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Sample records for water sediment domestic

  1. Contaminated Sediments in Water

    MedlinePLUS

    ... Contact Us Water: Contaminated Sediments You are here: Water Pollution Prevention & Control Sediments Contaminated Sediments in Water Contaminated ... Water Education & Training Grants & Funding Laws & Regulations Our Waters Pollution Prevention & Control Applications & Databases Low Impact Development Impaired ...

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

    PubMed

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

    2014-11-01

    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

  3. Domestic wash water reclamation

    NASA Technical Reports Server (NTRS)

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

    1974-01-01

    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.

  4. Water-Using Equipment: Domestic

    SciTech Connect

    Solana, Amy E.; Mcmordie, Katherine

    2006-01-24

    Water management is an important aspect of energy engineering. This article addresses water-using equipment primarily used for household purposes, including faucets, showers, toilets, urinals, dishwashers, and clothes washers, and focuses on how the equipment can be optimized to save both water and energy. Technology retrofits and operation and maintenance changes are the primary methods discussed for water and energy conservation. Auditing to determine current consumption rates is also described for each technology.

  5. Economic valuation of domestic water uses.

    PubMed

    Justes, Antn; Barbern, Ramn; Farizo, Begoa A

    2014-02-15

    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

  6. Ballast water sediment elemental analysis.

    PubMed

    Maglić, Lovro; Zec, Damir; Frančić, Vlado

    2016-02-15

    Sediment samples from the ballast water tanks of ships calling at the port of Rijeka in the Northern Adriatic were analysed using X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS) using caesium, argon and oxygen ion beams. The research was carried out in order to determine the sediment composition and relative abundance of the dominant elements. The results indicate that the sediment samples mostly consisted of compounds that originated from the deterioration of tank plates, tank coating residues and ballast operations such as clay, silt, sand and organic materials. No significant heavy metals or highly toxic elements were found. The research revealed some advantages and significant drawbacks of using XPS and SIMS for the routine analysis of sediment composition as a decision supporting tool for ballast water and sediment management. PMID:26763315

  7. 9. SEDIMENTATION CHAMBER, VIEW DOWNSTREAM. AFTER SEDIMENTATION, WATER FLOWS INTO ...

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

    9. SEDIMENTATION CHAMBER, VIEW DOWNSTREAM. AFTER SEDIMENTATION, WATER FLOWS INTO ONE 8" CAST-IRON PIPELINE. - Kalaupapa Water Supply System, Waikolu Valley to Kalaupapa Settlement, Island of Molokai, Kalaupapa, Kalawao County, HI

  8. Quantifying Urban Water Subsidies with Hydrological Tracers of Domestic Water

    NASA Astrophysics Data System (ADS)

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

    2011-12-01

    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.

  9. Reutilization of industrial sedimentation plants as a domestic landfill

    SciTech Connect

    Viehweg, M.; Duetsch, M.; Wagner, J.; Edelmann, F.

    1995-12-31

    The methods and the investigation results for evaluation of the risk potential emanating from the mixed waste landfill Steinsee in Johanngeorgenstadt are described for the protected commodities of water, soil and air. The peculiarity of this mixed waste landfill is its layered structure (17th to 19th century near-surface mineworkings, granite weathering zone at the base of the landfill, washed-in tailings, and refuse dump). A network of measuring points has been installed in and around the landfill, and selective investigations have been made to ascertain the risk potential from the landfill. Based on the investigation results, it can be estimated that the continued use of the landfill is justifiable from the geological, hydrogeological and hydrological viewpoints, provided that permanent and continuous control is ensured by a monitoring system and that the overall situation can be improved in the short term by suitable technical measures. The waste being deposited now consists of domestic refuse, bulky refuse, sewage sludge, building rubble, excavated earth, broken up road surfacing, waste containing asbestos, industrial waste and power station ash.

  10. Accounting for Water Insecurity in Modeling Domestic Water Demand

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

    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.

  11. Domestic livestock resources of Turkey: water buffalo.

    PubMed

    Yilmaz, Orhan; Ertugrul, Mehmet; Wilson, Richard Trevor

    2012-04-01

    Water buffalo are an ancient component of Turkey's domestic livestock resources. Commonly referred to as the Anatolian buffalo the animal is part of the Mediterranean group which includes Syrian, Egyptian and Southeast European animals. Once quite numerous, there have been drastic reductions in their numbers since the 1970s due to intensification of dairy activities, agricultural mechanization and changing consumer preferences. The main areas of distribution are in northwest Turkey in the Marmara and Black Sea Regions. Buffalo are kept in small herds by livestock and mixed crop-livestock farmers. Milk is the main product, meat is largely a by-product of the dairy function and provision of the once-important draught power is now a minor output. Buffalo milk is used to prepare a variety of speciality products but output of both milk and meat is very low in comparison to cattle. Conditions of welfare and health status are not optimal. Internal parasites are a constraint on productivity. Some buffalo are being used for conservation grazing in the Black Sea area to maintain optimal conditions for bird life in a nature reserve. Long neglected by government there are recent activities to establish conservation herds, set up in vitro banks and undertake molecular characterization. More effort is needed by government to promote buffalo production and to engage the general public in conservation of their national heritage. PMID:21870064

  12. Inorganic chemicals in domestic water of the United Arab Emirates.

    PubMed

    Rizk, Zeinelabidin S

    2009-02-01

    The concentration of selected inorganic chemicals was determined for 396 samples of bottled water, desalinated water, and groundwater used for drinking and domestic purposes in the United Arab Emirates (UAE). The objective of this study was to compare the concentrations of inorganic chemicals in different domestic water types used in the UAE with the World Health Organization (WHO) limits for drinking water. Results of the present study revealed a wide variation in the concentrations of major, minor, and trace inorganic chemicals in domestic water of the UAE. For example, the bottled water sold for drinking is depleted in major ions and the total dissolved solids (TDS) in some brands do not exceed 100 mg/l. On the other hand, some of the domestic water used may contain as much as 3,000 mg/l TDS, which is above the WHO recommended limit for drinking water (500-1,500 mg/l TDS). Similarly, while bottled water is almost free of trace ions and minor constituents, some natural groundwater may have concentrations higher than the WHO recommended limits for drinking water. The cause of this variation is related to the different water sources and the large number of companies producing and distributing drinking and domestic water. Moreover, it is clear that the current controls on domestic water quality in some areas, namely conformance of pH and electrical conductivity measurements with prescribed ranges of values, are currently inadequate. These two parameters are not enough to judge if water is suitable for drinking or not and some consumers may receive domestic water of uncertain quality. PMID:18266056

  13. 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...

  14. Socioeconomic differentials and availability of domestic water in South Africa

    NASA Astrophysics Data System (ADS)

    Dungumaro, Esther W.

    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 peoples 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.

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

    PubMed

    Korfali, Samira Ibrahim; Jurdi, Mey

    2007-12-01

    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

  16. Sedimentation problem in water Conservancy in China

    SciTech Connect

    Wu, D.

    1984-12-01

    The state-of-the-art of river sedimentation management in China is reviewed. Attention is focused on the sediment load carried by main rivers in China; the related sediment problems encountered in developing water resources; and the methods in dealing with those problems. There are 50 rivers with annual maximum sediment load exceeding 10 million tons in China. There are more than 400,000 sq km of loess plateaus and hills in the drainage basin of the Yellow River. Inadequate conservation of soil and water leads to erosion, transportation and deposition of sediment, giving rise to much trouble in water conservation works. These problems include flood control, navigational concerns, reservoir sedimentation, and sediment problems of lowhead diversion dams or hydroelectric projects. Methods for dealing with sediment problems include water and soil conservation and use of turbid water with emphasis on terracing, strip cropping, forestation, grass and crop rotation. Several types of structures may be built along a gully such as small reservoirs, check dams, drop structures, drainage ditches, and irrigation canal systems for diverting hyperconcentrated flow into farmland or to warp land. Processes for diverting water while preventing sediment from entering water intakes at hydroelectric plants are becoming more advanced. 4 references, 3 figures, 2 tables.

  17. Domestic applications for aerospace waste and water management technologies

    NASA Technical Reports Server (NTRS)

    Disanto, F.; Murray, R. W.

    1972-01-01

    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.

  18. Acanthamoeba: keratopathogenicity of isolates from domestic tap water in Korea.

    PubMed

    Jeong, Hae Jin; Lee, Sun Joo; Kim, Jeong Hwan; Xuan, Ying Hua; Lee, Keun Hee; Park, Sang Kyun; Choi, Sun Hee; Chung, Dong Il; Kong, Hyun Hee; Ock, Mee Sun; Yu, Hak Sun

    2007-12-01

    In a previous study, we reported on the contamination rate of free living amoeba, including Acanthamoeba, isolated from contact lens storage cases (CLSC) and domestic tap water in Korea. In an effort to evaluate the potential kerato-pathogenicity of 5 isolates from CLSC and 17 isolates from domestic tap water, we have conducted an investigation into the morphological features, mitochondrial DNA (mtDNA) restriction fragment length polymorphism (RFLP) phenotypes, 18S rDNA sequences, and drug sensitivities of these isolates, and have compared the results with those of 20 amoebic keratitis (AK) isolates from Korea, as well as 14 reference strains. Cysts from 22 isolates obtained from CLSC and domestic tap water showed typical characteristics of morphological group 2. A total of three and five mtDNA RFLP patterns generated by EcoRI were found in 5 of the isolates from CLSC and 17 of the isolates from domestic tap water, respectively. The mtDNA RFLP patterns of four of the five isolates from the CLSC were found to be identical to those of the isolates from domestic tap water of students who had contaminated CLSC. The majority had mtDNA RFLP patterns identical to those of AK isolates in Korea. The results of 18S rDNA sequencing analysis were also shown to coincide with the results of mtDNA RFLP analysis. KA/WP12 was determined to be profoundly sensitive to chlorhexidine (MCC; 6.25microg/ml), and KAWP2 was the most sensitive strain to polyhexamethylene biguanide (PHMB) (MCC; 4.69microg/ml). Some difference in the cytopathic effects of isolates against human corneal epithelial cells was observed according to their mtDNA genotypes. In conclusion, domestic tap water may constitute a source of Acanthamoeba contamination of CLSC, and most isolates from CLSC and domestic tap water appear to be potentially keratopathogenic. PMID:17574243

  19. Design package for solar domestic hot water system

    NASA Astrophysics Data System (ADS)

    1980-09-01

    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.

  20. Analysis Model for Domestic Hot Water Distribution Systems: Preprint

    SciTech Connect

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

    2011-11-01

    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.

  1. Design package for solar domestic hot water system

    NASA Technical Reports Server (NTRS)

    1980-01-01

    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.

  2. Prototype solar domestic hot water systems

    NASA Technical Reports Server (NTRS)

    1978-01-01

    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.

  3. 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...

  4. Legionella Infection Risk from Domestic Hot Water

    PubMed Central

    Montagna, M. Teresa; Romano-Spica, Vincenzo; Stampi, Serena; Stancanelli, Giovanna; Triassi, Maria; Neglia, Rachele; Marchesi, Isabella; Fantuzzi, Guglielmina; Tat, Daniela; Napoli, Christian; Quaranta, Gianluigi; Laurenti, Patrizia; Leoni, Erica; De Luca, Giovanna; Ossi, Cristina; Moro, Matteo; DAlcal, Gabriella Ribera

    2004-01-01

    We investigated Legionella and Pseudomonas contamination of hot water in a cross-sectional multicentric survey in Italy. Chemical parameters (hardness, free chlorine, and trace elements) were determined. Legionella spp. were detected in 33 (22.6%) and Pseudomonas spp. in 56 (38.4%) of 146 samples. Some factors associated with Legionella contamination were heater type, tank distance and capacity, water plant age, and mineral content. Pseudomonas presence was influenced by water source, hardness, free chlorine, and temperature. Legionella contamination was associated with a centralized heater, distance from the heater point >10 m, and a water plant >10 years old. Furthermore, zinc levels of <20 ?g/L and copper levels of >50 ?g/L appeared to be protective against Legionella colonization. Legionella species and serogroups were differently distributed according to heater type, water temperature, and free chlorine, suggesting that Legionella strains may have a different sensibility and resistance to environmental factors and different ecologic niches. PMID:15109413

  5. Legionella infection risk from domestic hot water.

    PubMed

    Borella, Paola; Montagna, M Teresa; Romano-Spica, Vincenzo; Stampi, Serena; Stancanelli, Giovanna; Triassi, Maria; Neglia, Rachele; Marchesi, Isabella; Fantuzzi, Guglielmina; Tat, Daniela; Napoli, Christian; Quaranta, Gianluigi; Laurenti, Patrizia; Leoni, Erica; De Luca, Giovanna; Ossi, Cristina; Moro, Matteo; Ribera D'Alcal, Gabriella

    2004-03-01

    We investigated Legionella and Pseudomonas contamination of hot water in a cross-sectional multicentric survey in Italy. Chemical parameters (hardness, free chlorine, and trace elements) were determined. Legionella spp. were detected in 33 (22.6%) and Pseudomonas spp. in 56 (38.4%) of 146 samples. Some factors associated with Legionella contamination were heater type, tank distance and capacity, water plant age, and mineral content. Pseudomonas presence was influenced by water source, hardness, free chlorine, and temperature. Legionella contamination was associated with a centralized heater, distance from the heater point >10 m, and a water plant >10 years old. Furthermore, zinc levels of <100 microg/L and copper levels of >50 microg/L appeared to be protective against Legionella colonization [corrected]. Legionella species and serogroups were differently distributed according to heater type, water temperature, and free chlorine, suggesting that Legionella strains may have a different sensibility and resistance to environmental factors and different ecologic niches. PMID:15109413

  6. Design package for solar domestic hot water system

    SciTech Connect

    1980-09-01

    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.

