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1

Toxicity Identification Evaluation (Phase I) of water and sediment samples from a tropical reservoir contaminated with industrial and domestic effluents.  

PubMed

The Funil Reservoir (Rio de Janeiro State, Brazil) is an environment degraded by constant discharge of nutrients and pollution coming from the most industrialized region of the country. As a consequence of eutrophication, there are continuous cyanobacteria blooms, which cause acute and chronic toxicity to zooplankton. In this context, Phase I of Toxicity Identification Evaluation (TIE) was performed on Daphnia similis using water and interstitial water from the reservoir, with the aim of identifying classes of compounds responsible for toxicity. The results indicated that water toxicity was due to cyanobacteria resulting from blooms in the reservoir and surfactants. Metals, especially copper, contributed to sediment toxicity. This research is the first attempt to describe the nature of toxicity in this reservoir using this method. PMID:25103213

Matos, Mariana de F; Botta, Clarice Maria Rispoli; Fonseca, Ana Lúcia

2014-11-01

2

Domestic wash water reclamation  

NASA Technical Reports Server (NTRS)

System consists of filtration unit, reverse-osmosis module, tanks, pumps, plumbing, and various gauges, meters, and valves. After water is used in washing machine or shower, it is collected in holding tank. Water is pumped through series of five particulate filters. Pressure tank supplies processed water to commode water closet.

Hall, J. B., Jr.; Batten, C. E.; Wilkins, J. R.

1974-01-01

3

STATE OF CALIFORNIA DOMESTIC HOT WATER (DHW)  

E-print Network

- presence of either a time control or a time/temperature control DECLARATION STATEMENT · I certify underSTATE OF CALIFORNIA DOMESTIC HOT WATER (DHW) CEC- CF-6R-MECH-01 (Revised 08/09) CALIFORNIA ENERGY COMMISSION INSTALLATION CERTIFICATE CF-6R-MECH-01 Domestic Hot Water (DHW) (Page 1 of 3) Site Address

4

Domestic water conservation potential in Saudi Arabia  

NASA Astrophysics Data System (ADS)

Domestic water conservation in arid climates can result in efficient utilization of existing water supplies. The impacts of conservation measures such as the installation of water-saving devices, water metering and pricing schemes, water rationing and public awareness programs, strict plumbing codes, penalties for wasting water, programs designed to reduce leakage from public water lines and within the home, water-efficient landscaping, economic and ethical incentives are addressed in detail. Cost savings in arid climates, with particular reference to Saudi Arabia, in relation to some conservation techniques, are presented. Water conservation technology and tentative demonstration and implementation of water conservation programs are discussed.

Abdulrazzak, Mohammed J.; Khan, Muhammad Z. A.

1990-03-01

5

Behavior of di(2-ethylhexyl) phthalate discharged from domestic waste water into aquatic environment.  

PubMed

The behavior of di(2-ethylhexyl) phthalate (DEHP) discharged from domestic waste water into river water, sediment and submerged aquatic vegetation was investigated. The concentrations of DEHP were found to be between 8-25 microg L(-1) in river water, 1,000-2,000 microg kg(-1) in sediment and less than 20-2,000 microg kg(-1) in submerged aquatic vegetation. The experiments performed in laboratory were on the biodegradation of DEHP in water and sediment, and also adsorption equilibrium of DEHP between water and sediment. The results obtained from the investigations made it clear that the high enrichment of DEHP from water to sediment was caused from not only its high adsorptive potential but also slow degradation in sediment. PMID:16395478

Yuwatini, Erini; Hata, Noriko; Taguchi, Shigeru

2006-01-01

6

SOLAR DOMESTIC WATER HEATERS PERFORMANCE IN SYDNEY  

Microsoft Academic Search

'ABSTRACT The performance of solar domestic water heaters was investigated as part of two projects carried out in Sydney in 1983\\/84. One project involved controlled testing of 9 of the most common systems so that comparative performance could be determined. The second project involved monitoring 12 solar water heaters installed in the Housing Commission of N.S.W. Bonnyrig Solar Village. The

G. L. MORRISON

7

Economic valuation of domestic water uses.  

PubMed

There are many reasons of concern about the quality of water for domestic uses. The strategic goals of water tariffs must include savings, efficient management and equity in order to optimise availability of the best quality water. The main domestic uses of water are food preparation, personal hygiene and household cleaning; not all of them need the same quality, and for some of them there are even potential substitutes. In order to contribute to this debate, we need to know how these different uses are valued by direct users. This article focuses on eliciting values for different domestic uses, using discrete choice experiments. As far as we know, this is the first time that a differentiated valuation per use has been defined. The paper introduces three innovations in the design of the experiment. The design takes into account decisive variables in household water consumption, such as family size, together with the consumption level, and the options offered in the choice task are combinations of different prices for each of the uses. A latent class model with both common and class-specific random parameters is applied to better account for the influence of heterogeneity in the respondents' choices. The results show that the most valued use depends on the consumption level class. PMID:24333993

Justes, Antón; Barberán, Ramón; Farizo, Begoña A

2014-02-15

8

Quantifying Urban Water Subsidies with Hydrological Tracers of Domestic Water  

NASA Astrophysics Data System (ADS)

Connections between urban hydrological systems and human water infrastructure are well established. Interactions between these systems occur at a wide range of scales, from large inter-basin transfers to individual leaking pipes. However, much of the interest in these connections arises from practical considerations, for example, substantially altered in-stream flow or the presence/absence of sewage in surface water systems. Less recognized is that in smaller urban catchments, daily water flux through human water distribution systems is often much larger than low flow surface water flux from the catchment. As infrastructure ages and cross-connections grow, transfers from the substantial human fluxes to the catchment will increasingly subsidize urban water budgets. Tools for quantifying the contribution of this subsidy to urban hydrological systems can clarify both practical questions for urban managers and our understanding of flow generation in catchments. Stream water chemistry from a multi-year sampling campaign in Nine Mile Run (Pittsburgh, PA) is used to examine potential hydrological tracers of human domestic water. In particular, we examine the use of fluoride added in precise quantities as a dental health supplement as a tracer of human domestic water (e.g., drinking and waste water). While fluoride is not necessarily a conservative tracer, equilibrium reactions governing fluoride solubility generally require substantially higher cationic concentrations than those observed in surface water chemistry. Further, during periods where human subsidies dominate (e.g., water line breaks or hydrant flushes discharging to the stream) fluoride concentrations generally approach the concentration added to domestic water. We use multiple modeling approaches to demonstrate the appropriateness of fluoride as a tracer, infer contributions of human domestic water to the hydrologic budget, and explore fluoride dynamics in the Nine Mile Run basin. A fluoride tracer is particularly exciting due to applicability in a large number of urban systems fluoridating drinking waters and due to robust, high-frequency measurement capacity via off-the-shelf drinking water treatment technologies.

Bain, D. J.; Sikora, M. T.; Wozniak, E.; Fisher, K. R.; Carr, J.; Elliott, E. M.

2011-12-01

9

Socioeconomic differentials and availability of domestic water in South Africa  

Microsoft Academic Search

The past few decades has seen massive efforts to increasing provision of domestic water. However, water is still unavailable to many people most of them located in sub-Saharan Africa, South Asia and East Asia. Furthermore, availability of water varies greatly both spatially and temporary. While other people pay so dearly for domestic water others have an easy access to adequate

Esther W. Dungumaro

2007-01-01

10

Contaminated Sediments in Water  

MedlinePLUS

... Water Protection Stormwater Vessel Discharge Wastewater Programs Watershed Management Resources & Performance Science & Technology Water Infrastructure What You Can Do News Feeds Podcasts EPA Mobile News by Email Widgets EPA Home Privacy and Security Notice Contact Us Last updated on Thursday, July ...

11

STATE OF CALIFORNIA SOLAR DOMESTIC HOT WATER SYSTEMS (SDHW)  

E-print Network

STATE OF CALIFORNIA SOLAR DOMESTIC HOT WATER SYSTEMS (SDHW) CEC- CF-6R-MECH-02 (Revised 08/09) CALIFORNIA ENERGY COMMISSION INSTALLATION CERTIFICATE CF-6R-MECH-02 Solar Domestic Hot Water Systems (SDHW 2009 SOLAR HOT WATER HEATING SYSTEMS: SRCC Certified Mfr Name & Model Number Net Solar Fraction (from

12

Accounting for Water Insecurity in Modeling Domestic Water Demand  

NASA Astrophysics Data System (ADS)

Water demand management uses price elasticity estimates to predict consumer demand in relation to water pricing changes, but studies have shown that many additional factors effect water consumption. Development scholars document the need for water security, however, much of the water security literature focuses on broad policies which can influence water demand. Previous domestic water demand studies have not considered how water security can affect a population's consumption behavior. This study is the first to model the influence of water insecurity on water demand. A subjective indicator scale measuring water insecurity among consumers in the Palestinian West Bank is developed and included as a variable to explore how perceptions of control, or lack thereof, impact consumption behavior and resulting estimates of price elasticity. A multivariate regression model demonstrates the significance of a water insecurity variable for data sets encompassing disparate water access. When accounting for insecurity, the R-squaed value improves and the marginal price a household is willing to pay becomes a significant predictor for the household quantity consumption. The model denotes that, with all other variables held equal, a household will buy more water when the users are more water insecure. Though the reasons behind this trend require further study, the findings suggest broad policy implications by demonstrating that water distribution practices in scarcity conditions can promote consumer welfare and efficient water use.

Galaitsis, S. E.; Huber-lee, A. T.; Vogel, R. M.; Naumova, E.

2013-12-01

13

Socioeconomic differentials and availability of domestic water in South Africa  

NASA Astrophysics Data System (ADS)

The past few decades has seen massive efforts to increasing provision of domestic water. However, water is still unavailable to many people most of them located in sub-Saharan Africa, South Asia and East Asia. Furthermore, availability of water varies greatly both spatially and temporary. While other people pay so dearly for domestic water others have an easy access to adequate clean water and sanitation. Accessibility and affordability of domestic water and sanitation is determined by a great variety of factors including socioeconomic status of households. The main objective of the paper is to inform on factors which need to be taken into account when coming up with projects to provide domestic water. It is more critical when the issue of water pricing comes into the equation. Water pricing has many facets, including equity, willingness to pay and affordability. In this premise, it is deemed important to understand the socioeconomic characteristics of the people before deciding on the amount of money they will have to pay for water consumption. It is argued that understanding people’s socioeconomic situation will greatly help to ensure that principles of sustainability and equity in water allocation and pricing are achieved. To do so, the paper utilized 2002 South Africa General Household Survey (GHS), to analyze socioeconomic variables and availability of domestic water. Analysis was mainly descriptive. However, logistic regression analysis was also utilized to determine the likelihood of living in a household that obtain water from a safe source. The study found that there is a strong relationship between availability of domestic water and socioeconomic conditions. Economic status, household size and to a lesser extent gender of head of household were found to be strong predictors of living in a household which obtained water from a safe source. The paper recommends that needs and priorities for interventions in water provision should take into account socioeconomic status of households.

Dungumaro, Esther W.

14

AMBIENT WATER, POREWATER, AND SEDIMENT  

EPA Science Inventory

Sediment assessments may be performed for a variety of purposes; these include: dredging and dredged sediment disposal, for evaluations of sediments as a capping material, to determine sediment quality, to assess biological impairment and to assess the status of environment monit...

15

Assessment of domestic water quality: case study, Beirut, Lebanon.  

PubMed

In urban cities, the environmental services are the responsibility of the public sector, where piped water supply is the norm for urban household. Likewise, in Beirut City (capital of Lebanon) official water authorities are the main supplier of domestic water through a network of piping system that leaks in many areas. Beirut City and its suburbs are overpopulated since it is the residence of 1/3 of the Lebanese citizens. Thus, Beirut suffers deficiency in meeting its water demand. Water rationing, as a remedial action, is firmly established since four decades by the Lebanese Water Authorities. Consumers resorted then to private wells to supplement their domestic water needs. Consequently, household water quality is influenced by external factors relating to well water characteristics and internal factors depending on the types of the pipes of the distribution network and cross connections to sewer pipes. These factors could result in chemical and microbial contamination of drinking water. The objective of this study is to investigate domestic water quality variation in Beirut City emerging form the aforementioned factors. The presented work encircles a typical case study of Beirut City (Ras Beirut). Results showed deterioration pattern in domestic water quality. The predicted metal species and scales within the water pipes of distribution network depended on water pH, hardness, sulfate, chloride, and iron. The corrosion of iron pipes mainly depended on Mg hardness. PMID:17380419

Korfali, Samira Ibrahim; Jurdi, Mey

2007-12-01

16

Exergy analysis of domestic-scale solar water heaters  

Microsoft Academic Search

Solar water heater is the most popular means of solar energy utilization because of technological feasibility and economic attraction compared with other kinds of solar energy utilization. Earlier assessments of domestic-scale solar water heaters were based on the first thermodynamic law. However, this kind of assessment cannot perfectly describe the performance of solar water heaters, since the essence of energy

Wang Xiaowu; Hua Ben

2005-01-01

17

Domestic applications for aerospace waste and water management technologies  

NASA Technical Reports Server (NTRS)

Some of the aerospace developments in solid waste disposal and water purification, which are applicable to specific domestic problems are explored. Also provided is an overview of the management techniques used in defining the need, in utilizing the available tools, and in synthesizing a solution. Specifically, several water recovery processes will be compared for domestic applicability. Examples are filtration, distillation, catalytic oxidation, reverse osmosis, and electrodialysis. Solid disposal methods will be discussed, including chemical treatment, drying, incineration, and wet oxidation. The latest developments in reducing household water requirements and some concepts for reusing water will be outlined.

Disanto, F.; Murray, R. W.

1972-01-01

18

Energy conservation in the production of domestic hot water  

NASA Astrophysics Data System (ADS)

Improvements in energy efficiency in existing buildings and the construction of energy efficient buildings are discussed with emphasis on water heating. Cost effective measures proposed include fitting an 80-mm insulating jacket to the hot water storage cylinder, using time switches, fitting thermostatic control systems to boiler based central heating, and storing domestic hot water at a lower temperature. Research into the recovery of heat from waste water, the use of cold water detergents, and the use of heat pumps is urged.

1981-12-01

19

Analysis Model for Domestic Hot Water Distribution Systems: Preprint  

SciTech Connect

A thermal model was developed to estimate the energy losses from prototypical domestic hot water (DHW) distribution systems for homes. The developed model, using the TRNSYS simulation software, allows researchers and designers to better evaluate the performance of hot water distribution systems in homes. Modeling results were compared with past experimental study results and showed good agreement.

Maguire, J.; Krarti, M.; Fang, X.

2011-11-01

20

Design package for solar domestic hot water system  

NASA Technical Reports Server (NTRS)

The initial design of a solar domestic hot water system is considered. The system performance specification and detailed design drawings are included. The hot water systems consist of the following subsystems: collector, storage, control, transport, auxiliary energy, and government-furnished site data acquisition. The two systems are installed at Tempe, Arizona, and San Diego, California.

1980-01-01

21

Design package for solar domestic hot water system  

SciTech Connect

Information used to evaluate the initial design of the Elcam, Inc., Solar Domestic Hot Water System is presented. Included are such items as the system performance specification, detailed design drawings and other information. Elcam, Inc., has developed two solar heated prototype hot water systems and two heat exchangers. The hot water systems consist of the following subsystems: collector, storage, control, transport, auxiliary energy, and government-furnished Site Data Acquisition. The two systems are installed at Tempe, Arizona, and San Diego, California.

None

1980-09-01

22

Marine Water And Sediment Monitoring In Washington  

Microsoft Academic Search

The Washington State Department of Ecology (Ecology) conducts several statewide monitoring programs including marine water and sediment monitoring. The marine water program, which encompasses Puget Sound and two coastal estuaries, was initiated in 1967. Since then, long-term monthly water quality data have been collected at over fifty-five stations. The goals of the program include characterizing spatial and temporal trends in

Carol Janzen; Pete Striplin

1991-01-01

23

Prototype solar domestic hot water systems  

NASA Technical Reports Server (NTRS)

Construction of a double wall heat exchanger using soft copper tube coiled around a hot water storage tank was completed and preliminary tests were conducted. Solar transport water to tank potable water heat exchange tests were performed with a specially constructed test stand. Work was done to improve the component hardware and system design for the solar water heater. The installation of both a direct feed system and a double wall heat exchanger system provided experience and site data to enable informative decisions to be made as the solar market expands into areas where freeze protection is required.

1978-01-01

24

CONTAMINANTS IN WATER AND SEDIMENT  

EPA Science Inventory

The Detroit River has experienced over a century of heavy contaminant discharges from industry and municipalities. The sources of contaminants vary, and include non-point sources, combined sewer overflows, point sources, tributaries, sediments, and upstream inputs. --- Demonst...

25

Automation of a solar domestic hot water heating system test  

Microsoft Academic Search

A minicomputer-based system for the automated testing of solar domestic hot water systems is described. This system was developed for use with the ASHRAE 95-P test method and the associated rating standard developed by the Tennessee Valley Authority for Middle Tennessee. The minicomputer controls the test and, currently, scans 12 channels of data every four seconds for each of up

G. T. Meares; W. W. Youngblood

1982-01-01

26

Uranium in US surface, ground, and domestic waters. Volume 2  

SciTech Connect

The report Uranium in US Surface, Ground, and Domestic Waters comprises four volumes. Volumes 2, 3, and 4 contain data characterizing the location, sampling date, type, use, and uranium conentrations of 89,994 individual samples presented in tabular form. The tabular data in volumes 2, 3, and 4 are summarized in volume 1 in narrative form and with maps and histograms.

Drury, J.S.; Reynolds, S.; Owen, P.T.; Ross, R.H.; Ensminger, J.T.

1981-04-01

27

NORTH PORTAL - DOMESTIC COLD WATER CALCULATION - CHANGE HOUSE FACILITY #5008  

SciTech Connect

The purpose of this design analysis and calculation is to determine the demand for domestic cold water and to size the supply main piping for the Change House Facility No.5008 in accordance with the Uniform Plumbing Code (Section 4.4.1) and US Department of Energy Order 6430.1A-1540 (Section 4.4.2).

S. Mastilovic

2000-03-02

28

Electrochemical chlorination for purifying domestic water supplies  

E-print Network

excessively by the electrolysis of water, Graphite was replaced by platinized-titanium as an anode material. This new anode experienced no detectable deterioration during the testing period, Much higher chlorine residuals were obtained with the platinized-titanium... of platinized-titanium anodes -'1 wheze chloride concentration in the water is 50 mg 1 or greater. ACKNOWLEDGEMENTS The author wishes to express sincere appreciation to Dr. Edward A, Hiler for his guidance, comments, and suggestions throughout...

Peters, Joseph Ludwig

1973-01-01

29

An Adaptive Fuzzy Algorithm for Domestic Hot Water Temperature Control of a Combi-Boiler  

Microsoft Academic Search

This paper describes an innovative adaptive fuzzy control (AFC) algorithm for regulating the domestic hot water temperature of a combi-boiler or instantaneous hot water heater when using a domestic hot water flow rate sensor. The AFC automatically learns the feedforward relationship between the domestic hot water flow rate and the gas valve position and adapts to process changes such as

Christine M. Haissig; Michael Woessner

2000-01-01

30

Solar energy for domestic water heating:system design criteria  

Microsoft Academic Search

Design criteria for solar energy domestic water heating applications are outlined. The following guidelines are presented for evaluating relative thermal performance of a collector for water heating applications: transmissivity of cover plates, 90% minimum; absorptivity of the absorber plate, 95% of the incident radiation; insulation of the back and sides of the collector housing, 0.05 Btu-hr\\/ft²\\/F; space between the cover

R. E. Hedden; T. A. King

1977-01-01

31

Use of tracers and isotopes to evaluate vulnerability of water in domestic wells to septic waste  

USGS Publications Warehouse

In Nebraska, a large number (>200) of shallow sand-point and cased wells completed in coarse alluvial sediments along rivers and lakes still are used to obtain drinking water for human consumption, even though construction of sand-point wells for consumptive uses has been banned since 1987. The quality of water from shallow domestic wells potentially vulnerable to seepage from septic systems was evaluated by analyzing for the presence of tracers and multiple isotopes. Samples were collected from 26 sand-point and perforated, cased domestic wells and were analyzed for bacteria, coliphages, nitrogen species, nitrogen and boron isotopes, dissolved organic carbon (DOC), prescription and nonprescription drugs, or organic waste water contaminants. At least 13 of the 26 domestic well samples showed some evidence of septic system effects based on the results of several tracers including DOC, coliphages, NH4+, NO3-, N2, ?? 15N[NO3-] and boron isotopes, and antibiotics and other drugs. Sand-point wells within 30 m of a septic system and <14 m deep in a shallow, thin aquifer had the most tracers detected and the highest values, indicating the greatest vulnerability to contamination from septic waste. Copyright ?? 2005 National Ground Water Association.

Verstraeten, I.M.; Fetterman, G.S.; Meyer, M.J.; Bullen, T.; Sebree, S.K.

2005-01-01

32

1. DOMESTIC WATER SUPPLY TREATMENT HOUSE, ON PENSTOCK ABOVE SAR1. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. DOMESTIC WATER SUPPLY TREATMENT HOUSE, ON PENSTOCK ABOVE SAR-1. VIEW TO NORTWEST. - Santa Ana River Hydroelectric System, SAR-1 Domestic Water Supply Treatment House, Redlands, San Bernardino County, CA

33

"ITM" (INLAND WATERS SEDIMENT TESTING MANUAL)  

EPA Science Inventory

EPA public web site providing the national sediment testing manual for dredged material proposed for discharge in waters of the U.S. Description from site: "The "Evaluation of Dredged Material Proposed for Dischage in Waters of the U.S. - Testing Manual", commonly referred to as...

34

Par Pond Fish, Water, and Sediment Chemistry  

SciTech Connect

The objectives of this report are to describe the Par Pond fish community and the impact of the drawdown and refill on the community, describe contaminant levels in Par Pond fish, sediments, and water and indicate how contaminant concentrations and distributions were affected by the drawdown and refill, and predict possible effects of future water level fluctuations in Par Pond.

Paller, M.H. [Westinghouse Savannah River Company, AIKEN, SC (United States); Wike, L.D.

1996-06-01

35

Review of domestic water conservation practices in Saudi Arabia  

NASA Astrophysics Data System (ADS)

The Kingdom of Saudi Arabian (KSA) has a substantial water shortage problem where water demand far exceeds water resources sustainable yields. This fact has motivated the Ministry of Water and Electricity (MOWE) to launch a massive water conservation awareness program to enhance water-using efficiency in the country. The MOWE among other water awareness activities has introduced a four-stage program of free distribution of water conservation tools. This research reviewed the domestic water conservation awareness program in Saudi Arabia and assessed the program performance through conducting questionnaire surveys. The latter was designed and implemented in Al-Khobar city in the Eastern Province to measure public awareness regarding water issues. The survey started on April 28, 2012, and continued for 3 weeks. A total of 197 questionnaires were completed. The survey results showed a relatively low awareness among respondents about water shortage problem in the Kingdom. A low percentage of respondents have water conservation tools installed in their houses, but a high percentage is willing to buy and install water conservation tools. The majority of respondents consider the water price low and are willing to pay more for water. The respondents' feedback highlighted the need to improve the current water conservation awareness program.

Ouda, Omar K. M.; Shawesh, Ahmad; Al-Olabi, Tareq; Younes, Firas; Al-Waked, Rafat

2013-12-01

36

Reliability assessment of solar domestic hot water systems  

Microsoft Academic Search

This paper presents reliability and mean-time-between-failure studies of six generic solar domestic hot water systems. Failure rate data for system components were obtained from product literature or from consumer product industries. Reliability block diagrams are employed for the analyses, and exponential distribution functions are assumed for individual components. Since some components do not operate continuously, a duty-cycle factor is developed

P. Y. Wang; R. M. Wolosewicz

1981-01-01

37

Estimated Domestic, Irrigation, and Industrial Water Use in Washington, 2000  

USGS Publications Warehouse

Since 1950, the U.S. Geological Survey has published a series of Circulars and other reports on the estimated use of water in the United States at 5-year intervals. This report presents State, regional, and county estimates of the amount of water used for domestic, irrigation, and industrial purposes in the State of Washington during the year 2000. Domestic water use was estimated to be 674 million gallons per day and the per-capita rate, 114 gallons per day. Crop-irrigation water use was estimated to be 3,005 million gallons per day and the application rate, 2.2 acre-feet per acre per year, or feet per year. Golf-course irrigation water use was estimated to be 23.6 million gallons per day and the application rate, 1.4 feet per year. Industrial water use was estimated to be 681 million gallons per day. Historically, these core categories account for about 92 percent of the estimated offstream water used in Washington.

Lane, R.C.

2004-01-01

38

Domestic water conservation practices in Tlemcen City (Algeria)  

NASA Astrophysics Data System (ADS)

During the last three decades, citizens of an Algerian city are concerned with the problem of drinking water supply. Time discontinuation service became the rule. The central idea of the analysis based on interviews is to assess the role of water in the organization of the relationship between habitat and users. The fundamental question is how users, in particular women, incorporate water in their daily lives due to rationing. Having to deal with the discontinuous and frequent weak water supply, the inhabitants of the city of Tlemcen who are connected to the water supply system, as well as those connected to the water system of all Algerian towns, have developed an internal water storage system to sort out this problem. The imposed rationing has proved to be expensive for consumers. The water shortage pushed the consumers to invest in relatively expensive storage and pumping facilities to satisfy their domestic needs. As the frequency of the water supply is on a two times per week basis, the survey reveals a discrepancy in terms of volumes consumed and stored by each household. The use of water depends on the individual storage facility and the frequency of the supply. The life of the households, particularly that of the housewives, depends on the availability of water and thus on the schedules of the Company of Production of Water "Algerian Des Eaux'' (ADE). This is particularly the case when they are supplied during the night.

Habi, Mohammed; Harrouz, Omar

2014-03-01

39

Numerical simulation of sediment related processes in water quality model  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sediment is a major nonpoint-source pollutant, and the exchange of materials between water and sediment is an important component of the lake eutrophication process. Suspended sediment increases water surface reflectivity and light attenuation in the water column. Nutrients can be absorbed to sedime...

40

The human right to water: the importance of domestic and productive water rights.  

PubMed

The United Nations (UN) Universal Declaration of Human Rights engenders important state commitments to respect, fulfill, and protect a broad range of socio-economic rights. In 2010, a milestone was reached when the UN General Assembly recognized the human right to safe and clean drinking water and sanitation. However, water plays an important role in realizing other human rights such as the right to food and livelihoods, and in realizing the Convention on the Elimination of All Forms of Discrimination against Women. These broader water-related rights have been recognized but have not yet been operationalized. This paper unravels these broader water-related rights in a more holistic interpretation of existing international human rights law. By focusing on an emerging approach to water services provision--known as 'domestic-plus' services--the paper argues how this approach operationalizes a comprehensive range of socio-economic rights in rural and peri-urban areas. Domestic-plus services provide water for domestic and productive uses around homesteads, which challenges the widespread practice in the public sector of planning and designing water infrastructure for a single-use. Evidence is presented to show that people in rural communities are already using their water supplies planned for domestic uses to support a wide range of productive activities. Domestic-plus services recognize and plan for these multiple-uses, while respecting the priority for clean and safe drinking water. The paper concludes that domestic-plus services operationalize the obligation to progressively fulfill a comprehensive range of indivisible socio-economic rights in rural and peri-urban areas. PMID:24337891

Hall, Ralph P; Van Koppen, Barbara; Van Houweling, Emily

2014-12-01

41

Domestic water and sanitation as water security: monitoring, concepts and strategy  

PubMed Central

Domestic water and sanitation provide examples of a situation where long-term, target-driven efforts have been launched with the objective of reducing the proportion of people who are water-insecure, most recently through the millennium development goals (MDGs) framework. Impacts of these efforts have been monitored by an increasingly evidence-based system, and plans for the next period of international policy, which are likely to aim at universal coverage with basic water and sanitation, are being currently developed. As distinct from many other domains to which the concept of water security is applied, domestic or personal water security requires a perspective that incorporates the reciprocal notions of provision and risk, as the current status of domestic water and sanitation security is dominated by deficiency This paper reviews the interaction of science and technology with policies, practice and monitoring, and explores how far domestic water can helpfully fit into the proposed concept of water security, how that is best defined, and how far the human right to water affects the situation. It is considered that they fit well together in terms both of practical planning of targets and indicators and as a conceptual framework to help development. The focus needs to be broad, to extend beyond households, to emphasize maintenance as well as construction and to increase equity of access. International and subnational monitoring need to interact, and monitoring results need to be meaningful to service providers as well as users. PMID:24080628

Bradley, David J.; Bartram, Jamie K.

2013-01-01

42

Water-sediment flow models for river reaches sediment related pollution control.  

PubMed

Hybrid water-sediment flow models for river reaches have been for predicting sediment and sediment related pollutions in water courses. The models are developed by combining sediment rating model and the Muskingum model applicable for a reach. The models incorporate sediment concentration and water discharge variables for a river reach; allow defining downstream sediment rating curve in terms of upstream water discharges. The model is useful in generating sediment concentration graph for a station having no water discharge records. The hybrid models provide forecasting forms that can be used to forecast downstream sediment concentration/water discharges 2kx time unit ahead. The forecasting models are useful for applications in real time namely, in the real time management of sediment related pollution in water courses and in issuing flood warning. Integration of sediment rating model and the Muskingum model increases model parameters and nonlinearity requiring efficient estimation technique for parameter identification. To identify parameters in the hybrid models genetic algorithm (GA) based optimization technique can be used. The new model relies on the Muskingum model, obey continuity requirement and the parameters can be used in the Muskingum model with water discharges to estimate/predict downstream water discharge values. The proposed model formulations are demonstrated for simulating and forecasting sediment concentration and water discharges in the Mississippi River Basin, USA. Model parameters are estimated using non-dominated sorting Genetic Algorithm II (NSGA-II). Model results show satisfactory model performances. PMID:24749192

Sil, Briti Sundar; Choudhury, Parthasarathi

2012-07-01

43

Occurrence of polychlorinated diphenyl sulfides (PCDPSs) in surface sediments and surface water from the Nanjing section of the Yangtze River.  

PubMed

Polychlorinated diphenyl sulfides (PCDPSs) are dioxin-like compounds that could induce various adverse effects to organisms. However, little is known about the occurrence of PCDPSs in the riverine environment. In the present study, the concentrations of twenty-one types of PCDPSs in the surface sediments and in surface water from the Nanjing section of the Yangtze River were examined. A total of 19 types of PCDPSs were detected and ?PCDPSs concentrations in surface sediment and surface water ranged from 0.10 to 6.90 ng/g and 0.18 to 2.03 ng/L, respectively. The 2,2',4,4',5-penta-CDPS was the dominant congener in sediment (19.9%) and 2,2',3,3'-tetra-CDPS was the most abundant congener in water (12.2%). The tetra-CDPSs were the dominant congeners both in sediment and in water. Compared with sediment, the percentage of lower chlorinated PCDPSs in water increased distinctly. Source analysis revealed that the PCDPSs in the sediment and in the water mainly came from chemical wastewater rather than domestic sewage. There was a significant linear correlation between ?PCDPS concentrations and sediment TOC contents, while no linear correlation existed between ?PCDPS concentrations and water DOC contents. This study demonstrated the prevalent contamination by PCDPSs in sediments and in water from the Nanjing section of the Yangtze River. PMID:25168171

Zhang, Xuesheng; Qin, Li; Qu, Ruijuan; Feng, Mingbao; Wei, Zhongbo; Wang, Liansheng; Wang, Zunyao

2014-10-01

44

NORTH PORTAL - DOMESTIC COLD WATER CALCULATION - CHANGE HOUSE FACILITY #5008  

SciTech Connect

The purpose of this design analysis and calculation is to determine the demand for domestic cold water and to size the supply main piping for the Change House Facility No.5008 in accordance with the Uniform Plumbing Code (Section 4.4.1) and U.S. Department of Energy Order 6430.1A-1540 (Section 4.4.2). The method used for the calculations is based on the Uniform Plumbing Code (UPC), Section 4.4.1. The first step is to determine the maximum pressure drop between the most remote cold water plumbing fixture and the main distribution supply. The developed length of pipe from the supply to the fixture is then determined from the plumbing drawings. The maximum pressure drop is then divided by the developed length which results in the friction loss per 100 feet of pipe. Equivalent fixture units are assigned from the UPC based on the actual fixture count which when totaled determines the water flow rate. The water flow rate and pressure drop are used to determine the pipe size based on a given velocity of flow.

R. Blackstone

1996-01-25

45

The Suburbanization of Water Scarcity in the Barcelona Metropolitan Region: Sociodemographic and Urban Changes Influencing Domestic Water Consumption  

Microsoft Academic Search

The metropolitan region of Barcelona is facing change in urban development patterns, sociodemographic structures, and domestic water use and management. In recent years, several drought alerts have been enacted and water restrictions applied, uncovering the fragile equilibrium between the demand and the supply of this resource. We find the literature on determinants of domestic water consumption to be strongly biased

Hug March; David Saurí

2010-01-01

46

Evaluation of a multifiltration water reclamation subsystem to reclaim domestic clothes wash water  

NASA Technical Reports Server (NTRS)

An evaluation has been performed of a multifiltration water reclamation subsystem to determine its capability to recover water from domestic clothes wash water. A total of 32.89 kg (72.5 lb) of clothes were washed during eight wash cycles which used 1.4 lb of detergent, 145 gallons of hot water and 133.9 gallons of cold water. Water recovered at a weighted average process rate of 3.81 gallons per hour met the majority of the 23 requirements established for potable water by the U.S. Public Health Service. Average power consumed during this evaluation was approximately 71 watt-hours per gallon of water recovered. Filter replacement, which was required primarily for the control of micro-organisms in the recovered water averaged 4.86 filters per 100 gallons of wash water processed. The subsystem removed approximately 98 percent and virtually 100 percent of the phosphates and surfactants, respectively, from the wash water.

Hall, J. B., Jr.

1973-01-01

47

Numerical Simulation of a Solar Domestic Hot Water System  

NASA Astrophysics Data System (ADS)

An innovative transient numerical model is presented for the simulation of a solar Domestic Hot Water (DHW) system. The solar collectors have been simulated by using a zerodimensional analytical model. The temperature distributions in the heat transfer fluid and in the water inside the tank have been evaluated by one-dimensional models. The reversion elimination algorithm has been used to include the effects of natural convection among the water layers at different heights in the tank on the thermal stratification. A finite difference implicit scheme has been implemented to solve the energy conservation equation in the coil heat exchanger, and the energy conservation equation in the tank has been solved by using the finite difference Euler implicit scheme. Energy conservation equations for the solar DHW components models have been coupled by means of a home-made implicit algorithm. Results of the simulation performed using as input data the experimental values of the ambient temperature and the solar irradiance in a summer day are presented and discussed.

Mongibello, L.; Bianco, N.; Di Somma, M.; Graditi, G.; Naso, V.

2014-11-01

48

TRACER STUDY OF SEDIMENT-WATER INTERACTIONS IN ESTUARIES  

EPA Science Inventory

Rates of sediment bioturbation and advective exchange of water across the sediment-water interface in Narragansett Bay, Rhode Island were studied by radioactive tracer experiments. The 'biological pumping rate' of water across the interface (.7 + or - .3 cc/sq cm day) was calcula...

49

Sediment tracers in water erosion studies: Current approaches and challenges  

Technology Transfer Automated Retrieval System (TEKTRAN)

The interest in the use of sediment tracers as a complementary tool to traditional water soil erosion or deposition measurements or assessment has increased due to the additional information they may provide such as sediment source identification and tracking of sediment movement over the landscape ...

50

Domestic wash-water reclamation using an aerospace-developed water recovery subsystem  

NASA Technical Reports Server (NTRS)

A prototype aerospace distillation water recovery subsystem was tested to determine its capability to recover potable water from domestic wash water. A total of 0.0994 cu m (26.25 gallons) of domestic wash water was processed over a 7-day period at an average process rate of 0.0146 cu m per day (3.85 gallons per day). The subsystem produced water that met all United States Public Health Standards for drinking water with the exception of two standards which could not be analyzed at the required sensitivity levels. Average energy consumption for this evaluation to maintain both the recovery process and microbial control in the recovered water was approximately 3366 kilowatt-hours per cubic meter (12.74 kilowatt-hours per gallon) of water recovered. This condition represents a worst case energy consumption since no attempt was made to recover heat energy in the subsystem. An ultraviolet radiation cell installed in the effluent line of the subsystem was effective in controlling coliform micro-organisms within acceptable levels for drinking water. The subsystem recovered virtually 100 percent of the available water in the waste-water process. In addition, the subsystem removed 99.6 percent and 98.3 percent of the surfactants and phosphate, respectively, from the wash water.

Hall, J. B., Jr.

1973-01-01

51

Expert Meeting Report: Recommendations for Applying Water Heaters in Combination Space and Domestic Water Heating Systems  

SciTech Connect

The topic of this meeting was 'Recommendations For Applying Water Heaters In Combination Space And Domestic Water Heating Systems.' Presentations and discussions centered on the design, performance, and maintenance of these combination systems, with the goal of developing foundational information toward the development of a Building America Measure Guideline on this topic. The meeting was held at the Westford Regency Hotel, in Westford, Massachusetts on 7/31/2011.

Rudd, A.; Ueno, K.; Bergey, D.; Osser, R.

2012-07-01

52

Benthic invertebrate bioassays with toxic sediment and pore water  

USGS Publications Warehouse

The relative sensitivities of bioassays to determine the toxicity of sediments were investigated and three methods of making the sample dilutions required to generate dose-response relationships were compared. The assays studied were: (a) Microtox(R), a 15-min assay of Photobacterium phosphoreum bioluminescence inhibition by pore water; (b) 48-h Daphnia magna lethality test in pore water; (c) 10-d subchronic assay of lethality to and reduction of weight gain by Chironomus tentans performed in either whole sediment or pore water; (d) 168-h acute lethality assay of Hexagenia limbata in either whole sediment or pore water. The three methods of diluting sediments were: (a) extracting pore water from the toxic location and dilution with pore water from the control station; (b) diluting whole sediment from the toxic location with control whole sediment from a reference location, then extracting pore water; and (c) diluting toxic, whole sediment with whole sediment from a reference location, then using the whole sediment in bioassays. Based on lethality, H. limbata was the most sensitive organism to the toxicity of Detroit River sediment. Lethality of D. magna was similar to that of H. limbata in whole sediment and can be used to predict effects of whole sediment toxicity to H. limbata. The concentration required to cause a 50% reduction in C. tentans growth (10-d EC50) was approximately that which caused 50% lethality of D. magna (48-h LC50) and was similar to the toxicity that restricts benthic invertebrate colonization of contaminated sediments. While the three dilution techniques gave similar results with some assays, they gave very different results in other assays. The dose-response relationships determined by the three dilution techniques would be expected to vary with sediment, toxicant and bioassay type, and the dose-response relationship derived from each technique needs to be interpreted accordingly.

Giesy, John P.; Rosiu, Cornell J.; Graney, Robert L.; Henry, Mary G.

1990-01-01

53

TOXICITY EVALUATION OF LOWER FOX RIVER WATER AND SEDIMENTS  

EPA Science Inventory

Many persistent, xenobiotic compounds have been identified from Lower Fox River water, biota, sediment, and effluent discharges; some of which are suspected of causing adverse effects to aquatic organisms. Water and sediment were collected as grab samples from the Lower Fox River...

54

DEVELOPING WATER QUALITY CRITERIA FOR SUSPENDED AND BEDDED SEDIMENTS  

EPA Science Inventory

The U.S. EPA?s Framework for Developing Suspended and Bedded Sediments (SABS) Water Quality Criteria (SABS Framework) is a nationally-consistent process for developing ambient sediment quality criteria for surface waters. The SABS Framework accommodates natural variation among wa...

55

Cold-Climate Solar Domestic Hot Water Systems Analysis  

SciTech Connect

The Solar Heating and Lighting Sub-program has set the key goal to reduce the cost of saved energy [Csav, defined as (total cost, $)/(total discounted savings, kWh_thermal)] for solar domestic water heaters (SDWH) by at least 50%. To determine if this goal is attainable and prioritize R&D for cold-climate SDWH, life-cycle analyses were done with hypothetical lower-cost components in glycol, drainback, and thermosiphon systems. Balance-of-system (BOS, everything but the collector) measures included replacing metal components with polymeric versions and system simplification. With all BOS measures in place, Csav could be reduced more than 50% with a low-cost, selectively-coated, glazed polymeric collector, and slightly less than 50% with either a conventional selective metal-glass or a non-selective glazed polymer collector. The largest percent reduction in Csav comes from replacing conventional pressurized solar storage tanks and metal heat exchangers with un-pressurized polymer tanks with immersed polymer heat exchangers, which could be developed with relatively low-risk R&D.

Burch, J.; Salasovich, J.; Hillman, T.

2005-11-01

56

Solar Domestic Hot Water System manual for Day's Inn, Garland, Texas  

NASA Technical Reports Server (NTRS)

The Solar Domestic Hot Water System installed at Day's Inn, I-30 and 6222 Beltline, Garland, Texas, is described. The system is a solar collector array used to provide from 39.9 percent in December, to 84.7 percent in August, of the domestic hot water usage of the Day's Inn in Garland, Texas. The system is an automatic draindown design employing an atmospheric vented storage tank for storing the hot water collected by the 998 sq. ft. collector array.

1981-01-01

57

Promising freeze protection alternatives in solar domestic hot water systems  

SciTech Connect

Since the gains associated with solar thermal energy technologies are comparatively small in relation to the required capital investment, it is vital to maximize conversion efficiency. While providing the necessary function of freeze protection, the heat exchanger commonly included in solar domestic water heating systems represents a system inefficiency. This thesis explores two alternate methods of providing freeze protection without resorting to a heat exchanger. Commonly, collectors are made of rigid copper tubes separated by copper or aluminum fins. Cracking damage can occur when water is allowed to freeze and expand inside the non compliant tubes. The possibility of making collectors out of an elastic material was investigated and shown to be effective. Since unlike copper, elastomers typically have low thermal conductivities, the standard collector performance prediction equations do not apply. Modified thermal performance prediction equations were developed which can be used for both low and high thermal conductivity materials to provide accurate predictions within a limited range of plate geometries. An elastomeric collector plate was then designed and shown to have comparable performance to a copper plate collector whose aperture area is approximately 33% smaller. Another options for providing freeze protection to an SDHW system is to turn it off during the winter. Choosing a three-season operating period means two things. First, the system will have different optimums such as slope and collector area. Second, the wintertime solar energy incident on the collector is unavailable for meeting a heating load. However, the system`s heat exchanger becomes unnecessary and removing it increases the amount of energy that arrives at the storage tank during those periods in which the system is operating.

Bradley, D.E.

1997-12-31

58

Comparison Between TRNSYS Software Simulation and F-Chart Program on Solar Domestic Hot Water System  

E-print Network

This study presents the accuracy test of a TRNSYS Solar Domestic Hot Water (SDHW) System simulation. The testing is based on comparing the results with the F-Chart software. The selected system to carry out the tests was the Active Solar Domestic...

Haberl, J. S.; Baltazar, J. C.; Mao, C.

2012-01-01

59

Domestic wash water reclamation for reuse as commode water supply using filtration: Reverse-osmosis separation technique  

NASA Technical Reports Server (NTRS)

A combined filtration-reverse-osmosis water recovery system has been evaluated to determine its capability to reclaim domestic wash water for reuse as a commode water supply. The system produced water that met all chemical and physical requirements established by the U.S. Public Health Service for drinking water with the exception of carbon chloroform extractables, methylene blue active substances, and phenols. It is thought that this water is of sufficient quality to be reused as commode supply water. The feasibility of using a combined filtration and reverse-osmosis technique for reclaiming domestic wash water has been established. The use of such a technique for wash-water recovery will require a maintenance filter to remove solid materials including those less than 1 micron in size from the wash water. The reverse-osmosis module, if sufficiently protected from plugging, is an attractive low-energy technique for removing contaminants from domestic wash water.

Hall, J. B., Jr.; Batten, C. E.; Wilkins, J. R.

1974-01-01

60

Dispersal of fine sediment in nearshore coastal waters  

USGS Publications Warehouse

Fine sediment (silt and clay) plays an important role in the physical, ecological, and environmental conditions of coastal systems, yet little is known about the dispersal and fate of fine sediment across coastal margin settings outside of river mouths. Here I provide simple physical scaling and detailed monitoring of a beach nourishment project near Imperial Beach, California, with a high portion of fines (40% silt and clay by weight). These results provide insights into the pathways and residence times of fine sediment transport across a wave-dominated coastal margin. Monitoring of the project used physical, optical, acoustic, and remote sensing techniques to track the fine portion of the nourishment sediment. The initial transport of fine sediment from the beach was influenced strongly by longshore currents of the surf zone that were established in response to the approach angles of the waves. The mean residence time of fine sediment in the surf zone—once it was suspended—was approximately 1 hour, and rapid decreases in surf zone fine sediment concentrations along the beach resulted from mixing and offshore transport in turbid rip heads. For example, during a day with oblique wave directions and surf zone longshore currents of approximately 25 cm/s, the offshore losses of fine sediment in rips resulted in a 95% reduction in alongshore surf zone fine sediment flux within 1 km of the nourishment site. However, because of the direct placement of nourishment sediment on the beach, fine suspended-sediment concentrations in the swash zone remained elevated for several days after nourishment, while fine sediment was winnowed from the beach. Once offshore of the surf zone, fine sediment settled downward in the water column and was observed to transport along and across the inner shelf. Vertically sheared currents influenced the directions and rates of fine sediment transport on the shelf. Sedimentation of fine sediment was greatest on the seafloor directly offshore of the nourishment site. However, a mass balance of sediment suggests that the majority of the fine sediment moved far away (over 2 km) from the nourishment site or to water depths greater than 10 m, where fine sediment represents a substantial portion of the bed material. Thus, the fate of fine sediment in nearshore waters was influenced strongly by wave conditions, surf zone and rip current transport, and the vertical density and flow conditions of coastal waters.

Warrick, Jonathan A.

2013-01-01

61

Influence of wave and current flow on sediment-carrying capacity and sediment flux at the water-sediment interface.  

PubMed

In nearshore waters, spatial and temporal scales of waves, tidal currents, and circulation patterns vary greatly. It is, therefore, difficult to combine these factors' effects when trying to predict sediment transport processes. This paper proposes the concept of significant wave velocity, which combines the effects of waves, tides, and ocean currents using the horizontal kinetic energy superposition principle. Through a comparison of the relationship between shear stress at the water-sediment interface and sediment-carrying capacity, assuming equilibrium sediment flux, a new formula for sediment-carrying capacity, which incorporates the concept of significant wave velocities, is derived. Sediment-carrying capacity is a function of the critical velocity, which increases with water depth and decreases with increasing relative roughness of the sea bed. Finally, data from field observation stations and simulations are used to test the proposed formula. The results show that the new formula is in good agreement with both field and simulation data. This new formula for sediment-carrying capacity can be used to simulate nearshore sediment transport. PMID:25259499

Zheng, Jun; Li, Ruijie; Yu, Yonghai; Suo, Anning

2014-01-01

62

Sediment monitoring and the European Water Framework Directive.  

PubMed

Sediment is an essential, integral and dynamic part of our river basins. A healthy river needs sediment as a source of life. Unfortunately, sediment also acts as a potential sink for many hazardous chemicals. Above a certain level of contamination this will result in negative impacts such a loss of biodiversity. This is deemed intolerable by society and hence the European Water Framework Directive (WFD) was developed. The WFD aims to achieve a good status of all European waters by the year 2015. The WFD does not specifically deal with sediment although it is clear that there is a link between sediment quality and achieving of this WFD objective. However, related to sediment monitoring there are some direct links in the WFD, which are further explained in this paper. PMID:18946159

Brils, Jos

2008-01-01

63

Recent sediment dynamics in the region of Mekong water influence  

NASA Astrophysics Data System (ADS)

The recent fine sediment dynamics in the region of fresh water influence (ROFI) off the Mekong River are subject of this study. Each year about 160 t of sediment discharges from the river and disperses over the shelf. The typical tropical monsoon regime induces the pronounced seasonal cycle of the discharge of water and sediment. This cycle is reflected in rates of erosion and deposition on the shelf. The modern hypothesis says that this cycle of sediment results in deposition of sediment on the shelf during the high flow season and the transport back into the river mouth during the low flow season. A coupled hydrodynamic-wind-wave and sediment model, which simulates the seasonal cycle of the system, is used to prove this hypothesis.

Hein, Hartmut; Hein, Birte; Pohlmann, Thomas

2013-11-01

64

Subcritical water extraction of polychlorinated biphenyls from soil and sediment  

Microsoft Academic Search

Two certified reference materials, an industrial soil (CRM 481) and a river sediment (NIST 1939), were extracted by subcritical water at 50 atm and temperatures ranging from 50 to 300°C. The extraction efficiency of PCBs is extremely dependent on water temperature, since the polarity (dielectric constant) of water can be dramatically lowered by raising the water temperature. While only traces

Yu. Yang; S. Bewadt; Steven B. Hawthorne; David J. Miller

1995-01-01

65

Microbiological Evaluation of Water Quality from Urban Watersheds for Domestic Water Supply Improvement  

PubMed Central

Agricultural and urban runoffs may be major sources of pollution of water bodies and major sources of bacteria affecting the quality of drinking water. Of the different pathways by which bacterial pathogens can enter drinking water, this one has received little attention to date; that is, because soils are often considered to be near perfect filters for the transport of bacterial pathogens through the subsoil to groundwater. The goals of this study were to determine the distribution, diversity, and antimicrobial resistance of pathogenic Escherichia coli isolates from low flowing river water and sediment with inputs from different sources before water is discharged into ground water and to compare microbial contamination in water and sediment at different sampling sites. Water and sediment samples were collected from 19 locations throughout the watershed for the isolation of pathogenic E. coli. Heterotrophic plate counts and E. coli were also determined after running tertiary treated water through two tanks containing aquifer sand material. Presumptive pathogenic E. coli isolates were obtained and characterized for virulent factors and antimicrobial resistance. None of the isolates was confirmed as Shiga toxin E. coli (STEC), but as others, such as enterotoxigenic E. coli (ETEC). Pulsed field gel electrophoresis (PFGE) was used to show the diversity E. coli populations from different sources throughout the watershed. Seventy six percent of the isolates from urban sources exhibited resistance to more than one antimicrobial agent. A subsequent filtration experiment after water has gone through filtration tanks containing aquifer sand material showed that there was a 1 to 2 log reduction in E. coli in aquifer sand tank. Our data showed multiple strains of E. coli without virulence attributes, but with high distribution of resistant phenotypes. Therefore, the occurrence of E. coli with multiple resistances in the environment is a matter of great concern due to possible transfer of resistant genes from nonpathogenic to pathogenic strains that may result in increased duration and severity of morbidity. PMID:22408583

Ibekwe, A. Mark; Murinda, Shelton E.; Graves, Alexandria K.

2011-01-01

66

DISTRIBUTION OF ORGANIC WASTEWATER CONTAMINANTS BETWEEN WATER AND SEDIMENT IN SURFACE WATERS OF THE UNITED STATES  

EPA Science Inventory

Trace concentrations of pharmaceuticals and other organic wastewater contaminants have been determined in the surface waters of Europe and the United States. A preliminary report of substantially higher concentrations of pharmaceuticals in sediment suggests that bottom sediment ...

