale screening of all valves used. During a 4-mo period, approximately 17,000 valves were assessed, of which 2200 failed according to scoring criteria (12.9% overall; 7.2% low flow; 1.6% no flow; 4.1% leaky). Factors leading to valve failures included residual metal shavings, silicone flash, introduced debris or bedding, and (most common) distortion of the autoclave-rated internal diaphragm and O-ring. Further evaluation revealed that despite normal autoclave conditions of heat, pressure, and steam, an extreme negative vacuum pull caused the valves’ internal silicone components (diaphragm and O-ring) to become distorted and water-permeable. Normal flow rate often returned after a ‘drying out’ period, but components then reabsorbed water while on the animal rack or during subsequent autoclave cycles to revert to a variable flow condition. On the basis of our findings, we recalibrated autoclaves and initiated a preventative maintenance program to mitigate the risk of future valve failure. PMID:22330720

Waterless Clothes-Cleaning Machine

NASA Technical Reports Server (NTRS)

Johnson, Glenn; Ganske, Shane

2013-01-01

A waterless clothes-cleaning machine has been developed that removes loose particulates and deodorizes dirty laundry with regenerative chemical processes to make the clothes more comfortable to wear and have a fresher smell. This system was initially developed for use in zero-g, but could be altered for 1-g environments where water or other re sources are scarce. Some of these processes include, but are not limited to, airflow, filtration, ozone generation, heat, ultraviolet light, and photocatalytic titanium oxide.

Spin Coherence in Silicon-based Quantum Structures and Devices

DTIC Science & Technology

2017-08-31

Using electron spin resonance (ESR) to measure the den- sity of shallow traps, we find that the two sets of devices are nearly identical , indicating...experiments which cannot utilize a clock transition or a field-cancelling decoherence-free subspace. Our approach was to lock the microwave source driving...the electron spins to a strong nuclear spin signal. In our initial experiments we locked to the proton signal in a water cell. However, the noise in

Prebiotic chemistry: chemical evolution of organics on the primitive Earth under simulated prebiotic conditions.

PubMed

Dondi, Daniele; Merli, Daniele; Pretali, Luca; Fagnoni, Maurizio; Albini, Angelo; Serpone, Nick

2007-11-01

A series of prebiotic mixtures of simple molecules, sources of C, H, N, and O, were examined under conditions that may have prevailed during the Hadean eon (4.6-3.8 billion years), namely an oxygen-free atmosphere and a significant UV radiation flux over a large wavelength range due to the absence of an ozone layer. Mixtures contained a C source (methanol, acetone or other ketones), a N source (ammonia or methylamine), and an O source (water) at various molar ratios of C : H : N : O. When subjected to UV light or heated for periods of 7 to 45 days under an argon atmosphere, they yielded a narrow product distribution of a few principal compounds. Different initial conditions produced different distributions. The nature of the products was ascertained by gas chromatographic-mass spectral analysis (GC-MS). UVC irradiation of an aqueous methanol-ammonia-water prebiotic mixture for 14 days under low UV dose (6 x 10(-2) Einstein) produced methylisourea, hexamethylenetetramine (HMT), methyl-HMT and hydroxy-HMT, whereas under high UV dose (45 days; 1.9 x 10(-1) Einstein) yielded only HMT. By contrast, the prebiotic mixture composed of acetone-ammonia-water produced five principal species with acetamide as the major component; thermally the same mixture produced a different product distribution of four principal species. UVC irradiation of the CH(3)CN-NH(3)-H(2)O prebiotic mixture for 7 days gave mostly trimethyl-s-triazine, whereas in the presence of two metal oxides (TiO(2) or Fe(2)O(3)) also produced some HMT; the thermal process yielded only acetamide.

40 CFR 63.1191 - What notifications must I submit?

Code of Federal Regulations, 2011 CFR

2011-07-01

... becomes a major source. (2) A source that has an initial startup before the effective date of the standard. (3) A new or reconstructed source that has an initial startup after the effective date of the... major source or reconstruct a major source where the initial startup of the new or reconstructed source...

40 CFR 63.1191 - What notifications must I submit?

Code of Federal Regulations, 2013 CFR

2013-07-01

... becomes a major source. (2) A source that has an initial startup before the effective date of the standard. (3) A new or reconstructed source that has an initial startup after the effective date of the... major source or reconstruct a major source where the initial startup of the new or reconstructed source...

40 CFR 63.1191 - What notifications must I submit?

Code of Federal Regulations, 2012 CFR

2012-07-01

... becomes a major source. (2) A source that has an initial startup before the effective date of the standard. (3) A new or reconstructed source that has an initial startup after the effective date of the... major source or reconstruct a major source where the initial startup of the new or reconstructed source...

Microbial and metal water quality in rain catchments compared with traditional drinking water sources in the East Sepik Province, Papua New Guinea.

PubMed

Horak, Helena M; Chynoweth, Joshua S; Myers, Ward P; Davis, Jennifer; Fendorf, Scott; Boehm, Alexandria B

2010-03-01

In Papua New Guinea, a significant portion of morbidity and mortality is attributed to water-borne diseases. To reduce incidence of disease, communities and non-governmental organizations have installed rain catchments to provide drinking water of improved quality. However, little work has been done to determine whether these rain catchments provide drinking water of better quality than traditional drinking water sources, and if morbidity is decreased in villages with rain catchments. The specific aim of this study was to evaluate the quality of water produced by rain catchments in comparison with traditional drinking water sources in rural villages in the East Sepik Province. Fifty-four water sources in 22 villages were evaluated for enterococci and Escherichia coli densities as well as 14 health-relevant metals. In addition, we examined how the prevalence of diarrhoeal illness in villages relates to the type of primary drinking water source. The majority of tested metals were below World Health Organization safety limits. Catchment water sources had lower enterococci and E. coli than other water sources. Individuals in villages using Sepik River water as their primary water source had significantly higher incidence of diarrhoea than those primarily using other water sources (streams, dug wells and catchments).

Plant Assimilation Kinetics and Metabolism of 2-Mercaptobenzothiazole Tire Rubber Vulcanizers by Arabidopsis.

PubMed

LeFevre, Gregory H; Portmann, Andrea C; Müller, Claudia E; Sattely, Elizabeth S; Luthy, Richard G

2016-07-05

2-Mercaptobenzothiazole (MBT) is a tire rubber vulcanizer found in potential sources of reclaimed water where it may come in contact with vegetation. In this work, we quantified the plant assimilation kinetics of MBT using Arabidopsis under hydroponic conditions. MBT depletion kinetics in the hydroponic medium with plants were second order (t1/2 = 0.52 to 2.4 h) and significantly greater than any abiotic losses (>18 times faster; p = 0.0056). MBT depletion rate was related to the initial exposure concentration with higher rates at greater concentrations from 1.6 μg/L to 147 μg/L until a potentially inhibitory level (1973 μg/L) lowered the assimilation rate. 9.8% of the initial MBT mass spike was present in the plants after 3 h and decreased through time. In-source LC-MS/MS fragmentation revealed that MBT was converted by Arabidopsis seedlings to multiple conjugated-MBT metabolites of differential polarity that accumulate in both the plant tissue and hydroponic medium; metabolite representation evolved temporally. Multiple novel MBT-derived plant metabolites were detected via LC-QTOF-MS analysis; proposed transformation products include glucose and amino acid conjugated MBT metabolites. Elucidating plant transformation products of trace organic contaminants has broad implications for water reuse because plant assimilation could be employed advantageously in engineered natural treatment systems, and plant metabolites in food crops could present an unintended exposure route to consumers.

Groundwater quality in an abandoned metal extraction site: the case study of Campello Monti (NW Italy)

NASA Astrophysics Data System (ADS)

Mehta, Neha; Lasagna, Manuela; Antonella Dino, Giovanna; De Luca, Domenico Antonio

2017-04-01

Extractive activities present threat to natural water systems and their effects are observed even after the cessation of activities. The harmful effects of extractive activities such as deterioration of water sources by low quality waters or by allowing leaching of metals into groundwater makes it necessary to carry out careful, scientific and comprehensive studies on this subject. Consequently, the same problem statement was chosen as part of a PhD research Project. The PhD research is part of REMEDIATE project (A Marie Sklodowska-Curie Action Initial Training Network for Improved decision making in contaminated land site investigation and risk assessment, Grant Agreement No. 643087). The current work thus points out on the contamination of groundwater sources due to past mining activities in the area. Contaminated groundwater may act as possible contamination source to surface water also. The impacts on water systems connected to mining activities depend on the ore type, metal being extracted, exploitation method, ore processing, pollution control efforts, geochemical and hydrogeochemical conditions of water and surroundings. To evaluate the effects posed by past metal extracting activities the study was carried out at an abandoned site used for extracting nickel in Campello Monti (Valstrona municipality, Piedmont region, Italy). Campello Monti is located in basement of Southern Italian Alps in the Ivrea Verbano Zone. The area is composed of mafic rocks intruded by mantle periodite. The mafic formation consists of peridotites, pyroxenites, gabbros, anorthosites, gabbro-norite, gabbro-diorite and diorite. Mines were used for nickel exploitation from 9th Century and continued until 1940s. The long history of nickel extraction has left the waste contaminated with Ni and Co in the mountains alongwith tunnels used for carrying out metal extracting activities. The area around the site is used for housing, shows the presence of domestic animals and has Strona creek passing through it. The groundwater circulation takes place in fractured rocks, in waste dumps and tunnels used for extracting metal. Thus the abandoned site may contaminate local water sources. To study the impacts on local water sources, water sampling and analysis were performed. Three sampling campaigns in June, July and October 2016 resulted in 16 groundwater samples (4 tap water samples, 3 samples from tunnels and 9 from springs) and 6 surface water samples. The samples were analyzed to measure alkalinity, electrolytic conductivity, pH , temperature, metals such as- Hg, Tl, Cd, Cr (total), Cr (VI), Ag, As ,Pb , Se, Ni, Co, Mn, Al, Fe, Cu, Zn, B and metal ions -CN-, Fl-, Mg2+, Na+, SO42-, NO3- ,Cl-. The water samples collected from tunnels showed nickel concentration ranging from 31.9 µg/ l to as high as 304 µg/ l (permissible limit for Ni in Italy according to DLgs. 152/06 is 20 µg/l ). These groundwaters, being in close association with minerals containing heavy metals tend to dissolve such elements. The springs in mountains also contained Ni higher than 20 µg/l. These all groundwater systems act as source to Strona creek which showed Ni concentration of 512 µg/l.

Efficient catalytic ozonation of bisphenol-A over reduced graphene oxide modified sea urchin-like α-MnO(2) architectures.

PubMed

Li, Gang; Lu, Yongtao; Lu, Cheng; Zhu, Mingshan; Zhai, Chunyang; Du, Yukou; Yang, Ping

2015-08-30

Considering the biological deleterious effect of bisphenol-A (BPA) in water to the human beings, great efforts have been made for the elimination of this contaminant from water sources. Herein, we report a novel nanocomposite composed of three-dimensional (3D) sea urchin-like α-MnO2 nanoarchitectures and reduced graphene oxide (RGO) for the elimination of BPA in water in the presence of ozone. The synthesis of the as-prepared nanocomposite is facile, and the nanocomposites were well characterized by SEM, TEM, XRD, and Raman spectra. The as-synthesized α-MnO2/RGO nanocomposite was found to be a highly efficient catalyst to eliminate BPA from water in the presence of ozone. The intermediates of ozonzation were also detected by gas chromatography-mass spectrometry (GC-MS). Our investigation initiates a new opportunity to explore the high-performance catalysts for the removal of the organic pollutions in water. Copyright © 2015 Elsevier B.V. All rights reserved.

The interaction between nitrobenzene and Microcystis aeruginosa and its potential to impact water quality.

PubMed

Liu, Zhiquan; Cui, Fuyi; Ma, Hua; Fan, Zhenqiang; Zhao, Zhiwei; Hou, Zhenling; Liu, Dongmei; Jia, Xuebin

2013-08-01

The potential water quality problems caused by the interaction between nitrobezene (NB) and Microcystis aeruginosa was investigated by studying the growth inhibition, the haloacetic acids formation potential (HAAFP) and the secretion of microcystin-LR (MC-LR). The results showed that NB can inhibit the growth of M. aeruginosa, and the value of EC50 increased with the increase of initial algal density. Although NB can hardly react with chlorine to form HAAs, the presence of NB can enhance the HAAFP productivity. The secretion of the intracellular MC-LR is constant under the steady experimental conditions. However, the presence of NB can reduce the MC-LR productivity of M. aeruginosa. Overall, the increased disinfection risk caused by the interaction has more important effect on the safety of drinking water quality than the benefit of the decreased MC-LR productivity, and should be serious considered when the water contained NB and M. aeruginosa is used as drinking water source. Copyright © 2013 Elsevier Ltd. All rights reserved.

Direct Detection of Pharmaceuticals and Personal Care Products from Aqueous Samples with Thermally-Assisted Desorption Electrospray Ionization Mass Spectrometry

NASA Astrophysics Data System (ADS)

Campbell, Ian S.; Ton, Alain T.; Mulligan, Christopher C.

2011-07-01

An ambient mass spectrometric method based on desorption electrospray ionization (DESI) has been developed to allow rapid, direct analysis of contaminated water samples, and the technique was evaluated through analysis of a wide array of pharmaceutical and personal care product (PPCP) contaminants. Incorporating direct infusion of aqueous sample and thermal assistance into the source design has allowed low ppt detection limits for the target analytes in drinking water matrices. With this methodology, mass spectral information can be collected in less than 1 min, consuming ~100 μL of total sample. Quantitative ability was also demonstrated without the use of an internal standard, yielding decent linearity and reproducibility. Initial results suggest that this source configuration is resistant to carryover effects and robust towards multi-component samples. The rapid, continuous analysis afforded by this method offers advantages in terms of sample analysis time and throughput over traditional hyphenated mass spectrometric techniques.

Direct detection of pharmaceuticals and personal care products from aqueous samples with thermally-assisted desorption electrospray ionization mass spectrometry.

PubMed

Campbell, Ian S; Ton, Alain T; Mulligan, Christopher C

2011-07-01

An ambient mass spectrometric method based on desorption electrospray ionization (DESI) has been developed to allow rapid, direct analysis of contaminated water samples, and the technique was evaluated through analysis of a wide array of pharmaceutical and personal care product (PPCP) contaminants. Incorporating direct infusion of aqueous sample and thermal assistance into the source design has allowed low ppt detection limits for the target analytes in drinking water matrices. With this methodology, mass spectral information can be collected in less than 1 min, consuming ~100 μL of total sample. Quantitative ability was also demonstrated without the use of an internal standard, yielding decent linearity and reproducibility. Initial results suggest that this source configuration is resistant to carryover effects and robust towards multi-component samples. The rapid, continuous analysis afforded by this method offers advantages in terms of sample analysis time and throughput over traditional hyphenated mass spectrometric techniques.

A closed life-support system for space colonies

NASA Technical Reports Server (NTRS)

Johnson, R. D.; Jebens, H. J.; Sweet, H. C.

1977-01-01

In 1975, a system design study was performed to examine a completely self-contained system for a permanent colony of 10,000 inhabitants in space. Fundamental to this design was the life support system. Since resupply from earth is prohibitive in transportation costs, it was decided to use a closed system with the initial supply of oxygen coming from processing of lunar ores, and the supply of carbon, nitrogen and hydrogen from earth. The problem of life support was treated starting with the nutritional and metabolic requirements for the human population, creating a food and water chain sufficient to supply these demands, adding the additional requirements for the animal and plant sources in the food chain, feeding back useful waste products, supplying water as required from different sources, and closing the loop by processing organic wastes into CO2. This concept places the burden of the system upon plants for O2 generation and waste processing the CO2 generation.

Research on Coupling Method of Watershed Initial Water Rights Allocation in Daling River

NASA Astrophysics Data System (ADS)

Liu, J.; Fengping, W.

2016-12-01

Water scarcity is now a common occurrence in many countries. The situation of watershed initial water rights allocation has caused many benefit conflicts among regions and regional water sectors of domestic and ecology environment and industries in China. This study aims to investigate the method of watershed initial water rights allocation in the perspective of coupling in Daling River Watershed taking provincial initial water rights and watershed-level governmental reserved water as objects. First of all, regarding the allocation subsystem of initial water rights among provinces, this research calculates initial water rights of different provinces by establishing the coupling model of water quantity and quality on the principle of "rewarding efficiency and penalizing inefficiency" based on the two control objectives of water quantity and quality. Secondly, regarding the allocation subsystem of watershed-level governmental reserved water rights, the study forecasts the demand of watershed-level governmental reserved water rights by the combination of case-based reasoning and water supply quotas. Then, the bilaterally coupled allocation model on water supply and demand is designed after supply analysis to get watershed-level governmental reserved water rights. The results of research method applied to Daling River Watershed reveal the recommended scheme of watershed initial water rights allocation based on coordinated degree criterion. It's found that the feasibility of the iteration coupling model and put forward related policies and suggestions. This study owns the advantages of complying with watershed initial water rights allocation mechanism and meeting the control requirements of water quantity, water quality and water utilization efficiency, which help to achieve the effective allocation of water resources.

Tracing the origin of the oxygen-consuming organic matter in the hypoxic zone in a large eutrophic estuary: the lower reach of the Pearl River Estuary, China

NASA Astrophysics Data System (ADS)

Su, Jianzhong; Dai, Minhan; He, Biyan; Wang, Lifang; Gan, Jianping; Guo, Xianghui; Zhao, Huade; Yu, Fengling

2017-09-01

We assess the relative contributions of different sources of organic matter, marine vs. terrestrial, to oxygen consumption in an emerging hypoxic zone in the lower Pearl River Estuary (PRE), a large eutrophic estuary located in Southern China. Our cruise, conducted in July 2014, consisted of two legs before and after the passing of Typhoon Rammasun, which completely de-stratified the water column. The stratification recovered rapidly, within 1 day after the typhoon. We observed algal blooms in the upper layer of the water column and hypoxia underneath in bottom water during both legs. Repeat sampling at the initial hypoxic station showed severe oxygen depletion down to 30 µmol kg-1 before the typhoon and a clear drawdown of dissolved oxygen after the typhoon. Based on a three endmember mixing model and the mass balance of dissolved inorganic carbon and its isotopic composition, the δ13C of organic carbon remineralized in the hypoxic zone was -23.2 ± 1.1 ‰. We estimated that 65 ± 16 % of the oxygen-consuming organic matter was derived from marine sources, and the rest (35 ± 16 %) was derived from the continent. In contrast to a recently studied hypoxic zone in the East China Sea off the Changjiang Estuary where marine organic matter dominated oxygen consumption, here terrestrial organic matter significantly contributed to the formation and maintenance of hypoxia. How varying amounts of these organic matter sources drive oxygen consumption has important implications for better understanding hypoxia and its mitigation in bottom waters.

Mycobacterium chimaera in heater-cooler units used during cardiac surgery - growth and decontamination.

PubMed

Bengtsson, Daniel; Westerberg, Martin; Nielsen, Susanne; Ridell, Malin; Jönsson, Bodil

2018-04-24

Previous studies have identified patients infected with Mycobacterium chimaera (M. chimaera) subsequent to cardiac surgery. Water tanks in heater-cooler units (HCUs) used cardiac heart surgery was traced as source. The aim was to investigate occurrence of M. chimaera and other microorganisms in HCUs and evaluate the silver-ion cleaning routine. Five HCUs were disinfected with silver-ions and examined for mycobacteria directly (15 min) after the disinfection procedures and later on three occasions (3, 6, 10 weeks). One HCU was selected for additional investigation of the presence of other microorganisms. In addition, tap water from five sinks in the surgical department was examined for the presence of mycobacteria and other microorganisms. M. chimaera grew in all the HCU water tanks and in 35 of the 40 HCU samples. Three of the samples also contained Mycobacterium gordonae. When the selected HCU tanks were analysed directly after the disinfection procedure bacteria and fungi were found but no non-fermenting Gram-negative rods. These HCU samples contained a doubled to 3 fold amount of bacteria compared to initial tap water samples. No mycobacteria were found in any sample from the five water taps. The silver-ion cleaning routine was insufficient and M. chimaera was found in all HCUs. However, no mycobacteria were found in any sample from the five water taps suggesting another source of colonization. It is probable that residual water and biofilm are of importance. Our results emphasize the need for improved disinfection procedures and improved construction of the HCUs.

Health Risk Assessment of Cyanobacterial (Blue-green Algal) Toxins in Drinking Water

PubMed Central

Falconer, Ian R.; Humpage, Andrew R.

2005-01-01

Cyanobacterial toxins have caused human poisoning in the Americas, Europe and Australia. There is accumulating evidence that they are present in treated drinking water supplies when cyanobacterial blooms occur in source waters. With increased population pressure and depleted groundwater reserves, surface water is becoming more used as a raw water source, both from rivers and lakes/reservoirs. Additional nutrients in water which arise from sewage discharge, agricultural run-off or storm water result in overabundance of cyanobacteria, described as a ‘water bloom’. The majority of cyanobacterial water-blooms are of toxic species, producing a diversity of toxins. The most important toxins presenting a risk to the human population are the neurotoxic alkaloids (anatoxins and paralytic shellfish poisons), the cyclic peptide hepatotoxins (microcystins) and the cytotoxic alkaloids (cylindrospermopsins). At the present time the only cyanobacteral toxin family that have been internationally assessed for health risk by the WHO are the microcystins, which cause acute liver injury and are active tumour promoters. Based on sub-chronic studies in rodents and pigs, a provisional Guideline Level for drinking water of 1μg/L of microcystin-LR has been determined. This has been adopted in legislation in countries in Europe, South America and Australasia. This may be revised in the light of future teratogenicity, reproductive toxicity and carcinogenicity studies. The other cyanobacterial toxin which has been proposed for detailed health risk assessment is cylindrospermopsin, a cytotoxic compound which has marked genotoxicity, probable mutagenicity, and is a potential carcinogen. This toxin has caused human poisoning from drinking water, and occurs in water supplies in the USA, Europe, Asia, Australia and South America. An initial health risk assessment is presented with a proposed drinking water Guideline Level of 1μg/L. There is a need for both increased monitoring data for toxins in drinking water and epidemiological studies on adverse health effects in exposed populations to clarify the extent of the health risk. PMID:16705800

Redox conditions and the efficiency of chlorinated ethene biodegradation: Field studies

USGS Publications Warehouse

Chapelle, F.H.; Bradley, P.M.

2000-01-01

The effect of redox conditions on the efficiency of chlorinated ethene biodegradation was investigated at two field sites. One site (NAS Cecil Field, FL) is characterized by predominantly Fe(III)-reducing conditions in the contaminant source area, grading to predominantly sulfate- reducing conditions downgradient. This sequence of redox conditions led to relatively inefficient biodegradation of chlorinated ethenes, with high concentrations of trichloroethene extending more than 400 meters downgradient of the source area. In contrast, a second site (NBS Kings Bay, GA) characterized by predominantly sulfate-reducing conditions in the source area followed by Fe(III)-reducing conditions downgradient. In this system perchloroethene (PCE) and TCE were rapidly biodegraded and extended less than 100 meters downgradient. Rates of ground- water transport are similar at the two sites (???0.2 m/d) indicating that the succession of redox processes, rather than other hydrologic factors, is the principal control on biodegradation. In particular, redox conditions that favor the initial reduction of highly chlorinated ethenes (methanogenic or sulfate-reducing conditions) followed by more oxidizing conditions (Fe(III)- reducing or oxic conditions) favors efficient biodegradation. Thus, documenting the succession of redox processes is an important step in understanding the efficiency of chlorinated ethene biodegradation in ground-water systems.

Scope for solar hydrogen power plants along Indian coasts

NASA Astrophysics Data System (ADS)

Hajra, Debdyut; Mukhopadhyay, Swarnav

2016-09-01

Energy is at the core of economic growth and development in the present day world. But relentless and unchecked use of harmful energy resources like fossil fuels (coil and oil), nuclear energy has taken a toll on mother nature. The energy coffers are being rapidly depleted and within a few years all of them will become empty, leaving nothing for the future generations to build on. Their constant usage has degraded the air quality and given way to land and water pollution. Scientists and world leaders have initiated a call for action to shift our dependence from currently popular energy sources to cleaner and renewable energy sources. Search for such energy sources have been going on for many years. Solar energy, wind energy, ocean energy, tidal energy, biofuel, etc. have caught the attention of people. Another such important which has become popular is 'Solar Hydrogen'. Many visionary scientists have called hydrogen the energy of the future. It is produced from water by direct or indirect use of sunlight in a sustainable manner. This paper discusses the current energy scenario, the importance of solar-hydrogen as a fuel and most importantly the scope for solar hydrogen power plants along Indian coastline.

Impact of environmental policies on the adoption of manure management practices in the Chesapeake Bay watershed.

PubMed

Savage, Jeff A; Ribaudo, Marc O

2013-11-15

Pollution in the Chesapeake Bay is a problem and has been a focus of federal and state initiatives to reduce nutrient pollution from agriculture and other sources since 1983. In 2010 EPA established a TMDL for the watershed. Producers may voluntarily respond to intense and focused policy scrutiny by adopting best management practices. A detailed analysis of water quality best management practices by animal feeding operations inside and outside the watershed yield insight into this relationship. Our findings support the hypothesis that farmers will adopt water quality measures if links are made clear and there is an expectation of future regulations. Published by Elsevier Ltd.

The influence of H2O line blanketing on the spectra of cool dwarf stars

NASA Technical Reports Server (NTRS)

Allard, F.; Hauschildt, P. H.; Miller, S.; Tennyson, J.

1994-01-01

We present our initial results of model atmosphere calculations for cool M dwarfs using an opacity sampling method and a new list of H2O lines. We obtain significantly improved fits to the infrared spectrum of the M dwarf VB10 when compared to earlier models. H2O is by far the dominant opacity source in cool stars. To illustrate this, we show the Rosseland mean of the total extinction under various assumptions. Our calculations demonstrate the importance of a good treatment of the water opacities in cool stars and the improvements possible by using up-to-date data for the water line absorption.