  7. Uranium in US surface, ground, and domestic waters

    SciTech Connect

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

    1981-04-01

    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 concentrations 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.

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

    SciTech Connect

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

    1981-04-01

    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.

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

    SciTech Connect

    S. Mastilovic

    2000-03-02

    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).

  10. Uranium in US surface, ground, and domestic waters

    SciTech Connect

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

    1981-04-01

    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 concentrations 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.

  11. Par Pond Fish, Water, and Sediment Chemistry

    SciTech Connect

    Paller, M.H.; Wike, L.D.

    1996-06-01

    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.

  12. 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

  13. Review of domestic water conservation practices in Saudi Arabia

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

    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.

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

    USGS Publications Warehouse

    Lane, R.C.

    2004-01-01

    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.

  15. Sediment mediated species interactions in coastal waters

    NASA Astrophysics Data System (ADS)

    Reise, Karsten

    2002-10-01

    Self-structuring in marine sediment communities is achieved by the mobility of the organisms, the trophic web, and biogenic transformations of the habitat. The latter are: bioconstruction and bioturbations, sediment stabilisation and destabilisation, with facilitating and inhibiting effects. This cursory overview intends to show that in near-shore mud and sand, biogenic habitat transformations pervade all community interactions. Consequently these deserve as much attention in benthic ecosystem analyses as do trophic pathways. Abundant phototrophs and suspension feeders tend to accumulate sediment and organic matter. Underneath phototrophic mats, composite layers of anaerobic microorganisms abound. Benthic animals provide anchorage to tufts of algae, and these in turn provide shelter and food for mobile benthos. Rooted plants slow down hydrodynamics and generate complex habitats above the sediment surface but below a meshwork of roots may inhibit burrowing animals. Abundant suspension feeders stabilise sediments, and may build loose hummocks, multi-species epibenthic thickets or solid reefs, accommodating diverse epibenthic assemblages. Their raised and rough surfaces enhance turbulence. Below the sediment surface, tubes and burrows of sessile or discretely motile animals provide microoxic habitats for diverse assemblages of small organisms. At the surface, mucus of motile organisms increases sediment cohesion. Accumulated dead hardparts of the benthos support epibionts when at the surface but cause resistance to the burrowers below. Reworking and irrigation of the sediment by the infauna increases oxygenation, and particulate and solute fluxes with the overlying water. Mounds and pits generated by resident burrowers as well as by large visiting grazers and predators further diversify the benthos. All these bioengineered structures and processes generate dynamic and complex habitat-mediated interaction webs, affecting and meshed into the trophic web, which they may rival in overall importance in the self-structuring of the benthos in coastal marine sediments.

  16. Domestic water conservation practices in Tlemcen City (Algeria)

    NASA Astrophysics Data System (ADS)

    Habi, Mohammed; Harrouz, Omar

    2014-03-01

    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.

  17. Patterns, structures and regulations of domestic water cycle systems in China

    NASA Astrophysics Data System (ADS)

    Chu, Junying; Wang, Hao; Wang, Jianhua; Qin, Dayong

    2010-05-01

    Domestic water cycle systems serving as one critical component of artificial water cycle at the catchment's scale, is so closely related to public healthy, human rights and social-economic development, and has gained the highest priority in strategic water resource and municipal infrastructure planning. In this paper, three basic patterns of domestic water cycle systems are identified and analyzed, including rural domestic water system (i.e. primary level), urban domestic water system (i.e. intermediate level) and metropolitan domestic water system (i.e. senior level), with different "abstract-transport-consume-discharge" mechanisms and micro-components of water consumption (such as drinking, cooking, toilet flushing, showering or cleaning). The rural domestic water system is general simple with three basic "abstract-consume-discharge" mechanisms and micro-components of basic water consumption such as drinking, cooking, washing and sanitation. The urban domestic water system has relative complex mechanisms of "abstract-supply-consume-treatment-discharge" and more micro-components of water consumption such as bath, dishwashing or car washing. The metropolitan domestic water system (i.e. senior level) has the most complex mechanisms by considering internal water reuse, external wastewater reclamation, and nutrient recycling processes. The detailed structures for different water cycle pattern are presented from the aspects of water quantity, wastewater quality and nutrients flow. With the speed up of urbanization and development of social-economy in China, those three basic patterns are interacting, transforming and upgrading. According to the past experiences and current situations, urban domestic water system (i.e. intermediate level) is the dominant pattern based on indicator of system number or system scale. The metropolitan domestic water system (i.e. senior level) is the idealized model for the future development and management. Current domestic water system management efforts typically fail in China, because the approach is generally narrowly-focused and fragmented. This paper put forward a total-process control framework following the water and pollutants (or nutrients) flows along the dualistic domestic water cycle process. Five key objectives of domestic water cycle system regulation are identified including water use safety, water use equity, water saving, wastewater reduction and nutrient recycling. Comprehensive regulatory framework regarding administrative, economic, technical and social measures is recommended to promote sustainable domestic water usage and demand management. Considering the relatively low affordability in rural area, economic measures should be mainly applied in urban domestic water systems and metropolitan domestic water systems. Engineering or technological measures which are suitable to the three domestic water cycle systems are discussed respectively.

  18. 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...

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

    PubMed

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

    2014-12-01

    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

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

    PubMed Central

    Bradley, David J.; Bartram, Jamie K.

    2013-01-01

    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

  1. Mycobacterium avium subsp. paratuberculosis in Lake Catchments, in River Water Abstracted for Domestic Use, and in Effluent from Domestic Sewage Treatment Works: Diverse Opportunities for Environmental Cycling and Human Exposure

    PubMed Central

    Pickup, R. W.; Rhodes, G.; Bull, T. J.; Arnott, S.; Sidi-Boumedine, K.; Hurley, M.; Hermon-Taylor, J.

    2006-01-01

    Mycobacterium avium subsp. paratuberculosis from infected animals enters surface waters and rivers in runoff from contaminated pastures. We studied the River Tywi in South Wales, United Kingdom, whose catchment comprises 1,100 km2 containing more than a million dairy and beef cattle and more than 1.3 million sheep. The River Tywi is abstracted for the domestic water supply. Between August 2002 and April 2003, 48 of 70 (68.8%) twice-weekly river water samples tested positive by IS900 PCR. In river water, the organisms were associated with a suspended solid which was depleted by the water treatment process. Disposal of contaminated slurry back onto the land established a cycle of environmental persistence. A concentrate from 100 liters of finished water tested negative, but 1 of 54 domestic cold water tanks tested positive, indicating the potential for these pathogens to access domestic outlets. In the separate English Lake District region, with hills up to 980 m, tests for M. avium subsp. paratuberculosis in the high hill lakes and sediments were usually negative, but streams and sediments became positive lower down the catchment. Sediments from 9 of 10 major lakes receiving inflow from these catchments were positive, with sediment cores indicating deposition over at least 40 to 50 years. Two of 12 monthly 1-liter samples of effluent and a single 100-liter sample from the Ambleside sewage treatment works were positive for M. avium subsp. paratuberculosis. Since Lake Ambleside discharges into Lake Windermere, which is available for domestic supply, there is a potential for these organisms to cycle within human populations. PMID:16751517

  2. CONTAMINATED MARINE SEDIMENTS: WATER COLUMN AND INTERSTITIAL TOXIC EFFECTS

    EPA Science Inventory

    The toxicity that contaminated sediments may introduce into the water column has not been measured extensively. n order to quantify this potential toxicity, the seawater overlying two uncontaminated and three contaminated marine sediments was evaluated in the laboratory with the ...

  3. Numerical Simulation of a Solar Domestic Hot Water System

    NASA Astrophysics Data System (ADS)

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

    2014-11-01

    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.

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

    NASA Technical Reports Server (NTRS)

    Hall, J. B., Jr.

    1973-01-01

    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.

  5. 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...

  6. The lipid geochemistry of interstitial waters of recent marine sediments

    SciTech Connect

    Saliot, A.; Brault, M.; Boussuge, C. )

    1988-04-01

    To elucidate the nature of biogeochemical processes occurring at the water-sediment interface, the authors have analyzed fatty acids, n-alkanes and sterols contained in interstitial waters collected from oxic and anoxic marine sediments in the eastern and western intertropical Atlantic Ocean and in the Arabian Sea. Lipid concentrations in interstitial waters vary widely and are generally much higher than concentrations encountered in the overlying sea water. Higher concentrations in interstitial water are observed in environments favorable for organic input and preservation of the organic matter in the water column and in the surficial sediment. The analysis of biogeochemical markers in the various media of occurrence of the organic matter such as sea water, suspended particles, settling particles and sediment is discussed in terms of differences existing between these media and bio-transformations of the organic matter at the water-sediment interface.

  7. Effect of sediments on the survival of Escherichia coli in marine waters.

    PubMed Central

    Gerba, C P; McLeod, J S

    1976-01-01

    Escherichia coli, a fecal coliform, was found to survive for longer periods of time in unsterile natural seawater when sediment material was present than in seawater alone, and at least on one occasion growth was observed to occur. This enteric bacterium was found to increase rapidly in number in autoclaved natural seawater and autoclaved sediment taken from areas receiving domestic wastes, even when the seawater had salinities as high as 34 g/kg. However, in autoclaved seawater, growth was always more gradual and never reached numbers as high as those observed when sediment was present. It was found that nutrients were easily eluted from the sediment after autoclaving or upon addition to artificial seawater, but little elution occured during mixing of the sediments with unsterile natural seawater. The longer survival of E. coli in the sediment is attributed to the greater content of organic matter present in the sediment than the sweater. These laboratory results, in part, could explain why on a volume basis larger numbers of coliforms and fecal coliforms and fecal coliforms were found in estuarine sediments than the overlaying water at field sites. PMID:788634

  8. 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 ...

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

    NASA Technical Reports Server (NTRS)

    Hall, J. B., Jr.

    1973-01-01

    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.

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

    SciTech Connect

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

    2012-07-01

    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.

  11. Benthic invertebrate bioassays with toxic sediment and pore water

    USGS Publications Warehouse

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

    1990-01-01

    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.

  12. Quantification of sediment-water interactions in a polluted tropical river through biogeochemical modeling

    NASA Astrophysics Data System (ADS)

    Trinh, Anh Duc; Meysman, Filip; Rochelle-Newall, Emma; Bonnet, Marie Paule

    2012-09-01

    Diagenetic modeling presents an interesting and robust way to understand sediment-water column processes. Here we present the application of such a model to the Day River in Northern Vietnam, a system that is subject to high levels of domestic wastewater inputs from the Hanoi metropolitan area. Experimental data from three areas of different water and sediment quality, combined with some additional data from the river, are used to set up and calibrate a diagenetic model. The model was used to determine the role of the sediments as a sink for carbon and nutrients and shows that in the dry season, 27% of nitrogen, 25% of carbon, and 38% of phosphorus inputs into the river system are stored in sediments. The corresponding numbers during the rainy season are 15%, 10%, and 20%, respectively. The diagenetic model was then used to test the impact of an improvement in the treatment of Hanoi's municipal wastewater. We show that improved wastewater treatment could reduce by about 17.5% the load of organic matter to the sediment. These results are the first to highlight the importance of sediments as a potential removal mechanism of organic matter and nutrients from the water column in this type of highly impacted tropical urban river, further demonstrating that rivers need to be considered as reaction sites and not just as inert conduits.

  13. Promising freeze protection alternatives in solar domestic hot water systems

    SciTech Connect

    Bradley, D.E.

    1997-12-31

    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.

  14. Suspending sediment transport, sedimentation, and resuspension in Lake Houston, Texas: Implications for water quality

    SciTech Connect

    Matty, J.M.; Anderson, J.B.; Dunbar, R.B. )

    1987-01-01

    Lake Houston is a man-made reservoir located northeast of Houston, Texas. The purpose of this investigation was to document suspended sediment transport, sedimentation, and resuspension in the lake with a view towards estimating the influence of sedimentation on water quality. Sediment traps were placed in strategic locations in the lake to collect suspended sediments. Samples were analyzed for bulk density, grain size, organic carbon, and a number of trace elements. These data were analyzed along with meteorological data to examine those factors which regulate suspended sediment input and dispersal, and the role of suspended sediments in controlling water quality within the lake. Sediment input to the lake depends primarily on the intensity of rainfall in the watershed. Sediment movement within the lake is strongly influenced by wave activity, which resuspends sediments from shallow areas, and by wind-driven circulation. The increased residence time of suspended sediments due to resuspension allows greater decomposition of organic matter and the release of several trace elements from sediments to the water column. Virtually all samples from sediment traps suspended between 1 and 5 m above the lake bottom contain medium to coarse silt, and even some very fine sand-sized material. This implies that circulation in Lake Houston is periodically intense enough to transport this size material in suspension. During winter, northerly winds with sustained velocities of greater than 5 m/sec provide the most suitable condition for rapid (< 1 d) transport of suspended sediment down the length of the lake. Fluctuations in current velocities and the subsequent suspension/deposition of particles may explain variations in the abundance of coliform bacteria in Lake Houston.

  15. DEVELOPING WATER QUALITY CRITERIA FOR SUSPENDED AND BEDDED SEDIMENTS

    EPA Science Inventory

    The U.S. EPAs 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...