67

Sediment pore water distribution coefficients of PCB congeners in enriched black carbon sediment  

PubMed Central

More than 2300 sediment pore water distribution coefficients (KPCBi ds) of 93 polychlorinated biphenyls (PCBs) were measured and modeled from sediments from Indiana Harbor and Ship Canal. KPCBi ds were calculated from previously reported bulk sediment values and newly analyzed pore water. PCBs in pore waters were measured using SPME PDMS-fiber and ?PCB ranged from 41 to 1500 ng L?1. The resulting KPCBi ds were ~ 1 log unit lower in comparison to other reported values. A simple model for the KPCBi d consisted of the product of the organic carbon fraction and the octanol-water partition coefficient and provided an excellent prediction for the measured values, with a mean square error of 0.09 ± 0.06. Although black carbon content is very high in these sediments and was expected to play an important role in the distribution of PCBs, no improvement was obtained when a two-carbon model was used. PMID:23974165

MARTINEZ, ANDRES; O'SULLIVAN, COLIN; REIBLE, DANNY; HORNBUCKLE, KERI C.

2013-01-01

68

Comparing Sediment and Pore-water Measurements as Predictors of PCB Uptake by Oligochaetes from Sediments  

EPA Science Inventory

There is an increasing amount of chemical and biological evidence that using sediment concentrations and commonly applied Koc values frequently overpredicts interstitial water concentrations of HOCs, and thereby overestimates uptake and/or effects of those chemicals on exposed or...

69

Sediment pore water distribution coefficients of PCB congeners in enriched black carbon sediment.  

PubMed

More than 2300 sediment pore water distribution coefficients (KPCBi ds) of 93 polychlorinated biphenyls (PCBs) were measured and modeled from sediments from Indiana Harbor and Ship Canal. KPCBi ds were calculated from previously reported bulk sediment values and newly analyzed pore water. PCBs in pore waters were measured using SPME PDMS-fiber and ?PCB ranged from 41 to 1500 ng L(-1). The resulting KPCBi ds were ~1 log unit lower in comparison to other reported values. A simple model for the KPCBi d consisted of the product of the organic carbon fraction and the octanol-water partition coefficient and provided an excellent prediction for the measured values, with a mean square error of 0.09 ± 0.06. Although black carbon content is very high in these sediments and was expected to play an important role in the distribution of PCBs, no improvement was obtained when a two-carbon model was used. PMID:23974165

Martinez, Andres; O'Sullivan, Colin; Reible, Danny; Hornbuckle, Keri C

2013-11-01

70

Water and Sediment Quality in the Yukon River Basin, Alaska, During Water Year 2005  

E-print Network

Water and Sediment Quality in the Yukon River Basin, Alaska, During Water Year 2005 Open.S. Geological Survey scientists measuring discharge at the mouth of the Forty-mile River in Yukon Territories, Canada, August 2004 #12;Water and Sediment Quality in the Yukon River Basin, Alaska, During Water Year

71

Bio-toxicological assays to test water and sediment quality  

Microsoft Academic Search

This study assessed the bio-toxicological assays efficacy in the control of effluent waters deriving from purification plants, such as industrial or wastewater discharge and marine sediment collected from the Adriatic sea on the Italian Coast. The analysis was performed using either Acute Toxicity Test containing bioluminescent bacteria or Algal Growth Inhibitory Test (used on sediments only). Furthermore, samples were also

Rossella Grande; Stefania Di Pietro; Emanuela Di Campli; Soraya Di Bartolomeo; Barbara Filareto; Luigina Cellini

2007-01-01

72

Flow of water and sediments through Southwestern riparian systems  

E-print Network

Flow of water and sediments through Southwestern riparian systems Leonard F. Peter F. and Kenneth N. Abstract.-The paper describes streamflow, sediment movement and veg- etation interactions within riparian systems of the southwestern United States. Riparian systems are found in a wide range of vegetation types

73

Toxicity of silicon carbide nanowires to sediment-dwelling invertebrates in water or sediment exposures  

USGS Publications Warehouse

Silicon carbide nanowires (SiCNW) are insoluble in water. When released into an aquatic environment, SiCNW would likely accumulate in sediment. The objective of this study was to assess the toxicity of SiCNW to four freshwater sediment-dwelling organisms: amphipods (Hyalella azteca), midges (Chironomus dilutus), oligochaetes (Lumbriculus variegatus), and mussels (Lampsilis siliquoidea). Amphipods were exposed to either sonicated or nonsonicated SiCNW in water (1.0 g/L) for 48 h. Midges, mussels, and oligochaetes were exposed only to sonicated SiCNW in water for 96 h. In addition, amphipods were exposed to sonicated SiCNW in whole sediment for 10 d (44% SiCNW on dry wt basis). Mean 48-h survival of amphipods exposed to nonsonicated SiCNW in water was not significantly different from the control, whereas mean survival of amphipods exposed to sonicated SiCNW in two 48-h exposures (0 or 15% survival) was significantly different from the control (90 or 98% survival). In contrast, no effect of sonicated SiCNW was observed on survival of midges, mussels, or oligochaetes. Survival of amphipods was not significantly reduced in 10-d exposures to sonicated SiCNW either mixed in the sediment or layered on the sediment surface. However, significant reduction in amphipod biomass was observed with the SiCNW either mixed in sediment or layered on the sediment surface, and the reduction was more pronounced for SiCNW layered on the sediment. These results indicated that, under the experimental conditions, nonsonicated SiCNW in water were not acutely toxic to amphipods, sonicated SiCNW in water were acutely toxic to the amphipods, but not to other organisms tested, and sonicated SiCNW in sediment affected the growth but not the survival of amphipods.

Mwangi, Joseph N.; Wang, Ning; Ritts, Andrew; Kunz, James L.; Ingersoll, Christopher G.; Li, Hao; Deng, Baolin

2011-01-01

74

Toxicity and genotoxicity of water and sediment from streams on dotted duckweed (Landoltia punctata).  

PubMed

Most rivers are used as a source to supply entire cities; the quality of water is directly related to the quality of tributaries. Unfortunately men have neglected the importance of streams, which receive domestic and industrial effluents and transport nutrients and pesticides from rural areas. Given the complexity of the mixtures discharged into these water bodies, this study aimed to evaluate the quality of water and sediment of ten tributaries of Pirapó River, in Maringá, Paraná State, Brazil. To this end, the free-floating macrophyte Landoltia punctata (G. Meyer) Les & D.J.Crawford was used as test organism in microcosm, and the toxicity of water and sediment samples was evaluated by the relative growth rate, dry/fresh biomass ratio, and genotoxic effects (comet assay). Samples of water and sediment of each stream were arranged in microcosms with L. punctata. Seven days later, plants were collected for analysis. Nutrient levels were higher than the reference location, indicating eutrophication, but the results indicated a toxic effect for only three streams, and a genotoxic effect for all streams. PMID:25627585

Factori, R; Leles, Sm; Novakowski, Gc; Rocha, Clsc; Thomaz, Sm

2014-11-01

75

Water recovery and solid waste processing for aerospace and domestic applications  

NASA Technical Reports Server (NTRS)

The work is described accomplished in compiling information needed to establish the current water supply and waste water processing requirements for dwellings, and for developing a preliminary design for a waste water to potable water management system. Data generated was used in formulation of design criteria for the preliminary design of the waste water to potable water recycling system. The system as defined was sized for a group of 500 dwelling units. Study tasks summarized include: water consumption, nature of domestic water, consumer appliances for low water consumption, water quality monitoring, baseline concept, and current and projected costs.

Murawczyk, C.

1973-01-01

76

Sediment and toxic contaminant transport modeling in coastal waters  

SciTech Connect

A hydrodynamic model, CAFE-I, a wave refraction model, LO3D, and a sediment and contaminant transport model, FETRA, were selected as tools for evaluating exposure levels of radionuclides, heavy metals, and other toxic chemicals in coastal waters. Prior to the application of these models to the Irish Sea and other coastal waters, the finite element model, FETRA, was tested to demonstrate its ability to simulate sediment and contaminant interactions (e.g., adsorption and desorption), and the mechanisms governing the transport, deposition, and resuspension of contaminated sediments.

Onishi, Y.; Mayer, D.W.; Argo, R.S.

1982-02-01

77

Mid frequency shallow water fine-grained sediment attenuation measurements.  

PubMed

Attenuation is perhaps the most difficult sediment acoustic property to measure, but arguably one of the most important for predicting passive and active sonar performance. Measurement techniques can be separated into "direct" measurements (e.g., via sediment probes, sediment cores, and laboratory studies on "ideal" sediments) which are typically at high frequencies, O(10(4)-10(5)) Hz, and "indirect" measurements where attenuation is inferred from long-range propagation or reflection data, generally O(10(2)-10(3)) Hz. A frequency gap in measurements exists in the 600-4000?Hz band and also a general acknowledgement that much of the historical measurements on fine-grained sediments have been biased due to a non-negligible silt and sand component. A shallow water measurement technique using long range reverberation is critically explored. An approximate solution derived using energy flux theory shows that the reverberation is very sensitive to depth-integrated attenuation in a fine-grained sediment layer and separable from most other unknown geoacoustic parameters. Simulation using Bayesian methods confirms the theory. Reverberation measurements across a 10?m fine-grained sediment layer yield an attenuation of 0.009?dB/m/kHz with 95% confidence bounds of 0.006-0.013?dB/m/kHz. This is among the lowest values for sediment attenuation reported in shallow water. PMID:23862792

Holland, Charles W; Dosso, Stan E

2013-07-01

78

Measure Guideline: Combination Forced-Air Space and Tankless Domestic Hot Water Heating Systems  

SciTech Connect

This document describes design and application guidance for combination space and tankless domestic hot water heating systems (combination systems) used in residential buildings, based on field evaluation, testing, and industry meetings conducted by Building Science Corporation. As residential building enclosure improvements continue to drive heating loads down, using the same water heating equipment for both space heating and domestic water heating becomes attractive from an initial cost and space-saving perspective. This topic is applicable to single- and multi-family residential buildings, both new and retrofitted.

Rudd, A.

2012-08-01

79

Microbial quality of domestic and imported brands of bottled water in Trinidad  

Microsoft Academic Search

A cross-sectional study was conducted to determine the microbial quality of domestic and imported brands of bottled water available in Trinidad, purchased from six geographical regions in Trinidad, and representing the whole island. A sample size of 344 bottles of water was determined by using a precision rate of 2% and a Type 1 error of 5%. The membrane filter

J. Bharath; M. Mosodeen; S. Motilal; S. Sandy; S. Sharma; T. Tessaro; K. Thomas; M. Umamaheswaran; D. Simeon; A. A. Adesiyun

2003-01-01

80

Development of Standardized Domestic Hot Water Event Schedules for Residential Buildings  

SciTech Connect

The Building America Research Benchmark is a standard house definition created as a point of reference for tracking progress toward multi-year energy savings targets. As part of its development, the National Renewable Energy Laboratory has established a set of domestic hot water events to be used in conjunction with sub-hourly analysis of advanced hot water systems.

Hendron, R.; Burch, J.

2008-08-01

81

Antifouling biocides in water and sediments from California marinas.  

PubMed

Irgarol 1051 is a common antifouling biocide and is highly toxic to non-target plant species at low ng/L concentrations. We measured up to 254 ng/L Irgarol in water and up to 9 ng/g dry weight Irgarol in sediments from Southern California recreational marinas. Irgarol's metabolite, M1, concentrations were up to 62 ng/L in water and 5 ng/g dry weight in sediments. Another antifouling biocide, diuron, reached up to 68 ng/L in water and 4 ng/g dry weight in sediments. The maximum Irgarol concentrations in water were greater than the Irgarol concentration recommended as the plant toxicity benchmark (136 ng/L), suggesting that Irgarol concentrations may be high enough to cause changes in phytoplankton communities in the sampled marinas. Irgarol concentrations measured in sediments were greater than calculated Environmental Risk Limits (ERLs) for Irgarol in sediments (1.4 ng/g). Antifouling pesticide accumulation in sediments may present a potential undetermined risk for benthic organisms. PMID:23453818

Sapozhnikova, Yelena; Wirth, Edward; Schiff, Kenneth; Fulton, Michael

2013-04-15

82

Analysis of mitochondrial D-loop region casts new light on domestic water buffalo ( Bubalus bubalis) phylogeny  

Microsoft Academic Search

The phylogeny of water buffaloes (Bubalus bubalis) is still a matter of discussion, especially if the two types of domestic water buffalo (swamp and river) derived from different domestication events or if they are products of human selection. To obtain more insight, we analyzed the entire mitochondrial D-loop region of 80 water buffaloes of four different breeds, i.e., 19 swamp

Gerold Kierstein; Marcelo Vallinoto; Artur Silva; Maria Paula Schneider; Leopoldo Iannuzzi; Bertram Brenig

2004-01-01

83

SURVEY OF CONTAMINANTS IN FRASER RIVER SUSPENDED SEDIMENT AND WATER  

E-print Network

and inorganic contaminants were measured in time-integrated samples of suspended sediment and water of the initial dilution zone (IDZ), in the Main Arm. Most of the parameters measured were well below the federal water quality guidelines, provincial criteria, or regional objectives. Total polychlorinated biphenyls

84

Nitrogen cycling in different types of sediments from Danish waters  

Microsoft Academic Search

Variations in sediment N:C ratios were correlated with water depth and season. ¹⁴NHâ\\/sup +\\/ was used to measure the rates of NHâ\\/sup +\\/ production (d) and incorporation into bacterial cells (i) in sediments from different stations, at different seasons. The validity of the rates d and i was indicated by the predicted correlation of d:i ratios with N:C ratios of

T. H. Blackburn; K. Henridsen

1983-01-01

85

An evaluation of rural communities’ water use patterns and preparedness to manage domestic water sources in Zimbabwe  

NASA Astrophysics Data System (ADS)

This paper makes an evaluation of rural communities’ preparedness to manage domestic water sources in Zimbabwe, as a way of assessing rural people’s willingness to contribute in cash and kind to safe and clean domestic water. A questionnaire was administered to respondents in two areas that have different rainfall regimes, as water availability was hypothesised to affect its management. This was complemented by interviews with personnel from government and semi-government institutions involved in provision of domestic water in rural areas. Information gathered included respondents’ awareness of the water resource ownership and supply structure at the community and national level, roles played by various institutions in domestic water provision, water sources ownership, number and distribution of water points, water use patterns, water based socio-economic activities and respondents’ willingness to contribute towards establishment, operation and maintenance of water points. Respondents attributed water ownership to God, the government, the community, ancestors, chiefs, ZINWA, RDCS and no one. Boreholes, shallow and deep wells, rivers, dams, canals and taps were mainly used for primary water uses like drinking, cooking, bathing, livestock watering, gardening and laundry. Brick making, gardening and irrigating plots were classified as commercial water uses because they were used to generate income. Views on water ownership affected perceptions towards establishment, maintenance and management of water points. There was a higher preference for community than individual participation except for canals and taps. The responsibility for water point establishment and repairs were regarded as the responsibility of the government, community and donors. Respondents without piped water had higher WTP amounts for the repair and desiltation of water points than those with piped water. This showed a willingness to ensure that the working order of water points was assured. Frequent maintenance and timely repairs of community-managed schemes showed respondents’ willingness and preparedness to contribute towards maintenance of their water points. It can be concluded that people are willing to participate in the management of domestic water sources. However, limited capacity to finance establishment of water points was a problem.

Machingambi, Memory; Manzungu, Emmanuel

86

Solar heating and domestic hot water system installed at North Dallas High School. Final report  

SciTech Connect

This Document is the Final Technical Report of the Solar Energy System located at the North Dallas High School, Dallas, Texas. The system is designed as a retrofit in a three story with basement, concrete frame high school building. The building was air conditioned with an electric drive 300-ton chilled water central system in 1973. The building contains 126,000 square feet and the solar energy system will preheat 100 percent of domestic hot water and supply 47.5 percent of annual building heating requirements. During the building cooling seasons, the solar energy system will supply 100 percent of domestic hot water. The solar energy system consists of 4800 square feet (320 panels) Lennox/Honeywell flat plate liquid collector subsystem, and a 10,000 gallon steel tank storage subsystem circulating hot water producing 686.6 x 10/sup 6/ Btu/year (specified) building heating and domestic hot water heating. The start up date is December 4, 1979. Extracts from the site files, specification references for solar modification to existing building heating and domestic hot water systems, drawings, installation, operation and maintenance instructions are presented.

Not Available

1980-05-01

87

Brackish water treatment using desalinating device for domestic purpose  

Microsoft Academic Search

The cheapest and also the most unsophisticated way to attain potable water from the brackish water normally available at the taps is reverse osmosis process. Today there is strong need for appropriately treated wastewater to protect the environment and to ensure that freshwater is available for all applications. Semi permeable membranes allow the passage of water or other small molecules

Savita Dixit; Prashant Baredarb; G. Dixit

2009-01-01

88

Technical evaluation of a small-scale reverse osmosis desalination unit for domestic water  

Microsoft Academic Search

Tunisian standards for drinking water tolerate a maximum Total Dissolved Salts (TDS) of 1.5 g\\/L. The domestic water presents usually a salinity greater than 0.5 g\\/L. In the last few years, several small capacity reverse osmosis desalination prototypes have been marketed. They are used to desalinate brackish water with TDS lower than 1.5 g\\/L. The performances of such type of

H. Elfil; A. Hamed; A. Hannachi

2007-01-01

89

Water recovery and solid waste processing for aerospace and domestic applications. Volume 1: Final report  

NASA Technical Reports Server (NTRS)

A comprehensive study of advanced water recovery and solid waste processing techniques employed in both aerospace and domestic or commercial applications is reported. A systems approach was used to synthesize a prototype system design of an advanced water treatment/waste processing system. Household water use characteristics were studied and modified through the use of low water use devices and a limited amount of water reuse. This modified household system was then used as a baseline system for development of several water treatment waste processing systems employing advanced techniques. A hybrid of these systems was next developed and a preliminary design was generated to define system and hardware functions.

Murray, R. W.

1973-01-01

90

Meeting of the Waters A Comparison of Suspended Sediment and Discharge of the  

E-print Network

Meeting of the Waters A Comparison of Suspended Sediment and Discharge of the Illecillewaet River..................................................................................................................................... 23 Comparison of Sediment Load during Clear Weather and Storm Weather.............................. 23 Differences/Similarities in Suspended Sediment Load of Illecillewaet River and Asulkan Brook

Smith, Dan

91

A model for sulfur accumulation in soft water lake sediments  

SciTech Connect

A geochemical model for sulfur in soft water lake sediments of the Adirondack Mountains, New York, is developed to gain insight into the timing and magnitude of historical changes in sulfur loading. Surficial sulfur concentrations range from 3500 to 10,000 {mu}g g{minus}{sup 1}, increase to 6000 to >20,000 {mu}g g{minus}{sup 1} at a depth of 2-6 cm, and then decrease downcore to background levels of 2500-7500 {mu}g g{minus}{sup 1}. Sulfate concentrations are about 50-80 {mu}M in the overlying water and decrease rapidly below the sediment-water interface. A mathematical model is constructed assuming sulfur is incorporated into sediments by burial of detrital organic matter and by diffusion of dissolved sulfate from the overlying water with subsequent fixation into the sediment solids. Several scenarios of historical sulfate deposition were examined as model boundary conditions. The observed sediment sulfur profiles are best modeled using boundary conditions showing loading increases of about a factor of 8 since about 1940. Assuming as much as a decade of retention of sulfate within the terrestrial portion of the ecosystem, this suggests that significant increases in sulfate deposition rates began sometime about 1930 in this area. 34 refs., 7 figs., 2 tabs.

Matisoff, G. [Case Western Reserve Univ., Cleveland, OH (United States)] [Case Western Reserve Univ., Cleveland, OH (United States); Holdren, G.R. Jr. [Battelle Pacific Northwest Labs., Richland, WA (United States)] [Battelle Pacific Northwest Labs., Richland, WA (United States)

1995-07-01

92

Spectroscopic analyses of pollutants in water, sediment and fish  

NASA Astrophysics Data System (ADS)

Water ways in Egypt is suffering from continual discharge without adequate treatment especially in the Delta and greater Cairo area. Accordingly water, sediments and catfishes were collected from El Mouheet El Youmna drain in Giza. Cd, Cr, Pb and Zn were determined furthermore the molecular structure of sediment and catfish were conducted with FTIR spectroscopy. Although studied metals were lower in water, higher values are recorded in sediment and catfish samples. FTIR shows possible interaction among metals and organic structures mainly proteins. The bioaccumulation of Pb and Cd proportion was significantly increased in the liver tissues of catfish. A correlation coefficient among sediment and fish liver metals accumulation exist. This infers that the waste assimilation capacity for the drain is high, a phenomena that could be ascribed to dilution, sedimentation and continual water exchange. Furthermore, the genotoxicity affect in catfish genomic corroborates the genus diagnostic markers which attributed to long pollution. This is an indication that agriculture and industrial wastes discharged into the drain has badly a significant effect on the ecological balance.

Abdel-Gawad, Fagr Kh.; Ibrahim, Hanan S.; Ammar, Nabila S.; Ibrahim, Medhat

2012-11-01

93

Solar heating, cooling and domestic hot water system installed at Columbia Gas System Service Corporation, Columbus, Ohio  

NASA Technical Reports Server (NTRS)

The solar energy system installed in the building has 2,978 sq ft of single axis tracking, concentrating collectors and provides solar energy for space heating, space cooling and domestic hot water. A 1,200,000 Btu/hour water tube gas boiler provides hot water for space heating. Space cooling is provided by a 100 ton hot water fired absorption chiller. Domestic hot water heating is provided by a 50 gallon natural gas domestic storage water heater. Extracts from the site files, specification references, drawings, installation, operation and maintenance instructions are included.

1980-01-01

94

Estimate of self-supplied domestic water use in Nebraska during 1980  

USGS Publications Warehouse

No data base of actual measurements exists for self-supplied, domestic water use in Nebraska, because Nebraska laws do not require drilling permits, well registration, or reporting of volumes withdrawn from domestic wells. Self-supplied, domestic water use of 31,280 acre-ft in Nebraska during 1980 was computed from estimates of gal/day/capita use for each county. This represents an average of 95 gal/day/capita. During 1980, county use volumes ranged from 30 acre-ft in Hooker and Pawnee Counties to 1,380 acre-ft in Douglas County, and Hydrologic Unit use volumes ranged from < 5 acre-ft to 2,270 acre-ft. Natural Resources Districts ' (NRD) use volumes ranged from 360 acre-ft in Middle Niobrara NRD to 3,530 acre-feet in the Lower Elkhorn NRD for the same period. (Author 's abstract)

Steele, E.K.

1985-01-01

95

Interdependent infrastructure modelling: Intergration of domestic water models  

Microsoft Academic Search

In order to assess the viability of using EPAnet source code and the time domain Infrastructure Interdependencies Simulator (I2Sim) for predictive modeling, a critical failure of a municipal water supply was modeled on a university campus. During winter operations, a campus steam plant experienced a failure in operations due in part from an unobserved anomaly in the municipal water supply.

Adam Shypanski; Viet-Ha Pham; Americo Cunha; Ernest Yanful

2011-01-01

96

Opportunities for utility involvement with solar domestic hot water  

Microsoft Academic Search

Solar water heating is one of a number of options that can be considered under utility demand-side management (DSM) programs. Utilities perceive a range of potential benefits for solar water heating in terms of customer service, energy conservation, load management, environmental enhancement, and public relations. The solar industry may benefit from utility marketing efforts, economies of scale, added credibility, financing

N. Carlisle; C. Christensen; L. Barrett

1992-01-01

97

Bacterial Mercury Methylation At The Sediment-Water Interface Of Mercury Contaminated Sediments  

EPA Science Inventory

Bench scale experiments were conducted to improve our understanding of bacterial mediation of mercury transformation (methylation), specifically those factors which govern the production of methyl mercury (MeHg) at the sediment-water interface. The greatest cause for concern re...

98

Study of water evaporation and condensation in a domestic refrigerator loaded by wet product  

Microsoft Academic Search

This study was carried out to gain a better insight into evaporation and condensation phenomena due to natural convection in a domestic refrigerator. An experiment was undertaken in a refrigerator loaded with 40humid plaster cylinders (50mm diameter). The weight variation of the cylinders was followed over 12days and the rate of water evaporation (or condensation for some cylinders) was calculated.

O. Laguerre; S. Benamara; D. Flick

2010-01-01

99

Commissioning the Domestic Hot Water System on a Large University Campus: A Case Study  

E-print Network

The Texas A&M University (TAMU) main campus in College Station consists of 110 buildings with 12.5 million square feet of gross building space. Seventy-one of these buildings are connected to the main campus domestic hot water (DHW) distribution...

Chen, H.; Bensouda, N.; Claridge, D.; Bruner, H.

2004-01-01

100

Solar heating and domestic hot water system installed at North Dallas High School  

NASA Technical Reports Server (NTRS)

The solar energy system located at the North Dallas High School, Dallas, Texas is discussed. The system is designed as a retrofit in a three story with basement, concrete frame high school building. Extracts from the site files, specification references for solar modification to existing building heating and domestic hot water systems, drawings, installation, operation and maintenance instructions are included.

1980-01-01

101

Procedures for Collecting and Processing Streambed Sediment and Pore Water for Analysis of Mercury as  

E-print Network

Procedures for Collecting and Processing Streambed Sediment and Pore Water for Analysis of Mercury Streambed Sediment and Pore Water for Analysis of Mercury as Part of the National Water-Quality Assessment for collecting and processing streambed sediment and pore water for analysis of mercury as part of the National

102

Advanced biological unit processes for domestic water recycling  

Microsoft Academic Search

Abstract The potential of advanced,biological unit operations for the recycling of grey and black waters has been evaluated. The membrane,bioreactor (MBR) demonstrated,the greatest efficacy towards water recycling in terms of all the quality determinants. Both the biologically aerated filter (BAF) and the MBR were able to effectively treat the organic and physical pollutants in all the types of wastewater,tested. The

B. jefferson; A. l. Laine; T. Stephenson; S. j. Judd

103

Water and Sediment Yields for Wala Dam Catchment Area  

NASA Astrophysics Data System (ADS)

Wala Watershed occupies the upper part of Al-Mujib Basin, Jordan, with Mediterranean climate, sparse inhabitants and moderate agriculture. The area, in spite of its limited water resources, is considered as an important water supply as it encompasses Al-Heidan springs and pumping wells, which supply Amman city with a considerable amount of water, it also includes Wala Dam that has been constructed for groundwater recharge purposes. Recognizing the threats of water and soil loss with the consequent sedimentation problems, and the benefits of watershed modeling techniques in studying such topics, this study comprised an application of the Soil and Water Assessment Tool (SWAT), associated with the Geographic Information System (GIS) to simulate the hydrology, soil erosion and sedimentation of Wala Dam Catchment Area. A set of hydrological techniques was utilized to simulate various components such as the Curve Number Method, the Rational Method and the Universal Soil Loss Equation (USLE) and modified USLE models. The use of such techniques in a GIS environment required certain types of data, which were collected and prepared either as database files such as the daily rainfall records, or as analytical GIS layers of soil, landuse/cover, drainage pattern and Digital Elevation Model (DEM). A weather generator was incorporated to generate any missed weather data. The area was discretized into 43 subbasins and 82 hydrologic response units. Two simulation series were performed using annual and monthly printout frequency. Several results were obtained including water and sediment yields at Wala Dam location with the respective delivery ratios, and spatial representation of precipitation, surface runoff, soil erosion, sediment and water yield on subbasin level. Model calibration and verification were carried out using flow rate and sediment yield data observed at Wala flow station and the results were satisfactory, indicating that this model can represent well the climatic and physical conditions of the area. Two prediction scenarios were performed, both indicated that the western and northern subbasins yield more water to the dam and are more susceptible to soil erosion and sediment generation. The study resulted in some recommendations to enhance the built model and suggest soil conservation and sediment reduction measures to control soil loss and maintain storage in Wala Dam reservoir, in addition to protecting its bottom against clogging through which the process of groundwater recharge might malfunction.

Tarawneh, E.

2009-04-01

104

Predicting water quality data in an unfilled reservoir using microcosm sediment-water simulation  

Microsoft Academic Search

The technique of microcosm sediment-water simulation was used to obtain predictive water quality data for the proposed Jordanelle Reservoir, Heber City, Utah. Sediment-water microcosms were prepared for four sites located in the north arm of the reservoir basin, including two sites located in an abandoned acid mine tailings pond. Data obtained from the tailings pond microcosms indicated that low pH

Douglas Craft

1985-01-01

105

Domestic water supply impacts by underground coal mining in Virginia, USA  

Microsoft Academic Search

Underground coal mining can affect wells and springs used as water supplies. In Virginia, concerns over such impacts are\\u000a felt by both surface owners and coal-mining firms. Virginia's geologic history has caused faults and fractures to be common\\u000a in its coalfield region, relative to other Appalachian coal-mining areas. The results of 73 investigations of alleged domestic\\u000a water supply impacts by

C. Zipper; W. Balfour; R. Roth; J. Randolph

1997-01-01

106

Bank Erosion, Mass Wasting, Water Clarity, Bathymetry and a Sediment  

E-print Network

Bank Erosion, Mass Wasting, Water Clarity, Bathymetry and a Sediment Budget Along the Dam this report. Suggested citation: Schenk, E.R., Hupp, C.R., Richter, J.M., and Kroes, D.E. 2010, Bank erosion...........................................................................................................................................................3 Bank Erosion

107

Solar domestic hot water system installed at Texas City, Texas  

NASA Technical Reports Server (NTRS)

This is the final technical report of the solar energy system located at LaQuinta Motor Inn, Texas City, Texas. The system was designed to supply 63 percent of the total hot water load for a new 98 unit motor inn. The solar energy system consists of a 2100 square feet Raypack liquid flat plate collector subsystem and a 2500 gallon storage subsystem circulating hot water producing 3.67 x 10 to the 8th power Btu/year. Abstracts from the site files, specification references, drawings, installation, operation, and maintenance instructions are included.

1980-01-01

108

Domestic Water Conservation Technologies: Federal Energy Management Program (FEMP) Federal Technology Alert (Booklet)  

SciTech Connect

Executive Order 13123 calls for the Federal government to conserve water as well as energy in its 500,000 facilities. To help set priorities among water-saving measures, the Federal Energy Management Program conducted a study of Federal water use in 1997. The study indicated that the government consumes more than 50% of its water in just three types of Federal facilities: housing, hospitals, and office buildings. These facilities have enough kitchens, rest rooms, and laundry areas to provide facility managers with many opportunities to begin reducing their water use (and utility costs) with appropriate water-saving fixtures and products. Therefore, this Federal Technology Alert focuses on domestic technologies, products, and appliances such as water-efficient faucets, showerheads, toilets, urinals, washing machines, and dishwashers. Conserving water also saves the energy needed to treat, pump, and heat that water in homes, businesses, and other buildings.

Not Available

2002-10-01

109

Extraction and concentration of phenolic compounds from water and sediment  

USGS Publications Warehouse

Continuous liquid-liquid extractors are used to concentrate phenols at the ??g l-1 level from water into dichloromethane; this is followed by Kuderna-Danish evaporative concentration and gas chromatography. The procedure requires 5 h for 18 l of sample water. Overall concentration factors around 1000 are obtained. Overall concentration efficiencies vary from 23.1 to 87.1%. Concentration efficiencies determined by a batch method suitable for sediments range from 18.9 to 73.8%. ?? 1980.

Goldberg, M.C.; Weiner, E.R.

1980-01-01

110

PRODUCTION OF DRINKING WATER FROM DOMESTIC WASTEWATER USING CAPILLARY NANOFILTRATION  

Microsoft Academic Search

Direct Capillary Nanofiltration (Direct CNF) is a new technique used for surface water and wastewater treatment in one step without pre-treatment. The CNF membrane module combines the favourable cleaning properties of capillary ultrafiltration membranes with the favourable separation properties of nanofiltration membranes in terms of removal of DOC, colour, bacteria, viruses and pesticides. Direct CNF was applied to Twente Canal

S. J. Tarek; S. Sayed

111

Sediment testing intermittent renewal system for the automated renewal of overlying water in toxicity tests with contaminated sediments  

SciTech Connect

A sediment testing intermittent renewal (STIR) system (stationary or portable) for invertebrate toxicity testing with contaminated sediments has been successfully developed and thoroughly tested at ERL-Duluth. Both the stationary and portable systems enable the maintenance of acceptable water quality (e.g. DO) through the capability of automatically renewing overlying water in sediment tests at rates ranging from 1 to 21 volume renewals/day. The STIR system not only significantly reduces the labor associated with renewal of overlying water but also affords a gentle exchange of water that results in virtually no sediment resuspension. Both systems can also be installed in a compact vented enclosure to permit safe testing of hazardous contaminated sediments. To date the STIR system has been used extensively for conducting 10-day bulk sediment tests with Chironomus tentans, Hyalella azteca and Lumbriculus variegatus.

Benoit, D.A.; Phipps, G.L.; Ankley, G.T.

1993-01-01

112

Mercury, Methylmercury, and Other Constituents in Sediment and Water from Seasonal and Permanent  

E-print Network

Mercury, Methylmercury, and Other Constituents in Sediment and Water from Seasonal and Permanent, the Sacramento River Watershed Program, and the United States Environmental Protection Agency Mercury A., 2009, Mercury, methylmercury, and other constituents in sediment and water from seasonal

113

FRAMEWORK FOR DEVELOPING SUSPENDED AND BEDDED SEDIMENT (SABS) WATER QUALITY CRITERIA  

EPA Science Inventory

EPA announces the release of the final document, Framework for Developing Suspended and Bedded Sediments (SABS) Water Quality Criteria which describes an integrative assessment process for developing water quality criteria suspended and bedded sediments in aquatic systems....

114

NEAR FIELD RECEIVING WATER MONITORING OF TRACE METALS IN CLAMS (MACOMA BALTHICA) AND SEDIMENTS  

E-print Network

NEAR FIELD RECEIVING WATER MONITORING OF TRACE METALS IN CLAMS (MACOMA BALTHICA) AND SEDIMENTS NEAR, CALIFORNIA #12;NEAR FIELD RECEIVING WATER MONITORING OF TRACE METALS IN CLAMS (MACOMA BALTHICA) AND SEDIMENTS....................................................................................................... 45 Appendix 2: Palo Alto Clams

115

Heavy metal pollution in water and sediments in the Kabini River, Karnataka, India.  

PubMed

The River Kabini in Karnataka, India carries natural and anthropogenic pollutants, mainly heavy metal concentrations of Cr, Cu, Fe, Mn, Ni, Pb and Zn which are released from industrial effluents, agricultural return flows and domestic sewage. Kabini, which is a tributary of the Cauvery, drains through the industrial area at Nanjangud, Karnataka, India. Heavy metals were determined in waters and sediment (2 ?m) of Kabini River. In the present investigation, chemical partitioning studies was carried out to know the association of base metals with various sedimentary phases. The concentrations of heavy metals are higher in loosely bonded fraction than the other studied fractions. Furthermore, the degree of sediment contamination was assessed by geochemical index. It should be pointed out that Cu and Cr show the highest pollution intensity. Cluster analysis was used to know about the inter correlation amongst the studied metals. It is evident that higher concentrations of metals are found in the vicinity of industrial effluents. The concentrations of Cr followed by Zn and Ni are rather higher than the maximum background values in the Kabini River sediment. This is especially true at the influx of paper mill effluents into the River. PMID:21213040

Taghinia Hejabi, Azadeh; Basavarajappa, H T; Karbassi, A R; Monavari, S M

2011-11-01

116

Sediment-water interactions and their effects upon water quality. (Latest citations from the NTIS bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning the testing and evaluation of fresh-water sediments. Citations discuss assessment and remediation of contaminated sediments, monitoring systems, sediment transport, water pollution effects, water traffic, habitats and fisheries, and the effect of dredging operation. National programs, acts, regulations, and criteria are examined. (Contains a minimum of 182 citations and includes a subject term index and title list.)

Not Available

1994-07-01

117

A longitudinal study of domestic water conservation behavior  

Microsoft Academic Search

A 1988 study of a school-linked sample in a metropolitan and a regional urban area established baseline data for knowledge, attitudes, intentions, and behavior with regard to water management and conservation (Murphy, Watson, & Moore, 1991). This paper reports on a 1991 follow-up, utilising both longitudinal and cross-sectional samples of students, teachers and parents, which aimed at identifying changes within

Susan Moore; Margot Murphy; Ray Watson

1994-01-01

118

Evaluation of petroleum-degrading potential of bacteria from water and sediment.  

PubMed Central

Bacteria from water and sediment of an oil-polluted harbor were examined for ability to degrade petroleum. Water samples contained a greater variety of bacterial species capable of degrading petroleum than sediment. Cultures from both water and sediment contained Pseudomonas and Acinetobacter spp. Bacteria present in the water samples produced significantly greater degradation of 2-,3-,4-, and 5-ring cycloalkanes and mono-, di-, tri-, tetra-, and pentaaromatics compared with bacteria in sediment samples. PMID:1211932

Walker, J D; Colwell, R R; Petrakis, L

1975-01-01

119

Ecotoxicological Assessment of Water and Sediment Pollution of the Iskar River bellow Samokov  

Microsoft Academic Search

A system of integral ecological indices has been worked out to assess the level of polution of water and sediments with hazardous substances. A model for the dynamics of the inegral index for water and sediments polution is proposed. This index was applied for ecotoxicological assessment of water and sediments polution of the Iskar river bellow Samokov. A modification method

Ivan Diadovski; Yana Raykovska; Niels De Pauw; Diederik Rousseau

120

Draix multidisciplinary observatory for water and sediment processes  

NASA Astrophysics Data System (ADS)

Over the last decades, much progress has been done in the modeling and conceptualizing of surface processes. Testing theories and models requires field data, and possibly long-term time series. Here we present a 30-year old field observatory dedicated to water and sediment fluxes in the French Alps. Draix observatory is located in a badland area of the French Alps (shale lithology), and includes several subcatchments which differ in size (0.001 to 1 km2) and vegetation coverage (bare soil or forest). Climate is mountainous and Mediterranean, characterized with summer storm-induced floods and winter frost. Data collected includes climatic data (rainfall, temperature) and water and sediment fluxes (discharge at the outlet of each subcatchment, suspended load and bedload fluxes). High frequency monitoring (minute/hour) is used to capture flood dynamics. Some soil hydraulic and geophysical properties, lidar scans and vegetation maps are also available. The combination of an erodible badland morphology and tough climatic conditions induces very high erosion rates and sediment yield (up to 70 tons/ha/yr). Observed erosion processes include landslides, small-scale debris flows, gully formation, weathering on the slopes and in the riverbeds, hyperconcentrated flows and in-transport sediment abrasion. The sediment response is highly non-linear with a strong seasonal pattern of storage and scour in the bed. Current research on Draix observatory is multidisciplinary and involves hydraulic engineers, hydrologists, geomorphologists, soil scientists and restoration ecologists. Fast rates of geomorphic changes, well-constrained sediment budgets and long data series are some of the advantages of this site for the study of earth surface processes. Our data is available for the community and we welcome everyone who is interested in collaborating on it.

Le Bouteiller, C.; Mathys, N.; Liébault, F.; Klotz, S.

2013-12-01

121

The influence of a variable volume water heater on the domestic load profile  

SciTech Connect

In this paper a variable volume water heater and a load impact model is presented. The variable volume water heater is a unique system that can be implemented as a residential demand-side management tool. The variable volume water heater can shift the electrical energy consumption, used to heat water, to off-peak time periods. The electrical energy is shifted without influencing the hot water usage of the customer. The load impact model simulates the effect of controlling the volume of stored hot water on a domestic load. The model mathematics as well as the model verification are discussed. The paper ends with a comparative case study on two residential areas. The case study indicates that the variable volume water heater can reduce the system peak as well as increase the off-peak energy consumption.

Lemmer, E.F.; Delport, G.J.

1999-12-01

122

Environmental assessment for the domestic water supply upgrades and consolidation on the Savannah River Site  

SciTech Connect

The domestic water systems on the Savannah River Site (SRS) are currently in need of upgrading to ensure compliance with the Safe Drinking Water Act and South Carolina Department of Health and Environmental Control (SCDHEC) Drinking Water Regulations. The SRS has 28 separate goundwater-based drinking water systems in use across the site. These aging systems were designed and constructed in the 1950s and are now facing increasing difficulties in meeting cur-rent regulations. Audits of the systems conducted by SCDHEC in 1986, 1988, 1991, and 1993 identified shortfalls in meeting the requirements for secondary maximum containment levels (MCLS) and SCDHEC design standards. Secondary MCLs are those items, such as odor or appearance, that do not pose a direct health impact. SRS has committed to SCDHEC to correct the drinking water discrepancies and construct two new consolidated inter-area drinking water systems. Upgrading the SRS drinking water systems would be necessary to support site activities regardless of the makeup or the mission at SRS. As such, the proposed upgrade and consolidation of SRS domestic water systems is treated as part of the ``No Action`` alternative for the Programmatic Environmental Impact Statement for Reconfiguration of the Nuclear Weapons Complex .

Not Available

1994-06-01

123

Remote Sensing of Suspended Sediments and Shallow Coastal Waters  

NASA Technical Reports Server (NTRS)

Ocean color sensors were designed mainly for remote sensing of chlorophyll concentrations over the clear open oceanic areas (case 1 water) using channels between 0.4 and 0.86 micrometers. The Moderate Resolution Imaging Spectroradiometer (MODIS) launched on the NASA Terra and Aqua Spacecrafts is equipped with narrow channels located within a wider wavelength range between 0.4 and 2.5 micrometers for a variety of remote sensing applications. The wide spectral range can provide improved capabilities for remote sensing of the more complex and turbid coastal waters (case 2 water) and for improved atmospheric corrections for Ocean scenes. In this article, we describe an empirical algorithm that uses this wide spectral range to identifying areas with suspended sediments in turbid waters and shallow waters with bottom reflections. The algorithm takes advantage of the strong water absorption at wavelengths longer than 1 micrometer that does not allow illumination of sediments in the water or a shallow ocean floor. MODIS data acquired over the east coast of China, west coast of Africa, Arabian Sea, Mississippi Delta, and west coast of Florida are used in this study.

Li, Rong-Rong; Kaufman, Yoram J.; Gao, Bo-Cai; Davis, Curtiss O.

2002-01-01

124

Solar heating and domestic hot water system installed at Kansas City, Fire Stations, Kansas City, Missouri  

NASA Technical Reports Server (NTRS)

The solar system was designed to provide 47 percent of the space heating, 8,800 square feet area and 75 percent of the domestic hot water (DHW) load. The solar system consists of 2,808 square feet of Solaron, model 2001, air, flat plate collector subsystem, a concrete box storage subsystem which contains 1,428 cubic feet of 0.5 inch diameter pebbles weighing 71.5 tons, a DHW preheat tank, blowers, pumps, heat exchangers, air ducting, controls and associated plumbing. Two 120 gallon electric DHW heaters supply domestic hot water which is preheated by the solar system. Auxiliary space heating is provided by three electric heat pumps with electric resistance heaters and four 30 kilowatt electric unit heaters. There are six modes of system operation.

1980-01-01

125

Integrated water and sediment flow simulation and forecasting models for river reaches  

NASA Astrophysics Data System (ADS)

SummaryIn the present study integrated water and sediment flow simulation and forecasting models for a river reach have been developed. The new models combine Muskingum model and the sediment rating model leading to integrated water discharge-sediment concentration model ( WSCM) and water discharge-sediment discharge model ( WSDM) for a reach. The models depict coherence in water discharge and sediment load variations at a site; incorporate two hydrologic variables, water discharge and sediment load for the gauge sites and represent revised forms of the basic Muskingum model. The models can be recast into forecasting form useful for obtaining downstream water and sediment flow forecasts ?t'=2kx time unit ahead. During calibration the models can select a commensurate inflow-outflow set depending on upstream and the downstream relative sediment discharge characteristics for a reach. The models can be used for developing Muskingum model for river reaches having no water discharge records. With forecasting capabilities the present models are useful in the real time management of sediment related pollution hazards in water courses. The study indicates that a single model could be used to describe both water and sediment flow in river reaches. The proposed model formulations are demonstrated for simulating and forecasting sediment concentration, sediment discharge and water discharge in the Mississippi River Basin, USA. Model parameters are estimated using non-dominated sorting Genetic Algorithm II (NSGA-II). Comparison of models performances with reported works show better performances by the present models.

Choudhury, Parthasarathi; Sil, Briti Sundar

2010-05-01

126

Sequestration of priority pollutant PAHs from sediment pore water employing semipermeable membrane devices  

Microsoft Academic Search

Semipermeable membrane devices (SPMDs) were employed to sample sediment pore water in static exposure studies under controlled laboratory conditions using (control pond and formulated) sediments fortified with 15 priority pollutant polycyclic aromatic hydrocarbons (PPPAHs). The sediment fortification level of 750 ng\\/g was selected on the basis of what might be detected in a sediment sample from a contaminated area. The

Kelly S Williamson; Jimmie D Petty; James N Huckins; Jon A Lebo; Edwin M Kaiser

2002-01-01

127

Numerical Simulation of Sediment-Associated Water Quality Processes for a Mississippi Delta Lake  

Technology Transfer Automated Retrieval System (TEKTRAN)

Three major sediment-associated processes were presented to describe the effects of sediment on lake water quality processes: the effect of suspended sediment on the light intensity for the growth of phytoplankton (PHYTO), the adsorption–desorption of nutrients by sediment, and the release of nutrie...

128

Can control of soil erosion mitigate water pollution by sediments?  

PubMed

The detrimental impact of sediment and associated pollutants on water quality is widely acknowledged, with many watercourses in the UK failing to meet the standard of 'good ecological status'. Catchment sediment budgets show that hill slope erosion processes can be significant sources of waterborne sediment, with rates of erosion likely to increase given predicted future weather patterns. However, linking on-site erosion rates with off-site impacts is complicated because of the limited data on soil erosion rates in the UK and the dynamic nature of the source-pathway-receptor continuum over space and time. Even so, soil erosion control measures are designed to reduce sediment production (source) and mobilisation/transport (pathway) on hill slopes, with consequent mitigation of pollution incidents in watercourses (receptors). The purpose of this paper is to review the scientific evidence of the effectiveness of erosion control measures used in the UK to reduce sediment loads of hill slope origin in watercourses. Although over 73 soil erosion mitigation measures have been identified from the literature, empirical data on erosion control effectiveness are limited. Baseline comparisons for the 18 measures where data do exist reveal erosion control effectiveness is highly variable over time and between study locations. Given the limitations of the evidence base in terms of geographical coverage and duration of monitoring, performance of the different measures cannot be extrapolated to other areas. This uncertainty in effectiveness has implications for implementing erosion/sediment risk reduction policies, where quantified targets are stipulated, as is the case in the EU Freshwater Fish and draft Soil Framework Directives. Also, demonstrating technical effectiveness of erosion control measures alone will not encourage uptake by land managers: quantifying the costs and benefits of adopting erosion mitigation is equally important, but these are uncertain and difficult to express in monetary terms. PMID:23815978

Rickson, R J

2014-01-15

129

A sediment resuspension and water quality model of Lake Okeechobee  

USGS Publications Warehouse

The influence of sediment resuspension on the water quality of shallow lakes is well documented. However, a search of the literature reveals no deterministic mass-balance eutrophication models that explicitly include resuspension. We modified the Lake Okeeehobee water quality model - which uses the Water Analysis Simulation Package (WASP) to simulate algal dynamics and phosphorus, nitrogen, and oxygen cycles - to include inorganic suspended solids and algorithms that: (1) define changes in depth with changes in volume; (2) compute sediment resuspension based on bottom shear stress; (3) compute partition coefficients for ammonia and ortho-phosphorus to solids; and (4) relate light attenuation to solids concentrations. The model calibration and validation were successful with the exception of dissolved inorganic nitrogen species which did not correspond well to observed data in the validation phase. This could be attributed to an inaccurate formulation of algal nitrogen preference and/or the absence of nitrogen fixation in the model. The model correctly predicted that the lake is lightlimited from resuspended solids, and algae are primarily nitrogen limited. The model simulation suggested that biological fluxes greatly exceed external loads of dissolved nutrients; and sedimentwater interactions of organic nitrogen and phosphorus far exceed external loads. A sensitivity analysis demonstrated that parameters affecting resuspension, settling, sediment nutrient and solids concentrations, mineralization, algal productivity, and algal stoichiometry are factors requiring further study to improve our understanding of the Lake Okeechobee ecosystem.

James, R.T.; Martin, J.; Wool, T.; Wang, P.-F.

1997-01-01

130

Heating of domestic water by waste heat recovery from household refrigerating equipment  

NASA Astrophysics Data System (ADS)

Heat from a 370 l deep freeze was used to heat water in a 250 l boiler. Both units were made from mass produced components. Tests show that the functions of cooling and deep freezing units can be effectively combined with one warm water boiler. The necessary expenditure for the appliance is, however, only economical with deep freezing units because with normal domestic refrigerators the amount of waste heat is too small. The economy of the unit could be considerably increased by the development of a mass produced motor compressor with a sufficiently large oil cooler to accomplish an optimum thermal insulation of the motor compressor surface area.

Reil, J.; Kaster, B.; Wegner, M.

1982-09-01

131

Influence of sample manipulation on contaminant flux and toxicity at the sediment–water interface  

Microsoft Academic Search

Toxicities of sediments from San Diego and San Francisco Bays were compared in laboratory experiments using sea urchin (Strongylocentrotus purpuratus) embryos exposed to pore water and at the sediment–water interface (SWI). Toxicity was consistently greater to embryos exposed at the SWI to intact (unhomogenized) sediment samples relative to homogenized samples. Measurement of selected trace metals indicated considerably greater fluxes of

B. S. Anderson; J. W. Hunt; B. M. Phillips; R. Fairey; H. M. Puckett; M. Stephenson; K. Taberski; J. Newman; R. S. Tjeerdema

2001-01-01

132

Field Evaluation Of Arsenic Speciation In Sediments At The Ground Water/Surface Water Interface  

EPA Science Inventory

The speciation and mineralogy of sediments contaminated with arsenic at the ground water/surface water interface of the Ft. Devens Super Fund Site in Ft. Devens, MA were determined using X-ray absorption fine structure and X-ray diffraction spectroscopy. Speciation and mineralog...

133

THE RELATIONSHIP OF BIOACCUMULATIVE CHEMICALS IN WATER AND SEDIMENT TO RESIDUES IN FISH: A VISUALIZATION APPROACH  

EPA Science Inventory

A visualization approach is developed and presented for depicting and interpreting bioaccumulation relationships and data, i.e., bioaccumulation factors (BAFs), biota-sediment accumulation factors (BSAFs) and chemical residues in fish, using water-sediment chemical concentration ...

134

Dynamics of particle clouds in ambient currents with application to open-water sediment disposal  

E-print Network

Open-water sediment disposal is used in many applications around the world, including land reclamation, dredging, and contaminated sediment isolation. Timely examples include the land reclamation campaign currently underway ...

Gensheimer, Robert James, III

2010-01-01

135

INTERACTION OF METALS AND ORGAINIC CARBON COLLOIDS IN ANOXIC INTERSTITIAL WATERS OF MARINE SEDIMENTS  

EPA Science Inventory

Marine colloids are an important component of natural water geochemistry critical to the cycling, speciation and bioavailability of metals in marine sediments. In sediment, metals exist in three phases: particulate, colloidal and dissolved. Dissolved metal concentrations have bee...

136

Mercury cycling between the water column and surface sediments in a contaminated area  

Microsoft Academic Search

Mercury cycling in the water column and upper sediments of a contaminated area, the Largo do Laranjo, Aveiro (Portugal), was evaluated after determination of reactive and non-reactive mercury concentrations in the water column and pore waters of sediments, collected in several places of this bay. In the water column, reactive mercury concentrations varied between 10 and 37pmoldm?3, the highest values

Elsa Ramalhosa; Susana Río Segade; Eduarda Pereira; Carlos Vale; Armando Duarte

2006-01-01

137

Assessing the fate of dredged sediments placed in open-water sites, Northern Chesapeake Bay  

USGS Publications Warehouse

An integrated series of field studies and experiments have been carried out on dredged sediments placed in open water sites in Northern Chesapeake Bay. The studies include: (1) examination of the potential for fluidized sediment flow, (2) quantifying the volumetric changes that the sediments undergo during dredging process and subsequent to deposition, (3) estimating parameters for cohesive sediment erosion models from field data on currents and suspended sediment concentrations, and (4) incorporating the erosion model parameters and sediment transport equation into a 3-D hydrodynamic model for the upper Chesapeake Bay to predict transport directions and setting sites of eroded sediments under a variety of seasonal weather and river flow conditions.