New method to determine initial surface water displacement at tsunami source

NASA Astrophysics Data System (ADS)

Lavrentyev, Mikhail; Romanenko, Alexey; Tatarintsev, Pavel

2013-04-01

Friday, March 11, 2011 at 05:46:23 UTC, Japan was struck by an 8.9-magnitude earthquake near its Northeastern coast. This is one of the largest earthquakes that Japan has ever experienced. Tsunami waves swept away houses and cars and caused massive human losses. To predict tsunami wave parameters better and faster, we propose to improve data inversion scheme and achieve the performance gain of data processing. One of the reasons of inaccurate predictions of tsunami parameters is that very little information is available about the initial disturbance of the sea bed at tsunami source. In this paper, we suggest a new way of improving the quality of tsunami source parameters prediction. Modern computational technologies can accurately calculate tsunami wave propagation over the deep ocean provided that the initial displacement (perturbation of the sea bed at tsunami source) is known [4]. Direct geophysical measurements provide the location of an earthquake hypocenter and its magnitude (the released energy evaluation). Among the methods of determination of initial displacement the following ones should be considered. Calculation through the known fault structure and available seismic information. This method is widely used and provides useful information. However, even if the exact knowledge about rock blocks shifts is given, recalculation in terms of sea bed displacement is needed. This results in a certain number of errors. GPS data analysis. This method was developed after the December 2004 event in the Indian Ocean. A good correlation between dry land based GPS sensors and tsunami wave parameters was observed in the particular case of the West coast of Sumatra, Indonesia. This approach is very unique and can hardly been used in other geo locations. Satellite image analysis. The resolution of modern satellite images has dramatically improved. In the future, correct data of sea surface displacement will probably be available in real time, right after a tsunamigenic earthquake. However, today it is not yet possible. Ground-based sea radars. This is an effective tool for direct measurement of tsunami wave. At the same time, the wave is measured at a rather narrow area in front of the radar and does not include information about neighboring parts of the wave. Direct measurement of tsunami wave at deep water [2]. Today, this technology is certainly among the most useful and promising. The DART II® system consists of a seafloor bottom pressure recording (BPR) system, capable of detecting tsunamis as small as 1 cm, and a moored surface buoy for real-time communications. We focus our research on improving the later method, direct measurement of tsunami wave at deep water. We suggest the new way to analyze DART data, modifying the methodology originally proposed by V. Titov. Smaller system of unit sources [3] should be considered to approximate all typical shapes of initial disturbance by several suitable basis functions. To successfully implement it, performance of data analysis should be dramatically improved. This could be done by using a signal orthogonalization procedure for considered system of unit sources and calculation of Fourier coefficients of the measured time series with respect to orthogonal basis. The approach suggested was used as a part of computerized workstation for tsunami hazard monitoring [5-6]. National Oceanic and Atmospheric Administration Center for Tsunami Research. URL: http://nctr.pmel.noaa.gov/honshu20110311/ National Data Buoy Center. URL: http://www.ndbc.noaa.gov/dart.shtml National Oceanic and Atmospheric Administration Center for Tsunami Research. URL: http://sift.pmel.noaa.gov/thredds/dodsC/uncompressed/ National Oceanic and Atmospheric Administration Center for Tsunami Research. URL: http://nctr.pmel.noaa.gov/model.html Alexey Romanenko, Mikhail Lavrentiev-jr, Vasily Titov, "Modern Architecture for Tsunami Hazard Mitigation" // Asia Oceania Geosciences Society (AOGS-2012), ISBN 978-981-07-2049-0 Mikhail Lavrentiev-jr, Andrey Marchuk, Alexey Romanenko, Konstantin Simonov, and Vasiliy Titov, "Computerized Workstation for Tsunami Hazard Monitoring", Geophysical research abstracts, Vol. 12, EGU2010-3021-1, 2010

USEPA Guidance for Designing a Source Water Monitoring System

EPA Science Inventory

Treatment plants are commonly designed and operated to handle typical variability in source water quality, treat contaminants known to occur in source water, comply with drinking water standards, and meet customer expectations. However, unanticipated changes in source water qual...

Formation of N-nitrosodimethylamine (NDMA) from humic substances in natural water.

PubMed

Chen, Zhuo; Valentine, Richard L

2007-09-01

N-nitrosodimethylamine (NDMA)formation in chloraminated Iowa River water (IRW) is primarily attributed to reactions with natural organic matter (NOM) generally classified as humic substances. Experiments were conducted to determine the contribution of various NOM humic fractions to the NDMA formation potential (NDMA FP) in this drinking water source. NOM was concentrated by reverse osmosis (RO) and humic fractions were obtained by a series of resin elution procedures. Mass balances showed that nearly 90% of the NDMA formation potential could be recovered in the NOM concentrate and in water reconstituted using additions of the various humic fractions. Generally, the hydrophilic fractions tended to form more NDMA than hydrophobic fractions, and basic fractions tend to form more NDMA than acid fractions when normalized to a carbon basis. Overall, the hydrophobic acid fraction was the dominant source of NDMA when both formation efficiency and water composition were considered. The amount of NDMA formed in a sample was found to correlate linearly with an oxidation-induced decrease in specific UV absorbance (SUVA) value at 272 nm. This is consistent with a mechanism in which precursors are formed as the direct consequence of the oxidation of NOM. The NDMA FP estimated using the slope of this relationship and the initial SUVA value compared closely to the value obtained by measuring the NDMA formed in solutions dosed with excess concentrations of monochloramine that presumably exhaust all potential precursor sources. However, the NOMA FP could not be correlated to the SUVA value of the individual humic fractions indicating that the relationship of the NDMA FP to SUVA value is probably a water-specific parameter dependent on the exact composition of humic fractions. It is hypothesized that either specific NDMA precursors are distributed among the various humic fractions or that the humic material itself represents a "generic" nonspecific precursor source that requires some degree of oxidation to eventually produce NDMA. The nonmonotonic behavior of NOM fluorescence spectra during chloramination and lack of correlation between NOM fluorescence characteristics and NDMA formation limited the usage of fluorescence spectra into probing NDMA formation.

Technical evaluation of the susceptibility of safety-related systems to flooding caused by the failure of non-Category I systems for Turkey Point Nuclear Power Plant, Units 3 and 4

DOE Office of Scientific and Technical Information (OSTI.GOV)

Collins, E.K.

1979-08-01

Three separate reviews of the Turkey Point Units 3 and 4 were conducted by the FPLCO between 1972 and 1975. Initially, at the request of NBC in 1972, the FPLCO reviewed several water systems as sources of flooding. Subsequently, as a result of an abnormal occurrence, the drainage system was reviewed. Finally, the facilities were again reviewed at NRC's request and both the potential sources of flooding and safety-related equipment which could be damaged by flooding were identified. The sources of flooding and the appropriate safety equipment are discussed. An evaluation is presented of measures that were taken by FPLCOmore » to minimize the danger of flooding and to protect safety-related equipment.« less

Differences in dissolved organic matter between reclaimed water source and drinking water source.

PubMed

Hu, Hong-Ying; Du, Ye; Wu, Qian-Yuan; Zhao, Xin; Tang, Xin; Chen, Zhuo

2016-05-01

Dissolved organic matter (DOM) significantly affects the quality of reclaimed water and drinking water. Reclaimed water potable reuse is an effective way to augment drinking water source and de facto reuse exists worldwide. Hence, when reclaimed water source (namely secondary effluent) is blended with drinking water source, understanding the difference in DOM between drinking water source (dDOM) and reclaimed water source (rDOM) is essential. In this study, composition, transformation, and potential risk of dDOM from drinking water source and rDOM from secondary effluent were compared. Generally, the DOC concentration of rDOM and dissolved organic nitrogen (DON) content in reclaimed water source were higher but rDOM exhibited a lower aromaticity. Besides, rDOM comprises a higher proportion of hydrophilic fractions and more low-molecular weight compounds, which are difficult to be removed during coagulation. Although dDOM exhibited higher specific disinfection byproducts formation potential (SDBPFP), rDOM formed more total disinfection byproducts (DBPs) during chlorination including halomethanes (THMs) and haloacetic acids (HAAs) due to high DOC concentration. Likewise, in consideration of DOC basis, rDOM contained more absolute assimilable organic carbon (AOC) despite showing a lower specific AOC (normalized AOC per unit of DOC). Besides, rDOM exhibited higher biotoxicity including genotoxicity and endocrine disruption. Therefore, rDOM presents a greater potential risk than dDOM does. Reclaimed water source needs to be treated carefully when it is blended with drinking water source. Copyright © 2015. Published by Elsevier B.V.

Effects of human management on black carbon sorption/desorption during a water transfer project: Recognizing impacts and identifying mitigation possibilities.

PubMed

Hao, Rong; Zhang, Jinliang; Wang, Peichao; Hu, Ronggui; Song, Yantun; Wu, Yupeng; Qiu, Guohong

2018-05-15

Water resources management is an important public concern. In this study, we examined the extent of sorption/desorption of trace pollutants to soil black carbon (BC) in the water level fluctuation zone (WLFZ) of the middle route of the South to North Water Transfer Project in China. In addition, we investigated the main management measures affecting these processes during the project. The results showed that the pseudo second-order model adequately describes the sorption/desorption of phenanthrene on the soil BC in the WLFZ. Water level fluctuation may indirectly influenced BC sorption/desorption by altering water chemistry. Water level residence time had negative effects on BC sorption in short-term experiments (days to months), but the impact gradually diminished with increased residence time. The results suggested that long-term field monitoring of water chemistry is urgent. During the initial period of water transfer, delaying the water supplies as drinking water source or directly irrigating crops could mitigate the adverse impacts. Future research should focus on the water-soluble products of BC degradation. The findings of this study should be useful in improving sustainable management of water resources for water transfer projects. Copyright © 2018 Elsevier Ltd. All rights reserved.

Geoacoustic inversion with two source-receiver arrays in shallow water.

PubMed

Sukhovich, Alexey; Roux, Philippe; Wathelet, Marc

2010-08-01

A geoacoustic inversion scheme based on a double beamforming algorithm in shallow water is proposed and tested. Double beamforming allows identification of multi-reverberated eigenrays propagating between two vertical transducer arrays according to their emission and reception angles and arrival times. Analysis of eigenray intensities yields the bottom reflection coefficient as a function of angle of incidence. By fitting the experimental reflection coefficient with a theoretical prediction, values of the acoustic parameters of the waveguide bottom can be extracted. The procedure was initially tested in a small-scale tank experiment for a waveguide with a Plexiglas bottom. Inversion results for the speed of shear waves in Plexiglas are in good agreement with the table values. A similar analysis was applied to data collected during an at-sea experiment in shallow coastal waters of the Mediterranean. Bottom reflection coefficient was fitted with the theory in which bottom sediments are modeled as a multi-layered system. Retrieved bottom parameters are in quantitative agreement with those determined from a prior inversion scheme performed in the same area. The present study confirms the interest in processing source-receiver array data through the double beamforming algorithm, and indicates the potential for application of eigenray intensity analysis to geoacoustic inversion problems.

Label-Free Electrical Immunosensor for Highly Sensitive and Specific Detection of Microcystin-LR in Water Samples.

PubMed

Tan, Feng; Saucedo, Nuvia Maria; Ramnani, Pankaj; Mulchandani, Ashok

2015-08-04

Microcystin-LR (MCLR) is one of the most commonly detected and toxic cyclic heptapeptide cyanotoxins released by cyanobacterial blooms in surface waters, for which sensitive and specific detection methods are necessary to carry out its recognition and quantification. Here, we present a single-walled carbon nanotube (SWCNTs)-based label-free chemiresistive immunosensor for highly sensitive and specific detection of MCLR in different source waters. MCLR was initially immobilized on SWCNTs modified interdigitated electrode, followed by incubation with monoclonal anti-MCLR antibody. The competitive binding of MCLR in sample solutions induced departure of the antibody from the antibody-antigen complexes formed on SWCNTs, resulting in change in the conductivity between source and drain of the sensor. The displacement assay greatly improved the sensitivity of the sensor compared with direct immunoassay on the same device. The immunosensor exhibited a wide linear response to log value of MCLR concentration ranging from 1 to 1000 ng/L, with a detection limit of 0.6 ng/L. This method showed good reproducibility, stability and recovery. The proposed method provides a powerful tool for rapid and sensitive monitoring of MCLR in environmental samples.

Hydrogeologic and geospatial data for the assesment of focused recharge to the Carbonate-Rock Aquifer in Genesee County, New York

USGS Publications Warehouse

Reddy, James E.; Kappel, William M.

2010-01-01

Existing hydrogeologic and geospatial data useful for the assessment of focused recharge to the carbonate-rock aquifer in the central part of Genesee County, NY, were compiled from numerous local, State, and Federal agency sources. Data sources utilized in this pilot study include available geospatial datasets from Federal and State agencies, interviews with local highway departments and the Genesee County Soil and Water Conservation District, and an initial assessment of karst features through the analysis of ortho-photographs, with minimal field verification. The compiled information is presented in a series of county-wide and quadrangle maps. The county-wide maps present generalized hydrogeologic conditions including distribution of geologic units, major faults, and karst features, and bedrock-surface and water-table configurations. Ten sets of quadrangle maps of the area that overlies the carbonate-rock aquifer present more detailed and additional information including distribution of bedrock outcrops, thin and (or) permeable soils, and karst features such as sinkholes and swallets. Water-resource managers can utilize the information summarized in this report as a guide to their assessment of focused recharge to, and the potential for surface contaminants to reach the carbonate-rock aquifer.

Greywater as a sustainable water source: A photocatalytic treatment technology under artificial and solar illumination.

PubMed

Tsoumachidou, Sophia; Velegraki, Theodora; Antoniadis, Apostolos; Poulios, Ioannis

2017-06-15

Greywater considers being a highly reclaimable water source particularly important for water-stressed nations. In this work, heterogeneous photocatalysis using artificial and solar illumination has been applied for the mineralization of simulated light greywater (effluents from dishwashers and kitchen sinks were excluded from the study). The effects on the process' efficiency of TiO 2 P25 catalyst's concentration, initial concentration of H 2 O 2 and Fe 3+ , pH of the solution, as well as the type of radiation, were evaluated in a bench-scale Pyrex reactor and a pilot-scale slurry fountain photoreactor. The treatment efficiency has been followed through the evolution of the organic matter content expresses as dissolved organic carbon (DOC). Best results were obtained with the photo-Fenton-assisted TiO 2 photocatalytic process with 72% DOC removal after 210 min of bench scale treatment, while under the same photocatalytic conditions in the pilot reactor the DOC removal reached almost 64%. Moreover, the decrease in toxicity, phytotoxicity and biodegradability of the simulated wastewater has been observed after solar-induced photocatalytic treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Using continuous in-situ measurements to adaptively trigger urban storm water samples

NASA Astrophysics Data System (ADS)

Wong, B. P.; Kerkez, B.

2015-12-01

Until cost-effective in-situ sensors are available for biological parameters, nutrients and metals, automated samplers will continue to be the primary source of reliable water quality measurements. Given limited samples bottles, however, autosamplers often obscure insights on nutrient sources and biogeochemical processes which would otherwise be captured using a continuous sampling approach. To that end, we evaluate the efficacy a novel method to measure first-flush nutrient dynamics in flashy, urban watersheds. Our approach reduces the number of samples required to capture water quality dynamics by leveraging an internet-connected sensor node, which is equipped with a suite of continuous in-situ sensors and an automated sampler. To capture both the initial baseflow as well as storm concentrations, a cloud-hosted adaptive algorithm analyzes the high-resolution sensor data along with local weather forecasts to optimize a sampling schedule. The method was tested in a highly developed urban catchment in Ann Arbor, Michigan and collected samples of nitrate, phosphorus, and suspended solids throughout several storm events. Results indicate that the watershed does not exhibit first flush dynamics, a behavior that would have been obscured when using a non-adaptive sampling approach.

Isotopic analysis for degradation diagnosis of calcite matrix in mortar.

PubMed

Dotsika, E; Psomiadis, D; Poutoukis, D; Raco, B; Gamaletsos, P

2009-12-01

Mortar that was used in building as well as in conservation and restoration works of wall paintings have been analysed isotopically (delta(13)C and delta(18)O) in order to evaluate the setting environments and secondary processes, to distinguish the structural components used and to determine the exact causes that incurred the degradation phenomena. The material undergoes weathering and decay on a large proportion of its surface and in depth, due to the infiltration of water through the structural blocks. Mineralogical analysis indicated signs of sulphation and dissolution/recrystallisation processes taking place on the material, whereas stable isotopes provided information relative to the origin of the CO(2) and water during calcite formation and degradation processes. Isotopic change of the initial delta(13)C and delta(18)O in carbonate matrix was caused by alteration of the primary source of CO(2) and H(2)O in mortar over time, particularly by recrystallisation of calcite with porewater, evaporated or re-condensed water, and CO(2) from various sources of atmospheric and biogenic origin. Human influence (surface treatment) and biological growth (e.g. fungus) are major exogenic processes which may alter delta(18)O and delta(13)C in lime mortar.

Post-fire Water Quality Response and Associated Physical Drivers

NASA Astrophysics Data System (ADS)

Rust, A.; Saxe, S.; Hogue, T. S.; McCray, J. E.; Rhoades, C.

2017-12-01

The frequency and severity of forest fires is increasing across the western US. Wildfires are known to impact water quality in receiving waters; many of which are important sources of water supply. Studies on individual forest fires have shown an increase in total suspended solids, nutrient and metal concentrations and loading in receiving streams. The current research looks at a large number of fires across a broad region (Western United States) to identify typical water quality changes after fire and the physical characteristics that drive those responses. This presentation will overview recent development of an extensive database on post-fire water quality. Across 172 fires, we found that water quality changed significantly in one out of three fires up to five years after the event compared to pre-burn conditions. For basins with higher frequency data, it was evident that water quality changes were significant in the first three years following fire. In both the initial years following fire and five years after fire, concentrations and loading rates of dissolved nutrients such as nitrite, nitrate and orthophosphate and particulate forms of nutrients, total organic nitrogen, total nitrogen, total phosphate, and total phosphorus increase thirty percent of the time. Concentrations of some major dissolved ions and metals decrease, with increased post-fire flows, while total particulate concentrations increased; the flux of both dissolved and particulate forms increase in thirty percent of the fires over five years. Water quality change is not uniform across the studied watersheds. A second goal of this study is to identify physical characteristics of a watershed that drive water quality response. Specifically, we investigate the physical, geochemical, and climatological characteristics of watersheds that control the type, direction, and magnitude of water quality change. Initial results reveal vegetation recovery is a key driver in post-fire water quality response. Ultimately, improved understanding of post-fire response and related drivers will advance potential mitigation and treatment strategies as well as aid in the parametrization of post-fire models of water quality.

Association of Supply Type with Fecal Contamination of Source Water and Household Stored Drinking Water in Developing Countries: A Bivariate Meta-analysis.

PubMed

Shields, Katherine F; Bain, Robert E S; Cronk, Ryan; Wright, Jim A; Bartram, Jamie

2015-12-01

Access to safe drinking water is essential for health. Monitoring access to drinking water focuses on water supply type at the source, but there is limited evidence on whether quality differences at the source persist in water stored in the household. We assessed the extent of fecal contamination at the source and in household stored water (HSW) and explored the relationship between contamination at each sampling point and water supply type. We performed a bivariate random-effects meta-analysis of 45 studies, identified through a systematic review, that reported either the proportion of samples free of fecal indicator bacteria and/or individual sample bacteria counts for source and HSW, disaggregated by supply type. Water quality deteriorated substantially between source and stored water. The mean percentage of contaminated samples (noncompliance) at the source was 46% (95% CI: 33, 60%), whereas mean noncompliance in HSW was 75% (95% CI: 64, 84%). Water supply type was significantly associated with noncompliance at the source (p < 0.001) and in HSW (p = 0.03). Source water (OR = 0.2; 95% CI: 0.1, 0.5) and HSW (OR = 0.3; 95% CI: 0.2, 0.8) from piped supplies had significantly lower odds of contamination compared with non-piped water, potentially due to residual chlorine. Piped water is less likely to be contaminated compared with other water supply types at both the source and in HSW. A focus on upgrading water services to piped supplies may help improve safety, including for those drinking stored water.

Use of radium isotopes to determine the age and origin of radioactive barite at oil-field production sites

USGS Publications Warehouse

Zielinski, R.A.; Otton, J.K.; Budahn, J.R.

2001-01-01

Radium-bearing barite (radiobarite) is a common constituent of scale and sludge deposits that form in oil-field production equipment. The barite forms as a precipitate from radium-bearing, saline formation water that is pumped to the surface along with oil. Radioactivity levels in some oil-field equipment and in soils contaminated by scale and sludge can be sufficiently high to pose a potential health threat. Accurate determinations of radium isotopes (226Ra+228Ra) in soils are required to establish the level of soil contamination and the volume of soil that may exceed regulatory limits for total radium content. In this study the radium isotopic data are used to provide estimates of the age of formation of the radiobarite contaminant. Age estimates require that highly insoluble radiobarite approximates a chemically closed system from the time of its formation. Age estimates are based on the decay of short-lived 228Ra (half-life=5.76 years) compared to 226Ra (half-life=1600 years). Present activity ratios of 228Ra/226Ra in radiobarite-rich scale or highly contaminated soil are compared to initial ratios at the time of radiobarite precipitation. Initial ratios are estimated by measurements of saline water or recent barite precipitates at the site or by considering a range of probable initial ratios based on reported values in modern oil-field brines. At sites that contain two distinct radiobarite sources of different age, the soils containing mixtures of sources can be identified, and mixing proportions quantified using radium concentration and isotopic data. These uses of radium isotope data provide more description of contamination history and can possibly address liability issues. Copyright ?? 2000 .

Design Drivers of Water Data Services

NASA Astrophysics Data System (ADS)

Valentine, D.; Zaslavsky, I.

2008-12-01

The CUAHSI Hydrologic Information System (HIS) is being developed as a geographically distributed network of hydrologic data sources and functions that are integrated using web services so that they function as a connected whole. The core of the HIS service-oriented architecture is a collection of water web services, which provide uniform access to multiple repositories of observation data. These services use SOAP protocols communicating WaterML (Water Markup Language). When a client makes a data or metadata request using a CUAHSI HIS web service, these requests are made in standard manner, following the CUAHSI HIS web service signatures - regardless of how the underlying data source may be organized. Also, regardless of the format in which the data are returned by the source, the web services respond to requests by returning the data in a standard format of WaterML. The goal of WaterML design has been to capture semantics of hydrologic observations discovery and retrieval and express the point observations information model as an XML schema. To a large extent, it follows the representation of the information model as adopted by the CUASHI Observations Data Model (ODM) relational design. Another driver of WaterML design is specifications and metadata adopted by USGS NWIS, EPA STORET, and other federal agencies, as it seeks to provide a common foundation for exchanging both agency data and data collected in multiple academic projects. Another WaterML design principle was to create, in version 1 of HIS in particular, a fairly rigid and simple XML schema which is easy to generate and parse, thus creating the least barrier for adoption by hydrologists. WaterML includes a series of elements that reflect common notions used in describing hydrologic observations, such as site, variable, source, observation series, seriesCatalog, and data values. Each of the three main request methods in the water web services - GetSiteInfo, GetVariableInfo, and GetValues - has a corresponding response element in WaterML: SitesResponse, VariableResponse, and TimeSeriesResponse. The WaterML specification is being adopted by federal agencies. The experimental USGS NWIS Daily Values web service returns WaterML-compliant TImeSeriesResponse. The National Climatic Data Center is also prototyping WaterML for data delivery, and has developed a REST-based service that generates WaterML- compliant output for the NCDC ASOS network. Such agency-supported web services coming online provide a much more efficient way to deliver agency data compared to the web site scraper services that the CUAHSI HIS project has developed initially. The CUAHSI water data web services will continue to serve as the main communication mechanism within CUAHSI HIS, connecting a variety of data sources with a growing set of web service clients being developed in both academia and the commercial sector. The driving forces for the development of web services continue to be: - Application experience and needs of the growing number of CUAHSI HIS users, who experiment with additional data types, analysis modes, data browsing and searching strategies, and provide feedback to WaterML developers; - Data description requirements posed by various federal and state agencies; - Harmonization with standards being adopted or developed in neighboring communities, in particular the relevant standards being explored within the Open Geospatial Consortium. CUAHSI WaterML is a standard output schema for CUAHSI HIS water web services. Its formal specification is available as OGC discussion paper at www.opengeospatial.org/standards/dp/ class="ab'>

The effect of heat transfer mode on heart rate responses and hysteresis during heating and cooling in the estuarine crocodile Crocodylus porosus.

PubMed

Franklin, Craig E; Seebacher, Frank

2003-04-01

The effect of heating and cooling on heart rate in the estuarine crocodile Crocodylus porosus was studied in response to different heat transfer mechanisms and heat loads. Three heating treatments were investigated. C. porosus were: (1) exposed to a radiant heat source under dry conditions; (2) heated via radiant energy while half-submerged in flowing water at 23 degrees C and (3) heated via convective transfer by increasing water temperature from 23 degrees C to 35 degrees C. Cooling was achieved in all treatments by removing the heat source and with C. porosus half-submerged in flowing water at 23 degrees C. In all treatments, the heart rate of C. porosus increased markedly in response to heating and decreased rapidly with the removal of the heat source. Heart rate during heating was significantly faster than during cooling at any given body temperature, i.e. there was a significant heart rate hysteresis. There were two identifiable responses to heating and cooling. During the initial stages of applying or removing the heat source, there was a dramatic increase or decrease in heart rate ('rapid response'), respectively, indicating a possible cardiac reflex. This rapid change in heart rate with only a small change or no change in body temperature (<0.5 degrees C) resulted in Q(10) values greater than 4000, calling into question the usefulness of this measure on heart rate during the initial stages of heating and cooling. In the later phases of heating and cooling, heart rate changed with body temperature, with Q(10) values of 2-3. The magnitude of the heart rate response differed between treatments, with radiant heating during submergence eliciting the smallest response. The heart rate of C. porosus outside of the 'rapid response' periods was found to be a function of the heat load experienced at the animal surface, as well as on the mode of heat transfer. Heart rate increased or decreased rapidly when C. porosus experienced large positive (above 25 W) or negative (below -15 W) heat loads, respectively, in all treatments. For heat loads between -15 W and 20 W, the increase in heart rate was smaller for the 'unnatural' heating by convection in water compared with either treatment using radiant heating. Our data indicate that changes in heart rate constitute a thermoregulatory mechanism that is modulated in response to the thermal environment occupied by the animal, but that heart rate during heating and cooling is, in part, controlled independently of body temperature.

[Case study of red water phenomenon in drinking water distribution systems caused by water source switch].

PubMed

Wang, Yang; Zhang, Xiao-jian; Chen, Chao; Pan, An-jun; Xu, Yang; Liao, Ping-an; Zhang, Su-xia; Gu, Jun-nong

2009-12-01

Red water phenomenon occurred in some communities of a city in China after water source switch in recent days. The origin of this red water problem and mechanism of iron release were investigated in the study. Water quality of local and new water sources was tested and tap water quality in suffered area had been monitored for 3 months since red water occurred. Interior corrosion scales on the pipe which was obtained from the suffered area were analyzed by XRD, SEM, and EDS. Corrosion rates of cast iron under the conditions of two source water were obtained by Annular Reactor. The influence of different source water on iron release was studied by pipe section reactor to simulate the distribution systems. The results indicated that large increase of sulfate concentration by water source shift was regarded as the cause of red water problem. The Larson ratio increased from about 0.4 to 1.7-1.9 and the red water problem happened in the taps of some urban communities just several days after the new water source was applied. The mechanism of iron release was concluded that the stable shell of scales in the pipes had been corrupted by this kind of high-sulfate-concentration source water and it was hard to recover soon spontaneously. The effect of sulfate on iron release of the old cast iron was more significant than its effect on enhancing iron corrosion. The rate of iron release increased with increasing Larson ratio, and the correlation of them was nonlinear on the old cast-iron. The problem remained quite a long time even if the water source re-shifted into the blended one with only small ratio of the new source and the Larson ratio reduced to about 0.6.