  16. Mathematical Simulation of Sediment and Radionuclide Transport in Surface Waters

    SciTech Connect

    ,

    1981-04-01

    The study objective of "The Mathematical Simulation of Sediment and Radionuclide Transport in Surface Waters" is to synthesize and test radionuclide transport models capable of realistically assessing radionuclide transport in various types of surface water bodies by including the sediment-radionuclide interactions. These interactions include radionuclide adsorption by sediment; desorption from sediment into water; and transport, deposition, and resuspension of sorbed radionuclides controlled by the sediment movements. During FY-1979, the modification of sediment and contaminant (radionuclide) transport model, FETRA, was completed to make it applicable to coastal waters. The model is an unsteady, two-dimensional (longitudinal and lateral) model that consists of three submodels (for sediment, dissolved-contaminant, and particulate-contaminant transport), coupled to include the sediment-contaminant interactions. In estuaries, flow phenomena and consequent sediment and radionuclide migration are often three-dimensional in nature mainly because of nonuniform channel cross-sections, salinity intrusion, and lateral-flow circulation. Thus, an unsteady, three-dimensional radionuclide transport model for estuaries is also being synthesized by combining and modifying a PNL unsteady hydrothermal model and FETRA. These two radionuclide transport models for coastal waters and estuaries will be applied to actual sites to examine the validity of the codes.

  17. Assessment of heavy metal concentration in the Khoshk River water and sediment, Shiraz, Southwest Iran.

    PubMed

    Salati, S; Moore, F

    2010-05-01

    Heavy metal contents and contamination characteristics of the water and sediment of the Khoshk River, Shiraz, Southwest Iran were investigated. The abundance of heavy metals decreases as Zn > Mn > Cr > Ni >Pb > Cu > Cd in water samples and Mn > Cr > Pb > Ni > Zn > Cu > Cd in sediments, respectively. Based on the enrichment factor and geoaccumulation index values, sediments were loaded with Cr, Zn, Pb, Cu, and Cd. Pearson correlation matrix as well as cluster and principal components analyses and analysis of variance were implemented on data from sampling sites. Based on the locations of sampling sites in clusters and variable concentrations at these stations, it was concluded that municipal, industrial, and domestic discharges in the Shiraz urban area strongly affected heavy metals concentrations in the Khoshk River water and sediment. Results obtained from principal components analysis of sediment samples showed that the high concentration of Ni was mainly from natural origin, related to the composition of parent rocks, while the elevated values of Cr, Zn, Pb, Cd, and Cu were due to anthropogenic activities. PMID:19421887

  18. Degassing of pore water methane during sediment incubations

    SciTech Connect

    Kiene, R.P.; Capone, D.G.

    1985-01-01

    Laboratory experiments were used to examine the degassing of CH/sub 4/ from a muddy sediment. Sediment containing dissolved CH/sub 4/ showed a hyperbolic time course of CH/sub 4/ release when allowed to degas in stoppered 20-ml vials. Equilibration required ca. 24 h for 5 ml of sediment. The rate of CH/sub 4/ release was found to be dependent on the ratio of exposed sediment surface area to sediment volume. The water content of the sediment was a factor in the total amount of CH/sub 4/ released but did not affect the rate of degassing. Addition of water to sediment samples (to form a slurry) accelerated CH/sub 4/ release, with a 1:1 dilution giving ca. 80% of maximum release after only 2 min. Shaking the sediments also facilitated CH/sub 4/ exchange, with 2 min of vigorous agitation giving 77% of maximum release. The organic content of the sediment did not affect either the amount or the rate of CH/sub 4/ degassing. Rubber stoppers exposed to CH/sub 4/ were found to absorb CH/sub 4/ rapidly and to subsequently release it in proportion to the concentration to which they were exposed. Artifacts may be associated with CH/sub 4/ production measurements if sediment and stopper degassing are not considered. It is recommended that any study of methane production or distribution include preliminary experiments to determine the degassing kinetics for the specific sediment system being used.

  19. Degassing of Pore Water Methane during Sediment Incubations.

    PubMed

    Kiene, R P; Capone, D G

    1985-01-01

    Laboratory experiments were used to examine the degassing of CH(4) from a muddy sediment. Sediment containing dissolved CH(4) showed a hyperbolic time course of CH(4) release when allowed to degas in stoppered 20-ml vials. Equilibration required ca. 24 h for 5 ml of sediment. The rate of CH(4) release was found to be dependent on the ratio of exposed sediment surface area to sediment volume. The water content of the sediment was a factor in the total amount of CH(4) released but did not affect the rate of degassing. Addition of water to sediment samples (to form a slurry) accelerated CH(4) release, with a 1:1 dilution giving ca. 80% of maximum release after only 2 min. Shaking (vortexing) the sediments also facilitated CH(4) exchange, with 2 min of vigorous agitation giving 77% of maximum release. The organic content of the sediment did not affect either the amount or the rate of CH(4) degassing. Rubber stoppers exposed to CH(4) were found to absorb CH(4) rapidly and to subsequently release it in proportion to the concentration to which they were exposed. Artifacts may be associated with CH(4) production measurements if sediment and stopper degassing are not considered. It is recommended that any study of methane production or distribution include preliminary experiments to determine the degassing kinetics for the specific sediment system being used. PMID:16346693

  20. Degassing of Pore Water Methane during Sediment Incubations

    PubMed Central

    Kiene, Ronald P.; Capone, Douglas G.

    1985-01-01

    Laboratory experiments were used to examine the degassing of CH4 from a muddy sediment. Sediment containing dissolved CH4 showed a hyperbolic time course of CH4 release when allowed to degas in stoppered 20-ml vials. Equilibration required ca. 24 h for 5 ml of sediment. The rate of CH4 release was found to be dependent on the ratio of exposed sediment surface area to sediment volume. The water content of the sediment was a factor in the total amount of CH4 released but did not affect the rate of degassing. Addition of water to sediment samples (to form a slurry) accelerated CH4 release, with a 1:1 dilution giving ca. 80% of maximum release after only 2 min. Shaking (vortexing) the sediments also facilitated CH4 exchange, with 2 min of vigorous agitation giving 77% of maximum release. The organic content of the sediment did not affect either the amount or the rate of CH4 degassing. Rubber stoppers exposed to CH4 were found to absorb CH4 rapidly and to subsequently release it in proportion to the concentration to which they were exposed. Artifacts may be associated with CH4 production measurements if sediment and stopper degassing are not considered. It is recommended that any study of methane production or distribution include preliminary experiments to determine the degassing kinetics for the specific sediment system being used. PMID:16346693

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

    PubMed

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

    2014-01-01

    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

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

    NASA Technical Reports Server (NTRS)

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

    1974-01-01

    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.

  3. Measurement of Mercury Methylation in Lake Water and Sediment Samples

    PubMed Central

    Furutani, Akira; Rudd, John W. M.

    1980-01-01

    Biological mercury methylation was assayed by a new radiochemical technique in the water column and sediments of a mercury-contaminated lake. In 24 weeks during 1979, there were three episodes of methylating activity in surface floc and in water, each lasting 3 to 5 weeks. Periods of methylation in the water column coincided with surface sediment methylation and appeared to be related to overall microbial activity. Mercury was actively methylated in the presence of bound sulfide. PMID:16345649

  4. Building America Top Innovations 2012: Model Simulating Real Domestic Hot Water Use

    SciTech Connect

    none,

    2013-01-01

    This Building America Top Innovations profile describes Building America research that is improving domestic hot water modeling capabilities to more effectively address one of the largest energy uses in residential buildings.

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

    PubMed Central

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

    2011-01-01

    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

  6. 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...

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

    USGS Publications Warehouse

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

    2011-01-01

    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.

  8. 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 ...

  9. Methylantimony and -arsenic species in sediment pore water tested with the sediment or fauna incubation experiment.

    PubMed

    Duester, Lars; Vink, Jos P M; Hirner, Alfred V

    2008-08-15

    In this study, the speciation of arsenic (As) and antimony (Sb) across a water-sediment interface and the formation of mono-, di-, and trimethylated species overtime in a microfiltered pore water solution were examined. We used an experimental technique, known as the sediment or fauna incubation experiment (SOFIE), which enables the determination of chemical speciation across redox zones in undisturbed systems. Five different incubation experiments were run: Over a 76 day incubation period, pore water was sampled and speciated 5 times. These experiments revealed the complete methylated species pattern for arsenic and antimony in the microfiltered sediment pore water. This constitutes the first report of methylated As and Sb species in a true pore water solution of sediments. Predominant organic species were dimethylantimony (DMSb up to 2.7 microg/L) and dimethylarsenic (DMAs up to 4.3 microg/L) followed by monomethylated species (MMAs and MMSb). These data (i) indicate that methylation significantly influences the translocation of As and Sb in sediments, (ii) demonstrate good agreement between the occurrence of methylantimony and the occurrence of methylarsenic in the pore water, (iii) reveal that As transformation in sediments is faster than Sb transformation but is more susceptible to disturbances from acidification, and (iv) regarding the translocation of these elements and antimony in particular, methylation is clearly a relevant, and perhaps as yet underestimated, factor. PMID:18767637

  10. Physicomechanical properties of the water-sediment barrier zone

    NASA Astrophysics Data System (ADS)

    Ivanov, G. I.; Svertilov, A. A.; Kholmyanskii, M. A.

    2012-11-01

    The complex geoecological works carried out in the St. Anna Trough resulted in the detailed investigation of the water-sediment barrier zone. The physicomechanical properties such as the moisture, the moisture at the flowing boundary, the sedimentation rates, and the strength of the sediments measured and calculated for the upper 10-cm-thick layer of the bottom sediments were used as the main parameters characterizing the barrier zone. These data served as a basis for developing the model of the barrier zone with defining the lithogenesis stages: protosyngenesis—syngenesis—protodiagenegis—early diagenesis. The quantitative estimates of the environmental physicochemical properties presented in this work characterize each of these stages.

  11. Impact of storm-water outfalls on sediment quality in Corpus Christi Bay, Texas, USA

    SciTech Connect

    Carr, R.S.; Montagna, P.A.; Biedenbach, J.M.; Kalke, R.; Kennicutt, M.C.; Hooten, R.; Cripe, G.

    2000-03-01

    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., industrial and domestic outfalls, oil field-produced water discharges, and dredging activity) and eight reference sites were also evaluated. Sediment samples were collected and analyzed for physical-chemical characteristics, contaminant concentrations (metals, polycyclic aromatic hydrocarbons [PAHs], polychlorinated biphenyls [PCBs], and pesticides), toxicity, and a benthic index of biotic integrity (BIBI) composed of 10 independent metrics calculated for each site. This large data matrix was reduced using multivariate analysis to create new variables for each component representing overall means and containing most of the variance in the larger data set. The new variables were used to conduct the correlation analysis. Toxicity was significantly correlated with both chemistry and ecological responses, whereas no correlations between the benthic metrics and sediment chemistry were observed. Using the combined information from the SQT, four of the five most degraded sites were storm-water outfall sites. Although estuaries are naturally stressful environments because of salinity and temperature fluctuations, this ecosystem appears to have been compromised by anthropogenic influences similar to what has been observed for other heavily urbanized bay systems along the Texas and Gulf coast.

  12. Water recovery and solid waste processing for aerospace and domestic applications

    NASA Technical Reports Server (NTRS)

    Murawczyk, C.

    1973-01-01

    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.

  13. Sediment Transport and Water Quality Model of Cedar Lake, Indiana

    NASA Astrophysics Data System (ADS)

    James, S. C.; Jones, C. A.; Roberts, J. D.; Ahlmann, M.; Bucaro, D. A.

    2006-12-01

    The EPA-supported Environmental Fluid Dynamics Code, EFDC, is used to model hydrodynamics, sediment transport, and water quality in coastal regions, estuaries, rivers, and lakes. However, the empirical formulations used for sediment transport are not always adequate to accurately characterize cohesive sediment erosion and transport. New sediment transport subroutines have been incorporated into EFDC and the new model is called SNL-EFDC. The updated model provides an improved, coupled hydrodynamics, sediment transport, and water quality framework. The newly incorporated sediment transport subroutines facilitate direct use of measured erosion rate data from the Sediment Erosion with Depth Flume (SEDflume). Erosion rates are included as functions of both depth within the sediment bed and applied shear stresses. This bypasses problems associated with empirical erosion formulations often based on disaggregated particle size. Restoration alternatives are under consideration for Cedar Lake in Indiana and SNL-EFDC models its hydrodynamics, sediment transport, and water quality. The water quality model as implemented on Cedar Lake tracks algae, oxygen, temperature, carbon, phosphorous, and nitrogen kinetics, as well as, sediment bed diagenesis. Environmental conditions, wind, temperature, rainfall, and sunlight, were based on data collected in 2005. Tributary loading was modeled using L-THIA and provided influxes of water, nutrients (phosphorous, nitrogen, etc.), and sediments. The calibrated model was used to simulate a nine month period from March to November 2005. Results suggest that the model simulates sediments transport and associated water quality correctly. The calibrated model is being used to evaluate several restoration measures throughout the lake and watershed and their effect on water quality. Because Cedar Lake is a nitrogen limited lake, changes in the level of eutrophication from each measure are being tracked by calculating the Carlson trophic state index based on total phosphorus. To date, several dredging measures have been modeled and the measure resulting in the greatest benefit to water quality per unit dredge volume was identified. Several other restoration measures including nutrient inactivation, increasing dilution, creation of in-lake structures, aquatic vegetation restoration, institutional controls, fish community management, and reducing tributary loadings are currently being modeled and evaluated. As part of the Cedar Lake Ecosystem Restoration Feasibility Study currently being developed by the Chicago District of the U.S. Army Corps of Engineers, results from the EFDC-SNL model will be used to justify a recommended ecosystem restoration plan for implementation. Sandia National Laboratories is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE AC04 94AL85000.