Halka, Jeffrey; Panageotou, William; Sanford, Lawrence; Yu-Chou, Shenn

1994-01-01

138

Assessing domestic water use habits for more effective water awareness campaigns during drought periods: a case study in Alicante, Eastern Spain  

NASA Astrophysics Data System (ADS)

The design of water awareness campaigns could benefit from knowledge on the specific characteristics of domestic water use and of the factors that may influence certain water consumption habits. This paper investigates water use in 450 households of 10 municipalities of drought prone Alicante (Spain) with the objective of increasing knowledge about existing domestic water behavior and therefore help to improve the design and implementation of future water awareness campaigns. The survey results indicate that users already follow many of the conservation practices mentioned in messages. Moreover, campaigns need to take into account the differences in water use and habits derived from differences in urban models (concentrated or disperse).

March, H.; Hernández, M.; Saurí, D.

2014-11-01

139

Succession in a microbial community associated with chitin in Lake Erie sediment and water  

SciTech Connect

Slides coated with reprecipitated chitin were buried in Lake Erie sediments under laboratory conditions. Changes in the microbial community on the slide were studied over time, in varying depths of the water and sediment column, and in anaerobic and aerobic zones of the sediment. Bacterial activity in the overlying water was highest after incubation of 2-7 days. Sediment populations were greatest from 7 days (aerobic zone) to 13 days (anaerobic zone). (11 photos, numerous references, 1 table)

Warnes, C.E.; Randles, C.I.

1980-11-01

140

Evaluation of toxicity: Whole-sediment versus overlying-water exposures with amphipod Hyalella azteca  

USGS Publications Warehouse

A laboratory study was conducted to evaluate the toxicity of whole-sediment versus overlying-water exposures to the amphipod Hyalella azteca using field-collected sediments. Severe toxic effects (5-63% survival) were observed with amphipods exposed for 10 d in direct contact with sediment. In contrast, amphipods exposed only to overlying water in these sediment exposures did not exhibit any toxic effects.

Ingersoll, C.G.; Ivey, C.D.; Brunson, E.L.; Hardesty, D.K.; Kemble, N.E.

2000-01-01

141

Evaluating Domestic Hot Water Distribution System Options With Validated Analysis Models  

SciTech Connect

A developing body of work is forming that collects data on domestic hot water consumption, water use behaviors, and energy efficiency of various distribution systems. A full distribution system developed in TRNSYS has been validated using field monitoring data and then exercised in a number of climates to understand climate impact on performance. This study builds upon previous analysis modelling work to evaluate differing distribution systems and the sensitivities of water heating energy and water use efficiency to variations of climate, load, distribution type, insulation and compact plumbing practices. Overall 124 different TRNSYS models were simulated. Of the configurations evaluated, distribution losses account for 13-29% of the total water heating energy use and water use efficiency ranges from 11-22%. The base case, an uninsulated trunk and branch system sees the most improvement in energy consumption by insulating and locating the water heater central to all fixtures. Demand recirculation systems are not projected to provide significant energy savings and in some cases increase energy consumption. Water use is most efficient with demand recirculation systems, followed by the insulated trunk and branch system with a central water heater. Compact plumbing practices and insulation have the most impact on energy consumption (2-6% for insulation and 3-4% per 10 gallons of enclosed volume reduced). The results of this work are useful in informing future development of water heating best practices guides as well as more accurate (and simulation time efficient) distribution models for annual whole house simulation programs.

Weitzel, E.; Hoeschele, M.

2014-09-01

142

AVAILABILITY OF DOMESTIC WATER AND SANITATION IN HOUSEHOLDS: A GENDER PERSPECTIVE USING SURVEY DATA IN SOUTH AFRICA  

Microsoft Academic Search

The availability of domestic water and adequate sanitation is high on the agenda of both international and local communities. Despite concerted efforts to achieve the targets set by the Millennium Development Goal (MDG) for water and sanitation, current levels of water supply and adequate sanitation coverage remain largely inadequate. Various contributing factors, including economic and demographic pressures, account for the

Esther W. DUNGUMARO

143

INSTALLATION CERTIFICATE CF-6R-MECH-02 Solar Domestic Hot Water Systems (SDHW) (Page 1 of 1)  

E-print Network

INSTALLATION CERTIFICATE CF-6R-MECH-02 Solar Domestic Hot Water Systems (SDHW) (Page 1 of 1) Site. §150(j)4: Solar water-heating system and/or/collectors are certified by the Solar Rating and Certification Corporation. Solar water-heating systems storage is no less than the value used in the attached

144

Domestic water carrying and its implications for health: a review and mixed methods pilot study in Limpopo Province, South Africa  

Microsoft Academic Search

BACKGROUND: Lack of access to safe water remains a significant risk factor for poor health in developing countries. There has been little research into the health effects of frequently carrying containers of water. The aims of this study were to better understand how domestic water carrying is performed, identify potential health risk factors and gain insight into the possible health

Jo-Anne L Geere; Paul R Hunter; Paul Jagals

2010-01-01

145

One Machine for Heating Cooling & Domestic Hot Water: Multi-Function Heat Pumps to Enable Zero Net Energy Homes  

E-print Network

to experience this change as air-source heat-pump water heaters deliver obvious energy savings over electric-resistance water heaters; and (arguably) also beat condensing gas- fired systems in terms of source energy that provide heating, cooling, and domestic hot water services in residences. This combination of functions

California at Davis, University of

146

Concentrations of Elements in Sediments and Selective Fractions of Sediments, and in Natural Waters in Contact with Sediments from Lake Roosevelt, Washington, September 2004  

USGS Publications Warehouse

Twenty-eight composite and replicate sediment samples from 8 Lake Roosevelt sites were collected and analyzed for 10 alkali and alkaline earth elements, 2 non-metals, 20 metals, and 4 lanthanide and actinide elements. All elements were detected in all sediment samples except for silver (95 percent of the elements detected for 1,008 analyses), which was detected only in 4 samples. Sequential selective extraction procedures were performed on single composite samples from the eight sites. The percentage of detections for the 31 elements analyzed ranged from 76 percent for the first extraction fraction using a weak extractant to 93 percent for the four-acid dissolution of the sediments remaining after the third sequential selective extraction. Water samples in various degrees of contact with the sediment were analyzed for 10 alkali and alkaline earth elements, 5 non-metals, 25 metals, and 16 lanthanide and actinide elements. The filtered water samples included 10 samples from the reservoir water column at 8 sites, 32 samples of porewater, 55 samples from reservoir water overlying sediments in 8 cores from the site incubated in a field laboratory, and 24 water samples that were filtered after being tumbled with sediments from 8 sites. Overall, the concentrations of only 37 percent of the 6,776 analyses of the 121 water samples were greater than the reporting limit. Selenium, bismuth, chromium, niobium, silver, and zirconium were not detected in any water samples. The percentage of concentrations for the water samples that were above the reporting limit ranged from 14 percent for the lanthanide and actinide elements to 77 percent for the alkali and alkaline earth elements. Concentrations were greater than reporting limits in only 23 percent of the analyses of reservoir water and 29 percent of the analyses of reservoir water overlying incubation cores. In contrast, 47 and 48 percent of the concentrations of porewater and water samples tumbled with sediments, respectively, were greater than the reporting limit.

Paulson, Anthony J.; Wagner, Richard J.; Sanzolone, Richard F.; Cox, Steven E.

2006-01-01

147

Heteroaggregation and sedimentation rates for nanomaterials in natural waters.  

PubMed

Exposure modeling of engineered nanomaterials requires input parameters such as sedimentation rates and heteroaggregation rates. Here, we estimate these rates using quiescent settling experiments under environmentally relevant conditions. We investigated 4 different nanomaterials (C60, CeO2, SiO2-Ag and PVP-Ag) in 6 different water types ranging from a small stream to seawater. In the presence of natural colloids, sedimentation rates ranged from 0.0001 m d(-1) for SiO2-Ag to 0.14 m d(-1) for C60. The apparent rates of heteroaggregation between nanomaterials and natural colloids were estimated using a novel method that separates heteroaggregation from homoaggregation using a simplified Smoluchowski-based aggregation-settling equation applied to data from unfiltered and filtered waters. The heteroaggregation rates ranged between 0.007 and 0.6 L mg(-1) day(-1), with the highest values observed in seawater. We argue that such system specific parameters are key to the development of dedicated water quality models for ENMs. PMID:24119930

Quik, J T K; Velzeboer, I; Wouterse, M; Koelmans, A A; van de Meent, D

2014-01-01

148

Response of coliform populations in streambed sediment and water column to changes in nutrient concentrations in water.  

PubMed

As sediments increasingly become recognized as reservoirs of indicator and pathogen microorganisms, an understanding of the persistence of indicator organisms becomes important for assessment and predictions of microbial water quality. The objective of this work was to observe the response of water column and sediment coliform populations to the change in nutrient concentrations in the water column. Survival experiments were conducted in flow-through chambers containing sandy sediments. Bovine feces were collected fresh and introduced into sediment. Sixteen days later, the same fecal material was autoclaved and diluted to provide three levels - 1×, 0.5×, and 0.1× of nutrient concentrations - spike in water column. Total coliforms, Escherichia coli, and total aerobic heterotrophic bacterial concentrations were monitored in water and sediment. Bacteria responded to the nutrient spike with initial growth both in the water column and in sediment. The response of bacterial concentrations in water column was nonlinear, with no significant changes at 0.1 and .5× spikes, but a substantial change at 1× spike. Bacteria in sediment responded to the spikes at all added nutrient levels. Coliform inactivation rates both in sediment and in water after the initial growth occurred, were not significantly different from the inactivation rates before spike. These results indicate that introduction of nutrients into the water column results in nonlinear response of E. coli concentrations both in water and in sediments, followed by the inactivation with the same rate as before introduction of nutrients. PMID:24839925

Shelton, D R; Pachepsky, Y A; Kiefer, L A; Blaustein, R A; McCarty, G W; Dao, T H

2014-08-01

149

Sediment-water interactions and their effects upon water quality. (Latest citations from the NTIS bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning the testing and evaluation of fresh-water sediments. Citations discuss assessment and remediation of contaminated sediments, monitoring systems, sediment transport, water pollution effects, water traffic, habitats and fisheries, and the effect of dredging operation. National programs, acts, regulations, and criteria are examined.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

NONE

1995-09-01

150

Molecular markers for identifying municipal, domestic and agricultural sources of organic matter in natural waters.  

PubMed

Molecular markers can be used to determine the sources of organic pollution in water. This review summarizes progress made during the last two decades in identifying reliable molecular markers to distinguish pollution from sewage, animal production, and other sources. Two artificial sweeteners, sucralose and acesulfame-K, are sufficiently stable to be molecular markers and easily associated with domestic wastewater. Waste from different animal species may be distinguished by profiling fecal sterols and bile acids. Other markers which have been evaluated, including caffeine, detergent components, and compounds commonly leached from landfills are discussed. PMID:24200048

Harwood, John J

2014-01-01

151

Thermal Energy Storage using PCM for Solar Domestic Hot Water Systems: A Review  

NASA Astrophysics Data System (ADS)

Thermal energy storage using phase chase materials (PCM) has received considerable attention in the past two decades for time dependent energy source such as solar energy. From several experimental and theoretical analyses that have been made to assess the performance of thermal energy storage systems, it has been demonstrated that PCM-based systems are reliable and viable options. This paper covers such information on PCMs and PCM-based systems developed for the application of solar domestic hot water system. In addition, economic analysis of thermal storage system using PCM in comparison with conventional storage system helps to validate its commercial possibility. From the economic analysis, it is found that, PCM based solar domestic hot water system (SWHS) provides 23 % more cumulative and life cycle savings than conventional SWHS and will continue to perform efficiently even after 15 years due to application of non-metallic tank. Payback period of PCM-based system is also less compared to conventional system. In conclusion, PCM based solar water heating systems can meet the requirements of Indian climatic situation in a cost effective and reliable manner.

Khot, S. A.; Sane, N. K.; Gawali, B. S.

2012-06-01

152

Solar domestic hot water system, a comparative study and storage tank investigation  

NASA Astrophysics Data System (ADS)

A computer program was developed to simulate five typical solar domestic hot water systems which included both thermosyphon and pumped designs that were assembled and tested. Numerical simulations of these systems were verified by comparison to experimental results. Predicted thermal performance, i.e., collector inlet and outlet temperatures, and auxiliary energy requirements were found to be in excellent agreement with experiments. The computer program was then used to predict the long term annual performance of the various systems at 14 different locations throughout California. Load size and load distribution were also varied. Economic analyses were performed on each system with the goal of identifying the most economical system at each location under a prescribed load (gallons/day) size and distribution pattern (time of day for hot water use). It was found that in almost all cases the two tank thermosyphon system was the most cost effective system for all locations, load sizes and distributions and shows promise of being the most widely used solar domestic hot water system.

Young, M. F.

1980-03-01

153

Hexachlorobenzene uptake by fathead minnows and macroinvertebrates in recirculating sediment/water systems.  

PubMed

Fathead minnows (Pimephales promelas), the worm, Lumbriculus variegatus, and the amphipods Hyalella azteca and Gammarus lacustris were exposed to hexachlorobenzene (HCB) in water with and without a bed of HCB-spiked sediment. Water HCB concentrations were maintained by recirculation through HCB-packed columns. Recirculating HCB-bound particulates and possibly eroded HCB particulates were an added source of HCB in addition to the sediment bed. Significant bioaccumulation of HCB in animal tissues was observed in water-only and water-sediment exposures. The presence of the HCB-spiked sediment did not result in a significant increase in the uptake of HCB by the organisms, but there was a substantial increase in sediment HCB levels over time. Higher tissue HCB levels in aquaria without sediment suggest that the sediment was a more efficient sink for HCB than the organisms. PMID:2331142

Schuytema, G S; Krawczyk, D F; Griffis, W L; Nebeker, A V; Robideaux, M L

1990-01-01

154

Hexachlorobenzene uptake by fathead minnows and macroinvertebrates in recirculating sediment/water systems  

SciTech Connect

Fathead minnow (Pimephales promelas), the worm, Lumbriculus variegatus, and the amphipods Hyalella azteca and Gammarus lacustris were exposed to hexachlorobenzene (HCB) in water with and without a bed of HCB-spiked sediment. Water HCB concentrations were maintained by recirculation through HCB-packed columns. Recirculating HCB-bound particulates and possibly eroded HCB particulates were an added source of HCB in addition to the sediment bed. Significant bioaccumulation of HCB in animal tissues was observed in water-only and water-sediment exposures. The presence of the HCB-spiked sediment did not result in a significant increase in the uptake of HCB by the organisms, but there was a substantial increase in sediment HCB levels over time. Higher tissue HCB levels in aquaria without sediment suggest that the sediment was a more efficient sink for HCB than the organisms.

Schuytema, G.S.; Krawczyk, D.F.; Griffis, W.L.; Nebeker, A.V.; Robideaux, M.L.

1990-01-01

155

Isolation of enteroviruses from water, suspended solids, and sediments from Galveston Bay: survival of poliovirus and rotavirus adsorbed to sediments.  

PubMed Central

The distribution and quantitation of enteroviruses among water, suspended solids, and compact sediments in a polluted estuary are described. Samples were collected sequentially from water, suspended solids, fluffy sediments (uppermost layer of bottom sediments), and compact sediment. A total of 103 samples were examined of which 27 (26%) were positive for virus. Polioviruses were recovered most often, followed by coxsackie B viruses and echoviruses 7 and 29. Virus was found most often attached to suspended solids: 72% of these samples were positive, whereas only 14% of water samples without solids yielded virus. Fluffy sediments yielded virus in 47% of the samples, whereas only 5% of compact bottom-sediment samples were positive. When associated with solids, poliovirus and rotavirus retained their infectious quality for 19 days. The same viruses remained infectious for only 9 days when freely suspended in seawater. Collection of suspended solids at ambient water pH appears to be very useful for the detection of virus; it has advantages over collecting and processing large volumes of water, with accompanying pH adjustment and salt addition for processing. PMID:6091548

Rao, V C; Seidel, K M; Goyal, S M; Metcalf, T G; Melnick, J L

1984-01-01

156

Isolation of enteroviruses from water, suspended solids, and sediments from Galveston Bay: survival of poliovirus and rotavirus adsorbed to sediments.  

PubMed

The distribution and quantitation of enteroviruses among water, suspended solids, and compact sediments in a polluted estuary are described. Samples were collected sequentially from water, suspended solids, fluffy sediments (uppermost layer of bottom sediments), and compact sediment. A total of 103 samples were examined of which 27 (26%) were positive for virus. Polioviruses were recovered most often, followed by coxsackie B viruses and echoviruses 7 and 29. Virus was found most often attached to suspended solids: 72% of these samples were positive, whereas only 14% of water samples without solids yielded virus. Fluffy sediments yielded virus in 47% of the samples, whereas only 5% of compact bottom-sediment samples were positive. When associated with solids, poliovirus and rotavirus retained their infectious quality for 19 days. The same viruses remained infectious for only 9 days when freely suspended in seawater. Collection of suspended solids at ambient water pH appears to be very useful for the detection of virus; it has advantages over collecting and processing large volumes of water, with accompanying pH adjustment and salt addition for processing. PMID:6091548

Rao, V C; Seidel, K M; Goyal, S M; Metcalf, T G; Melnick, J L

1984-08-01

157

Rapid, high-precision potentiometric titration of alkalinity in ocean and sediment pore waters  

Microsoft Academic Search

A system for rapid, high precision potentiometric determination of alkalinity in sea water and sediment pore water is presented. Two titration units were used: a 40 ml unit for seawater and a small volume unit for sediment pore water. Titration time was normally less than 10 minutes per sample, including sample exchange. With a 40 ml sample volume, the relative

Conny Haraldsson; Leif G. Anderson; Martin Hassellöv; Stefan Hulth; Kristina Olsson

1997-01-01

158

Mercury Species and Other Selected Constituent Concentrations in Water, Sediment, and Biota of  

E-print Network

Mercury Species and Other Selected Constituent Concentrations in Water, Sediment, and Biota Data Series 658 #12;#12;Mercury Species and Other Selected Constituent Concentrations in Water.J., 2012, Mercury species and other selected constituent concentrations in water, sediment, and biota

159

Degradation, Fate and Bioavailability of Sulfamethazine in Pond Water and Sediment  

Technology Transfer Automated Retrieval System (TEKTRAN)

Antibiotics from animal agriculture are found in surface waters and stream sediments. We investigated the degradation and fate of sulfamethazine in small pond water and sediment microcosms. Sulfamethazine [14C-phenyl] was added to the water phase directly, or in a dilute swine manure solution that s...

160

Metabolism of niclosamide in sediment and water systems  

USGS Publications Warehouse

A series of experiments analyzed the kinetics and mechanisms of [ 14C]niclosamide degradation. The aerobic aquatic metabolism of [ 14C]niclosamide was studied in nonsterile river water/sediment mixtures. Test systems, maintained under aerobic conditions, were treated with niclosamide and incubated in the dark at 25.0 ?? 1.0 ??C for 30 days. Half-lives of 4.9 and 5.4 days were calculated for the chlorosalicylic acid- and chloronitroaniline-labeled test systems, respectively. From 0 to 21 days after treatment (DAT), the only metabolism product observed in either test system was aminoniclosamide. At the final sampling interval, five peaks were resolved from the chlorosalicylic acid label, and three peaks were resolved from the chloronitroaniline label test substance. By 30 DAT, sediment-bound residues represented ???70% of the observed radioactivity. For the anaerobic aquatic metabolism of [14C]niclosamide, test systems were incubated under anaerobic conditions for 365 days. Half-lives of 0.65 day for the chlorosalicylic acid label and 2.79 days for the chloronitroaniline label were calculated. From 0 to 3 DAT, niclosamide was first transformed into aminoniclosamide. Aminoniclosamide is readily formed, as it was observed in the chlorosalicylic acid label 0 DAT sampling. Several minor metabolites were observed in the water and sediment extracts. None of these metabolites were formed to a significant amount until the parent niclosamide dissipated below the detection limit. Two of the byproducts from these metabolism studies are polar unknowns eluting at 3 and 5 min by HPLC, similar to the unknowns observed in aqueous photolysis studies.

Graebing, P.W.; Chib, J.S.; Hubert, T.D.; Gingerich, W.H.

2004-01-01

161

STAND, A DYNAMIC MODEL FOR SEDIMENT TRANSPORT AND WATER QUALITY. (R825758)  

EPA Science Inventory

We introduce a new model–STAND (Sediment-Transport-Associated Nutrient Dynamics)–for simulating stream flow, sediment transport, and the interactions of sediment with other attributes of water quality. In contrast to other models, STAND employs a fully dynamic ba...

162

Continental Shelf Research 24 (2004) 20292043 A conceptual model for river water and sediment dispersal in  

E-print Network

of freshwater and sediment to the eastern Santa Barbara Channel during brief, episodic discharge events mouth on a peak day of river discharge revealed that sediment rapidly settled from the freshened surface sediment 1. Introduction Rivers discharging into coastal margins are an important fresh water source

Washburn, Libe

163

Risk factors for contamination of domestic hot water systems by legionellae.  

PubMed Central

To assess risk factors associated with the contamination of the domestic environment by legionellae, 211 houses in the Quebec City area were randomly selected and water samples were collected from the hot water tank, the shower heads, and the most frequently used faucet. After centrifugation, concentrated samples were seeded in triplicate on BCYE and GPV media. Data on the characteristics of the hot water system and plumbing in the house and on the personal habits of the occupants were collected for each house. Among these 211 houses, hot water was provided by either an oil or gas heater in 33 and by an electric heater in 178. Legionellae were isolated from none of the samples from houses with oil or gas heaters and from 39% (69 of 178) of those with electric water heaters (P less than 0.0001). This association remained highly significant after control for water temperature and other variables in a stratified analysis. In the 178 houses with an electric heater, 12% of the faucets, 15% of the shower heads, and 37% of the water heaters were contaminated. Legionella pneumophila serogroups 2 and 4 were the most frequently isolated strains. Logistic regression showed that factors associated with electric water heater contamination were (i) location of the house in older districts of the city (P less than 0.0001), (ii) old age of the water heater (P = 0.003), and (iii) low water temperature (P = 0.05). Contamination of the water heater was the only factor significantly associated with the contamination of peripheral outlets (P less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1768104

Alary, M; Joly, J R

1991-01-01

164

Resuspension and settling of helminth eggs in water: Interactions with cohesive sediments.  

PubMed

Helminth parasite eggs in low quality water represent main food safety and health hazards and are therefore important indicators used to determine whether such water can be used for irrigation. Through sedimentation helminth eggs accumulate in the sediment, however resuspension of deposited helminth eggs will lead to increased concentration of suspended eggs in the water. Our study aimed to determine the erodibility (erosion rate and erosion threshold) and settling velocity of Ascaris and Trichuris eggs as well as cohesive sediment at different time points after incorporation into the sediment. Cohesive sediment collected from a freshwater stream was used to prepare a sediment bed onto which helminth eggs were allowed to settle. The erodibility of both sediment and helminth eggs was found to decrease over time indicating that the eggs were incorporated into the surface material of the bed and that this material was stabilized through time. This interaction between eggs and bulk sediment was further manifested in an increased settling velocity of suspended eggs when sediment was present in the suspension as compared to a situation with settling in clean water. The incorporation into the sediment bed and the aggregation with sediment particles decrease the mobility of both helminth egg types. Our findings document that helminth eggs should not be viewed as single entities in water systems when modelling the distribution of eggs since both erodibility and settling velocity of eggs are determined by mobility of the sediment present in the water stream. Recalculation of the erosion threshold for helminth eggs and sediment showed that even at relatively low current velocities i.e. 0.07-0.12ms(-1) newly deposited eggs will be mobile in open irrigation channels. These environmental factors affecting resuspension must be taken into account when developing models for sedimentation of helminth eggs in different water systems. PMID:22591818

Sengupta, Mita E; Andersen, Thorbjørn J; Dalsgaard, Anders; Olsen, Annette; Thamsborg, Stig M

2012-08-01

165

Factors Affecting Domestic Water Consumption in Rural Households upon Access to Improved Water Supply: Insights from the Wei River Basin, China  

PubMed Central

Comprehensively understanding water consumption behavior is necessary to design efficient and effective water use strategies. Despite global efforts to identify the factors that affect domestic water consumption, those related to domestic water use in rural regions have not been sufficiently studied, particularly in villages that have gained access to improved water supply. To address this gap, we investigated 247 households in eight villages in the Wei River Basin where three types of improved water supply systems are implemented. Results show that domestic water consumption in liters per capita per day was significantly correlated with water supply pattern and vegetable garden area, and significantly negatively correlated with family size and age of household head. Traditional hygiene habits, use of water appliances, and preference for vegetable gardening remain dominant behaviors in the villages with access to improved water supply. Future studies on rural domestic water consumption should pay more attention to user lifestyles (water appliance usage habits, outdoor water use) and cultural backgrounds (age, education). PMID:23977190

Fan, Liangxin; Liu, Guobin; Wang, Fei; Geissen, Violette; Ritsema, Coen J.

2013-01-01

166

SIMULATION OF THE INTERACTION OF A SOLAR DOMESTIC HOT WATER TANK SYSTEM WITH A COMPACT PLATE HEAT EXCHANGER  

Microsoft Academic Search

This research uses computational fluid dynamics (CFD) to predict the interaction of a natural convection driven side-arm heat exchanger with a hot water storage tank. In this paper, a model of a solar domestic hot water tank with vertical compact plate natural convection heat exchanger has been incorporated into the commercial CFD software ANSYS CFX. In order to make the

Danish J. Nizami; Marilyn F. Lightstone; Stephen Harrison; Cynthia Cruickshank

167

Determining the optimum solar water pumping system for domestic use, livestock water, or irrigation  

Technology Transfer Automated Retrieval System (TEKTRAN)

For several years we have field tested many different types of solar powered water pumping systems. In this paper, several steps are given to select a solar-PV water pumping system. The steps for selection of stand-alone water pumping system were: deciding whether a wind or solar water pumping sys...

168

Roof Water Harvesting for Domestic Water Security: Who Gains and Who Loses?  

Microsoft Academic Search

Roof water harvesting is being widely promoted as a panacea for the growing drinking water crisis in India and many underdeveloped and developing countries. This article analyzes the scope, physical feasibility, and economic viability of roof water harvesting systems across classes and under different physical and socioeconomic situations. This article argues that roof water harvesting systems (RWHS) are not alternative

M. Dinesh Kumar

2004-01-01

169

Impact of total organic carbon (in sediments) and dissolved organic carbon (in overlying water column) on Hg sequestration by coastal sediments from the central east coast of India.  

PubMed

Total organic carbon (TOC) (in sediment) and dissolved organic matter (DOM) (in water column) play important roles in controlling the mercury sequestration process by the sediments from the central east coast of India. This toxic metal prefers to associate with finer size particles (silt and clay) of sediments. Increasing concentrations of DOM in overlying water column may increase complexation/reduction processes of Hg(2+) within the water column and decrease the process of Hg sequestration by sediments. However, high concentrations of DOM in water column may increase Hg sequestration process by sediments. PMID:24355570

Chakraborty, Parthasarathi; Sharma, Brijmohan; Babu, P V Raghunath; Yao, Koffi Marcellin; Jaychandran, Saranya

2014-02-15

170

Distributions of pesticides and organic contaminants between water and suspended sediment, San Francisco Bay, California  

USGS Publications Warehouse

Suspended-sediment and water samples were collected from San Francisco Bay in 1991 during low river discharge and after spring rains. All samples were analyzed for organophosphate, carbamate, and organochlorine pesticides; petroleum hydrocarbons; biomarkers; and polynuclear aromatic hydrocarbons. The objectives were to determine the concentrations of these contaminants in water and suspended sediment during two different hydrologic conditions and to determine partition coefficients of the contaminants between water and sediment. Concentrations of hydrophobic contaminants, such as polynuclear aromatic hydrocarbons, varied with location of sample collection, riverine discharge, and tidal cycle. Concentrations of hydrophobic contaminants in suspended sediments were highest during low river discharge but became diluted as agricultural soils entered the bay after spring rains. Polynuclear aromatic hydrocarbons defined as dissolved in the water column were not detected. The concentrations sorbed on suspended sediments were variable and were dependent on sediment transport patterns in the bay. In contrast, the relatively hydrophilic organophosphate pesticides, such as chlorpyrifos and diazinon, has a more uniform concentration in suspended sediment. These pesticides were detected only after spring rains. Most of the measured diazinon, at least 98% for all samples, was in the dissolved phase. Measured partition coefficients for diazinon generally were uniform, which suggests that suspended-sediment concentrations were close to equilibrium with dissolved concentrations. The concentration of diazinon sorbed to suspended sediments, at any given sampling site, was driven primarily by the more abundant solution concentration. The concentrations of diazinon sorbed to suspended sediments, therefore, were independent of the patterns of sediment movement. ?? 1993 Estuarine Research Federation.

Domagalski, J.L.; Kuivila, K.M.

1993-01-01

171

Chemical quality of surface waters and sedimentation in the Saline River basin, Kansas  

USGS Publications Warehouse

This report gives the results of an investigation of the sediment and dissolved minerals that are transported by the Saline River and its tributaries. The Saline River basin is in western and central Kansas; it is long and narrow and covers 3,420 square miles of rolling plains, which is broken in some places by escarpments and small areas of badlands. In the western part the uppermost bedrock consists predominantly of calcareous elastic sedimentary rocks of continental origin of Pliocene age and in most places is covered by eolian deposits of Pleistocene and Recent age. In the central part the ex posed bedrock consists predominantly of calcareous marine sedimentary rocks of Late Cretaceous age. In the eastern part the exposed bedrock consists mainly of noncalcareous continental and littoral elastic sedimentary rocks of Early Cretaceous and Permian age. Fluvial deposits are in the valleys, and eolian materials are present over much of the uplands. Average precipitation increases rather uniformly from about 18 inches per year in the west to almost 28 inches per year in the east. Runoff is not affected by irrigation nor regulated by large structures, but it is closely related to precipitation. Average runoff increases from less than 0.2 inch per year in the west to more than 1.5 inches per year in the east. Aquifers of the flood-plain and terrace deposits and of the Cretaceous Dakota Sandstone are the major sources of ground-water accretion to the streams. In the upper reaches of the Saline River, the water is only slightly mineralized; during the period of record the specific conductance near Wakeeney never exceeded 750 micromhos per centimeter. In the lower reaches, however, the water is slightly mineralized during periods of high flow and is highly mineralized during periods of low flow; the specific conductance near Russell exceeded 1,500 micromhos per centimeter more than 80 percent of the time. Near Russell, near Wilson, and at Tescott the water is of the calcium bicarbonate type when the specific conductance is less than about 1,000 micromhos per centimeter, but it is of the sodium chloride type when the specific conductance is more than about 1,500 micromhos per centimeter. The water is off the calcium bicarbonate, sodium bicarbonate, or sodium chloride type when the conductance is between 1,000 and 1,500 micromhos per centimeter. Most of the increase in mineralization of the water is caused by inflow of highly mineralized ground water. The ground-water inflow was estimated to be 22 percent of the total streamflow at Tescott in 1948 and 60 percent in 1952. Mineralization increases and water quality deteriorates progressively downstream along nearly the entire Saline River, especially in the part of the area directly underlain by the Dakota Sandstone between the vicinities of Fairport and Wilson: sodium and chloride are the principal constituents of water contributed by the Dakota. The total percentage of the salt in the Saline River that comes from oil-field brines is considered to be small. The water in the upper Saline River is of good quality for domestic use except that it is hard; the water in the lower Saline River is of poor quality for domestic use because most of the time it is highly mineralized, is hard, and contains high concentrations of chloride and sulfate. In the upper reaches of the river, the water is of good quality for irrigation. In the lower reaches, if the water were impounded in a reservoir, it would be of good quality for irrigation during years of high flow and of very poor quality during years of low flow. The water in the lower reaches is of poor quality for industrial use because it is highly mineralized most of the tinge. Relations of suspended-sediment discharge to water discharge were used with the long-term streamflow duration curves to compute the long-term aver age suspended-sediment discharges and concentrations at five indications. Sediment discharge is closely related to runoff. S

Jordan, Paul Robert; Jones, B.F.; Petri, Lester R.

1964-01-01

172

Water quality effects of herded stream crossings by domestic sheep bands.  

PubMed

Livestock impacts on total suspended solids (TSS) and pathogen (e.g., ) levels in rangeland streams are a serious concern worldwide. Herded stream crossings by domestic sheep () are periodic, necessary managerial events on high-elevation rangelands, but their impacts on stream water quality are largely unknown. We evaluated the effects of herded, one-way crossings by sheep bands (about 2000 individuals) on TSS and concentration and load responses in downstream waters. Crossing trials were conducted during the summers of 2005 and 2006 on two reaches within each of three perennial streams in the Centennial Mountains of eastern Idaho and southwestern Montana. Water samples were collected at 2-min intervals at an upstream background station and at stations 25, 100, 500, and 1500 m downstream just before and during each crossing trial. Crossings produced substantial increases in TSS and concentrations and loads downstream, but these concentration increases were localized and short lived. Maximum TSS concentration was highest 25 m downstream, declined as a function of downstream distance, and at 500 m downstream was similar to background. Post-peak TSS concentrations at all downstream stations decreased to <25 mg L within 24 to 48 min after reaching their maxima. Findings for concentration and load responses were similar to that of TSS but less clear cut. Stream-crossing sheep do affect water quality; therefore, producers and resource managers should continue to evaluate the efficacy of herdsmanship techniques for reducing water quality impact. PMID:23099950

Clark, Patrick E; Moffet, Corey A; Lewis, Gregory S; Seyfried, Mark S; Hardegree, Stuart P; Pierson, Fredrick B

2012-01-01

173

Domestic rainwater harvesting to improve water supply in rural South Africa  

NASA Astrophysics Data System (ADS)

Halving the proportion of people without sustainable access to safe drinking water and basic sanitation, is one of the targets of the 7th Millennium Development Goals (MDGs). In South Africa, with its mix of developed and developing regions, 9.7 million (20%) of the people do not have access to adequate water supply and 16 million (33%) lack proper sanitation services. Domestic Rainwater Harvesting (DRWH), which provides water directly to households enables a number of small-scale productive activities, has the potential to supply water even in rural and peri-urban areas that conventional technologies cannot supply. As part of the effort to achieve the MDGs, the South African government has committed itself to provide financial assistance to poor households for the capital cost of rainwater storage tanks and related works in the rural areas. Despite this financial assistance, the legal status of DRWH remains unclear and DRWH is in fact illegal by strict application of the water legislations. Beyond the cost of installation, maintenance and proper use of the DRWH system to ensure its sustainability, there is risk of waterborne diseases. This paper explores challenges to sustainable implementation of DRWH and proposes some interventions which the South African government could implement to overcome them.

Mwenge Kahinda, Jean-marc; Taigbenu, Akpofure E.; Boroto, Jean R.

174

IDENTIFICATION OF STRESSORS IN TOXIC SEDIMENTS: WHOLE SEDIMENT AND INSTITIAL WATER RESULTS  

EPA Science Inventory

Identification of stressors in aquatic systems is critical to sound assessment and management of our nation's waterways. Information from stressor identification can be useful in designing effective sediment remediation methods, assessing options for sediment disposal, allowing m...

175

The Role of Non-Conventional and Lower Quality Water for the Satisfaction of the Domestic Needs in Drought Management Plans  

Microsoft Academic Search

This chapter outlines the potential and role that underground low quality water and non conventional water (recycled grey\\u000a water, desalinated and domestic effluent water), have and can play in the preparation of drought mitigation plans especially\\u000a in relation to the satisfaction of the domestic water supply needs. Low quality underground water, if available in aquifers\\u000a within the city or village

Nicos X. Tsiourtis

176

Sedimentation of Free and Attached Cryptosporidium Oocysts and Giardia Cysts in Water  

PubMed Central

Experimental analysis of the sedimentation velocity of Cryptosporidium parvum oocysts and Giardia lamblia cysts was compared with mathematical description of their sedimentation velocities by using measurements of (oo)cyst size and density and the density and viscosity of the sedimentation medium to determine if the sedimentation kinetics of freely suspended oocysts of C. parvum and cysts of G. lamblia can be described by Stokes’ law. The theoretically calculated sedimentation kinetics showed a good agreement with the experimentally observed kinetics. Both showed a decline in sedimentation velocity over time, caused primarily by variation in (oo)cyst density. The initial apparent sedimentation velocities in Hanks balanced salt solution at 23°C was 0.35 ?m · s?1 for oocysts and 1.4 ?m · s?1 for cysts. (Oo)cysts that enter the surface water environment by discharges of biologically treated sewage may be attached to sewage particles, and this will affect their sedimentation kinetics. Therefore, (oo)cysts were mixed with settled secondary effluent. (Oo)cysts readily attached to the (biological) particles in effluent; 30% of both cysts and oocysts attached during the first minutes of mixing, and this fraction increased to approximately 75% after 24 h. The sedimentation velocity of (oo)cysts attached to secondary effluent particles increased with particle size and was (already in the smallest size fraction [1 to 40 ?m]) determined by the sedimentation kinetics of the effluent particles. The observed sedimentation velocities of freely suspended (oo)cysts are probably too low to cause significant sedimentation in surface water or reservoirs. However, since a significant proportion of both cysts and oocysts attached readily to organic biological particles in secondary effluent, sedimentation of attached (oo)cysts after discharge into surface water will probably be a significant factor in the environmental ecology of C. parvum and G. lamblia. Attachment to particles influences not only sedimentation of (oo)cysts in surface water but also their behavior in drinking water treatment processes. PMID:9797307

Medema, G. J.; Schets, F. M.; Teunis, P. F. M.; Havelaar, A. H.

1998-01-01

177

Effects of handling, temperature and storage time on sediment and pore-water chemistry and toxicity  

SciTech Connect

Effects of sediment disturbance, storage temperature (230 C and 40 C) and storage time on chemistry and toxicity of sediment and pore water were evaluated using two sediments (sandy freshwater and organic estuarine) contaminated with metals. Solid-phase (10 d with water renewal) and pore-water (96-h static) toxicity tests with Hyalella azteca were conducted upon collection and at two week intervals for 8--10 weeks. Chemistries (redox, pH, conductivity, alkalinity, ammonia, trace metals, major cations and anions) were measured at each toxicity testing interval. Following extraction, pore-water chemistry changed significantly during the initial 96 h due to oxidation reactions and CO{sub 2} equilibration. Pore water collected in situ was slightly less toxic and had major differences in water chemistry compared to pore water extracted from homogenized sediment. Storage temperature and time significantly influenced pore-water toxicity and chemistry, but had minimal effect on solid-phase toxicity. After four weeks, the highly-toxic sandy sediment became slightly less toxic in solid-phase tests and Significantly less toxic in pore-water tests, coinciding with changes in trace-metal concentrations, activities, and speciation. The estuarine sediment became slightly more toxic in both solid-phase and pore-water tests after four weeks, but returned to original levels after six and eight weeks. Sediment disturbance, storage temperature, and storage time significantly influenced toxicity and pore-water chemistry.

Lasier, P.J.; Winger, P.V.; Jackson, B.P. [Univ. of Georgia, Athens, GA (United States). National Biological Survey

1994-12-31

178

Where There Is No Toilet: Water and Sanitation Environments of Domestic and Facility Births in Tanzania  

PubMed Central

Background Inadequate water and sanitation during childbirth are likely to lead to poor maternal and newborn outcomes. This paper uses existing data sources to assess the water and sanitation (WATSAN) environment surrounding births in Tanzania in order to interrogate whether such estimates could be useful for guiding research, policy and monitoring initiatives. Methods We used the most recent Tanzania Demographic and Health Survey (DHS) to characterise the delivery location of births occurring between 2005 and 2010. Births occurring in domestic environments were characterised as WATSAN-safe if the home fulfilled international definitions of improved water and improved sanitation access. We used the 2006 Service Provision Assessment survey to characterise the WATSAN environment of facilities that conduct deliveries. We combined estimates from both surveys to describe the proportion of all births occurring in WATSAN-safe environments and conducted an equity analysis based on DHS wealth quintiles and eight geographic zones. Results 42.9% (95% confidence interval: 41.6%–44.2%) of all births occurred in the woman's home. Among these, only 1.5% (95% confidence interval: 1.2%–2.0%) were estimated to have taken place in WATSAN-safe conditions. 74% of all health facilities conducted deliveries. Among these, only 44% of facilities overall and 24% of facility delivery rooms were WATSAN-safe. Combining the estimates, we showed that 30.5% of all births in Tanzania took place in a WATSAN-safe environment (range of uncertainty 25%–42%). Large wealth-based inequalities existed in the proportion of births occurring in domestic environments based on wealth quintile and geographical zone. Conclusion Existing data sources can be useful in national monitoring and prioritisation of interventions to improve poor WATSAN environments during childbirth. However, a better conceptual understanding of potentially harmful exposures and better data are needed in order to devise and apply more empirical definitions of WATSAN-safe environments, both at home and in facilities. PMID:25191753

Benova, Lenka; Cumming, Oliver; Gordon, Bruce A.; Magoma, Moke; Campbell, Oona M. R.

2014-01-01

179

Developing operational strategies for the Fort Benning shallow solar pond domestic water heating system  

SciTech Connect

Performance tests were conducted on six of the eighty individual solar ponds that comprise the Fort Benning Shallow Solar Pond Domestic Water Heating System. The system was originally designed to operate at a 3-inch pond fill and provide 500,000 gallons of heated water daily to a laundry and barracks buildings. Since construction, hot water needs from the system have decreased approximately 50% and the original operating strategy was no longer thought to be optimum for current conditions. New operating strategies were tested that could potentially improve system performance. Specifically, these involved varying pond fill levels from 2 to 4 inches and exposure periods from 1 to 3 days. Lower pond fills were found to increase final water temperatures for all exposures. At a 1-day exposure, lowering pond fill from 3 to 2 inches increased pond performance (Btu/gal) by 30%. A larger reduction from 4 to 2 inches produced an approximate 62% increase. With hot water demand on the Fort Benning system well below capacity, lowering pond fill is an excellent option for an immediate and significant performance improvement. Although increasing exposure increased final water temperatures in all but one test case, lowering pond fill was more productive. An individual pond operating at a 3-inch fill and a 1-day exposure collects around 488 MBtu annually which is equivalent to around $4500 in avoided fuel costs. With excess capacity, only the water utilized is saving energy. Therefore, the key operating objective for Fort Benning is to add the most energy possible to the water that is used. Pond fills at Fort Benning should be reduced to 2 inches and exposures should remain at 1 day (unless more ponds are activated). This should provide an immediate increase in pond performance of approximately 30%. 5 refs., 27 figs., 4 tabs.

Sharp, T.R.

1990-06-01

180

Microbiological evaluation of water quality from urban watersheds for domestic water supply improvement  

Technology Transfer Automated Retrieval System (TEKTRAN)

Agricultural and urban runoffs may be major sources of pollution of water bodies and major sources of bacteria affecting the quality of drinking water. Of the different pathways by which bacterial pathogens can enter drinking water, one has received little attention to date; that is, because soils ...

181

Zinc in the sediments, water and biota of Lake Burley Griffin, Canberra  

E-print Network

HI 235 Zinc in the sediments, water and biota of Lake Burley Griffin, Canberra W.A. Maher, RResearchCentre. Universityo/Canberra. P.O. Box /. BelconnenACT 26/6. Australia ABSTRAcr Zinc concentrations and total amounts in the sediment, water and biota of Lake Burley Griffin were measured to identify where zinc originating from

Canberra, University of

182

Trace metal concentrations in water, sediments and fish tissue from Lake Tanganyika  

Microsoft Academic Search

Trace metal (Cu, Pb, Fe, Mn, Zn, Cd) concentrations were determined in water, sediments, various fin fish species and a bivalve (Mutelaspekei) from Lake Tanganyika using an atomic absorption spectrophotometer. Integrated water samples to depths of 10 m were collected using a pre-rinsed flexible plastic pipe. Sediment samples were collected using a ponar mud sampler. Fish samples were obtained using

F. M. M. Chale

2002-01-01

183

Petroleum hydrocarbons in water and sediments of northwest Arabian Gulf 1980–2005  

Microsoft Academic Search

A survey has been conducted to evaluate pollution by petroleum hydrocarbons (PHC's) in water, sediments and living organisms of southern Iraqi sectors represented by Shatt Al-Arab River, Khor Al-Zubair, Umm Qasser, Khor Abdullah and the northwest Arabian Gulf. Petroleum hydrocarbons in water as dissolved and particulate, in sediments as exchangeable and residual and in the organs of living organisms were

Faris J. M. Al-Imarah; Abass A. Hantoosh; Ali M. Nasir

2007-01-01

184

Seasonal Water Discharge and Sediment Load Changes in the Upper Yangtze, China  

Microsoft Academic Search

Analysis of seasonal water discharge and sediment load data for major tributaries of the Upper Yangtze indicates significant changes from 1957 to 1987. Discrimination between land use-induced and climatic variation-induced changes was attempted using the systematic shift in the seasonal sediment load relative to the seasonal water flow. Available evidence suggests that most of these changes were caused by human

Xi Xi Lu; Peter Ashmore; Jin Fei Wang

2003-01-01

185

Recent changes of water discharge and sediment load in the Zhujiang (Pearl River) Basin, China  

Microsoft Academic Search

The paper is concerned with identifying changes in the time series of water and sediment discharge of the Zhujiang (Pearl River), China. The gradual trend test (Mann–Kendall test), and abrupt change test (Pettitt test), have been employed on annual water discharge and sediment load series (from the 1950s–2004) at nine stations in the main channels and main tributaries of the

Shurong Zhang; Xi Xi Lu; David L. Higgitt; Chen-Tung Arthur Chen; Jingtai Han; Huiguo Sun

2008-01-01

186

Sediment Inventory and Phosphorus Fractions for Water Conservation Area Canals in the Everglades  

E-print Network

Sediment Inventory and Phosphorus Fractions for Water Conservation Area Canals in the Everglades O in the Water Conservation Area (WCA) canals in the Ever- glades. A study was conducted to characterize

Florida, University of

187

Suspended sediment control and water quality conservation through riparian vegetation:  

NASA Astrophysics Data System (ADS)

Soil erosion and Suspended Sediment River are strongly related in the Apennines catchments which are generally characterised by a clayey lithology and impermeable soils and extensive and severe erosion and slope stability problems. In fact the suspended sediment yield represents one of the most reliable tools to assess real basin soil loss (Pavanelli and Pagliarani, 2002; Pavanelli and Rigotti, 2007) from the surface rain erosive features in a mountain watershed, as rills and interrills erosion, gullies, bad-lands (calanchi basins). Suspended sediment yield is known to imply several detrimental consequences: soil losses from agricultural land, worsening of the quality of the water, clogging of water supply filters and reservoir siltation. In addition, suspended sediment yield is also one of the main vector for pollutants and nutrients: various studies have already proved how nitrogen content has been constantly rising in aquifers and surface waters [Böhlke and Denver, 1995]. Finer particles and their aggregates have been proved to be the preferential vehicle for particulate nitrogen [Droppo et al., 1997; Ongley et al., 1992]. In one research [Pavanelli and al. 2006] four Apennines torrents (Gaiana, Sillaro, Savena and Lavino) with mountain basins ranging from 8.7 to 139 Km2 were monitored via automatic sampling devices, the samples of water collected were analysed to characterise suspended solids in terms of their grain size distribution and total nitrogen with respect to the source of eroded area in the catchment. Preliminary results [Pavanelli and al. 2007] seem to show the existence of a direct relationship between nitrogen concentration and finer particle concentration (<20 ?m), with the maximum nitrogen loss values being related to factors like the presence of clayey formations, their position within the catchment and the availability of suspended particles. The results seem to indicate hillsides as main sources of suspended sediment to the torrents monitored. The problem of controlling the river suspended sediment concentration can be tackled by increasing the riparian vegetation able to hold back the ground eroded by the slopes, but it is necessary to know where the critical zones are. The aim of the work is to propose a method allow us to detect the risk of soil erosion areas near the river and the functionality of existing riparian vegetation along river as buffers / filters towards the eroded soil from the hill slopes. The proposed methodology is supposed has been designed for water pollution control from suspended solids, pollutants and nutrients coming from hills and an improvement of the quality of the river environment. The methodology was applied on the riparian vegetation of the Gaiana torrent where it was related to soil cover and erosion areas of the hillslope, thus correlating the impact of human activities. The Gaiana catchment area is 8.6 km2 and the mean altitude is 237 a.m.s.l., the average rainfall is of 784 mm.. It is a typical Apennines streams, about 35 km south of Bologna, Italy. The main trunk stream is 6 km long and the whole drainage network is organized in a dendritic pattern, typical of clayey lithology of the basins. The main erosion processes active in the area are caused by precipitation and surface runoff: sheet wash, concentrated water erosion and badlands watersheds (calanchi), which represent about 15% of the basin area. The vegetation of the Gaiana basin is constituted by crops (39%), woods (37%), rock outcrops(i.e. badlands)(15%), bushes (5%) and pastures(3%). The stages of the study are to spot critical areas made up of streambank and the eroded areas on the slopes near the river, with the support of aerial photos and satellite images, survey and a geographic information system. The Gaiana riparian vegetation map has been drawn and, on a strip buffer 200 metres wide along river, the Vegetation cover and the Geomorphology maps (scale 1:5000) has been drawn, after photogrammetric interpretation of aerial photography and satellite images . The two maps have been overlapped to

Pavanelli, D.; Cavazza, C.; Correggiari, S.

2009-04-01

188

Sedimentation and water quality in the West Branch Shade River basin, Ohio, 1984 water year  

USGS Publications Warehouse

Sedimentation in, and flooding of, the West Branch Shade River and its tributaries have been major concerns of residents and State and local officials. The area was extensively surface mined for coal between the mid-1940 's and the early 1960's. Reclamation efforts immediately after mining were unsuccessful. The results have been elevated sediment loads and the subsequent loss of channel conveyance. Two sediment and stream gaging stations were established on West Branch Shade River in the area of past mining to provide data to evaluate the effectiveness of current reclamation activities on reducing sediment loads. A third station was established on the East Branch Shade River in an unmined area as a control. From October 1983 through September 1984, the annual suspended sediment yield/acre-ft of runoff was approximately two times as high for West Branch Shade River (0.51 ton/acre-ft of runoff) as for East Branch Shade River (0.28 ton/acre-ft). In addition, water quality of West Branch indicates that acidity is higher, pH is lower, and concentrations of dissolved sulfate and metals are higher than for East Branch. The concentration of coal in bed material increased in the downstream direction along West Branch Shade River. The concentration downstream in the West Branch was more than 20 times greater than in the East Branch. (Author 's abstract)

Childress, C.J.; Jones, R.L.

1985-01-01

189

Immobilization of phosphorus from water and sediment using zirconium-modified zeolites.  