The hydrothermal evolution of the Kawerau geothermal system, New Zealand

NASA Astrophysics Data System (ADS)

Milicich, S. D.; Chambefort, I.; Wilson, C. J. N.; Charlier, B. L. A.; Tepley, F. J.

2018-03-01

Hydrothermal alteration zoning and processes provide insights into the evolution of heat source(s) and fluid compositions associated with geothermal systems. Traditional petrological techniques, combined with hydrothermal alteration studies, stable isotope analyses and geochronology can resolve the nature of the fluids involved in hydrothermal processes and their changes through time. We report here new findings along with previous unpublished works on alteration patterns, fluid inclusion measurements and stable isotope data to provide insights into the thermal and chemical evolution of the Kawerau geothermal system, New Zealand. These data indicate the presence of two hydrothermal events that can be coupled with chronological data. The earlier period of hydrothermal activity was initiated at 400 ka, with the heat driving the hydrothermal system inferred to be from the magmatic system that gave rise to rhyolite lavas and sills of the Caxton Formation. Isotopic data fingerprint fluids attributed to this event as meteoric, indicating that the magma primarily served as a heat source driving fluid circulation, and was not releasing magmatic fluids in sufficient quantity to affect the rock mineralogy and thus inferred fluid compositions. The modern Kawerau system was initiated at 16 ka with hydrothermal eruptions linked to shallow intrusion of magma at the onset of activity that gave rise to the Putauaki andesite cone. Likely associated with this later event was a pulse of magmatic CO2, resulting in large-scale deposition of hydrothermal calcite enriched in 18O. Meteoric water-dominated fluids subsequently overwhelmed the magmatic fluids associated with this 18O-rich signature, and both the fluid inclusion microthermometry and stable isotope data reflect a change to the present-day fluid chemistry of low salinity, meteoric-dominated waters.

Cloud and Radiation Studies during SAFARI 2000

NASA Technical Reports Server (NTRS)

Platnick, Steven; King, M. D.; Hobbs, P. V.; Osborne, S.; Piketh, S.; Bruintjes, R.; Lau, William K. M. (Technical Monitor)

2001-01-01

Though the emphasis of the Southern Africa Regional Science Initiative 2000 (SAFARI-2000) dry season campaign was largely on emission sources and transport, the assemblage of aircraft (including the high altitude NASA ER-2 remote sensing platform and the University of Washington CV-580, UK MRF C130, and South African Weather Bureau JRA in situ aircrafts) provided a unique opportunity for cloud studies. Therefore, as part of the SAFARI initiative, investigations were undertaken to assess regional aerosol-cloud interactions and cloud remote sensing algorithms. In particular, the latter part of the experiment concentrated on marine boundary layer stratocumulus clouds off the southwest coast of Africa. Associated with cold water upwelling along the Benguela current, the Namibian stratocumulus regime has received limited attention but appears to be unique for several reasons. During the dry season, outflow of continental fires and industrial pollution over this area can be extreme. From below, upwelling provides a rich nutrient source for phytoplankton (a source of atmospheric sulphur through DMS production as well as from decay processes). The impact of these natural and anthropogenic sources on the microphysical and optical properties of the stratocumulus is unknown. Continental and Indian Ocean cloud systems of opportunity were also studied during the campaign. Aircraft flights were coordinated with NASA Terra Satellite overpasses for synergy with the Moderate Resolution Imaging Spectroradiometer (MODIS) and other Terra instruments. An operational MODIS algorithm for the retrieval of cloud optical and physical properties (including optical thickness, effective particle radius, and water path) has been developed. Pixel-level MODIS retrievals (11 km spatial resolution at nadir) and gridded statistics of clouds in th SAFARI region will be presented. In addition, the MODIS Airborne Simulator flown on the ER-2 provided high spatial resolution retrievals (50 m at nadir). These retrievals will be discussed and compared with in situ observations.

Quantifying nitrogen inputs to the Choptank River estuary

NASA Astrophysics Data System (ADS)

Mccarty, G.; Hapeman, C. J.; Sadeghi, A. M.; Hively, W. D.; Denver, J. M.; Lang, M. W.; Downey, P. M.; Rice, C. P.

2015-12-01

The Chesapeake Bay is the largest estuary in the US, and over 50% of its streams have been rated as poor or very poor, based on the biological integrity yearly index. The Choptank River, a Bay tributary on the Delmarva Peninsula, is dominated by intensive corn and soybean farming associated with poultry and some dairy production. The Choptank River is under Environmental Protection Agency (USEPA) total maximum daily load restrictions. However, reducing nonpoint source pollution contributions from agriculture requires that source predictions be improved and that mitigation and conservation measures be properly targeted. Therefore, new measurement strategies have been implemented. In-situ sensors have been deployed adjacent to US Geological Survey gauging stations in the Tuckahoe and Greensboro sub-basins of the Choptank River watershed. These sensors measure stream water concentrations of nitrate along and water quality parameters every 30 min. Initial results indicate that ~40% less nitrate is exported from the Greensboro sub-basin, even though the total amount of agricultural land use is similar to that in the Tuckahoe sub-basin. This is most likely due to more efficient nitrate processing in the Greensboro sub-basin where the amount of cropland on poorly-drained soils is much larger. Another potential nitrogen source to the Choptank River estuary is atmospheric deposition of ammonia. Over 550 million broilers are produced yearly on the Delmarva Peninsula potentially leading to the release of 20,000 Mtons of ammonia. USEPA recently estimated that as much as 22% of nitrogen in the Bay is due to ammonia deposition. We have initiated a collaborative effort within the LTAR network to increase coverage of ammonia sampling and to explore the spatial and temporal variability of ammonia, particularly in the Choptank River watershed. All these measurements will be useful in improving the handling of nitrogen sources and its fate and transport in the Chesapeake Bay model.

Association of Supply Type with Fecal Contamination of Source Water and Household Stored Drinking Water in Developing Countries: A Bivariate Meta-analysis

PubMed Central

Bain, Robert E.S.; Cronk, Ryan; Wright, Jim A.; Bartram, Jamie

2015-01-01

Background Access to safe drinking water is essential for health. Monitoring access to drinking water focuses on water supply type at the source, but there is limited evidence on whether quality differences at the source persist in water stored in the household. Objectives We assessed the extent of fecal contamination at the source and in household stored water (HSW) and explored the relationship between contamination at each sampling point and water supply type. Methods We performed a bivariate random-effects meta-analysis of 45 studies, identified through a systematic review, that reported either the proportion of samples free of fecal indicator bacteria and/or individual sample bacteria counts for source and HSW, disaggregated by supply type. Results Water quality deteriorated substantially between source and stored water. The mean percentage of contaminated samples (noncompliance) at the source was 46% (95% CI: 33, 60%), whereas mean noncompliance in HSW was 75% (95% CI: 64, 84%). Water supply type was significantly associated with noncompliance at the source (p < 0.001) and in HSW (p = 0.03). Source water (OR = 0.2; 95% CI: 0.1, 0.5) and HSW (OR = 0.3; 95% CI: 0.2, 0.8) from piped supplies had significantly lower odds of contamination compared with non-piped water, potentially due to residual chlorine. Conclusions Piped water is less likely to be contaminated compared with other water supply types at both the source and in HSW. A focus on upgrading water services to piped supplies may help improve safety, including for those drinking stored water. Citation Shields KF, Bain RE, Cronk R, Wright JA, Bartram J. 2015. Association of supply type with fecal contamination of source water and household stored drinking water in developing countries: a bivariate meta-analysis. Environ Health Perspect 123:1222–1231; http://dx.doi.org/10.1289/ehp.1409002 PMID:25956006

Permitted water use in Iowa, 1985

USGS Publications Warehouse

Runkle, D.L.; Newman, J.L.; Shields, E.M.

1985-01-01

This report summarizes where, how much and for what purpose water is allocated for use in Iowa with permits issued by the Department of Water, Air and Waste Management. In Iowa, from a total permitted water use of 855,175.45 million gallons per year, about 58 percent is from surface-water sources and about 42 percent is from ground-water sources. Streams are 80.5 percent of the total surface-water use and wells make up 80.1 percent of the total ground-water use, with 65.4 percent of ground water coming from surficial aquifers. Power generation is the use category that is permitted the largest amount of total water use, 46.6 percent, with surface water being the source of 96.7 percent and 77.9 percent of the surface water is from streams. The public water suppliers' category is the next largest use type with 15.7 percent of the total permitted water. Ground water constitutes 74.4 percent of the public water supplier category with 51.7 percent from surficial aquifers. Surface water makes up 25.6 percent of this category with 83.0 percent of the surface water withdrawn from streams. Mining comprises 13.4 percent of the total water use and is the third largest water-use category. Ground water is the source of 63.3 percent of permitted mining water use with 94.3 percent of this from quarries and sand and gravel pits. Surface water is the source of 36.7 percent of the permitted mining water use with 97.6 percent from streams. Irrigation is the fourth largest permitted use type using 12.0 percent of the total water use. Eighty-eight percent of irrigation is from ground-water sources where surficial aquifers account for 94.7 percent. Streams are 81.1 percent of irrigational surface-water use. Self-supplied industrial users are permitted 10.6 percent of the total permitted water use with 85.5 percent of this from ground-water sources and 14.5 percent from surface-water sources. Of the self-supplied industrial ground-water use, 47.9 percent comes from surficial aquifers and of the self-supplied industrial surface-water use 86.1 percent is from streams. Self-supplied commercial use is allocated 1.5 percent of the total permitted water. Surface-water is the source of 37.7 percent of this and 62.3 percent is from ground-water sources. Agricultural (non-irrigation) use is 0.3 percent of the total permitted water with 73.3 percent from groundwater sources and 26.7 percent from surface-water sources. The areas that are allocated the most water permits are east-central Iowa and west-central Iowa.

How to Manual: How to Update and Enhance Your Local Source Water Protection Assessments

EPA Pesticide Factsheets

Describes opportunities for improving source water assessments performed under the Safe Drinking Water Act 1453. It includes: local delineations, potential contaminant source inventories, and susceptibility determinations of source water assessment.

Chabazite and dolomite formation in a dolocrete profile: An example of a complex alkaline paragenesis in Lanzarote, Canary Islands

NASA Astrophysics Data System (ADS)

Alonso-Zarza, Ana M.; Bustamante, Leticia; Huerta, Pedro; Rodríguez-Berriguete, Álvaro; Huertas, María José

2016-05-01

This paper studies the weathering and soil formation processes operating on detrital sediments containing alkaline volcanic rock fragments of the Mirador del Río dolocrete profile. The profile consists of a lower horizon of removilised weathered basalts, an intermediate red sandy mudstones horizon with irregular carbonate layers and a topmost horizon of amalgamated carbonate layers with root traces. Formation occurred in arid to semiarid climates, giving place to a complex mineralogical association, including Mg-carbonates and chabazite, rarely described in cal/dolocretes profiles. Initial vadose weathering processes occurred in the basalts and in directly overlying detrital sediments, producing (Stage 1) red-smectites and dolomicrite. Dominant phreatic (Stage 2) conditions allowed precipitation of coarse-zoned dolomite and chabazite filling porosities. In Stages 3 and 4, mostly pedogenic, biogenic processes played an important role in dolomite and calcite accumulation in the profile. Overall evolution of the profile and its mineralogical association involved initial processes dominated by alteration of host rock, to provide silica and Mg-rich alkaline waters, suitable for chabazite and dolomite formation, without a previous carbonate phase. Dolomite formed both abiogenically and biogenically, but without a previous carbonate precursor and in the absence of evaporites. Dominance of calcite towards the profile top is the result of Mg/Ca decrease in the interstitial meteoric waters due to decreased supply of Mg from weathering, and increased supply of Ca in aeolian dust. Meteoric origin of the water is confirmed by C and O isotope values, which also indicate lack of deep sourced CO2. The dolocrete studied and its complex mineral association reveal the complex interactions that occur at surface during weathering and pedogenesis of basalt-sourced rocks.

A comparison of large-scale electron beam and bench-scale 60Co irradiations of simulated aqueous waste streams

NASA Astrophysics Data System (ADS)

Kurucz, Charles N.; Waite, Thomas D.; Otaño, Suzana E.; Cooper, William J.; Nickelsen, Michael G.

2002-11-01

The effectiveness of using high energy electron beam irradiation for the removal of toxic organic chemicals from water and wastewater has been demonstrated by commercial-scale experiments conducted at the Electron Beam Research Facility (EBRF) located in Miami, Florida and elsewhere. The EBRF treats various waste and water streams up to 450 l min -1 (120 gal min -1) with doses up to 8 kilogray (kGy). Many experiments have been conducted by injecting toxic organic compounds into various plant feed streams and measuring the concentrations of compound(s) before and after exposure to the electron beam at various doses. Extensive experimentation has also been performed by dissolving selected chemicals in 22,700 l (6000 gal) tank trucks of potable water to simulate contaminated groundwater, and pumping the resulting solutions through the electron beam. These large-scale experiments, although necessary to demonstrate the commercial viability of the process, require a great deal of time and effort. This paper compares the results of large-scale electron beam irradiations to those obtained from bench-scale irradiations using gamma rays generated by a 60Co source. Dose constants from exponential contaminant removal models are found to depend on the source of radiation and initial contaminant concentration. Possible reasons for observed differences such as a dose rate effect are discussed. Models for estimating electron beam dose constants from bench-scale gamma experiments are presented. Data used to compare the removal of organic compounds using gamma irradiation and electron beam irradiation are taken from the literature and a series of experiments designed to examine the effects of pH, the presence of turbidity, and initial concentration on the removal of various organic compounds (benzene, toluene, phenol, PCE, TCE and chloroform) from simulated groundwater.

Modeling the 16 September 2015 Chile tsunami source with the inversion of deep-ocean tsunami records by means of the r - solution method

NASA Astrophysics Data System (ADS)

Voronina, Tatyana; Romanenko, Alexey; Loskutov, Artem

2017-04-01

The key point in the state-of-the-art in the tsunami forecasting is constructing a reliable tsunami source. In this study, we present an application of the original numerical inversion technique to modeling the tsunami sources of the 16 September 2015 Chile tsunami. The problem of recovering a tsunami source from remote measurements of the incoming wave in the deep-water tsunameters is considered as an inverse problem of mathematical physics in the class of ill-posed problems. This approach is based on the least squares and the truncated singular value decomposition techniques. The tsunami wave propagation is considered within the scope of the linear shallow-water theory. As in inverse seismic problem, the numerical solutions obtained by mathematical methods become unstable due to the presence of noise in real data. A method of r-solutions makes it possible to avoid instability in the solution to the ill-posed problem under study. This method seems to be attractive from the computational point of view since the main efforts are required only once for calculating the matrix whose columns consist of computed waveforms for each harmonic as a source (an unknown tsunami source is represented as a part of a spatial harmonics series in the source area). Furthermore, analyzing the singular spectra of the matrix obtained in the course of numerical calculations one can estimate the future inversion by a certain observational system that will allow offering a more effective disposition for the tsunameters with the help of precomputations. In other words, the results obtained allow finding a way to improve the inversion by selecting the most informative set of available recording stations. The case study of the 6 February 2013 Solomon Islands tsunami highlights a critical role of arranging deep-water tsunameters for obtaining the inversion results. Implementation of the proposed methodology to the 16 September 2015 Chile tsunami has successfully produced tsunami source model. The function recovered by the method proposed can find practical applications both as an initial condition for various optimization approaches and for computer calculation of the tsunami wave propagation.

Instrumentation and signal processing for the detection of heavy water using off axis-integrated cavity output spectroscopy technique

NASA Astrophysics Data System (ADS)

Gupta, A.; Singh, P. J.; Gaikwad, D. Y.; Udupa, D. V.; Topkar, A.; Sahoo, N. K.

2018-02-01

An experimental setup is developed for the trace level detection of heavy water (HDO) using the off axis-integrated cavity output spectroscopy technique. The absorption spectrum of water samples is recorded in the spectral range of 7190.7 cm-1-7191.5 cm-1 with the diode laser as the light source. From the recorded water vapor absorption spectrum, the heavy water concentration is determined from the HDO and water line. The effect of cavity gain nonlinearity with per pass absorption is studied. The signal processing and data fitting procedure is devised to obtain linear calibration curves by including nonlinear cavity gain effects into the calculation. Initial calibration of mirror reflectivity is performed by measurements on the natural water sample. The signal processing and data fitting method has been validated by the measurement of the HDO concentration in water samples over a wide range from 20 ppm to 2280 ppm showing a linear calibration curve. The average measurement time is about 30 s. The experimental technique presented in this paper could be applied for the development of a portable instrument for the fast measurement of water isotopic composition in heavy water plants and for the detection of heavy water leak in pressurized heavy water reactors.

Drinking cholera: salinity levels and palatability of drinking water in coastal Bangladesh.

PubMed

Grant, Stephen Lawrence; Tamason, Charlotte Crim; Hoque, Bilqis Amin; Jensen, Peter Kjaer Mackie

2015-04-01

To measure the salinity levels of common water sources in coastal Bangladesh and explore perceptions of water palatability among the local population to investigate the plausibility of linking cholera outbreaks in Bangladesh with ingestion of saline-rich cholera-infected river water. Hundred participants took part in a taste-testing experiment of water with varying levels of salinity. Salinity measurements were taken of both drinking and non-drinking water sources. Informal group discussions were conducted to gain an in-depth understanding of water sources and water uses. Salinity levels of non-drinking water sources suggest that the conditions for Vibrio cholerae survival exist 7-8 days within the local aquatic environment. However, 96% of participants in the taste-testing experiment reported that they would never drink water with salinity levels that would be conducive to V. cholerae survival. Furthermore, salinity levels of participant's drinking water sources were all well below the levels required for optimal survival of V. cholerae. Respondents explained that they preferred less salty and more aesthetically pleasing drinking water. Theoretically, V. cholerae can survive in the river systems in Bangladesh; however, water sources which have been contaminated with river water are avoided as potential drinking water sources. Furthermore, there are no physical connecting points between the river system and drinking water sources among the study population, indicating that the primary driver for cholera cases in Bangladesh is likely not through the contamination of saline-rich river water into drinking water sources. © 2015 John Wiley & Sons Ltd.

An Integrated Hydrological and Water Management Study of the Entire Nile River System - Lake Victoria to Nile Delta

NASA Technical Reports Server (NTRS)

Habib, Shahid; Zaitchik, Benjamin; Alo, Clement; Ozdogan, Mutlu; Anderson, Martha; Policelli, Fritz

2011-01-01

The Nile basin River system spans 3 million km(exp 2) distributed over ten nations. The eight upstream riparian nations, Ethiopia, Eretria, Uganda, Rwanda, Burundi, Congo, Tanzania and Kenya are the source of approximately 86% of the water inputs to the Nile, while the two downstream riparian countries Sudan and Egypt, presently rely on the river's flow for most of the their needs. Both climate and agriculture contribute to the complicated nature of Nile River management: precipitation in the headwaters regions of Ethiopia and Lake Victoria is variable on a seasonal and inter-annual basis, while demand for irrigation water in the arid downstream region is consistently high. The Nile is, perhaps, one of the most difficult trans-boundary water issue in the world, and this study would be the first initiative to combine NASA satellite observations with the hydrologic models study the overall water balance in a to comprehensive manner. The cornerstone application of NASA's Earth Science Research Results under this project are the NASA Land Data Assimilation System (LDAS) and the USDA Atmosphere-land Exchange Inverse (ALEXI) model. These two complementary research results are methodologically independent methods for using NASA observations to support water resource analysis in data poor regions. Where an LDAS uses multiple sources of satellite data to inform prognostic simulations of hydrological process, ALEXI diagnoses evapotranspiration and water stress on the basis of thermal infrared satellite imagery. Specifically, this work integrates NASA Land Data Assimilation systems into the water management decision support systems that member countries of the Nile Basin Initiative (NBI) and Regional Center for Mapping of Resources for Development (RCMRD, located in Nairobi, Kenya) use in water resource analysis, agricultural planning, and acute drought response to support sustainable development of Nile Basin water resources. The project is motivated by the recognition that accurate, frequent, and spatially distributed estimates of the water balance are necessary for effective water management. This creates a challenge for watersheds that are large, include data poor regions, and/or span multiple nations. All of these descriptors apply to the Nile River basin, yet successful management of the Nile is critical for development and political stability in the region. For this reason, improved hydrological data to support cooperative water management in the Nile basin is a priority for USAID, the US State Department, the World Bank and other international organizations. In this project, the U.S. based research team is working with partners at RCMRD, Nile Basin Initiative (NBI), and their member national-level agencies to develop satellite-based land cover maps, satellite-derived evapotranspiration estimates (using the ALEXI algorithm), and NASA's Land Data Assimilation System (LDAS) customized to match identified information needs. The cornerstone applied sciences product of the project is the development of a customized "Nile LDAS" that will produce optimal estimates of hydrological states and fluxes, as vetted against the in situ observations of NBI and RCMRD member organizations and independent satellite-derived hydrological estimates. Nile LDAS will be applied to improve the reliability of emerging Decision Support Systems in applications that include drought monitoring, reservoir management, and irrigation planning. The end-users such as RCMRD, NBI, Ethiopian and Kenya Meteorological and Famine Early Warning System Network (FEWSNet) will be the eventual benefactors of this work. There will be a capacity building process involving the above end-user organizations and transfer the models and the results for these organizations to execute for future use. The team has already initiated this study and the early results of first years' work are shown. The plan is to complete this work by late 2013.

On The Computation Of The Best-fit Okada-type Tsunami Source

NASA Astrophysics Data System (ADS)

Miranda, J. M. A.; Luis, J. M. F.; Baptista, M. A.

2017-12-01

The forward simulation of earthquake-induced tsunamis usually assumes that the initial sea surface elevation mimics the co-seismic deformation of the ocean bottom described by a simple "Okada-type" source (rectangular fault with constant slip in a homogeneous elastic half space). This approach is highly effective, in particular in far-field conditions. With this assumption, and a given set of tsunami waveforms recorded by deep sea pressure sensors and (or) coastal tide stations it is possible to deduce the set of parameters of the Okada-type solution that best fits a set of sea level observations. To do this, we build a "space of possible tsunami sources-solution space". Each solution consists of a combination of parameters: earthquake magnitude, length, width, slip, depth and angles - strike, rake, and dip. To constrain the number of possible solutions we use the earthquake parameters defined by seismology and establish a range of possible values for each parameter. We select the "best Okada source" by comparison of the results of direct tsunami modeling using the solution space of tsunami sources. However, direct tsunami modeling is a time-consuming process for the whole solution space. To overcome this problem, we use a precomputed database of Empirical Green Functions to compute the tsunami waveforms resulting from unit water sources and search which one best matches the observations. In this study, we use as a test case the Solomon Islands tsunami of 6 February 2013 caused by a magnitude 8.0 earthquake. The "best Okada" source is the solution that best matches the tsunami recorded at six DART stations in the area. We discuss the differences between the initial seismic solution and the final one obtained from tsunami data This publication received funding of FCT-project UID/GEO/50019/2013-Instituto Dom Luiz.

Deep-towed high resolution seismic imaging II: Determination of P-wave velocity distribution

NASA Astrophysics Data System (ADS)

Marsset, B.; Ker, S.; Thomas, Y.; Colin, F.

2018-02-01

The acquisition of high resolution seismic data in deep waters requires the development of deep towed seismic sources and receivers able to deal with the high hydrostatic pressure environment. The low frequency piezoelectric transducer of the SYSIF (SYstème Sismique Fond) deep towed seismic device comply with the former requirement taking advantage of the coupling of a mechanical resonance (Janus driver) and a fluid resonance (Helmholtz cavity) to produce a large frequency bandwidth acoustic signal (220-1050 Hz). The ability to perform deep towed multichannel seismic imaging with SYSIF was demonstrated in 2014, yet, the ability to determine P-wave velocity distribution wasn't achieved. P-wave velocity analysis relies on the ratio between the source-receiver offset range and the depth of the seismic reflectors, thus towing the seismic source and receivers closer to the sea bed will provide a better geometry for P-wave velocity determination. Yet, technical issues, related to the acoustic source directivity, arise for this approach in the particular framework of piezoelectric sources. A signal processing sequence is therefore added to the initial processing flow. Data acquisition took place during the GHASS (Gas Hydrates, fluid Activities and Sediment deformations in the western Black Sea) cruise in the Romanian waters of the Black Sea. The results of the imaging processing are presented for two seismic data sets acquired over gas hydrates and gas bearing sediments. The improvement in the final seismic resolution demonstrates the validity of the velocity model.

Long Term 2 Second Round Source Water Monitoring and Bin Placement Memo

EPA Pesticide Factsheets

The Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR) applies to all public water systems served by a surface water source or public water systems served by a ground water source under the direct influence of surface water.

Seasonality of Red Sea Mixed-Layer Depth and Density Budget

NASA Astrophysics Data System (ADS)

Kartadikaria, A. R.; Cerovecki, I.; Krokos, G.; Hoteit, I.

2016-02-01

The Red Sea is an active area of water mass formation. Dense water initially formed in the northern Red Sea, in the Gulf of Aqaba and the Gulf of Suez, spreads southward and finally flows to the open ocean through the Gulf of Aden via the narrow strait of Bab Al Mandeb. The signature of this outflow can be traced until the southern Indian Ocean, and is characterized by potential density of σθ ≈ 27.4. This water mass is important because it represents a significant source of heat and salt for the Indian Ocean. Using a high-resolution 1km regional MITgcm ocean model for the period 1992-2001 configured for the Red Sea, we examine the spatio-temporal characteristics of water mass formation inside the basin by analyzing closed and complete temperature and salinity budgets. The deepest mixed-layers (MLD) always develop in the northern part of the basin where surface ocean buoyancy loss leads to the Red Sea Intermediate and Deep Water formation. As this water is advected south, it is strongly modified by diapycnal mixing of heat and salt.