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

    PubMed

    Factori, R; Leles, S M; Novakowski, G C; Rocha, C L S C; Thomaz, S M

    2014-11-01

    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 Pirap River, in Maring, Paran 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

  15. Mid frequency shallow water fine-grained sediment attenuation measurements.

    PubMed

    Holland, Charles W; Dosso, Stan E

    2013-07-01

    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

  16. Effects of exteriorization of the ureters on the water metabolism of the domestic fowl

    PubMed Central

    Dicker, S. E.; Haslam, J.

    1972-01-01

    1. Six domestic fowls were operated for exteriorization of the ureters. 2. Three weeks after the operation their food and water intake was compared with that of six unoperated control fowls of similar weight. 3. Water intake was calculated from the amount of water drunk, the metabolic water and the water content of the food eaten; while water loss was estimated from the water content of urine and faeces excreted and from evaporation. 4. Fowls with exteriorized ureters drank more than the control birds. The excess of water drunk by these birds approximated the amount of water lost in the urine. PMID:5071927

  17. Tidally forced asymmetric pore water flow in intertidal coastal sediments

    NASA Astrophysics Data System (ADS)

    Riedel, T.; Lettmann, K.; Beck, M.; Badewin, T.; Brumsack, H. J.

    2009-04-01

    Pore water exchange in shallow intertidal sediments is enhanced by tidally driven advective flow. This flow is a result of the asymmetric pressure distribution within the aquifer sediments during low tide. Accurate quantification is challenging in these systems because of the highly dynamic response of the pore waters to the ever changing hydraulic gradients generated by the tidal gauge. We therefore measured the pressure distribution along a tidal flat margin where pressure gradients are expected to be highest using direct-burial pressure transducers. A hydraulic numerical simulation of the tidal flat margin was set up that was capable of reproducing the pressure distribution within the sediment. The results show that pore waters directly discharge into the coastal waters during low tide releasing the complete pore water inventory of dissolved degradation products, trace metals and radium. The flux of mineralized carbon and nutrients out of the sediment is therefore much faster than in diffusion dominated open-marine systems. The flow also generates asymmetric patterns in pore water chemistry, such as strong increases in dissolved degradation products (dissolved inorganic carbon (DIC), ammonia or silica) with pore water age resulting from microbial degradation of organic matter. Pore water discharge amounts to 250 to 360 l per meter shore line per tide releasing, for example, between 24 to 34 moles of DIC each day. This process of pore water circulation in intertidal sediments is recognized as "biofiltration" of seawater, where redox sensitive species (Mo, U, Re) are trapped within the sediment and mobile pore water constituents mostly released from microbial degradation of organic matter are directly transported into the open waters.

  18. Pore Water Transport of Enterococci out of Beach Sediments

    PubMed Central

    Phillips, Matthew C.; Solo-Gabriele, Helena M.; Reniers, Adrianus J. H. M.; Wang, John D.; Kiger, Russell T.; Abdel-Mottaleb, Noha

    2011-01-01

    Enterococci are used to evaluate the safety of beach waters and studies have identified beach sands as a source of these bacteria. In order to study and quantify the release of microbes from beach sediments, flow column systems were built to evaluate flow of pore water out of beach sediments. Results show a peak in enterococci (average of 10% of the total microbes in core) released from the sand core within one pore water volume followed by a marked decline to below detection. These results indicate that few enterococci are easily removed and that factors other than simple pore water flow control the release of the majority of enterococci within beach sediments. A significantly larger quantity and release of enterococci were observed in cores collected after a significant rain event suggesting the influx of fresh water can alter the release pattern as compared to cores with no antecedent rainfall. PMID:21945015

  19. Effects of a nearshore wastewater discharge: Water column and sediment pore water toxicity

    SciTech Connect

    Krause, P.R.; Carr, R.S.

    1995-12-31

    The relationship between water column and sediment pore water toxicity was investigated near a municipal-industrial wastewater discharge in southern Texas. Toxicity associated with effluent distributions in the water column are known to vary in both time and space. Toxicity of sediment, however, is often more stable over time. Sediment can serve as a long-term integrator of toxicity in areas subject to chronic exposure of effluents. This study addressed the relationship between water column toxicity and that found in the sediments on both spatial and temporal scales. Four 2 Km transacts were established around a nearshore wastewater outfall. Eight stations along each transact were sampled for both surface waters and sediment pore water toxicity. Toxicity was determined using a modified sea urchin fertilization test. Surface waters were sampled and tested for eight consecutive months, while sediment pore waters were sampled on three occasions over the length of this study. Results have shown that toxicity in receiving waters was a good indicator to trace movements of the highly variable effluent plume. The distribution of effluent in the water column, and hence water column toxicity, was primarily driven by local wind conditions. Toxicity in sediment porewater was, much less variable and more evenly distributed over the study site. Sediment pore water toxicity was also a good predictor of the distribution of benthic infaunal invertebrates over much of the study site.

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

    SciTech Connect

    Rudd, A.

    2012-08-01

    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.

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

    SciTech Connect

    Rudd, Armin

    2012-08-01

    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.

  2. Development of Standardized Domestic Hot Water Event Schedules for Residential Buildings

    SciTech Connect

    Hendron, R.; Burch, J.

    2008-08-01

    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.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    On rangelands, free-ranging or loosely-herded domestic sheep tend not to linger in shrub-dominated riparian areas thus limiting their impacts on stream water quality. The water quality effects when sheep are tightly-herded during stream crossings, however, are largely unknown. In this study, downs...

  4. Water and suspended sediment division at a stratified tidal junction

    NASA Astrophysics Data System (ADS)

    Buschman, F. A.; Vegt, M.; Hoitink, A. J. F.; Hoekstra, P.

    2013-03-01

    Tidal junctions play a crucial role in the transport of water, salt, and sediment through a delta distributary network. Water, salt and sediment are exchanged at tidal junctions, thereby influencing the transports in the connecting branches and the overall dynamics of the system. This paper presents observations of water, salt and sediment transports in three channels that connect at a stratified tidal junction. Flow variation in one channel was found to lag behind flow variation in a connected channel by more than 1 h, which is largely attributed to channel length differences from the junction to the sea. The water columns in the three channels were periodically stratified during spring tide, whereas the salinity structure represented a salt wedge during neap tide. Salinity differences between the three channels were substantial. The channels contain water bodies of different salinity and act largely independently. Flow velocities in the upper and lower layers differed substantially. Flow in the lower layer was generally in the direction of acceleration produced by the baroclinic pressure gradient. Interestingly, baroclinic pressure gradients were sometimes directed landward, indicating the presence of saltier water at the land side of the estuary. In sharp channel bends close to the junction, secondary flow was strongest at the highest axial flow velocity during spring tide. In one channel bend, these circulations steered the suspended sediment toward the inner bend, which affected the suspended sediment division.

  5. Sediment tracers in water erosion studies: Current approaches and challenges

    NASA Astrophysics Data System (ADS)

    Guzmn, Gema; Quinton, John N.; Nearing, Mark A.; Mabit, Lionel; Girldez, Juan V.; Gmez, Jos A.

    2013-04-01

    The quest for alternative methods of soil losses assessment, due to water erosion to complement and enhance existing methods has directed attention to the use of tracing approaches because of the additional information they provide, such as sediment source identification, tracking of sediment movement across the landscape at various temporal and spatial scales and soil erosion rates. For these reasons, the utility and robustness of sediment tracing approaches using a wide range of substances and soil properties have been evaluated in numerous studies. A comprehensive literature review on tracing approaches used in water erosion studies was carried out in June 2011 using the Web of Science database and as search terms in the title or as keywords: "erosion AND tracer" OR "sediment AND tracer" OR "sediment AND tracking". The search excluded reviews and tillage and/or wind erosion studies. Only studies that used tracers to make a determination of water erosion or sedimentation rates, or in some cases relative erosion contribution, were considered in this study, and were further refined by manually checking that the articles corresponded to experiments involving sediment studies using tracers, as defined within the context of this review. Five distinct groups of tracing approaches were identified: fallout radionuclides, rare earth elements, soil magnetism and magnetic substances, other tracers, and sediment fingerprinting techniques. This abstract presents a synthesis of the current approaches of each of the tracing techniques identified in assessing soil erosion and sediment redistribution and a summary with the commonalities and differences between the approaches and identifying research gaps and future trends.

  6. Acute toxicity screening of reservoir water and sediment

    SciTech Connect

    Moses, J.; Wade, D.C.

    1991-05-01

    Toxicological evaluation of forebay and transition area water column (overlying water) and sediment porewater (interstitial water) samples was initiated during the summer of 1990 as part of TVA's Reservoir Vital Signs monitoring. Twenty-four stations were identified for study using acute toxicity screening test methods with the freshwater rotifer Brachionus calyciflorus (Rotox{reg sign}) and light emitting bacteria Photobacterium phosphoreum (Microtox{reg sign}). No acute toxicity to rotifers was demonstrated in the first series of tests using water column and sediment samples from the locations selected for monitoring. Sediments from three locations indicated some toxicity based on Microtox{reg sign}, although all EC{sub 50} concentrations were greater than 100 percent sample.

  7. Assessing and managing sediment contamination in transitional waters.

    PubMed

    Chapman, Peter M; Wang, Feiyue; Caeiro, Sandra Sofia

    2013-05-01

    Sediment contamination remains a global problem, particularly in transitional waters such as estuaries and coastal lagoons, which are the recipients of chemicals from multiple near- and far-field sources. Although transitional waters are highly productive ecosystems, approaches for assessing and managing their sediment contamination are not as well developed as in marine and fresh waters. Further, although transitional waters remain defined by their variable and unique natural water quality characteristics, particularly salinity, the biota inhabiting such ecosystems, once thought to be defined by Remane's "paradox of brackish water", are being redefined. The purpose of the present paper is to build on an earlier but now dated (>12years old) review of methods to assess sediment contamination in estuaries, extending this to all transitional waters, including information on integrative assessments and on management decision-making. The following are specifically discussed: chemical assessments; bioindicators; biomarkers; and, biological surveys. Assessment and management of sediment contamination in transitional waters need to be focused on ecosystem services and, where appropriate and possible, be proactive rather than reactive when uncertainty has been suitably reduced. PMID:23528483

  8. Simulation of a DHW system with a vacuum collector using TRNSYS[Domestic Hot Water

    SciTech Connect

    Li, Xiaoping; Saito, Teruyuki; Okumiya, Masaya; Yoshinaga, Mika

    1999-07-01

    Simulation of a solar domestic water heating system was carried out using TRNSTS. To apply the program to a system including a vacuum-pipes collector whose model is not provided in TRNSYS, a modification of collector was adopted. By comparing the predicted values to measured values, the validity of the simulation program and the modification are certified. And also, annual simulations of two kinds of solar domestic water heating systems with two standard meteorological data were carried out. Through the simulation results some knowledge of standard meteorological data were obtained. Also, their influence to various systems with different collectors (here flat-plate collector and vacuum-pipes collector) were discussed.

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

    SciTech Connect

    Not Available

    1980-05-01

    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.

  10. Comparison of six generic solar domestic hot water systems

    SciTech Connect

    Farrington, R.B.; Murphy, L.M.; Noreen, D.L.

    1980-04-01

    The cost effectiveness of residential solar water heating is explored by analyzing six different system types. A figure of merit (that considers both performance and cost) is calculated for each system, providing information for both researchers and industry. Thermosyphon water heaters are determined to be the most cost effective option, and their wider application is recommended once a reliable draindown technique is developed.

  11. Preliminary design package for Sunspot Domestic Hot Water Heating System

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The design review includes a drawing list, auto-control logic, measurement definitions, and other document pertaining to the 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 site data acquisition.

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

    NASA Astrophysics Data System (ADS)

    Machingambi, Memory; Manzungu, Emmanuel

    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.

  13. Opportunities for utility involvement with solar domestic hot water

    SciTech Connect

    Carlisle, N.; Christensen, C. ); Barrett, L. )

    1992-05-01

    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 options, and long-term maintenance arrangements. This paper covers three topics: (1) the energy and demand impacts of solar water heating on utility load profiles based on the results of four studies in the literature, (2) the results of workshops sponsored by the National Renewable Energy Laboratory (NREL) to identify key issues faced by utilities in considering residential solar water heating as a DSM option, (3) several current or planned utility programs to promote solar water heating. 7 refs.

  14. Response of crayfish to hyporheic water availability and excess sedimentation

    USGS Publications Warehouse

    Dyer, Joseph J.; Worthington, Thomas A.; Brewer, Shannon K.

    2015-01-01

    Crayfish in many headwater streams regularly cope with seasonal drought. However, it is unclear how landscape changes affect the long-term persistence of crayfish populations. We designed two laboratory experiments to investigate the acute effects of common landscape stressors on crayfish: water withdrawal and sedimentation. The first experiment tested the interaction among water withdrawals (four 24-h water reductions of 0, 15, 30, or 45cm) and two substrate treatments (pebble and cobble) on the burrowing depth of crayfish. The second experiment evaluated the effects of excess fine sediment (three treatments of 0, 45, and 90% sediment) and substrate type (cobble and pebble) on crayfish burrowing depth. Crayfish were able to burrow deeper into the simulated hyporheic zone in cobble substrate when compared to pebble. Crayfish subjected to greater water withdrawals in the pebble treatment were not able to reach the simulated hyporheic zone. Excess fine sediment reduced the depth that crayfish burrowed, regardless of substrate type. Results from this study suggest excess fine sediment may reduce crayfish persistence, particularly when seeking refuge during prolonged dry conditions.