PubMed

Adding sorbents to sediments has been suggested as an effective technology for contaminated sediment remediation. In this study, a zirconium-modified zeolite (ZrMZ) was prepared, characterized, and used as a sediment amendment to control phosphorus (P) release from eutrophic lake sediments. The efficiency of ZrMZ in immobilizing P from water and sediments was investigated through a series of experiments. The phosphate adsorption capacity for ZrMZ decreased with increasing water pH. The adsorption of phosphate on ZrMZ followed a pseudo-second-order kinetic model. The equilibrium adsorption data of phosphate on ZrMZ could be well described by the Langmuir isotherm model with a maximum monolayer adsorption capacity of 10.2 mg P/g at pH 7 and 25 °C. Sequential extraction of P from the phosphate-adsorbed ZrMZ suggested that most of P bound by ZrMZ existed as the NaOH extractable P (NaOH-P) and residual P (Res-P) and was unlikely to be released under natural pH and reducing conditions. The addition of ZrMZ into sediments reduced the inorganic P activity in the sediments by transforming bicarbonate-dithionite extractable P (BD-P) to NaOH-P and Res-P. The contents of bioavailable P such as water-soluble P (WS-P), NaHCO3 extractable P (Olsen-P), and algal available P (AAP) in sediments reduced after the sediments were mixed with ZrMZ, making P in the sediments more stable. The addition of ZrMZ into sediments significantly reduced the releasing flux of P from the sediments to the water column under different conditions. Results of this study indicate that the ZrMZ is a promising sediment amendment for controlling the internal P loading of lake sediments. PMID:25253056

Yang, Mengjuan; Lin, Jianwei; Zhan, Yanhui; Zhu, Zhiliang; Zhang, Honghua

2015-03-01

190

Bacterial magnetite produced in water column dominates lake sediment mineral magnetism: Lake Ely, USA  

NASA Astrophysics Data System (ADS)

Environmental magnetic studies of annually laminated sediments from Lake Ely, northeastern Pennsylvania, USA indicate that bacterial magnetite is the dominant magnetic mineral in the lake sediment. In previous studies of Lake Ely sediment, the dark, organic-rich layers in the annual laminae were interpreted to have high-intensity saturation isothermal remanent magnetizations (SIRMs) while the light-coloured, silt-rich layers have low-intensity SIRMs. To test the hypothesis that the magnetic grains in the sediments were an authigenic product of magnetotactic bacteria rather than detrital magnetic grains eroded from the watershed, we analysed samples from the water column, the lake sediment, and a sediment trap installed near the lake bottom. Direct microscopic observation of the water column samples showed the presence of magnetotactic bacteria in and below the oxic-anoxic transition zone (OATZ). To characterize the magnetic minerals, rock magnetic parameters were measured for material from the water column, the sediment trap and the dark- and light-coloured lake sediments. Low-temperature magnetic measurements tested for the presence of magnetosomes in separated dark- and light-coloured layer samples. Numeric unmixing of the low-temperature results showed that biogenic magnetites were present in the lake sediment and contributed more significantly to the SIRM in the dark, organic-rich layers than in the light-coloured, inorganic silt-rich layers. Observations under the transmission electron microscope (TEM) of magnetic extracts also show the abundance of magnetosomes in the lake sediment. The presence of live magnetotactic bacteria in the water column and the predominance of bacterial magnetites in filtered particulate matter, sediment traps and recent lake sediment all suggest that bacterial magnetites are the main magnetic minerals in Lake Ely sediment. This finding suggests that changes in environmental factors that control the productivity of magnetic bacteria in the lake likely contribute to the variability of magnetic mineral concentrations observed in the lake sediments.

Kim, BangYeon; Kodama, Kenneth P.; Moeller, Robert E.

2005-10-01

191

Analysis of space heating and domestic hot water systems for energy-efficient residential buildings  

SciTech Connect

An analysis of the best ways of meeting the space heating and domestic hot water (DHW) needs of new energy-efficient houses with very low requirements for space heat is provided. The DHW load is about equal to the space heating load in such houses in northern climates. The equipment options which should be considered are discussed, including new equipment recently introduced in the market. It is concluded that the first consideration in selecting systems for energy-efficient houses should be identification of the air moving needs of the house for heat distribution, heat storage, ventilation, and ventilative cooling. This is followed, in order, by selection of the most appropriate distribution system, the heating appliances and controls, and the preferred energy source, gas, oil, or electricity.

Dennehy, G

1983-04-01

192

Applying Ra isotopes to measure water exchange rates in permeable sediments  

NASA Astrophysics Data System (ADS)

In the coastal ocean, waves and currents generate pressure gradients at the seafloor, which drive a circulation of seawater through sandy seafloor sediments. Biological activity in the sediments converts inflowing organic matter and oxidants into CO2 and nutrients, which are returned to the water column. To evaluate the impact of benthic organic matter cycling on ocean chemistry, the fluid flow rate through permeable sediments must be known. At Huntington Beach, CA, between the shoreline and 3 km offshore, we have collected sediment cores and in situ pore waters. Samples were analyzed for oxygen, nutrients, and four naturally-occurring radioisotopes: 222Rn, 223Ra, 224Ra, and 228Ra. We have calculated fluid circulation rates within sediments using a reaction- transport model of the radioisotope pore water distributions. Pore waters in the top 25-55 cm of sediments were flushed every 4-10 days. 228Ra profiles identified slower exchange that occurred deeper in the sediments. Dissolved 228Ra increased with depth in sediments and accounted for a significant fraction of the pore water 224Ra. The resulting 224Ra emanation gradient must be included in models to accurately calculate the irrigation rate. 223Ra profiles were similar to 224Ra profiles, suggesting a similar relationship with 227Ac. The irrigation rate can then be applied to the pore water distribution of nutrients to calculate the flux of nutrients returned to the water column and estimate the supply of organic carbon to the seafloor.

Colbert, S. L.; Hammond, D. E.

2007-12-01

193

Processing of combined domestic bath and laundry waste waters for reuse as commode flushing water  

NASA Technical Reports Server (NTRS)

An experimental investigation of processes and system configurations for reclaiming combined bath and laundry waste waters for reuse as commode flush water was conducted. A 90-min recycle flow was effective in removing particulates and in improving other physical characteristics to the extent that the filtered water was subjectively acceptable for reuse. The addition of a charcoal filter resulted in noticeable improvements in color, turbidity, and suds elimination. Heating and chlorination of the waste waters were investigated for reducing total organism counts and eliminating coliform organisms. A temperature of 335.9 K (145 F) for 30 min and chlorine concentrations of 20 mg/l in the collection tank followed by 10 mg/l in the storage tank were determined to be adequate for this purpose. Water volume relationships and energy-use rates for the waste water reuse systems are also discussed.

Hypes, W. D.; Batten, C. E.; Wilkins, J. R.

1975-01-01

194

Sediment Enzyme Activities and Microbial Community Diversity in an Oligotrophic Drinking Water Reservoir, Eastern China  

PubMed Central

Drinking water reservoir plays a vital role in the security of urban water supply, yet little is known about microbial community diversity harbored in the sediment of this oligotrophic freshwater environmental ecosystem. In the present study, integrating community level physiological profiles (CLPPs), nested polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) and clone sequence technologies, we examined the sediment urease and protease activities, bacterial community functional diversity, genetic diversity of bacterial and fungal communities in sediments from six sampling sites of Zhou cun drinking water reservoir, eastern China. The results showed that sediment urease activity was markedly distinct along the sites, ranged from 2.48 to 11.81 mg NH3-N/(g·24h). The highest average well color development (AWCD) was found in site C, indicating the highest metabolic activity of heterotrophic bacterial community. Principal component analysis (PCA) revealed tremendous differences in the functional (metabolic) diversity patterns of the sediment bacterial communities from different sites. Meanwhile, DGGE fingerprints also indicated spatial changes of genetic diversity of sediment bacterial and fungal communities. The sequence BLAST analysis of all the sediment samples found that Comamonas sp. was the dominant bacterial species harbored in site A. Alternaria alternate, Allomyces macrogynus and Rhizophydium sp. were most commonly detected fungal species in sediments of the Zhou cun drinking water reservoir. The results from this work provide new insights about the heterogeneity of sediment microbial community metabolic activity and genetic diversity in the oligotrophic drinking water reservoir. PMID:24205265

Zhang, Haihan; Huang, Tinglin; Liu, Tingting

2013-01-01

195

AN ASSESSMENT OF USING WATER RECYCLING TO RELEASE WATER FOR NEW DOMESTIC CONSUMERS: INITIAL RESULTS  

Microsoft Academic Search

One of the benefits of recycling water to industry is the opportunity to free existing potable water supplies for new customers. A recycling plant was commissioned in May 2001 in Merebank, Durban. The plant receives effluent from the Durban Southern Wastewater Treatment works and treats it to an acceptable standard for industrial use. However, as with any industrial activity there

S. D. Pillay; E. Friedrich; C. A. Buckley

196

Field Observations of Hydrodynamics, Sediment Transport, and Water and Sediment Quality in the Hudson-Raritan Estuary  

NASA Astrophysics Data System (ADS)

The New York-New Jersey Harbor estuary system is of enormous ecological and economic importance to the region. The presence of toxic chemicals in the water and sediments results in reduced water quality, fisheries restrictions/advisories, and general adverse impacts to the estuarine ecosystem. The Port of New York and New Jersey is central to the economy of the region. However, in recent years, problems associated with the management of contaminated dredged material, including high costs and the lack of suitable disposal/use alternatives, have threatened to impact the volume of shipping in the Harbor. Sources of contaminants include atmospheric deposition, municipal and industrial wastewater treatment facilities, combined sewer and stormwater outfalls, and rainfall-induced runoff (non-point sources). In addition, Harbor sediments can act as a continuing source as they are re-suspended and moved throughout the system by both natural and man-made means. As part of the New Jersey Toxics Reduction Workplan, Stevens Institute of Technology and Rutgers University are conducting hydrodynamic, sediment transport, and water and suspended sediment quality measurements in Newark Bay, the Arthur Kill and the Kill van Kull. The goals of the project include: (1) collection of high resolution (event-driven and long-term) hydrodynamic, sediment transport and water and suspended sediment quality measurements for use in the assessment of the dominant physics of the system and in the development of a combined hydrodynamic-sediment transport-water/sediment quality model for the region. (2) identification of those tributaries to NY-NJ Harbor that are significant sources of the chemicals of concern, and evaluation of the importance of non-point sources and existing contaminated bottom sediments as sources of the chemicals of concern. (3) identification of point discharges that represent significant sources of the chemicals of concern. Observations were obtained over a two-year period, during 21 tributary flow "events", each having an approximate duration of 1 week. The measurement program included 3 fixed mooring stations and 5 shipboard locations. Each mooring consisted of an acoustic Doppler current profiler; a high-resolution pressure sensor; an OBS; a CTD; and a laser-based scatterometer. The ship-board measurements included vertical current profiles using a towed acoustic Doppler current profiler; CTD measurements; OBS measurements; suspended sediment concentration and particle size spectrum using a laser-based scatterometer; and chemical characterization of water and suspended sediment samples. The water and sediment quality measurements were obtained using a specially designed Trace Organics Platform Sampler. This sampler allowed for the measurement of low-level concentrations of PCBs (108 congeners), dioxins/furans, Pesticides, PAHs and metals (Hg, Cd, Pb). Preliminary analysis of the data has improved our understanding of the circulation and sediment transport patterns in this region of the estuary, including the influence of extreme tributary flow events, local winds, and anthropogenic effects such as port structures, vessels, and the navigation channels, and has identified the most highly contaminated reaches of the tributaries.

Bruno, M. S.; Glenn, S.; Chant, R.; Rankin, K.; Korfiatis, G.; Dimou, N.; Creed, E.; Fullerton, B.; Pence, A.; Burke, P.; Haldeman, C.; Hires, R.; Hunter, E.

2002-12-01

197

Control of water erosion and sediment in open cut coal mines in tropical areas  

SciTech Connect

The purpose is to reduce the environmental impacts from open cut mining in tropical areas, such as Indonesia and Vietnam. Research conducted on methods for the control of water erosion and sediment from open cut coal mines is described. Data were collected on climate and weathering in tropical areas, mechanism of water erosion and sedimentation, characteristics of rocks in coal measures under wet conditions, water management at pits and haul roads and ramps, and construction of waste dumps and water management. The results will be applied to the optimum control and management of erosion and sediments in open cut mining. 6 refs., 8 figs.

Ueda, T.; Nugraha, C.; Matsui, K.; Shimada, H.; Ichinose, M.; Gottfried, J. [Kyushu University, Fukuoka (Japan). Department of Earth Resources Engineering

2005-07-01

198

Investigation of magnetotaxis of magnetotactic bacteria in water and sediment  

NASA Astrophysics Data System (ADS)

Magnetotactic bacteria contain chains of magnetic particles which allow them to align and move along the magnetic field to search for optimal habitats in chemically stratified environments. This phenomenon is known as magnetotaxis. The alignment is passive, and driven by the torque m-B between the magnetic dipole m of the chain and the external magnetic field B. The alignment is counteracted by the randomizing effect of Brownian motion, and the average alignment of free bacteria in water, expressed by cos(?), where ? is the angle between m and B, is expected to follow the Langevin law cos(?) = L(mB/kT) where k is the Boltzmann constant and T the absolute temperature [Frankel, 1980]. This law implies that a minimum strength for the Earth's field is required for a bacterium with given magnetic moment to have a certain alignment with the field. The resulting motion is a biased random walk whose "efficiency" for a displacement along B is equal to the average aligmnent. Calculated values for cos(?) in the present Earth's field give good alignments >0.9. Direct experimental observations of the Langevin law on living bacteria in various field intensity are limited to one study by [Kalmijn, 1981]. Here we report systematic observations for two types of wild-type bacteria: magnetic cocci containing two to five chains of ~100 magnetosomes, and magnetobacterium Bavaricum , a rod-shaped bacterium containing several hundreds magnetosomes [Hanzlik et al., 1996]. We also investigated the aligment of those bacteria in natural sediment, where physical constraints imposed by the pore volume are expected to have a great influence on their capability of to align with an external field. Our results show that the alignment of free swimming magnetotactic bacteria in water obeys Langevin's law, with >0.8 alignments in external fields of 3?T for Bavaricum and 30?T for big cocci (the present earth's field is at avrage 50?T). This result shows that magnetotactic bacteria, and in particular Bavaricum, synthesize more than 10 times magnetosomes than they need for magnetotaxis in present field. This fact could leat to the suggestion that magnetosomes could have other unknown functions besides navigation in a magnetic field. On the other hand, typical sedimentary environments pose drastically different conditions for magnetotaxis. This is shown by our measurements of bacteria's alignment in acquaria containing natural lake sediments. Because direct observation of bacteria in sediment is not possible, we applied strong pulsed magnetic field to reverse the magnetic moment of bacteria whose magnetic moment forms a >90° angle to the pulse field. These bacteria become South-seeking and can be counted. By applying pulses along different directions with respect to the external field it is possible to calculate their alignment from the ratio between North- and South seeking. Our results indicate that the bacteria's alignment in sediment is

Mao, X.; Egli, R.

2012-04-01

199

The potential source of dissolved aluminum from resuspended sediments to the North Atlantic deep water  

SciTech Connect

Laboratory and field studies were conducted to investigate the significance of resuspended sediments as a source of dissolved Al to the deep northwest Atlantic. Sediment resuspension experiments demonstrate the effect on dissolved Al concentration (initially 11 nM) of adding natural suspended sediments (ca. 0.1-10 mg/L) to seawater. The concentration of dissolved Al increased by the resuspension of sediments; for example, addition of 0.15 mg/L sediments caused dissolved Al to increase by 10 nM. Distributions of dissolved and leachable particulate Al off the tail of the Grand Banks, near the high-energy western boundary current, show elevated levels in the near-bottom waters. The authors suggest that resuspended sediments associated with nepheloid layers along the western boundary of the North Atlantic are a source of dissolved Al. Strong western boundary currents provide the energy to resuspend and maintain intense nepheloid layers of sediments. Continued resuspension and deposition of sediments within the nepheloid layer promotes the release of Al from sediments to the overlying water. The Al-rich terrigenous sediments that predominate along the deep boundary of the Denmark Strait, Labrador Sea, Newfoundland and off Nova Scotia constitute a potentially significant source of dissolved Al. Release of Al from resuspended sediments associated with nepheloid layers at a more northern location (e.g., Denmark Strait) may contribute to the near-linear increase in dissolved Al with depth observed in the deep northwest Atlantic.

Moran, S.B.; Moore, R.M. (Dalhousie Univ., Halifax, Nova Scotia (Canada))

1991-10-01

200

Ecological impacts of lead mining on Ozark streams: Toxicity of sediment and pore water  

USGS Publications Warehouse

We studied the toxicity of sediments downstream of lead-zinc mining areas in southeast Missouri, using chronic sediment toxicity tests with the amphipod, Hyalella azteca, and pore-water toxicity tests with the daphnid, Ceriodaphnia dubia. Tests conducted in 2002 documented reduced survival of amphipods in stream sediments collected near mining areas and reduced survival and reproduction of daphnids in most pore waters tested. Additional amphipod tests conducted in 2004 documented significant toxic effects of sediments from three streams downstream of mining areas: Strother Creek, West Fork Black River, and Bee Fork. Greatest toxicity occurred in sediments from a 6-km reach of upper Strother Creek, but significant toxic effects occurred in sediments collected at least 14 km downstream of mining in all three watersheds. Toxic effects were significantly correlated with metal concentrations (nickel, zinc, cadmium, and lead) in sediments and pore waters and were generally consistent with predictions of metal toxicity risks based on sediment quality guidelines, although ammonia and manganese may also have contributed to toxicity at a few sites. Responses of amphipods in sediment toxicity tests were significantly correlated with characteristics of benthic invertebrate communities in study streams. These results indicate that toxicity of metals associated with sediments contributes to adverse ecological effects in streams draining the Viburnum Trend mining district.

Besser, J.M.; Brumbaugh, W.G.; Allert, A.L.; Poulton, B.C.; Schmitt, C.J.; Ingersoll, C.G.

2009-01-01

201

Ecological impacts of lead mining on Ozark streams: toxicity of sediment and pore water.  

PubMed

We studied the toxicity of sediments downstream of lead-zinc mining areas in southeast Missouri, using chronic sediment toxicity tests with the amphipod, Hyalella azteca, and pore-water toxicity tests with the daphnid, Ceriodaphnia dubia. Tests conducted in 2002 documented reduced survival of amphipods in stream sediments collected near mining areas and reduced survival and reproduction of daphnids in most pore waters tested. Additional amphipod tests conducted in 2004 documented significant toxic effects of sediments from three streams downstream of mining areas: Strother Creek, West Fork Black River, and Bee Fork. Greatest toxicity occurred in sediments from a 6-km reach of upper Strother Creek, but significant toxic effects occurred in sediments collected at least 14 km downstream of mining in all three watersheds. Toxic effects were significantly correlated with metal concentrations (nickel, zinc, cadmium, and lead) in sediments and pore waters and were generally consistent with predictions of metal toxicity risks based on sediment quality guidelines, although ammonia and manganese may also have contributed to toxicity at a few sites. Responses of amphipods in sediment toxicity tests were significantly correlated with characteristics of benthic invertebrate communities in study streams. These results indicate that toxicity of metals associated with sediments contributes to adverse ecological effects in streams draining the Viburnum Trend mining district. PMID:18603298

Besser, John M; Brumbaugh, William G; Allert, Ann L; Poulton, Barry C; Schmitt, Christopher J; Ingersoll, Christopher G

2009-02-01

202

Chemistry of calcium carbonate-rich shallow water sediments in the Bahamas  

SciTech Connect

The geochemistry of calcium carbonate-rich sediments from a variety of environments throughout the Bahamas was investigated with particular emphasis on the factors that control the pore water chemistry. Most sediments are supersaturated with respect to aragonite, the most abundant carbonate component. Experimental studies indicate that the observed in situ calcium carbonate ion activity products can often be produced as reversible metastable equilibria between the sediments and seawater. This is interpreted as being the result of interactions between the solutions and the minor high Mg-calcite component present in these sediments. Although the overlying waters are more supersaturated than the pore waters, carbonate dissolution, not precipitation, dominates in these sediments as a result of organic matter oxidation and the resulting increase in P/sub CO/sub 2//. The carbonate sediments of the Bahamas are remarkable for their purity, with the exception of special environments such as mangrove swamps and tidal flats with algal mats. Organic matter and heavy metal content is extremely low. Only minor sulfate reduction is occurring in most sediments. Phosphate is undetectable in all pore waters, probably as a result of adsorption on carbonate mineral surfaces. Other dissolved pore water components such as ammonia and DOC are much lower than typically found in shallow water fine-grained terrigeneous sediments.

Morse, J.W.; Zullig, J.J.; Bernstein, L.D.; Millero, F.J.; Milne, P.; Mucci, A.; Choppin, G.R.

1985-02-01

203

Anthropogenic effects on global riverine sediment and water discharge - a spatially explicit analysis  

NASA Astrophysics Data System (ADS)

Changes in global riverine water discharge and suspended sediment flux over a 50-year period, 1960-2010 are studied, applying a new version of the WBMsed (WBMsed v.2.0) global hydrological water balance model. A new floodplain component is introduced to better represent water and sediment dynamics during periods of overbank discharge. Validated against data from 16 globally distributed stations, WBMsed v.2.0 simulation results show considerable improvement over the original model. Anthropogenic impact on sediment and water discharge is evaluated by comparing global scale simulations with and without human drivers and parameters (agricultural land use, water intake form aquifers and rivers, sediment trapping in reservoirs, and human-induced soil erosion). The results show that, on average, global riverine sediment flux is reduced by approximately 25% by anthropogenic activities (almost exclusively due to trapping in reservoirs) while water discharge is reduced by about 2%. These results correspond to previous analysis by other research groups. Substantial global and intra-basin variability is observed (see Figure 1) for the first time. In some regions an opposite anthropogenic effect on sediment and water discharge was predicted (e.g. west Mississippi Basin, Rio Grande River, Indian subcontinent). We discuss the western part of the Mississippi Basin as an example of this intriguing anthropogenic impact. Figure 1. Percent change between disturbed and pristine simulations (with and without human footprint respectively) for sediment flux (top) and water discharge (bottom).

Cohen, S.; Kettner, A. J.; Syvitski, J. P.

2013-12-01

204

Levels of PAHs in the Waters, Sediments, and Shrimps of Estero de Urias, an Estuary in Mexico, and Their Toxicological Effects  

PubMed Central

PAHs were measured in water, sediment, and shrimps of Estero de Urias, an estuary in Sinaloa, Mexico, during the rainy and dry seasons, and analyzed for eleven PAHs routinely detected in samples. Phenanthrene was the most dominant congener in the water, sediment, and shrimp samples comprising about 38, 24, and 25%, respectively, of the eleven PAHs detected, followed by pyrene and naphthalene in water and sediment samples, and pyrene and fluorine in the shrimp samples. Total PAH concentrations ranged from 9 to 347?ng/L in water, 27 to 418?ng/g in sediments, and 36 to 498?ng/g in shrimps. The sources of contamination are closely related to human activities such as domestic and industrial discharge, automobile exhausts, and street runoff. High concentrations were also measured during the rainy season and during the first quarter of the year. Toxicity tests were also carried out, exposing fish embryos and juvenile shrimps to some of these PAHs. Fish embryos exposed to PAHs showed exogastrulation, while juvenile shrimps showed significantly lower growth rates than controls. DNA and protein alterations were also observed. These toxicity tests indicate that PAH concentrations measured could be dangerous to some aquatic organisms, particularly during early stages of development. PMID:22997501

Jaward, Foday M.; Alegria, Henry A.; Galindo Reyes, Jose G.; Hoare, Armando

2012-01-01

205

MANAVGAT RIVER WATER AS A LIMITED BUT ALTERNATIVE WATER RESOURCE FOR DOMESTIC USE IN MIDDLE EAST  

Microsoft Academic Search

The water potential of the Mediterranean part including Aegen coastal zone of Turkey is at a level of mean annual about 8.2 x 109 m3. The size of irrigable land, in this part of the country is about 1.8x106 ha, and there is very high tourism potential in the region. The main water courses along Mediterrenean coast of Turkey, from

Mehmet Ülger

206

Evaluation of the MULTISED (Multiple Watershed Storm Water and Sediment Runoff Simulation) simulation model to predict sediment yield. Final report  

Microsoft Academic Search

The MULTISED (Multiple Watershed Storm Water and Sediment Runoff Simulation) model was evaluated as a tool that will help Army land managers assess the environmental conditions of troop training areas to determine the need for remedial action. The sensitivity of model parameters was explored using two watersheds. Guidelines for calibrating the model were developed, based on a best-fit criterion between

H. G. Wenzel; C. S. Melching

1987-01-01

207

Water permeability in hydrate-bearing sediments: A pore-scale study  

NASA Astrophysics Data System (ADS)

Permeability is a critical parameter governing methane flux and fluid flow in hydrate-bearing sediments; however, limited valid data are available due to experimental challenges. Here we investigate the relationship between apparent water permeability (k') and hydrate saturation (Sh), accounting for hydrate pore-scale growth habit and meso-scale heterogeneity. Results from capillary tube models rely on cross-sectional tube shapes and hydrate pore habits, thus are appropriate only for sediments with uniform hydrate distribution and known hydrate pore character. Given our pore network modeling results showing that accumulating hydrate in sediments decreases sediment porosity and increases hydraulic tortuosity, we propose a modified Kozeny-Carman model to characterize water permeability in hydrate-bearing sediments. This model agrees well with experimental results and can be easily implemented in reservoir simulators with no empirical variables other than Sh. Results are also relevant to flow through other natural sediments that undergo diagenesis, salt precipitation, or bio-clogging.

Dai, Sheng; Seol, Yongkoo

2014-06-01

208

Parameterization of biogeochemical sediment-water fluxes using in-situ measurements and a steady-state diagenetic model  

NASA Astrophysics Data System (ADS)

Sediment biogeochemical processes are important drivers of water column biogeochemistry in coastal areas. For example, sediment oxygen consumption can be an important driver of bottom water oxygen depletion in hypoxic systems, and sediment-water nutrient fluxes support primary productivity in the overlying water column. Yet, biogeochemical sediment-water fluxes are often parameterized crudely and only poorly constrained in coupled physical-biogeochemical models. Here, we present a method for parameterizing biogeochemical sediment-water fluxes realistically and efficiently, using in-situ measurements and a steady state diagenetic model. We apply this method to the Louisiana Shelf where high primary production induced by excess nutrient loads from the Mississippi-Atchafalaya River system promotes the development of hypoxic bottom waters in summer. The implementation of the parameterizations in a coupled circulation-biogeochemical model of the northern Gulf of Mexico results in realistic sediment-water fluxes that enable a sediment-water column feedback at low bottom oxygen concentrations.

Laurent, Arnaud; Fennel, Katja; Wilson, Robin; Lehrter, John; Devereux, Richard

2014-05-01

209

An investigation of the effects of water velocity on inorganic phosphorus influx to a sediment  

Microsoft Academic Search

Measurements of the net influx of soluble reactive phosphorus (SRP), to a river bed-sediment, illustrate the importance of the water velocity and hydrodynamics in controlling the transfer rates. Experiments are reported using a characterised bed-sediment, with associated fauna, contained in a flowing-water channel. The results show a systematic increase in the net influx of SRP with increasing water velocity.A mathematical

W. A. House; F. H. Denison; J. T. Smith; P. D. Armitage

1995-01-01

210

Nutrient and sediment removal in forested wetlands receiving pumped agricultural drainage water  

Microsoft Academic Search

The effectiveness of two forested wetland buffer areas at removing sediment and nutrients from pumped agricultural drainage\\u000a water was evaluated in a two-year field study. The movement of these potential pollutants during pumping events was determined\\u000a by sampling water quality at 36 stations distributed over each wetland. Automatic water sampling continued after pumping events\\u000a to determine the nutrient and sediment

G. M. Chescheir; J. W. Gilliam; R. W. Skaggs; R. G. Broadhead

1991-01-01

211

Uptake rates of semipermeable membrane devices (SPMDs) for PCDDs, PCDFs and PCBs in water and sediment  

Microsoft Academic Search

Uptake rates of several PCDDs, PCDFs and PCBs were measured for semipermeable membrane devices (SPMDs) under controlled conditions in bulk water and sediment. The study was performed at 19°C and 11°C, and water and sediment concentrations were measured during the exposure. Linear uptake rates for specific PCDD\\/Fs and PCBs in 19°C water varied from 34 to 111 l\\/m2day and in

Anna-Lea Rantalainen; Walter J Cretney; Michael G Ikonomou

2000-01-01

212

A generic method for projecting and valuing domestic water uses, application to the Mediterranean basin at the 2050 horizon.  

NASA Astrophysics Data System (ADS)

The aim is to be able to assess future domestic water demands in a region with heterogeneous levels of economic development. This work offers an original combination of a quantitative projection of demands (similar to WaterGAP methodology) and an estimation of the marginal benefit of water. This method is applicable to different levels of economic development and usable for large-scale hydroeconomic modelling. The global method consists in building demand functions taking into account the impact of both the price of water and the level of equipment, proxied by economic development, on domestic water demand. Our basis is a 3-blocks inverse demand function: the first block consists of essential water requirements for food and hygiene; the second block matches intermediate needs; and the last block corresponds to additional water consumption, such as outdoor uses, which are the least valued. The volume of the first block is fixed to match recommended basic water requirements from the literature, but we assume that the volume limits of blocks 2 and 3 depend on the level of household equipment and therefore evolve with the level of GDP per capita (structural change), with a saturation. For blocks 1 and 2 we determine the value of water from elasticity, price and quantity data from the literature, using the point-extension method. For block 3, we use a hypothetical zero-cost demand and maximal demand with actual water costs to linearly interpolate the inverse demand function. These functions are calibrated on the 24 countries part of the Mediterranean basin using data from SIMEDD, and are used for the projection and valuation of domestic water demands at the 2050 horizon. They enable to project total water demand, and also the respective shares of the different categories of demand (basic demand, intermediate demand and additional uses). These projections are performed under different combined scenarios of population, GDP and water costs.

Neverre, Noémie; Dumas, Patrice

2014-05-01

213

Microbial genotoxicity as an environmental indicator for near-coastal sediment pore waters.  

PubMed

The genotoxic potential of sediment pore water collected from coastal areas in the Gulf of Mexico has not been reported frequently in the literature. This report summarizes a study of the microbial mutagenicity of 31 pore water samples obtained from sediment affected by non-point source runoff and compares the results with those for more traditional chemical and biological indicators of sediment quality. Genotoxicity was determined pre- and post-enzyme activation using a proprietary short-term microbial assay for pore water centrifuged from sediment collected adjacent to a Florida coastal golf complex and from an urbanized bayou-estuary. Sediment and the associated pore water also were analyzed for acute toxicity to Hyallela azteca, Palaemonetes pugio, or Americamysis bahia and for benthic macroinvertebrate diversity (sediment only). Genotoxicity (direct and enzyme-activated) was detected in 4 of 17 (golf complex) and in 10 of 14 (urbanized bayou) pore water samples. The lowest toxic pore water concentrations were between 1.8% and 44.4% (direct) and between 2.6% and 25% (enzyme-activated). The results of the genotoxic assay paralleled those based on exceedance of proposed sediment quality guidelines, pore water acute toxicity and Shannon-Wiener diversity index values for 81%, 58%, and 65% of the comparisons, respectively. PMID:16646015

Lewis, Michael A; Daniels, Carol B; Chancy, Cynthia A

2006-06-01

214

Survival of daphnia magna and hyalella azteca in cadmium-spiked water and sediment  

Microsoft Academic Search

Freshwater sediments and water were spiked with cadmium (Cd) in the laboratory, and toxicity tests were conducted with the cladoceran Daphnia magna and the amphipod Hyalella azteca to determine if Cd in the sediment would cause increased toxicity. The 48-h LC50 values for Daphnia in tests without sediment were 36, 33, 24, and 40 micrograms\\/L total Cd. Calculated free-ion (Cd\\/sup

Alan V. Nebeker; Samuel T. Onjukka; Michael A. Cairns; Daniel F. Krawczyk

1986-01-01

215

Magdalena river: interannual variability (1975–1995) and revised water discharge and sediment load estimates  

Microsoft Academic Search

Magdalena river discharges 228km3 of water annually, or on the average 7200m3s?1, into the western Caribbean based on 21years of daily data, 1975–1995. The mean sediment load for the Magdalena is 144×106tyr?1, corresponding to a sediment yield of 560tkm?2yr?1 for the 257,438km2 basin. Magdalena is the largest river discharging directly into the Caribbean Sea, and it has the highest sediment

J. D Restrepo; B Kjerfve

2000-01-01

216

ECO: a generic eutrophication model including comprehensive sediment-water interaction.  

PubMed

The content and calibration of the comprehensive generic 3D eutrophication model ECO for water and sediment quality is presented. Based on a computational grid for water and sediment, ECO is used as a tool for water quality management to simulate concentrations and mass fluxes of nutrients (N, P, Si), phytoplankton species, detrital organic matter, electron acceptors and related substances. ECO combines integral simulation of water and sediment quality with sediment diagenesis and closed mass balances. Its advanced process formulations for substances in the water column and the bed sediment were developed to allow for a much more dynamic calculation of the sediment-water exchange fluxes of nutrients as resulting from steep concentration gradients across the sediment-water interface than is possible with other eutrophication models. ECO is to more accurately calculate the accumulation of organic matter and nutrients in the sediment, and to allow for more accurate prediction of phytoplankton biomass and water quality in response to mitigative measures such as nutrient load reduction. ECO was calibrated for shallow Lake Veluwe (The Netherlands). Due to restoration measures this lake underwent a transition from hypertrophic conditions to moderately eutrophic conditions, leading to the extensive colonization by submerged macrophytes. ECO reproduces observed water quality well for the transition period of ten years. The values of its process coefficients are in line with ranges derived from literature. ECO's calculation results underline the importance of redox processes and phosphate speciation for the nutrient return fluxes. Among other things, the results suggest that authigenic formation of a stable apatite-like mineral in the sediment can contribute significantly to oligotrophication of a lake after a phosphorus load reduction. PMID:23844160

Smits, Johannes G C; van Beek, Jan K L

2013-01-01

217

ECO: A Generic Eutrophication Model Including Comprehensive Sediment-Water Interaction  

PubMed Central

The content and calibration of the comprehensive generic 3D eutrophication model ECO for water and sediment quality is presented. Based on a computational grid for water and sediment, ECO is used as a tool for water quality management to simulate concentrations and mass fluxes of nutrients (N, P, Si), phytoplankton species, detrital organic matter, electron acceptors and related substances. ECO combines integral simulation of water and sediment quality with sediment diagenesis and closed mass balances. Its advanced process formulations for substances in the water column and the bed sediment were developed to allow for a much more dynamic calculation of the sediment-water exchange fluxes of nutrients as resulting from steep concentration gradients across the sediment-water interface than is possible with other eutrophication models. ECO is to more accurately calculate the accumulation of organic matter and nutrients in the sediment, and to allow for more accurate prediction of phytoplankton biomass and water quality in response to mitigative measures such as nutrient load reduction. ECO was calibrated for shallow Lake Veluwe (The Netherlands). Due to restoration measures this lake underwent a transition from hypertrophic conditions to moderately eutrophic conditions, leading to the extensive colonization by submerged macrophytes. ECO reproduces observed water quality well for the transition period of ten years. The values of its process coefficients are in line with ranges derived from literature. ECO’s calculation results underline the importance of redox processes and phosphate speciation for the nutrient return fluxes. Among other things, the results suggest that authigenic formation of a stable apatite-like mineral in the sediment can contribute significantly to oligotrophication of a lake after a phosphorus load reduction. PMID:23844160

Smits, Johannes G. C.; van Beek, Jan K. L.

2013-01-01

218

Improving thermosyphon solar domestic hot water system model performance. Final report, March 1994--February 1995  

SciTech Connect

Data from an indoor solar simulator experimental performance test is used to develop a systematic calibration procedure for a computer model of a thermosyphoning, solar domestic hot water heating system with a tank-in-tank heat exchanger. Calibration is performed using an indoor test with a simulated solar collector to adjust heat transfer in the heat exchanger and heat transfer between adjacent layers of water in the storage tank. An outdoor test is used to calibrate the calculation of the friction drop in the closed collector loop. Additional indoor data with forced flow in the annulus of the heat exchanger leads to improved heat transfer correlations for the inside and outside regions of the tank-in-tank heat exchanger. The calibrated simulation model is compared to several additional outdoor tests both with and without auxiliary heating. Integrated draw energies are predicted with greater accuracy and draw temperature profiles match experimental results to a better degree. Auxiliary energy input predictions improve significantly. 63 figs., 29 tabs.

Swift, T.N.

1996-09-01

219

Contamination of nonylphenolic compounds in creek water, wastewater treatment plant effluents, and sediments from Lake Shihwa and vicinity, Korea: Comparison with fecal pollution  

USGS Publications Warehouse

Nonylphenolic compounds (NPs), coprostanol (COP), and cholestanol, major contaminants in industrial and domestic wastewaters, were analyzed in creek water, wastewater treatment plant (WWTP) effluent, and sediment samples from artificial Lake Shihwa and its vicinity, one of the most industrialized regions in Korea. We also determined mass discharge of NPs and COP, a fecal sterol, into the lake, to understand the linkage between discharge and sediment contamination. Total NP (the sum of nonylphenol, and nonylphenol mono- and di-ethoxylates) were 0.32–875 ?g L-1 in creeks, 0.61–87.0 ?g L-1 in WWTP effluents, and 29.3–230 ?g g-1 TOC in sediments. Concentrations of COP were 0.09–19.0 ?g L-1 in creeks, 0.11–44.0 ?g L-1 in WWTP effluents, and 2.51–438 ?g g-1 TOC in sediments. The spatial distributions of NPs in creeks and sediments from the inshore region were different from those of COP, suggesting that Lake Shihwa contamination patterns from industrial effluents differ from those from domestic effluents. The mass discharge from the combined outfall of the WWTPs, located in the offshore region, was 2.27 kg d-1 for NPs and 1.00 kg d-1 for COP, accounting for 91% and 95% of the total discharge into Lake Shihwa, respectively. The highest concentrations of NPs and COP in sediments were found in samples at sites near the submarine outfall of the WWTPs, indicating that the submarine outfall is an important point source of wastewater pollution in Lake Shihwa.

Choi, Minkyu; Furlong, Edward T.; Moon, Hyo-Bang; Yu, Jun; Choi, Hee-Gu

2011-01-01

220

Ecological risk assessment of urban creek sediments contaminated by untreated domestic wastewater: potential contribution of antimicrobials and a musk fragrance.  

PubMed

Despite the fact that some hydrophobic pharmaceuticals and personal care products (PPCPs) have been found to accumulate in river sediments, little is known about the contribution of these compounds to the toxicity of the whole sediment. We sampled river sediments from two urban creeks with an unsewered drainage area to investigate the toxicity for a benthic organism, Chironomus yoshimatsui. The concentrations of selected hydrophobic PPCPs, triclosan (TCS), triclocarban (TCC) and galaxolide (HHCB) were analysed using gas chromatographic mass spectroscopy or liquid chromatographic mass spectroscopy and were found to lie within the range 50 to 200 ng g(-1). The toxicity of the three individual contaminants for the chironomid was also determined. The toxicity of TCC was found to be the strongest, with an NOEC value of 2.5 microg g(-1). Combining the toxicity and measured environmental concentration, the ecological risk was assessed and the contribution of these contaminants to the whole sediment toxicity estimated, assuming additivity. The hazard quotient of all three compounds, determined without assessment factor, ranged between 0.01 and 0.1. The combined contribution of the three compounds to total sediment toxicity was as high as 8.2%, but other unknown factors may also make an important contribution. PMID:24191491

Tamura, Ikumi; Kimura, Kumiko; Kameda, Yutaka; Nakada, Norihide; Yamamoto, Hiroshi

2013-01-01

221

Toxicity of phthalates to selected benthic organisms via water and sediment exposures  

SciTech Connect

A three-tiered approach was applied to evaluate the bioavailability and toxicity of a series of phthalic acid esters to selected benthic invertebrates. Tier 1 consisted of 10-day exposures of the test species to the phthalates in water without sediments to determine toxicity. Tier 2 consisted of incorporating the phthalates into natural sediments and evaluating their persistence in phthalate-amended sediments under conditions simulating those of a 10-day toxicity test of contaminated sediments. Tier 3 consisted of performing 10-day exposures of test animals to phthalate-amended sediments. Phthalates were amended to sediments for Tier 3 testing based upon the results of Tier 1 and Tier 2 tests, and an estimation of partitioning between sediment and pore water based upon equilibrium partitioning theory (EPT). Sediments of varying organic carbon content were used to evaluate the bioavailability and toxicity of phthalate-amended sediments. The phthalates included in this study were dimethyl, diethyl, di-n-butyl, butylbenzyl, di-n-hexyl, di-2-ethylhexyl and di-n-decyl phthalate. The sensitivities of the three test species followed the general order in water-only tests: Hyalella azteca > Chironomus tentans > Lumbriculus variegatus. The persistence of selected phthalates from Tier 2 tests, their respective toxicities from Tier 3 tests, and the utility of the EPT approach in assessing phthalate toxicity will be discussed.

Call, D.J.; Markee, T.P.; VandeVenter, F.A.; Cox, D.A.; Geiger, D.L.; Brooke, L.T. [univ. of Wisconsin, Superior, WI (United States). Lake Superior Research Inst.

1995-12-31

222

Polycyclic aromatic hydrocarbons (PAHs) in the water column and sediment core of Deep Bay, South China  

NASA Astrophysics Data System (ADS)

The levels of 15 polycyclic aromatic hydrocarbons (PAHs) were determined in seawater, suspended particulate matter (SPM), surface sediment and core sediment samples of Deep Bay, South China. The average concentrations ? 15PAHs were 69.4 ± 24.7 ng l -1 in seawater, 429.1 ± 231.8 ng g -1 in SPM, and 353.8 ± 128.1 ng g -1 dry weight in surface sediment, respectively. Higher PAH concentrations were observed in SPM than in surface sediment. Temporal trend of PAH concentrations in core sediment generally increased from 1948 to 2004, with higher concentrations in top than in sub-surface, implying a stronger recent input of PAHs owing to the rapid economic development in Shenzhen. Compared with historical data, the PAH levels in surface sediment has increased, and this was further confirmed by the increasing trend of PAHs in the core sediment. Phenanthrene, fluoranthene and pyrene dominated in the PAH composition pattern profiles in the Bay. Compositional pattern analysis suggested that PAHs in the Deep Bay were derived from both pyrogenic and petrogenic sources, and diesel oil leakage, river runoff and air deposition may serve as important pathways for PAHs input to the Bay. Significant positive correlations between partition coefficient in surface sediment to that in water ( KOC) of PAH and their octanol/water partition coefficients ( KOW) were observed, suggesting that KOC of PAHs in sediment/water of Deep Bay may be predicted by the corresponding KOW.

Qiu, Yao-Wen; Zhang, Gan; Liu, Guo-Qing; Guo, Ling-Li; Li, Xiang-Dong; Wai, Onyx

2009-06-01

223

Toxicity tests of effluents with marsh plants in water and sediment  

SciTech Connect

Methods are described for toxicity testing of water and sediment with two varieties of the freshwater marsh plant Echinochloa crusgalli (Linneaus) Palisot de Beauvois (Poaceae), and complex effluents. Two tests are described: a seed germination and early seedling growth test in water, and a survival and seedling growth test in natural and synthetic sediments. Effects of effluents from a sewage treatment plant, tannery, textile mill, pulp and paper mill, coking plant and sewage treatment plant included inhibition of germination, chlorophyll synthesis and growth. The tests with rooted marsh plants were sensitive to pollutants and detected toxicity of a range of pollutants in water and sediment. Synthetic sediments similar to natural sediments allowed toxicity tests to be done under carefully controlled conditions of particle size distribution, organic content, pH, electrode potential (Eh) and cation exchange capacity (CEC).

Walsh, G.E.; Weber, D.E.; Simon, T.L.; Brashers, L.K.

1991-01-01

224

Summary of Suspended-Sediment Concentration Data, San Francisco Bay, California, Water Year 2001  

USGS Publications Warehouse

Suspended-sediment concentration data were collected in San Francisco Bay during water year 2001 (October 1, 2000-September 30, 2001). Optical backscatterance sensors and water samples were used to monitor suspended sediment at two sites in Suisun Bay, three sites in San Pablo Bay, two sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at most sites. Water samples were collected periodically and were analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the electrical output of the optical backscatterance sensors so that a record of suspended-sediment concentrations could be derived. This report presents the data-collection methods used and summarizes the suspended-sediment concentration data collected from October 2000 through September 2001. Calibration curves and plots of edited data for each sensor also are presented.

Buchanan, Paul A.; Ganju, Neil K.

2003-01-01

225

Summary of Suspended-Sediment Concentration Data, San Francisco Bay, California, Water Year 2002  

USGS Publications Warehouse

Suspended-sediment concentration data were collected in San Francisco Bay during water year 2002 (October 1, 2001-September 30, 2002). Optical backscatterance sensors and water samples were used to monitor suspended sediment at two sites in Suisun Bay, three sites in San Pablo Bay, two sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at most sites. Water samples were collected periodically and were analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the electrical output of the optical backscatterance sensors so that a record of suspended-sediment concentrations could be derived. This report presents the data-collection methods used and summarizes the suspended-sediment concentration data collected from October 2001 through September 2002. Calibration curves and plots of edited data for each sensor also are presented.

Buchanan, Paul A.; Ganju, Neil K.

2004-01-01

226

Summary of Suspended-Sediment Concentration Data, San Francisco Bay, California, Water Year 2005  

USGS Publications Warehouse

Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water year 2005 (October 1, 2004-September 30, 2005). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, three sites in San Pablo Bay, two sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at most sites. Water samples were collected periodically and analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the output of the optical sensors so that a record of suspended-sediment concentrations could be derived. This report presents the data-collection methods used and summarizes, in graphs, the suspended-sediment concentration data collected from October 2004 through September 2005. Calibration curves and plots of the processed data for each sensor also are presented.

Buchanan, Paul A.; Lionberger, Megan A.

2007-01-01

227

Bottom Topography, Recent Sedimentation and Water Volume of the Cerro Prieto Dam, NE Mexico  

NASA Astrophysics Data System (ADS)

Cerro Prieto dam, relatively small water reservoir in the NE of Mexico, is characterized by a very high velocity of recent sedimentation, irregular bottom topography and sub-bottom seepage. Very high resolution seismic study using non-linear parametric echo sounder SES-2000 was carried out in this water reservoir, which is one of the main resources of potable water for the Monterrey, the city with a population of about four million inhabitants. A strong difference between water depth and hence the volume capacity calculated by National Commission of Water (Comision Nacional del Agua, CNA), Digital Elevation Model (DEM), and acoustic data was discovered. Very high rate of recent sedimentation due to damming is discussed. SES data interpretation shows that the thickness of recent sediments due to siltation of the reservoir reaches 3.5-4.0 m. Differences between the CNA and SES data indicate storage losses from 8-10 up to 30 million cubic meters due to sedimentation.

Yutsis, V. V.

2012-12-01

228

A multi-level pore-water sampler for permeable sediments  

USGS Publications Warehouse

The construction and operation of a multi-level piezometer (multisampler) designed to collect pore water from permeable sediments up to 230 cm below the sediment-water interface is described. Multisamplers are constructed from 1 1/2 inch schedule 80 PVC pipe. One-quarter-inch flexible PVC tubing leads from eight ports at variable depths to a 1 1/2 inch tee fitting at the top of the PVC pipe. Multisamplers are driven into the sediments using standard fence-post drivers. Water is pumped from the PVC tubing with a peristaltic pump. Field tests in Banana River Lagoon, Florida, demonstrate the utility of multisamplers. These tests include collection of multiple samples from the permeable sediments and reveal mixing between shallow pore water and overlying lagoon water.

Martin, J.B.; Hartl, K.M.; Corbett, D.R.; Swarzenski, P.W.; Cable, J.E.

2003-01-01

229

Assessing the occurrence and distribution of pyrethroids in water and suspended sediments  

USGS Publications Warehouse

The distribution of pyrethroid insecticides in the environment was assessed by separately measuring concentrations in the dissolved and suspended sediment phases of surface water samples. Filtered water was extracted by HLB solid-phase extraction cartridges, while the sediment on the filter was sonicated and cleaned up using carbon and aluminum cartridges. Detection limits for the 13 pyrethroids analyzed by gas chromatography-tandem mass spectrometry were 0.5 to 1 ng L-1 for water and 2 to 6 ng g for the suspended sediments. Seven pyrethroids were detected in six water samples collected from either urban or agricultural creeks, with bifenthrin detected the most frequently and at the highest concentrations. In spiked water samples and field samples, the majority of the pyrethroids were associated with the suspended sediments.

Hladik, M.L.; Kuivila, K.M.

2009-01-01

230

Interparticle collision of natural sediment grains in water  

USGS Publications Warehouse

Elastohydrodynamic theory and measurements of particle impacts on an inclined glass plane in water are used to investigate the mechanics of interparticle collisions in sediment-transporting flows. A collision Stokes number is proposed as a measure of the momentum of an interparticle collision versus the viscous pressure force in the interstitial gap between colliding particles. The viscous pressure force opposes motion of the particles on approach and rebound. A Stokes number of between 39 and 105 is estimated as the critical range below which particle impacts are completely viscously damped and above which impacts are partially elastic. The critical Stokes number is shown to roughly coincide with the Bagnold number transition between macroviscous and grain inertial debris flows and the transition between damped and partially elastic bed load transport saltation impacts. The nonspherical nature of natural particles significantly alters the motion of the center of mass after a partially elastic collision. The normal to the point of contact between the particles does not necessarily go through the center of mass. Thus normal rebound of the center of mass may not occur. A model of particle motion after rebound for particles of arbitrary shape, conserving both linear and angular momentum, is proposed.

Schmeeckle, M.W.; Nelson, J.M.; Pitlick, J.; Bennett, J.P.

2001-01-01

231

A vacuum-operated pore-water extractor for estuarine and freshwater sediments  

USGS Publications Warehouse

A vacuum-operated pore-water extractor for estuarine and freshwater sediments was developed and constructed from a fused-glass air stone attached with aquarium airline tubing to a 30 or 60 cc polypropylene syringe. Pore water is extracted by inserting the air stone into the sediment and creating a vacuum by retracting and bracing the syringe plunger. A hand-operated vacuum pump attached to a filtration flask was also evaluated as an alternative vacuum source. The volume and time to extract pore water varies with the number of devices and the sediment particle size. Extraction time is longer for fine sediments than for sandy sediments. Four liters of sediment generally yield between 500 and 1,500 mL of pore water. The sediment that surrounds and accumulates on the air stone acts as a filter, and, except for the first few milliliters, the collected pore water is clear. Because there is no exposure to air or avenue for escape, volatile compounds andin situ characteristics are retained in the extracted pore water.

Winger, P.V.; Lasier, P.J.

1991-01-01

232

Influence of the water content on X-ray fluorescence core-scanning measurements in soft marine sediments  

Microsoft Academic Search

The X-ray fluorescence (XRF) core scanner provides bulk-sediment chemistry data measured nondestructively at the split core sediment surface. Although this method is widely accepted, there is little known about the effects of physical properties such as density and water content on XRF core scanner data. Comparison of XRF scanner measurements from the sediment surface and dry powder samples of sediment

Rik Tjallingii; Ursula Röhl; Martin Kölling; Torsten Bickert

2007-01-01

233

Towards the development of a combined Norovirus and sediment transport model for coastal waters  

NASA Astrophysics Data System (ADS)

Sewage effluent in coastal waters used for oyster culture poses a risk to human health. The primary pathogen in outbreaks of gastroenteritis following consumption of raw oysters is the Norovirus or "winter vomiting bug". The Norovirus is a highly infectious RNA virus of the Caliciviridae taxonomic family. It has a long survival time in coastal waters (T90 = 30 days in winter). Oysters selectively concentrate Norovirus in their digestive ducts. The virus cannot be removed by conventional depuration. The primary goal of the research is to quantify the risk of Norovirus infection in coastal waters through physically-based high-resolution numerical modelling. Cork Harbour and Clew Bay in Ireland provide case studies for the research. The models simulate a number of complex physical, chemical and biological processes which influence the transport and decay of the virus as well as its bioaccumulation in oyster tissue. The current phase of the research is concerned with the adsorption of the virus to suspended sediment in the water column. Adsorbed viruses may be taken out of the water column when sedimentation occurs and, subsequently, be added to it with resuspension of the bed sediment. Preliminary simulations of the Norovirus-sediment model indicate that suspended sediment can influence the transport of the virus in coastal waters when a high sediment-water partitioning coefficient is used and the model is run under calm environmental conditions. In this instance a certain fraction of the adsorbed viruses are taken out of the water column by sedimentation and end up locked in the bed sediment. Subsequently, under storm conditions, a large number of viruses in the bed are released into the water column by erosion of the bed and a risk of contamination occurs at a time different to when the viruses were initially released into the body of water.