Scientific approach and practical experience for reconstruction of waste water treatment plants in Russia

NASA Astrophysics Data System (ADS)

Makisha, Nikolay; Gogina, Elena

2017-11-01

Protection of water bodies has a strict dependence on reliable operation of engineering systems and facilities for water supply and sewage. The majority of these plants and stations has been constructed in 1970-1980's in accordance with rules and regulations of that time. So now most of them require reconstruction due to serious physical or/and technological wear. The current condition of water supply and sewage systems and facilities frequently means a hidden source of serious danger for normal life support and ecological safety of cities and towns. The article reveals an obtained experience and modern approaches for reconstruction of waste water and sludge treatment plants that proved their efficiency even if applied in limited conditions such as area limits, investments limits. The main directions of reconstruction: overhaul repair and partial modernization of existing facilities on the basis of initial project; - restoration and modernization of existing systems on the basis on the current documents and their current condition; upgrade of waste water treatment plants (WWTPs) performance on the basis of modern technologies and methods; reconstruction of sewage systems and facilities and treatment quality improvement.

Simulations of groundwater flow and particle-tracking analysis in the zone of contribution to a public-supply well in San Antonio, Texas

USGS Publications Warehouse

Lindgren, Richard L.; Houston, Natalie A.; Musgrove, MaryLynn; Fahlquist, Lynne S.; Kauffman, Leon J.

2011-01-01

The effect of short-circuit pathways, for example karst conduits, in the flow system on the movement of young water to the selected public-supply well could greatly alter contaminant arrival times compared to what might be expected from advection in a system without short circuiting. In a forecasting exercise, the simulated concentrations showed rapid initial response at the beginning and end of chemical input, followed by more gradual response as older water moved through the system. The nature of karst groundwater flow, where flow predominantly occurs via conduit flow paths, could lead to relatively rapid water quality responses to land-use changes. Results from the forecasting exercise indicate that timescales for change in the quality of water from the selected public-supply well could be on the order of a few years to decades for land-use changes that occur over days to decades, which has implications for source-water protection strategies that rely on land-use change to achieve water-quality objectives.

Electrical Resistivity Technique for Groundwater Exploration in Quaternary Deposit

NASA Astrophysics Data System (ADS)

Aziman, M.; Hazreek, Z. A. M.; Azhar, A. T. S.; Fahmy, K. A.; Faizal, T. B. M.; Sabariah, M.; Ambak, K.; Ismail, M. A. M.

2018-04-01

The water security for University Tun Hussein Onn (UTHM) campus was initiated to find alternative sources of water supply. This research began with finding the soil profiles using the geophysical electrical resistivity method across UTHM campus. The resistivity results were calibrated with previous borehole data as well as via groundwater drilling. The drilling work was discovered the groundwater aquifer characterized by the fractured fresh igneous rock at a depth between 43 meter and 55 meter. Further drilling was continued until 100 meter in depth. However, due to not encounter a new rock fractured zone causes the groundwater quantity did not improve even was drilled up to 100 meter depth. In the perspective of water resources, it showed a good potential for water resources for local usages at 104 m3 per day. In addition, the groundwater quality showed the water treatment was required to fulfil the criterion of the national drinking water standards. This study concluded that the first layer of fractured bedrock at UTHM was able to produce significant amounts of groundwater for local consumption usage.

Analysis of Orientation-dependence of Martian Gullies

NASA Technical Reports Server (NTRS)

Mohan, S.; Bridges, N. T.

2004-01-01

The recent discovery of small Martian gullies has stimulated debate about the role that water plays on the Martian surface under current or recent conditions. Of critical importance in evaluating various gully hypotheses is reliable morphometric and orientation data. The former centers on such questions as whether the water (or another fluid) emanated from a surface or sub-surface source and the duration of flow. The latter ties into whether solar insolation has an important effect on formation of the initial water source and subsequent mobilization. Initial studies of gullies indicated a poleward orientation dependence, an observation which has recently been challenged. Herein we investigate the orientation of Martian gullies and the dependence of various parameters on the orientation. Whereas previous studies have been global or through most of the southern hemisphere, we focus on several specific regions. This approach offers some advantages in that regional variations are factored out, such that of lithology, ground water table depth (if any), surface thermal properties, and other parameters are more or less the same in a given region. Differences in gully attributes as a function of orientation within a region can more easily be attributable to solar insolation effects than is the case for global statistics. We use the orientation to constrain several classes of gully formation hypotheses. 1) A favored orientation toward the pole across all regions could indicate a process dominated by melting of cold trapped ice, snow, or condensed volatiles from incident sunlight during summer under current conditions. 2) Variations among all regions would be more consistent with mechanisms less strongly tied to current solar insolation, such as geothermal heating of ice. 3) Favored orientations within specific regions, but differing among regions, could indicate a preference for poleward ices and melting, with orientation being a function of age and dependent on variations in obliquity and precision. We find that the gullies fall into either categories 2 or 3, but not 1, indicating the recent melting of cold trapped condensates is unlikely the sole formation mechanism.

Short-range precipitation forecasts using assimilation of simulated satellite water vapor profiles and column cloud liquid water amounts

NASA Technical Reports Server (NTRS)

Wu, Xiaohua; Diak, George R.; Hayden, Cristopher M.; Young, John A.

1995-01-01

These observing system simulation experiments investigate the assimilation of satellite-observed water vapor and cloud liquid water data in the initialization of a limited-area primitive equations model with the goal of improving short-range precipitation forecasts. The assimilation procedure presented includes two aspects: specification of an initial cloud liquid water vertical distribution and diabatic initialization. The satellite data is simulated for the next generation of polar-orbiting satellite instruments, the Advanced Microwave Sounding Unit (AMSU) and the High-Resolution Infrared Sounder (HIRS), which are scheduled to be launched on the NOAA-K satellite in the mid-1990s. Based on cloud-top height and total column cloud liquid water amounts simulated for satellite data a diagnostic method is used to specify an initial cloud water vertical distribution and to modify the initial moisture distribution in cloudy areas. Using a diabatic initialization procedure, the associated latent heating profiles are directly assimilated into the numerical model. The initial heating is estimated by time averaging the latent heat release from convective and large-scale condensation during the early forecast stage after insertion of satellite-observed temperature, water vapor, and cloud water formation. The assimilation of satellite-observed moisture and cloud water, together withy three-mode diabatic initialization, significantly alleviates the model precipitation spinup problem, especially in the first 3 h of the forecast. Experimental forecasts indicate that the impact of satellite-observed temperature and water vapor profiles and cloud water alone in the initialization procedure shortens the spinup time for precipitation rates by 1-2 h and for regeneration of the areal coverage by 3 h. The diabatic initialization further reduces the precipitation spinup time (compared to adiabatic initialization) by 1 h.

Seasonal Thermal Energy Storage Program

NASA Technical Reports Server (NTRS)

Minor, J. E.

1980-01-01

The Seasonal Thermal Energy Storage (STES) Program designed to demonstrate the storage and retrieval of energy on a seasonal basis using heat or cold available from waste or other sources during a surplus period is described. Factors considered include reduction of peak period demand and electric utility load problems and establishment of favorable economics for district heating and cooling systems for commercialization of the technology. The initial thrust of the STES Program toward utilization of ground water systems (aquifers) for thermal energy storage is emphasized.

Resilience Analysis of Face Slopes and Internal Dumps and Causes of their Instability at “Mugunsky” Opencast Coal Mine

NASA Astrophysics Data System (ADS)

Zagibalov, A. V.; Okhotin, A. L.; Volokhov, A. V.

2017-10-01

The paper deals with the problems of initiation and consequences of landslide processes registered in the internal dumps at Mugunsky lignite opencast mine. Water cutting at the internal dump base, availability of clay rocks in the dump bottom, and the bottom incline towards the working face are revealed to be the sources of the landslide process. Some measures are recommended to prevent deformation processes that are possible to take place in the run of mine development.

Multiple Household Water Sources and Their Use in Remote Communities With Evidence From Pacific Island Countries

NASA Astrophysics Data System (ADS)

Elliott, Mark; MacDonald, Morgan C.; Chan, Terence; Kearton, Annika; Shields, Katherine F.; Bartram, Jamie K.; Hadwen, Wade L.

2017-11-01

Global water research and monitoring typically focus on the household's "main source of drinking-water." Use of multiple water sources to meet daily household needs has been noted in many developing countries but rarely quantified or reported in detail. We gathered self-reported data using a cross-sectional survey of 405 households in eight communities of the Republic of the Marshall Islands (RMI) and five Solomon Islands (SI) communities. Over 90% of households used multiple sources, with differences in sources and uses between wet and dry seasons. Most RMI households had large rainwater tanks and rationed stored rainwater for drinking throughout the dry season, whereas most SI households collected rainwater in small pots, precluding storage across seasons. Use of a source for cooking was strongly positively correlated with use for drinking, whereas use for cooking was negatively correlated or uncorrelated with nonconsumptive uses (e.g., bathing). Dry season water uses implied greater risk of water-borne disease, with fewer (frequently zero) handwashing sources reported and more unimproved sources consumed. Use of multiple sources is fundamental to household water management and feasible to monitor using electronic survey tools. We contend that recognizing multiple water sources can greatly improve understanding of household-level and community-level climate change resilience, that use of multiple sources confounds health impact studies of water interventions, and that incorporating multiple sources into water supply interventions can yield heretofore-unrealized benefits. We propose that failure to consider multiple sources undermines the design and effectiveness of global water monitoring, data interpretation, implementation, policy, and research.

Evaluation of on-line concentration coupled to liquid chromatography tandem mass spectrometry for the quantification of neonicotinoids and fipronil in surface water and tap water.

PubMed

Montiel-León, Juan Manuel; Duy, Sung Vo; Munoz, Gabriel; Amyot, Marc; Sauvé, Sébastien

2018-04-01

A study was initiated to investigate a fast and reliable method for the determination of selected systemic insecticides in water matrixes and to evaluate potential sources of bias in their analysis. Acetamiprid, clothianidin, desnitro-imidacloprid, dinotefuran, fipronil, imidacloprid, nitenpyram, thiacloprid, and thiamethoxam were amenable to analysis via on-line sample enrichment hyphenated to ultra-high-performance liquid chromatography tandem mass spectrometry. The selection of on-line solid-phase extraction parameters was dictated by a multicriterion desirability approach. A 2-mL on-line injection volume with a 1500 μL min -1 loading flow rate met the objectives sought in terms of chromatographic requirements, extraction efficiency, sensitivity, and precision. A total analysis time of 8 min per sample was obtained with method limits of detection in the range of 0.1-5 ng L -1 for the scope of targeted analytes. Automation at the sample concentration step yielded intraday and interday precisions in the range of 1-23 and 2-26%, respectively. Factors that could affect the whole method accuracy were further evaluated in matrix-specific experiments. The impact of the initial filtration step on analyte recovery was evaluated in ultra-pure water, tap water, and surface water. Out of the nine membranes tested, glass fiber filters and polyester filters appeared as the most appropriate materials. Sample storage stability was also investigated across the three matrix types; the targeted analytes displayed suitable stability during 28 days at either 4 °C or - 20 °C, with little deviations (± 10%) with respect to the initial T 0 concentration. Method applicability was demonstrated in a range of tap water and surface water samples from the province of Québec, Canada. Results from the present survey indicated a predominance of thiamethoxam (< 0.5-10 and 3-61 ng L -1 in tap water and river water, respectively), clothianidin (< 0.5-6 and 2-88 ng L -1 in tap water and river water, respectively), and imidacloprid (< 0.1-1 and 0.8-38 ng L -1 in tap water and river water, respectively) among the targeted analytes. Graphical abstract ᅟ Development of solid-phase extraction coupled on-line to UHPLC-MS/MS for the rapid screening of systemic insecticides in water.

Using naturally occurring radionuclides to determine drinking water age in a community water system

DOE PAGES

Waples, James T.; Bordewyk, Jason K.; Knesting, Kristina M.; ...

2015-07-22

Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of 90Y/ 90Sr and 234Th/ 238U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (σ est: ± 3.8 h, P < 0.0001, r 2more » = 0.998, n = 11) and 25 days old (σ est: ± 13.3 h, P < 0.0001, r 2 = 0.996, n = 12), respectively. Moreover, 90Y-derived water ages in a community water system (6.8 × 10 4 m 3 d –1 capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.« less

Using naturally occurring radionuclides to determine drinking water age in a community water system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Waples, James T.; Bordewyk, Jason K.; Knesting, Kristina M.

Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of 90Y/ 90Sr and 234Th/ 238U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (σ est: ± 3.8 h, P < 0.0001, r 2more » = 0.998, n = 11) and 25 days old (σ est: ± 13.3 h, P < 0.0001, r 2 = 0.996, n = 12), respectively. Moreover, 90Y-derived water ages in a community water system (6.8 × 10 4 m 3 d –1 capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.« less

An Evaluation Tool for CONUS-Scale Estimates of Components of the Water Balance

NASA Astrophysics Data System (ADS)

Saxe, S.; Hay, L.; Farmer, W. H.; Markstrom, S. L.; Kiang, J. E.

2016-12-01

Numerous research groups are independently developing data products to represent various components of the water balance (e.g. runoff, evapotranspiration, recharge, snow water equivalent, soil moisture, and climate) at the scale of the conterminous United States. These data products are derived from a range of sources, including direct measurement, remotely-sensed measurement, and statistical and deterministic model simulations. An evaluation tool is needed to compare these data products and the components of the water balance they contain in order to identify the gaps in the understanding and representation of continental-scale hydrologic processes. An ideal tool will be an objective, universally agreed upon, framework to address questions related to closing the water balance. This type of generic, model agnostic evaluation tool would facilitate collaboration amongst different hydrologic research groups and improve modeling capabilities with respect to continental-scale water resources. By adopting a comprehensive framework to consider hydrologic modeling in the context of a complete water balance, it is possible to identify weaknesses in process modeling, data product representation and regional hydrologic variation. As part of its National Water Census initiative, the U.S. Geological survey is facilitating this dialogue to developing prototype evaluation tools.

Impact of animal waste application on runoff water quality in field experimental plots.

PubMed

Hill, Dagne D; Owens, William E; Tchoounwou, Paul B

2005-08-01

Animal waste from dairy and poultry operations is an economical and commonly used fertilizer in the state of Louisiana. The application of animal waste to pasture lands not only is a source of fertilizer, but also allows for a convenient method of waste disposal. The disposal of animal wastes on land is a potential nonpoint source of water degradation. Water degradation and human health is a major concern when considering the disposal of large quantities of animal waste. The objective of this research was to determine the effect of animal waste application on biological (fecal coliform, Enterobacter spp. and Escherichia coli) and physical/chemical (temperature, pH, nitrate nitrogen, ammonia nitrogen, phosphate, copper, zinc, and sulfate) characteristics of runoff water in experimental plots. The effects of the application of animal waste have been evaluated by utilizing experimental plots and simulated rainfall events. Samples of runoff water were collected and analyzed for fecal coliforms. Fecal coliforms isolated from these samples were identified to the species level. Chemical analysis was performed following standard test protocols. An analysis of temperature, ammonia nitrogen, nitrate nitrogen, iron, copper, phosphate, potassium, sulfate, zinc and bacterial levels was performed following standard test protocols as presented in Standard Methods for the Examination of Water and Wastewater [1]. In the experimental plots, less time was required in the tilled broiler litter plots for the measured chemicals to decrease below the initial pre-treatment levels. A decrease of over 50% was noted between the first and second rainfall events for sulfate levels. This decrease was seen after only four simulated rainfall events in tilled broiler litter plots whereas broiler litter plots required eight simulated rainfall events to show this same type of reduction. A reverse trend was seen in the broiler litter plots and the tilled broiler plots for potassium. Bacteria numbers present after the simulated rainfall events were above 200/100 ml of sample water. It can be concluded that: 1) non-point source pollution has a significant effect on bacterial and nutrients levels in runoff water and in water resources; 2) land application of animal waste for soil fertilization makes a significant contribution to water pollution; 3) the use of tilling can significantly reduce the amount of nutrients available in runoff water.

Impact of Animal Waste Application on Runoff Water Quality in Field Experimental Plots

PubMed Central

Hill, Dagne D.; Owens, William E.; Tchounwou, Paul B.

2005-01-01

Animal waste from dairy and poultry operations is an economical and commonly used fertilizer in the state of Louisiana. The application of animal waste to pasture lands not only is a source of fertilizer, but also allows for a convenient method of waste disposal. The disposal of animal wastes on land is a potential nonpoint source of water degradation. Water degradation and human health is a major concern when considering the disposal of large quantities of animal waste. The objective of this research was to determine the effect of animal waste application on biological (fecal coliform, Enterobacter spp. and Escherichia coli) and physical/chemical (temperature, pH, nitrate nitrogen, ammonia nitrogen, phosphate, copper, zinc, and sulfate) characteristics of runoff water in experimental plots. The effects of the application of animal waste have been evaluated by utilizing experimental plots and simulated rainfall events. Samples of runoff water were collected and analyzed for fecal coliforms. Fecal coliforms isolated from these samples were identified to the species level. Chemical analysis was performed following standard test protocols. An analysis of temperature, ammonia nitrogen, nitrate nitrogen, iron, copper, phosphate, potassium, sulfate, zinc and bacterial levels was performed following standard test protocols as presented in Standard Methods for the Examination of Water and Wastewater [1]. In the experimental plots, less time was required in the tilled broiler litter plots for the measured chemicals to decrease below the initial pre-treatment levels. A decrease of over 50% was noted between the first and second rainfall events for sulfate levels. This decrease was seen after only four simulated rainfall events in tilled broiler litter plots whereas broiler litter plots required eight simulated rainfall events to show this same type of reduction. A reverse trend was seen in the broiler litter plots and the tilled broiler plots for potassium. Bacteria numbers present after the simulated rainfall events were above 200/100 ml of sample water. It can be concluded that: 1) non-point source pollution has a significant effect on bacterial and nutrients levels in runoff water and in water resources; 2) land application of animal waste for soil fertilization makes a significant contribution to water pollution; 3) the use of tilling can significantly reduce the amount of nutrients available in runoff water. PMID:16705834

EVALUATING THE EFFECTS OF UPSTREAM DISCHARGERS ON DOWNSTREAM WATER SUPPLIES: A SOURCE WATER PROTECTION MODEL

EPA Science Inventory

Source water protection is a component of the 1996 Amendments to the Safe Drinking Water Act. Drinking water utilities have adopted widely different philosophies for source water protection. the City of New York, with large upland water reservoirs, is investing millions of doll...

Water quality risks of 'improved' water sources: evidence from Cambodia.

PubMed

Shaheed, A; Orgill, J; Ratana, C; Montgomery, M A; Jeuland, M A; Brown, J

2014-02-01

The objective of this study was to investigate the quality of on-plot piped water and rainwater at the point of consumption in an area with rapidly expanding coverage of 'improved' water sources. Cross-sectional study of 914 peri-urban households in Kandal Province, Cambodia, between July-August 2011. We collected data from all households on water management, drinking water quality and factors potentially related to post-collection water contamination. Drinking water samples were taken directly from a subsample of household taps (n = 143), stored tap water (n = 124), other stored water (n = 92) and treated stored water (n = 79) for basic water quality analysis for Escherichia coli and other parameters. Household drinking water management was complex, with different sources used at any given time and across seasons. Rainwater was the most commonly used drinking water source. Households mixed different water sources in storage containers, including 'improved' with 'unimproved' sources. Piped water from taps deteriorated during storage (P < 0.0005), from 520 cfu/100 ml (coefficient of variation, CV: 5.7) E. coli to 1100 cfu/100 ml (CV: 3.4). Stored non-piped water (primarily rainwater) had a mean E. coli count of 1500 cfu/100 ml (CV: 4.1), not significantly different from stored piped water (P = 0.20). Microbial contamination of stored water was significantly associated with observed storage and handling practices, including dipping hands or receptacles in water (P < 0.005), and having an uncovered storage container (P = 0.052). The microbial quality of 'improved' water sources in our study area was not maintained at the point of consumption, possibly due to a combination of mixing water sources at the household level, unsafe storage and handling practices, and inadequately treated piped-to-plot water. These results have implications for refining international targets for safe drinking water access as well as the assumptions underlying global burden of disease estimates, which posit that 'improved' sources pose minimal risks of diarrhoeal diseases. © 2013 John Wiley & Sons Ltd.

Integrated Tsunami Database: simulation and identification of seismic tsunami sources, 3D visualization and post-disaster assessment on the shore

NASA Astrophysics Data System (ADS)

Krivorot'ko, Olga; Kabanikhin, Sergey; Marinin, Igor; Karas, Adel; Khidasheli, David

2013-04-01

One of the most important problems of tsunami investigation is the problem of seismic tsunami source reconstruction. Non-profit organization WAPMERR (http://wapmerr.org) has provided a historical database of alleged tsunami sources around the world that obtained with the help of information about seaquakes. WAPMERR also has a database of observations of the tsunami waves in coastal areas. The main idea of presentation consists of determining of the tsunami source parameters using seismic data and observations of the tsunami waves on the shore, and the expansion and refinement of the database of presupposed tsunami sources for operative and accurate prediction of hazards and assessment of risks and consequences. Also we present 3D visualization of real-time tsunami wave propagation and loss assessment, characterizing the nature of the building stock in cities at risk, and monitoring by satellite images using modern GIS technology ITRIS (Integrated Tsunami Research and Information System) developed by WAPMERR and Informap Ltd. The special scientific plug-in components are embedded in a specially developed GIS-type graphic shell for easy data retrieval, visualization and processing. The most suitable physical models related to simulation of tsunamis are based on shallow water equations. We consider the initial-boundary value problem in Ω := {(x,y) ?R2 : x ?(0,Lx ), y ?(0,Ly ), Lx,Ly > 0} for the well-known linear shallow water equations in the Cartesian coordinate system in terms of the liquid flow components in dimensional form Here ?(x,y,t) defines the free water surface vertical displacement, i.e. amplitude of a tsunami wave, q(x,y) is the initial amplitude of a tsunami wave. The lateral boundary is assumed to be a non-reflecting boundary of the domain, that is, it allows the free passage of the propagating waves. Assume that the free surface oscillation data at points (xm, ym) are given as a measured output data from tsunami records: fm(t) := ? (xm, ym,t), (xm,ym ) ?Ω, t ?(Tm1, Tm2), m = 1,2,...,M, M ?N (2) The problem of tsunami source reconstruction (inverse tsunami problem) consists of determining the unknown initial perturbation q(x,y) of the free surface defied in (1) from knowledge of the free surface oscillation data fm(t) given by (2). We present a numerical method to determine the tsunami source using measurements of the height of a passing tsunami wave. Proposed approach based on the weak solution theory for hyperbolic PDEs and adjoint problem method for minimization of the corresponding cost functional 2 J(q) = ?Aq - F? , F = (f1,...,fM ). (3) The adjoint problem is defined to obtain an explicit gradient formula for the cost functional (3). Different numerical algorithms (finite-difference approach and finite volume method) are proposed for the direct as well as adjoint problem. Conjugate gradient algorithm based on explicit gradient formula is used for numerical solution of the inverse problem (1)-(2). This work was partially supported by the Russian Foundation for Basic Research (project No. 12-01-00773) and by SB RAS interdisciplinary project 14 "Inverse Problems and Applications: Theory, Algorithms, Software".

Unconfined aquifer response to infiltration basins and shallow pump tests

NASA Astrophysics Data System (ADS)

Ostendorf, David W.; DeGroot, Don J.; Hinlein, Erich S.

2007-05-01

SummaryWe measure and model the unsteady, axisymmetric response of an unconfined aquifer to delayed, arbitrary recharge. Water table drainage follows the initial elastic aquifer response, as modeled for uniform, instantaneous recharge by Zlotnik and Ledder [Zlotnik, V., Ledder, G., 1992. Groundwater flow in a compressible unconfined aquifer with uniform circular recharge. Water Resources Research 28(6), 1619-1630] and delayed drainage by Moench [Moench, A.F., 1995. Combining the Neuman and Boulton models for flow to a well in an unconfined aquifer. Ground Water 33(3), 378-384]. We extend their analyses with a convolution integral that models the delayed response of an aquifer to infiltration from a circular infiltration basin. The basin routes the hydrograph to the water table with a decay constant dependent on a Brooks and Corey [Brooks, R.H., Corey, A.T., 1966. Properties of porous media affecting fluid flow. Journal of the Irrigation and Drainage Division ASCE 92(2), 61-88] unsaturated permeability exponent. The resulting closed form model approaches Neuman's [Neuman, S.P., 1972. Theory of flow in unconfined aquifers considering delayed response of the water table. Water Resources Research 8(4), 1031-1045] partially penetrating pump test equation for a small source radius, instantaneous, uniform drainage and a shallow screen section. Irrigation pump data at a well characterized part of the Plymouth-Carver Aquifer in southeastern Massachusetts calibrate the small source model, while infiltration data from the closed drainage system of State Route 25 calibrate the infiltration basin model. The calibrated permeability, elasticity, specific yield, and permeability exponent are plausible and consistent for the pump and infiltration data sets.

Microbial pathogens in source and treated waters from drinking water treatment plants in the United States and implications for human health

USGS Publications Warehouse

King, Dawn N.; Donohue, Maura J.; Vesper, Stephen J.; Villegas, Eric N.; Ware, Michael W.; Vogel, Megan E.; Furlong, Edward; Kolpin, Dana W.; Glassmeyer, Susan T.; Pfaller, Stacy

2016-01-01

An occurrence survey was conducted on selected pathogens in source and treated drinking water collected from 25 drinking water treatment plants (DWTPs) in the United States. Water samples were analyzed for the protozoa Giardia and Cryptosporidium (EPA Method 1623); the fungi Aspergillus fumigatus, Aspergillus niger and Aspergillus terreus (quantitative PCR [qPCR]); and the bacteria Legionella pneumophila (qPCR), Mycobacterium avium, M. avium subspecies paratuberculosis, and Mycobacterium intracellulare (qPCR and culture). Cryptosporidium and Giardia were detected in 25% and in 46% of the source water samples, respectively (treated waters were not tested). Aspergillus fumigatus was the most commonly detected fungus in source waters (48%) but none of the three fungi were detected in treated water. Legionella pneumophila was detected in 25% of the source water samples but in only 4% of treated water samples. M. avium and M. intracellulare were both detected in 25% of source water, while all three mycobacteria were detected in 36% of treated water samples. Five species of mycobacteria, Mycobacterium mucogenicum, Mycobacterium phocaicum, Mycobacterium triplex, Mycobacterium fortuitum, and Mycobacterium lentiflavum were cultured from treated water samples. Although these DWTPs represent a fraction of those in the U.S., the results suggest that many of these pathogens are widespread in source waters but that treatment is generally effective in reducing them to below detection limits. The one exception is the mycobacteria, which were commonly detected in treated water, even when not detected in source waters.

Impediments and constraints in the uptake of water sensitive urban design measures in greenfield and infill developments.