  15. Spectroscopic analyses of pollutants in water, sediment and fish

    NASA Astrophysics Data System (ADS)

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

    2012-11-01

    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.

  16. Presence of Thermophilic Bacteria in Laundry and Domestic Hot-Water Heaters

    PubMed Central

    Brock, Thomas D.; Boylen, Kathryn L.

    1973-01-01

    Thermophilic bacteria resembling Thermus aquaticus were isolated from hot water taken from domestic and commercial hot-water tanks. Cold water from the same locations never yielded thermophilic bacteria, suggesting that the bacteria were growing in the tanks. In contrast to the T. aquaticus isolates from hot springs, the present isolates were rarely pigmented. In general, the hotter sources more frequently yielded bacteria. PMID:4568892

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

    NASA Technical Reports Server (NTRS)

    Murray, R. W.

    1973-01-01

    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.

  18. Seasonal variations in pore water and sediment geochemistry of littoral lake sediments (Asylum Lake, MI, USA)

    PubMed Central

    Koretsky, Carla M; Haas, Johnson R; Miller, Douglas; Ndenga, Noah T

    2006-01-01

    Background Seasonal changes in pore water and sediment redox geochemistry have been observed in many near-surface sediments. Such changes have the potential to strongly influence trace metal distribution and thus create seasonal fluctuations in metal mobility and bioavailability. Results Seasonal trends in pore water and sediment geochemistry are assessed in the upper 50 cm of littoral kettle lake sediments. Pore waters are always redox stratified, with the least compressed redox stratification observed during fall and the most compressed redox stratification observed during summer. A 2-step sequential sediment extraction yields much more Fe in the first step, targeted at amorphous Fe(III) (hydr)oxides (AEF), then in the second step, which targets Fe(II) monosulfides. Fe extracted in the second step is relatively invariant with depth or season. In contrast, AEF decreases with sediment depth, and is seasonally variable, in agreement with changes in redox stratification inferred from pore water profiles. A 5-step Tessier extraction scheme was used to assess metal association with operationally-defined exchangeable, carbonate, iron and manganese oxide (FMO), organic/sulfide and microwave-digestible residual fractions in cores collected during winter and spring. Distribution of metals in these two seasons is similar. Co, As, Cd, and U concentrations approach detection limits. Fe, Cu and Pb are mostly associated with the organics/sulfides fraction. Cr and Zn are mostly associated with FMO. Mn is primarily associated with carbonates, and Co is nearly equally distributed between the FMO and organics/sulfide fractions. Conclusion This study clearly demonstrates that near-surface lake sediment pore water redox stratification and associated solid phase geochemistry vary significantly with season. This has important ramifications for seasonal changes in the bioavailability and mobility of trace elements. Without rate measurements, it is not possible to quantify the contribution of various processes to natural organic matter degradation. However, the pore water and solid phase data suggest that iron reduction and sulfate reduction are the dominant pathways in the upper 50 cm of these sediments. PMID:17181862

  19. Domestic water treatment appliances and the fluoride ion.

    PubMed

    Robinson, S N; Davies, E H; Williams, B

    Specific ion metering of fluoride ion levels of water samples obtained after passage through water softeners and a conditioner showed no alteration in concentration when compared with controls. Similar comparison of water samples passed through water filters demonstrated that highly significant amounts of fluoride ion were removed. In one filter tested, 90% of the fluoride content was lost in the filtration process. The findings of this study suggest that, in a household using a filter, it may be necessary to increase the fluoride supplement or in some cases to initiate use of fluoride supplements as children are not receiving as much fluoride as was thought. New guidelines are required to take account of this surprising effect. PMID:1888589

  20. [Research of urban eutrophic water repair by water/sediment biological bases].

    PubMed

    Zhou, Hui-Hua; Song, Xiao-Guang; Wu, Ge; Xie, Xin-Yuan

    2013-10-01

    A micro power turbine water aeration system with a water biological base and a sediment biological base was independently developed, aimed at urban water eutrophication. The results showed that the average removal rates of COD, NH+4 -N, TP by the water biological base were 82. 33% , 98. 00% and 54. 73% , respectively; The sediment reduction rate achieved by the sediment biological base could reach 20% within 5 days, and aeration in the overlying water could relieve the nutrient releasing caused by the degradation of organic matter; The effect of nutrient removal and organic matter reduction in sediment by the combined ecological restoration technology was perfect in pilot scale. The average removal rates of COD, NH+4 -N, TP were 52. 0%, 33. 6% and 23.4%, respectively, and the organic content in sediment was reduced from 38. 20% to 12.20% . PMID:24364306

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

    USGS Publications Warehouse

    Steele, E.K.

    1985-01-01

    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)

  2. Tributary Sediment Yield, Water Yield and Sediment Composition as Controls of Habitat Heterogeneity in River Networks

    NASA Astrophysics Data System (ADS)

    Rice, S.; Ferguson, R.; Hoey, T.

    2005-05-01

    There is growing evidence that the delivery of water and sediment from tributaries can, via changes in habitat, elicit biological responses in the recipient channel. In particular, greater habitat heterogeneity near confluences may support biodiversity "hotspots" of broad, ecosystem significance. However, our understanding of what controls tributary impacts is very limited. This hinders effective consideration of confluences in river management practice; a problem that is pressing because of recognition that lotic ecosystems involve bio-physical interactions across networks, rather than along simple drainage lines. To date, field data have been used to specify empirical rules relating the probability of a tributary's impact to basin properties such as relative area. This approach has the advantage that it is easily applied at landscape scales, but because basin characteristics are used as gross surrogates for sediment flux, water flux, and sediment composition, little has been learned about the operation and interaction of these primary controls. We therefore used a 1-D sediment routing model with multiple grain-size fractions to investigate mainstream responses to inputs of water and sediment at confluences. Simulations were performed for different initial conditions, using many combinations of values of three independent parameters: the ratios of tributary to mainstream water flux (QR), sediment flux (FR) and characteristic bed load grain size (DR). A primary distinction can be made between confluences that exhibit aggradation (DR > 2) and those that exhibit degradation (DR < 1 or FR = 0), but in the real world post-confluence degradation is rare and we therefore focus here on aggrading tributaries. We describe the impact of QR, FR and DR on the longitudinal spatial heterogeneity of three indicative characteristics of physical habitat: mainstream grain size, percentage sand and Froude number. To apply our results at broader scales requires specification of relations between QR, FR, DR and easily measured network or basin parameters. This issue is considered, and tentative inferences about the network-scale implications of our results are made.

  3. 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...

  4. Heat transport near sediment-water interfaces with bedforms

    NASA Astrophysics Data System (ADS)

    Cardenas, M. B.; Wilson, J. L.

    2005-12-01

    The mechanical and thermal energy balance of streams, underlying sediments, and adjacent aquifers controls the distribution of lotic organisms. Thus, the energy transport within and between these systems is an issue of utmost importance in terms of understanding their ecology and biogeochemistry. In fast-flow systems, heat advection is equally important as, or more important than, heat conduction. In recent years, heat has been used as a tracer for fluid flow in deep aquifers as well as shallow unconsolidated fluvial deposits. However, recent studies have not addressed how fluid exchange across sediment-water interfaces (SWIs), driven by current-bedform interactions, affects thermal energy transport within the sediments. Moreover, even less is known regarding similar systems subjected to ambient groundwater discharge at a different temperature, e.g., gaining streams. We will present results of multiphysics numerical modeling along SWIs. Turbulent flow within the overlying water column (e.g., a river) is represented by the k-ω closure scheme for the Reynolds-averaged Navier-Stokes equations. Porous media flow within the sediments is governed by the groundwater flow equation. The water column and sediment flow problems are sequentially coupled, with the turbulent water column flow determining the pressure boundary along the SWI. Heat transport within the sediments is governed by the advection-dispersion equation while the flow field is determined a priori by the porous flow problem. Temperature effects on fluid properties are ignored. We do not model heat transport within the water column and instead consider the SWI as a constant-temperature boundary (i.e., the river is well-mixed) for the porous media domain. The numerical modeling is implemented using FEMLAB and CFD-ACE+. Cases with and without ambient groundwater discharge will be presented. Our results have implications not only on lotic ecology but also on the interpretation of past heat tracing experiments and the design of future heat tracer studies.

  5. Contaminated marine sediments: Water column and interstitial toxic effects

    SciTech Connect

    Burgess, R.M.; Schweitzer, K.A.; McKinney, R.A.; Phelps, D.K.

    1993-01-01

    The toxicity that contaminated sediments may introduce into the water column has not been measured extensively. In order to quantify this potential toxicity, the seawater overlying two uncontaminated and three contaminated marine sediments was evaluated in the laboratory with the sea urchin Arbacia punctulata fertilization test. Concentrations of polychlorinated biphenyls (PCBs) and copper, as representative contaminants, were also measured. To characterize sources of toxicity, samples were chemically manipulated using reversed-phase chromatography, cation exchange, and chelation. Water column toxicity and contaminant concentrations were higher in the suspended exposures than in bedded exposures. Interstitial water toxicity and contaminant concentrations were generally greater than either bedded or suspended exposures. Chemical manipulation indicated that the observed toxicity in water column exposures was probably caused by metallic and/or nonionic organic contaminants. Conversely, manipulation of interstitial waters did not result in significantly reduced toxicity, suggesting that other toxicants such as ammonia and hydrogen sulfide may be active.

  6. Contaminated marine sediments: Water column and interstitial toxic effects

    SciTech Connect

    Burgess, R.M.; McKinney, R.A. ); Schweitzer, K.A. ); Phelps, D.K. )

    1993-01-01

    The toxicity that contaminated sediments may introduce into the water column has not been measured extensively. In order to quantify this potential toxicity, the seawater overlying two uncontaminated and three contaminated marine sediments was evaluated in the laboratory with the sea urchin Arbacia punctulata fertilization test. Concentration of polychlorinated biphenyls (PCBs) and copper, as representative contaminants, were also measured. To characterize sources of toxicity, samples were chemically manipulated using reversed-phase chromatography, cation exchange, and chelation. Water column toxicity and contaminant concentrations were higher in the suspended exposures than in bedded exposures. Interstitial water toxicity and contaminant concentrations were generally greater than either bedded or suspended exposures. Chemical manipulation indicated that the observed toxicity in water column exposures was probably caused by metallic and/or nonionic organic contaminants. Conversely, manipulation of interstitial water did not result in significantly reduced toxicity, suggesting that other toxicants such as ammonia and hydrogen sulfide may be active.

  7. Suspended sediment dynamics in the Kromme Rijn river: indication for intense fine sediment exchange between water column and streambed

    NASA Astrophysics Data System (ADS)

    Van den Boomen, R.; Zweers, A. J.; Van der Perk, M.

    2012-04-01

    The limited transparency of the river water of the Kromme Rijn, a dammed distributary of the Rhine River in the Netherlands, restricts the ecological function of the stream and the achievement of the EU-Water Framework Directive targets. To increase water transparency in this river, the 'Hoogheemraadschap De Stichtse Rijnlanden' (HDSR) water authority considers to design one or more large-scale sediment traps. For an optimal design of these possible sediment traps, further knowledge about the local sediment characteristics and sedimentation and resuspension rates is a prerequisite. At the request of the HDSR water authority, we studied the fine sediment characteristics and dynamics in the Kromme Rijn river and its tributaries. Between summer 2010 and summer 2011, eleven monthly water samples were collected from six monitoring locations in the 25 km long reach of the Kromme Rijn river between the inlet from the Nederrijn river and Utrecht. Additional samples were collected from seven monitoring locations in streams and canals discharging into the Kromme Rijn river. The water samples were analysed for suspended sediment concentration and the suspended sediment was analysed for loss on ignition and particle size distribution by laser diffraction. In addition, at these monitoring locations, small sediment traps with an 8 cm circular opening were installed at 0.7 m below the water surface to measure the gross long-term sedimentation rate. These sediment traps were emptied every two months. During the monitoring period, the average sediment load in the Kromme Rijn near the inlet was 112 g/s and decreased to about 90 g/s near Utrecht. The vast majority of the sediment load (91%) in the main branch of the Kromme Rijn originates from the inlet from the Nederrijn river. The 2-16 μm and 16-63 μm particle size classes comprise about 80% of the suspended sediment. The average organic fraction of the suspended sediment was 36%. The sediment collected from the sediment traps were slightly finer and contained less organic matter (20%). The long-term (>2 months) average gross sedimentation flux in the Kromme Rijn river was measured to be 330 g m-2 d-1. As the sediment load only decreases by 20% in the 25 km long studied reach of the Kromme Rijn river and the sediment supply from the tributary streams and canals is limited, this gross sedimentation flux should be compensated by an average gross resuspension flux of approximately 240 g m-2 d-1. This would imply that the river reach length over which the effect of a possible sediment trap is noticeable is limited to about 5-10 km.

  8. Water and bed-sediment quality in the vicinity of Berlin Lake, Ohio, 2001

    USGS Publications Warehouse

    Darner, Robert A.