Barry, K.; O'Kane, J. P. J.

2009-04-01

234

Diverted Mississippi River sediment as a potential phosphorus source affecting coastal Louisiana water quality  

Microsoft Academic Search

Mississippi River water and associated sediment are seasonally diverted into Louisiana coastal basins to restore historic hydrologic and salinity regimes and to slow or reverse the widespread wetland loss. More river diversions are planned; however, very little research has been conducted on the potential source of phosphorous (P) of these sediments transported by the Mississippi River into the coastal areas

Wen Zhang; J. R. White; R. D. DeLaune

2012-01-01

235

PRIMARY RESEARCH PAPER Water column oxygen demand and sediment oxygen flux  

E-print Network

creeks Introduction Tidal creeks along the coast of the southeastern United States periodicallyPRIMARY RESEARCH PAPER Water column oxygen demand and sediment oxygen flux: patterns of oxygen metals and sediments are heavily influenced by oxygen consumption or uptake (Medine et al., 1980). Toxic

Mallin, Michael

236

BIOTIC AND ABIOTIC DEGRADATION RATES OF METHYL PARATHION IN FRESHWATER AND ESTUARINE WATER AND SEDIMENT SAMPLES  

EPA Science Inventory

Statistical analysis of degradation rates of methyl parathion samples from two Gulf Coast estuaries over a three-year period indicated that biodegradation occurred in the presence of sediment but was insignificant in water. Sediment rates always showed the same relative five-fold...

237

DEVELOPING MODEL OF BENTHIC-WATER CONTAMINANT TRANSPORT IN BIOTURBATED SEDIMENT  

EPA Science Inventory

Chemicals entering marine waters are incorporated into distinct compartments and these reservoirs are in exchange with one another. he chemo-dynamic storage compartments in marine systems include sediment to the depth of bioturbation (0-50 cm), suspended sediments, dissolved phas...

238

SURVIVAL OF 'DAPHNIA MAGNA' AND 'HYALELLA AZTECA' IN CADMIUM-SPIKED WATER AND SEDIMENT  

EPA Science Inventory

Freshwater sediments and water were spiked with cadmium (Cd) in the laboratory, and toxicity tests were conducted with the cladoceran Daphnia magna and the amphipod Hyalella azteca to determine if Cd in the sediment would cause increased toxicity. The 48-h LC50 values for Daphnia...

239

AUTOMATED LONG-TERM REMOTE MONITORING OF SEDIMENT-WATER INTERFACIAL FLUX  

EPA Science Inventory

Advective flux across the sediment-water interface is temporally and spatially heterogeneous in nature. For contaminated sediment sites, monitoring spatial as well as temporal variation of advective flux is of importance to proper risk management. This project was conducted to ...

240

IMPACT OF STORM-WATER OUTFALLS ON SEDIMENT QUALITY IN CORPUS CHRISTI BAY, TEXAS, USA  

EPA Science Inventory

To determine the quality of sediments and extent of contaminant impacts, a Sediment Quality Triad (SQT) study was conducted at 36 sites in the Corpus Christi Bay, Texas, USA, system. Fifteen of the 36 sites were located near storm-water outfalls, but 13 other sites (i.e., industr...

241

A reservoir operating method for riverine ecosystem protection, reservoir sedimentation control and water supply  

NASA Astrophysics Data System (ADS)

Riverine ecosystem protection requires the maintenance of natural flow and sediment regimes downstream from dams. In reservoir management schedules this requirement should be integrated with sedimentation control and human water supply. However, traditional eco-friendly reservoir operating methods have usually only considered the natural flow regime. This paper seeks to develop a reservoir operating method that accounts for both the natural flow and sediment regimes as well as optimizing the water supply allocations. Herein, reservoir water level (RWL), sediment-occupied ratio of reservoir volume (SOR) and rate of change of SOR (RCSOR) are adopted as three triggers of a drawdown-flushing-based sediment management policy. Two different groups of reservoir operating rule curves (RORCs) are designed for sediment-flushing and non-sediment-flushing years, and the three triggers, RWL, SOR and RCSOR, are used to change the “static” RORCs to “dynamic” ones. The approach is applied to the Wangkuai Reservoir, China to test its effectiveness. This shows that the approach can improve the flexibility of reservoir operators to balance the reservoir management, water supply management and the flow and sediment needs of the downstream riverine ecosystem.

Yin, Xin-An; Yang, Zhi-Feng; Petts, Geoffrey E.; Kondolf, G. Mathias

2014-05-01

242

Physiological Response of Rainbow Trout to Sediment Released during Open-Cut Pipeline Water Crossing Construction  

Microsoft Academic Search

The physiological response of rainbow trout exposed to elevated suspended sediment concentrations downstream of two open-cut pipeline water crossings was investigated. Trout held in cages downstream of construction had increased respiration rates and shorter times till loss of equilibrium during sealed jar bioassays. Differences in blood hematocrit levels between experiments and transects is attributed to sediment concentration and particle size.

SCOTT M. REID; GLENN ISAAC; SERGE METIKOSH; JIM EVANS

2003-01-01

243

Heavy Metals and Arsenic in Sediments, Mussels and Marine Water from Murano (Venice, Italy)  

Microsoft Academic Search

This paper describes a study of the trace element distribution in sediments, marine water and mussel Mytilus galloprovincialis of the Venetian Lagoon around the Island of Murano, an island with a long tradition of glassmaking. Trace elements analysed include Fe, Mn, Zn, Cu, Cr, Pb, Ni, Ag and As. Sediments are contaminated with Zn, Cu, Ag, As and Pb, with

Lorenzino Giusti; Hao Zhang

2002-01-01

244

A probe for sampling interstitial waters of stream sediments and bog soils  

USGS Publications Warehouse

A probe for sampling interstitial waters of stream sediments and bog soils is described. Samples can be obtained within a stratigraphic interval of 2-3 cm, to a depth of 60-80 cm, and with little or no contamination of the samples by sediment or air. ?? 1974.

Nowlan, G.A.; Carollo, C.

1974-01-01

245

[Distribution characteristics of organochlorine pesticides in surface water and sediments from the Mengjin wetland].  

PubMed

The surface water and sediments from the Mengjin wetland were collected. After seperated and concentrated by solid phase extraction and Soxhlet extraction, twenty kinds of organochlorine pesticides (OCPs) in the samples from the Mengjin wetland were analyzed by gas chromatography. In the surface water, 7 kinds of OCPs (incluing alpha-HCH, beta-HCH, gamma-HCH, delta-HCH, 4,4-DDT, heptachor and aldrin) were detected, with the detected ratio of 4.2% -62.5% and the content range of ND-12.21 ng/L. In the sediments, 4,4-DDE and 4,4-DDT were detected, with the detected ratio of 50%-75% and the content range of ND-64.58 ng/g. HCHs and DDTs in the surface water were both lower than the limited value defined by Environmental Quality Standards for Surface Water in China, while the surface sediments in the Mengjin wetland pose a bit high risk comparing with ERL and ERM value of risk evaluation. Distribution characteristics of OCPs components showed that HCHs usually had higher residue levels in surface water, while sediment was the fate of DDTs in the transfer process of materials from water to sediment. OCPs content in the surface water and sediments both decreased in the order of high water period > level water period > low water period. OCPs in the low water seasons were mainly the early residue, but OCPs in the high seasons had some new input in near term in the surface water and sediments. The results suggested that non-point source was one of the important sources of OCPs entering Mengjin wetland. PMID:19662839

Xiao, Chun-Yan; Tai, Chao; Zhao, Tong-Qian; Wu, Li; Zhou, Tian-Jian; Dong, Jing-Jing

2009-06-15

246

Application of multi-objective technique in modeling water and sediment flow in river reaches  

NASA Astrophysics Data System (ADS)

Usually water resources problems consist of multiple objectives that may be conflicting and competing in nature. To evaluate optimal water resources system performances often it is required to obtain a compromise solution satisfying several goals and objectives. For example, in the case of multipurpose reservoir operations, a number of conflicting and competing purposes such as supply of water for conservation uses, downstream flood control, hydropower generation and related environmental objectives are to be optimally satisfied. It may be noted that for deriving maximum benefit from conservation uses reservoir storage should be as high as possible; on the other hand to achieve maximum flood control benefits the storage should be kept as low as possible. Since flood control and conservation objectives are conflicting in nature, higher achievement in flood control objective results in lower attainment of the conservation objectives. In other areas of water resources such as, rainfall runoff modeling, water quality problems, watershed management etc often a number of objectives are required to be satisfied to derive optimal system performances. It is known that one prominent cause of soil erosion and runoff generation from a catchment is related to the effect of rainfall over the catchment and thus water and the sediment discharge at a river station are mainly depended on rainfall and the catchment characteristics. Water and sediment discharge for a river section can be considered as two outputs due to a rainfall input over the catchment. To describe sediment and water flow through river reaches usually separate models are used and the model parameters are estimated using single/multiple optimization routines. Since water and sediment flow are effects with a common cause, a new model can be obtained that can quantify and explain both the effects that is, flow of sediment and water in a river course. In the present study, application of multiple objective optimization technique has described in obtaining parameters of the integrated water-sediment flow model. The integrated model needs to be calibrated using both water and sediment data for a river reach and requires separate objective functions to independently match water and sediment flow variations for a station. The integrated model describing two hydrological variables is highly nonlinear with exponential model form and requires efficient algorithm to identify model parameters. Multiple objectives were framed to calibrate the model using water and sediment data and the model parameters were estimated applying non-dominated sorting genetic algorithm (NSGA-II). The proposed model formulations are demonstrated for simulating suspended sediment load and water discharge in the Mississippi River Basin, USA. Results obtained show that an integrated model having multiple objectives can be developed to describe two hydrological variables with satisfactory performances.

Sil, Briti Sundar; Choudhury, Parthasarathi

2010-10-01

247

Distributions of pesticides and organic contaminants between water and suspended sediment, San Francisco Bay, California  

SciTech Connect

Suspended-sediment and water samples were collected from San Francisco Bay in 1991 during low river discharge and after spring rains. All samples were analyzed for organophosphate, carbamate, and organochlorine pesticides; petroleum hydrocarbons; biomarkers; and polynuclear aromatic hydrocarbons. The objective were to determine the concentrations of these contaminants in water and suspended sediment during two different hydrologic conditions and to determine partition coefficients of the contaminants between water and sediment. Concentrations of hydrophobic contaminants, such as polynuclear aromatic hydrocarbons, varied with location of sample collection, riverine discharge, and tidal cycle. Concentrations of hydrophobic contaminants in suspended sediments were highest during low river discharge but became diluted as agricultural soils entered the bay after spring rains. Polynuclear aromatic hydrocarbons defined as dissolved in the water column were not detected. The concentrations sorbed on suspended sediments were variable and were dependent on sediment transport patterns in the bay. In contrast, the relatively hydrophilic organophosphate pesticides, such as chlorpyrifos and diazinon, had a ore uniform concentration in suspended sediment. These pesticides were detected only after spring rains. Most of the measured diazinon, at least 98% for all samples, was in the dissolved phase. Measured partition coefficients for diazinon generally were uniform, which suggest that suspended-sediment concentrations were close to equilibrium with dissolved concentrations. The concentration of diazinon sorbed to suspended sediments, at any given sampling site, was driven primarily by the more abundant solution concentration. The concentrations of diazinon sorbed to suspended sediments, therefore, were independent of the patterns of sediment movement. 27 refs., 5 figs., 4 tabs.

Domagalski, J.L.; Kuivila, K.M. (Department of the Interior, Sacramento, CA (United States))

1993-12-01

248

Spatial variability of metals in surface water and sediment in the langat river and geochemical factors that influence their water-sediment interactions.  

PubMed

This paper determines the controlling factors that influence the metals' behavior water-sediment interaction facies and distribution of elemental content ((75)As, (111)Cd, (59)Co, (52)Cr, (60)Ni, and (208)Pb) in water and sediment samples in order to assess the metal pollution status in the Langat River. A total of 90 water and sediment samples were collected simultaneously in triplicate at 30 sampling stations. Selected metals were analyzed using ICP-MS, and the metals' concentration varied among stations. Metal concentrations of water ranged between 0.08-24.71 ?g/L for As, <0.01-0.53 ?g/L for Cd, 0.06-6.22 ?g/L for Co, 0.32-4.67 ?g/L for Cr, 0.80-24.72 ?g/L for Ni, and <0.005-6.99 ?g/L for Pb. Meanwhile, for sediment, it ranged between 4.47-30.04 mg/kg for As, 0.02-0.18 mg/kg for Cd, 0.87-4.66 mg/kg for Co, 4.31-29.04 mg/kg for Cr, 2.33-8.25 mg/kg for Ni and 5.57-55.71 mg/kg for Pb. The average concentration of studied metals in the water was lower than the Malaysian National Standard for Drinking Water Quality proposed by the Ministry of Health. The average concentration for As in sediment was exceeding ISQG standards as proposed by the Canadian Sediment Quality Guidelines. Statistical analyses revealed that certain metals (As, Co, Ni, and Pb) were generally influenced by pH and conductivity. These results are important when making crucial decisions in determining potential hazardous levels of these metals toward humans. PMID:22919346

Lim, Wan Ying; Aris, Ahmad Zaharin; Zakaria, Mohamad Pauzi

2012-01-01

249

Remote sensing of suspended sediment water research: principles, methods, and progress  

NASA Astrophysics Data System (ADS)

In this paper, we reviewed the principle, data, methods and steps in suspended sediment research by using remote sensing, summed up some representative models and methods, and analyzes the deficiencies of existing methods. Combined with the recent progress of remote sensing theory and application in water suspended sediment research, we introduced in some data processing methods such as atmospheric correction method, adjacent effect correction, and some intelligence algorithms such as neural networks, genetic algorithms, support vector machines into the suspended sediment inversion research, combined with other geographic information, based on Bayesian theory, we improved the suspended sediment inversion precision, and aim to give references to the related researchers.

Shen, Ping; Zhang, Jing

2011-12-01

250

The mechanisms of contaminants release due to incipient motion at sediment-water interface  

NASA Astrophysics Data System (ADS)

Sediments in many rivers and lakes are subjected to resuspension due to a combination of hydrodynamics. However, the roles of contaminant-contained dissolved and particulate sediments during the resuspension release are rarely studied. This study focuses on the release quantity of contaminants in both water phase and solid phase. Conservative tracer (NaCl) and reactive tracer (Phosphorus) were respectively added to cohesive fine-grained sediments and non-cohesive coarse-grained sediments. A range of typical shear stress was conducted to characterize the time-depended release of contaminants in a laboratory flume. When the sediment started to move, the concentration of contaminant in the overlying water increased with the bed shear stress, but the dissolved contaminants responded faster than the particulate ones. The observed contaminant release process can be divided into three main stages: the initial two hours fast mixing: the release contribution of pore water could reach up to 75%; the middle 4-6 h adsorption: the partitioning coefficient of contaminant between water phase and solid phase decreased over the time, and the adsorption of contaminates from resuspended sediment dominated the negative release; the last equilibrium stage: the desorption and adsorption reached equilibrium, and the reactive contaminant made an impact on the water quality in the solid phase. The existing formulas to evaluate the release flux are far from practice meaning as the sediment contaminants undergo a very complex release process.

Zhu, HongWei; Cheng, PengDa; Zhong, BaoChang; Wang, DaoZeng

2014-08-01

251

Influence of water quality parameters on occurrence of polybrominated diphenyl ether in sediment and sediment to biota accumulation.  

PubMed

Polybrominated diphenyl ether (PBDE) concentrations in sediment and fish from 12 principal rivers in Taiwan were investigated to determine their association with water quality parameters as well as the biota-sediment accumulation factor (BSAF) in fish with different living patterns. The highest PBDE concentration in sediment was found in the Bajhang River (261 ng g(-1) dryweight (d.w.)) and the lowest in the Beinan River and the Da-an River (0.17 ng g(-1) d.w.). The PBDE concentrations in fish samples ranged from 1.28 ng g(-1) d.w. (Oreochromis niloticus niloticus) in the Yanshuei River to 33.7 ng g(-1) d.w. (Varico rhinos barbatulus) in the Da-an River. We conclude that PBDEs contamination in sediment was significantly affected by NH(3)-N, pH, and DO. The BSAF results showed a parabolic trend from low- to high-brominated BDEs. Fish easily accumulated the congeners BDE-47, -100, -119, -126, and -154 from sediment. The BSAF decreased in the following order: PeBDE>HxBDE>TeBDE>other BDEs. Principle component analysis showed that demersal fish have different PBDE sources than do pelagic fish. We conclude that living and feeding habits are critical factors affecting PBDE accumulation in fish. PMID:23218414

Chen, Chung-Yu; Tien, Chien-Jung; Sun, Yih-Min; Hsieh, Chia-Yi; Lee, Ching-Chang

2013-03-01

252

Characterization of bottom-sediment, water, and elutriate chemistry at selected stations at Reelfoot Lake, Tennessee  

USGS Publications Warehouse

To better-understand and predict the potential effect of dredging on water quality at Reelfoot Lake, chemical analyses were conducted on samples of lake water, bottom sediment, and elutriate water. Chemical analyses were conducted on samples of lake water, bottom sediment, and elutriate water collected at five stations in the lake during November 1988. Lake water was of the calcium magnesium bicarbonate type with an average dissolved-solids concentration of 120 milligrams per liter. Trace constituents were present in bottom sediments at concentrations representative of their average relative abundance in the earth?s crust. Elutriate waters prepared by mixing bottom sediment and lake water had suspended-solids concentrations as high as 2,000 milligrams per liter which exerted significant oxygen demand Trace constituents in the unfiltered elutriate waters were elevated with respect to lake water; elevated concentrations were attributable to the increased suspended-solids concentrations. Concentrations of total-recoverable copper, lead., and zinc in many elutriate waters exceeded U.S. Environmental Protection Agency?s water-quality criteria for the protection of freshwater aquatic life. The toxicity of elutriate waters, as measured by a 48-hour bioassay with Ceriodaphnia dubia, was low.

Broshears, R.E.

1991-01-01

253

METAL SPECIATION IN SOIL, SEDIMENT, AND WATER SYSTEMS VIA SYNCHROTRON RADIATION RESEARCH  

EPA Science Inventory

Metal contaminated environmental systems (soils, sediments, and water) have challenged researchers for many years. Traditional methods of analysis have employed extraction methods to determine total metal content and define risk based on the premise that as metal concentration in...

254

Three-dimensional acoustic propagation through shallow water internal, surface gravity and bottom sediment waves  

E-print Network

This thesis describes the physics of fully three-dimensional low frequency acoustic interaction with internal waves, bottom sediment waves and surface swell waves that are often observed in shallow waters and on continental ...

Shmelev, Alexey Alexandrovich

2011-01-01

255

Development of a standard operating procedure for the collection of pyrethroids in water and sediment matrices  

EPA Science Inventory

Through a Regional Applied Research Effort grant to the United States Geological Survey, Region 9 collaborated with ORD on this project to develop a standard operating procedure for collection of water and sediment samples for pyrethroid analysis. ...

256

PRECISION OF DIALYSIS (PEEPER) SAMPLING OF CADMIUM IN MARINE SEDIMENT INTERSTITIAL WATER  

EPA Science Inventory

Isolating and analyzing interstitial water (IW) during sediment toxicity tests enables researchers to relate concentrations of contaminants to responses of organisms, particularly when IW is a primary route of exposure to bioavailable contaminants by benthic dwelling organisms. W...

257

MONITORING OXIDATION-REDUCTION PROCESSES IN GROUND WATERS, SEDIMENTS, AND SOILS  

EPA Science Inventory

The overall goal of this project is to develop recommendations and technical guidelines for evaluating redox processes in contaminated ground water, sediment, and soil systems. One specific goal is to evaluate existing methodologies for determining Dissolved Oxygen (DO) concentra...

258

TOXICITY TESTS OF EFFLUENTS WITH MARSH PLANTS IN WATER AND SEDIMENT  

EPA Science Inventory

Methods are described for toxicity testing of water and sediment with the rooted marsh plants, Echinochloa crusgalli var. crusgalli and var. zelavensis (freshwater) and Spartina alterniflora (estuarine). ive industrial effluents, a sewage treatment plant effluent and a herbicide ...

259

HEXACHLOROBENZENE UPTAKE BY FATHEAD MINNOWS AND MACRO INVERTEBRATES IN RECIRCULATING SEDIMENT/WATER SYSTEMS  

EPA Science Inventory

Fathead minnow (Pimephales promelas), the worm, Lumbriculus variegatus, and the amphipods Hyalella azteca and Gammarus lacustris were exposed to hexachlorobenzene (HCB) in water with and without a bed of HCB-spiked sediment. ater HCB concentrations were maintained by recirculatio...

260

30 CFR 77.216-5 - Water, sediment or slurry impoundments and impounding structures; abandonment.  

Code of Federal Regulations, 2010 CFR

...slurry impoundments and impounding structures; abandonment. 77.216-5 Section 77.216-5 Mineral...slurry impoundments and impounding structures; abandonment. (a) Prior to abandonment of any water, sediment, or slurry...

2010-07-01

261

30 CFR 77.216-5 - Water, sediment or slurry impoundments and impounding structures; abandonment.  

Code of Federal Regulations, 2012 CFR

This plan shall provide for major slope stability, include a schedule for the plan's implementation and, except as provided in paragraph (b) of this section, contain provisions to preclude the probability of future impoundment of water, sediment, or...

2012-07-01

262

30 CFR 77.216-5 - Water, sediment or slurry impoundments and impounding structures; abandonment.  

Code of Federal Regulations, 2013 CFR

This plan shall provide for major slope stability, include a schedule for the plan's implementation and, except as provided in paragraph (b) of this section, contain provisions to preclude the probability of future impoundment of water, sediment, or...

2013-07-01

263

Sediment load from major rivers into Puget Sound and its adjacent waters  

USGS Publications Warehouse

Each year, an estimated load of 6.5 million tons of sediment is transported by rivers to Puget Sound and its adjacent waters—enough to cover a football field to the height of six Space Needles. This estimated load is highly uncertain because sediment studies and available sediment-load data are sparse and historically limited to specific rivers, short time frames, and a narrow range of hydrologic conditions. The largest sediment loads are carried by rivers with glaciated volcanoes in their headwaters. Research suggests 70 percent of the sediment load delivered to Puget Sound is from rivers and 30 percent is from shoreline erosion, but the magnitude of specific contributions is highly uncertain. Most of a river's sediment load occurs during floods.

Czuba, Jonathan A.; Magirl, Christopher S.; Czuba, Christiana R.; Grossman, Eric E.; Curran, Christopher A.; Gendaszek, Andrew S.; Dinicola, Richard S.

2011-01-01

264

Fremont Lake, Wyoming--some aspects of the inflow of water and sediment  

USGS Publications Warehouse

Fremont Lake is a large (20.6 sq km), deep lake (185 m) in western Wyoming. Average annual inflow of water is about 5.1 cu meters/sec, and this discharge is equaled or exceeded about 23% of the time. Annual instantaneous peak flows of Pine Creek usually exceed 30 cu m/sec and the 100-year flood is about 80 cu m/sec. About 800 tons of sediment are delivered to the lake annually; annual deposition of sediment in the northern lake area throughout the last 10,000 years about equals contemporary values of sediment inflow. Only small quantities of fine-gradient sediment are transported beyond the delta at the northern end of the lake. Current rates of deposition in the delta are about 1 to 3 mm/yr. Sediment in the delta generally is sand size; elsewhere in the lake, sediment generally is clay and silt size. (USGS)

Emmett, W.W.; Averett, R.C.

1989-01-01

265

Large-eddy simulations of particle sedimentation in a longitudinal sedimentation basin of a water treatment plant. Part 2: The effects of baffles  

Microsoft Academic Search

The process of particle sedimentation in a three-dimensional longitudinal basin with vertical baffles in a water treatment plant is studied using large-eddy simulations (LES). The objective of this study is to investigate the effect of the baffle installations on the particle settling performance of the sedimentation basin. The fluid mixture simulates typical contaminated water in which the contaminants are represented

M. Al-Sammarraee; A. Chan

2009-01-01

266

Hydrothermal sediments are a source of water column Fe and Mn in the Bransfield Strait, Antarctica  

NASA Astrophysics Data System (ADS)

Short sediment cores were collected from ?1100 m water depth at the top of Hook Ridge, a submarine volcanic edifice in the Central Basin of the Bransfield Strait, Antarctica, to assess Fe and Mn supply to the water column. Low-temperature hydrothermal fluids advect through these sediments and, in places, subsurface H2S is present at high enough concentrations to support abundant Sclerolinum sp., an infaunal tubeworm that hosts symbiotic thiotrophic bacteria. The water column is fully oxic, and oxygen penetration depths at all sites are 2-5 cmbsf. Pore water Fe and Mn content is high within the subsurface ferruginous zone (max. 565 ?mol Fe L-1, >3-7 cmbsf)-14-18 times higher than values measured at a nearby, background site of equivalent water depth. Diffusion and advection of pore waters supply significant Fe and Mn to the surface sediment. Sequential extraction of the sediment demonstrates that there is a significant enrichment in a suite of reactive, authigenic Fe minerals in the upper 0-5 cm of sediment at one site characterised by weathered crusts at the seafloor. At a site with only minor authigenic mineral surface enrichment we infer that leakage of pore water Fe and Mn from the sediment leads to enriched total dissolvable Fe and Mn in bottom waters. An Eh sensor mounted on a towed package mapped a distinct Eh signature above this coring site which is dispersed over several km at the depth of Hook Ridge. We hypothesise that the main mechanism for Fe and Mn efflux from the sediment is breach of the surface oxic layer by the abundant Sclerolinum sp., along with episodic enhancements by physical mixing and resuspension of sediment in this dynamic volcanic environment. We propose that Hook Ridge sediments are an important source of Fe and Mn to the deep waters of the Central Basin in the Bransfield Strait, where concentrations are sustained by the benthic flux, and Fe is stabilised in the water column as either colloidal phases or ligand-bound dissolved species. Entrainment of this water mass into the Drake Passage and thereby the Antarctic Circumpolar Current could provide a significant metal source to this HNLC region of the Southern Ocean if mixing and upwelling occurs before removal of this metal pool to underlying sediments. Sediment-covered volcanic ridges are common within rifted margins and may play a previously overlooked role in the global Fe cycle.

Aquilina, Alfred; Homoky, William B.; Hawkes, Jeffrey A.; Lyons, Timothy W.; Mills, Rachel A.

2014-07-01

267

Dissolved sulfide distributions in the water column and sediment pore waters of the Santa Barbara Basin  

USGS Publications Warehouse

Dissolved sulfide concentrations in the water column and in sediment pore waters were measured by square-wave voltammetry (nanomolar detection limit) during three cruises to the Santa Barbara Basin in February 1995, November-December 1995, and April 1997. In the water column, sulfide concentrations measured outside the basin averaged 3 ?? 1 nM (n = 28) in the 0 to 600 m depth range. Inside the basin, dissolved sulfides increased to reach values of up to 15 nM at depths >400 m. A suite of box cores and multicores collected at four sites along the northeastern flank of the basin showed considerable range in surficial (400 ??M at 10 cm. Decreases in water-column nitrate below the sill depth indicate nitrate consumption (-55 to -137 ??mole m-2 h-1) similar to nearby Santa Monica Basin. Peaks in pore-water iron concentrations were generally observed between 2 and 5 cm depth with shallowest peaks at the 590 m site. These observations, including observations of the benthic microfauna, suggest that the extent to which the sulfide flux, sustained by elevated pore-water concentrations, reaches the water column may be modulated by the abundance of sulfide-oxidizing bacteria in addition to iron redox and precipitation reactions.

Kuwabara, J.S.; VanGeen, A.; McCorkle, D.C.; Bernhard, J.M.

1999-01-01

268

Heavy metal profile of water, sediment and freshwater cat fish, Chrysichthys nigrodigitatus (Siluriformes: Bagridae), of Cross River, Nigeria.  

PubMed

Cross River serves as a major source of drinking water, transportation, agricultural activities and fishing in Cross River State, Nigeria. Since there is no formal control of effluents discharged into the river, it is important to monitor the levels of metals contaminants in it, thus assessing its suitability for domestic and agricultural use. In order to determine this, three sampling stations designated as Ikom (Station I), Obubra Ogada (Station II) and Calabar (Station III) were randomly selected to study. For this, ten samples of the freshwater Silver Catfish (Chryshchythys nigrogitatus) (29.4-39.5cm SL, 310-510g), sediment and water were collected from each sampling Station from June 2009-June 2010. The heavy metals profiles ofZn, Cu, Fe, Co, Pb, Cd and Cr, in water, sediments and fish muscle were analyzed by atomic absorption spectrophotometry (AAS). In fish, the heavy metals concentration was found to be Cu>Fe>Zn>Cu>Pb>Cd>Co; the highest mean concentration of Copper (0.297 +/- 0.022 microg/g), Cadmium (0.011 +/- 0.007 microg/g), Iron (0.371 +/- 0.489 microg/g), Lead (0.008 +/- 0.008 microg/g), were determined for the fish. In water, the order was found to be Fe>Pb>Zn>Cu>Cr>Cd>Co; the highest mean concentration of Iron (0.009 +/- 0.00) microg/g), Copper (0.015 +/- 0.01 microg/g), Lead (0.0002 +/- 0.00 microg/g) Cadmium (0.0006 +/- 0.001 microg/g), Zinc (0.0036 +/- 0.003 microg/g), were observed in the surface water, respectively. The highest mean concentration of Copper (0.037 +/- 0.03 microg/g), Iron (0.053 +/- 0.04 microg/g), Lead (0.0002 +/- 0.00 microg/g), Cobalt (0.0002 +/- 0.00 microg/g), Cadmium (0.0006 +/- 0.001 microg/g) and Zinc (.009 +/- 0.0015 microg/g) was observed in the bottom water. In sediments, the concentration order found was Zn>Fe>Cu>Pb>Co>Cd; the highest mean concentration of 0.057 +/- 0.04 microg/g, 0.043 +/- 0.03 microg/g, 0.0006 +/- 0.00 microg/g, 0.0002 +/- 0.00 microg/g, 0.0009 +/- 0.00 microg/g, 0.099 +/- 0.00404 microg/g in Iron, Copper, Lead, Cobalt, Cadmium and Zinc were observed in the sediment, respectively; Chromium was not detected in the sediment for the whole sampling area. Most of the heavy metals were below the maximum allowable levels set by the WHO, FEPA and USEPA, except Zinc which mean concentration of 0.099 +/- 0.00404 microg/g was above the recommended limit of 0.0766 microg/g of USEPA in the sediment at Ikom. This implies that the waste assimilation capacity of the river is high, a phenomenon that could be ascribed to dilution, sedimentation and continuous water exchange. This is an indication that an urban and industrial waste discharged into the Cross River has a significant effect on the ecological balance of the river. Thus fish species from the Cross River harvested are safe for human consumption. PMID:23025098

Ayotunde, Ezekiel Olatunji; Offem, Benedict Obeten; Ada, Fidelis Bekeh

2012-09-01

269

The effects of water flow and sedimentation on interactions between massive Porites and algal turf  

NASA Astrophysics Data System (ADS)

Interactions between scleractinian corals and benthic algae can be an important process structuring reef communities, yet interaction dynamics are not fixed and may be influenced by abiotic factors such as sedimentation, a process often underlying reef degradation. However, rates of sedimentation and the effects of trapped sediments may be influenced by water flow. The first goal of this study was to quantify gradients in sedimentation and flow along fringing and back reefs of the north shore of Moorea, French Polynesia, and determine whether such gradients correlate with changes in the frequency and outcomes of massive Porites-algal turf interactions. On the back reef, the frequency of Porites-algal turf interactions and the competitive success of algal turfs increased significantly with decreasing flow. Sedimentation, however, was not a significant driver of the observed patterns. Along fringing reefs, in the absence of a flow gradient, it was the gradient in sedimentation that best explained spatial variation in Porites-algal turf interaction frequencies and the competitive success of algal turfs. The second goal was to quantify the separate and combined effects of flow and sedimentation on Porites-algal turf interactions in a laboratory setting. The combined effects of low flow and sedimentation significantly increased the area of Porites tissue damaged when in contact with algal turf, while high flow attenuated the negative effects of sedimentation. Together, these results implicate flow and sedimentation as important drivers of biological interactions between massive Porites and algal turf.

Gowan, Jennifer C.; Tootell, Jesse S.; Carpenter, Robert C.

2014-09-01

270

Transport of Cryptosporidium parvum in Surface Waters: Interplay of Hydrodynamic Processes, Sediments, and Biofilms  

NASA Astrophysics Data System (ADS)

Understanding the movement of pathogens in the environment is necessary to ensure the safety and protection of municipal water supply systems. Cryptosporidium parvum is a human pathogen of particular concern as it is common in surface waters of the United States, it can survive for long periods of time in the environment, and it is difficult to disinfect in water treatment plants. The transport of oocysts through watersheds can be mediated by interactions with the stream channel and suspended particles in the water column. For example, the association of C. parvum oocysts with suspended particles can alter the effective physical properties of the oocysts and increase their settling velocity. The hydrodynamic coupling of the overlying water with the pore water of the sediment bed can carry oocysts from the surface water into the sediment bed. Surface-attached communities of microorganisms, called biofilms, are ubiquitous in surface water systems and can capture C. parvum oocysts. Laboratory experiments were conducted at multiple scales (flowcell, batch, and flume) to determine the association of oocysts with sediments and biofilm communities and to assess the impact of this association on C. parvum transport. The effects of flow conditions, water chemistry, sediment composition, biofilm composition, and biofilm structure on these associations were all evaluated. The experimental results demonstrate that oocyst-sediment-biofilm interactions have significant implications for the propagation of C. parvum oocysts through watersheds and should generally be considered when predicting the fate of pathogens in the environment.

Searcy, K. E.; Packman, A. I.; Atwill, E. R.; Harter, T.

2005-05-01

271

Determination of pentachlorophenol in water and aquifer sediments by high-performance liquid chromatography  

USGS Publications Warehouse

Methods for the determination of pentachlorophenol (PCP) in water and aquifer sediments are presented. Reverse-phase high-performance liquid chromotography employing ion suppression and gradient elution is used. PCP can be determined directly in water at a lower limit of detection Of 0.2 micrograms per liter. For extracts of sediment, PCP can be determined to a lower limit of 1.0 micrograms per kilogram.

Goerlitz, D.F.

1981-01-01

272

Organochlorine Pesticides in Water, Sediment, Crops, and Human Fluids in a Farming Community in Ghana  

Microsoft Academic Search

A total of 208 samples of water, sediment, tomato crops, blood, and mothers' breast milk were collected from the environs\\u000a of Akumadan, a prominent vegetable-farming community in Ghana. The samples were analyzed for organochlorine (OC) pesticide\\u000a residues. Lindane and endosulfan were found in water and sediment, while other OC pesticide residues, such as hexachlorobenzene\\u000a (HCB), p,p?-DDE, and heptachlor epoxide, were

W. J. Ntow

2001-01-01

273

Universal scaling of dissolved oxygen distribution at the sediment-water interface: A power law  

Microsoft Academic Search

Dissolved oxygen (DO) distribution at the sediment-water interface of a flow over a smooth bed is investigated for Reynolds numbers .360 and ,4,090. These conditions are commonly encountered in streams, wetlands, and lakes. A power-law scaling of DO distribution is derived and compared with experimental data. The scaling analysis is based on DO flux at the sediment-water interface in a

Miki Hondzo; Tom Feyaerts; Richard Donovan; Ben L. O'Connor

2005-01-01

274

Contribution of ammonia, metals, and nonpolar organic compounds to the toxicity of sediment interstitial water from an Illinois River tributary  

Microsoft Academic Search

Toxicity of Illinois River bulk sediment, sediment interstitial (pore) water and elutriates to the oligochaete Lumbriculus variegatus, fathead minnow (Pimephales promelas) and the amphipod Hyalella azteca was compared to determine the most representative aqueous fraction for toxicity identification evaluation (TIE) studies. Toxicity of pore water corresponded better than elutriates to bulk sediment toxicity. Subsequent TIE procedures conducted with the cladoceran

Mary K. Schubauer-Berigan; Gerald T. Ankley

1991-01-01

275

The influence of geology and land use on arsenic in stream sediments and ground waters in New England, USA  

E-print Network

The influence of geology and land use on arsenic in stream sediments and ground waters in New that used arsenical pesticides on crops. Stream sediments, which integrate both natural and anthropogenic July 2006 Abstract Population statistics for As concentrations in rocks, sediments and ground water

276

Occurrence of perfluorinated compounds in the aquatic environment as found in science park effluent, river water, rainwater, sediments, and biotissues.  

PubMed

The current article maps perfluoroalkyl acids (PFAAs) contamination in the largest Science Park of Taiwan. The occurrence of ten target PFAAs in the effluent of an industrial wastewater treatment plant (IWWTP), its receiving rivers, rainwater, sediment, and the muscles and livers of fish was investigated. All target PFAAs were found in effluent of IWWTP, in which perfluorooctane sulfonate (PFOS) (6,930 ng/L), perfluorohexyl sulfonate (PFHxS) (2,662 ng/L) and perfluorooctanoic acid (PFOA) (3,298 ng/L) were the major constituents. Concentrations of PFBS and PFOS in the IWWTP downstream areas have exceeded safe concentration levels of avian and aquatic life, indicating a potential risk to wildlife in those areas. In sediment samples, predominant contaminants were PFOS (1.5-78 ng/g), PFOA (0.5-5.6 ng/g), and perfluorododecanoic acid (PFDoA) (nd-5.4 ng/g). In biological tissue samples, concentrations as high as 28,933 ng/g of PFOS were detected in tilapia and catfish liver samples. A positive correlation for log (C sediment/C water) and log (C tissue/C water) was found. The concentration and proportion (percentage of all PFAAs) of PFOS found in biotissue samples from the Keya River (which receives industrial wastewater) were found to be much greater (200 times) than those of samples from the Keelung River (which receives mainly domestic wastewater). These findings suggest that the receiving aquatic environments and, in turn, the human food chain can be significantly influenced by industrial discharges. PMID:24464397

Lin, Angela Yu-Chen; Panchangam, Sri Chandana; Tsai, Yu-Ting; Yu, Tsung-Hsien

2014-05-01

277

A comparison of the accumulation of phenanthrene by marine amphipods in water versus sediment  

SciTech Connect

The objective of this research is to compare the accumulation of the polycyclic aromatic hydrocarbon phenanthrene by marine amphipods from sediment and interstitial water versus from a water only exposure system. The equilibrium partitioning theory assumes that the exposure and response of benthic invertebrates are the same when exposed to the same contaminant concentration in water and interstitial water. In this series of experiments, three infaunal marine amphipod species; Eohaustorius estuarius (non tube-forming, burrowing amphipod), Leptocheirus plumulosus (burrow-building amphipod) and Grandidierella japonica (tube-building amphipod), were exposed to {sup 14}C-phenanthrene under three experimental conditions: (1) sediment spiked at a concentration resulting in an interstitial water concentration of 2.5 {micro}g/l phenanthrene; (2) sediment spiked at a concentration resulting in interstitial water concentration of 2.5 {micro}g/l and the overlying water spiked at 2.5 {micro}g/l phenanthrene; (3) a water only exposure with the water at a concentration of 2.5 {micro}g/l phenanthrene, The exposures were conducted in a static renewal system with the overlying and exposure water being replaced every 8 hours. The bioaccumulation of phenanthrene was followed over 72 hours. In all three species of amphipods, the accumulation of phenanthrene was significantly greater in the water only exposure than in the two sediment exposures. At 72 hours, the amphipod body burdens of phenanthrene in the water only exposures were, depending on the species, 7 to 24 times that of the sediment only exposures. The results suggest that water only exposures may overestimate sediment or interstitial exposure to phenanthrene and other nonionic, lipophilic compounds.

Fusi, T.; Weber, L.J. [Oregon State Univ., Newport, OR (United States). Hatfield Marine Science Center

1995-12-31

278

LIQUID AND GAS CHROMATOGRAPHIC ANALYSIS OF DIETHYL PHTHALATE IN WATER AND SEDIMENT  

EPA Science Inventory

Diethyl phthalate was determined in water and sediment by high performance liquid chromatography (HPLC) and in water by gas-liquid chromatography with electron capture detection (GLC-ECD). Water samples were extracted with hexane, using a high-speed homogenizer-ultrasonic apparat...

279

Analysis of national water-pollution-control policies. 2. Agricultural sediment control  

Microsoft Academic Search

A national water network model is used to analyze the likely effects of agricultural sediment-control policies on the quality of the nation's waters. This analysis is believed superior to previous assessments based mainly on erosion estimates without accounting for the characteristics of the receiving water or the contribution of pollutants from nonagricultural activities. Specifically, while the earlier assessments concluded that

Leonard P. Gianessi; Henry M. Peskin

1981-01-01

280

Analysis of national water pollution control policies: 2. Agricultural sediment control  

Microsoft Academic Search

Application of a national water network model permits an analysis of the likely affects of agricultural sediment control policies on the quality of the nation's waters. This analysis is believed superior to previous assessments based mainly on erosion estimates without accounting for the characteristics of the receiving water or the contribution of pollutants from nonagricultural activities. Specifically, while the earlier

Leonard P. Gianessi; Henry M. Peskin

1981-01-01

281

CHANGES IN TRACE METAL CONCENTRATIONS IN DETROIT RIVER WATER AND SEDIMENT SINCE THE 1980S  

EPA Science Inventory

Water samples werre collected from the Trenton Channel of the Detroit River between March 1995 and June 1996. Both unfiltered and filtered samples were collected. Sediments were collected by MDEQ between 1993 and 1996. Water results were compared to those for water samples collec...

282

Heavy metals in water, sediment and tissues of Leuciscus cephalus from a stream in southwestern Turkey  

Microsoft Academic Search

Concentrations of heavy metals (Cd, Cr, Cu, Pb and Zn) were measured in water, bottom sediment and tissues (muscle and gills) of Leuciscus cephalus from the Dipsiz stream in the Yatagan basin (southwestern Turkey), the site of a thermal power plant. Results for levels in water were compared with national and international water quality guidelines, as well as literature values

Ahmet Demirak; Fevzi Yilmaz; A. Levent Tuna; Nedim Ozdemir

2006-01-01

283

Effects of sediment transport and seepage direction on hydraulic properties at the sediment-water interface of hyporheic settings  

NASA Astrophysics Data System (ADS)

SummaryRelations between seepage flux and hydraulic properties are difficult to quantify in fluvial settings because of the difficulty in measuring these variables in situ. Tests conducted in a 1.5-m diameter by 1.5-m tall sediment-filled tank indicate that hydraulic gradient increased and hydraulic conductivity ( K) decreased following the onset of downward seepage but both parameters were little changed following the onset of upward seepage. Reductions in K during downward seepage were more pronounced when surface-water current was sufficient to mobilize sediment on the bed. Averaged ratios of K determined during upward seepage to K determined during downward seepage ( K up/K down) through a sand-and-gravel bed increased from 1.4 to 1.7 with increasing surface-water velocity, and decreased to slightly greater than 1 when the sediment bed became fully mobile. K up/K down for tests conducted with a silt veneer on the bed surface was greater than 2 for all but the fastest surface-water velocities. Substantial reductions in K also were associated with a silt floc that formed on the bed surface during and following test runs. Although the silt floc was typically less than 0.5 mm in thickness, most of the hydraulic gradient was distributed across this thin layer. K of the thin silt floc was reduced by two to three orders of magnitude relative to the underlying sediment. Directional bias in K and relation between K and surface-water velocity require the presence or absence of a layer of lower- K sediment at or near the bed surface, without which no reduction in K and corresponding increase in hydraulic gradient can occur at the bed surface. The lack of prior observation of the consistent bias in K associated with seepage direction is somewhat surprising given the numerous studies where K has been measured in fluvial settings, but may be explained by the small value of the bias relative to the typical uncertainty associated with field determinations of K. If shown to exist in field settings, this bias and its relation to fluvial processes will be relevant to many studies conducted in hyporheic settings that require determination of fluxes across the sediment-water interface.

Rosenberry, Donald O.; Pitlick, John

2009-07-01

284

Effects of sediment transport and seepage direction on hydraulic properties at the sediment-water interface of hyporheic settings  

USGS Publications Warehouse

Relations between seepage flux and hydraulic properties are difficult to quantify in fluvial settings because of the difficulty in measuring these variables in situ. Tests conducted in a 1.5-m diameter by 1.5-m tall sediment-filled tank indicate that hydraulic gradient increased and hydraulic conductivity (K) decreased following the onset of downward seepage but both parameters were little changed following the onset of upward seepage. Reductions in K during downward seepage were more pronounced when surface-water current was sufficient to mobilize sediment on the bed. Averaged ratios of K determined during upward seepage to K determined during downward seepage (Kup/Kdown) through a sand-and-gravel bed increased from 1.4 to 1.7 with increasing surface-water velocity, and decreased to slightly greater than 1 when the sediment bed became fully mobile. Kup/Kdown for tests conducted with a silt veneer on the bed surface was greater than 2 for all but the fastest surface-water velocities. Substantial reductions in K also were associated with a silt floc that formed on the bed surface during and following test runs. Although the silt floc was typically less than 0.5 mm in thickness, most of the hydraulic gradient was distributed across this thin layer. K of the thin silt floc was reduced by two to three orders of magnitude relative to the underlying sediment. Directional bias in K and relation between K and surface-water velocity require the presence or absence of a layer of lower-K sediment at or near the bed surface, without which no reduction in K and corresponding increase in hydraulic gradient can occur at the bed surface. The lack of prior observation of the consistent bias in K associated with seepage direction is somewhat surprising given the numerous studies where K has been measured in fluvial settings, but may be explained by the small value of the bias relative to the typical uncertainty associated with field determinations of K. If shown to exist in field settings, this bias and its relation to fluvial processes will be relevant to many studies conducted in hyporheic settings that require determination of fluxes across the sediment-water interface.

Rosenberry, D.O.; Pitlick, J.

2009-01-01

285

ENTRAINMENT OF SEDIMENTS AND DREDGED MATERIALS IN SHALLOW LAKE WATERS  

EPA Science Inventory

Results of recent laboratory experiments concerned with the ntrainment and deposition of sediment is in lakes are reported. rom these experiments and other recent work, quantitative descriptions and parameterizations of entrainment and deposition processes are made. n the interpr...

286

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

PubMed

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. PMID:25602339

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

287

Effect of sediment settling on controlling golden mussel invasion in water transfer project  

NASA Astrophysics Data System (ADS)

Inter-basin water transfer projects have been widely used to solve uneven distribution of water resources and water shortage in China. Along with the transferring of water resources, golden mussel (Limnoperna fortunei), the filter-collector macro-invertebrate species originating from southern China has also been inadvertently transferred to new aquatic environment, resulting in quick and uncontrolled spread of the species. The golden mussels are invasive by nature and endowed with a strong byssus for attaching onto their habitat, allowing them to easily invade natural and artificial aquatic systems, which was resulted in high-density golden mussel attachment that causes serious bio-fouling. Invasion and bio-fouling by golden mussels in water transfer systems has drawn attention widely because it has resulted in high resistance to water flow, corrosion of pipe walls and even clogging of tunnels, as well as causing water pollution and ecological imbalance in the regions that receive water infested with golden mussels. Field investigation was conducted along the East River, which is the main drinking water resource for Cantong province and Hongkong, China, to study the natural habitats of golden mussels. Surveys of water transfer tunnels which carry water from the East River to several big cities in Cantong province were done to study golden mussel invasion and attachment in tunnels. It is found that in the natural habitat, golden mussels mainly attach to bedrock and bank stones and solid surfaces facing upstream, while no golden mussels are attached on the surfaces facing downstream and suffering sediment deposition. In the water transfer tunnels, golden mussel attachment densities of 40,000 individuals/m2 mainly occurred on the portion of tunnel walls which face downwards and thus avoid sedimentation. An experiment was designed to study the effect of sediment settling on golden mussel attachment. The results showed that settling of fine sediment particles affects golden mussels by preventing them from filtering food and oxygen from water, and in this way killing them. The attachment density decreased with increased sediment deposition. Golden mussel density decreased by about 70-90% when the sedimentation rate increased by 3-6 times. Therefore, spraying with fine sediment or creating hyper-concentration of sediment water to treat golden mussels before they enter tunnels is recommended as an effective strategy for controlling golden mussel invasion and high-density bio-fouling. Key words: golden mussel invasion; bio-fouling; sediment settling; habitat; controlling strategy

Xu, Mengzhen; Wang, Zhaoyin; Bogen, Jim; Pan, Baozhu

2013-04-01

288

Impact of different benthic animals on phosphorus dynamics across the sediment-water interface.  

PubMed

As a diagenetic progress, bioturbation influences solute exchange across the sediment-water interface (SWI). Different benthic animals have various mechanical activities in sediment, thereby they may have different effects on solute exchange across the SWI. This laboratory study examined the impacts of different benthic animals on phosphorus dynamics across the SWI. Tubificid worms and Chironomidae larvae were introduced as model organisms which, based on their mechanical activities, belong to upward-conveyors and gallery-diffusers, respectively. The microcosm simulation study was carried out with a continuous flow culture system, and all sediment, water, and worms and larvae specimens were sampled from Taihu Lake, China. To compare their bioturbation effects, the same biomass (17.1 g wet weight (ww)/m2) was adopted for worms and larvae. Worms altered no oxygen penetration depth in sediment, while larvae increased the O2 penetration depth, compared to the control treatment. Their emergence also enhanced sediment O2 uptake. The oxidation of ferrous iron in pore water produced ferric iron oxyhydroxides that adsorbed soluble reactive phosphorus (SRP) from the overlying water and pore water. Larvae built obviously oxidized tubes with about 2 mm diameter and the maximum length of 6 cm in sediment, and significantly decreased ferrous iron and SRP in the pore water compared to the control and worms treatments. Worms constructed no visually-oxidized galleries in the sediment in contrast to larvae, and they did not significantly alter SRP in the pore water relative to the control treatment. The adsorption of ferric iron oxyhydroxides to SRP caused by worms and larvae inhibited SRP release from sediment. Comparatively, worms inhibited more SRP release than larvae based on the same biomass, as they successively renewed the ferric iron oxyhydroxides rich oxidation layer through their deposition. PMID:21235153

Zhang, Lei; Gu, Xiaozhi; Fanl, Chengxin; Shang, Jingge; Shen, Qiushi; Wang, Zhaode; Shen, Ji

2010-01-01

289

Sediment-water distribution of contaminants of emerging concern in a mixed use watershed.  