PubMed

Sharma, Ashok K; Cook, Stephen; Tjandraatmadja, Grace; Gregory, Alan

2012-01-01

Water sensitive urban developments are designed with integrated urban water management concepts and water sensitive urban design measures. The initiatives that may be included are the substitution of imported drinking water with alternative sources using a fit-for-purpose approach and structural and non-structural measures for the source control of stormwater. A water sensitive approach to urban development can help in achieving sustainability objectives by minimising disturbance to ecological and hydrological processes, and also relieve stress on conventional water systems. Water sensitive urban developments remain novel in comparison with conventional approaches, so the understanding and knowledge of the systems in regards to their planning; design; implementation; operation and maintenance; health impacts and environmental impacts is still developing and thus the mainstream uptake of these approaches faces many challenges. A study has been conducted to understand these challenges through a detailed literature review, investigating a large number of local greenfield and infill developments, and conducting extensive consultation with water professionals. This research has identified the social, economic, political, institutional and technological challenges faced in implementing water sensitive urban design in greenfield and infill developments. The research found in particular that there is the need for long-term monitoring studies of water sensitive urban developments. This monitoring is important to validate the performance of novel approaches implemented and improve associated guidelines, standards, and regulatory and governance frameworks, which can lead to mainstream acceptance of water sensitive urban development approaches. The dissemination of this research will help generate awareness among water professionals, water utilities, developers, planners and regulators of the research challenges to be addressed in order to achieve more mainstream acceptance of water sensitive approaches to urban development. This study is based on existing water sensitive urban developments in Australia, however, the methodology adopted in investigating impediments to the uptake of these developments can be applied globally. It is hoped that insights from this study will benefit water professionals in other countries where there is also a move towards water sensitive urban development.

Bacteriological and physico-chemical quality of drinking water sources in a rural community of Ethiopia.

PubMed

Tsega, N; Sahile, S; Kibret, M; Abera, B

2013-12-01

Accesses to safe water is a universal need however, many of the world's population lack access to adequate and safe water. Consumption of water contaminated causes health risk to the public and the situation is serous in rural areas. To assess the bacteriological and physico-chemical quality of drinking water sources in a rural community of Ethiopia. Water samples were collected from tap, open springs, open dug wells and protected springs for bacteriological analysis of total coliforms and thermotolerant coliforms. The turbidity, pH and temperature were measured immediately after collection. Most drinking water sources were found to have coliform counts above the recommended national and international guidelines and had high sanitary risk scores. There was a statistically significant difference among water sources with respect to TC and TTC (p < 0.05) and there was a statistically significant positive correlation between coliform counts and sanitary risk scores (p < 0.01). Most water sources didn't satisfy the turbidity values recommended by WHO. The water sources were heavily contaminated which suggested poor protection and sanitation practice in the water sources. Source protection strategies as well as monitoring are recommend for this community.

Geochemical evolution of groundwater in the Western Delta region of River Godavari, Andhra Pradesh, India

NASA Astrophysics Data System (ADS)

Nageswara Rao, P. V.; Appa Rao, S.; Subba Rao, N.

2017-05-01

The present study on geochemical evolution of groundwater is taken up to assess the controlling processes of water chemistry in the Western Delta region of the River Godavari (Andhra Pradesh), which is one of the major rice-producing centers in India. The study region is underlain by coarse sand with black clay (buried channels), black silty clay of recent origin (floodplain) and gray/white fine sand of modern beach sediment of marine source (coastal zone), including brown silty clay with fine sand (paleo-beach ridges). Groundwater is mostly brackish and very hard. It is characterized by Na+ > Mg2+ > Ca2+:HCO3 - > Cl- > SO4 2- > NO3 -, Na+ > Mg2+ > Ca2+:Cl- > HCO3 - > SO4 2-, and Mg2+ > Na+ > Ca2+ > or < K+:HCO3 - > Cl- > or > SO4 2- facies. The ionic relations (Ca2+ + Mg2+:HCO3 -, Ca2+ + Mg2+:SO4 2- + HCO3 -, Na+ + K+:TC, Na+ + K+:Cl- + SO4 2-, HCO3 -:TC, HCO3 -:Ca2+ + Mg2+, Na+:Cl- and Na+:Ca2+) indicate that the rock weathering, mineral dissolution, evaporation and ion exchange are the processes to control the aquifer chemistry. Anthropogenic and marine sources are also the supplementary factors for brackish water quality. These observations are further supported by Gibbs mechanisms that control the water chemistry. Thus, the study suggests that the initial quality of groundwater of geogenic origin has been subsequently modified by the influences of anthropogenic and marine sources.

Assessment of bioavailable fraction of POPS in surface water bodies in Johannesburg City, South Africa, using passive samplers: an initial assessment.

PubMed

Amdany, Robert; Chimuka, Luke; Cukrowska, Ewa; Kukučka, Petr; Kohoutek, Jiří; Tölgyessy, Peter; Vrana, Branislav

2014-09-01

In this study, the semipermeable membrane device (SPMD) passive samplers were used to determine freely dissolved concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in selected water bodies situated in and around Johannesburg City, South Africa. The devices were deployed for 14 days at each sampling site in spring and summer of 2011. Time weighted average (TWA) concentrations of the water-borne contaminants were calculated from the amounts of analytes accumulated in the passive samplers. In the area of interest, concentrations of analytes in water ranged from 33.5 to 126.8 ng l(-1) for PAHs, from 20.9 to 120.9 pg l(-1) for PCBs and from 0.2 to 36.9 ng l(-1) for OCPs. Chlorinated pesticides were mainly composed of hexachlorocyclohexanes (HCHs) (0.15-36.9 ng l(-1)) and dichlorodiphenyltrichloromethane (DDT) with its metabolites (0.03-0.55 ng l(-1)). By applying diagnostic ratios of certain PAHs, identification of possible sources of the contaminants in the various sampling sites was performed. These ratios were generally inclined towards pyrogenic sources of pollution by PAHs in all study sites except in the Centurion River (CR), Centurion Lake (CL) and Airport River (AUP) that indicated petrogenic origins. This study highlights further need to map up the temporal and spatial variations of these POPs using passive samplers.

PRESENTED 04/05/2006: MERCURY MEASUREMENTS ...

EPA Pesticide Factsheets

While traditional methods for determining mercury in solid samples involve the use of aggressive chemicals to dissolve the matrix and the use of other chemicals to properly reduce the mercury to the volatile elemental form, pyrolysis-based analyzers can be used by directly weighing the solid in a sampling boat and initiating the instrumental analysis for total mercury. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are the various research projects being performed in support of this Task and more in-depth coverage of each project. Briefly, each project's objective is stated below.Subtask 1: To integrate state-of-the-art technologies (polar organic chemical integrative samplers, advanced solid-phase extraction methodologies with liquid chromatography/electrospray/mass spectrometry) and apply them to studying the sources and fate of a select list of PPCPs. Application and improvement of analytical methodologies that can detect non-volatile, polar, water-soluble pharmaceuticals in source waters at levels that could be environmentally significant (at concentrations less than parts per billion, ppb). IAG with USGS ends in FY05. APM 20 due in FY05.Subtask 2: Coordination of interagency research and public outreach activities for PPCPs. Participate on NSTC Health and Environment subcommittee wo

TELEPHONIC PRESENTATION: MERCURY ...

EPA Pesticide Factsheets

While traditional methods for determining mercury in solid samples involve the use of aggressive chemicals to dissolve the matrix and the use of other chemicals to properly reduce the mercury to the volatile elemental form, pyrolysis-based analyzers can be used by directly weighing the solid in a sampling boat and initiating the instrumental analysis for total mercury. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are the various research projects being performed in support of this Task and more in-depth coverage of each project. Briefly, each project's objective is stated below.Subtask 1: To integrate state-of-the-art technologies (polar organic chemical integrative samplers, advanced solid-phase extraction methodologies with liquid chromatography/electrospray/mass spectrometry) and apply them to studying the sources and fate of a select list of PPCPs. Application and improvement of analytical methodologies that can detect non-volatile, polar, water-soluble pharmaceuticals in source waters at levels that could be environmentally significant (at concentrations less than parts per billion, ppb). IAG with USGS ends in FY05. APM 20 due in FY05.Subtask 2: Coordination of interagency research and public outreach activities for PPCPs. Participate on NSTC Health and Environment subcommittee wo

Source identification and fish exposure for polychlorinated biphenyls using congener analysis from passive water samplers in the Millers River basin, Massachusetts

USGS Publications Warehouse

Colman, John A.

2001-01-01

Measurements of elevated concentrations of polychlorinated biphenyls (PCBs) in fish and in streambed sediments of the Millers River Basin, Massachusetts and New Hampshire, have been reported without evidence of the PCB source. In 1999, an investigation was initiated to determine the source(s) of the elevated PCB concentrations observed in fish and to establish the extent of fish exposure to PCBs along the entire main stems of the Millers River and one of its tributaries, the Otter River. Passive samplers deployed for 2-week intervals in the water-column at 3 1 stations, during summer and fall 1999, were used to assess PCB concentrations in the Millers River Basin. The samplers concentrate PCBs, which diffuse from the water column through a polyethylene membrane to hexane (0.200 liters) contained inside the samplers. Only dissolved PCBs (likely equivalent to the bioavailable fraction) are subject to diffusion through the membrane. The summed concentrations of all targeted PCB congeners (summed PCB) retrieved from the samplers ranged from 1 to 8,000 nanograms per hexane sample. Concentration and congener-pattern comparisons indicated that the historical release of PCBs in the Millers River Basin likely occurred on the Otter River at the upstream margin of Baldwinville, Mass. Elevated water-column concentrations measured in a wetland reach on the Otter River downstream from Baldwinville were compatible with a conceptual model for a present-day (1999) source in streambed sediments, to which the PCBs partitioned after their original introduction into the Otter River and from which PCBs are released to the water now that the original discharge has ceased or greatly decreased. Two four-fold decreases in summed PCB concentrations in the Millers River, by comparison with the highest concentration on the Otter River, likely were caused by (1) dilution with water from the relatively uncontaminated upstream Millers River and (2) volatilization of PCBs from the Millers River in steep-gradient reaches. A relatively constant concentration of summed PCBs in the reach of the Millers River from river mile 20 to river mile 10 was likely a consequence of a balance between decreased volatilization rates in that relatively low-gradient reach and resupply of PCBs to the water column from contaminated streambed sediments. A second high-gradient reach from river mile 10 to the confluence of the Millers River with the Connecticut River also was associated with a decrease in concentration of water-column summed PCBs. Volatilization as a loss mechanism was supported by evidence in the form of slight changes of the congener pattern in the reaches where decreases occurred. Exposure of fish food webs to concentrations of dissolved PCBs exceeded the U.S. Environmental Protection Agency's water-quality criterion for PCBs throughout most of the Millers River and Otter River main stems. Because the apparent source of PCBs discharged was upstream on the Otter River, a large number of river miles downstream (more than 30 mi) had summer water-column PCB concentrations that would likely lead to high concentrations of PCBs in fish.

Electrodeposition at room temperature of amorphous silicon and germanium nanowires in ionic liquid

NASA Astrophysics Data System (ADS)

Martineau, F.; Namur, K.; Mallet, J.; Delavoie, F.; Endres, F.; Troyon, M.; Molinari, M.

2009-11-01

The electrodeposition at room temperature of silicon and germanium nanowires from the air- and water-stable ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (P1,4) containing SiCl4 as Si source or GeCl4 as Ge source is investigated by cyclic voltammetry. By using nanoporous polycarbonate membranes as templates, it is possible to reproducibly grow pure silicon and germanium nanowires of different diameters. The nanowires are composed of pure amorphous silicon or germanium. The nanowires have homogeneous cylindrical shape with a roughness of a few nanometres on the wire surfaces. The nanowires' diameters and lengths well match with the initial membrane characteristics. Preliminary photoluminescence experiments exhibit strong emission in the near infrared for the amorphous silicon nanowires.

Atom Transfer Radical Polymerization of Functionalized Vinyl Monomers Using Perylene as a Visible Light Photocatalyst

PubMed Central

Theriot, Jordan C.; Ryan, Matthew D.; French, Tracy A.; Pearson, Ryan M.; Miyake, Garret M.

2016-01-01

A standardized technique for atom transfer radical polymerization of vinyl monomers using perylene as a visible-light photocatalyst is presented. The procedure is performed under an inert atmosphere using air- and water-exclusion techniques. The outcome of the polymerization is affected by the ratios of monomer, initiator, and catalyst used as well as the reaction concentration, solvent, and nature of the light source. Temporal control over the polymerization can be exercised by turning the visible light source off and on. Low dispersities of the resultant polymers as well as the ability to chain-extend to form block copolymers suggest control over the polymerization, while chain end-group analysis provides evidence supporting an atom-transfer radical polymerization mechanism. PMID:27166728

Revisiting streamside trees that do not use stream water: can the two water worlds hypothesis and snowpack isotopic effects explain a missing water source?: Riparian tree water sources

DOE PAGES

Bowling, David R.; Schulze, Emily S.; Hall, Steven J.

2016-10-14

We revisit a classic ecohydrological study that showed streamside riparian trees in a semiarid mountain catchment did not use perennial stream water. The original study suggested that mature individuals of Acer negundo, Acer grandidentatum, and other species were dependent on water from “deeper strata,” possibly groundwater. We used a dual stable isotope approach (δ 18O and δ 2H) to further examine the water sources of these trees. We tested the hypothesis that groundwater was the main tree water source, but found that neither groundwater nor stream water matched the isotope composition of xylem water during two growing seasons. Soil watermore » (0–1 m depth) was closest to and periodically overlapped with xylem water isotope composition, but overall, xylem water was isotopically enriched compared to all measured water sources. The “two water worlds” hypothesis postulates that soil water comprises isotopically distinct mobile and less mobile pools that do not mix, potentially explaining this disparity. We further hypothesized that isotopic effects during snowpack metamorphosis impart a distinct isotope signature to the less mobile soil water that supplies summer transpiration. Depth trends in water isotopes following snowmelt were consistent with the two water worlds hypothesis, but snow metamorphic isotope effects could not explain the highly enriched xylem water. Thus, the dual isotope approach did not unambiguously determine the water source(s) of these riparian trees. Further exploration of physical, geochemical, and biological mechanisms of water isotope fractionation and partitioning is necessary to resolve these data, highlighting critical challenges in the isotopic determination of plant water sources.« less

Revisiting streamside trees that do not use stream water: can the two water worlds hypothesis and snowpack isotopic effects explain a missing water source?: Riparian tree water sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bowling, David R.; Schulze, Emily S.; Hall, Steven J.

We revisit a classic ecohydrological study that showed streamside riparian trees in a semiarid mountain catchment did not use perennial stream water. The original study suggested that mature individuals of Acer negundo, Acer grandidentatum, and other species were dependent on water from “deeper strata,” possibly groundwater. We used a dual stable isotope approach (δ 18O and δ 2H) to further examine the water sources of these trees. We tested the hypothesis that groundwater was the main tree water source, but found that neither groundwater nor stream water matched the isotope composition of xylem water during two growing seasons. Soil watermore » (0–1 m depth) was closest to and periodically overlapped with xylem water isotope composition, but overall, xylem water was isotopically enriched compared to all measured water sources. The “two water worlds” hypothesis postulates that soil water comprises isotopically distinct mobile and less mobile pools that do not mix, potentially explaining this disparity. We further hypothesized that isotopic effects during snowpack metamorphosis impart a distinct isotope signature to the less mobile soil water that supplies summer transpiration. Depth trends in water isotopes following snowmelt were consistent with the two water worlds hypothesis, but snow metamorphic isotope effects could not explain the highly enriched xylem water. Thus, the dual isotope approach did not unambiguously determine the water source(s) of these riparian trees. Further exploration of physical, geochemical, and biological mechanisms of water isotope fractionation and partitioning is necessary to resolve these data, highlighting critical challenges in the isotopic determination of plant water sources.« less

Determinants of stunting among children aged 6-59 months at Kindo Didaye woreda, Wolaita Zone, Southern Ethiopia: Unmatched case control study

PubMed Central

Batiro, Bancha; Demissie, Tsegaye; Halala, Yoseph

2017-01-01

Background Stunting is a well-established risk marker of poor child development. Globally in 2017, 155 million children under 5 were estimated to be stunted. While different activities are being done to reduce the burden of stunted growth, the problem is overwhelming in Africa; it was increased by 24%. Therefore, identifying determinants of stunting among children aged 6–59 would help to set priorities for action and to the design of stunting reduction plan at a grassroots level. Methods The unmatched case-control study was conducted in randomly selected 8 rural kebeles of Kindo Didaye woreda, Ethiopia from February to April, 2016 to identify the determinants of stunting among children aged 6–59 months. The sampling frame was identified by enumeration of 6–59 months of age children in the entire households of the study area. From which 155 as cases and 310 as controls were chosen using anthropometric measurement based on the median of WHO 2006 reference population. The anthropometric data were analyzed by WHO Anthro 2010 software to generate Z-score values. Odds Ratio along with 95% confidence interval was estimated to identify determinants of stunting using the multivariable logistic regression. Results Drinking water from unsafe source (AOR = 7.06, 95% CI; 4.40–20.42),occasionally eating animal source food (AOR = 0.51, 95% CI; 0.02–0.68), ARI in the past two weeks (AOR = 3.04, (95% CI; 1.04–13.35), late initiation of breastfeeding after one hours after birth (AOR = 5.16, 95% CI; 2.24–15.90) and lack of vaccination (AOR = 6.38, 95% CI; 2.54–17.10)were significantly associated with stunting. Conclusions Factors like exposure to diarrhea disease, exposure to acute respiratory infection, late initiation of breast milk after child breath, squeeze out of 1st breast milk, lack of vaccination, animal source of food, and unsafe source of water for drinking could be used to set priorities for action and to the design of Kindo Didaye woreda plan for stunting reduction down to grassroots level. Therefore, zonal health department and Kindo Didaye woreda health office should promote the importance of colostrums feeding. Drinking water should be decontaminated. Expansion of vaccination program to enhance herd immunity at the community level is important. PMID:29261680

Pharmaceuticals and endocrine disrupting compounds in U.S. drinking water.

PubMed

Benotti, Mark J; Trenholm, Rebecca A; Vanderford, Brett J; Holady, Janie C; Stanford, Benjamin D; Snyder, Shane A

2009-02-01

The drinking water for more than 28 million people was screened for a diverse group of pharmaceuticals, potential endocrine disrupting compounds (EDCs), and other unregulated organic contaminants. Source water, finished drinking water, and distribution system (tap) water from 19 U.S. water utilities was analyzed for 51 compounds between 2006 and 2007. The 11 most frequently detected compounds were atenolol, atrazine, carbamazepine, estrone, gemfibrozil, meprobamate, naproxen, phenytoin, sulfamethoxazole, TCEP, and trimethoprim. Median concentrations of these compounds were less than 10 ng/L, except for sulfamethoxazole in source water (12 ng/L), TCEP in source water (120 ng/L), and atrazine in source, finished, and distribution system water (32, 49, and 49 ng/L). Atrazine was detected in source waters far removed from agricultural application where wastewater was the only known source of organic contaminants. The occurrence of compounds in finished drinking water was controlled by the type of chemical oxidation (ozone or chlorine) used at each plant. At one drinking water treatment plant, summed monthly concentrations of the detected analytes in source and finished water are reported. Atenolol, atrazine, DEET, estrone, meprobamate, and trimethoprim can serve as indicator compounds representing potential contamination from other pharmaceuticals and EDCs and can gauge the efficacy of treatment processes.

Hydrologic Geospatial Fabric as Community Cyberinfrastructure: International standardization best practices and the U.S. Open Water Data Initiative implementation.

NASA Astrophysics Data System (ADS)

Blodgett, D. L.

2016-12-01

Recent prolonged droughts, catastrophic flooding, and the need to protect and restore aquatic ecosystems, has increased the emphasis on information sharing in the water resources science and engineering domains. Internationally the joint World Meteorological Organization (WMO) and Open Geospatial Consortium (OGC) Hydrology Domain Working Group (HDWG) has been working toward a comprehensive system of standards and best practices for the Hydrology Domain. In the U.S. the multi-agency led and open to all U.S. Advisory Committee on Water Information (ACWI) was tasked to implement an Open Water Data Initiative (OWDI), "that will integrate currently fragmented water information into a connected, national water data framework"[1]. The status of both will be presented with focus on a community hydrologic geospatial fabric. Hydrology observations data standardization was the emphasis of the first 5 years of the HDWG. This work included WaterML 2.0 parts 1 - timeseries and part 2 - ratings and gagings. In 2016, the first of two new hydrographic feature models, GroundwaterML2, was completed and the second, for surface water features, was in active development. The WMO Commission for Hydrology is considering adoption of all these standards and their adoption is central to the U.S. OWDI. OWDI participants have produced a special collection in the Journal of American Water Resources Association and several initiative working groups have concluded their activities. One early deliverable from the OWDI was a new easier to use structure for the NHDPlus dataset. Building on this, a project to create a national Network Linked Data Index (NLDI) is being undertaken as an open-source community endeavor. The NLDI centralizes river network data, network navigation tools, crawlers that index data to the network, and utilities to register or remove data from the network. Research that informed the design of the NLDI will be presented along with recent development and findings of the project. This specific activity will be put in the context of the methods for and status of international standards and best practices development intended to help realize such national and international goals. [1] http://acwi.gov/spatial/open_water_data_charge_to_fgdc_june23_2014.pdf

[Water sources of Nitraria sibirica and response to precipitation in two desert habitats].

PubMed

Zhou, Hai; Zhao, Wen Zhi; He, Zhi Bin

2017-07-18

Nitraria sibirica usually exists in a form of nebkhas, and has strong ecological adaptability. The plant species has distinctive function for wind prevention and sand fixation, and resistance drought and salt. However, the water condition is still a limiting factor for the plant survival and development. In order to understand the water use strategy of the plant in different desert habitats, we selected the N. sibirica growing in sandy desert habitat and gravel desert habitat to study the seaso-nal variation of plant water sources and response to precipitation at the edge of the oasis of Linze in the Hexi Corridor. We measured the oxygen stable isotope of the plant stem water and the different potential water sources (precipitation, soil water and ground water), and used the IsoSource model to calculate the proportion of water sources from the potential water. The results showed that there were significant seasonal variation characteristics of δ 18 O value and water source of stem water for the plant in the two habitats. In the sandy habitat, the plant used more ground water in the less precipitation seasons including spring and fall, and more than 50% of the water sources absorbed from ground water. However, under the condition of gravel habitat, the plant could not achieve the ground water level depth of 11.5 m, and its water source was controlled by precipitation, which had large seasonal variability. The water sources of N. sibirica had significant responses to the change of precipitation in the two desert habitats. Following the rapid decrease of soil water content after the precipitation events, the plant in the sandy habitat turned to use the abundant ground water as the main sources of water, while the plant in the gravel habitat only used the less water from precipita-tion infiltration to the deep soil. Therefore, different water use strategies of the plant in the two habitats were the main reason for the difference in growth characteristics, and it had a strong ability of self-adjustment and adaptation.

Relative benefits of on-plot water supply over other 'improved' sources in rural Vietnam.

PubMed

Brown, Joe; Hien, Vo Thi; McMahan, Lanakila; Jenkins, Marion W; Thie, Lauren; Liang, Kaida; Printy, Erin; Sobsey, Mark D

2013-01-01

Access to improved water sources is rapidly expanding in rural central Vietnam. We examined one NGO-led piped water supply programme to assess the drinking water quality and health impacts of piped water systems where access to 'improved' water sources is already good. This longitudinal, prospective cohort study followed 300 households in seven project areas in Da Nang province, Vietnam: 224 households who paid for an on-plot piped water connection and 76 control households from the same areas relying primarily on 'improved' water sources outside the home. The 4-month study was intended to measure the impact of the NGO-led water programmes on households' drinking water quality and health and to evaluate system performance. We found that: (i) households connected to a piped water supply had consistently better drinking water quality than those relying on other sources, including 'improved' sources and (ii) connected households experienced less diarrhoea than households without a piped water connection (adjusted longitudinal prevalence ratio: 0.57 (95% CI 0.39-0.86, P = 0.006) and households using an 'improved' source not piped to the plot: (adjusted longitudinal prevalence ratio: 0.59 (95% CI 0.39-0.91, P = 0.018). Our results suggest that on-plot water service yields benefits over other sources that are considered 'improved' by the WHO/UNICEF Joint Monitoring Programme. © 2012 Blackwell Publishing Ltd.

Tracing water sources of terrestrial animal populations with stable isotopes: laboratory tests with crickets and spiders.

PubMed

McCluney, Kevin E; Sabo, John L

2010-12-31

Fluxes of carbon, nitrogen, and water between ecosystem components and organisms have great impacts across levels of biological organization. Although much progress has been made in tracing carbon and nitrogen, difficulty remains in tracing water sources from the ecosystem to animals and among animals (the "water web"). Naturally occurring, non-radioactive isotopes of hydrogen and oxygen in water provide a potential method for tracing water sources. However, using this approach for terrestrial animals is complicated by a change in water isotopes within the body due to differences in activity of heavy and light isotopes during cuticular and transpiratory water losses. Here we present a technique to use stable water isotopes to estimate the mean mix of water sources in a population by sampling a group of sympatric animals over time. Strong correlations between H and O isotopes in the body water of animals collected over time provide linear patterns of enrichment that can be used to predict a mean mix of water sources useful in standard mixing models to determine relative source contribution. Multiple temperature and humidity treatment levels do not greatly alter these relationships, thus having little effect on our ability to estimate this population-level mix of water sources. We show evidence for the validity of using multiple samples of animal body water, collected across time, to estimate the isotopic mix of water sources in a population and more accurately trace water sources. The ability to use isotopes to document patterns of animal water use should be a great asset to biologists globally, especially those studying drylands, droughts, streamside areas, irrigated landscapes, and the effects of climate change.

Holistic Watershed-Scale Approach for Studying Agricultural Chemicals

NASA Astrophysics Data System (ADS)

Capel, P. D.; Domagalski, J. L.

2006-05-01

The USGS National Water-Quality Assessment (NAWQA) Program studied the water quality of 51 areas across the United States during its first decade (1991-2001). Analyses of results from that phase of the NAWQA Program indicated that detailed studies of the processes affecting water quality could aid in the interpretation of these data, help to determine the direction and scope of future monitoring studies, and add to the understanding of the sources, transport and fate of non-point source chemicals, such as from agriculture. Now in the second decade of investigations, the NAWQA Program has initiated new process-based detailed studies to increase our understanding at the scale of a small watershed (about 3-15 square kilometers), nested within the larger basins studied during the first decade. The holistic, mass-budget approach for small agricultural watersheds that was adopted includes processes, and measures water and chemicals in the atmosphere, surface water, tile drains, overland flow, and within various sub-surface environments including the vadose, saturated, and hyporheic zones. The primary chemicals of interest were nutrients (nitrogen and phosphorous), the triazine and acetanilide herbicides, and the organophosphorus insecticides. Extensive field observations were made, and numerical models were developed to simulate important environmental compartments and interfaces associated with the transport and fate of agricultural chemicals. It is well recognized that these field measurements and simulations cannot fully achieve a full mass budget at this scale, but the approach provides a useful means for comparisons of various processes in different environmental settings. The results gained using this approach will add to the general knowledge of environmental transport and fate processes, and have transfer value to unstudied areas and different scales of investigation. The five initial study areas started in 2002, included watersheds in California, Indiana, Maryland, Nebraska and Washington. Two watersheds in Iowa and Mississippi were added in 2005. Each of these areas adopted the same general study design, but modified it slightly based on the local environmental setting. Consistent field and laboratory methods were used to enable direct comparison of results from each study area. This presentation of the study goals, design, and methods will serve as an introduction to other talks in this symposium.