    2002-01-01

    Berlin Lake, in northeast Ohio, was created by the U.S. Army Corps of Engineers in 1943 and is used primarily for flood control for the upper reaches of the Mahoning River. The area surrounding and under the lake has been tapped for oil and natural gas production. One of the by-products of oil and gas production is concentrated salt water or brine, which might have an effect on the chemical quality of area potable-water sources. This report presents the results of a U.S. Geological Survey baseline study to collect current (2001) water and sediment-quality data and to characterize water quality in the Berlin Lake watershed. Chloride-to-bromide ratios were used to detect the presence of brine in water samples and to indicate possible adverse effects on water quality. Analyses of ground-water samples from domestic wells in the area indicate a source of chloride and bromide, but defining the source would require more data collection. Analyses of specific conductance and dissolved solids indicate that 78 percent (14 of 18) of the ground-water samples exceeded the Secondary Maximum Contaminant Level for dissolved solids in public water supplies of 500 milligrams per liter (mg/L), compared to 6 percent of samples exceeding 500 mg/L in two nearby studies. Surface water was analyzed twice, once each during low-flow and surface runoff conditions. A comparison of the 2001 data to historical chloride concentrations, accounting for seasonal changes, does not indicate an increase in chloride loads for surface water in the area of Berlin Lake. Polycyclic aromatic hydrocarbons were found in bed-sediment samples collected from the mouths of major tributaries to Berlin Lake. Polycyclic aromatic hydrocarbons are produced during the incomplete combustion of organic carbon materials such as wood and fossil fuels, and they are components of petroleum products.

  9. Sediment-water fluxes of mercury in Lavaca Bay, Texas

    SciTech Connect

    Gill, G.A.; Bloom, N.S.; Cappellino, S.; Driscoll, C.T.; Dobbs, C.; McShea, L.; Mason, R.; Rudd, J.W.M.

    1999-03-01

    The aqueous flux of inorganic Hg and monomethyl Hg from sediments to the water column was determined at several sites in Lavaca Bay, an estuary along the Texas Coast, historically impacted by Hg discharges. Diffusive fluxes were calculated at 15 sites using interstitial pore water gradients and compared to direct flux measurements obtained at two sites using benthic flux chambers. The diffusive flux of monomethyl mercury (MMHg), when modeled as a chloride species, varied over 3 orders /of magnitude from 0.2 to 1500 ng m{sup {minus}2} day{sup {minus}1}. Diffusive fluxes determined at a single site revealed that MMHg fluxes varied seasonally; maximal fluxes occurred in late winter to early spring. Flux chamber deployments at an impacted site revealed t hat MMHg was the Hg species entering the water column from sediments and the flux was not in steady-state; there was a strong diurnal signal with most of the MMHg flux occurring during dark periods. The flux of inorganic Hg was smaller and not as easily discernible by this method. The MMHg flux during the dark period was about 6 times greater than the estimated diffusional flux for MMHgCl, suggesting that biological and/or chemical processes near the sediment-water interface were strongly mediating the sediment-water exchange of MMHg.

  10. Solar domestic hot water system installed at Texas City, Texas

    NASA Astrophysics Data System (ADS)

    1980-12-01

    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.

  11. Solar domestic hot water system installed at Texas City, Texas

    NASA Technical Reports Server (NTRS)

    1980-01-01

    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.

  12. Solar heating, cooling and domestic hot water system installed at Columbia Gas System Service Corp. , Columbus, Ohio. Final report

    SciTech Connect

    1980-11-01

    The Solar Energy System located at the Columbia Gas Corporation, Columbus, Ohio, has 2978 ft/sup 2/ of Honeywell single axis tracking, concentrating collectors and provides solar energy for space heating, space cooling and domestic hot water. A 1,200,000 Btu/h Bryan water-tube gas boiler provides hot water for space heating. Space cooling is provided by a 100 ton Arkla hot water fired absorption chiller. Domestic hot water heating is provided by a 50 gallon natural gas domestic storage water heater. Extracts are included from the site files, specification references, drawings, installation, operation and maintenance instructions.

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

    NASA Technical Reports Server (NTRS)

    1980-01-01

    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.

  14. Mineralogical Evidence of Galvanic Corrosion in Domestic, Drinking Water Pipes

    EPA Science Inventory

    Drinking water distribution system (DWDS) piping contains numerous examples of galvanically-coupled metals (e.g., soldered copper pipe joints, copper-lead pipes joined during partial replacements of lead service lines). The possible role of galvanic corrosion in the release of l...

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

    NASA Technical Reports Server (NTRS)

    1980-01-01

    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.

  16. Stream Water and Sediment Phosphorus Equilibrium Concentrations in Ozark Streams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Little information is broadly available on the fate and transport of dissolved phosphorus (DP) in streams draining agricultural and urban catchments, although in-stream processes might have a substantial influence on downstream transport. This study evaluated sediment-water P equilibrium concentrat...

  17. 19. EMPTY SEDIMENTATION TANKS. TOP LAYER OF WATER FLOWS OVER ...

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

    19. EMPTY SEDIMENTATION TANKS. TOP LAYER OF WATER FLOWS OVER TRIANGULATED CHANNELS AND OUT THE RAISED DUCTS TO FILTRATION PLANT. MOVEABLE BOARDS ON BOTTOM ASSIST IN REMOVING SLUDGE. VIEW LOOKING NORTHEAST. FILTER CONTROL BUILDING AT REAR. - F. E. Weymouth Filtration Plant, 700 North Moreno Avenue, La Verne, Los Angeles County, CA

  18. Extraction and concentration of phenolic compounds from water and sediment

    USGS Publications Warehouse

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

    1980-01-01

    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.

  19. Equation of state of supercooled water from the sedimentation profile

    NASA Astrophysics Data System (ADS)

    Yamada, Masako; Stanley, H. Eugene; Sciortino, Francesco

    2003-01-01

    To study the coexistence of two liquid states of water within one simulation box, we implement an equilibrium sedimentation methodwhich involves applying a gravitational field to the system and measuring or calculating the resulting density profile in equilibrium. We simulate a system of particles interacting via the Stillinger-2 (ST2) potential, a model for water. We detect the coexistence of two liquid phases at low temperature.

  20. Relationship between oxygen consumption and sediment-water fluxes of heavy metals in coastal marine sediments

    SciTech Connect

    Shine, J.P.; Ika, R.; Ford, T.E.

    1998-11-01

    The relationship between benthic oxygen demand and the sediment-water flux of six heavy metals (cobalt [Co], nickel [Ni], copper [Cu], zinc [Zn], cadmium [Cd], and lead [Pb]) was examined at two locations: New Bedford Harbor and Buzzards Bay, Massachusetts, USA. Dissolved metal fluxes were measured in laboratory microcosms incubated in the dark at in situ temperatures, and microcosms were collected over different seasons to examine temporal and spatial variability in the fluxes. The net flux of all metals was generally out of the sediments. However, at low rates of benthic oxygen demand, net flux of Pb and Co was into the sediments. When data from the two sites are combined, regression of metal fluxes against benthic oxygen demand was significant for all metals, with all slopes significantly different from zero. The flux values ranged from {minus}1.4 (mmole/m{sup 2}/d)/(mole/mole C){sub sediment} for Zn during winter to 42 (mmole/m{sup 2}/d)/(mole/mole C){sub sediment} for Cd during summer months. The magnitude of the fluxes generally showed the following relationship: Cd > Zn > Co, Ni, Cu > Pb, indicating higher relative mobility for Cd and lower mobility for Pb. The estimated annual fluxes of metals to New Bedford Harbor and Buzzards Bay amount to {approximately}0.06% (Pb) to 25% (Cd) of the inventory of metals in the top 2 cm of sediments and can equal the inventory of metals in the water column on a time scale as short as 7 d for Zn.

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

    SciTech Connect

    Not Available

    2002-10-01

    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.

  2. Relative role of pore water versus ingested sediment in bioavailability of organic contaminants in marine sediments

    SciTech Connect

    Forbes, T.L.; Hansen, R.; Kure, L.K.; Forbes, V.E.; Giessing, A. |

    1998-12-01

    Experimental data for fluoranthene and feeding selectivity in combination with reaction-diffusion modeling suggest that ingestion of contaminated sediment may often be the dominant uptake pathway for deposit-feeding invertebrates in sediments. A dietary absorption efficiency of 56% and accompanying forage ratio of 2.4 were measured using natural sediment that had been dual-labeled ({sup 14}C:{sup 51}Cr) with fluoranthene and fed to the marine deposit-feeding polychaete Capitella species I. Only 3 to 4% of the total absorption could be accounted for by desorption during gut passage. These data were then used as input into a reaction-diffusion model to calculate the importance of uptake from ingested sediment relative to pore-water exposure. The calculations predict a fluoranthene dietary uptake flux that is 20 to 30 times greater than that due to pore water. Factors that act to modify or control the formation of local chemical gradients, boundary layers, or dietary absorption rates including particle selection or burrow construction will be important in determining the relative importance of potential exposure pathways. From a chemical perspective, the kinetics of the adsorption and desorption process are especially important as they will strongly influence the boundary layer immediately surrounding burrowing animals or irrigated tubes. The most important biological factors likely include irrigation behavior and burrow density and size.

  3. Sediment dispersal and accumulation off the present Huanghe (Yellow River) delta as impacted by the Water-Sediment Regulation Scheme

    NASA Astrophysics Data System (ADS)

    Wu, Xiao; Bi, Naishuang; Yuan, Ping; Li, Song; Wang, Houjie

    2015-12-01

    Surface sediment samples from 15 stations around the present Huanghe (Yellow River) river mouth were collected before, during and after the Water-Sediment Regulation Scheme (WSRS) in 2010 for grain size analysis. Hydrographic surveys conducted simultaneously at stations along three transects off the river mouth during the WSRS in 2013 were used to investigate the dispersal and accumulation of the Huanghe sediment off the present Huanghe subaqueous delta. During the WSRS period, the diluted water from the river covered all over the study area within the surface layer, whereas high-concentrated sediment was found in the bottom layers and to be limited in nearshore area shallower than 12 m, indicating that the buoyant river plume was the main sediment dispersal pattern during the WSRS. At the early stage of the WSRS when large amount of clear water was released from the Xiaolangdi Reservoir, sediment eroded from the downstream riverbed in the lower reaches increased the median grain size of surface sediment at the river mouth. During the second stage when water discharge was reduced but sediment discharge was dramatically increased, the fine-grained sediment derived from the Xiaolangdi Reservoir mixed with the previously deposited coarser surface sediment, leading to the decreasing median grain size of surface sediment that approached to be poorly sorted. After the physical sorting from winter storms, the surface sediment was redistributed and varied regularly with water depth. As the median grain size of suspended sediment discharge to the sea has been significantly increased due to the WSRS, the river-delivered sediment mostly accumulated in the nearshore area, which effectively extended the subaerial delta and steepened the subaqueous slope off the present river mouth.

  4. Bacteriological quality and risk assessment of the imported and domestic bottled mineral water sold in Fiji.

    PubMed

    Zeenat, A; Hatha, A A M; Viola, L; Vipra, K

    2009-12-01

    Considering the popularity of bottled mineral water among indigenous Fijians and tourists alike, a study was carried out to determine the bacteriological quality of different bottled waters. A risk assessment was also carried out. Seventy-five samples of bottled mineral water belonging to three domestic brands and 25 samples of one imported brand were analysed for heterotrophic plate count (HPC) bacteria and faecal coliforms. HPC counts were determined at 22 degrees C and 37 degrees C using R2A medium and a membrane filtration technique was used to determine the faecal coliform (FC) load in 100 ml of water on mFC agar. Between 28 and 68% of the samples of the various domestic brands failed to meet the WHO standard of 100 colony forming units (cfu) per 100 ml at 22 degrees C and 7% of these also tested positive for faecal coliforms. All imported bottled mineral water samples were within WHO standards. A risk assessment of the HPC bacteria was carried out in terms of beta haemolytic activity and antibiotic resistance. More than 50% of the isolates showed beta haemolytic activity and were multi-drug resistant. While the overall quality of the product was generally good, there is a need to enforce stringent quality standards for the domestic bottlers to ensure the safety of consumers. PMID:19590131

  5. Tomographic imaging of residual hydrocarbon in water saturated unconsolidated sediments

    NASA Astrophysics Data System (ADS)

    Li, Xun

    2002-08-01

    Determining the amount and distribution of residual hydrocarbon in granular media is important for monitoring secondary and tertiary recovery processes during hydrocarbon production. The distribution of residual hydrocarbon is affected by the structure of the granular media (layering, grain, pore size, etc.), and the method used to produce oil (single well, multi-well, etc.). Seismic technique are often used to monitor the recovery process, thus, it is required that the effect of structure and hydrocarbon distribution be understood. The objectives of this thesis work is to determine if acoustic methods can (1) delineate sediment structure caused by variation in grain size and (2) delineate the amount and spatial distribution of residual hydrocarbon. Naturally occurring sediments are often complicated in composition and structure that results in a range of seismic attenuation mechanisms. For this study, synthetic sediments with idealized 3-D sediment structures were created from glass beads (with known composition and geometry) saturated with two fluid phase: water and paraffin wax. A series of control experiments were performed using different saturation techniques to (1) explore the immiscible fluid displacement processes and (2) to study the effect of amount and the spatial distribution of the immiscible fluid residue on the acoustic response. An acoustic tomographic approach was used to delineate the 3-D sediment structure and to study the effect of sediment structure on the amount and the spatial distribution of the immiscible fluid. From the control experiments, it was determined that the saturation method affected the residual wax distribution in the pores. The residual wax distribution can be categorized into four types, i.e. bridging, thin fingering, cements at grain contacts, and patchy saturation. The tomographic experiments determined that sediment structure caused by a variation in grain size could barely be determined seismically. However, the 3-D sediment structure was clearly determined when residual paraffin resided in the sediment. Even residual saturation of less than 1% altered the seismic signal of the sediments. Seismic-wave attenuation and velocity is sensitive to alteration of the grain contact stiffness even for only a few percent residual hydrocarbon saturation and to spatial features that are 1/100 of a wavelength. Thus the affect of micro-scale phenomena on macro-scale measurements of seismic wave attenuation and velocity cannot be ignored.