PubMed

This study evaluated the occurrence and distribution of 15 contaminants of emerging concern (CECs) in stream water and sediments in the Zumbro River watershed in Minnesota and compared these with sub-watershed land uses. Sixty pairs of sediment and water samples were collected across all seasons from four stream sites for over two years and analyzed for selected personal care products, pesticides, human and veterinary medications, and phytoestrogens. Spatial and temporal analyses indicate that pharmaceuticals and personal care products (urban/residential CECs) are significantly elevated in water and/or sediment at sites with greater population density (>100 people/km(2)) and percentage of developed land use (>8% of subwatershed area) than those with less population density and land area under development. Significant spatial variations of agricultural pesticides in water and sediment were detectable, even though all sites had a high percentage of agricultural land use. Seasonality in CEC concentration was observed in water but not in sediment, although sediment concentrations of three CECs did vary between years. Average measured non-equilibrium distribution coefficients exceeded equilibrium hydrophobic partitioning-based predictions for 5 of the 7 detected CECs by at least an order of magnitude. Agreement of measured and predicted distribution coefficients improved with increasing hydrophobicity and in-stream persistence. The more polar and degradable CECs showed greater variability in measured distributions across different sampling events. Our results confirm that CECs are present in urban and agricultural stream sediments, including those CECs that would typically be thought of as non-sorptive based on their log Kow values. These results and the observed patterns of sediment and water distributions augment existing information to improve prediction of CEC fate and transport, leading to more accurate assessments of exposure and risk to surface water ecosystems. PMID:25461092

Fairbairn, David J; Karpuzcu, M Ekrem; Arnold, William A; Barber, Brian L; Kaufenberg, Elizabeth F; Koskinen, William C; Novak, Paige J; Rice, Pamela J; Swackhamer, Deborah L

2015-02-01

290

Control of groundwater recharge-discharge on coupled N-processing across the sediment- water interface of floodplain sediments  

Microsoft Academic Search

From headwater agricultural streams to floodplain sloughs, denitrification is a common and environmentally important redox mediated reaction that occurs as dissolved NO3- is transported across the sediment- water interface within these systems. Factors influencing denitrification rates include carbon quality, NO3- availability, and the presence of O2. Here we present findings illustrating the influence of net groundwater recharge-discharge on nitrogen fate

D. Scott; J. W. Harvey; G. B. Noe; J. Böhlke

2007-01-01

291

Impacts of Ocean Acidification on Sediment Processes in Shallow Waters of the Arctic Ocean  

PubMed Central

Despite the important roles of shallow-water sediments in global biogeochemical cycling, the effects of ocean acidification on sedimentary processes have received relatively little attention. As high-latitude cold waters can absorb more CO2 and usually have a lower buffering capacity than warmer waters, acidification rates in these areas are faster than those in sub-tropical regions. The present study investigates the effects of ocean acidification on sediment composition, processes and sediment-water fluxes in an Arctic coastal system. Undisturbed sediment cores, exempt of large dwelling organisms, were collected, incubated for a period of 14 days, and subject to a gradient of pCO2 covering the range of values projected for the end of the century. On five occasions during the experimental period, the sediment cores were isolated for flux measurements (oxygen, alkalinity, dissolved inorganic carbon, ammonium, nitrate, nitrite, phosphate and silicate). At the end of the experimental period, denitrification rates were measured and sediment samples were taken at several depth intervals for solid-phase analyses. Most of the parameters and processes (i.e. mineralization, denitrification) investigated showed no relationship with the overlying seawater pH, suggesting that ocean acidification will have limited impacts on the microbial activity and associated sediment-water fluxes on Arctic shelves, in the absence of active bio-irrigating organisms. Only following a pH decrease of 1 pH unit, not foreseen in the coming 300 years, significant enhancements of calcium carbonate dissolution and anammox rates were observed. Longer-term experiments on different sediment types are still required to confirm the limited impact of ocean acidification on shallow Arctic sediment processes as observed in this study. PMID:24718610

Gazeau, Frédéric; van Rijswijk, Pieter; Pozzato, Lara; Middelburg, Jack J.

2014-01-01

292

Impacts of ocean acidification on sediment processes in shallow waters of the Arctic Ocean.  

PubMed

Despite the important roles of shallow-water sediments in global biogeochemical cycling, the effects of ocean acidification on sedimentary processes have received relatively little attention. As high-latitude cold waters can absorb more CO2 and usually have a lower buffering capacity than warmer waters, acidification rates in these areas are faster than those in sub-tropical regions. The present study investigates the effects of ocean acidification on sediment composition, processes and sediment-water fluxes in an Arctic coastal system. Undisturbed sediment cores, exempt of large dwelling organisms, were collected, incubated for a period of 14 days, and subject to a gradient of pCO2 covering the range of values projected for the end of the century. On five occasions during the experimental period, the sediment cores were isolated for flux measurements (oxygen, alkalinity, dissolved inorganic carbon, ammonium, nitrate, nitrite, phosphate and silicate). At the end of the experimental period, denitrification rates were measured and sediment samples were taken at several depth intervals for solid-phase analyses. Most of the parameters and processes (i.e. mineralization, denitrification) investigated showed no relationship with the overlying seawater pH, suggesting that ocean acidification will have limited impacts on the microbial activity and associated sediment-water fluxes on Arctic shelves, in the absence of active bio-irrigating organisms. Only following a pH decrease of 1 pH unit, not foreseen in the coming 300 years, significant enhancements of calcium carbonate dissolution and anammox rates were observed. Longer-term experiments on different sediment types are still required to confirm the limited impact of ocean acidification on shallow Arctic sediment processes as observed in this study. PMID:24718610

Gazeau, Frédéric; van Rijswijk, Pieter; Pozzato, Lara; Middelburg, Jack J

2014-01-01

293

CONTRIBUTION OF AMMONIA, METALS AND NONPOLAR ORGANIC COMPOUNDS TO THE TOXICITY OF SEDIMENT INTERSTITIAL WATER FROM AN ILLINOIS RIVER TRIBUTARY  

EPA Science Inventory

Toxicity of Illinois River bulk sediment, sediment interstitial (pore) water and elutriates to the oligochaete Lumbriculus variegatus, fathead minnow (Pimephales promelas) and the amphipod Hyalella azteca was compared to determine the most representative aqueous fraction for toxi...

294

Authigenic molybdenum formation in marine sediments: a link to pore water sulfide in the Santa Barbara Basin  

Microsoft Academic Search

Pore water and sediment Mo concentrations were measured in a suite of multicores collected at four sites along the northeastern flank of the Santa Barbara Basin to examine the connection between authigenic Mo formation and pore water sulfide concentration. Only at the deepest site (580 m), where pore water sulfide concentrations rise to >0.1 ?M right below the sediment water

Yan Zheng; Robert F. Anderson; Alexander van Geen; James Kuwabara

2000-01-01

295

Estimating Water Fluxes Across the Sediment-Water Interface in the Lower Merced River, California  

USGS Publications Warehouse

The lower Merced River Basin was chosen by the U.S. Geological Survey?s (USGS) National Water Quality Assessment Program (NAWQA) to be included in a national study on how hydrological processes and agricultural practices interact to affect the transport and fate of agricultural chemicals. As part of this effort, surface-water?ground-water (sw?gw) interactions were studied in an instrumented 100-m reach on the lower Merced River. This study focused on estimating vertical rates of exchange across the sediment?water interface by direct measurement using seepage meters and by using temperature as a tracer coupled with numerical modeling. Temperature loggers and pressure transducers were placed in monitoring wells within the streambed and in the river to continuously monitor temperature and hydraulic head every 15 minutes from March 2004 to October 2005. One-dimensional modeling of heat and water flow was used to interpret the temperature and head observations and deduce the sw?gw fluxes using the USGS numerical model, VS2DH, which simulates variably saturated water flow and solves the energy transport equation. Results of the modeling effort indicate that the Merced River at the study reach is generally a slightly gaining stream with small head differences (cm) between the surface water and ground water, with flow reversals occurring during high streamflow events. The average vertical flux across the sediment?water interface was 0.4?2.2 cm/day, and the range of hydraulic conductivities was 1?10 m/day. Seepage meters generally failed to provide accurate data in this high-energy system because of slow seepage rates and a moving streambed resulting in scour or burial of the seepage meters. Estimates of streambed hydraulic conductivity were also made using grain-size analysis and slug tests. Estimated hydraulic conductivity for the upstream transect determined using slug tests ranged from 40 to 250 m/day, whereas the downstream transect ranged from 10 to 100 m/day. The range in variability was a result of position along each transect. A relative percent difference was used to describe the variability in estimates of hydraulic conductivity by grain-size analysis and slug test. Variability in applied methods at the upstream transect ranged from 0 to 9 percent, whereas the downstream transect showed greater variability, with a range of 80 to 133 percent.

Zamora, Celia

2008-01-01

296

Probabilistic analysis of risks to US drinking water intakes from 1,4-dioxane in domestic wastewater treatment plant effluents.  

PubMed

The risks of 1,4-dioxane (dioxane) concentrations in wastewater treatment plant (WWTP) effluents, receiving primarily domestic wastewater, to downstream drinking water intakes was estimated using distributions of measured dioxane concentrations in effluents from 40 WWTPs and surface water dilution factors of 1323 drinking water intakes across the United States. Effluent samples were spiked with a d8 -1,4-dioxane internal standard in the field immediately after sample collection. Dioxane was extracted with ENVI-CARB-Plus solid phase columns and analyzed by GC/MS/MS, with a limit of quantification of 0.30??g/L. Measured dioxane concentrations in domestic wastewater effluents ranged from <0.30 to 3.30??g/L, with a mean concentration of 1.11?±?0.60??g/L. Dilution of upstream inputs of effluent were estimated for US drinking water intakes using the iSTREEM model at mean flow conditions, assuming no in-stream loss of dioxane. Dilution factors ranged from 2.6 to 48?113, with a mean of 875. The distributions of dilution factors and dioxane concentration in effluent were then combined using Monte Carlo analysis to estimate dioxane concentrations at drinking water intakes. This analysis showed the probability was negligible (p?=?0.0031) that dioxane inputs from upstream WWTPs could result in intake concentrations exceeding the USEPA drinking water advisory concentration of 0.35??g/L, before any treatment of the water for drinking use. PMID:23713009

Simonich, Staci Massey; Sun, Ping; Casteel, Ken; Dyer, Scott; Wernery, Dave; Garber, Kevin; Carr, Gregory; Federle, Thomas

2013-10-01

297

Summary of suspended-sediment concentration data, San Francisco Bay, California, water year 2000  

USGS Publications Warehouse

Suspended-sediment concentration data were collected in San Francisco Bay during water year 2000 (October 1, 1999?September 30, 2000). Optical backscatterance sensors and water samples were used to monitor suspended sediment at one site in Suisun Bay, three sites in San Pablo Bay, two sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at most sites. Water samples were collected periodically and were analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the electrical output of the optical backscatterance sensors. This report presents the data-collection methods and summarizes the suspended-sediment concentration data collected from October 1999 through September 2000. Calibration plots and plots of edited data for each sensor also are presented.

Buchanan, Paul A.; Ganju, Neil K.

2002-01-01

298

Soil, Groundwater, Surface Water, and Sediments of Kennedy Space Center, Florida: Background Chemical and Physical Characteristics  

NASA Technical Reports Server (NTRS)

This study documented background chemical composition of soils, groundwater, surface; water, and sediments of Kennedy Space Center. Two hundred soil samples were collected, 20 each in 10 soil classes. Fifty-one groundwater wells were installed in 4 subaquifers of the Surficial Aquifer and sampled; there were 24 shallow, 16 intermediate, and 11 deep wells. Forty surface water and sediment samples were collected in major watershed basins. All samples were away from sites of known contamination. Samples were analyzed for organochlorine pesticides, aroclors, chlorinated herbicides, polycyclic aromatic hydrocarbons (PAH), total metals, and other parameters. All aroclors (6) were below detection in all media. Some organochlorine pesticides were detected at very low frequencies in soil, sediment, and surface water. Chlorinated herbicides were detected at very low frequencies in soil and sediments. PAH occurred in low frequencies in soiL, shallow groundwater, surface water, and sediments. Concentrations of some metals differed among soil classes, with subaquifers and depths, and among watershed basins for surface water but not sediments. Most of the variation in metal concentrations was natural, but agriculture had increased Cr, Cu, Mn, and Zn.

Shmalzer, Paul A.; Hensley, Melissa A.; Mota, Mario; Hall, Carlton R.; Dunlevy, Colleen A.

2000-01-01

299

Contamination of estuarine water, biota, and sediment by halogenated organic compounds: A field study  

USGS Publications Warehouse

Studies conducted in the vicinity of an industrial outfall in the Calcasieu River estuary, Louisiana, have shown that water, bottom and suspended sediment, and four different species of biota are contaminated with halogenated organic compounds (HOC) including haloarenes. A "salting-out" effect in the estuary moderately enhanced the partitioning tendency of the contaminants into biota and sediments. Contaminant concentrations in water, suspended sediments, and biota were found to be far below the values predicted on the basis of the assumption of phase equilibria with respect to concentrations in bottom sediment. Relative concentration factors of HOC between biota (catfish) and bottom sediment increased with increasing octanol/estuarine water partition coefficients (Kow*), maximizing at log Kow* of about 5, although these ratios were considerably less than equilibrium values. In contrast, contaminant concentrations in water, biota, and suspended sediments were much closer to equilibrium values. Bioconcentration factors of HOC determined on the basis of lipid content for four different biotic species correlated reasonably well with equilibrium triolein/water partition coefficients (Ktw).

Pereira, W.E.; Rostad, C.E.; Chiou, C.T.; Brinton, T.I.; Barber, L.B., II; Demcheck, D.K.; Demas, C.R.

1988-01-01

300

Diffusive Release of Uranium from Contaminated Sediments into Capillary Fringe Pore Water  

SciTech Connect

We investigated the dynamics of U release between pore water fractions, during river stage changes from two contaminated capillary fringe sediments. Samples were from 7.0 m and 7.6 m below ground surface (bgs) in the Hanford 300 area. Sediments were packed into columns and saturated with Hanford groundwater for three to 84 days. After specified times, > 48 µm radius (calculated) sediment pores were drained, followed by draining pores to 15 µm radius. U release in the first two weeks was similar between sediments and pore sizes with a range of 4.4 to 5.6 µM U in the 14 day sample. The 7.0 m bgs sediment U declined in the larger pores to 0.22 µM at day 84, whereas the small pores released U to 6.7 µM at day 84. The 7.6 m bgs sediment released 1.4 µM on day 84, in the large pores, but continuously released U from the smaller pores (13.2 uM on day 84). The continuous release of U has resulted in a diffusion gradient from the smaller to larger pores. The observed differences in U pore-water concentrations between the two sediment samples were attributed to co-precipitation of U with carbonates. A mineral phase in the sediments was also identified as an U-carbonate species, similar to rutherfordine [UO2(CO3)].

Rod, Kenton A.; Wellman, Dawn M.; Flury, Markus; Pierce, Eric M.; Harsh, James B.

2012-09-13

301

Arsenic Redistribution Between Sediments and Water Near a Highly Contaminated Source  

SciTech Connect

Mechanisms controlling arsenic partitioning between sediment, groundwater, porewaters, and surface waters were investigated at the Vineland Chemical Company Superfund site in southern New Jersey. Extensive inorganic and organic arsenic contamination at this site (historical total arsenic >10 000 {micro}g L{sup -1} or >130 {micro}M in groundwater) has spread downstream to the Blackwater Branch, Maurice River, and Union Lake. Stream discharge was measured in the Blackwater Branch, and water samples and sediment cores were obtained from both the stream and the lake. Porewaters and sediments were analyzed for arsenic speciation as well as total arsenic, iron, manganese, and sulfur, and they indicate that geochemical processes controlling mobility of arsenic were different in these two locations. Arsenic partitioning in the Blackwater Branch was consistent with arsenic primarily being controlled by sulfur, whereas in Union Lake, the data were consistent with arsenic being controlled largely by iron. Stream discharge and arsenic concentrations indicate that despite large-scale groundwater extraction and treatment, >99% of arsenic transport away from the site results from continued discharge of high arsenic groundwater to the stream, rather than remobilization of arsenic in stream sediments. Changing redox conditions would be expected to change arsenic retention on sediments. In sulfur-controlled stream sediments, more oxic conditions could oxidize arsenic-bearing sulfide minerals, thereby releasing arsenic to porewaters and streamwaters; in iron-controlled lake sediments, more reducing conditions could release arsenic from sediments via reductive dissolution of arsenic-bearing iron oxides.

Keimowitz,A.; Zheng, Y.; Chillrud, S.; Mailloux, B.; Bok Jung, H.; Stute, M.; Simpson, H.

2005-01-01

302

Survival of daphnia magna and hyalella azteca in cadmium-spiked water and sediment  

SciTech Connect

Freshwater sediments and water were spiked with cadmium (Cd) in the laboratory, and toxicity tests were conducted with the cladoceran Daphnia magna and the amphipod Hyalella azteca to determine if Cd in the sediment would cause increased toxicity. The 48-h LC50 values for Daphnia in tests without sediment were 36, 33, 24, and 40 micrograms/L total Cd. Calculated free-ion (Cd/sup 2 +/)LC50 values for the same tests were 28, 25, 18 and 31 micrograms/L. LC50 values (48-h) determined for total Cd(uncentrifuged water sample) in the sediment-containing beakers were 252, 69, and 122 micrograms/L for Daphnia. LC50 values for dissolved Cd(centrifuged 10,000 rpm) in the sediment-containing beakers were 61, 27, and 100 micrograms/L for Daphnia. Higher total Cd LC50 values indicate that Cd adsorbed to soluble organic material was not biologically available. No significant mortality of Daphnia or Hyalella occurred in the flow-through tests in which sediment contained the same levels of Cd as in the static tests. Mortality was similar in beakers with and without Cd-spiked sediment, indicating that Cd in the sediment and adsorbed to organic materials was not available to cause increased mortality.

Nebeker, A.V.; Onjukka, S.T.; Cairns, M.A.; Krawczyk, D.F.

1986-01-01

303

Water Velocity and Bioturbation Alter Sediment Resuspension and Biogeochemistry in an Experimental Freshwater Mesocosm System  

NASA Astrophysics Data System (ADS)

Processes such as bioturbation and resuspension can affect organic matter decomposition by altering sediment redox conditions. Increased oxygen availability may, in turn, affect remineralization rates and larger scale processes such as benthic-pelagic coupling. However, relatively few studies have explicitly tested the simultaneous effects of bioturbation and water velocity on benthic biogeochemistry and sediment resuspension. Using a mesocosm system we conducted two experiments testing the effects of bioturbator identity on particulate and dissolved nutrient dynamics before and after a resuspension event (i.e. water velocity held constant at 0.12 m s-1 for 2 hr; Expt. 1) and rates of sediment resuspension with increasing water velocity (0.00 - 0.20 m s-1; Expt. 2). We manipulated bioturbator identity across four levels as sediments were undisturbed (control), manually punctured (2% of surface area), or disturbed by one of two fish species, either bluegill or catfish. For Expt. 1, the bioturbation treatments were applied for several days and measurements were made before and after the resuspension event. Initially, water column chlorophyll and total suspended sediment (TSS) concentrations were highest in the catfish treatments. Bioturbator identity did not affect the stoichiometry of TSS as strongly; C:N was unaffected by our treatments while N:P was lowest in the disturbed treatments. After the resuspension event, there was no difference in TSS concentrations or stoichiometric ratios across the bioturbation treatments. Dissolved nutrient flux rates were insensitive to the bioturbation treatments and were more strongly influenced by the resuspension event. For instance, sediment NO3- fluxes were negative (i.e. net flux into sediments) until after the resuspension event when they became positive. In Expt. 2, we gradually increased water velocity from 0.00 - 0.20 m s-1 and measured TSS concentrations only. TSS was initially highest in catfish treatments and lowest in the control treatments. However, once the water velocity was greater than 0.08 m s-1 there was no difference in TSS concentrations across the bioturbation treatments. Sediment resuspension rates were highest in control and manually disturbed treatments, possibly because these treatments had the lowest initial TSS concentrations. Overall, our results indicate that bioturbation and water velocity affect sediment nutrient dynamics and resuspension. By extension, disturbances that affect surficial sediments may also impact algal growth rates by altering nutrient and light levels. Thus it is important to consider how benthic animal communities and species identity interact with water velocity to influence sediment biogeochemical processes.

Spivak, A.; Vanni, M. J.

2010-12-01

304

Recent changes of water discharge and sediment load in the Zhujiang (Pearl River) Basin, China  

NASA Astrophysics Data System (ADS)

The paper is concerned with identifying changes in the time series of water and sediment discharge of the Zhujiang (Pearl River), China. The gradual trend test (Mann-Kendall test), and abrupt change test (Pettitt test), have been employed on annual water discharge and sediment load series (from the 1950s-2004) at nine stations in the main channels and main tributaries of the Zhujiang. Both the Mann-Kendall and Pettitt tests indicate that water discharge at all stations in the Zhujiang Basin showed no significant trend or abrupt shift. Annual water discharges are mainly influenced by precipitation variability, while the construction of reservoirs/dams in the Zhujiang Basin had little influence on water discharge. Sediment load, however, showed significant decreasing trends at some stations in the main channel of the Xijiang and Dongjiang. More stations have seen significantly decreasing trends since the 1990s. The decreasing sediment load in the Zhujiang reflects the impacts of reservoir construction in the basin. In contrast, the Liujiang, the second largest tributary of the Xijiang, has experienced a significant upward shift of sediment load around 1991 likely caused by exacerbated rock desertification in the karst regions. The annual sediment load from the Zhujiang (excluding the delta region) to the estuary has declined from 80.4 × 10 6 t averaged for the period 1957-1995 to 54.0 × 10 6 t for the period 1996-2004. More specifically, the sediment load declined steadily since the early 1990s so that in 2004 it was about one-third of the mean level of pre-90s. Water discharge and sediment load of the Zhujiang would be more affected by human activities in the future with the further reservoir developments, especially the completion of the Datengxia hydroelectric project, and an intensification of the afforestation policy in the drainage basin.

Zhang, Shurong; Lu, Xi Xi; Higgitt, David L.; Chen, Chen-Tung Arthur; Han, Jingtai; Sun, Huiguo

2008-02-01

305

Temporal variations of water and sediment fluxes in the Cointzio river basin, central Mexico  

NASA Astrophysics Data System (ADS)

The STREAMS program (Sediment TRansport and Erosion Across MountainS) was launched in 2006 to study suspended sediment dynamics in mountainous areas. Two watersheds were selected as part of the program: the Bléone river basin in the French Alps, and the Cointzio river basin (636 km2), located in the mountainous region of Michoacán, in central Mexico. The volcanic soils of the Cointzio catchment undergo important erosion processes, especially during flashflood events. Thus, a high-frequency monitoring of sediment transport is highly required. The poster presents the high-frequency database obtained from the 2008 hydrological season at the Santiago Undameo gauged station, located at the basin's outlet. Suspended Sediment Concentration (SSC) was estimated every 10 minutes by calibrating turbidity measurements with bottle sampling acquired on a double-daily basis. Water discharge time-series was approximated with continuous water-level measurements (5 minutes time-step), and a stage-discharge rating curve. Our investigation highlights the influence of sampling frequency on annual water and sediment fluxes estimate. A daily or even a weekly water-level measurement provides an unexpectedly reliable assessment of the seasonal water fluxes, with an under-estimation of about 5 % of the total flux. Concerning sediment fluxes, a high-frequency SSC survey appears to be necessary. Acquiring SSC data even twice a day leads to a significant (over 30 %) under-estimation of the seasonal sediment load. These distinct behaviors can be attributed to the fact that sediment transport almost exclusively occurs during brief night flood events, whereas exfiltration on the watershed always provides a base flow during the daily water-level measurements.

Duvert, C.; Gratiot, N.; Navratil, O.; Esteves, M.; Prat, C.; Nord, G.

2009-04-01

306

Extending the analytical window for water-soluble organic matter in sediments by aqueous Soxhlet extraction  

NASA Astrophysics Data System (ADS)

Dissolved organic matter (DOM) in marine sediments is a complex mixture of thousands of individual constituents that participate in biogeochemical reactions and serve as substrates for benthic microbes. Knowledge of the molecular composition of DOM is a prerequisite for a comprehensive understanding of the biogeochemical processes in sediments. In this study, interstitial water DOM was extracted with Rhizon samplers from a sediment core from the Black Sea and compared to the corresponding water-extractable organic matter fraction (<0.4 ?m) obtained by Soxhlet extraction, which mobilizes labile particulate organic matter and DOM. After solid phase extraction (SPE) of DOM, samples were analyzed for the molecular composition by Fourier Transform Ion-Cyclotron Resonance Mass Spectrometry (FT-ICR MS) with electrospray ionization in negative ion mode. The average SPE extraction yield of the dissolved organic carbon (DOC) in interstitial water was 63%, whereas less than 30% of the DOC in Soxhlet-extracted organic matter was recovered. Nevertheless, Soxhlet extraction yielded up to 4.35% of the total sedimentary organic carbon, which is more than 30-times the organic carbon content of the interstitial water. While interstitial water DOM consisted primarily of carbon-, hydrogen- and oxygen-bearing compounds, Soxhlet extracts yielded more complex FT-ICR mass spectra with more peaks and higher abundances of nitrogen- and sulfur-bearing compounds. The molecular composition of both sample types was affected by the geochemical conditions in the sediment; elevated concentrations of HS- promoted the early diagenetic sulfurization of organic matter. The Soxhlet extracts from shallow sediment contained specific three- and four-nitrogen-bearing molecular formulas that were also detected in bacterial cell extracts and presumably represent proteinaceous molecules. These compounds decreased with increasing sediment depth while one- and two-nitrogen-bearing molecules increased, resulting in a higher similarity of both sample types in the deep sediment. In summary, Soxhlet extraction of sediments accessed a larger and more complex pool of organic matter than present in interstitial water DOM.

Schmidt, Frauke; Koch, Boris P.; Witt, Matthias; Hinrichs, Kai-Uwe

2014-09-01

307

A conceptual model for river water and sediment dispersal in the Santa Barbara Channel, California  

USGS Publications Warehouse

The ephemeral Santa Clara River delivers large amounts of freshwater and sediment to the eastern Santa Barbara Channel during brief, episodic discharge events. This discharge into the channel was characterized here with shipboard measurements during floods of 1997 and 1998. Within approximately 1-km of the river mouth, the river discharge quickly stratifies into a freshened, turbid surface plume and a bottom nephloid layer. Observations immediately off the Santa Clara River mouth on a peak day of river discharge revealed that sediment rapidly settled from the freshened surface waters, as suspended sediment in the freshened surface plume contained only ???6% of the sediment mass expected if the sediment mixed conservatively. On the two subsequent days the reduction of sediment mass in the surface plume continued at ???50% per day. These observations suggest that river sediment undergoes rapid initial settling within ???1-km of the river mouth, followed by somewhat slower rates of settling. Although we did not measure sedimentation or bottom boundary layer processes, our mass balance results suggest that almost all of the river sediment either escapes along or deposits upon the inner shelf seabed.

Warrick, J.A.; Mertes, L.A.K.; Washburn, L.; Siegel, D.A.

2004-01-01

308

A conceptual model for river water and sediment dispersal in the Santa Barbara Channel, California  

NASA Astrophysics Data System (ADS)

The ephemeral Santa Clara River delivers large amounts of freshwater and sediment to the eastern Santa Barbara Channel during brief, episodic discharge events. This discharge into the channel was characterized here with shipboard measurements during floods of 1997 and 1998. Within approximately 1-km of the river mouth, the river discharge quickly stratifies into a freshened, turbid surface plume and a bottom nephloid layer. Observations immediately off the Santa Clara River mouth on a peak day of river discharge revealed that sediment rapidly settled from the freshened surface waters, as suspended sediment in the freshened surface plume contained only ˜6% of the sediment mass expected if the sediment mixed conservatively. On the two subsequent days the reduction of sediment mass in the surface plume continued at ˜50% per day. These observations suggest that river sediment undergoes rapid initial settling within ˜1-km of the river mouth, followed by somewhat slower rates of settling. Although we did not measure sedimentation or bottom boundary layer processes, our mass balance results suggest that almost all of the river sediment either escapes along or deposits upon the inner shelf seabed.

Warrick, Jonathan A.; Mertes, Leal A. K.; Washburn, Libe; Siegel, David A.

2004-11-01

309

Heavy Metals in Water and Sediment: A Case Study of Tembi River  

PubMed Central

This study was carried out to examine heavy metals concentration in water and sediment of upstream and downstream of the entry of the sewage to the Tembi River, Iran. Samples were collected from upstream and downstream and were analyzed for Cd, Cr, Cu, Fe, Pb, Ni, and Zn by atomic absorption spectrophotometer. The results indicated that the average concentration of the metals in water and sediment on downstream was more than that of upstream. The comparison of the mean concentrations of heavy metals in water of the Tembi River with drinking water standards and those in the water used for agriculture suggests that the mean concentration of Cu and Zn lies within the standard range for drinking water and the mean concentration of Mn, Zn, and Pb lies within the standard range of agricultural water. The highest average concentration on downstream for Pb in water and for Mn in sediment was 1.95 and 820.5?ppm, respectively. Also, the lowest average concentration on upstream was identified for Cd in water and sediment 0.07 and 10?ppm, respectively. With regard to the results, it gets clear that using the water for recreational purposes, washing, and fishing is detrimental to human health and the environment. PMID:24616738

Shanbehzadeh, Saeed; Vahid Dastjerdi, Marzieh; Hassanzadeh, Akbar; Kiyanizadeh, Toba

2014-01-01

310

Presence of pyrethroid pesticides in water and sediments of Ebro River Delta  

NASA Astrophysics Data System (ADS)

SummaryThe distribution of pyrethroid insecticides of the Ebro River Delta (NE Spain) was assessed by measuring concentrations in surface water and sediment samples. Pyrethroid extraction from water was carried out by ultrasound-assisted emulsification-extraction (UAEE), while the sediment was sonicated and cleaned up using Florisil cartridge. Method detection of limits (MLODs) for the 12 pyrethroids analyzed by gas chromatography-mass spectrometer in negative chemical ionization (GC-NCI-MS) ranged from 0.03 to 35.8 ng L -1 for water and 2.6 to 62.4 pg g -1 for sediment. Recoveries values were in the range of 47-105% for water and 51-105% for sediments, showing satisfactory robustness of the method for analyzing pyrethroids in water and sediment samples. Cypermethrin was detected in 22 water samples collected from Ebro River Delta, while deltamethrin was present only in three water samples at concentrations ranging from 0.73 ng L -1 to 57.2 ng L -1 and 2 ng L -1 to 58.8 ng L -1 for cypermethrin and deltamethrin, respectively. These concentration levels were higher than median lethal concentration (LC50) values found for deltamethrin and lower than LC50 values found for cypermethrin when short time toxic effects are considered. In sediment samples only cypermethrin was detected at concentration levels ranged from 8.27 ng g -1 to 71.9 ng g -1. These levels were higher than its LC50 values. Environmental dynamic behaviour and fate were also evaluated for cypermethrin measuring the sediment/water partition coefficient (ranging from 5.0 to 6.3) and kinetic data (half-life ranging between 13 and 50 days). Results were in good agreement to those reported in literature

Feo, M. L.; Ginebreda, A.; Eljarrat, E.; Barceló, D.

2010-11-01

311

Screening of currently used pesticides in water, sediments and biota of the Guadalquivir River Basin (Spain).  

PubMed

The occurrence of 50 currently used pesticides and their transformation products in surface and waste waters, sediment and fish in the Guadalquivir River Basin was determined in 2010 and 2011. After selective sample extraction, pesticides were identified and quantified by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The contamination profile in water and sediments is marked by the presence of organophosphorus and triazines. Transformation products were even at higher concentrations than parent pesticides. A wider range of pesticides was present in water than in sediments but none of them were detected in fish. The mean concentrations ranged from 0.2 to 13.0 ng/L in water and from 0.1 to 13.2 ng/g d.w. in sediment. The spatial distribution of most pesticides was consistent with the agricultural activities of the area or their urban applications. The waste water treatment plant effluents that impact the river are minor sources for few pesticides but for most of them run-off would be the most important contribution. The temporal distribution showed differences between both sampling campaigns related to the river flow. The low-flow produced a pesticide concentration effect, generating higher levels in water and accumulation in sediments. This forecasts a hazard in future scenarios if the current situation of the climate change and water scarcity evolves to more critical conditions highlighting the need of these monitoring studies. PMID:24140087

Masiá, Ana; Campo, Julián; Vázquez-Roig, Pablo; Blasco, Cristina; Picó, Yolanda

2013-12-15

312

A review of surface-water sediment fractions and their interactions with persistent manmade organic compounds  

USGS Publications Warehouse

This paper reviews the suspended and surficial sediment fractions and their interactions with manmade organic compounds. The objective of this review is to isolate and describe those contaminant and sediment properties that contribute to the persistence of organic compounds in surface-water systems. Most persistent, nonionic organic contaminants, such as the chlorinated insecticides and polychlorinated biphenyls (PCBs), are characterized by low water solubilities and high octanol-water partition coefficients. Consequently, sorptive interactions are the primary transformation processes that control their environmental behavior. For nonionic organic compounds, sorption is primarily attributed to the partitioning of an organic contaminant between a water phase and an organic phase. Partitioning processes play a central role in the uptake and release of contaminants by sediment organic matter and in the bioconcentration of contaminants by aquatic organisms. Chemically isolated sediment fractions show that organic matter is the primary determinant of the sorptive capacity exhibited by sediment. Humic substances, as dissolved organic matter, contribute a number of functions to the processes cycling organic contaminants. They alter the rate of transformation of contaminants, enhance apparent water solubility, and increase the carrying capacity of the water column beyond the solubility limits of the contaminant. As a component of sediment particles, humic substances, through sorptive interactions, serve as vectors for the hydrodynamic transport of organic contaminants. The capabilities of the humic substances stem in part from their polyfunctional chemical composition and also from their ability to exist in solution as dissolved species, flocculated aggregates, surface coatings, and colloidal organomineral and organometal complexes. The transport properties of manmade organic compounds have been investigated by field studies and laboratory experiments that examine the sorption of contaminants by different sediment size fractions. Field studies indicate that organic contaminants tend to sorb more to fine-grained sediment, and this correlates significantly with sediment organic matter content. Laboratory experiments have extended the field studies to a wider spectrum of natural particulates and anthropogenic compounds. Quantitation of isotherm results allows the comparison of different sediment sorbents as well as the estimation of field partition coefficients from laboratory-measured sediment and contaminant properties. Detailed analyses made on the basis of particle-size classes show that all sediment fractions need to be considered in evaluating the fate and distribution of manmade organic compounds. This conclusion is based on observations from field studies and on the variety of natural organic sorbents that demonstrate sorptive capabilities in laboratory isotherm experiments.

Witkowski, P.J.; Smith, J.A.; Fusillo, T.V.; Chiou, C.T.

1987-01-01

313

Microscale Modelling of Water and Gas-Water Flows in Subsea Sand Sediment  

NASA Astrophysics Data System (ADS)

Methane hydrate is a promising energy resource in the near future. Its production is a current hot topic and flow of methane gas with water in sediment sand layer is very important to predict the production rate. In this study, permeability of microscale sand layer was numerically simulated by a three-dimensional lattice Boltzmann method. Shapes of real sands were extracted by series expansion of spherical harmonics using CT-scan images of real subsea core samples. These extracted sands were located in a cubic lattice domain by a simulated annealing method to fit to given porosities. Pressure difference was imposed at the both end faces of the domain to flow water and methane gas. By this simulation, permeability of water phase and water-gas two-phase flow were analysed and compared well with existing models. This work was financially supported by Japan's Methane Hydrate R&D Program planned by Ministry of Economy, Trade and Industry (METI). 3D image of an extracted frame-sand grain Distribution of gas and water phases in computational domain for Sw=0.80

Sato, T.; Sugita, T.; Hirabayashi, S.; Nagao, J.; Jin, Y.; Kiyono, F.

2009-12-01

314

Sequestration of priority pollutant PAHs from sediment pore water employing semipermeable membrane devices  

USGS Publications Warehouse

Semipermeable membrane devices (SPMDs) were employed to sample sediment pore water in static exposure studies under controlled laboratory conditions using (control pond and formulated) sediments fortified with 15 priority pollutant polycyclic aromatic hydrocarbons (PPPAHs). The sediment fortification level of 750 ng/g was selected on the basis of what might be detected in a sediment sample from a contaminated area. The sampling interval consisted of 0, 4, 7, 14, and 28 days for each study. The analytical methodologies, as well as the extraction and sample cleanup procedures used in the isolation, characterization, and quantitation of 15 PPPAHs at different fortification levels in SPMDs, water, and sediment were reported previously (Williamson, M.S. Thesis, University of Missouri - Columbia, USA; Williamson et al., Chemosphere (This issue - PII: S0045-6535(02)00394-6)) and used for this project. Average (mean) extraction recoveries for each PPPAH congener in each matrix are reported and discussed. No procedural blank extracts (controls) were found to contain any PPPAH residues above the method quantitation limit, therefore, no matrix interferences were detected. The focus of this publication is to demonstrate the ability to sequester environmental contaminants, specifically PPPAHs, from sediment pore water using SPMDs and two different types of fortified sediment.

Williamson, K.S.; Petty, J.D.; Huckins, J.N.; Lebo, J.A.; Kaiser, E.M.

2002-01-01

315

Mercury cycling in stream ecosystems. 2. Benthic methylmercury production and bed sediment - Pore water partitioning  

USGS Publications Warehouse

Mercury speciation, controls on methylmercury (MeHg) production, and bed sediment - pore water partitioning of total Hg (THg) and MeHg were examined in bed sediment from eight geochemically diverse streams where atmospheric deposition was the predominant Hg input. Across all streams, sediment THg concentrations were best described as a combined function of sediment percent fines (%fines; particles < 63 ??m) and organic content. MeHg concentrations were best described as a combined function of organic content and the activity of the Hg(II)-methylating microbial community and were comparable to MeHg concentrations in streams with Hg inputs from industrial and mining sources. Whole sediment tin-reducible inorganic reactive Hg (Hg(II)R) was used as a proxy measure for the Hg(II) pool available for microbial methylation. In conjunction with radiotracer-derived rate constants of 203Hg(II) methylation, Hg(II)R was used to calculate MeHg production potential rates and to explain the spatial variability in MeHg concentration. The %Hg(II)R (of THg) was low (2.1 ?? 5.7%) and was inversely related to both microbial sulfate reduction rates and sediment total reduced sulfur concentration. While sediment THg concentrations were higher in urban streams, %MeHg and %Hg(II)R were higher in nonurban streams. Sediment pore water distribution coefficients (log Kd's) for both THg and MeHg were inversely related to the log-transformed ratio of pore water dissolved organic carbon (DOC) to bed sediment %fines. The stream with the highest drainage basin wetland density also had the highest pore water DOC ?? 2009 American Chemical Society.

Marvin-DiPasquale, M.; Lutz, M.A.; Brigham, M.E.; Krabbenhoft, D.P.; Aiken, G.R.; Orem, W.H.; Hall, B.D.

2009-01-01

316

Contaminants in surface water and sediments near the Tynagh silver mine site, County Galway, Ireland.  

PubMed

A former silver mine in Tynagh, Co. Galway, Ireland is one of the most contaminated mine sites in Europe with maximum concentrations of Zn, As, Pb, Mn, Ni, Cu, and Cd far exceeding guideline values for water and sediment. The aims of this research were to 1) further assess the contamination, particularly metals, in surface water and sediment around the site, and 2) determine if the contamination has increased 10years after the Environmental Protection Agency Ireland (EPAI) identified off-site contamination. Site pH is alkaline to neutral because CaCO3-rich sediment and rock material buffer the exposed acid generating sulphide-rich ore. When this study was compared to the previous EPAI study conducted 10years earlier, it appeared that further weathering of exposed surface sediment had increased concentrations of As and other potentially toxic elements. Water samples from the tailings ponds and adjacent Barnacullia Stream had concentrations of Al, Cd, Mn, Zn and Pb above guideline values. Lead and Zn concentrations from the tailings pond sediment were 16 and 5 times higher, respectively, than concentrations reported 10years earlier. Pb and Zn levels in most sediment samples exceeded the Expert Group (EGS) guidelines of 1000 and 5000mg/kg, respectively. Arsenic concentrations were as high as 6238mg/kg in the tailings ponds sediment, which is 62 and 862 times greater than the EGS and Canadian Soil Quality Guidelines (CSQG), respectively. Cadmium, Cu, Fe, Mn, Pb and Zn concentrations in water and sediment were above guideline values downstream of the site. Additionally, Fe, Mn and organic matter (OM) were strongly correlated and correlated to Zn, Pb, As, Cd, Cu and Ni in stream sediment. Therefore, the nearby Barnacullia Stream is also a significant pathway for contaminant transport to downstream areas. Further rehabilitation of the site may decrease the contamination around the area. PMID:25634731

O'Neill, A; Phillips, D H; Bowen, J; Sen Gupta, B

2015-04-15

317

Screening toxicity evaluation of Wheeler Reservoir sediments using juvenile freshwater mussels (Anodonta imbecillis say) exposed to sediment interstitial water  

SciTech Connect

Reservoir sediments (porewater) near several wastewater outfalls at Decatur, Alabama, were screened for acute (9-day) toxicity to 8-day old freshwater mussels. Sampling locations corresponded to four of five sites previously surveyed by the Alabama Wildlife Federation and Alabama mussel divers. A site located on the opposite (north) overbank where mussels are abundant was chosen as the study control. Reference sediments from an outdoor channel at TVA's Aquatic Research Laboratory (ARL) with flow-through Wheeler Reservoir water and from a downstream (Kentucky) reservoir were included in the study for comparative purposes. Toxicity was observed at two of the Decatur sites, and in the ARL channel. Sediments from the other two Decatur sites, the north overbank (control), and Kentucky Reservoir were not toxic to the test animals. Toxicity at station Alpha and from the ARL channel was correlated with un-ionized ammonia present in porewater during the test. Toxicity at station Delta was above the level explained by the regression model examined for ammonia. The site at Decatur having the greatest toxicity and ammonia concentration (Alpha) was located in the Dry Branch Embayment. Elevated ammonia in sediment collected from ARL was attributed to natural events. 13 refs., 4 figs., 6 tabs.

Wade, D.C.

1990-12-01

318

Analytical assessment about the simultaneous quantification of releasable pharmaceutical relevant inorganic nanoparticles in tap water and domestic waste water.  

PubMed

For pharmaceutical applications, the use of inorganic engineered nanoparticles is of growing interest while silver (Ag) and gold (Au) are the most relevant elements. A few methods were developed recently but the validation and the application testing were quite limited. Therefore, a routinely suitable multi element method for the identification of nanoparticles of different sizes below 100nm and elemental composition by applying asymmetric flow field flow fraction (AF4) - inductively coupled plasma mass spectrometry (ICPMS) is developed. A complete validation model of the quantification of releasable pharmaceutical relevant inorganic nanoparticles based on Ag and Au is presented for the most relevant aqueous matrices of tap water and domestic waste water. The samples are originated from locations in the Netherlands and it is of great interest to study the unwanted presence of Ag and Au as nanoparticle residues due to possible health and environmental risks. During method development, instability effects are observed for 60nm and 70nm Ag ENPs with different capping agents. These effects are studied more closely in relation to matrix effects. Besides the methodological aspects, the obtained analytical results and relevant performance characteristics (e.g. measuring range, limit of detection, repeatability, reproducibility, trueness, and expanded uncertainty of measurement) are determined and discussed. For the chosen aqueous matrices, the results of the performance characteristics are significantly better for Au ENPs in comparison to Ag ENPs; e.g. repeatability and reproducibility are below 10% for all Au ENPs respectively maximal 27% repeatability for larger Ag ENPs. The method is a promising tool for the simultaneous determination of releasable pharmaceutical relevant inorganic nanoparticles. PMID:24856919

Krystek, Petra; Bäuerlein, Patrick S; Kooij, Pascal J F

2015-03-15

319

Land subsidence in Yunlin, Taiwan, due to Agricultural and Domestic Water Use  

NASA Astrophysics Data System (ADS)

Subsidence in a layered aquifer is caused by groundwater excess extraction and results in complicated problems in Taiwan. Commonly, responsibility to subsidence for agricultural and domestic water users is difficulty to identify due to the lack of quantitative evidences. An integrated model was proposed to analyze subsidence problem. The flow field utilizes analytical solution for pumping in a layered system from Neuman and Witherspoon (1969) to calculate the head drawdown variation. The subsidence estimation applies Terzaghi (1943) one-dimensional consolidation theory to calculate the deformation in each layer. The proposed model was applied to estimate land subsidence and drawdown variation at the Yuanchang Township of Yunlin County in Taiwan. Groundwater data for dry-season periods were used for calibration and validation. Seasonal effect in groundwater variation was first filtered out. Dry-season pumping effect on land subsidence was analyzed. The results show that multi-layer pumping contributes more in subsidence than single-layer pumping on the response of drawdown and land subsidence in aquifer 2 with a contribution of 97% total change at Yuanchang station. Pumping in aquifer 2 contributes more significant than pumping in aquifer 3 to cause change in drawdown and land subsidence in aquifer 2 with a contribution of 70% total change at Yuanchang station. Larger area of subsidence in Yuanchang Township was attributed pumping at aquifer 2 while pumping at aquifer 3 results in significant subsidence near the well field. The single-layer user contributes most area of subsidence but the multi-layer user generates more serious subsidence.

Hsu, K.; Lin, P.; Lin, Z.

2013-12-01

320

Analytical Methods for Measuring Mercury in Water, Sediment and Biota  

SciTech Connect

Mercury (Hg) exists in a large number of physical and chemical forms with a wide range of properties. Conversion between these different forms provides the basis for mercury's complex distribution pattern in local and global cycles and for its biological enrichment and effects. Since the 1960’s, the growing awareness of environmental mercury pollution has stimulated the development of more accurate, precise and efficient methods of determining mercury and its compounds in a wide variety of matrices. During recent years new analytical techniques have become available that have contributed significantly to the understanding of mercury chemistry in natural systems. In particular, these include ultra sensitive and specific analytical equipment and contamination-free methodologies. These improvements allow for the determination of total mercury as well as major species of mercury to be made in water, sediments and soils, and biota. Analytical methods are selected depending on the nature of the sample, the concentration levels of mercury, and what species or fraction is to be quantified. The terms “speciation” and “fractionation” in analytical chemistry were addressed by the International Union for Pure and Applied Chemistry (IUPAC) which published guidelines (Templeton et al., 2000) or recommendations for the definition of speciation analysis. "Speciation analysis is the analytical activity of identifying and/or measuring the quantities of one or more individual chemical species in a sample. The chemical species are specific forms of an element defined as to isotopic composition, electronic or oxidation state, and/or complex or molecular structure. The speciation of an element is the distribution of an element amongst defined chemical species in a system. In case that it is not possible to determine the concentration of the different individual chemical species that sum up the total concentration of an element in a given matrix, meaning it is impossible to determine the speciation, it is a useful practice to do fractionation instead. Fractionation is the process of classification of an analyte or a group of analytes from a certain sample according to physical (e.g. size, solubility) or chemical (e.g. bonding, reactivity) properties."

Lasorsa, Brenda K.; Gill, Gary A.; Horvat, Milena

2012-06-07

321

Responses of wetland plants to effluents in water and sediment  

SciTech Connect

Responses of two wetland vascular plants, Echinochloa crusgalli and Sesbania macrocarpa, exposed to effluents from a coke plant, a pulp mill, a wastewater treatment plant, and the herbicide, hexazinone, were measured in three types of tests: seed germination and early growth, seedling survival and growth in hydroponic culture, and seedling survival and growth in sand and synthetic sediments with clay, silt, and sand, 3, 5, 7.5, or 10% organic contents. There was no effect of effluents or herbicide on germination and survival was affected only by the herbicide. When compared to controls, growth rates were reduced significantly in all tests except for E. crusgalli exposed to effluent from a wastewater treatment plant. There, the effluent stimulated growth in sediments. Increasing concentrations of organic matter in sediments had little effect on toxicity of effluents, but did cause reduced effects of hexazinone.

Walsh, G.E.; Weber, D.E.; Nguyen, M.T.; Esry, L.K.

1991-01-01

322

Microbial transformations of arsenic: Mobilization from glauconitic sediments to water  

USGS Publications Warehouse

In the Inner Coastal Plain of New Jersey, arsenic (As) is released from glauconitic sediment to carbon- and nutrient-rich shallow groundwater. This As-rich groundwater discharges to a major area stream. We hypothesize that microbes play an active role in the mobilization of As from glauconitic subsurface sediments into groundwater in the Inner Coastal Plain of New Jersey. We have examined the potential impact of microbial activity on the mobilization of arsenic from subsurface sediments into the groundwater at a site on Crosswicks Creek in southern New Jersey. The As contents of sediments 33–90 cm below the streambed were found to range from 15 to 26.4 mg/kg, with siderite forming at depth. Groundwater beneath the streambed contains As at concentrations up to 89 ?g/L. Microcosms developed from site sediments released 23 ?g/L of As, and active microbial reduction of As(V) was observed in microcosms developed from site groundwater. DNA extracted from site sediments was amplified with primers for the 16S rRNA gene and the arsenate respiratory reductase gene, arrA, and indicated the presence of a diverse anaerobic microbial community, as well as the presence of potential arsenic-reducing bacteria. In addition, high iron (Fe) concentrations in groundwater and the presence of iron-reducing microbial genera suggests that Fe reduction in minerals may provide an additional mechanism for release of associated As, while arsenic-reducing microorganisms may serve to enhance the mobility of As in groundwater at this site.

Mumford, Adam C.; Barringer, Julia L.; Benzel, William M.; Reilly, Pamela A.; Young, L.Y.

2012-01-01

323

Mercury and methylmercury contents in mine-waste calcine, water, and sediment collected from the Palawan Quicksilver mine, Philippines  

USGS Publications Warehouse

The Palawan Quicksilver mine, Philippines, produced about 2,900 t of mercury during mining of cinnabar ore from 1953 to 1976. More than 2,000,000 t of mine-waste calcines (retorted ore) were produced during mining, much of which were used to construct a jetty in nearby Honda Bay. Since 1995, high Hg contents have been found in several people living near the mine, and 21 of these people were treated for mercury poisoning. Samples of mine-waste calcine contain high total Hg concentrations ranging from 43-660 ??g/g, whereas total Hg concentrations in sediment samples collected from a mine pit lake and local stream vary from 3.7-400 ??g/g. Mine water flowing through the calcines is acidic, pH 3.1-4.3, and total Hg concentrations ranging from 18-31 ??g/l in this water significantly exceed the 1.0-??g/l drinking water standard for Hg recommended by the World Health Organization (WHO). Total Hg contents are generally lower in water samples collected from surrounding domestic wells, the mine pit lake, Honda Bay, and the nearby stream, varying from 0.008-1.4 ??g/l. Methylmercury concentrations in water draining mine calcines range from <0.02-1.4 ng/l, but methylmercury is highest in the pit lake water, ranging from 1.7-3.1 ng/l. Mercury methylation at the Palawan mine is similar to or higher than that found in other mercury mines worldwide. Much of the methylmercury generated in Palawan mine-waste calcines and those in Honda Bay is transferred to water, and then to marine fish and seafood. A food source pathway of Hg to humans is most likely in this coastal, high fish-consuming population.

Gray, J.E.; Greaves, I.A.; Bustos, D.M.; Krabbenhoft, D.P.

2003-01-01

324

Field Evaluation Of Arsenic Transport Across The Ground Water/Surface Water Interface: Speciation In Sediment Material  

EPA Science Inventory

The solubility and mobility of arsenic in ground water are influenced by a variety of processes in the northeastern US subjective to geogenic and anthropogenic sources. This presentation will discuss the speciation of arsenic in sediment profiles resulting from ground water disc...