Conducting Source Water Assessments

EPA Pesticide Factsheets

This page presents background information on the source water assessment steps, the four steps of a source wter assessment, and how to use the results of an assessment to protect drinking water sources.

The HYPE Open Source Community

NASA Astrophysics Data System (ADS)

Strömbäck, Lena; Arheimer, Berit; Pers, Charlotta; Isberg, Kristina

2013-04-01

The Hydrological Predictions for the Environment (HYPE) model is a dynamic, semi-distributed, process-based, integrated catchment model (Lindström et al., 2010). It uses well-known hydrological and nutrient transport concepts and can be applied for both small and large scale assessments of water resources and status. In the model, the landscape is divided into classes according to soil type, vegetation and altitude. The soil representation is stratified and can be divided in up to three layers. Water and substances are routed through the same flow paths and storages (snow, soil, groundwater, streams, rivers, lakes) considering turn-over and transformation on the way towards the sea. In Sweden, the model is used by water authorities to fulfil the Water Framework Directive and the Marine Strategy Framework Directive. It is used for characterization, forecasts, and scenario analyses. Model data can be downloaded for free from three different HYPE applications: Europe (www.smhi.se/e-hype), Baltic Sea basin (www.smhi.se/balt-hype), and Sweden (vattenweb.smhi.se) The HYPE OSC (hype.sourceforge.net) is an open source initiative under the Lesser GNU Public License taken by SMHI to strengthen international collaboration in hydrological modelling and hydrological data production. The hypothesis is that more brains and more testing will result in better models and better code. The code is transparent and can be changed and learnt from. New versions of the main code will be delivered frequently. The main objective of the HYPE OSC is to provide public access to a state-of-the-art operational hydrological model and to encourage hydrologic expertise from different parts of the world to contribute to model improvement. HYPE OSC is open to everyone interested in hydrology, hydrological modelling and code development - e.g. scientists, authorities, and consultancies. The HYPE Open Source Community was initiated in November 2011 by a kick-off and workshop with 50 eager participants from twelve different countries. In beginning of 2013 we will release a new version of the code featuring new and better modularization, corresponding to hydrological processes which will make the code easier to understand and further develop. During 2013 we also plan a new workshop and HYPE course for everyone interested in the community. Lindström, G., Pers, C.P., Rosberg, R., Strömqvist, J., Arheimer, B. 2010. Development and test of the HYPE (Hydrological Predictions for the Environment) model - A water quality model for different spatial scales. Hydrology Research 41.3-4:295-319

A Road Map for America's Water for the Next 20 Years

NASA Astrophysics Data System (ADS)

Lall, U.; Rising, J.; Ho, M. W.; Josset, L.; Allaire, M.; Troy, T.; Devineni, N.; Ruddell, B. L.; Pal, I.

2016-12-01

This talk will present a perspective from the America's Water Initiative team that has been discussing the past, present and future of water in America. Paleoclimate reconstructions reveal dramatic inter-annual to decadal structure in the variation in drought across America and provide a backdrop for increasing climate variability expected in the next century. At the same time our water infrastructure ranging from main pipes to dams is aging and in urgent need of renewal. Non-point source pollution from cities and agriculture continues to be a concern and poses a challenge for water supplies. At the same time, there has been progress on water use efficiency, and on the acceptability of water reuse. To assure water, energy and food security for the future, one needs significant investments in water infrastructure of all types, and the cumulative estimates for these run to nearly $3 trillion over the next 20 years. A discussion on infrastructure provision is not complete without a discussion on how use patterns (e.g., where and which crops are grown and how), economic and financial instruments (e.g., insurance associated with the failure of water supply or with flooding, water pricing and trading, capital for construction), regulatory instruments (e.g., standards and policies), technological innovation (e.g., in sensors to improve water utilization in agriculture or pervasive monitoring of drinking and environmental water quality, nanofiltration and resource extraction from waste streams), and governance of water systems. We present for discussion, a proposal for the next 5 and the next 20 years that lays out an adaptive strategy to apprach these issues, and the associated unknowns and challenges that we need to address. The America's Water initiative was launched by Columbia University in partnership with other Universities and representatives from the public and private sectors. A modeling platform that brings together climate, water, agricultural, energy and urban data from the continental USA at a county resolution, and allows the exploration of selected strategies and trade-offs has been developed, and we invite the research community to participate in the use and enhancement of this platform.

Coupled oxygen-carbon dioxide modelling to partition potential external contribution to stream carbon dioxide concentrations.

NASA Astrophysics Data System (ADS)

Butman, D. E.; Holtgrieve, G. W.

2017-12-01

Recent modelling studies in large catchments have estimated that in excess of 74% of the dissolved carbon dioxide found in first and second order streams originate from allochthonous sources. Stable isotopes of carbon-13 in carbon dioxide have been used to identify ground water seeps in stream systems, where decreases in δ13CO2 occur along gaining stream reaches, suggesting that carbon dioxide in ground water is more depleted than what is found in surface water due to fractionation of CO2 during emissions across the air water interface. Although isotopes represent a chemical tracer in stream systems for potential groundwater contribution, the temporal resolution of discrete samples make partitioning allochthonous versus autochthonous sources of CO2 difficult on hydrologically relevant time scales. Here we show results of field deployments of high frequent dissolved CO2, O2, PAR, Temperature and pH from the Thornton Creek Watershed, the largest urban watershed in Seattle, WA. We present an exploration into using high resolution time series of dissolved oxygen and carbon dioxide in a dual gas approach to separate the contribution of in stream respiration from external sources. We extend upon previous efforts to model stream metabolism across diel cycles by incorporating simultaneous direct measurements of dissolved oxygen, PCO2, and pH within an inverse modeling framework and Bayesian parameter estimation. With an initial assumption of a stoichiometric ratio of 1:1 for O2 and CO2 for autochthonous driven metabolism, we investigate positive or negative departures from this ratio as an indicator of external CO2 to the stream (terrestrial or atmospheric) and factors contributing to this flux.

An integrated modeling approach for estimating the water quality benefits of conservation practices at the river basin scale.

PubMed

Santhi, C; Kannan, N; White, M; Di Luzio, M; Arnold, J G; Wang, X; Williams, J R

2014-01-01

The USDA initiated the Conservation Effects Assessment Project (CEAP) to quantify the environmental benefits of conservation practices at regional and national scales. For this assessment, a sampling and modeling approach is used. This paper provides a technical overview of the modeling approach used in CEAP cropland assessment to estimate the off-site water quality benefits of conservation practices using the Ohio River Basin (ORB) as an example. The modeling approach uses a farm-scale model, Agricultural Policy Environmental Extender (APEX), and a watershed scale model (the Soil and Water Assessment Tool [SWAT]) and databases in the Hydrologic Unit Modeling for the United States system. Databases of land use, soils, land use management, topography, weather, point sources, and atmospheric depositions were developed to derive model inputs. APEX simulates the cultivated cropland, Conserve Reserve Program land, and the practices implemented on them, whereas SWAT simulates the noncultivated land (e.g., pasture, range, urban, and forest) and point sources. Simulation results from APEX are input into SWAT. SWAT routes all sources, including APEX's, to the basin outlet through each eight-digit watershed. Each basin is calibrated for stream flow, sediment, and nutrient loads at multiple gaging sites and turned in for simulating the effects of conservation practice scenarios on water quality. Results indicate that sediment, nitrogen, and phosphorus loads delivered to the Mississippi River from ORB could be reduced by 16, 15, and 23%, respectively, due to current conservation practices. Modeling tools are useful to provide science-based information for assessing existing conservation programs, developing future programs, and developing insights on load reductions necessary for hypoxia in the Gulf of Mexico. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Hydrocarbon Plume Dynamics in the Worldś Most Spectacular Hydrocarbon Seeps, Santa Barbara Channel, California

NASA Astrophysics Data System (ADS)

Mau, S.; Reed, J.; Clark, J.; Valentine, D.

2006-12-01

Large quantities of natural gas are emitted from the seafloor into the coastal ocean near Coal Oil Point, Santa Barbara Channel (SBC), California. Methane, ethane, and propane were quantified in the surface water at 79 stations in a 270 km2 area in order to map the surficial hydrocarbon plume and to quantify air-sea exchange of these gases. A time series was initiated for 14 stations to identify the variability of the mapped plume, and biologically-mediated oxidation rates of methane were measured to quantify the loss of methane in surface water. The hydrocarbon plume was found to comprise ~70 km2 and extended beyond study area. The plume width narrowed from 3 km near the source to 0.7 km further from the source, and then expanded to 6.7 km at the edge of the study area. This pattern matches the cyclonic gyre which is the normal current flow in this part of the Santa Barbara Channel - pushing water to the shore near the seep field and then broadening the plume while the water turns offshore further from the source. Concentrations of gaseous hydrocarbons decrease as the plume migrates. Time series sampling shows similar plume width and hydrocarbon concentrations when normal current conditions prevail. In contrast, smaller plume width and low hydrocarbon concentrations were observed when an additional anticyclonic eddy reversed the normal current flow, and a much broader plume with higher hydrocarbon concentrations was observed during a time of diminished speed within the current gyre. These results demonstrate that surface currents control hydrocarbon plume dynamics in the SBC, though hydrocarbon flux to the atmosphere is likely less dependent on currents. Estimates of air- sea hydrocarbon flux and biological oxidation rates will also be presented.

A geochemical approach to determine sources and movement of saline groundwater in a coastal aquifer.

PubMed

Anders, Robert; Mendez, Gregory O; Futa, Kiyoto; Danskin, Wesley R

2014-01-01

Geochemical evaluation of the sources and movement of saline groundwater in coastal aquifers can aid in the initial mapping of the subsurface when geological information is unavailable. Chloride concentrations of groundwater in a coastal aquifer near San Diego, California, range from about 57 to 39,400 mg/L. On the basis of relative proportions of major-ions, the chemical composition is classified as Na-Ca-Cl-SO4, Na-Cl, or Na-Ca-Cl type water. δ(2)H and δ(18)O values range from -47.7‰ to -12.8‰ and from -7.0‰ to -1.2‰, respectively. The isotopically depleted groundwater occurs in the deeper part of the coastal aquifer, and the isotopically enriched groundwater occurs in zones of sea water intrusion. (87)Sr/(86)Sr ratios range from about 0.7050 to 0.7090, and differ between shallower and deeper flow paths in the coastal aquifer. (3)H and (14)C analyses indicate that most of the groundwater was recharged many thousands of years ago. The analysis of multiple chemical and isotopic tracers indicates that the sources and movement of saline groundwater in the San Diego coastal aquifer are dominated by: (1) recharge of local precipitation in relatively shallow parts of the flow system; (2) regional flow of recharge of higher-elevation precipitation along deep flow paths that freshen a previously saline aquifer; and (3) intrusion of sea water that entered the aquifer primarily during premodern times. Two northwest-to-southeast trending sections show the spatial distribution of the different geochemical groups and suggest the subsurface in the coastal aquifer can be separated into two predominant hydrostratigraphic layers. © 2013, National Ground Water Association.

Phosphorus runoff from waste water treatment biosolids and poultry litter applied to agricultural soils.

PubMed

White, John W; Coale, Frank J; Sims, J Thomas; Shober, Amy L

2010-01-01

Differences in the properties of organic phosphorus (P) sources, particularly those that undergo treatment to reduce soluble P, can affect soil P solubility and P transport in surface runoff. This 2-yr field study investigated soil P solubility and runoff P losses from two agricultural soils in the Mid-Atlantic region after land application of biosolids derived from different waste water treatment processes and poultry litter. Phosphorus speciation in the biosolids and poultry litter differed due to treatment processes and significantly altered soil P solubility and dissolved reactive P (DRP) and bioavailable P (FeO-P) concentrations in surface runoff. Runoff total P (TP) concentrations were closely related to sediment transport. Initial runoff DRP and FeO-P concentrations varied among the different biosolids and poultry litter applied. Over time, as sediment transport declined and DRP concentrations became an increasingly important component of runoff FeO-P and TP, total runoff P was more strongly influenced by the type of biosolids applied. Throughout the study, application of lime-stabilized biosolids and poultry litter increased concentrations of soil-soluble P, readily desorbable P, and soil P saturation, resulting in increased DRP and FeO-P concentrations in runoff. Land application of biosolids generated from waste water treatment processes that used amendments to reduce P solubility (e.g., FeCl(3)) did not increase soil P saturation and reduced the potential for DRP and FeO-P transport in surface runoff. These results illustrate the importance of waste water treatment plant process and determination of specific P source coefficients to account for differential P availability among organic P sources.

Water-Use Estimates for West Virginia, 2004

USGS Publications Warehouse

Atkins, John T.

2007-01-01

This study estimates the quantity of surface water and ground water used within West Virginia. About 4,787 million gallons per day (Mgal/d) of water were withdrawn from West Virginia surface-water and ground-water sources in 2004, with about 4,641 Mgal/d (97 percent) from surface-water sources and about 146 Mgal/d (3 percent) from ground water sources. The largest surface-water withdrawals were in Grant and Mason Counties and were about 1,156 and 1,090 Mgal/d, respectively. The largest ground-water withdrawals were in Berkeley and Wood Counties and were about 12.0 and 12.8 Mgal/d, respectively. Estimates were determined for surface-water and ground-water withdrawals in seven water-use categories: public supply, domestic, thermoelectric power, industrial, irrigation, commercial, and mining. Instream water uses, including hydroelectric power generation, were not considered. Total withdrawals for public supply were 189 Mgal/d, of which 152 Mgal/d were from surface-water sources and 37 Mgal/d were from ground-water sources. Kanawha County withdrew 34 Mgal/d of surface water for public supply, which is more than any other county in the state. Wood County withdrew more ground water for public supply than any other county in the state, about 7.59 Mgal/d. The total domestic (non-publicly supplied) water withdrawal was estimated at 33.5 Mgal/d, with 98 percent from ground water and 2 percent from surface water. There were 17 fossil-fuel, steam-generating thermoelectric power plants operated in the state, 10 plants with once-through cooling systems and 7 plants with recirculation cooling systems. Thermoelectric power used the greatest amount of water compared to the other water-use categories, and water withdrawal from surface-water sources was about 3,406 Mgal/d for plants with once-through cooling systems and about 145 Mgal/d for plants with recirculation cooling systems. Only a trace of water was withdrawn from ground-water sources for plants with once-through cooling systems and about 0.20 Mgal/d for plants with recirculation cooling systems. Water withdrawal by industries was about 911 Mgal/d from surface-water sources and about 54 Mgal/d from ground-water sources. West Virginia had the lowest estimated irrigation of any state or territory of the United States, with only about 0.036 Mgal/d withdrawn from surface-water sources and 0.036 Mgal/d withdrawn from ground-water sources. Water withdrawal for commercial use was about 16.7 Mgal/d from surface-water sources and about 16.0 Mgal/d from ground-water sources. Water withdrawal for mining was about 9.78 Mgal/d from surface-water sources and about 4.89 Mgal/d from ground-water sources. The proportions of surface-water and ground-water withdrawals were similar in 1995 and 2004 (at about 3 percent ground water). Public-supply withdrawal for 2004 was about the same as for 2000 and 7 percent greater than the 1995 estimate. Domestic withdrawal for 2004 was about 18 percent less than the 1995 estimate. Withdrawal for thermoelectric power for 2004 was about 10 percent less than the 2000 estimate and about 18 percent greater than the 1995 estimate. Industrial withdrawal for 2004 was about 27 percent less than the estimate for 1995 and about the same as the estimate for 2000. Irrigation withdrawal for 2004 was about double that estimated for 2000. Commercial withdrawal for 2004 was down 28 percent from 1995. Mining withdrawals for 2004 were about 31 and 32 percent greater for surface and ground water, respectively, than estimates for 1995.

40 CFR 141.706 - Reporting source water monitoring results.

Code of Federal Regulations, 2013 CFR

2013-07-01

... results. 141.706 Section 141.706 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Cryptosporidium Source Water Monitoring Requirements § 141.706 Reporting source water monitoring results. (a) Systems must report results from the source water monitoring required under § 141.701 no later than 10...

40 CFR 141.706 - Reporting source water monitoring results.

Code of Federal Regulations, 2012 CFR

2012-07-01

... results. 141.706 Section 141.706 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Cryptosporidium Source Water Monitoring Requirements § 141.706 Reporting source water monitoring results. (a) Systems must report results from the source water monitoring required under § 141.701 no later than 10...

IDENTIFICATION OF SOURCES OF GROUND-WATER SALINIZA- TION USING GEOCHEMICAL TECHNIQUES

EPA Science Inventory

This report deals with salt-water sources that commonly mix and deteriorate fresh ground water. It reviews characteristics of salt-water sources and geochemical techniques that can be used to identify these sources after mixing has occurred. The report is designed to assist inves...

Effect of Safe Water on Arsenicosis: A Follow-up Study.

PubMed

Majumdar, Kunal K; Ghose, Aloke; Ghose, Nilima; Biswas, Anirban; Mazumder, D N Guha

2014-04-01

Arsenic pollution in groundwater, used for drinking purposes, has been envisaged as a problem of global concern. Treatment options for the management symptoms of chronic arsenicosis are limited. Mitigation option available for dealing with the health problem of ground water arsenic contamination rests mainly on supply of arsenic safe water in arsenic-endemic region of Indo-Bangladesh subcontinent. Limited information is available regarding the long-term effect of chronic arsenic toxicity after stoppage of consumption of arsenic-containing water. The current study was, therefore, done to assess, objectively, the effect of drinking arsenic safe water (<50 μg/L) on disease manifestation of arsenicosis. Manifestations of various skin lesions and systemic diseases associated with chronic arsenic exposure were ascertained initially by carrying on baseline study on 208 participants in Nadia (Cohort-I, with skin lesion and Cohort-II, without skin lesion) using a scoring system, as developed by us, and compared objectively at the end of each year for 3 year follow-up period. All the participants who had arsenic contaminated drinking water source in their houses were supplied with arsenic removal filters for getting arsenic-free water during the follow-up period. In participants belonging to Cohort-I, the skin score was found to improve significantly at the end of each year, and it was found to be reduced significantly from 2.17 ± 1.09 to 1.23 ± 1.17; P < 0.001 at the end of 3 year's intervention study indicating beneficial effect of safe water on skin lesions. The systemic disease symptom score was also found to improve, but less significantly, at the end of 3 years in both the cohorts. Most important observation during the follow-up study was persistence of severe symptoms of chronic lung disease and severe skin lesion including Bowen's disease in spite of taking arsenic-safe water. Further, death could not be prevented to occur because of lung cancer and severe lung disease. It is, therefore, an urgent need to make arrangement for availability of safe water source among the arsenic-affected people in the district. Many of the people in the affected villages are not aware of contamination of their home tube wells with arsenic. Awareness generation and motivation of the people for testing their drinking water sources for arsenic and environmental interventions like rain water harvesting, ground water recharge, and restricting excessive use of ground water for domestic and agricultural purposes are also important to prevent further exposure of arsenic to these people.

A GIS approach to conducting biogeochemical research in wetlands

NASA Technical Reports Server (NTRS)

Brannon, David P.; Irish, Gary J.

1985-01-01

A project was initiated to develop an environmental data base to address spatial aspects of both biogeochemical cycling and resource management in wetlands. Specific goals are to make regional methane flux estimates and site specific water level predictions based on man controlled water releases within a wetland study area. The project will contribute to the understanding of the Earth's biosphere through its examination of the spatial variability of methane emissions. Although wetlands are thought to be one of the primary sources for release of methane to the atmosphere, little is known about the spatial variability of methane flux. Only through a spatial analysis of methane flux rates and the environmental factors which influence such rates can reliable regional and global methane emissions be calculated. Data will be correlated and studied from Landsat 4 instruments, from a ground survey of water level recorders, precipitation recorders, evaporation pans, and supplemental gauges, and from flood gate water release; and regional methane flux estimates will be made.

Estimation of the Change in Freshwater Volume in the North Coast Limestone Upper Aquifer of Puerto Rico in the Rio Grande de Manati-Rio de la Plata Area between 1960 and 1990 and Implications on Public-Supply Water Availability

USGS Publications Warehouse

Gómez-Gómez, Fernando

2008-01-01

Ground water in the upper aquifer of the North Coast Limestone aquifer system historically has been the principal source of public-supply and self-supplied industrial water use in north-central Puerto Rico. Development of the aquifer for these two major water-use categories began in about 1930; however, withdrawals did not become an important water-supply source for sustaining local development until the 1960s. Ground-water withdrawals averaged about 6 million gallons per day from 1948 to the mid-1960s and peaked at about 33 million gallons per day in the 1980s. Withdrawals have since declined, averaging about 11.5 million gallons per day in 2002. Aquifer contamination by industrial chemical spills and by nitrates from agricultural and domestic sources initially reduced pumpage for public-supply use within localized areas, leading eventually to increased withdrawals at unaffected well fields. The long-term effect of unconstrained ground-water withdrawals has been a regional thinning of the freshwater lens in an area encompassing 50,600 acres between the Rio Grande de Manati and Rio de la Plata, generally north of latitude 18?25?. The effects of aquifer overdraft have been documented in the regional thinning of the freshwater lens, with an increase in dissolved-solids concentration in ground-water wells. Dissolved-solids concentration in public-supply wells were generally between 250 and 350 milligrams per liter during the 1960s, but increased to greater than 500 milligrams per liter in virtually all of the wells by 2000. Depletion of fresh ground water was estimated at 282,000 acre-feet: 103,000 acre-feet in the Rio Grande de Manati to Rio Cibuco area between 1960 and 1995, and 179,000 acre-feet in the Rio Cibuco to Rio de la Plata area between 1960 and 1992. Thus, aquifer freshwater volume depletion below mean sea level datum may have contributed as much as 38 percent (7.5 million gallons per day) of the 20-million gallons per day average withdrawal rate during the stated time periods. The calculated depletion of aquifer freshwater volume is equivalent to an average long-term rate of 8,400 acre-feet per year. Aquifer withdrawals can be anticipated to decline to about 10 million gallons per day by 2010 at the projected trend of well closures. The lost supply would have to be compensated from surface-water sources because the part of the North Coast Limestone aquifer system south of latitude 18?25?, although less vulnerable to saline-water encroachment, is not as productive.

The impact of submarine ground water discharge on a coastal ecosystem of the southern Baltic Sea: Results from the BONUS+ project AMBER

NASA Astrophysics Data System (ADS)

Vogler, Susann; Szymczycha, Beata; Gentz, Thorben; Dellwig, Olaf; Kotwiki, Lech; Endler, Rudolf; Pempkowiak, Janusz; Marcin Weslawski, Jan; Schlüter, Michael; Böttcher, Michael E.

2010-05-01

Besides direct surface water input of dissolved and particulate compounds (eg nutrients, metals) via rivers into coastal seas, submarine ground water discharge (SGD) is increasingly recognized to be an important factor. In spite of the recognition that many land-sea interfaces of the world are characterised by SGD, it is still unclear how important SGD via springs, seeps, or diffusive outflows is in terms of biogeochemical budgets for the Baltic Sea coastal regions. The main reason that this has not been caught up so far to a precision that is typical for other freshwater inputs is that direct discharge of groundwater into the coastal zone is often difficult to quantify. The influence of SGD is expected to be of particular socio-economic relevance as it influences eutrophication in near-coastal ecosystems and to be under pressure by anthropogenic activity and climate change. Therefore, the impact of near-shore submarine ground water discharge (SGD) on coastal ecosystems of the southern Baltic Sea is investigated as part of the AMBER project within the BONUS+ initiative. In AMBER, the quantitative importance of SGD on nutrient, metabolite, and trace metal budgets is investigated for parts of the Baltic Sea. Results will have implications to understand the role of SGD as a nutrient source and will provide data for further implementation into model environments for the prediction of scenarios of future environmental changes. Besides trace metals, nutrients, methane, DIC and metabolites species, a further focus forms the impact of SGD on biota. Stable isotopes (C-13, S-34, O-18) are planed to be used to identify sources, sinks, and abiotic and microbial conversions of dissolved and particulate compounds. Salinity and temperature profiles as well as Ra and Rn isotopes will help to identify and quantify SGD. Sediment structures potentially acting as aquifers are characterized by geochemical, sedimentological, and geophysical methods. During several sampling campaigns in 2009, seep-type SGD was investigated in the Puck Bay off the Polish coast. It is found that, as one of the potentially different ground water-derived sources, fresh ground waters escape from permeable sediments in form of localized seeps near the shore-line. The geochemical composition and vertical efflux rates of these ground waters are determined by usingpore water lances and seepage meters. Analyses revealed that the ground waters were sulfidic and the source for a number of elements in the water column including DIC and phosphate. Results will be discussed in terms of biogeochemical element transformations and consequences for the element fluxes into the water column.

A mobile and self-sufficient lab for high frequency measurements of stable water isotopes and chemistry of multiple water sources

NASA Astrophysics Data System (ADS)

Windhorst, David; Kraft, Philipp; Holly, Hartmut; Sahraei, Amir; Breuer, Lutz

2017-04-01

Technical advances over the last years have made instruments for stable water isotope and water chemistry measurements smaller, more durable and energy efficient. It is nowadays feasible to deploy such instruments in situ during field campaigns. Coupled to an automated sample delivery system, high temporal resolution online measurements of various sources are within the bounds of economic and technical possibility. However, the day to day operation of such equipment still requires either a lot of man power and infrastructure or the implementation of a quasi-self-sufficient system. The challenge remains on how to facilitate and remotely operate such a system. We present the design and implementation of the Water Analysis Trailer for Environmental Research (WATER), an autonomous platform consisting of instruments for stable water isotope and water chemistry analysis. The system takes and measures samples in high temporal resolution (<15 min) of up to 12 sources. To ensure an unmanned operation of up to one week several issues need to be addressed. The essential topics are: - self-sufficient power supply, - automated sample delivery and preparation, and - autonomous measurements and management interfacing all instruments. In addition to the basic requirements we implemented: - communication of all system states, alarm messages and measurement results to an internal as well as an external database via cellular telemetry, - automated storage of up to 300 frozen reference samples (100 mL, stored at -18°C), - climate control for temperature sensitive equipment (±1°C), - a local and remote (up to 20 km using radio telemetry) sensor network (i.e. to record states of the hydrological system and climate and soil conditions), also suitable to trigger specific measurements - automatic fire suppression and security system. The initial instrumentation includes a UV spectrometer (ProPs, Trios GmBH, Germany) to measure NO3-, COD, TOC and total suspended sediments, multiparameter water quality probe (YSI600R, YSI, USA) to measure electrical conductivity and pH, and a stable water isotope analyzer (L2130-i, Picarro, USA) coupled to a continuous water sampler (A0217, Picarro, USA). Fourty soil moisture, temperature and electrical conductivity sensors (5TE, Decagon, USA) are connect to the remote sensor network (A850, Adcon, Austria) and rain gauges and a climate station (WXT520, Vaisala, Finland) are connected to the local sensor network via SDI-12. In a first field trial starting in March 2017 the mobile laboratory will be used to study the hydrological processes in the developed landscape of the Schwingbach catchment (Germany). We are confident, that the unprecedented degree in detail, the measurements promise, will further accelerate our hydrological understanding and the interaction of various discharge generating sources.