  6. Development of three-pipe DHC system with once-through domestic hot water supply

    SciTech Connect

    Not Available

    1991-03-01

    Wide use of computers in the United States and installation of different heat recovery systems in buildings reduce the requirements for heating. At the same time, heating, cooling and domestic hot water are often required simultaneously or in a daily cycle (morning heating and afternoon cooling). Also at any given time, some buildings in a service area may require heating, while others require cooling. The present method of serving these needs is the use of four-pipe system with supply and return pipes for heating and domestic hot water service and supply and return pipes for cooling. Both such systems typically circulate water from the district heating and cooling (DHC) plant through user heat exchangers back to the DHC plant in a closed cycle. In order to reduce costs, a three-pipe system is proposed. One pipe supplies hot water for heating and domestic hot water, the second pipe supplies chilled water, and the third pipe is a common return. The purpose of this project was to perform a preliminary investigation of the three-pipe system with once-through hot water supply. In order to accomplish this goal the following tasks have been performed: (1) Technical and economic analysis of the applicability of the three-pipe system in different climatic zones of the United States, (2) Assessment of the corrosion control methods and treatment in the DHC systems, (3) Assessment of the existing code requirements as applied to the three-pipe system with once-through water supply, and (4) Corrosion and water quality field tests in the Jamestown District Heating System as applicable to the once-through water supply. 10 refs., 11 figs.

  7. IMPORTANCE OF INTERSTITIAL, OVERLYING WATER AND WHOLE SEDIMENT EXPOSURES TO BIOACCUMUALTION BY MARINE BIVALVES

    EPA Science Inventory

    During the performance of contaminated sediment studies using nonpolar pollutants, like polyclorinated biphenyls (PCBs), with marine organisms, the routes of exposure can include whole sediment, overlying waters and interstitial waters (assuming no feeding). These routes can be f...

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

    SciTech Connect

    Not Available

    1994-07-01

    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.)

  9. Water-sediment controversy in setting environmental standards for selenium.

    PubMed

    Hamilton, S J; Lemly, A D

    1999-11-01

    A substantial amount of laboratory and field research on selenium effects to biota has been accomplished since the national water quality criterion was published for selenium in 1987. Many articles have documented adverse effects on biota at concentrations below the current chronic criterion of 5 microg/L. This commentary will present information to support a national water quality criterion for selenium of 2 microg/L, based on a wide array of support from federal, state, university, and international sources. Recently, two articles have argued for a sediment-based criterion and presented a model for deriving site-specific criteria. In one example, they calculate a criterion of 31 microg/L for a stream with a low sediment selenium toxicity threshold and low site-specific sediment total organic carbon content, which is substantially higher than the national criterion of 5 microg/L. Their basic premise for proposing a sediment-based method has been critically reviewed and problems in their approach are discussed. PMID:10581116

  10. Case study of the effectiveness of passive grease trap for management on domestic kitchen waste water

    NASA Astrophysics Data System (ADS)

    Nidzamuddin, M. Y.; Juffrizal, K.; Mustapha, F.; Zulfattah, Z. M.; Tan, C. F.; Taha, M. M.; Hidayah, I.; Hilwa, M. Z.

    2015-05-01

    Household waste, generally known as trash or garbage is mostly includes food wastes, product packaging, and other miscellaneous inorganic wastes that are coming from domestic household. Grease waste such as oil and fats can contaminate water and also clot on pipes provoking blockages. Thus, waste water from kitchen sink need a proper way of filtration. Grease trap developed in this paper is viable in trapping the grease residue. The experiments have been conducted in controlled environment and the objectives are to investigate the effectiveness of grease trap by proving the existence of retention time and the expected ratio of collected water and oil during experiment process using a prototype model.

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

    SciTech Connect

    Not Available

    1994-06-01

    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 .

  12. 30 CFR 77.216-4 - Water, sediment or slurry impoundments and impounding structures; reporting requirements...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Water, sediment or slurry impoundments and....216-4 Water, sediment or slurry impoundments and impounding structures; reporting requirements... of the initial plan approval, the person owning, operating, or controlling a water, sediment,...

  13. 30 CFR 77.216-4 - Water, sediment or slurry impoundments and impounding structures; reporting requirements...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Water, sediment or slurry impoundments and....216-4 Water, sediment or slurry impoundments and impounding structures; reporting requirements... of the initial plan approval, the person owning, operating, or controlling a water, sediment,...

  14. 30 CFR 77.216-3 - Water, sediment, or slurry impoundments and impounding structures; inspection requirements...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Water, sediment, or slurry impoundments and... COAL MINES Surface Installations 77.216-3 Water, sediment, or slurry impoundments and impounding structures; inspection requirements; correction of hazards; program requirements. (a) All water, sediment,...

  15. 30 CFR 77.216-3 - Water, sediment, or slurry impoundments and impounding structures; inspection requirements...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Water, sediment, or slurry impoundments and... COAL MINES Surface Installations 77.216-3 Water, sediment, or slurry impoundments and impounding structures; inspection requirements; correction of hazards; program requirements. (a) All water, sediment,...

  16. 30 CFR 77.216 - Water, sediment, or slurry impoundments and impounding structures; general.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Water, sediment, or slurry impoundments and... WORK AREAS OF UNDERGROUND COAL MINES Surface Installations 77.216 Water, sediment, or slurry... structures which impound water, sediment, or slurry shall be required if such an existing or...

  17. 30 CFR 77.216-3 - Water, sediment, or slurry impoundments and impounding structures; inspection requirements...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Water, sediment, or slurry impoundments and... COAL MINES Surface Installations 77.216-3 Water, sediment, or slurry impoundments and impounding structures; inspection requirements; correction of hazards; program requirements. (a) All water, sediment,...

  18. 30 CFR 77.216-3 - Water, sediment, or slurry impoundments and impounding structures; inspection requirements...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Water, sediment, or slurry impoundments and... COAL MINES Surface Installations 77.216-3 Water, sediment, or slurry impoundments and impounding structures; inspection requirements; correction of hazards; program requirements. (a) All water, sediment,...

  19. 30 CFR 77.216 - Water, sediment, or slurry impoundments and impounding structures; general.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Water, sediment, or slurry impoundments and... WORK AREAS OF UNDERGROUND COAL MINES Surface Installations 77.216 Water, sediment, or slurry... structures which impound water, sediment, or slurry shall be required if such an existing or...

  20. 30 CFR 77.216 - Water, sediment, or slurry impoundments and impounding structures; general.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Water, sediment, or slurry impoundments and... WORK AREAS OF UNDERGROUND COAL MINES Surface Installations 77.216 Water, sediment, or slurry... structures which impound water, sediment, or slurry shall be required if such an existing or...

  1. 30 CFR 77.216 - Water, sediment, or slurry impoundments and impounding structures; general.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Water, sediment, or slurry impoundments and... WORK AREAS OF UNDERGROUND COAL MINES Surface Installations 77.216 Water, sediment, or slurry... structures which impound water, sediment, or slurry shall be required if such an existing or...

  2. Remote Sensing of Suspended Sediments and Shallow Coastal Waters

    NASA Technical Reports Server (NTRS)

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

    2002-01-01

    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.

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

    NASA Technical Reports Server (NTRS)

    1980-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

    1980-07-01

    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.

  5. Assessment of physico-chemical properties and metal contents of water and sediments of Bodo Creek, Niger Delta, Nigeria

    PubMed Central

    Vincent-Akpu, Ijeoma Favour; Tyler, Andrew N.; Wilson, Clare; Mackinnon, Gillian

    2015-01-01

    Some physico-chemical properties and the concentrations of the metals Fe, Mn, Ni, Cd, Cr, Co, Cu, Pb, and Zn in water and sediments were examined from September 2011 to January 2012 in Bodo Creek, where oil spills have been recurrent. Temperature, pH, total dissolved solid, conductivity, salinity, dissolved oxygen, biological oxygen demand (BOD), chemical oxygen demand (COD), total hardness, sulfate, nitrate, and phosphate were determined in surface water. Particle size, total organic matter (TOM), and pH were also determined in the sediments. The parameters were within permissible limits except the mean values of BOD, COD, total hardness, and sulfate that exceeded levels permissible for domestic use. The sediments consisted mainly of sand, with TOM ranging from 0.2% to 5.5%. With the exception of cadmium that was below detection limit, metal levels (mg kg−1) in the sediments were 12 (Mn), 1070 (Fe), 10 (Cu), 10 (Zn), 5.3 (Cr), 1.1 (Pb), 1.0 (Ni), and 0.5 (Co) while in water they were 24, 98, 21, 6.9, 4.0, 0.6, 0.18, and 0.16, respectively. The latter were higher than World Health Organization recommended permissible levels for both surface and drinking water. PMID:26681819

  6. Characterizing Water, Sediment, Nutrients, and Contaminant Fluxes in Coastal Egypt

    NASA Astrophysics Data System (ADS)

    Peterson, Richard N.; El-Gamal, Ayman

    2010-03-01

    Marine Constituent Dynamics in Coastal Egypt; Alexandria, Egypt, 20 November 2009; The Egyptian coastal area is a highly dynamic region in which materials (water, sediment, nutrients, and contaminants) are transported from various sources to the Mediterranean and Red seas. At a workshop in Egypt, U.S. and Egyptian scientists discussed these largely unquantified processes and how they interact to drive coastal ecology. A major goal of the workshop was to identify the most pressing research priorities for the region for both scientific and management purposes. The workshop concluded by recommending that international multidisciplinary efforts be undertaken to characterize water, nutrient, sediment, and contaminant delivery fluxes and mechanisms to coastal regions of the Nile Delta.

  7. Report on water quality, sediment and water chemistry data for water and sediment samples collected from source areas to Melton Hill and Watts Bar reservoirs

    SciTech Connect

    Tomaszewski, T.M.; Bruggink, D.J.; Nunn, D.L.

    1995-08-18

    Contamination of surface water and sediments in the Clinch River and Watts Bar Reservoir (CR/WBR) system as a result of past and present activities by the US Department of Energy (DOE) on the Oak Ridge Reservation (ORR) and also activities by non-ORR facilities are being studied by the Clinch River Environmental Restoration Program (CR-ERP). Previous studies have documented the presence of heavy metals, organics, and radionuclides in the sediments of reservoirs in the vicinity. In support of the CR-ERP, during the summer of 1991, TVA collected and evaluated water and sediment samples from swimming areas and municipal water intakes on Watts Bar Reservoir, Melton Hill Reservoir and Norris Reservoir, which was considered a source of less-contaminated reference or background data. Despite the numerous studies, until the current work documented by this report, relatively few sediment or water samples had been collected by the CR-ERP in the immediate vicinity of contaminant point sources. This work focused on water and sediment samples taken from points immediately downstream from suspected effluent point sources both on and off the ORR. In August and September, 1994, TVA sampled surface water and sediment at twelve locations in melton Hill and Watts Bar Reservoirs.

  8. Integrating the simulation of domestic water demand behaviour to an urban water model using agent based modelling

    NASA Astrophysics Data System (ADS)

    Koutiva, Ifigeneia; Makropoulos, Christos

    2015-04-01

    The urban water system's sustainable evolution requires tools that can analyse and simulate the complete cycle including both physical and cultural environments. One of the main challenges, in this regard, is the design and development of tools that are able to simulate the society's water demand behaviour and the way policy measures affect it. The effects of these policy measures are a function of personal opinions that subsequently lead to the formation of people's attitudes. These attitudes will eventually form behaviours. This work presents the design of an ABM tool for addressing the social dimension of the urban water system. The created tool, called Urban Water Agents' Behaviour (UWAB) model, was implemented, using the NetLogo agent programming language. The main aim of the UWAB model is to capture the effects of policies and environmental pressures to water conservation behaviour of urban households. The model consists of agents representing urban households that are linked to each other creating a social network that influences the water conservation behaviour of its members. Household agents are influenced as well by policies and environmental pressures, such as drought. The UWAB model simulates behaviour resulting in the evolution of water conservation within an urban population. The final outcome of the model is the evolution of the distribution of different conservation levels (no, low, high) to the selected urban population. In addition, UWAB is implemented in combination with an existing urban water management simulation tool, the Urban Water Optioneering Tool (UWOT) in order to create a modelling platform aiming to facilitate an adaptive approach of water resources management. For the purposes of this proposed modelling platform, UWOT is used in a twofold manner: (1) to simulate domestic water demand evolution and (2) to simulate the response of the water system to the domestic water demand evolution. The main advantage of the UWAB - UWOT model integration is that it allows the investigation of the effects of different water demand management strategies to an urban population's water demand behaviour and ultimately the effects of these policies to the volume of domestic water demand and the water resources system. The proposed modelling platform is optimised to simulate the effects of water policies during the Athens drought period of 1988-1994. The calibrated modelling platform is then applied to evaluate scenarios of water supply, water demand and water demand management strategies.