325

Sediment microbial communities in Great Boiling Spring are controlled by temperature and distinct from water communities  

PubMed Central

Great Boiling Spring is a large, circumneutral, geothermal spring in the US Great Basin. Twelve samples were collected from water and four different sediment sites on four different dates. Microbial community composition and diversity were assessed by PCR amplification of a portion of the small subunit rRNA gene using a universal primer set followed by pyrosequencing of the V8 region. Analysis of 164?178 quality-filtered pyrotags clearly distinguished sediment and water microbial communities. Water communities were extremely uneven and dominated by the bacterium Thermocrinis. Sediment microbial communities grouped according to temperature and sampling location, with a strong, negative, linear relationship between temperature and richness at all taxonomic levels. Two sediment locations, Site A (87–80?°C) and Site B (79?°C), were predominantly composed of single phylotypes of the bacterial lineage GAL35 (p?=36.1%), Aeropyrum (p?=16.6%), the archaeal lineage pSL4 (p?=15.9%), the archaeal lineage NAG1 (p?=10.6%) and Thermocrinis (p?=7.6%). The ammonia-oxidizing archaeon ‘Candidatus Nitrosocaldus' was relatively abundant in all sediment samples <82?°C (p?=9.51%), delineating the upper temperature limit for chemolithotrophic ammonia oxidation in this spring. This study underscores the distinctness of water and sediment communities in GBS and the importance of temperature in driving microbial diversity, composition and, ultimately, the functioning of biogeochemical cycles. PMID:23235293

Cole, Jessica K; Peacock, Joseph P; Dodsworth, Jeremy A; Williams, Amanda J; Thompson, Daniel B; Dong, Hailiang; Wu, Geng; Hedlund, Brian P

2013-01-01

326

Sediment microbial communities in Great Boiling Spring are controlled by temperature and distinct from water communities.  

PubMed

Great Boiling Spring is a large, circumneutral, geothermal spring in the US Great Basin. Twelve samples were collected from water and four different sediment sites on four different dates. Microbial community composition and diversity were assessed by PCR amplification of a portion of the small subunit rRNA gene using a universal primer set followed by pyrosequencing of the V8 region. Analysis of 164 178 quality-filtered pyrotags clearly distinguished sediment and water microbial communities. Water communities were extremely uneven and dominated by the bacterium Thermocrinis. Sediment microbial communities grouped according to temperature and sampling location, with a strong, negative, linear relationship between temperature and richness at all taxonomic levels. Two sediment locations, Site A (87-80 °C) and Site B (79 °C), were predominantly composed of single phylotypes of the bacterial lineage GAL35 (\\[pmacr]=36.1%), Aeropyrum (\\[pmacr]=16.6%), the archaeal lineage pSL4 (\\[pmacr]=15.9%), the archaeal lineage NAG1 (\\[pmacr]=10.6%) and Thermocrinis (\\[pmacr]=7.6%). The ammonia-oxidizing archaeon 'Candidatus Nitrosocaldus' was relatively abundant in all sediment samples <82 °C (\\[pmacr]=9.51%), delineating the upper temperature limit for chemolithotrophic ammonia oxidation in this spring. This study underscores the distinctness of water and sediment communities in GBS and the importance of temperature in driving microbial diversity, composition and, ultimately, the functioning of biogeochemical cycles. PMID:23235293

Cole, Jessica K; Peacock, Joseph P; Dodsworth, Jeremy A; Williams, Amanda J; Thompson, Daniel B; Dong, Hailiang; Wu, Geng; Hedlund, Brian P

2013-04-01

327

Grazing Land Management Strongly Controls Water Quality, Sediment and Channel Dynamics in Tallgrass Prairie Headwater Networks  

NASA Astrophysics Data System (ADS)

In the prairie remnants of North America, watershed sediment regimes are heavily influenced by livestock grazing practices. Despite dramatic declines in stream water quality and ecosystem function concomitant with increasing gazing pressures, there have been no studies to quantitatively assess the relationship between various grazing treatments and sediment production in natural grassland ecosystems. In this study, we evaluate suspended sediment transport and channel morphology in the Flint Hills physiographic province using a paired whole-watershed approach, including 2 replicates of high density cattle grazing, 2 replicates of low density cattle grazing, 3 replicates of bison grazing and 3 replicates of no grazing. As expected, results demonstrate that cattle grazing operations increase e-coli, sediment concentrations and increase channel width. However, no significant differences in e-coli, suspended sediment dynamics or channel geomorphology were found between bison grazed and ungrazed watersheds.

Grudzinski, B. G.; Daniels, M. D.

2013-12-01

328

Enzyme activities in the water column and in shallow permeable sediments from the northeastern Gulf of Mexico  

NASA Astrophysics Data System (ADS)

The activities of extracellular enzymes that initiate the microbial remineralization of high molecular weight organic matter were investigated in the water column and sandy surface sediments at two sites in the northeastern Gulf of Mexico. Six fluorescently labeled polysaccharides were hydrolyzed rapidly in the water column as well as in permeable sediments. This result contrasts with previous studies carried out in environments dominated by fine-grained muds, in which the spectrum of enzymes active in the water column is quite limited compared to that of the underlying sediments. Extracts of Spirulina, Isochrysis, and Thalassiosira were also used to measure hydrolysis rates in water from one of the sites. Rates of hydrolysis of the three plankton extracts were comparable to those of the purified polysaccharides. The broad spectrum and rapid rates of hydrolysis observed in the water column at both sites in the northeastern Gulf of Mexico may be due to the permeable nature of the sediments. Fluid flux through the sediments is sufficiently high that the entire 1.5 m deep water column could filter though the sediments on timescales of a few days to two weeks. Movement of water through sediments may also transport dissolved enzymes from the sediment into the water column, enhancing the spectrum as well as the rate of water column enzymatic activities. Such interaction between the sediments and water column would permit water column microbial communities to access high molecular weight substrates that might otherwise remain unavailable as substrates.

Arnosti, C.; Ziervogel, K.; Ocampo, L.; Ghobrial, S.

2009-09-01

329

Metal ions in water and sediments of the Pom-Atasta Lagoon, Mexico  

SciTech Connect

Temperature, salinity, turbidity, total suspended solids (TSS), pH, and dissolved oxygen were measured in the surface water of the Pom-Atasta Lagoon at 15 stations during 5 sampling events from September 1996--May 1997. Concentrations of Cu, Cd, Ni, Zn, Pb, Cr, Ag, Fe, Co, and Ba were also determined in the water and sediments at 15 stations during the study period. The values of salinity, turbidity, and TSS were related to the inputs of river water into the lagoon. Metals in the water and sediments showed no spatial variation. Seasonality in the concentrations of Cu, Zn, Ag, and Ba in the water was found and may be related to the resuspension of sediments in the lagoon. The concentrations of metals in sediments did not give significant seasonal variation. Metals in sediments were not correlated with the iron, suggesting an anthropogenic source of metals in the Pom-Atasta Lagoon. The concentrations of dissolved Pb were above the value recommended by the National Water Commission of Mexico.

Vazquez, G.F.; Enciso, G.; Morales, J.W. [UNAM, Distrito Federal (Mexico). Instituto de Ciencias Del Mar y Limnologia] [UNAM, Distrito Federal (Mexico). Instituto de Ciencias Del Mar y Limnologia; Sharma, V.K. [Texas A and M Univ., Corpus Christi, TX (United States). Dept. of Chemistry] [Texas A and M Univ., Corpus Christi, TX (United States). Dept. of Chemistry; Nischt, S.L.; Domingo, G.L. [PEMEX, Campeche (Mexico)] [PEMEX, Campeche (Mexico)

1999-07-01

330

Eutrophication in the northern Adriatic Sea: Pore water and sediment studies  

SciTech Connect

The northern Adriatic Sea has been plagued by problems of eutrophication. This area is relatively shallow (maximum depth = 60m), becoming stratified during the summer months which inhibits oxygen transport to bottom waters. Anthropogenic nutrient loading in rivers entering the northern Adriatic (Po River being the largest) has increased nutrient input to this system and stimulated algal growth. Cores were collected for studies of pore water and solid phase chemistry at 6 stations in this region. [sup 210]Pb was used to constrain sediment accumulation rates and a range of 0-0.5 cm/yr was determined at different stations. Excess [sup 234]Th was only found in the upper 1-2 cm, suggesting that bioturbation is largely restricted to shallow depths. Pore water profiles show evidence of irrigation, and mean diffusive fluxes for oxygen, silica phosphate and ammonia are generally 20-90% of the fluxes obtained from benthic chamber measurements. This is consistent with previous work in this area in which studies of radon fluxes indicated that irrigation plays an important role in sediment-water exchange. Pore water profiles in the northern portion of the study area (near the Po River Delta) were markedly different than profiles in the south; sediments in the north are substantially more acidic and have high concentrations of dissolved iron and phosphate. From the alkalinity vs. TCO[sub 2] relationship in sediment pore waters it appears that differences in reactions involving the reduction of iron oxides and the exchange of magnesium for iron in clays are responsible for this regional difference in pore water properties. Sediments close to the Po apparently undergo more iron-magnesium exchange, while more distal sediments are limited in their ability to do so. Other pore water observations are limited in their ability to do so. Other pore water observations and trends regarding the shape of the silica profiles (which show shallow maxima) will be discussed.

Hammond, D.E.; Berelson, W.M. (Univ. of Southern California, Los Angeles (United States)); Giordani, P.; Langone, L.; Frignani, M.; Ravaioli, M. (Inst. di Geologia Marina, CNR, Bologna (Italy))

1990-01-09

331

Calibration and application of an automated seepage meter for monitoring water flow across the sediment-water interface.  

PubMed

The advective flow of sediment pore water is an important parameter for understanding natural geochemical processes within lake, river, wetland, and marine sediments and also for properly designing permeable remedial sediment caps placed over contaminated sediments. Automated heat pulse seepage meters can be used to measure the vertical component of sediment pore water flow (i.e., vertical Darcy velocity); however, little information on meter calibration as a function of ambient water temperature exists in the literature. As a result, a method with associated equations for calibrating a heat pulse seepage meter as a function of ambient water temperature is fully described in this paper. Results of meter calibration over the temperature range 7.5 to 21.2 ° C indicate that errors in accuracy are significant if proper temperature-dependence calibration is not performed. The proposed calibration method allows for temperature corrections to be made automatically in the field at any ambient water temperature. The significance of these corrections is discussed. PMID:25754860

Zhu, Tengyi; Fu, Dafang; Jenkinson, Byron; Jafvert, Chad T

2015-04-01

332

Suspended sediment source areas and future climate impact on soil erosion and sediment yield in a New York City water supply watershed, USA  

NASA Astrophysics Data System (ADS)

High suspended sediment loads and the resulting turbidity can impact the use of surface waters for water supply and other designated uses. Changes in fluvial sediment loads influence material fluxes, aquatic geochemistry, water quality, channel morphology, and aquatic habitats. Therefore, quantifying spatial and temporal patterns in sediment loads is important both for understanding and predicting soil erosion and sediment transport processes as well as watershed-scale management of sediment and associated pollutants. A case study from the 891 km2 Cannonsville watershed, one of the major watersheds in the New York City water supply system is presented. The objective of this study was to apply Soil and Water Assessment Tool-Water Balance (SWAT-WB), a physically based semi-distributed model to identify suspended sediment generating source areas under current conditions and to simulate potential climate change impacts on soil erosion and suspended sediment yield in the study watershed for a set of future climate scenarios representative of the period 2081-2100. Future scenarios developed using nine global climate model (GCM) simulations indicate a sharp increase in the annual rates of soil erosion although a similar result in sediment yield at the watershed outlet was not evident. Future climate related changes in soil erosion and sediment yield appeared more significant in the winter due to a shift in the timing of snowmelt and also due to a decrease in the proportion of precipitation received as snow. Although an increase in future summer precipitation was predicted, soil erosion and sediment yield appeared to decrease owing to an increase in soil moisture deficit and a decrease in water yield due to increased evapotranspiration.

Mukundan, Rajith; Pradhanang, Soni M.; Schneiderman, Elliot M.; Pierson, Donald C.; Anandhi, Aavudai; Zion, Mark S.; Matonse, Adão H.; Lounsbury, David G.; Steenhuis, Tammo S.

2013-02-01

333

Sedimentation patterns on a cold-water coral mound off Mauritania  

NASA Astrophysics Data System (ADS)

An unconformity-bound glacial sequence (135 cm thick) of a coral-bearing sediment core collected from the flank of a cold-water coral mound in the Banda Mound Province off Mauritania was analysed. In order to study the relation between coral framework growth and its filling by hemipelagic sediments, U-series dates obtained from the cold-water coral species Lophelia pertusa were compared to 14C dates of planktonic foraminifera of the surrounding matrix sediments. The coral ages, ranging from 45.1 to 32.3 ka BP, exhibit no clear depositional trend, while on the other hand the 14C dates of the matrix sediment provide ages within a much narrower time window of <3000 yrs (34.6-31.8 cal ka BP), corresponding to the latest phase of the coral growth period. In addition, high-resolution computer tomography data revealed a subdivision of the investigated sediment package into three distinct parts, defined by the portion and fragmentation of corals and associated macrofauna as well as in the density of the matrix sediments. Grain size spectra obtained on the matrix sediments show a homogeneous pattern throughout the core sediment package, with minor variations. These features are interpreted as indicators of redeposition. Based on the observed structures and the dating results, the sediments were interpreted as deposits of a mass wasting event, namely a debris flow. During this event, the sediment unit must have been entirely mixed; resulting in averaging of the foraminifera ages from the whole unit and giving randomly distributed coral ages. In this context, for the first time mass wasting is proposed to be a substantial process of mound progradation by exporting material from the mound top to the flanks. Hence, it may not only be an erosional feature but also widening the base of the mound, thus allowing further vertical mound growth.

Eisele, Markus; Frank, Norbert; Wienberg, Claudia; Titschack, Jürgen; Mienis, Furu; Beuck, Lydia; Tisnerat-Laborde, Nadine; Hebbeln, Dierk

2014-01-01

334

Assessment of arsenic concentrations in domestic well water, by town, in Maine 2005-09  

USGS Publications Warehouse

Prior studies have established that approximately 10 percent of domestic wells in Maine have arsenic levels greater than the U.S. Environmental Protection Agency maximum contaminant limit (10 micrograms per liter (ug/L)). Of even greater concern are multiple discoveries of wells with very high arsenic levels (> 500 ug/L) in several areas of the State. A study was initiated to assist the Maine Center for Disease Control and Prevention (ME-CDC) in developing a better understanding of the statewide spatial occurrence of wells with elevated arsenic levels at the individual town level, identify areas of the State that should be targeted for increased efforts to promote well-water testing, and generate data for potential use in predicting areas of the State likely to have very high levels of arsenic. The State's Health and Environmental and Testing Laboratory (HETL) annually analyzes samples from thousands of domestic wells for arsenic. Results of arsenic analyses of domestic well water submitted to the HETL from 2005 to 2009 were screened and organized, by town, in order to summarize the results for all towns with samples submitted to the HETL. In order to preserve the privacy of well owners, the screening and organization of samples was conducted in the offices of the ME-CDC, following applicable Maine and United States laws, rules, and privacy policies. After screening, the database contained samples from 531 towns in Maine and from 11,111 individual wells. Of those towns, 385 had samples from 5 or more individual wells, 174 towns had samples from 20 or more individual wells, and 49 towns had samples from 60 or more wells. These samples, because they were submitted by homeowners and were not part of a random sample, may not be representative of all wells in a given area. The minimum, maximum, and median arsenic values for the towns with five or more samples were calculated, and the maximum and median values were mapped for the State. The percentages of samples exceeding 10, 50, 100, and 500 ug/L were calculated for the 174 towns with 20 or more sampled wells, and statewide maps were prepared for each of these categories. More than 25 percent of the sampled wells in 44 towns exceeded 10 ug/L. Many fewer towns had wells with samples that exceeded the 50, 100, or 500 ug/L categories. For 19 towns, more than 10 percent of the sampled wells had arsenic concentrations that exceeded 50 ug/L, and in 45 towns, 1 percent or more exceeded 100 ug/L. Of these, Surry in Hancock County had 120 wells tested, and 23 percent of those wells had arsenic concentrations that exceeded 100 ug/L, which is a much higher rate than for other towns. In only four towns (Danforth in Washington County, Surry and Blue Hill in Hancock County, and Woolwich in Sagadahoc County), 1 percent or more of the sampled wells had arsenic concentrations greater than 500 ug/L during 2005-09. The distribution of high arsenic concentrations in wells follows some geographic patterns, which are generally geologically controlled. There are clusters or belts of towns with high arsenic concentrations (> 50 ug/L), such as in southern coastal areas, the Kennebec County area, and towns along the central coastal part of Maine. In contrast, there are areas of the State with low arsenic concentrations, such as the northernmost towns, as well as towns in the western and west-central areas. There appear to be three distinct large-scale areas of high concentrations of arsenic in groundwater-one in southern coastal areas, one in central Kennebec County, and one in the town of Ellsworth (Hancock County) and the surrounding areas. In addition, several smaller clusters of isolated high concentrations of arsenic in groundwater exist. Earlier testing has identified other clusters of very high arsenic concentrations in groundwater in the towns of Northport, Buxton/Hollis, and Waldoboro, but those samples were collected before 2005 and did not factor in this analysis.

Nielsen, M.G.; Lombard, P.J.; Schalk, L.F.

2010-01-01

335

WATER AND SEDIMENT MANAGEMENT FOR THE BLUE NILE BASIN  

Microsoft Academic Search

The sediment yield of rivers is often sensitive to changes in catchments land use and human activities. Such an impact is most likely to be demonstrated at a restricted spatial scale, particularly in headwater catchments. In large river basins such as Nile River Basin, there are needs to study, understand, and quantify the impacts of these modifications on the hydrologic

Tarek Mohamed Abdel-Aziz

2009-01-01

336

BENTHIC INVERTEBRATE BIOASSAYS WITH TOXIC SEDIMENT AND PORE WATER  

EPA Science Inventory

The relative sensitivities of bioassays to determine the toxicity of sediments were investigated and three methods of making the sample dilutions required to generate dose-response relationships were compared. he assays studied were: (a) Microtox, a 15-min assay of Photobacterium...

337

ATRAZINE DESORPTION KINETICS FROM A FRESH-WATER SEDIMENT  

EPA Science Inventory

Research has shown that the sorption and desorption of neutral organic compounds to soils and sediments occurs in two stages, with an initial rapid sorption/desorption phase (usually less than an hour) followed by a slower phase that can last for several months to years for very ...

338

Laboratory measurements of physical, chemical, and optical characteristics of Lake Chicot sediment waters  

NASA Technical Reports Server (NTRS)

Reflectance, chromaticity, diffuse attenuation, beam attenuation, and several other physical and chemical properties were measured for various water mixtures of lake bottom sediment. Mixture concentrations range from 5 ppm to 700 ppm by weight of total suspended solids in filtered deionized tap water. Upwelled reflectance is a nonlinear function of remote sensing wave lengths. Near-infrared wavelengths are useful for monitoring highly turbid waters with sediment concentrations above 100 ppm. It is found that both visible and near infrared wavelengths, beam attenuation correlates well with total suspended solids ranging over two orders of magnitude.

Witte, W. G.; Whitlock, C. H.; Usry, J. W.; Morris, W. D.; Gurganus, E. A.

1981-01-01

339

Analysis of national water pollution control policies: 2. Agricultural sediment control  

NASA Astrophysics Data System (ADS)

Application of a national water network model permits an analysis of the likely affects of agricultural sediment control policies on the quality of the nation's waters. This analysis is believed superior to previous assessments based mainly on erosion estimates without accounting for the characteristics of the receiving water or the contribution of pollutants from nonagricultural activities. Specifically, while the earlier assessments concluded that agriculture-related pollution problems are widespread and ubiquitous, this analysis concludes that it is probably more efficient to focus sediment-related pollution control policies on about one third of the nation's agricultural regions.

Gianessi, Leonard P.; Peskin, Henry M.

1981-08-01

340

Evaluation of hexavalent chromium in sediment pore water of the Hackensack River, New Jersey, USA.  

PubMed

Pore water was collected from in situ passive samplers in Hackensack River sediments adjacent to a chromite ore processing residue site in Kearny, New Jersey. Although the sediments at this site contained more than 3,000 mg/kg of total chromium (Cr) and shallow groundwater adjacent to the shore contained more than 1,000 microg/L of hexavalent Cr [Cr(VI)], concentrations of dissolved total Cr and Cr(VI) in pore water (PW) samples were less than ambient water quality criteria for Cr(VI) (50 microg/L). Concentrations of dissolved total Cr in pore water ranged from <2.0 to 5.3 microg/L, while Cr(VI) was not detected (<10 microg/L). These findings are consistent with previous studies, which demonstrated limited bioavailability and toxicity of Cr in sediment at this site and others with similar conditions. PMID:20821486

Driscoll, Susan Kane; McArdle, Margaret E; Plumlee, Megan H; Proctor, Deborah

2010-03-01

341

Normalized rare earth elements in water, sediments, and wine: identifying sources and environmental redox conditions  

USGS Publications Warehouse

The concentrations of the rare earth elements (REE) in surface waters and sediments, when normalized on an element-by-element basis to one of several rock standards and plotted versus atomic number, yield curves that reveal their partitioning between different sediment fractions and the sources of those fractions, for example, between terrestrial-derived lithogenous debris and seawater-derived biogenous detritus and hydrogenous metal oxides. The REE of ancient sediments support their partitioning into these same fractions and further contribute to the identification of the redox geochemistry of the sea water in which the sediments accumulated. The normalized curves of the REE that have been examined in several South American wine varietals can be interpreted to reflect the lithology of the bedrock on which the vines may have been grown, suggesting limited fractionation during soil development.

Piper, David Z.; Bau, Michael

2013-01-01

342

Sedimentation on the cold-water coral Lophelia pertusa: cleaning efficiency from natural sediments and drill cuttings.  

PubMed

Anthropogenic threats to cold-water coral reefs are trawling and hydrocarbon drilling, with both activities causing increased levels of suspended particles. The efficiency of Lophelia pertusa in rejecting local sediments and drill cuttings from the coral surface was evaluated and found not to differ between sediment types. Further results showed that the coral efficiently removed deposited material even after repeated exposures, indicating an efficient cleaning mechanism. In an experiment focusing on burial, fine-fraction drill cuttings were deposited on corals over time. Drill cutting covered coral area increased with repeated depositions, with accumulation mainly occurring on and adjacent to regions of the coral skeleton lacking tissue cover. Tissue was smothered and polyp mortality occurred where polyps became wholly covered by material. Burial of coral by drill cuttings to the current threshold level used in environmental risk assessment models by the offshore industry (6.3mm) may result in damage to L. pertusa colonies. PMID:21529851

Larsson, Ann I; Purser, Autun

2011-06-01

343

TOXICITY OF CADMIUM IN WATER AND SEDIMENT SLURRIES TO 'DAPHNIA MAGNA'  

EPA Science Inventory

Daphnia magna Straus were exposed to cadmium for 48 h in water and in equilibrated water sediment slurries using breakers and recirculating test chambers. Differences in toxicity based on dissolved and free cadmium (Cd(2+)) between the two levels of tested total solids 100 and 10...

344

Water and Sediment Quality in the Yukon River and its Tributaries Between Atlin, British  

E-print Network

........................................................................................................................................... 7 A Brief History of Hydrometric Monitoring Stations in the Yukon River Basin ................ 7 A Brief History of Environment Canada's Water-Quality Monitoring Program in the Yukon River BasinWater and Sediment Quality in the Yukon River and its Tributaries Between Atlin, British Columbia

345

ANALYSIS OF NATIONAL WATER POLLUTION CONTROL POLICIES. 2. AGRICULTURAL SEDIMENT CONTROL  

EPA Science Inventory

Application of a national water network model permits an analysis of the likely effects of agricultural sediment control policies on the quality of the nation's waters. This analysis is believed superior to previous assessments based mainly on erosion estimates without accounting...

346

Methyl parathion toxicity to and removal efficiency by Typha latifolia in water and artificial sediments  

Microsoft Academic Search

Methyl parathion (MeP) is a very hazardous pesticide freely used in agriculture in Mexico. This pesticide and others, arriving through different processes, exert significant effects on water quality with serious consequences for environmental and human health. This study evaluates the removal efficiency of common cattail Typha latifolia L. on MeP in water and artificial sediments. The effects of the pesticide

A. Amaya-Chávez; L. Martínez-Tabche; E. López-López; M. Galar-Martínez

2006-01-01

347

Use of compost filter bermsfor sediment trapping: primary focus on water quality and structural stability  

E-print Network

and composted bio-solids mixed with wood chips in a ratio of 50:50 on the runoff water quality, as well as, the sediment removal efficiencies. Field tests were performed on the berms to simulate conventional rainfall runoff and the tested water was collected...

Raut Desai, Aditya Babu

2004-11-15

348

Land conversion to bioenergy production: water budget and sediment output in a semiarid grassland  

Technology Transfer Automated Retrieval System (TEKTRAN)

Switchgrass based bioenergy production has been considered a feasible alternative of land use for the mixed-grass prairie and marginal croplands in the High Plains. However, little is known of the effect of this land use change on the water cycle and associated sediment output in this water controll...

349

DEVELOPMENT AND DEMONSTRATION OF A BIDIRECTIONAL ADVECTIVE FLUX METER FOR SEDIMENT-WATER INTERFACE  

EPA Science Inventory

A bidirectional advective flux meter for measuring water transport across the sediment-water interface has been successfully developed and field tested. The flow sensor employs a heat-pulse technique combined with a flow collection funnel for the flow measurement. Because the dir...

350

COSOLVENT EFFECTS ON PHENANTHRENE SORPTION-DESORPTION ON A FRESH-WATER SEDIMENT  

EPA Science Inventory

This study evaluated the effects of the water-miscible cosolvent methanol on the sorption-desorption of phenanthrene by the natural organic matter (NOM) of a fresh-water sediment. A biphasic pattern was observed in the relationship between the log of the carbon-normalized sorpti...

351

NITROGEN DYNAMICS IN SEDIMENT DURING WATER LEVEL MANIPULATION ON THE UPPER MISSISSIPPI RIVER  

Microsoft Academic Search

Nitrogen (N) has been linked to increasing eutrophication in the Gulf of Mexico and as a result there is increased interest in managing and improving water quality in the Mississippi River system. Water level reductions, or 'drawdowns', are being used more frequently in large river impoundments to improve vegetation growth and sediment compaction. We selected two areas of the Upper

JENNIFER C. CAVANAUGH; WILLIAM B. RICHARDSON; ERIC A. STRAUSSb; LYNN A. BARTSCHa

352

An environmental fate study of methoxychlor using water-sediment model system.  

PubMed

Agricultural waste water containing pesticides can reach the sea via rivers and estuaries, including brackish lakes. We studied the metabolic fate of methoxychlor [MXC; 1,1,1-trichloro-2,2-bis(4-methoxyphenyl)ethane] in a model system consisting of sediment and associated water collected from two sampling sites: a brackish lake and a freshwater river. MXC degraded rapidly and was finally mineralized in both sediment systems. The first step of degradation was dechlorination to yield 1,1-dichloro-2,2-bis(4-methoxyphenyl)ethane [de-Cl-MXC] or CN-replacement to yield 2,2-bis(4-methoxyphenyl)acetonitrile [MXC-CN], followed by O-demethylation. Although the metabolites were common to the two sediments, the dynamics of the metabolites over time were clearly distinct. In the brackish lake sediment, de-Cl-MXC accumulated transiently, whereas in the river sediment, it was rapidly converted to its demethylated metabolite. We also found that dechlorination and CN-replacement proceeded in autoclave-sterilized river sediment. In the river sediment, the abiotic reaction mediated by abundant humic acid and low oxygen level also appeared to contribute to the overall MXC metabolism. PMID:22232250

Masuda, Minoru; Satsuma, Koji; Sato, Kiyoshi

2012-01-01

353

Magnetic field-enhanced sedimentation of nanopowder magnetite in water flow.  

PubMed

Sedimentation dynamics of magnetite (?-Fe3O4) nanopowder (10-20?nm) in water in a gradient magnetic field Bmax?=?0.3 T, (dB/dz)max?=?0.13?T/cm was studied for different water flow speeds and starting particle concentrations (0.1 and 1.0?g/l). The aggregates formation in water was monitored under the same conditions. In cyclical water flow, the velocity of particle sedimentation increases significantly in comparison to its rate in still water, which corresponds to the intensified aggregate formation. However, at a water flow speed more than 0.1?cm/s sedimentation velocity slows down, which might be connected to aggregate destruction in a faster water flow. Correlation between sedimentation time and the nanoparticle concentration in water does not follow the trend expected for spherical superparamagnetic particles. In our case sedimentation time is shorter for c?=?0.1?g/l in comparison with that for c?=?1?g/l. We submit that such a feature is caused by particle self-organization in water into complex structures of fractal type. This effect is unexplained in the framework of existing theoretical models of colloids systems, so far. Provisional recommendations are suggested for the design of a magnetic separator on the permanent magnets base. The main device parameters are magnetic field intensity B???0.1?T, magnetic field gradient (dB/dz)max ? (0.1-0.2)?T/cm, and water flow speed V?water from magnetite down to ecological and hygienic standards is reached in 80?min, for c?=?0.1 g/l the time is reduced down to 50?min. PMID:25650300

Bakhteeva, Iu; Medvedeva, I; Byzov, I; Zhakov, S; Yermakov, A; Uimin, M; Shchegoleva, N

2015-07-01

354

A new device for collection of interstitial water from wetland sediments  

USGS Publications Warehouse

A sampler for collection of interstitial water from wetland sediments is described. It differs from other sampling devices because it does not have to be filled with solution to facilitate diffusion, it does not have to be removed from the wetland to collect samples, and it can be used to draw repeated samples over time from identical locations. The device facilitates 'in situ' measurement of a wide range of abiotic parameters such as electrical conductivity, redox potential, and pH in wetland sediments. The device has application in ecological investigations of sediment-borne wildlife diseases, studies of benthic invertebrates, measurement of nutrient exchange, and other aspects of wetland ecology.

Euliss, N.H., Jr.; Barnes, R.K.

1992-01-01

355

Phase distribution of PAH (polycyclic aromatic hydrocarbons) in Great Lakes waters and sediments  

SciTech Connect

Freshly collected Great Lakes waters were innoculated with radiolabelled polycyclic aromatic hydrocarbons (PAH) and, after equilibration, separated into particle bound, dissolved organic matter bound and freely dissolved phases. Solubility controls the constituent distribution between particle bound and freely dissolved but plays a much smaller role in mediating the binding to dissolved organic matter. The results of these experiments yield the same equilibrium particle distribution coefficients (Kd) as those using freshly collected sediment trap material as the substrate. The results for field measurement of sediment Kds in a core from Lake Erie and surface sediments from several lakes are generally significantly lower.

Eadie, B.J.; Faust, W.; Morehead, N.; Robbins, J. (Great Lakes Environmental Research Laboratory, Ann Arbor, MI (USA))

1990-01-01

356

A comparison of solids collected in sediment traps and automated water samplers  

USGS Publications Warehouse

Sediment traps are being used in some pollution monitoring programs in the USA to sample suspended solids for contaminant analyses. This monitoring approach assumes that the characteristics of solids obtained in sediment traps are the same as those collected in whole-water sampling devices. We tested this assumption in the upper Mississippi River, based on the inorganic particle-size distribution (determined with a laser particle- analyzer) and volatile matter content of solids (a surrogate for organic matter). Cylindrical sediment traps (aspect ratio 3) were attached to a rigid mooring device and deployed in a flowing side channel in Navigation Pool 7 of the upper Mississippi River. On each side of the mooring device, a trap was situated adjacent to a port of an autosampler that collected raw water samples hourly to form 2-d composite samples. Paired samples (one trap and one raw water, composite sample) were removed from each end of the mooring device at 2-d intervals during the 30-d study period and compared. The relative particle collection efficiency of paired samplers did not vary temporally. Particle-size distributions of inorganic solids from sediment traps and water samples were not significantly different. The volatile matter content of solids was lesser in sediment traps (mean, 9.5%) than in corresponding water samples (mean, 22.7%). This bias may have been partly due to under-collection of phytoplankton (mainly cyanobacteria), which were abundant in the water column during the study. The positioning of water samplers and sediment traps in the mooring device did not influence the particle-size distribution or total solids of samples. We observed a small difference in the amount of organic matter collected by water samplers situated at opposite ends of the mooring device.

Bartsch, L.A.; Rada, R.G.; Sullivan, J.F.

1996-01-01

357

An algorithm for the retrieval of suspended sediment in coastal waters of China from AVHRR data  

NASA Astrophysics Data System (ADS)

An algorithm using an analytical model based on the difference of the NOAA/AVHRR (Advanced Very High Resolution Radiometer) Channel 1 (580-680 nm) and Channel 2 (720-1100 nm) reflectance data is developed for the retrieval of suspended sediment in coastal and shelf waters. The model assumes that the suspended sediment concentration, S, is a function of the difference of the water leaving reflectance of Channels 1 and 2, Rd. The formula is governed by the optical parameters of water and suspended sediment, including volume scattering and absorption coefficients of the two channels. The analytical model yielded a best fit curve when the water leaving reflectance of the two channels were plotted against each other for Case 2 water, where the suspended sediment concentration ranged from 5 to over 100 g m -3. A standard curve of S against Rd was obtained. Using Tassan (1994)'s recommendations for the contribution of water and suspended sediment to the in-water absorption and backscattering coefficients in his three-component color model, the suspended sediment concentration corresponding to the maximum point of Rd was about 60 g m -3, and was independent of the atmospheric optical properties. Thus, this process provides a convenient tool to remove the atmospheric fluctuations of atmospheric transmittance by reconciling the maximum point of the image with the standard curve. The algorithm was tested using data from seven transects in the China Sea, and the retrieved results for the Zhujiang (Pearl River) Estuary were compared with the sea-truth data with good agreement. This suggests that the algorithm can be used as a seasonal regional model for water masses along the China coast.

Li, Yan; Huang, Wei; Fang, Ming

1998-04-01

358

The Association of Cryptosporidium parvum With Suspended Sediments: Implications for Transport in Surface Waters  

NASA Astrophysics Data System (ADS)

Understanding the transport and fate of microorganisms in surface waters is of vital concern in protecting the integrity and safety of municipal water supply systems. The human pathogen Cryptosporidium parvum is a particular public health interest, as it is ubiquitous in the surface waters of the United States, it can persist for long periods in the environment, and it is difficult to disinfect in water treatment plants. Due to its small size (5 um), low specific gravity (1.05 g/cm3), and negative surface charge, C. parvum oocysts are generally considered to move through watersheds from their source to drinking water reservoirs with little attenuation. However, the transport of the oocysts in surface waters may be mediated by interactions with suspended sediments. Batch experiments were conducted to determine the extent of C. parvum oocyst attachment to several inorganic and organic sediments under varying water chemical conditions, and settling column experiments were performed to demonstrate how these associations influence the effective settling velocity of C. parvum oocysts. Results from these experiments showed that C. parvum oocysts do associate with inorganic and organic sediments and often settle at the rate of the suspended sediment. The size and surface charge of the host suspended sediment influenced the extent of oocyst attachment as oocysts preferentially associated with particles greater than 3 um, and fewer oocysts associated with particles having a highly negative surface charge. Background water chemical conditions including ionic strength, ion composition, and pH did not have a significant effect on oocyst attachment to suspended sediments.

Searcy, K. E.; Packman, A. I.; Atwill, E. R.; Harter, T.

2003-12-01

359

Natural and artificial radionuclides in the Suez Canal bottom sediments and stream water  

Microsoft Academic Search

Concentration of natural and artificial radionuclides in Suez Canal bottom sediments and stream water have been measured using gamma spectrometers based on a hyper-pure Ge detector. The activity concentrations of 238U series, 232Th series and 40K did not exceed 16.0, 15.5 and 500.0 Bq kg-1 dry weight for sediments. The activity concentration of 238U series and 40K did not exceed

M. S. El-Tahawy; M. A. Farouk; N. M. Ibrahiem; S. A. M. El-Mongey

1994-01-01

360

Seasonal and spatial patterns in mass and organic matter sedimentation in the North Water  

Microsoft Academic Search

Sedimentation rates in the North Water between September 1997 and July 1999 were calculated from integrated monthly values for dry and organic matter, organic carbon, nitrogen, and sum-chloropigments, using pairs of multi-cup sediment traps moored at two depths >200m at five stations. Highest fluxes in upper traps (144 and 297gm?2yr?1, 8 and 12gCm?2yr?1) occurred near Ellesmere Island at the western

B. T Hargrave; I. D Walsh; D. W Murray

2002-01-01

361

Rare earth elements in the pore waters of reducing nearshore sediments  

Microsoft Academic Search

The REE are mobile during early diagenesis in reducing nearshore sediments of Buzzards Bay leading to greatly enhanced concentrations in pore waters, e.g. 815 pmol kg-1 Nd and 1910 pmol kg-1 Ce within 30 cm of the sediment-seawater interface, about 10-50 times local seawater values. Two principal diagenetic reactions have been identified. Preferential Ce enrichment (positive Ce anomalies) and preferential

H. Elderfield; E. R. Sholkovitz

1987-01-01

362

Arctic sediments (Svalbard): pore water and solid phase distributions of C, N, P and Si  

Microsoft Academic Search

Pore water and solid phase distributions of C, N, P and Si in sediments of the Arctic Ocean (Svalbard area) have been investigated.\\u000a Concentrations of organic carbon (Corg) in the solid phase of the sediment varied from 1.3 to 2.8% (mean 1.9%), with highest concentrations found at shallow stations\\u000a south\\/southwest of Svalbard. Relatively low concentrations were obtained at the deeper

S. Hulth; P. O. J. Hall; A. Landén; T. H. Blackburn

1996-01-01

363

Occurrence of macrophyte monocultures in drainage ditches relates to phosphorus in both sediment and water.  

PubMed

Monocultures of functional equivalent species often negatively affect nutrient cycling and overall biodiversity of aquatic ecosystems. The importance of water and sediment nutrients for the occurrence of monocultures was analysed using field data from drainage ditches. Ranges of nutrients were identified that best explained the occurrence of monocultures of Elodea nuttallii (Planch.) St. John (Waterweed type), monocultures of duckweed (Duckweed type) and the occurrence of a diverse submerged vegetation (Mixed type). Results indicated these three vegetation types occurred at distinctive ranges of phosphorus in water and sediment. Sediment phosphorus distinguished monocultures from the Mixed type, with the two monocultures occurring at two to four times higher concentrations. The Waterweed type occurred at higher sediment phosphorus levels than the mixed type, showed a higher degree of dominance and lower number of red list species. Phosphorus concentrations in water were four to six times higher in the Duckweed type compared to the Waterweed and Mixed type. The three vegetation types had comparable total biomass which was unexpected. This comparability was likely caused by duckweed only growing at the water surface at the highest nutrient levels and the limited space in drainage ditches for increased submerged biomass development at high nutrient availability. Possible measures to limit the occurrence of monocultures, and thereby increasing the ecological quality, are discussed with focus on lowering phosphorus concentrations in both water and sediment and on removal of plant species that develop into monocultures. PMID:24255858

van Zuidam, Jeroen P; Peeters, Edwin Thm

2013-01-01

364

Determination of organochlorine pesticide residue in sediment and water from the Densu river basin, Ghana.  

PubMed

The distribution of organochlorine pesticides in the aquatic ecosystem from the Densu river revealed varying levels of concentration in water and the sediment samples. Three locations were sampled along the river to evaluate the levels of organochlorine pesticide residue in the river. Sediment and surface water samples were extracted by soxhlet and liquid-liquid extraction respectively and analyzed using Gas Chromatograph coupled with electron capture detector. The detectable organochlorine pesticides were gamma-hexachlorocyclohexane (HCH), delta-hexachlorocyclohexane, heptachlor, aldrin and dieldrin. The other pesticides that were investigated are gamma-chlordane, alpha endosulfan, endosulfan sulfate, p,p'-DDT and its metabolite p,p'-DDE, methoxychlor, endrin and its metabolite endrin aldehyde and endrin ketone. The order of increasing frequency of detection of samples was higher in sediment than water. In sediment, the mean concentration ranged from 0.030 ?g kg(-1) dry weight (endrin) to 10.98 ?g kg(-1) dry weight (aldrin). The highest detected concentration of organochlorine in water was endosulfan sulfate with mean concentration of 0.185 ?g L(-1). Analysis of variance indicated significant differences for most organochlorine pesticide residue in the sediment sampled from the various locations. Some of the levels of organochlorine pesticides detected in water were relatively high compared to guideline values set by World Health Organization and Australia and thus could be harmful if the trend is not checked. PMID:22123529

Kuranchie-Mensah, Harriet; Atiemo, Sampson Manukure; Palm, Linda Maud Naa-Dedei; Blankson-Arthur, Sarah; Tutu, Anita Osei; Fosu, Paul

2012-01-01

365

An Integrated Assessment of Sediment Remediation in a Midwestern U.S. Stream Using Sediment Chemistry, Water Quality, Bioassessment and Fish Biomarkers  

EPA Science Inventory

A comprehensive biological, sediment and water quality study of the lower Little Scioto River near Marion, Ohio, USA was undertaken in July 2007 to evaluate the effectiveness of removal of creosote-contaminated sediment. The study area covered 7.5 river miles (RMs) of the river, ...

366

Summary of Suspended-Sediment Concentration Data, San Francisco Bay, California, Water Year 2006  

USGS Publications Warehouse

Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water-year 2006 (October 1, 2005-September 30, 2006). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, one site in San Pablo Bay, two sites in Central San Francisco Bay, and one site in South San Francisco Bay. Sensors were positioned at two depths at most sites to help define the vertical variability of suspended sediments. Water samples were collected periodically and analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the output of the optical sensors so that a record of suspended-sediment concentrations could be derived. This report presents the data-collection methods used and summarizes, in graphs, the suspended-sediment concentration data collected from October 2005 through September 2006. Calibration curves and plots of the processed data for each sensor also are presented.

Buchanan, Paul A.; Lionberger, Megan A.

2009-01-01

367

Solar heating, cooling, and domestic hot water system installed at Kaw Valley State Bank and Trust Company, Topeka, Kansas  

NASA Technical Reports Server (NTRS)

The building has approximately 5600 square feet of conditioned space. Solar energy was used for space heating, space cooling, and preheating domestic hot water (DHW). The solar energy system had an array of evacuated tube-type collectors with an area of 1068 square feet. A 50/50 solution of ethylene glycol and water was the transfer medium that delivered solar energy to a tube-in-shell heat exchanger that in turn delivered solar heated water to a 1100 gallon pressurized hot water storage tank. When solar energy was insufficient to satisfy the space heating and/or cooling demand, a natural gas-fired boiler provided auxiliary energy to the fan coil loops and/or the absorption chillers. Extracts from the site files, specification references, drawings, and installation, operation and maintenance instructions are presented.

1980-01-01

368

Solar heating, cooling, and domestic hot water system installed at Kaw Valley State Bank and Trust Company, Topeka, Kansas  

NASA Astrophysics Data System (ADS)

The building has approximately 5600 square feet of conditioned space. Solar energy was used for space heating, space cooling, and preheating domestic hot water (DHW). The solar energy system had an array of evacuated tube-type collectors with an area of 1068 square feet. A 50/50 solution of ethylene glycol and water was the transfer medium that delivered solar energy to a tube-in-shell heat exchanger that in turn delivered solar heated water to a 1100 gallon pressurized hot water storage tank. When solar energy was insufficient to satisfy the space heating and/or cooling demand, a natural gas-fired boiler provided auxiliary energy to the fan coil loops and/or the absorption chillers. Extracts from the site files, specification references, drawings, and installation, operation and maintenance instructions are presented.

1980-11-01

369

Factors controlling the silicon isotope distribution in waters and surface sediments of the Peruvian coastal upwelling  

NASA Astrophysics Data System (ADS)

We present the first systematic study of the silicon isotope composition in the water column (?30Si) and in diatoms (?30Sidiatom) from the underlying surface sediments in a coastal upwelling region. The surface waters upwelling on the shelf off Peru are mainly fed by southward flowing subsurface waters along the coast, which show a mean ?30Si of +1.5‰. The concentration of dissolved silicic acid (Si(OH)4) increases towards the south in these waters and with increasing water depth, suggesting lateral mixing with water masses from the south and intense remineralisation of particulate biogenic silica (bSiO2) in the water column and in the surface sediments. Surface waters in the realm of the most intense upwelling between 5°S and 15°S have only marginally elevated ?30Si values (?30Si = +1.7‰) with respect to the source Si isotope composition, whereas further north and south, where upwelling is less pronounced, surface waters are more strongly fractionated (?30Si up to +2.8‰) due to the stronger utilisation of the smaller amounts of available Si(OH)4. The degree of Si(OH)4 utilisation in the surface waters along the shelf estimated from the Si(OH)4 concentration data ranges from 51% to 93%. The ?30Sidiatom values of hand-picked diatoms in the underlying surface sediments vary from +0.6‰ to +2.0‰, which is within the range of the expected fractionation between surface waters and diatoms. The fractionation signal in the surface waters produced during formation of the diatoms is reflected by the ?30Sidiatom values in the underlying sediments, with the lowest ?30Sidiatom values in the main upwelling region. The silicon isotope compositions of bSiO2 (?30Si) from the same surface sediment samples are generally much lower than the ?30Sidiatom signatures indicating a significant contamination of the bSiO2 with biogenic siliceous material other than diatoms, such as sponge spicules. This shift towards lighter ?30Si values by up to -1.3‰ compared to ?30Sidiatom signatures for the same surface sediment samples potentially biases the interpretation of ?30Si paleorecords from sediments with low bSiO2 concentrations, and thus the reconstruction of past Si(OH)4 utilisation in surface waters.

Ehlert, Claudia; Grasse, Patricia; Mollier-Vogel, Elfi; Böschen, Tebke; Franz, Jasmin; de Souza, Gregory F.; Reynolds, Ben C.; Stramma, Lothar; Frank, Martin

2012-12-01

370

Historical Influence of Soil and Water Management on Sediment and Carbon Erosion and Burial in the United States  

Microsoft Academic Search

The documented history of U.S. soil and water management provides a unique opportunity to examine soil and sediment carbon storage under conditions of changing management practices. Historical acceleration of erosion due to cultivation has been moderated by improved soil management. Increased construction of dams and locks has expanded areas of aquatic sedimentation in reservoirs and ponds. Enhanced historical sediment deposition

E. T. Sundquist; K. V. Ackerman; R. F. Stallard; N. B. Bliss; S. Liu

2006-01-01

371

Suspended-sediment and fresh-water discharges in the Ob and Yenisey rivers, 1960-1988  

Microsoft Academic Search

Of the world's great rivers, the Ob and Yenisey rank among the largest suppliers of fresh water and among the smallest suppliers of suspended sediment to the coastal ocean. Sediment in the middle reaches of the rivers is mobilized from bordering terraces and exchanged between channels and flood plains. Sediment in the lower reaches of these great rivers is deposited

R. H. Meade; N. N. Bobrovitskaya; V. I. Babkin

2000-01-01

372

Journal of Hydrology 164 (1995) 109-125 Fluxes of water and solute in a coastal wetland sediment.  

E-print Network

be explained if recharge to the sediment occurred by downward infiltration in macropores and discharge occurred and solute in a coastal wetland sediment. 2. Effect of macropores on solute exchange with surface water December 1993;revision accepted 22 June 1994 Abstract We investigated interactions between sediment

373

Sediment, nutrient and water losses by water erosion under agroforestry systems in the semi-arid region in northeastern Brazil  

Microsoft Academic Search

Inadequate soil management practices adopted in the Brazilian semi-arid region contribute to erosive processes. Agroforestry\\u000a systems (AFs) have been considered an alternative to reduce water erosion. This study aimed to evaluate the impact of two\\u000a alternatives AFs, a traditional and an intensive cropping system on the losses of sediments, water, organic carbon and nutrients\\u000a caused by water erosion in comparison

Maria Ivanilda de Aguiar; Stoécio Malta Ferreira Maia; Francisco Alisson da Silva Xavier; Eduardo de Sá Mendonça; João Ambrósio Araújo Filho; Teógenes Senna de Oliveira

2010-01-01

374

Methods for determination of inorganic substances in water and fluvial sediments  

USGS Publications Warehouse

Chapter Al of the laboratory manual contains methods used by the U.S. Geological Survey to analyze samples of water, suspended sediments, and bottom material for their content of inorganic constituents. Included are methods for determining the concentration of dissolved constituents in water, the total recoverable and total of constituents in water-suspended sediment samples, and the recoverable and total concentrations of constituents in samples of bottom material. The introduction to the manual includes essential definitions and a brief discussion of the use of significant figures in calculating and reporting analytical results. Quality control in the water-analysis laboratory is discussed, including the accuracy and precision of analyses, the use of standard-reference water samples, and the operation of an effective quality-assurance program. Methods for sample preparation and pretreatment are given also. A brief discussion of the principles of the analytical techniques involved and their particular application to water and sediment analysis is presented. The analytical methods of these techniques are arranged alphabetically by constituent. For each method, the general topics covered are the application, the principle of the method, the interferences, the apparatus and reagents required, a detailed description of the analytical procedure, reporting results, units and significant figures, and analytical precision data, when available. More than 126 methods are given for the determination of 70 inorganic constituents and physical properties of water, suspended sediment, and bottom material.

Fishman, Marvin J., (Edited By); Friedman, Linda C.

1989-01-01

375

Sediment desiccation as a driver of phosphate availability in the water column of Mediterranean wetlands.  

PubMed

Sediment desiccation is expected to drastically affect nutrient cycling in Mediterranean wetlands as global climate change models predict that many areas will become significantly drier than they currently are. In this study, we selected two Mediterranean wetlands that clearly differ in their water chemical composition (Honda and Hituelo wetlands) in order to determine the impact of sediment desiccation on phosphate (PO?(3-)) adsorption and desorption properties. A decrease in PO?(3-) sorption properties was observed in transects from the littoral zone to dry land in both lakes concomitantly with a reduction in organic matter content, revealing a critical role of organic matter for sequestering P in the lake sediment. Our experiments designed to determine if drying events would lead to an enhanced P release upon re-wetting have shown that, simulating natural conditions of re-flooding (that is without adding sodium azide), PO?(3-) concentrations were notably higher in the overlying water than those initially measured in the lake water. These results highlight the impact of drying sediment and the subsequent re-wetting on increasing P concentrations in lake water and accordingly, affecting to lake trophic state. Finally, we aimed on determining the overall effect of biotic versus abiotic activity on P release patterns observed upon re-wetting. Our results have evidenced that while in Honda, biotic processes upon re-wetting are crucial for increasing P retention in the sediment; P exchange across sediment and water upon dry sediment re-wetting is basically mediated by abiotic processes in Hituelo. PMID:23988744

Gilbert, Juan Diego; Guerrero, Francisco; de Vicente, Inmaculada

2014-01-01

376

Diffusive release of uranium from contaminated sediments into capillary fringe pore water  

SciTech Connect

Despite remediation efforts at the former nuclear weapons facility at the Hanford site (Washington State), leaching of uranium (U) from contaminated sediments to the ground water persists at the Hanford 300 Area. Flooding of contaminated capillary fringe sediments due to seasonal changes in the Columbia River stage has been identified as a reason of continued U supply to ground water. We investigated the release of U from Hanford capillary fringe sediments to pore water. Contaminated Hanford sediments were packed into reservoirs of centrifugal filter devices and saturated with Columbia River water for 3 to 84 days at varying solution-to-solid ratios (1:3, 1:1, 5:1, 10:1, 25:1 mL:g). After specified times, samples were centrifuged to a gravimetric water content of 0.11 ± 0.06 g g-1. Within the first three days, there was an initial rapid release of 6-9% of total U from the sediments into the pore water, independent of the solution-to-solid ratio. After 14 days of reaction, however, the experiments with the narrowest solution-to-solid ratios (1:3 and 1:1 mL:g) showed a decline in dissolved U concentrations. The removal of U from the solution phase was accompanied by removal of Ca and HCO3-. Geochemist workbench simulations, conducted using measured solution concentrations from experiments, indicated that calcite could precipitate in the 1:3 solution-to-solid ratio experiment. After the rapid initial release in the first three days for the 5:1, 10:1, and 25:1 solution-to-solid ratio experiments, there was sustained release of U into the pore water. Up to 22% of total U was released on day 84 for the 25:1 solution-to-solid ratio reaction. This sustained release of U from the sediments had diffusion-limited kinetics.

Rod, Kenton A.; Wellman, Dawn M.; Flury, Markus; Pierce, Eric M.; Harsh, James B.

2012-10-01

377

[Indication of Northern Caspian regions by biochemical (enzymatic) indices of water and bottom sediments].  