Modeling water demand when households have multiple sources of water

NASA Astrophysics Data System (ADS)

Coulibaly, Lassina; Jakus, Paul M.; Keith, John E.

2014-07-01

A significant portion of the world's population lives in areas where public water delivery systems are unreliable and/or deliver poor quality water. In response, people have developed important alternatives to publicly supplied water. To date, most water demand research has been based on single-equation models for a single source of water, with very few studies that have examined water demand from two sources of water (where all nonpublic system water sources have been aggregated into a single demand). This modeling approach leads to two outcomes. First, the demand models do not capture the full range of alternatives, so the true economic relationship among the alternatives is obscured. Second, and more seriously, economic theory predicts that demand for a good becomes more price-elastic as the number of close substitutes increases. If researchers artificially limit the number of alternatives studied to something less than the true number, the price elasticity estimate may be biased downward. This paper examines water demand in a region with near universal access to piped water, but where system reliability and quality is such that many alternative sources of water exist. In extending the demand analysis to four sources of water, we are able to (i) demonstrate why households choose the water sources they do, (ii) provide a richer description of the demand relationships among sources, and (iii) calculate own-price elasticity estimates that are more elastic than those generally found in the literature.

40 CFR 141.701 - Source water monitoring.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Source water monitoring. 141.701 Section 141.701 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Treatment for Cryptosporidium Source Water...

40 CFR 141.701 - Source water monitoring.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Source water monitoring. 141.701 Section 141.701 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Treatment for Cryptosporidium Source Water...

40 CFR 141.701 - Source water monitoring.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Source water monitoring. 141.701 Section 141.701 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Treatment for Cryptosporidium Source Water...

40 CFR 141.701 - Source water monitoring.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Source water monitoring. 141.701 Section 141.701 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Treatment for Cryptosporidium Source Water...

40 CFR 141.701 - Source water monitoring.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Source water monitoring. 141.701 Section 141.701 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Treatment for Cryptosporidium Source Water...

WATER QUALITY IN SOURCE WATER, TREATMENT, AND DISTRIBUTION SYSTEMS

EPA Science Inventory

Most drinking water utilities practice the multiple-barrier concept as the guiding principle for providing safe water. This chapter discusses multiple barriers as they relate to the basic criteria for selecting and protecting source waters, including known and potential sources ...

The risk assessment of sudden water pollution for river network system under multi-source random emission

NASA Astrophysics Data System (ADS)

Li, D.

2016-12-01

Sudden water pollution accidents are unavoidable risk events that we must learn to co-exist with. In China's Taihu River Basin, the river flow conditions are complicated with frequently artificial interference. Sudden water pollution accident occurs mainly in the form of a large number of abnormal discharge of wastewater, and has the characteristics with the sudden occurrence, the uncontrollable scope, the uncertainty object and the concentrated distribution of many risk sources. Effective prevention of pollution accidents that may occur is of great significance for the water quality safety management. Bayesian networks can be applied to represent the relationship between pollution sources and river water quality intuitively. Using the time sequential Monte Carlo algorithm, the pollution sources state switching model, water quality model for river network and Bayesian reasoning is integrated together, and the sudden water pollution risk assessment model for river network is developed to quantify the water quality risk under the collective influence of multiple pollution sources. Based on the isotope water transport mechanism, a dynamic tracing model of multiple pollution sources is established, which can describe the relationship between the excessive risk of the system and the multiple risk sources. Finally, the diagnostic reasoning algorithm based on Bayesian network is coupled with the multi-source tracing model, which can identify the contribution of each risk source to the system risk under the complex flow conditions. Taking Taihu Lake water system as the research object, the model is applied to obtain the reasonable results under the three typical years. Studies have shown that the water quality risk at critical sections are influenced by the pollution risk source, the boundary water quality, the hydrological conditions and self -purification capacity, and the multiple pollution sources have obvious effect on water quality risk of the receiving water body. The water quality risk assessment approach developed in this study offers a effective tool for systematically quantifying the random uncertainty in plain river network system, and it also provides the technical support for the decision-making of controlling the sudden water pollution through identification of critical pollution sources.

The Sparta aquifer in Arkansas' critical ground-water areas: Response of the aquifer to supplying future water needs

USGS Publications Warehouse

Hays, Phillip D.; Fugitt, D. Todd

1999-01-01

The Sparta aquifer is a confined aquifer of great regional importance that comprises a sequence of unconsolidated sand, silt, and clay units extending across much of eastern and southeastern Arkansas and into adjoining States. Water use from the aquifer has doubled since 1975 and continues to increase, and large water-level declines are occurring in many areas of the aquifer. To focus State attention and resources on the growing problem and to provide a mechanism for locally based education and management, the Arkansas Soil and Water Conservation Commission has designated Critical Ground-Water Areas in some counties (see page 6, ?What is a Critical Ground-Water Area??). Ground-water modeling study results show that the aquifer cannot continue to meet growing water-use demands. Dewatering of the primary producing sands is predicted to occur within 10 years in some areas if current trends continue. The predicted dewatering will cause reduced yields and damage the aquifer. Modeling also shows that a concerted ground-water conservation management plan could enable sustainable use of the aquifer. Water-conservation measures and use of alternative sources that water managers in Union County (an area of high demand and growth in Arkansas' initial five-county Critical Ground-Water Area) think to be realistic options result in considerable recovery in water levels in the aquifer during a 30-year model simulation.

[Effect of antecedent dry period on water quality of urban storm runoff pollution].

PubMed

Bian, Bo

2009-12-01

Identified the main factor influencing urban rainfall-runoff pollution provides a scientific basis for urban rainfall-runoff pollution control and management. Therefore, starting in May 2006, a study was conducted to characterize water quality from representative land uses types in Zhenjiang to analyse the effect of antecedent dry period on stormwater runoff quality. The results show that the beginning of rainfall, with the increase of antecedent dry periods, the percentages of less than 40 microm is increased, the correlation of the water quality parameters (TN, TP, Zn, Pb, Cu, TSS and COD) and antecedent dry period shows a significant positive correlation, dissolved pollutants in the initial period surface runoff is increased. These findings show that facilitating the recognition of antecedent dry periods is the main factor influencing the change in concentration and partitioning of pollutants to provide the scientific basis for non-point source pollution control and management.

Removal of microcystin-LR from spiked water using either activated carbon or anthracite as filter material.

PubMed

Drogui, Patrick; Daghrir, Rimeh; Simard, Marie-Christine; Sauvageau, Christine; Blais, Jean François

2012-01-01

The occurrence of cyanobacterial toxins (blue-green algae) in drinking water sources is a big concern for human health. Removal of microcystin-LR (MC-LR) from drinking water was evaluated at the laboratory pilot scale using either granular activated carbon (GAC) or powdered activated carbon (PAC) and compared with the treatment using anthracite as filter material. Virgin GAC was more effective at removing MC-LR (initial concentration ranging from 9 to 47 microg L(-1)) to reach the World Health Organization recommended level (1.0 microg L(-1)). When the GAC filter was colonized by bacteria, the filter became less effective at removing MC-LR owing to competitive reactions occurring between protein adsorption (released by bacteria) and MC-LR adsorption. Using PAC, the concentration of MC-LR decreased from 22 to 3 microg L(-1) (removal of 86% of MC-LR) by the addition of 100 mg PAC L(-1).

Application of factor analysis to the water quality in reservoirs

NASA Astrophysics Data System (ADS)

Silva, Eliana Costa e.; Lopes, Isabel Cristina; Correia, Aldina; Gonçalves, A. Manuela

2017-06-01

In this work we present a Factor Analysis of chemical and environmental variables of the water column and hydro-morphological features of several Portuguese reservoirs. The objective is to reduce the initial number of variables, keeping their common characteristics. Using the Factor Analysis, the environmental variables measured in the epilimnion and in the hypolimnion, together with the hydromorphological characteristics of the dams were reduced from 63 variables to only 13 factors, which explained a total of 83.348% of the variance in the original data. After performing rotation using the Varimax method, the relations between the factors and the original variables got clearer and more explainable, which provided a Factor Analysis model for these environmental variables using 13 varifactors: Water quality and distance to the source, Hypolimnion chemical composition, Sulfite-reducing bacteria and nutrients, Coliforms and faecal streptococci, Reservoir depth, Temperature, Location, among other factors.

Application of ozone to eliminate tertiary treatment of wastewater used for industrial cooling

NASA Astrophysics Data System (ADS)

Merrill, D. T.; Parker, D. S.

1982-02-01

The beneficial performance of ozone (biofouling, corrosion, and chemical scaling control), when used as the sole source of cooling water treatment for air conditioning systems, could be obtained at higher cooling water temperatures typical of industrial cooling with secondary municipal effluent (SME) used as the cooling medium was investigated. A pilot cooling system was constructed and a 6 month experimental study initiated to determine process limits, mechanisms of scaling inhibition by ozone, and to evaluate factors influencing technical/economic feasibility. It was found that, while ozone use adequately controlled corrosion and biofouling, chemical scaling could not be prevented at conditions necessary for significant economic justification. Calculations indicate that the makeup waters (SME) used will become saturated with respect to calcium phosphate at less than 2 cycles of concentration, hence, a scaling potential exists at conditions less stringent than those used in the present study.

Seasonal Shifts in Primary Water Source Type: A Comparison of Largely Pastoral Communities in Uganda and Tanzania

PubMed Central

Pearson, Amber L.; Zwickle, Adam; Namanya, Judith; Rzotkiewicz, Amanda; Mwita, Emiliana

2016-01-01

Many water-related illnesses show an increase during the wet season. This is often due to fecal contamination from runoff, yet, it is unknown whether seasonal changes in water availability may also play a role in increased illness via changes in the type of primary water source used by households. Very little is known about the dynamic aspects of access to water and changes in source type across seasons, particularly in semi-arid regions with annual water scarcity. The research questions in this study were: (1) To what degree do households in Uganda (UG) and Tanzania (TZ) change primary water source type between wet and dry seasons?; and (2) How might seasonal changes relate to water quality and health? Using spatial survey data from 92 households each in UG and TZ this study found that, from wet to dry season, 26% (UG) and 9% (TZ) of households switched from a source with higher risk of contamination to a source with lower risk. By comparison, only 20% (UG) and 0% (TZ) of households switched from a source with lower risk of contamination to a source with higher risk of contamination. This research suggests that one pathway through which water-related disease prevalence may differ across seasons is the use of water sources with higher risk contamination, and that households with access to sources with lower risks of contamination sometimes choose to use more contaminated sources. PMID:26828507

Occurrence, Source, and Human Infection Potential of Cryptosporidium and Giardia spp. in Source and Tap Water in Shanghai, China▿

PubMed Central

Feng, Yaoyu; Zhao, Xukun; Chen, Jiaxu; Jin, Wei; Zhou, Xiaonong; Li, Na; Wang, Lin; Xiao, Lihua

2011-01-01

Genotyping studies on the source and human infection potential of Cryptosporidium oocysts in water have been almost exclusively conducted in industrialized nations. In this study, 50 source water samples and 30 tap water samples were collected in Shanghai, China, and analyzed by the U.S. Environmental Protection Agency (EPA) Method 1623. To find a cost-effective method to replace the filtration procedure, the water samples were also concentrated by calcium carbonate flocculation (CCF). Of the 50 source water samples, 32% were positive for Cryptosporidium and 18% for Giardia by Method 1623, whereas 22% were positive for Cryptosporidium and 10% for Giardia by microscopy of CCF concentrates. When CCF was combined with PCR for detection, the occurrence of Cryptosporidium (28%) was similar to that obtained by Method 1623. Genotyping of Cryptosporidium in 17 water samples identified the presence of C. andersoni in 14 water samples, C. suis in 7 water samples, C. baileyi in 2 water samples, C. meleagridis in 1 water sample, and C. hominis in 1 water sample. Therefore, farm animals, especially cattle and pigs, were the major sources of water contamination in Shanghai source water, and most oocysts found in source water in the area were not infectious to humans. Cryptosporidium oocysts were found in 2 of 30 tap water samples. The combined use of CCF for concentration and PCR for detection and genotyping provides a less expensive alternative to filtration and fluorescence microscopy for accurate assessment of Cryptosporidium contamination in water, although the results from this method are semiquantitative. PMID:21498768

Microbial pathogens in source and treated waters from drinking water treatment plants in the United States and implications for human health.

PubMed

King, Dawn N; Donohue, Maura J; Vesper, Stephen J; Villegas, Eric N; Ware, Michael W; Vogel, Megan E; Furlong, Edward F; Kolpin, Dana W; Glassmeyer, Susan T; Pfaller, Stacy

2016-08-15

An occurrence survey was conducted on selected pathogens in source and treated drinking water collected from 25 drinking water treatment plants (DWTPs) in the United States. Water samples were analyzed for the protozoa Giardia and Cryptosporidium (EPA Method 1623); the fungi Aspergillus fumigatus, Aspergillus niger and Aspergillus terreus (quantitative PCR [qPCR]); and the bacteria Legionella pneumophila (qPCR), Mycobacterium avium, M. avium subspecies paratuberculosis, and Mycobacterium intracellulare (qPCR and culture). Cryptosporidium and Giardia were detected in 25% and in 46% of the source water samples, respectively (treated waters were not tested). Aspergillus fumigatus was the most commonly detected fungus in source waters (48%) but none of the three fungi were detected in treated water. Legionella pneumophila was detected in 25% of the source water samples but in only 4% of treated water samples. M. avium and M. intracellulare were both detected in 25% of source water, while all three mycobacteria were detected in 36% of treated water samples. Five species of mycobacteria, Mycobacterium mucogenicum, Mycobacterium phocaicum, Mycobacterium triplex, Mycobacterium fortuitum, and Mycobacterium lentiflavum were cultured from treated water samples. Although these DWTPs represent a fraction of those in the U.S., the results suggest that many of these pathogens are widespread in source waters but that treatment is generally effective in reducing them to below detection limits. The one exception is the mycobacteria, which were commonly detected in treated water, even when not detected in source waters. Published by Elsevier B.V.

Potential of Nanotechnology based water treatment solutions for the improvement of drinking water supplies in developing countries

NASA Astrophysics Data System (ADS)

Dutta, Joydeep; Bhattacharya, Prosun; Bundschuh, Jochen

2016-04-01

Over the last decades explosive population growth in the world has led to water scarcity across the globe putting additional pressure already scarce ground water resources and is pushing scientists and researchers to come up with new alternatives to monitor and treat water for use by mankind and for food security. Nearly 4 billion people around the world are known to lack access to clean water supply. Systematic water quality data is important for the assessment of health risks as well as for developing appropriate and affordable technologies for waste and drinking water treatments, and long-term decision making policy against water quality management. Traditional water treatment technologies are generally chemical-intensive processes requiring extremely large infrastructural support thus limiting their effective applications in developing nations which creates an artificial barrier to the application of technological solutions for the provision of clean water. Nanotechnology-based systems are in retrospect, smaller, energy and resource efficient. Economic impact assessment of the implementation of nanotechnology in water treatment and studies on cost-effectiveness and environmental and social impacts is of key importance prior to its wide spread acceptance. Government agencies and inter-governmental bodies driving research and development activities need to measure the effective potential of nanotechnology as a solution to global water challenges in order to effectively engage in fiscal, economic and social issues at national and international levels for different types of source waters with new national and international initiatives on nanotechnology and water need to be launched. Environmental pollution and industrialization in global scale is further leading to pollution of available water sources and thus hygienically friendly purification technologies are the need of the hour. Thus cost-effective treatment of pollutants for the transformation of hazardous substances into benign forms that can potentially be addressed through Nanotechnology based filters utilizing photocatalytic or electrocatalytic systems could be further explored. Development of these techniques together with other superadsorbants would make it possible to install delocalized systems with very little capital investment and operation and maintenance costs suitable for installation in less developed countries.

Warming combined with more extreme precipitation regimes modifies the water sources used by trees.

PubMed

Grossiord, Charlotte; Sevanto, Sanna; Dawson, Todd E; Adams, Henry D; Collins, Adam D; Dickman, Lee T; Newman, Brent D; Stockton, Elizabeth A; McDowell, Nate G

2017-01-01

The persistence of vegetation under climate change will depend on a plant's capacity to exploit water resources. We analyzed water source dynamics in piñon pine and juniper trees subjected to precipitation reduction, atmospheric warming, and to both simultaneously. Piñon and juniper exhibited different and opposite shifts in water uptake depth in response to experimental stress and background climate over 3 yr. During a dry summer, juniper responded to warming with a shift to shallow water sources, whereas piñon pine responded to precipitation reduction with a shift to deeper sources in autumn. In normal and wet summers, both species responded to precipitation reduction, but juniper increased deep water uptake and piñon increased shallow water uptake. Shifts in the utilization of water sources were associated with reduced stomatal conductance and photosynthesis, suggesting that belowground compensation in response to warming and water reduction did not alleviate stress impacts for gas exchange. We have demonstrated that predicted climate change could modify water sources of trees. Warming impairs juniper uptake of deep sources during extended dry periods. Precipitation reduction alters the uptake of shallow sources following extended droughts for piñon. Shifts in water sources may not compensate for climate change impacts on tree physiology. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

The potential use of rainwater as alternative source of drinking water by using laterite soil as natural adsorbent

NASA Astrophysics Data System (ADS)

Omar, Khairunnisa Fakhriah Mohd; Palaniandy, Puganeshwary; Adlan, Mohd Nordin; Aziz, Hamidi Abdul; Subramaniam, Ambarasi

2017-10-01

Generally, the rainwater has low concentration of pollutants, whereby it is applicable for domestic water supply. Due to the low concentration of pollutants, further treatment such as adsorption is necessary to treat the harvested rainwater as an alternative source of drinking water supply. Therefore, this research has been carried out to determine the quality of rainwater from different types of locations, which are; rural residential area, urban residential area, agricultural area, industrial area, and open surface. The rainwater sampling was carried out from September 2014 to December 2015. The parameters that have been analysed during the sampling process are chemical oxygen demand (COD), turbidity, heavy metals, and Escherichia coli (E.coli). The sampling results show that the rainwater provides low concentration of contaminants. Thus, it has high potential to be used as alternative source of potable and non potable water supply with a suitable treatment. Due to that, an experimental work contained of 86 of designated experiments for a batch study has been carried out to determine the performance of laterite soil as an adsorbent to remove pollutants that present in the rainwater (i.e. zinc, manganese, and E.coli). The operating factors involved in the experimental works are pH, mass of adsorbents, contact time, initial concentration of zinc, manganese, and E.coli. In this study, the experimental data of the batch study was analysed by developing regression model equation and analysis of variance. Perturbation plots were analysed to determine the effectiveness of the operating factors by developing response surface model, resulting that the high removals of zinc, manganese, and E.coli are 95.8%, 94.05% and 100%, respectively. Overall, this research works found out that the rainwater has a good quality as alternative source of drinking water by providing a suitable treatment. The application of laterite soil as natural adsorbent shows that it has potential to be used as the response surface model provide a good removal for zinc, manganese, and E.coli.

A Strategy for Federal Science and Technology to Support Water Availability and Quality in the United States

DTIC Science & Technology

2007-09-01

Subcommittee on Water Availability and Quality Microbial source tracking to identify the source of fecal contamination Many of the Nation’s resource...water- quality health standards. In addition, identi- fication of fecal sources is relevant to source-water protection programs and to the development...estuaries, snowpack, and soil . • Develop sensors and systems to measure water quality inexpensively in real time. Develop innovative water-use technologies

10 CFR 70.39 - Specific licenses for the manufacture or initial transfer of calibration or reference sources.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Specific licenses for the manufacture or initial transfer... manufacture or initial transfer of calibration or reference sources. (a) An application for a specific license to manufacture or initially transfer calibration or reference sources containing plutonium, for...

Sources and Contributions of Oxygen During Microbial Pyrite Oxidation: the Triple Oxygen Isotopes of Sulfate

NASA Astrophysics Data System (ADS)

Ziegler, K.; Coleman, M. L.; Mielke, R. E.; Young, E. D.

2008-12-01

The triple isotopes of oxygen (Δ17O' = δ17O'-0.528 × δ18O' using logarithmic deltas) can trace the oxygen sources of sulfate produced during sulfide oxidation, an important biogeochemical process on Earth's surface and possibly also on Mars [1]. δ18OSO4 compositions are determined by the isotopic selectivity of the mechanism(s) responsible for their changes, and the δ18O value of the reactants (O2 vs. H2O). The relative proportional importance and contribution of each of those sources and mechanisms, as well as their associated isotopic fractionations, are not well understood. We are investigating the use of Δ 17O as a quantitative and qualitative tracer for the different processes and oxygen sources involved in sulfate production. Δ17O signatures are distinct fingerprints of these reservoirs, independent of fractionation factors that can be ambiguous. We conducted controlled abiotic and biotic (Acidithiobacillus ferrooxidans, A.f.) laboratory experiments in which water was spiked with 18O, allowing us to quantify the sources of sulfate oxygen and therefore the processes attending sulfate formation. Results of this Δ17O tracer study show that A.f. microbes initiate pyrite S-oxidation within hours of exposure, and that sulfate is produced from ~90% atmospheric oxygen. This initial lag-phase (< 3 days) is characterized by subtle and multiple changes in oxygen source and contribution that is likely due to the adjustment of the microbial metabolism from S to Fe2+-oxidation. A more detailed understanding of the microbial mechanisms and behavior in the initial lag-phase will aid in the understanding of the ecological conditions required for microbial populations to establish and survive. An exponential phase of growth, facilitated by microbial Fe2+-oxidation, follows. The source of sulfate rapidly switches to abiotic sulfide oxidation during exponential growth and the source of oxygen switches from atmospheric O2 to nearly ~100% water. Pending acquisition of complimentary chemistry data (in progress), we interpret our isotope data to indicate that the biotic fractionation factor ɛ18OSO4-O2 of at least ~ -25 to - 35‰ is augmented by microbially induced kinetic fractionation; it is larger than expected based on published equilibrium values [2,3,4]. Our inferred ɛ18OSO4-H2O of at least ~+10‰ is similar to some reported values. These new insights into the close links between microbial life cycle and sources of sulfate oxygen during sulfide oxidation, and their oxygen isotopic expressions, will help elucidate the role of microbial oxidation in natural systems. If microbial populations in natural systems remain in a perpetual lag-phase due to constrains of chemistry, atmospheric oxygen will imprint its isotopic signature onto sulfate deposits. Ultimately, such data could be used as biosignatures on Early Earth or Mars. [1] Brunner and Coleman (2008) EPSL 270, 63-72. [2] Balci et al. (2007) GCA 71, 3796-3811. [3] Pisapia et al. (2007) GCA 71, 2474-2490. [4] Taylor et al. (1984) GCA 48, 2669-2678.

A National survey of methyl tert-butyl ether and other volatile organic compounds in drinking-water sources: Results of the random source-water survey

USGS Publications Warehouse

Grady, Stephen J.

2002-01-01

Methyl tert-butyl ether (MTBE) was detected in source water used by 8.7 percent of randomly selected community water systems (CWSs) in the United States at concentrations that ranged from 0.2 to 20 micrograms per liter (μg/L). The Random Survey conducted by the U.S. Geological Survey, in cooperation with the Metropolitan Water District of Southern California and the Oregon Health & Science University, was designed to provide an assessment of the frequency of detection, concentration, and distribution of MTBE, three other ether gasoline oxygenates, and 62 other volatile organic compounds (VOCs) in ground- and surface-water sources used for drinking-water supplies. The Random Survey was the first of two components of a national assessment of the quality of source water supplying CWSs sponsored by the American Water Works Association Research Foundation. A total of 954 CWSs were selected for VOC sampling from the population of nearly 47,000 active, self-supplied CWSs in all 50 States, Native American Lands, and Puerto Rico based on a statistical design that stratified on CWS size (population served), type of source water (ground and surface water), and geographic distribution (State).At a reporting level of 0.2 μg/L, VOCs were detected in 27 percent of source-water samples collected from May 3, 1999 through October 23, 2000. Chloroform (in 13 percent of samples) was the most frequently detected of 42 VOCs present in the source-water samples, followed by MTBE. VOC concentrations were generally less than 10 μg/L 95 percent of the 530 detections and 63 percent were less than 1.0 μg/L. Concentrations of 1,1-dichloroethene, tetrachloroethene, trichloroethene, vinyl chloride, and total trihalomethanes (TTHMs), however, exceeded drinking-water regulations in eight samples.Detections of most VOCs were more frequent in surface-water sources than in ground-water sources, with gasoline compounds collectively and MTBE individually detected significantly more often in surface water. Use of personal and commercial motorized watercraft on surface-water bodies that are drinking-water sources is probably the reason for the elevated detections of gasoline contaminants relative to ground water. MTBE detections demonstrated a seasonal pattern with more frequent detections in surface water in summer months, which is consistent with seasonal watercraft use.The detection frequency of most VOCs was significantly related to urban land use and population density. Detections of any VOC, non-trihalo-methane compounds, gasoline compounds collectively, the specific gasoline compounds benzene, toluene, ethylbenzene, and xylenes (BTEX), MTBE, solvents, and refrigerants were significantly greater in areas with more than 60 percent urban land use and (or) population density greater than 1,000 people per square mile than in source waters from less urbanized or lower population-density areas. MTBE detections were five times more frequent in source waters from areas with high MTBE use than in source waters from low or no MTBE use, but, unlike other gasoline compounds, MTBE detections were not significantly related to the density of gasoline storage tanks near drinking-water sources.

Trends and seasonality of river nutrients in agricultural catchments: 18years of weekly citizen science in France.

PubMed

Abbott, Benjamin W; Moatar, Florentina; Gauthier, Olivier; Fovet, Ophélie; Antoine, Virginie; Ragueneau, Olivier

2018-05-15

Agriculture and urbanization have disturbed three-quarters of global ice-free land surface, delivering huge amounts of nitrogen and phosphorus to freshwater ecosystems. These excess nutrients degrade habitat and threaten human food and water security at a global scale. Because most catchments are either currently subjected to, or recovering from anthropogenic nutrient loading, understanding the short- and long-term responses of river nutrients to changes in land use is essential for effective management. We analyzed a never-published, 18-year time series of anthropogenic (NO 3 - and PO 4 3- ) and naturally derived (dissolved silica) riverine nutrients in 13 catchments recovering from agricultural pollution in western France. In a citizen science initiative, high-school students sampled catchments weekly, which ranged from 26 to 1489km 2 . Nutrient concentrations decreased substantially over the period of record (19 to 50% for NO 3 - and 14 to 80% for PO 4 3- ), attributable to regional, national, and international investment and regulation, which started immediately prior to monitoring. For the majority of catchments, water quality during the summer low-flow period improved faster than during winter high-flow conditions, and annual minimum concentrations improved relatively faster than annual maximum concentrations. These patterns suggest that water-quality improvements were primarily due to elimination of discrete nutrient sources with seasonally-constant discharge (e.g. human and livestock wastewater), agreeing with available land-use and municipal records. Surprisingly, long-term nutrient decreases were not accompanied by changes in nutrient seasonality in most catchments, attributable to persistent, diffuse nutrient stocks. Despite decreases, nutrient concentrations in almost all catchments remained well above eutrophication thresholds, and because additional improvements will depend on decreasing diffuse nutrient sources, future gains may be much slower than initial rate of recovery. These findings demonstrate the value of citizen science initiatives in quantifying long-term and seasonal consequences of changes in land management, which are necessary to identify sustainable limits and predict recovery timeframes. Copyright © 2017 Elsevier B.V. All rights reserved.

The geochemistry of water near a surficial organic-rich uranium deposit, northeastern Washington State, U.S.A.

USGS Publications Warehouse

Zielinski, R.A.; Otton, J.K.; Wanty, R.B.; Pierson, C.T.

1987-01-01

The chemistry of three stream, three spring and six near-surface waters in the vicinity of a Holocene organic-rich uranium deposit is described, with particular emphasis on the chemistry of U. Results characterize the solution behavior of uranium as U-bearing water interacts with relatively undecomposed, surficial organic matter. Of the measured major and trace chemical species, only U is consistently highly enriched (17-318 ppb) relative to reported values for regional waters, or to literature values for waters in largely granitic terrains. R-mode factor analysis of the chemical data suggests that most U is present in a soluble form, but that some U is also associated with fine suspended particulates of clay, organic matter, or hydrous oxides. Calculations that apply thermodynamic data to predict U speciation in solution indicate the relative importance of uranyl carbonate and uranyl phosphate complexes. Analysis of more finely filtered samples (0.05 ??m vs. 0.45 ??m), and direct radiographic observations using fission-track detectors suspended in the waters indicate the presence of some uraniferous particulate matter. Application of existing thermodynamic data for uranous- and uranyl-bearing minerals indicates that all waters are undersaturated with U minerals as long as ambient Eh ??? +0.1 v. If coexisting surface and near-surface waters are sufficiently oxidizing, initial fixation of U in the deposit should be by a mechanism of adsorption. Alternatively, more reducing conditions may prevail in deeper pore waters of the organic-rich host sediments, perhaps leading to direct precipitation or diagenetic formation of U4+ minerals. A 234U 238U alpha activity ratio of 1.08 ?? 0.02 in a spring issuing from a hillslope above the deposit suggests a relatively soluble source of U. In contrast, higher activity ratios of 234U 238U (??? 1.3) in waters in contact with the uraniferous valley-fill sediments suggest differences in the nature of interaction between groundwater and the local, U-rich source rocks. ?? 1987.

Microbial risk assessment of drinking water based on hydrodynamic modelling of pathogen concentrations in source water.

PubMed

Sokolova, Ekaterina; Petterson, Susan R; Dienus, Olaf; Nyström, Fredrik; Lindgren, Per-Eric; Pettersson, Thomas J R

2015-09-01

Norovirus contamination of drinking water sources is an important cause of waterborne disease outbreaks. Knowledge on pathogen concentrations in source water is needed to assess the ability of a drinking water treatment plant (DWTP) to provide safe drinking water. However, pathogen enumeration in source water samples is often not sufficient to describe the source water quality. In this study, the norovirus concentrations were characterised at the contamination source, i.e. in sewage discharges. Then, the transport of norovirus within the water source (the river Göta älv in Sweden) under different loading conditions was simulated using a hydrodynamic model. Based on the estimated concentrations in source water, the required reduction of norovirus at the DWTP was calculated using quantitative microbial risk assessment (QMRA). The required reduction was compared with the estimated treatment performance at the DWTP. The average estimated concentration in source water varied between 4.8×10(2) and 7.5×10(3) genome equivalents L(-1); and the average required reduction by treatment was between 7.6 and 8.8 Log10. The treatment performance at the DWTP was estimated to be adequate to deal with all tested loading conditions, but was heavily dependent on chlorine disinfection, with the risk of poor reduction by conventional treatment and slow sand filtration. To our knowledge, this is the first article to employ discharge-based QMRA, combined with hydrodynamic modelling, in the context of drinking water. Copyright © 2015 Elsevier B.V. All rights reserved.

Drivers of microbiological quality of household drinking water - a case study in rural Ethiopia.

PubMed

Usman, Muhammed A; Gerber, Nicolas; Pangaribowo, Evita H

2018-04-01

This study aims at assessing the determinants of microbiological contamination of household drinking water under multiple-use water systems in rural areas of Ethiopia. For this analysis, a random sample of 454 households was surveyed between February and March 2014, and water samples from community sources and household storage containers were collected and tested for fecal contamination. The number of Escherichia coli (E. coli) colony-forming units per 100 mL water was used as an indicator of fecal contamination. The microbiological tests demonstrated that 58% of household stored water samples and 38% of protected community water sources were contaminated with E. coli. Moreover, most improved water sources often considered to provide safe water showed the presence of E. coli. The result shows that households' stored water collected from unprotected wells/springs had higher levels of E. coli than stored water from alternative sources. Distance to water sources and water collection containers are also strongly associated with stored water quality. To ensure the quality of stored water, the study suggests that there is a need to promote water safety from the point-of-source to point-of-use, with due considerations for the linkages between water and agriculture to advance the Sustainable Development Goal 6 of ensuring access to clean water for everyone.

Groundwater-quality data in seven GAMA study units: results from initial sampling, 2004-2005, and resampling, 2007-2008, of wells: California GAMA Program Priority Basin Project

USGS Publications Warehouse

Kent, Robert; Belitz, Kenneth; Fram, Miranda S.

2014-01-01

The Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) Program was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The GAMA-PBP began sampling, primarily public supply wells in May 2004. By the end of February 2006, seven (of what would eventually be 35) study units had been sampled over a wide area of the State. Selected wells in these first seven study units were resampled for water quality from August 2007 to November 2008 as part of an assessment of temporal trends in water quality by the GAMA-PBP. The initial sampling was designed to provide a spatially unbiased assessment of the quality of raw groundwater used for public water supplies within the seven study units. In the 7 study units, 462 wells were selected by using a spatially distributed, randomized grid-based method to provide statistical representation of the study area. Wells selected this way are referred to as grid wells or status wells. Approximately 3 years after the initial sampling, 55 of these previously sampled status wells (approximately 10 percent in each study unit) were randomly selected for resampling. The seven resampled study units, the total number of status wells sampled for each study unit, and the number of these wells resampled for trends are as follows, in chronological order of sampling: San Diego Drainages (53 status wells, 7 trend wells), North San Francisco Bay (84, 10), Northern San Joaquin Basin (51, 5), Southern Sacramento Valley (67, 7), San Fernando–San Gabriel (35, 6), Monterey Bay and Salinas Valley Basins (91, 11), and Southeast San Joaquin Valley (83, 9). The groundwater samples were analyzed for a large number of synthetic organic constituents (volatile organic compounds [VOCs], pesticides, and pesticide degradates), constituents of special interest (perchlorate, N-nitrosodimethylamine [NDMA], and 1,2,3-trichloropropane [1,2,3-TCP]), and naturally-occurring inorganic constituents (nutrients, major and minor ions, and trace elements). Naturally-occurring isotopes (tritium, carbon-14, and stable isotopes of hydrogen and oxygen in water) also were measured to help identify processes affecting groundwater quality and the sources and ages of the sampled groundwater. Nearly 300 constituents and water-quality indicators were investigated. Quality-control samples (blanks, replicates, and samples for matrix spikes) were collected at 24 percent of the 55 status wells resampled for trends, and the results for these samples were used to evaluate the quality of the data for the groundwater samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that contamination was not a noticeable source of bias in the data for the groundwater samples. Differences between replicate samples were mostly within acceptable ranges, indicating acceptably low variability in analytical results. Matrix-spike recoveries were within the acceptable range (70 to 130 percent) for 75 percent of the compounds for which matrix spikes were collected. This study did not attempt to evaluate the quality of water delivered to consumers. After withdrawal, groundwater typically is treated, disinfected, and blended with other waters to maintain acceptable water quality. The benchmarks used in this report apply to treated water that is served to the consumer, not to untreated groundwater. To provide some context for the results, however, concentrations of constituents measured in these groundwater samples were compared with benchmarks established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CDPH). Comparisons between data collected for this study and benchmarks for drinking water are for illustrative purposes only and are not indicative of compliance or non-compliance with those benchmarks. Most constituents that were detected in groundwater samples from the trend wells were found at concentrations less than drinking-water benchmarks. Four VOCs—trichloroethene, tetrachloroethene, 1,2-dibromo-3-chloropropane, and methyl tert-butyl ether—were detected in one or more wells at concentrations greater than their health-based benchmarks, and six VOCs were detected in at least 10 percent of the samples during initial sampling or resampling of the trend wells. No pesticides were detected at concentrations near or greater than their health-based benchmarks. Three pesticide constituents—atrazine, deethylatrazine, and simazine—were detected in more than 10 percent of the trend-well samples during both sampling periods. Perchlorate, a constituent of special interest, was detected more frequently, and at greater concentrations during resampling than during initial sampling, but this may be due to a change in analytical method between the sampling periods, rather than to a change in groundwater quality. Another constituent of special interest, 1,2,3-TCP, was also detected more frequently during resampling than during initial sampling, but this pattern also may not reflect a change in groundwater quality. Samples from several of the wells where 1,2,3-TCP was detected by low-concentration-level analysis during resampling were not analyzed for 1,2,3-TCP using a low-level method during initial sampling. Most detections of nutrients and trace elements in samples from trend wells were less than health-based benchmarks during both sampling periods. Exceptions include nitrate, arsenic, boron, and vanadium, all detected at concentrations greater than their health-based benchmarks in at least one well during both sampling periods, and molybdenum, detected at concentrations greater than its health-based benchmark during resampling only. The isotopic ratios of oxygen and hydrogen in water and tritium and carbon-14 activities generally changed little between sampling periods, suggesting that the predominant sources and ages of groundwater in most trend wells were consistent between the sampling periods.

Hydrodynamic modelling of the microbial water quality in a drinking water source as input for risk reduction management

NASA Astrophysics Data System (ADS)

Sokolova, Ekaterina; Pettersson, Thomas J. R.; Bergstedt, Olof; Hermansson, Malte

2013-08-01

To mitigate the faecal contamination of drinking water sources and, consequently, to prevent waterborne disease outbreaks, an estimation of the contribution from different sources to the total faecal contamination at the raw water intake of a drinking water treatment plant is needed. The aim of this article was to estimate how much different sources contributed to the faecal contamination at the water intake in a drinking water source, Lake Rådasjön in Sweden. For this purpose, the fate and transport of faecal indicator Escherichia coli within Lake Rådasjön were simulated by a three-dimensional hydrodynamic model. The calibrated hydrodynamic model described the measured data on vertical temperature distribution in the lake well (the Pearson correlation coefficient was 0.99). The data on the E. coli load from the identified contamination sources were gathered and the fate and transport of E. coli released from these sources within the lake were simulated using the developed hydrodynamic model, taking the decay of the E. coli into account. The obtained modelling results were compared to the observed E. coli concentrations at the water intake. The results illustrated that the sources that contributed the most to the faecal contamination at the water intake in Lake Rådasjön were the discharges from the on-site sewers and the main inflow to the lake - the river Mölndalsån. Based on the modelling results recommendations for water producers were formulated. The study demonstrated that this modelling approach is a useful tool for estimating the contribution from different sources to the faecal contamination at the water intake of a drinking water treatment plant and provided decision-support information for the reduction of risks posed to the drinking water source.

Urban Water Services in Fragile States: An Analysis of Drinking Water Sources and Quality in Port Harcourt, Nigeria, and Monrovia, Liberia.

PubMed

Kumpel, Emily; Albert, Jeff; Peletz, Rachel; de Waal, Dominick; Hirn, Maximilian; Danilenko, Alexander; Uhl, Vincent; Daw, Ashish; Khush, Ranjiv

2016-07-06

Establishing and maintaining public water services in fragile states is a significant development challenge. In anticipation of water infrastructure investments, this study compares drinking water sources and quality between Port Harcourt, Nigeria, and Monrovia, Liberia, two cities recovering from political and economic instability. In both cities, access to piped water is low, and residents rely on a range of other private and public water sources. In Port Harcourt, geographic points for sampling were randomly selected and stratified by population density, whereas in Monrovia, locations for sampling were selected from a current inventory of public water sources. In Port Harcourt, the sampling frame demonstrated extensive reliance on private boreholes and a preference, in both planned and unplanned settlements, for drinking bottled and sachet water. In Monrovia, sample collection focused on public sources (predominantly shallow dug wells). In Port Harcourt, fecal indicator bacteria (FIB) were detected in 25% of sources (N = 566), though concentrations were low. In Monrovia, 57% of sources contained FIB and 22% of sources had nitrate levels that exceeded standards (N = 204). In Monrovia, the convenience of piped water may promote acceptance of the associated water tariffs. However, in Port Harcourt, the high prevalence of self-supply and bottled and sachet drinking water suggests that the consumer's willingness to pay for ongoing municipal water supply improvements may be determined by service reliability and perceptions of water quality. © The American Society of Tropical Medicine and Hygiene.

Urban Water Services in Fragile States: An Analysis of Drinking Water Sources and Quality in Port Harcourt, Nigeria, and Monrovia, Liberia

PubMed Central

Kumpel, Emily; Albert, Jeff; Peletz, Rachel; de Waal, Dominick; Hirn, Maximilian; Danilenko, Alexander; Uhl, Vincent; Daw, Ashish; Khush, Ranjiv

2016-01-01

Establishing and maintaining public water services in fragile states is a significant development challenge. In anticipation of water infrastructure investments, this study compares drinking water sources and quality between Port Harcourt, Nigeria, and Monrovia, Liberia, two cities recovering from political and economic instability. In both cities, access to piped water is low, and residents rely on a range of other private and public water sources. In Port Harcourt, geographic points for sampling were randomly selected and stratified by population density, whereas in Monrovia, locations for sampling were selected from a current inventory of public water sources. In Port Harcourt, the sampling frame demonstrated extensive reliance on private boreholes and a preference, in both planned and unplanned settlements, for drinking bottled and sachet water. In Monrovia, sample collection focused on public sources (predominantly shallow dug wells). In Port Harcourt, fecal indicator bacteria (FIB) were detected in 25% of sources (N = 566), though concentrations were low. In Monrovia, 57% of sources contained FIB and 22% of sources had nitrate levels that exceeded standards (N = 204). In Monrovia, the convenience of piped water may promote acceptance of the associated water tariffs. However, in Port Harcourt, the high prevalence of self-supply and bottled and sachet drinking water suggests that the consumer's willingness to pay for ongoing municipal water supply improvements may be determined by service reliability and perceptions of water quality. PMID:27114291

Searching for Terrain Softening near Mercury's North Pole

NASA Technical Reports Server (NTRS)

Cobian, P. S.; Vilas, F.; Lederer, S. M.; Barlow, N. G.

2004-01-01

In 1999, following the initial discovery of radar bright craters near both poles of Mercury measured the depth-todiameter (d/D) ratios of 170 impact craters in Mariner 10 images covering four different regions on Mercury s surface. Rapid softening of crater structure, indicated by lower d/D ratios, could indicate the possibility of subsurface water ice in Mercury's terrain originating from an internal source in the planet. Their study included 3 specific radar bright craters suggested to contain ice. They concluded that no terrain softening was apparent, and a rapidly emplaced exogenic water source was the most likely source for the proposed ice in these craters. Recent radar observations of the Mercurian North pole have pinpointed many additional radar bright areas with a resolution 10x better than previous radar measurements, and which correlate with craters imaged by Mariner 10. These craters are correlated with regions that are permanently shaded from direct sunlight, and are consistent with observations of clean water ice. We have expanded the initial study by Barlow et al. to include d/D measurements of 12 craters newly identified as radar bright at latitudes poleward of +80o. The radar reflectivity resemblances to Mars south polar cap and echoes from three icy Galilean satellites suggest that these craters too may have polar ice on Mercury. The effect of subsurface H20 on impact craters is a decrease in its d/D ratio, and softening of crater rims over a period of time. The study of Barlow et al., focused on determining the d/D ratios of 170 impact craters in the Borealis (north polar), Tolstoj (equatorial), Kuiper (equatorial), and Bach (south polar) quadrangles. This work focuses on the newly discovered radar bright craters, investigating their d/D ratios as an expansion of the earlier work..We compare our results to the statistical results from Barlow et al. here. With the upcoming Messenger spacecraft mission to Mercury, this is an especially timely study whose result could potentially help the Messenger team as they develop a mission strategy.

Assessing and managing water scarcity within the Nile River Transboundary Basin

NASA Astrophysics Data System (ADS)

Butts, M. B.; Wendi, D.; Jessen, O. Z.; Riegels, N. D.

2012-04-01

The Nile Basin is the main source of water in the North Eastern Region of Africa and is perhaps one of the most critical river basins in Africa as the riparian countries constitute 40% of the population on the continent but only 10% of the area. This resource is under considerable stress with rising levels of water scarcity, high population growth, watershed degradation, and loss of environmental services. The potential impacts of climate change may significantly exacerbate this situation as the water resources in the Nile Basin are critically sensitive to climate change (Conway, Hanson, Doherty, & Persechino, 2007). The motivation for this study is an assessment of climate change impacts and adaptation potential for floods and droughts within the UNEP project "Adapting to climate change induced water stress in the Nile River Basin", supported by SIDA. This project is being carried out as collaboration between DHI, the UK Met Office, and the Nile Basin Initiative (NBI). The Nile Basin exhibits highly diverse climatological and hydrological characteristics. Thus climate change impacts and adaptive capacity must be addressed at both regional and sub-basin scales. While the main focus of the project is the regional scale, sub-basin scale modelling is required to reflect variability within the basin. One of the major challenges in addressing this variability is the scarcity of data. This paper presents an initial screening modelling study of the water balance of the Nile Basin along with estimates of expected future impacts of climate change on the water balance. This initial study is focussed on the Ethiopian Highlands and the Lake Victoria regions, where the impact of climate change on rainfall is important. A robust sub-basin based monthly water balance model is developed and applied to selected sub-basins. The models were developed and calibrated using publicly available data. One of the major challenges in addressing this variability within the basin is the scarcity of spatial data and the results for the Kagera sub-basin show that it is important to represent the spatial distribution of the hydro-geographic characteristics such as rainfall, soil type, etc., in order to develop a reasonable representation of the water balance. These initial results show that the changes in the water balance and flow regime under climate change exhibit large uncertainty. From an examination the flow duration curves, however, there seems to be a consensus, based on an ensemble of climate projections, that flows will increase slightly the short term (2011-2030) and decrease significantly in the long term 2080-2099. The large uncertainties together with the natural variability in the Nile suggest that there is a strong need to maximise adaptive capacity with the region.

Separating Atmospheric and Surface Contributions in Hyperspectral Imager for the Coastal Ocean (HICO) Scenes using Informed Non-Negative Matrix Factorization

NASA Astrophysics Data System (ADS)

Wright, L.; Coddington, O.; Pilewskie, P.

2016-12-01

Hyperspectral instruments are a growing class of Earth observing sensors designed to improve remote sensing capabilities beyond discrete multi-band sensors by providing tens to hundreds of continuous spectral channels. Improved spectral resolution, range and radiometric accuracy allow the collection of large amounts of spectral data, facilitating thorough characterization of both atmospheric and surface properties. These new instruments require novel approaches for processing imagery and separating surface and atmospheric signals. One approach is numerical source separation, which allows the determination of the underlying physical causes of observed signals. Improved source separation will enable hyperspectral imagery to better address key science questions relevant to climate change, including land-use changes, trends in clouds and atmospheric water vapor, and aerosol characteristics. We developed an Informed Non-negative Matrix Factorization (INMF) method for separating atmospheric and surface sources. INMF offers marked benefits over other commonly employed techniques including non-negativity, which avoids physically impossible results; and adaptability, which tailors the method to hyperspectral source separation. The INMF algorithm is adapted to separate contributions from physically distinct sources using constraints on spectral and spatial variability, and library spectra to improve the initial guess. We also explore methods to produce an initial guess of the spatial separation patterns. Using this INMF algorithm we decompose hyperspectral imagery from the NASA Hyperspectral Imager for the Coastal Ocean (HICO) with a focus on separating surface and atmospheric signal contributions. HICO's coastal ocean focus provides a dataset with a wide range of atmospheric conditions, including high and low aerosol optical thickness and cloud cover, with only minor contributions from the ocean surfaces in order to isolate the contributions of the multiple atmospheric sources.

Sci-Thur PM – Brachytherapy 01: Fast brachytherapy dose calculations: Characterization of egs-brachy features to enhance simulation efficiency

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chamberland, Marc; Taylor, Randle E.P.; Rogers, Da

2016-08-15

Purpose: egs-brachy is a fast, new EGSnrc user-code for brachytherapy applications. This study characterizes egs-brachy features that enhance simulation efficiency. Methods: Calculations are performed to characterize efficiency gains from various features. Simulations include radionuclide and miniature x-ray tube sources in water phantoms and idealized prostate, breast, and eye plaque treatments. Features characterized include voxel indexing of sources to reduce boundary checks during radiation transport, scoring collision kerma via tracklength estimator, recycling photons emitted from sources, and using phase space data to initiate simulations. Bremsstrahlung cross section enhancement (BCSE), uniform bremsstrahlung splitting (UBS), and Russian Roulette (RR) are considered for electronicmore » brachytherapy. Results: Efficiency is enhanced by a factor of up to 300 using tracklength versus interaction scoring of collision kerma and by up to 2.7 and 2.6 using phase space sources and particle recycling respectively compared to simulations in which particles are initiated within sources. On a single 2.5 GHz Intel Xeon E5-2680 processor cor, simulations approximating prostate and breast permanent implant ((2 mm){sup 3} voxels) and eye plaque ((1 mm){sup 3}) treatments take as little as 9 s (prostate, eye) and up to 31 s (breast) to achieve 2% statistical uncertainty on doses within the PTV. For electronic brachytherapy, BCSE, UBS, and RR enhance efficiency by a factor >2000 compared to a factor of >10{sup 4} using a phase space source. Conclusion: egs-brachy features provide substantial efficiency gains, resulting in calculation times sufficiently fast for full Monte Carlo simulations for routine brachytherapy treatment planning.« less

Prevalence, characteristics and correlates of enteric pathogenic protozoa in drinking water sources in Molyko and Bomaka, Cameroon: a cross-sectional study.

PubMed

Nsoh, Fuh Anold; Wung, Buh Amos; Atashili, Julius; Benjamin, Pokam Thumamo; Marvlyn, Eba; Ivo, Keumami Katte; Nguedia, Assob Jules Clément

2016-11-08

Access to potable water remains a major challenge particularly in resource-limited settings. Although the potential contaminants of water are varied, enteric pathogenic protozoa are known to cause waterborne diseases greatly. This study aimed at investigating the prevalence, characteristics and correlates of enteric pathogenic protozoa in drinking water sources in Buea, Cameroon. A cross-sectional study was conducted using 155 water samples collected from various drinking sources (boreholes, springs, taps and wells). Each sample was subjected to physicochemical examinations (pH, turbidity, odour and sliminess) and parasitological analysis (wet mount, modified Ziehl-Neelsen stain) to determine the presence of enteric pathogenic protozoa. A data collection tool was used to note characteristics of collected samples and the data was analysed using EPI-INFO Version 3.5.3. The overall prevalence of enteric pathogenic protozoa in water sources was 62.6 %. Eight species of enteric protozoa were observed with Cryptosporidium parvum being the most predominant (45.8 %). Spring water was the most contaminated source with enteric protozoa (85.7 %) while pipe borne water had all eight species of protozoa identified. A pH of 6 was the only significant factor associated with the prevalence of these pathogens in water sources. The prevalence of enteric protozoa in water sources in Molyko and Bomaka is high, spring water is the most contaminated water source and Cryptosporidium parvum is the most common protozoa contaminating water. A water pH of 6 is associated to the prevalence of protozoa. Community members need to be educated to treat water before drinking to avoid infection by enteric protozoa in water and further studies with larger samples of water need to be conducted to find other correlates of the presence of protozoa in water.

All coliforms are not created equal: A comparison of the effects of water source and in-house water contamination on Infantile Diarrheal Disease

NASA Astrophysics Data System (ADS)

VanDerslice, James; Briscoe, James

1993-07-01

Storing drinking water in the home is common in the developing world. Several studies have documented increased concentrations of fecal coliforms during household storage. This has led to the belief that in-house water contamination is an important transmission route for enteric pathogens and, moreover, that improving water source quality is not warranted until that quality can be maintained in the home. We contend that in-house water contamination does not pose a serious risk of diarrhea because family members would likely develop some level of immunity to pathogens commonly encountered in the household environment. Even when there is no such immunity, transmission of these pathogens via stored water may be inefficient relative to other household transmission routes, such as person-to-person contact or food contamination. A contaminated water source poses much more of a risk since it may introduce new pathogens into the household, The effects of water source and in-house contamination on diarrheal disease are estimated for 2355 Filipino infants. The results confirm our hypothesis: contaminated water sources pose a serious risk of diarrhea while contamination of drinking water in the home does not. Water boiling is shown to eliminate the risk of diarrhea due to water source contamination. The results imply that improvements in water source quality are more important than improving water storage practices.

Water Source Pollution and Disease Diagnosis in a Nigerian Rural Community.

ERIC Educational Resources Information Center

Sangodoyin, A. Y.

1991-01-01

Samples from five water sources (spring, borehole, pond, stream, and well) in rural Nigerian communities were tested. Results include source reliabilities in terms of water quality and quantity, pollution effects upon water quality, epidemiological effects related to water quantity and waste disposal, and impact of water quality improvement upon…