PubMed

We evaluated ecological status in the region of mixing of river and sea waters in the northern Caspian Sea with high anthropogenic pressure. We studied the regions of Volga River fore-delta, the water areas neighboring ancient hydrological transects, and the sea regions between the transects. The water areas were evaluated by biochemical degradation of organic compounds (proteinase and amylase activities) in water and bottom sediments as well as hydrochemical indices of water (salt composition and contents of dissolved oxygen and biogenic compounds). In conditions of active vegetation of phytoplankton and higher aquatic plants soon after the highest wave of the Volga flood, we studied distribution of hydrolytic enzyme activities involved in the global production/destruction cycle of high molecular weight organic compounds (proteins and polysaccharides). The data obtained with the trypsin-azocasein and alpha-amylase-modified starch tests indicates pollution of water and surface sediments in the lower reaches of Volga and the inflow sea regions. PMID:14735793

Korneeva, G A; Miroshnik, L Iu; Tsytsarin, A G

2003-01-01

378

Water volume and sediment accumulation in Lake Linganore, Frederick County, Maryland, 2009  

USGS Publications Warehouse

To assist in understanding sediment and phosphorus loadings and the management of water resources, a bathymetric survey was conducted at Lake Linganore in Frederick County, Maryland in June 2009 by the U.S. Geological Survey, in cooperation with the City of Frederick and Frederick County, Maryland. Position data and water-depth data were collected using a survey grade echo sounder and a differentially corrected global positioning system. Data were compiled and edited using geographic information system software. A three-dimensional triangulated irregular network model of the lake bottom was created to calculate the volume of stored water in the reservoir. Large-scale topographic maps of the valley prior to inundation in 1972 were provided by the City of Frederick and digitized. The two surfaces were compared and a sediment volume was calculated. Cartographic representations of both water depth and sediment accumulation were produced along with an area/capacity table. An accuracy assessment was completed on the resulting bathymetric model. Vertical accuracy at the 95-percent confidence level for the collected data, the bathymetric surface model, and the bathymetric contour map was calculated to be 0.95 feet, 1.53 feet, and 3.63 feet, respectively. The water storage volume of Lake Linganore was calculated to be 1,860 acre-feet at full pool elevation. Water volume in the reservoir has decreased by 350 acre-feet (about 16 percent) in the 37 years since the dam was constructed. The total calculated volume of sediment deposited in the lake since 1972 is 313 acre-feet. This represents an average rate of sediment accumulation of 8.5 acre-feet per year since Linganore Creek was impounded. A sectional analysis of sediment distribution indicates that the most upstream third of Lake Linganore contains the largest volume of sediment whereas the section closest to the dam contains the largest amount of water. In comparison to other Maryland Piedmont reservoirs, Lake Linganore was found to have one of the lowest sedimentation rates at 0.26 cubic yards per year per acre of drainage area. Sedimentation rates in other comparable Maryland reservoirs were Prettyboy Reservoir (filling at a rate of 2.26 cubic yards per year per acre), Loch Raven Reservoir (filling at a rate of 0.88 cubic yards per year per acre) and Piney Run Reservoir (filling at a negligible rate).

Sekellick, Andrew J.; Banks, S.L.

2010-01-01

379

Laboratory upwelled radiance and reflectance spectra of Kerr reservoir sediment waters  

NASA Technical Reports Server (NTRS)

Reflectance, chromaticity, and several other physical and chemical properties were measured for various water mixtures of bottom sediments taken from two sites at Kerr Reservoir, Virginia. Mixture concentrations ranged from 5 to 1000 ppm by weight of total suspended solids (TSS) in filtered deionized tap water. The two sets of radiance and reflectance spectra obtained were similar in shape and magnitude for comparable values of TSS. Upwelled reflectance was observed to be a nonlinear function of TSS with the degree of curvature a function of wavelength. Sediment from the downstream site contained a greater amount of particulate organic carbon than from the upstream site. No strong conclusions can be made regarding the effects of this difference on the radiance and reflectance spectra. Near-infrared wavelengths appear useful for measuring highly turbid water with concentrations up to 1000 ppm or more. Chromaticity characteristics do not appear useful for monitoring sediment loads above 150 ppm.

Witte, W. G.; Whitlock, C. H.; Morris, W. D.; Gurganus, E. A.

1982-01-01

380

Diffusive release of uranium from contaminated sediments into capillary fringe pore water.  

PubMed

Despite remediation efforts at the former nuclear weapons facility, leaching of uranium (U) from contaminated sediments to the ground water persists at the Hanford site 300 Area. Flooding of contaminated capillary fringe sediments due to seasonal changes in the Columbia River stage has been identified as a source for U supply to ground water. We investigated U release from Hanford capillary fringe sediments by packing sediments into reservoirs of centrifugal filter devices and saturating them with Columbia River water for 3 to 84days at varying solution-to-solid ratios. After specified times, samples were centrifuged. Within the first three days, there was an initial rapid release of 6-9% of total U, independent of the solution-to-solid ratio. After 14days of reaction, however, the experiments with the narrowest solution-to-solid ratios showed a decline in dissolved U concentrations. The removal of U from the solution phase was accompanied by removal of Ca and HCO(3)(-). Geochemical modeling indicated that calcite could precipitate in the narrowest solution-to-solid ratio experiment. After the rapid initial release in the first three days for the wide solution-to-solid ratio experiments, there was sustained release of U into the pore water. This sustained release of U from the sediments had diffusion-limited kinetics. PMID:23041367

Rod, Kenton A; Wellman, Dawn M; Flury, Markus; Pierce, Eric M; Harsh, James B

2012-10-01

381

Diffusive release of uranium from contaminated sediments into capillary fringe pore water  

NASA Astrophysics Data System (ADS)

Despite remediation efforts at the former nuclear weapons facility, leaching of uranium (U) from contaminated sediments to the ground water persists at the Hanford site 300 Area. Flooding of contaminated capillary fringe sediments due to seasonal changes in the Columbia River stage has been identified as a source for U supply to ground water. We investigated U release from Hanford capillary fringe sediments by packing sediments into reservoirs of centrifugal filter devices and saturating them with Columbia River water for 3 to 84 days at varying solution-to-solid ratios. After specified times, samples were centrifuged. Within the first three days, there was an initial rapid release of 6-9% of total U, independent of the solution-to-solid ratio. After 14 days of reaction, however, the experiments with the narrowest solution-to-solid ratios showed a decline in dissolved U concentrations. The removal of U from the solution phase was accompanied by removal of Ca and HCO3-. Geochemical modeling indicated that calcite could precipitate in the narrowest solution-to-solid ratio experiment. After the rapid initial release in the first three days for the wide solution-to-solid ratio experiments, there was sustained release of U into the pore water. This sustained release of U from the sediments had diffusion-limited kinetics.

Rod, Kenton A.; Wellman, Dawn M.; Flury, Markus; Pierce, Eric M.; Harsh, James B.

2012-10-01

382

Diffusive release of uranium from contaminated sediments into capillary fringe pore water  

SciTech Connect

Despite remediation efforts at the former nuclear weapons facility, leaching of uranium (U) from contaminated sediments to the ground water persists at the Hanford site 300 Area. Flooding of contaminated capillary fringe sediments due to seasonal changes in the Columbia River stage has been identified as a source for U supply to ground water. We investigated U release from Hanford capillary fringe sediments by packing sediments into reservoirs of centrifugal filter devices and saturated with Columbia River water for 3 to 84 days at varying solution-to-solid ratios. After specified times, samples were centrifuged. Within the first three days, there was an initial rapid release of 6-9% of total U, independent of the solution-to-solid ratio. After 14 days of reaction, however, the experiments with the narrowest solution-to-solid ratios showed a decline in dissolved U concentrations. The removal of U from the solution phase was accompanied by removal of Ca and HCO3-. Geochemical modeling indicated that calcite could precipitate in the narrowest solution-to-solid ratio experiment. After the rapid initial release in the first three days for the wide solution-to-solid ratio experiments, there was sustained release of U into the pore water. This sustained release of U from the sediments had diffusion-limited kinetics.

Rod, Kenton A. [Pacific Northwest National Laboratory (PNNL); Wellman, Dawn M. [Pacific Northwest National Laboratory (PNNL); Flury, Markus [Washington State University, Pullman; Pierce, Eric M [ORNL; Harsh, James B. [Washington State University, Pullman

2012-01-01

383

Release of elements to natural water from sediments of Lake Roosevelt, Washington, USA.  

PubMed

Reservoir sediments from Lake Roosevelt (WA, USA) that were contaminated with smelter waste discharged into the Columbia River (BC, Canada) were examined using three measures of elemental release reflecting varying degrees of physical mixing and time scales. Aqueous concentrations of Cd, Cu, Pb, and Zn in the interstitial water of reservoir sediments, in the gently stirred overlying waters of incubated sediment cores, and in supernatants of aggressively tumbled slurries of reservoir sediments generally were higher than the concentrations from a reference site. When compared to chronic water-quality criteria, all three measures of release suggest that slag-contaminated sediments near the U.S.-Canadian border are potentially toxic as a result of Cu release and Pb release in two of the three measures. All three measures of Cd release suggest potential toxicity for one site farther down the reservoir, probably contaminated as a result of transport and adsorption of Cd from smelter liquid waste. Releases of Zn and As did not appear to be potentially toxic. Carbonate geochemistry indirectly affects the potential toxicity by increasing water hardness. PMID:18020685

Paulson, Anthony J; Cox, Stephen E

2007-12-01

384

Identification of Water-Quality Trends Using Sediment Cores from Dillon Reservoir, Summit County, Colorado  

USGS Publications Warehouse

Since the construction of Dillon Reservoir, in Summit County, Colorado, in 1963, its drainage area has been the site of rapid urban development and the continued influence of historical mining. In an effort to assess changes in water quality within the drainage area, sediment cores were collected from Dillon Reservoir in 1997. The sediment cores were analyzed for pesticides, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and trace elements. Pesticides, PCBs, and PAHs were used to determine the effects of urban development, and trace elements were used to identify mining contributions. Water-quality and streambed-sediment samples, collected at the mouth of three streams that drain into Dillon Reservoir, were analyzed for trace elements. Of the 14 pesticides and 3 PCBs for which the sediment samples were analyzed, only 2 pesticides were detected. Low amounts of dichloro-diphenyldichloroethylene (DDE) and dichloro-diphenyldichloroethane (DDD), metabolites of dichlorodiphenyltrichloroethane (DDT), were found at core depths of 5 centimeters and below 15 centimeters in a core collected near the dam. The longest core, which was collected near the dam, spanned the entire sedimentation history of the reservoir. Concentrations of total combustion PAH and the ratio of fluoranthene to pyrene in the core sample decreased with core depth and increased over time. This relation is likely due to growth in residential and tourist populations in the region. Comparisons between core samples gathered in each arm of the reservoir showed the highest PAH concentrations were found in the Tenmile Creek arm, the only arm that has an urban area on its shores, the town of Frisco. All PAH concentrations, except the pyrene concentration in one segment in the core near the dam and acenaphthylene concentrations in the tops of three cores taken in the reservoir arms, were below Canadian interim freshwater sediment-quality guidelines. Concentrations of arsenic, cadmium, chromium, copper, lead, and zinc in sediment samples from Dillon Reservoir exceeded the Canadian interim freshwater sediment-quality guidelines. Copper, iron, lithium, nickel, scandium, titanium, and vanadium concentrations in sediment samples decreased over time. Other elements, while no trend was evident, displayed concentration spikes in the down-core profiles, indicating loads entering the reservoir may have been larger than they were in 1997. The highest concentrations of copper, lead, manganese, mercury, and zinc were detected during the late 1970's and early 1980's. Elevated concentrations of trace elements in sediment in Dillon Reservoir likely resulted from historical mining in the drainage area. The downward trend identified for copper, iron, lithium, nickel, scandium, titanium, and vanadium may be due in part to restoration efforts in mining-affected areas and a decrease in active mining in the Dillon Reservoir watershed. Although many trace-element core-sediment concentrations exceeded the Canadian probable effect level for freshwater lakes, under current limnological conditions, the high core-sediment concentrations do not adversely affect water quality in Dillon Reservoir. The trace-element concentrations in the reservoir water column meet the standards established by the Colorado Water Quality Control Commission. Although many trace-element core-sediment concentrations exceeded the Canadian probable effect level for freshwater lakes, under current limnological conditions, the high core-sediment concentrations do not adversely affect water quality in Dillon Reservoir. The trace-element concentrations in the reservoir water column meet the standards established by the Colorado Water Quality Control Commission.

Greve, Adrienne I.; Spahr, Norman E.; Van Metre, Peter C.; Wilson, Jennifer T.

2001-01-01

385

Elemental Analysis of Water and Sediments by External Beam Pixe Part 3: Axios (Vardar) River, Greece  

Microsoft Academic Search

The Axios (Vardar) River originates from the south west part of Yugoslavia, transverses Greece, and discharges into the Thermaikos bay in the north Aegean Sea.The proton induced X-ray emission (PIXE) method with external beam was used for the elemental analysis of water and sediment samples, while measurements of water temperature, dissolved oxygen content, conductivity, pH, and the water flow were

E. Papadopoulou-mourkidou; G. A. Mourkides; A. A. Katsanos; P. K. Kakanis

1986-01-01

386

Measured and modelled effects of temperature, dissolved oxygen and nutrient concentration on sediment-water nutrient exchange  

Microsoft Academic Search

Empirical models of sediment-water fluxes of NH4+, NO3- were and PO43- were formed based on published reports. The models were revised and parameters evaluated based on laboratory incubations of sediments collected from Gunston Cove, VA. Observed fluxes ranged from — 18 (sediments uptake) to 276 (sediment release) mg NH4+ m-2 day-1, -17 to -509 mg NO3- m-2 day-1, and -16.4

Carl F. Cerco

1989-01-01

387

Phthalate esters in water and sediments of the Kaveri River, India: environmental levels and ecotoxicological evaluations.  

PubMed

Phthalate esters are well known for their environmental contamination and toxicological effects as "endocrine disruptors." In this study, environmental levels of phthalate esters and ecotoxicological risk assessments were performed in one of the major rivers in India, the Kaveri. Water and sediment samples were collected during 2010-2012 representing the major stretch of the river and extracted by solid-phase and ultrasonic methods, respectively, and analyzed for six major phthalates by using a gas chromatograph-mass spectrometer. The analytical recovery for phthalates in water and sediment ranged from 79 to 121%. Results indicated that diethyl phthalate (DEP) and dimethyl phthalate were found in every sample, whereas butylbenzyl phthalate and diethylhexyl phthalate (DEHP) were detected in 92% of the water samples. Likewise, in sediment samples, DEP was found most often (94%). The total phthalates in water samples ranged from 313 to 1,640 ng/l, whereas in sediments it was 2 to 1,438 ng/g dw (dry weight) with DEHP having the highest concentration. Human health risk assessment based on drinking water consumption showed no potential risk for phthalates and also DEHP levels were safe with respect to USEPA guideline (6,000 ng/l). Further, DEHP and di-n-octyl phthalate levels in water were expected to pose little threat to sensitive organisms in the riverine ecosystem as per ECOSAR chronic values. In case of sediment, the DEHP concentration was well above the USEPA sediment guideline value. To our knowledge, this is the first study to describe the levels and ecotoxicological risks of phthalates in Kaveri River, India. PMID:25056812

Selvaraj, Krishna Kumar; Sundaramoorthy, Gomathy; Ravichandran, Praveen Kumar; Girijan, Girish Kumar; Sampath, Srimurali; Ramaswamy, Babu Rajendran

2015-02-01

388

Aquatic Sediments.  

ERIC Educational Resources Information Center

Presents a literature review of aquatic sediments and its effect upon water quality, covering publications of 1976-77. This review includes: (1) sediment water interchange; (2) chemical and physical characterization; and (3) heavy water in sediments. A list of 129 references is also presented. (HM)

Sanville, W. D.; And Others

1978-01-01

389

Optimization of analytical methods to improve detection of erythromycin from water and sediment.  

PubMed

Analytical methods to improve the detection of erythromycin in water and sediment were developed to optimize for erythromycin's recovery of extractable and bound residues from the aquatic environment. The objective of this study was to determine optimal recovery of erythromycin from water and sediment to improve its detection in environmental samples through solid-phase extraction (SPE) and sediment-extraction methods. SPE methods examined included previously reported methods for macrolide and sulfonamide antibiotics with erythromycin recoveries ranging from 75.5 % to 94.7 %. Extraction of erythromycin was performed from sand employing various solvents and buffers to determine the best method for extraction from two sandy loam pond sediments. Various extraction times were also examined, and all extraction procedures were performed in duplicate. The greatest recovery of (14)C-erythromycin in the Iowa sediment was 84 % using 0.3 M ammonium acetate at pH 4.2: acetonitrile (15:85, v/v) solution. The Oklahoma sediment yielded the greatest recovery of (14)C-erythromycin at 86.7 % with 0.3 M ammonium acetate at pH 7: acetonitrile (30:70, v/v) with a 60-minute shake time. The present results demonstrate improved extraction methods for enhancing the accuracy of erythromycin detection from environmental samples. PMID:21877980

Jessick, Ashley M; Moorman, Thomas B; Coats, Joel R

2011-01-01

390

A Coupled Biogeochemical Reactive Transport Model in Bed Sediments and Water Column of Riverine Systems  

NASA Astrophysics Data System (ADS)

ABSTRACT: A multi-scale, quasi-two-dimensional, biogeochemical reactive theoretical and numerical model is presented, able to simulating sediment associated transport and transformations of contaminants in the water column and bed sediments of riverine systems as a result of sediment associated transport, as well as resuspension, deposition and burial. The model considers contaminant mass exchange between sediments and aqueous phase both in benthic sediments and water column as a kinetically controlled process. It also takes into account the effect of microbially-mediated redox reactions affecting the speciation of chemicals. Transport of species in the sediments is modeled using a set of vertical one-dimensional sub-models which take into account the reactive transport of chemicals, burial, sorption/desorption to/from the solid phase, and diffusive transport of aqueous species. An innovative multi-time step approach is used to model the fully kinetic nonlinear reaction terms using a non-iterative explicit method. This approach enables the model to handle fast and near- equilibrium reactions without a significant increase in computational burden. Ongoing and planned applications of this multiscale modeling strategy to two cases, multiple metal transport in Lake Coeur d'Alene, Idaho, and Mercury Cycling in Walker Creek, California, are discussed.

Massoudieh, A.; Bombardelli, F. A.; Sengor, S. S.; Ginn, T. R.

2007-12-01

391

Water and sediment transport modeling of a large temporary river basin in Greece.  

PubMed

The objective of this research was to study the spatial distribution of runoff and sediment transport in a large Mediterranean watershed (Evrotas River Basin) consisting of temporary flow tributaries and high mountain areas and springs by focusing on the collection and use of a variety of data to constrain the model parameters and characterize hydrologic and geophysical processes at various scales. Both monthly and daily discharge data (2004-2011) and monthly sediment concentration data (2010-2011) from an extended monitoring network of 8 sites were used to calibrate and validate the Soil and Water Assessment Tool (SWAT) model. In addition flow desiccation maps showing wet and dry aquatic states obtained during a dry year were used to calibrate the simulation of low flows. Annual measurements of sediment accumulation in two reaches were used to further calibrate the sediment simulation. Model simulation of hydrology and sediment transport was in good agreement with field observations as indicated by a variety of statistical measures used to evaluate the goodness of fit. A water balance was constructed using a 12 year long (2000-2011) simulation. The average precipitation of the basin for this period was estimated to be 903 mm yr(-1). The actual evapotranspiration was 46.9% (424 mm yr(-1)), and the total water yield was 13.4% (121 mm yr(-1)). The remaining 33.4% (302 mm yr(-1)) was the amount of water that was lost through the deep groundwater of Taygetos and Parnonas Mountains to areas outside the watershed and for drinking water demands (6.3%). The results suggest that the catchment has on average significant water surplus to cover drinking water and irrigation demands. However, the situation is different during the dry years, where the majority of the reaches (85% of the river network are perennial and temporary) completely dry up as a result of the limited rainfall and the substantial water abstraction for irrigation purposes. There is a large variability in the sediment yield within the catchment with the highest annual sediment yield (3.5 t ha(-1)yr(-1)) to be generated from the western part of the watershed. The developed methodology facilitated the simulation of hydrology and sediment transport of the catchment providing consistent results and suggesting its usefulness as a tool for temporary rivers management. PMID:25497675

Gamvroudis, C; Nikolaidis, N P; Tzoraki, O; Papadoulakis, V; Karalemas, N

2015-03-01

392

HPLC-PFD determination of priority pollutant PAHs in water, sediment, and semipermeable membrane devices  

USGS Publications Warehouse

High performance liquid chromatography coupled with programmable fluorescence detection was employed for the determination of 15 priority pollutant polycyclic aromatic hydrocarbons (PPPAHs) in water, sediment, and semipermeable membrane devices (SPMDs). Chromatographic separation using this analytical method facilitates selectivity, sensitivity (ppt levels), and can serve as a non-destructive technique for subsequent analysis by other chromatographic and spectroscopic techniques. Extraction and sample cleanup procedures were also developed for water, sediment, and SPMDs using various chromatographic and wet chemical methods. The focus of this publication is to examine the enrichment techniques and the analytical methodologies used in the isolation, characterization, and quantitation of 15 PPPAHs in different sample matrices.

Williamson, K.S.; Petty, J.D.; Huckins, J.N.; Lebo, J.A.; Kaiser, E.M.

2002-01-01

393

Managing dredged sediment placement in open-water disposal sites, Upper Chesapeake Bay  

USGS Publications Warehouse

The maintenance dredging of fine-grained sediment which accumulated in shipping channels in the Upper Chesapeake was discussed. The capacity of open-water sites was maximized in an environmentally acceptable manner to provide adequate time for the development of beneficial use or confined placement sites. The additional water column turbidity generated by dragging operations and bottom sediment movement during placement raised environmental concerns which weighted against the need to maximize capacity. The inter-agency team overseeing site management provided a mechanism to implement operational changes which maximized site capacity and insured operational use through the projected life span of the site.

Panageotou, W.

2002-01-01

394

Natural and artificial radionuclides in the Suez Canal bottom sediments and stream water  

NASA Astrophysics Data System (ADS)

Concentration of natural and artificial radionuclides in Suez Canal bottom sediments and stream water have been measured using ? spectrometers based on a hyper-pure Ge detector. The activity concentrations of 238U series, 232Th series and 40K did not exceed 16.0, 15.5 and 500.0 Bq kg-1 dry weight for sediments. The activity concentration of 238U series and 40K did not exceed 0.6 and 18.0 Bq 1-1 for stream water.

El-Tahawy, M. S.; Farouk, M. A.; Ibrahiem, N. M.; El-Mongey, S. A. M.

1994-07-01

395

Determination of polychlorinated biphenyl congeners in water and sediment in North West Persian Gulf, Iran.  

PubMed

Polychlorinated biphenyl (PCB) was detected as isomer groups (congener numbers 28, 52, 101, 118, 138, 153 and 180) in the coastal water and sediment of four stations around Shadegan wetland protected area in the northwestern part of the Persian Gulf. Total PCB concentration range was 8-375 ng/L in water and 3.4-50.2 ?g/g in sediment. Concentration of different congeners and chromatogram indicates that the source of PCB in this area can be Clophen A60; it used for long time in Iranian electronic industries. Other chlorinated hydrocarbons such as lindane, DDT and their metabolites were also present in the samples. PMID:19760353

Zahed, M A; Nabi Bidhendi, Gh; Pardakhti, A; Esmaili-Sari, A; Mohajeri, S

2009-12-01

396

Solar heating and domestic hot water system installed at Kansas City, Fire Station, Kansas City, Missouri. Final report  

SciTech Connect

This document is the final report of the solar energy heating and hot water system installed at the Kansas City Fire Station, Number 24, 2309 Hardesty Street, Kansas City, Missouri. The solar system was designed to provide 47 percent of the space heating, 8800 square feet area and 75 percent of the domestic hot water (DHW) load. The solar system consists of 2808 square feet of Solaron, model 2001, air, flat plate collector subsystem, a concrete box storage subsystem which contains 1428 cubic feet of 1/2 inch diameter pebbles weighing 71 1/2 tons, a DHW preheat tank, blowers, pumps, heat exchangers, air ducting, controls and associated plumbing. Two 120-gallon electric DHW heaters supply domestic hot water which is preheated by the solar system. Auxiliary space heating is provided by three electric heat pumps with electric resistance heaters and four 30-kilowatt electric unit heaters. There are six modes of system operation. This project is part of the Department of Energy PON-1 Solar Demonstration Program with DOE cost sharing $154,282 of the $174,372 solar system cost. The Final Design Review was held March 1977, the system became operational March 1979 and acceptance test was completed in September 1979.

None

1980-07-01

397

Characterization of domestic gray water from point source to determine the potential for urban residential reuse: a short review  

NASA Astrophysics Data System (ADS)

This study aims to discern the domestic gray water (GW) sources that is least polluting, at the urban households of India, by examining the GW characteristics, comparing with literature data, reuse standards and suitable treatment technologies. In view of this, the quantitative and qualitative characteristics of domestic GW originating from bath, wash basin, laundry and kitchen sources are determined and compared with established standards for reuse requirements. Quality of different gray water sources is characterized with respect to the physical, chemical, biological, nutrient, ground element and heavy metal properties. The pollutant loads indicate that the diversion techniques are not suitable for household application and, therefore, treatment is necessary prior to storage and reuse. It is observed that the total volume of GW generated exceeds the reuse requirement for suggested reuse such as for flushing and gardening/irrigation. In spite of generating less volume, the kitchen source is found to be the major contributor for most of the pollutant load and, therefore, not recommended to be considered for treatment. It is concluded that treatment of GW from bathroom source alone is sufficient to meet the onsite reuse requirements and thereby significantly reduce the potable water consumption by 28.5 %. Constructed wetland systems and constructed soil filters are suggested as suitable treatment alternatives owing to its ability to treat highly variable pollutant load with lower operational and maintenance cost, which is more practical for tropical and developing countries.

Edwin, Golda A.; Gopalsamy, Poyyamoli; Muthu, Nandhivarman

2014-03-01

398

Sediment Mobilization From Reservoirs Can Cause Short Term Oxygen Depletion In Downstream Receiving Waters  

NASA Astrophysics Data System (ADS)

Reservoir management can cause incidences of short-term sediment mobilization, e.g. during dam removal or drawdown for maintenance or habitat purposes. Much of the associated planning focuses on predicting, quantifying, and mitigating the physical impacts of sediment mobilization, transport, and deposition. Sediment pulses can cause multiple regulatory and management concerns, such as turbidity or suspended sediment concentrations that may exceed State standards, geomorphic change and effects on property or infrastructure, or wildlife impacts such as stress to fish via gill abrasion or burial of critical habitat. Water-quality issues associated with sediment mobilization, including nutrient and contaminant transport, are often given less attention, presumably because their effects are less immediate or because of resource constraints. Recent experience with large pulses of sediment from several western reservoirs involving dam removals and temporary drawdowns indicates that oxygen demand, leading to depletion of downstream dissolved oxygen (DO), can also be a significant short-term concern. During the October 2011 Condit Dam removal on the White Salmon River in Washington, DO in receiving waters about 4.5 km downstream of the dam dropped to less than 1 mg/L within 2 hours of the demolition; in response, salmonids were observed to be in distress, apparently gulping for air at the water surface. DO remained low for at least 24 hours in this reach, and dead fish were observed. In December 2012, during a drawdown designed to aid juvenile-salmonid migration through Fall Creek Reservoir in Oregon, DO dropped precipitously about 1.5 km downstream as turbidity peaked, and a muted DO decrease was also observed approximately 14 miles further downstream despite a large dilution from unaffected sources. Laboratory experiments and modeling using sediments from reservoirs proposed for removal on the Klamath River, California, demonstrated the likelihood for downstream DO depletion stemming from a combination of chemical (< 2 hr) and biological (days-weeks) oxidation processes, depending on rates of sediment mobilization. Such depletion could contribute to fish stress or mortality for tens of kilometers downstream of the dams and for the duration of the sediment mobilization. Although modeling DO demand and measuring stream DO response during periods of elevated sediment concentration remains an area requiring further research, planning for large sediment mobilizing events could better anticipate and mitigate short-term, acute stresses on fish and aquatic life by recognizing the potential for transient, but significant, DO-related impacts.

Anderson, C.; Schenk, L.; Bragg, H.; Singer, M.; Hume, N.

2013-12-01

399

Potential of solar domestic hot water systems in rural areas for greenhouse gas emission reduction in Poland  

NASA Astrophysics Data System (ADS)

Application of solar energy for preparing domestic hot water is one of the easiest methods of utilization of this energy. At least part of the needs for warm tap water could be covered by solar systems. At present, mainly coal is used for water heating at dwellings in rural areas in Poland. Warm tap water consumption will increase significantly in the future as standards of living are improved. This can result in the growth of electricity use and an increase in primary fuel consumption. Present and future methods of warm sanitary water generation in rural areas in Poland is discussed, and associated greenhouse gas (GHG) emissions are estimated. It is predicted that the emission of CO2 and NO x will increase. The emission of CO and CH4 will decrease because of changes in the structure of the final energy carriers used. The economic and market potentials of solar energy for preparing warm water in rural areas are discussed. It is estimated that solar systems can meet 30% 45% of the energy demand for warm water generation in rural areas at a reasonable cost, with a corresponding CO2 emission reduction. The rate of realization of the economic potential of solar water heaters depends on subsidies for the installation of equipment.

Skowronski, Pawel; Wisniewski, Grzegorz

1996-01-01

400

Heavy metals in sediments from canals for water supplying and drainage: mobilization and control strategies.  

PubMed

One of the most critical aspects of the maintenance of canals for water supplying and drainage is the managing of deposited sediments, which must be periodically removed. Deposited sediments, if containing anthropogenic pollutants with a concentration exceeding specific law limits, must be stored as industrial wastes, thus raising additional economic and logistic problems to deal with. Our research considers polluted sediments from an area close to the south side of Po river, in order to characterize heavy metals associated with different mineral species, thus defining effective treatments for their inertization, and suggesting a possible process for their recycle. Our results demonstrate that the composition of these sediments is suitable for the production of tiles and bricks. Several tests were thus performed to optimize sample treatment and other process parameters, finally giving very encouraging results. Releasing tests on fired products reveal that all the heavy metals are well retained. PMID:18486335

Malferrari, Daniele; Brigatti, Maria Franca; Laurora, Angela; Pini, Stefano

2009-01-30

401

Impact of water column acidification on protozoan bacterivory at the lake sediment-water interface  

SciTech Connect

Although the impact of acidification on planktonic grazer food webs has been extensively studied, little is known about microbial food webs either in the water column or in the sediments. Protozoan-bacterium interactions were investigated in a chronically acidified (acid mine drainage) portion of a lake in Virginia. The authors determined the distribution, abundance, apparent specific grazing rate, and growth rate of protozoa over a pH range of 3.6 to 6.5. Protozoan abundance was lower at the most acidified site, while abundance, in general, was high compared with other systems. Specific grazing rates were uncorrelated with pH and ranged between 0.02 and 0.23 h{sup {minus}1}, values similar to those in unacidified systems. The protozoan community from an acidified station was not better adapted to low-pH conditions than a community from an unacidified site (multivariate analysis of variance on growth rates for each community incubated at pHs 4, 5, and 6). Both communities had significantly lower growth rates at pHs 4 and 5 than at pH 6. Reduced protozoan growth rates coupled with high grazing rates and relatively higher bacterial yields (ratio of bacterial-protozoan standing stock) at low pH indicate reduced net protozoan growth efficiency and a metabolic cost of acidification to the protozoan community. However, the presence of an abundant, neutrophilic protozoan community and high bacterial grazing rates indicates that acidification of Lake Anna has not inhibited the bacterium-protozoan link of the sediment microbial food web.

Tremaine, S.C.; Mills, A.L. (Univ. of Virginia, Charlottesville (USA))

1991-03-01

402

Occurrence of arsenic in sediment pore waters in the central Kanto Plain, Japan  

NASA Astrophysics Data System (ADS)

The Kanto Plain is known as the largest plain in Japan, where marine sediments are widely developed because of cyclic iteration of global sea-level changes even 50 km or more inland from the present shoreline. In this area, dependence on groundwater for water requirements is relatively high; in particular, around 40 % of the municipal water supply is dependent on groundwater. Arsenic levels greater than that permitted by the environmental standards of Japan have been detected in groundwater in this area. Therefore, to evaluate occurrences of arsenic and other related elements in pore waters contained in natural sediment layers, we measured the levels of various inorganic chemical substances such as arsenic (As), iron (Fe), and sulfur (S) and major dissolved ions such as sulfate (SO42-), calcium (Ca2+), and sodium (Na+). Pore waters were collected from sediment samples that were obtained by a drilling from the river bottom down to 44 m depth; pore water samples were obtained immediately after extraction of sediments. The sedimentary facies in the vertical profile are continental, transitional, and marine, including two aquifers. The upper aquifer (15-20 m) contains fine to medium sand, whereas the lower aquifer (37-44 m) contains medium to coarse and gravelly sand. Arsenic and other inorganic elements were measured by an inductively coupled plasma mass spectrometer (ICP/MS) and an inductively coupled plasma atomic emission spectrometer (ICP/AES), and major dissolved ions were measured by an ion chromatograph analyzer. The total content of chemical elements was measured by X-ray fluorescence analysis using solid sediment samples. We obtained the following results. The arsenic concentrations in pore waters in marine silt and clay sediments (approximately 0.04 mg/L) were about five times higher than that in continental sediments (approximately 0.008 mg/L). The highest concentration of arsenic (0.074 mg/L) was detected at a depth of 13 m, which is immediately above the upper aquifer. Visual observations confirmed that this level is under oxidizing conditions. Thus, it regards that arsenic was adsorbed to iron hydroxide in the sediments. On the other hand, in the top part of the section, from the river bottom to a depth of approximately 3 m, arsenic concentrations in the pore waters were clearly high and decreased gradually and continuously with depth. This is considered to be the result of anthropogenic impact on the river.

Hachinohe, Shoichi; Hamamoto, Hideki; Ishiyama, Takashi; Hossain, Sushmita; Oguchi, Chiaki T.

2014-05-01

403

An evaluation of the OECD 308 water/sediment systems for investigating the biodegradation of pharmaceuticals.  

PubMed

In recent times, trace levels of pharmaceuticals detected in wastewater effluents and surface waters have raised the level of attention around the ultimate fate and the potential persistence of pharmaceuticals in the environment. We have seen the European Agency for the Evaluation of Medicines (EMEA) recently include more rigorous environmental fate testing in European Union (EU) Environmental Risk Assessment (ERA) guidance to assess the ultimate fate in water/sediment systems. Yet to date, there is little data available that covers the fate of pharmaceuticals in the water/sediment compartment, and little that assess whether current aerobic and anaerobic methods are appropriate for pharmaceuticals. In this study, the biodegradation profiles of 3 Pfizer products were investigated following the latest ERA guidance and its recommendation for OECD 308 water/sediment biodegradation testing. Experiments included 14C-labeled exemestane, azithromycin, and varenicline representing neutral and cationic pharmaceuticals with average K(oc) values of 3704, 49 400, and 10 483 respectively. Specific HPLC/radioactive monitoring (RAM) methods were used to profile water and sediment samples for biotransformation products. Binding to sediment, as "non-extractables", was considerable for all three pharmaceuticals, though most notable for the cationic pharmaceuticals varenicline and azithromycin ranging from 52% to 94% at study termination, respectively. In general, for all 3 pharmaceuticals studied, the anaerobic conditions demonstrated less biotransformation and mineralization than the aerobic; though their biotransformation profile (number of metabolites) and amount bound to sediment were similar. Based on these findings and our current understanding of anaerobic biodegradation, we would recommend a tiered approach to the OECD 308 water/ sediment test: with default testing just for aerobic conditions; and then if needed, anaerobic testing only for those compounds potentially amenable to typical anaerobic processes. We suggest that as a simulation test would be better suited in later tier testing under EU ERA guidance. Inherent biodegradation or die-away tests seem better suited to derive biodegradation rate constants for subsequent environmental modeling of water and sediment compartments. PMID:17874790

Ericson, Jon F

2007-08-15

404

Widespread potential for microbial MTBE degradation in surface-water sediments  

USGS Publications Warehouse

Microorganisms indigenous to stream and lake bed sediments, collected from 11 sites throughout the United States, demonstrated significant mineralization of the fuel oxygenate, methyl-tert-butyl ether (MTBE). Mineralization of [U-14C]MTBE to 14CO2 ranged from 15 to 66% over 50 days and did not differ significantly between sediments collected from MTBE contaminated sites and from sites with no history of MTBE exposure. This result suggests that even the microbial communities indigenous to newly contaminated surface water systems will exhibit some innate ability to attenuate MTBE under aerobic conditions. The magnitude of MTBE mineralization was related to the sediment grain size distribution. A pronounced, inverse correlation (p < 0.001; r2 = 0.73) was observed between the final recovery of 14CO2 and the percentage content of silt and clay sized grains (grain diameter < 0.125 mm). The results of this study indicate that the microorganisms that inhabit the bed sediments of streams and lakes can degrade MTBE efficiently and that this capability is widespread in the environment. Thus aerobic bed sediment microbial processes may provide a significant environmental sink for MTBE in surface water systems throughout the United States and may contribute to the reported transience of MTBE in some surface waters.

Bradley, P.M.; Landmeyer, J.E.; Chapelle, F.H.

2001-01-01

405

Field measurement of diffusional mass transfer of HOCs at the sediment-water interface.  

PubMed

The sediment to water diffusive flux of PAHs and PCBs was measured under field conditions with a novel infinite-sink benthic flux chamber that deployed semipermeable membrane devices (SPMD) as a sorbing material. Fluxes were measured before and after in situ capping of sediments in Oslo Harbour with clean clay. The fluxes of native pyrene and PCB 52 from uncapped contaminated sediment measured with the flux chamber were 0.3-1.6 microg m(-2) d(-1) and 2-8 ng m(-2) d(-1), respectively. Fluxes from the capped sediment were reduced by 93-97%. The in situ measured fluxes were compared to fluxes independently calculated from freely dissolved concentrations in pore water and overlying water, measured using equilibrium passive samplers, diffusive boundary layer (DBL) thickness, measured by an alabaster dissolution method and literature values of diffusion coefficients. Measured fluxes from the uncapped sediment agreed well with calculated fluxes, the median of the ratio of the measured flux over the calculated flux was 0.9 with an inter quartile range of 0.5-1.6. PMID:20704281

Eek, Espen; Cornelissen, Gerard; Breedveld, Gijs D

2010-09-01

406

Spatial and temporal trends in surface water and sediment contamination in the Laurentian Great Lakes.  

PubMed

Data from recent sediment and surface water surveys have been collated and mapped to illustrate the spatial distribution of contaminants across the entire Great Lakes basin. Information from historical surveys, together with data from surface water monitoring programs in three major connecting channels, has also been collated in order to evaluate temporal trends. In general, Lakes Superior and Michigan exhibited the lowest levels of sediment contamination while Lake Ontario had the highest. Contaminants such as gamma-HCH (lindane) and dieldrin were ubiquitous in surface waters across the entire basin, which was indicative of atmospheric sources. The distribution of other compounds including hexachlorobenzene, octachlorostyrene and mirex indicated the presence of local sources within the watersheds of the connecting channels. Surficial sediment contamination was found to have decreased markedly since the late 1960s and 1970s. Similarly, surface water contamination decreased over the period 1986-1997 with concentrations of dieldrin, hexachlorobenzene, octachlorostyrene and mirex reduced by over 50%. However, the spatial distributions of both sediment and surface water contamination indicate that further effort is warranted in reducing local sources of contaminants, particularly in Lake Ontario. PMID:14749077

Marvin, Chris; Painter, Scott; Williams, Donald; Richardson, Violeta; Rossmann, Ronald; Van Hoof, Patricia

2004-05-01

407

Estrogenic compounds and estrogenicity in surface water, sediments, and organisms from Yundang Lagoon in Xiamen, China.  

PubMed

Seven estrogenic compounds--estrone (E1), 17?-estradiol (E2), 17?-ethynylestradiol (EE2), diethylstilbestrol (DES), nonylphenol (NP), octylphenol (OP), and bisphenol A (BPA)--in sediments, surface water, pore water, and organisms were investigated and estrogenic activities were estimated by examining estradiol equivalent (EEQ) concentrations in Yundang Lagoon of Xiamen. The results showed that estrogenic compounds were present in all matrixes of interest: in surface water, ranging from 609.61 to 711.31 ng/l; in pore water, ranging from 562.12 to 1038.15 ng/l; in sediments, ranging from 1433.12 to 2060.41 ng/g; and in biota samples, ranging from 1373.76 to 3199.09 ng/g (lipid weight). NP was the predominant component in all collected samples and the highest concentration was 1964.80 ng/g in sediment. Total EEQ ranged from 4.56 to 13.79 ng/l in surface water, from 2.40 to 17.16 ng/l in pore water, and from 8.66 to 23.95 ng/g in sediments. However, major contributors to total EEQ concentrations were E2, E1, and DES. The EEQ concentrations in surface water samples were at a higher level in comparison to that reported in European countries. To biological sample, the highest level of total estrogenic compounds was found in the short-necked clam. Higher values of the biota-sediment accumulation factor (BSAF) were found in short-necked clam and black seabream, indicating that the living habits of organism and physical-chemical properties of estrogenic compounds might influence the bioavailability of estrogenic compounds in organisms. PMID:20725718

Zhang, Xian; Gao, Yajie; Li, Qingzhao; Li, Guoxin; Guo, Qinghai; Yan, Changzhou

2011-07-01

408

Water and sediment dynamics at Saint Lawrence River mouth  

Microsoft Academic Search

The main features of the hydrological regime and morphological structure of the estuarine-type mouth area of the Saint Lawrence\\u000a River are considered. Data on the structure of water masses, thermal and ice regimes in the Gulf of Saint Lawrence, which\\u000a has a significant effect on the estuary, are given. The major attention is paid to water mixing processes, water and

E. N. Dolgopolova; M. V. Isupova

2011-01-01

409

Heat and dissolved oxygen exchanges between the sediment and water column in a shallow salty lagoon  

NASA Astrophysics Data System (ADS)

Dissolved oxygen (DO) and heat exchanges across the water-sediment interface (WSI) of a shallow lagoon are controlled by processes occurring on both sides of the WSI, particularly volumetric source and sink on the sediment side and turbulent transport on the waterside. This article presents and analyzes measurements of DO (Js) and heat (Hg) fluxes across the WSI in the extremely shallow lagoon of Salar del Huasco (20.274°S, 68.883°W, 3800 m above sea level), where volumetric source of DO and heat exists in the sediment layer, related to benthic primary production and absorption of solar radiation, respectively. Microprofiles of temperature and DO were measured, and they were used for measuring Js and Hg, and volumetric source/sink terms in the sediments. This information was used to propose and validate the simple theoretical framework to predict both the magnitude and direction of Js and Hg. On the one hand, Js can be predicted with a simple algebraic expression, where the diffusional mass transfer coefficient defines the magnitude of Js while the direction is controlled by the balance between DO production and consumption in the sediments. On the other hand, solar radiation is absorbed in the upper sediments, and this heat diffuses toward the water column and the sediments. The heat flux toward the water column also induces unstable convection that promotes vertical transport across the WSI. The theoretical framework proposed here will help to understand DO and heat budgets of shallow aquatic systems in which solar radiation reaches the WSI.

Fuente, Alberto

2014-04-01

410

34. GEOCHEMISTRY OF SEDIMENTS AND INTERSTITIAL WATERS FROM OKI RIDGE AND KITA-YAMATO TROUGH, JAPAN SEA1  

Microsoft Academic Search

Interstitial waters in sediments below 400 (Site 798) and 435 meters below seafloor (Site 799) have chloride concentrations of 516-527 and 501-515 mM, respectively, lower than the 540 mM of the modern-day Japan Sea. The chemical composition of interstitial waters, bulk sediments, clay-size sediment fraction, and carbonate nodules from Oki Ridge (Site 798) and Kita-Yamato Trough (Site 799), Japan Sea,

Anne A. Sturz; Barry B. Hanan; Guy Emanuele

411

Experimental investigation of factors controlling the calcium carbonate ion activity product of shallow water carbonate-rich sediments  

E-print Network

sediment samples with sea- water to gain an equilibrium solubility product for calcium carbonate. He failed to recognize that this would represent a metastable equilibrium due to the complex nature of the sediments. Dynamic processes...EXPERIMENTAL INVESTIGATION OF FACTORS CONTROLLING THE CALCIUM CARBONATE ION ACTIVITY PRODUCT OF SHALLOW WATER CARBONATE-RICH SEDIMENTS A Thesis by LAWRENCE DOUGLAS BERNSTEIN Submitted to the Graduate College of Texas A&M University...

Bernstein, Lawrence Douglas

1983-01-01

412

Contribution of 222Rn in domestic water supplies to 222Rn in indoor air in Colorado homes  

USGS Publications Warehouse

The contribution of 222Rn from domestic water wells to indoor air was investigated in a study of 28 houses near Conifer, CO. Air concentrations determined by alpha-track detectors (ATDs) and continuous radon monitors were compared with the predictions of a single-cell model. In many of the houses, the water supply was shown to contribute significantly to levels of indoor 222Rn. The data from the ATD study were augmented with a continuous monitoring study of a house near Lyons, CO. The well water in that house has the highest known concentration of 222Rn in water yet reported (93 MBq m-3). The temporal pattern in the indoor 222Rn concentration corresponds to water-use records. In general, it is difficult to quantify the proportion of indoor radon attributable to water use. Several lines of evidence suggest that the single-cell model underestimates this proportion. Continuous- monitoring data, although useful, are impractical due to the cost of the equipment. We propose a protocol for 222Rn measurement based on three simultaneous integrating radon detectors that may help estimate the proportion of indoor 222Rn derived from the water supply.

Lawrence, E.P.; Wanty, R.B.; Nyberg, P.

1992-01-01

413

Critical velocity in phosphorus exchange processes across the sediment-water interface.  

PubMed

Sediments are ultimate sinks of nutrients in lakes that record the pollution history evolutionary processes, and anthropogenic activities of a lake. However, sediments are considered as inner sources of environmental factor changes such as the variation in hydrodynamic conditions because of the nutrients they release. How does this process happen? This study investigates a typical nutrient phosphorus (P) exchange among sediment, suspended particle matter (SPM), and water. Compared with numerical and experimental studies, this study confirms that the critical velocity that occurs at a lower flow rate state exists in the range of 7 to 15 cm/sec. Critical velocity below the critical flow rate promotes the migration of particulate phosphorus (PP) to the SPM. On the other hand, critical velocity above the critical flow rate promotes the release of PP in water. PMID:24494482

Wan, Jun; Wang, Ze; Li, Zhijie; Duan, Huiling; Hezhong, Yuan

2013-10-01

414

Sediment discharge in the Lake Tahoe basin, California, 1972 water year  

USGS Publications Warehouse

Streamflow and fluvial-sediment discharge data are being collected at selected streams and highway gutters in the Lake Tahoe basin to determine the extent of erosion from highway cuts and to evaluate the effects of various land treatment practices to reduce erosion. Precipitation in the Lake Tahoe area during 1972 was 77 percent of normal; consequently, runoff was well below normal. Seventy-six percent of the total annual runoff during the 1972 water year occurred from March through June 1972. Sediment samples were collected during the year at streamflow gaging stations and at gutter stations at highway cuts to define the range of transport conditions. The major part (87 percent) of the annual suspended-sediment discharge during the 1972 water year occurred during the snowmelt runoff period, March through June.

Kroll, Carl G.

1973-01-01

415

NUMERICAL MODELING OF WATER QUALITY AND SEDIMENT RELATED PROCESSES  

Technology Transfer Automated Retrieval System (TEKTRAN)

A three-dimensional water quality model was developed for simulating temporal and spatial variations of water quality with respect to phytoplankton, nutrients, and dissolved oxygen. Four major interacting systems were simulated, including phytoplankton dynamics, the nitrogen and phosphorus cycles, a...

416

Enzyme activities in the water column and in shallow permeable sediments from the northeastern Gulf of Mexico  

Microsoft Academic Search

The activities of extracellular enzymes that initiate the microbial remineralization of high molecular weight organic matter were investigated in the water column and sandy surface sediments at two sites in the northeastern Gulf of Mexico. Six fluorescently labeled polysaccharides were hydrolyzed rapidly in the water column as well as in permeable sediments. This result contrasts with previous studies carried out

C. Arnosti; K. Ziervogel; L. Ocampo; S. Ghobrial

2009-01-01

417

Toxicity identification evaluation of metal-contaminated sediments using an artificial pore water containing dissolved organic carbons  

Microsoft Academic Search

Recent investigations of sediment-associated pollutants in Lake Champlain indicated significant contamination with As, Mn, and Ni in Outer Malletts Bay, Vermont, US. Ceriodaphnia dubia exposed to sediment pore water from several sites in Outer Malletts Bay showed repeatable, acute mortality at only one site. A toxicity identification evaluation (TIE) was conducted on pore water to determine the contaminants causing mortality

Anne M. Boucher; Mary C. Watzin

1999-01-01

418

Ambient water and sediment quality of Galveston Bay: Present status and historical trends. Volume 1. Final report  

Microsoft Academic Search

For many years, data relating to the quality of water and sediment have been collected in the Galveston Bay system by a variety of organizations and individuals. The purpose of the project was to compile these data, and to perform a quantitative assessment of water and sediment quality of Galveston Bay and its evolution over time. The study focused on

G. H. Ward; N. E. Armstrong

1992-01-01

419

The nature of metals---sediment---water interactions in freshwater bodies, with emphasis on the role of organic matter  

Microsoft Academic Search

A review with 227 references of the title subject is presented. It is divided into two main sections, viz., nature and properties of humic matter, and water---metal---sediment interactions. The first section deals with the essential properties of organic matter which occurs naturally in drainage sediments and waters. Discussion of the basic molecular structure of humic and fulvic acids is followed

K. S. Jackson; I. R. Jonasson; G. B. Skippen

1978-01-01

420

Water and sediment quality assessment of the Axios River and its coastal environment  

NASA Astrophysics Data System (ADS)

The Axios River (Axios R.) receives substantial loads of nutrients, heavy metals and other compounds, resulting from anthropogenic activities within its catchment. Long-term trends in nutrients were assessed. Dissolved and particulate fluxes of nutrients and selected metals to the Thermaikos Gulf were calculated and finally, data evaluation with water and sediment quality criteria was performed. Dissolved nutrient concentrations exhibited intra-annual variations related to the agricultural practices of the drainage area with elevated autumn-winter NO 3 concentrations (related to fertilizers applied early spring) and high levels of total phosphorous in the summer attributed to point source pollution. Long-term inter-annual variability showed a 2.5-fold increase in nitrate concentration, coupled with a 3-fold decrease in water discharge. Elevated concentrations of dissolved Pb and As have been observed in the Axios R., and freshwater quality criteria for Pb were exceeded. Stream sediments exhibited high contents for Zn, Cr, Pb, and As, mainly originating in tailings and industrial effluents. On the other hand, a considerable portion of the heavy metals is derived from the weathering of ultra-mafic ophiolite complexes. Similar patterns were observed in the Thermaikos Gulf sediment chemistry; the geochemical signatures of the Axios and Aliakmon Rivers (Aliakmon R.), in respect to their contribution in heavy metals, were identified, as well as the impact of the Thessaloniki city. Quality criteria for both river and marine sediments were violated for As and Cr. Overall, the water and sediment quality of the Axios R. and the Thermaikos Gulf have been impacted by anthropogenic activities in the hinterland. The coastal waters and sediments do not appear to pose any threat to human health and aquatic life, however, the need for regular monitoring is highly recommended.

Karageorgis, A. P.; Nikolaidis, N. P.; Karamanos, H.; Skoulikidis, N.

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