  9. Preliminary assessment of heavy metal contamination in surface water and sediments from Honghu Lake, East Central China

    NASA Astrophysics Data System (ADS)

    Hu, Ying; Qi, Shihua; Wu, Chenxi; Ke, Yanping; Chen, Jing; Chen, Wei; Gong, Xiangyi

    2012-03-01

    Heavy metal concentrations in surface water and sediments collected from Honghu Lake in Hubei Province, China were analyzed, and ecological risks were evaluated according to the sediment quality guidelines. The results showed that the average concentrations of heavy metals in surface water were ranked as: As>Zn> Cu>Cr>Pb>Ni>Cd>Hg. In comparison with results reported in other rivers and the background values, The Honghu Lake was polluted by As, Cr, Pb, Cu and Ni. Most of metals might be mainly from fertilizers, industrial effluent and domestic wastewater around the lake. Heavy metals concentrations were relatively higher in the inlet area than in other areas. Negative correlations were observed between most heavy metals and pH, while a significant positive correlation was present between Zn, Cd and Pb. In the sediment core, Cu, Zn, Cr and Ni showed a decreasing trend while Cd present an increasing trend. The decrease of As, Cu, Zn, Cr and Ni in the 1990s might due to the flood event in 1998. The analysis of ecological risk assessment based on sediment quality guidelines suggested that heavy metals in most sediments from the Honghu Lake had moderate toxicity, with Cr being the highest priority pollutant.

  10. Can control of soil erosion mitigate water pollution by sediments?

    PubMed

    Rickson, R J

    2014-01-15

    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

  11. EARTHQUAKE HAZARDS TO DOMESTIC WATER DISTRIBUTION SYSTEMS IN SALT LAKE COUNTY, UTAH.

    USGS Publications Warehouse

    Highland, Lynn M.

    1985-01-01

    A magnitude-7. 5 earthquake occurring along the central portion of the Wasatch Fault, Utah, may cause significant damage to Salt Lake County's domestic water system. This system is composed of water treatment plants, aqueducts, distribution mains, and other facilities that are vulnerable to ground shaking, liquefaction, fault movement, and slope failures. Recent investigations into surface faulting, landslide potential, and earthquake intensity provide basic data for evaluating the potential earthquake hazards to water-distribution systems in the event of a large earthquake. Water supply system components may be vulnerable to one or more earthquake-related effects, depending on site geology and topography. Case studies of water-system damage by recent large earthquakes in Utah and in other regions of the United States offer valuable insights in evaluating water system vulnerability to earthquakes.

  12. Quality of Water from Domestic Wells in Principal Aquifers of the United States, 1991-2004: Overview of Major Findings

    USGS Publications Warehouse

    DeSimone, Leslie A.; Hamilton, Pixie A.; Gilliom, Robert J.

    2009-01-01

    More than 43 million people - about 15 percent of the U.S. population - rely on domestic wells as their source of drinking water (Hutson and others, 2004). The quality and safety of water from domestic wells, also known as private wells, are not regulated by the Federal Safe Drinking Water Act or, in most cases, by state laws. Rather, individual homeowners are responsible for maintaining their domestic well systems and for monitoring water quality. The lack of regular monitoring of domestic wells makes periodic assessments at national, regional, and local scales important sources for providing information about this key source of drinking water. This study from the National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey (USGS) assesses water-quality conditions for about 2,100 domestic wells. The sampled wells are located in 48 states and in parts of 30 regionally extensive aquifers used for water supply in the United States. As many as 219 properties and contaminants, including pH, major ions, nutrients, trace elements, radon, pesticides, and volatile organic compounds (VOCs), were measured. Fecal indicator bacteria and additional radionuclides were analyzed for a smaller number of wells. The large number of contaminants assessed and the broad geographic coverage of the present study provides a foundation for an improved understanding of the quality of water from the major aquifers tapped by domestic supply wells in the United States.

  13. A sediment resuspension and water quality model of Lake Okeechobee

    USGS Publications Warehouse

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

    1997-01-01

    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.

  14. 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 adsorptiondesorption of nutrients by sediment, and the release of nutrie...

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

    NASA Astrophysics Data System (ADS)

    Choudhury, Parthasarathi; Sil, Briti Sundar

    2010-05-01

    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.

  16. Methane efflux from lake sediments through water lilies.

    PubMed

    Dacey, J W; Klug, M J

    1979-03-23

    During winter, when water lilies have no surface leaves, the gases in the rhizome lacunae approach equilibrium with the gases of the sediment water. The resulting increase of internal pressure is manifested by the sustained streams of bubbles (up to 37 percent methane and 6 percent carbon dioxide) that escape when emerging leaves are torn in the spring. Methane continues to enter the roots and rhizome during summer, rapidly moves up the petioles, and passes out through the emergent leaves into the atmosphere. PMID:17841139

  17. Removal of sediment and bacteria from water using green chemistry.

    PubMed

    Buttice, Audrey L; Stroot, Joyce M; Lim, Daniel V; Stroot, Peter G; Alcantar, Norma A

    2010-05-01

    Although nearly all newly derived water purification methods have improved the water quality in developing countries, few have been accepted and maintained for long-term use. Field studies indicate that the most beneficial methods use indigenous resources, as they are both accessible and accepted by communities they help. In an effort to implement a material that will meet community needs, two fractions of mucilage gum were extracted from the Opuntia ficus-indica cactus and tested as flocculation agents against sediment and bacterial contamination. As diatomic ions are known to affect both mucilage and promote cell aggregation, CaCl(2) was studied in conjunction and compared with mucilage as a bacteria removal method. To evaluate performance, ion-rich waters that mimic natural water bodies were prepared. Column tests containing suspensions of the sediment kaolin exhibited particle flocculation and settling rates up to 13.2 cm/min with mucilage versus control settling rates of 0.5 cm/min. Bacillus cereus tests displayed flocculation and improved settling times with mucilage concentrations lower than 5 ppm and removal rates between 97 and 98% were observed for high bacteria concentration tests (>10(8) cells/ml). This natural material not only displays water purification abilities, but it is also affordable, renewable and readily available. PMID:20369814

  18. Evaluating Domestic Hot Water Distribution System Options with Validated Analysis Models

    SciTech Connect

    Weitzel, E.; Hoeschele, E.

    2014-09-01

    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. Transient System Simulation Tool (TRNSYS) is a full distribution system developed that has been validated using field monitoring data and then exercised in a number of climates to understand climate impact on performance. In this study, the Building America team built upon previous analysis modeling 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. 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.

  19. 30 CFR 77.216-5 - Water, sediment or slurry impoundments and impounding structures; abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Surface Installations 77.216-5 Water, sediment or..., sediment, or slurry impoundment and impounding structure which meets the requirements of 30 CFR 77.216(a... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Water, sediment or slurry impoundments...

  20. A novel tracer technique for the assessment of fine sediment dynamics in urban water management systems.

    PubMed

    Spencer, K L; Droppo, I G; He, C; Grapentine, L; Exall, K

    2011-04-01

    Urban storm water run off can reduce the quality of receiving waters due to high sediment load and associated sediment-bound contaminants. Consequently, urban water management systems, such as detention ponds, that both modify water quantity through storage and improve water quality through sediment retention are frequently-used best management practices. To manage such systems effectively and to improve their efficiency, there is a need to understand the dynamics (transport and settling) of sediment, and in particular the fine sediment fraction (<63 ?m) and its associated contaminants within urban storm water management systems. This can be difficult to achieve, as modelling the transport behaviour of fine-grained and cohesive sediment is problematic and field-based measurements can be costly, time-consuming and unrepresentative. The aim of this study was to test the application of a novel cohesive sediment tracer and to determine fine sediment transport dynamics within a storm water detention pond. The cohesive sediment tracer used was a holmium labelled montmorillonite clay which flocculated and had similar size and settling velocity to the natural pond sediment it was intended to mimic. The tracer demonstrated that fine sediment was deposited across the entire pond, with the presence of reed beds and water depth being important factors for maximising sediment retention. The results of the sediment tracer experiment were in good agreement with those of a mathematical sediment transport model. Here, the deposited sediment tracer was sampled by collecting and analysing surface pond sediments for holmium. However, analysis and sampling of the three dimensional suspended tracer 'cloud' may provide more accurate information regarding internal pond sediment dynamics. PMID:21420140

  1. Survey of the Mutagenicity of Surface Water, Sediments, and Drinking Water from the Penobscot Indian Nation.

    EPA Science Inventory

    Survey of the Mutagenicity of Surface Water, Sediments, andDrinking Water from the Penobscot Indian NationSarah H. Warren, Larry D. Claxton,1, Thomas J. Hughes,*, Adam Swank,Janet Diliberto, Valerie Marshall, Daniel H. Kusnierz, Robert Hillger, David M. DeMariniNational Health a...

  2. 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...

  3. Patterns of domestic water use in rural areas of Zimbabwe, gender roles and realities

    NASA Astrophysics Data System (ADS)

    Makoni, Fungai S.; Manase, Gift; Ndamba, Jerry

    This paper presents practical experiences into the pattern of domestic water use, benefits and the gender realities. The study was undertaken in two districts of Zimbabwe, Mt Darwin and Bikita covering a total of 16 villages. The study aimed to assess the patterns of domestic water use, benefits derived from its use among the gender groups. Methodology for participatory assessment (MPA) was used for data collection and was done in a participatory manner. Traditionally most people in Zimbabwe are subsistence farmers who rely on rain fed agriculture. Where primary water sources are available such as shallow wells, family wells, deep wells and boreholes households use the water for household water and sanitation, irrigate small family gardens as well as their livestock. The survey established that women and men usually rank uses of water differently. In the two districts it was evident that women are playing more roles in water use and it is apparent that women are most often the users, managers and guardians of household water and hygiene. Women also demonstrated their involvement in commercial use of water, using water for livestock watering (20%) as well as brick moulding (21%). These involvement in commercial use were influenced by survival economics as well as the excess and reliability of the supply. The different roles and incentives in water use of women and men was demonstrated in how they ranked the benefits of water and sanitation. Men ranked clean drinking water among others as a top priority while women ranked improved health and hygiene and reduced distance as top priority. Overall the benefits highlighted by the communities and especially women were meeting the practical needs such as better access to water and reducing their work load. The assessment demonstrated the active role of women in water sources management highlighting quality, reliability and restrictions to their use. Though the communities gave the impression that decision making in the sitting and construction of water points was equally among the gender groups, however it was evident that men have a greater role than women in public decision making.

  4. Evaluating Domestic Hot Water Distribution System Options With Validated Analysis Models

    SciTech Connect

    Weitzel, E.; Hoeschele, M.

    2014-09-01

    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.

  5. Hydrogeologic, water-quality, streamflow, bottom-sediment analyses, and biological data near the Wayne County landfill, Wayne County, Tennessee

    USGS Publications Warehouse

    Quinones, F.; Bradfield, Arthur D.; Wescott, J.B.

    1992-01-01

    This report summarizes the data collected as part of a hydrogeologic investigation to determine the effects of the Wayne County landfill on local water quality. The investigation was conducted from 1988 through 1989 by the U.S. Geological Survey in cooperation with the Tennessee Department of Health and Environment, Division of Superfund. The landfill was closed in November 1984 after allegations that contaminants from the landfill were affecting the quality of water from domestic wells in the Banjo Branch-Hardin Hollow valley. Test well construction data; water-quality data for selected wells, seeps, and surface-water sites: streamflow data from Banjo Branch; analyses of bottom-sediment samples: and biological data for the study area are documented in this report.

  6. 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...

  7. 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 ...

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

    USGS Publications Warehouse

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

    1994-01-01

    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.

  9. Hydrogeology of the Unconsolidated Sediments, Water Quality, and Ground-Water/Surface-Water Exchanges in the Methow River Basin, Okanogan County, Washington

    USGS Publications Warehouse

    Konrad, Christopher P.; Drost, Brian W.; Wagner, Richard J.

    2003-01-01

    The U.S. Geological Survey, in cooperation with Okanogan County, investigated the hydrogeology of the unconsolidated sedimentary deposits in the Methow River Basin, the quality of surface and ground waters, and the exchanges between ground water and surface water. Alluvium (Qa) and glaciofluvial sediments (Qga) deposited during the Quaternary period constitute the primary aquifer in the Methow River Basin, which is used as a source of water for domestic and public-water supplies and for maintaining streamflow during seasonal dry periods. The sediments form a nearly continuous unit along the valley bottom from above the Lost River to the confluence of the Methow and Columbia Rivers, covering more than 45 square miles of the basin?s surface. There are no distinct units within the deposit that can be identified across or along the valley except for fragments of a possible lake bed near the town of Twisp. Ground-water levels in the unconsolidated aquifer are highest during the summer and lowest in the winter and early spring. Ground water and surface water, sampled during June and September 2001, generally were of high quality. Only two samples from domestic and municipal wells indicated the possibility of ground-water contamination from nitrate and arsenic concentrations. In both cases, potential contamination was isolated to an individual well. No trends in water quality were apparent when comparing the results of this investigation with previous studies. The flow of water between rivers and aquifers is important for regulating the availability of water resources for in-stream and out-of-stream uses in the Methow River Basin. Ground-water discharge from the unconsolidated aquifer to the Methow River from Lost River to Pateros ranged from an estimated 153,000 acre-ft in water year 2001 to 157,000 acre-ft in water year 2002. In contrast, ground-water discharge to the lower Twisp River from Newby Creek to near Twisp ranged from 4,700 acre-ft in water year 2001 to 9,200 acre-ft in water year 2002. The Methow and Twisp Rivers, among others in the basin, are major sources of recharge for the unconsolidated aquifer, particularly during high-flow periods in May and June. Aquifer recharge by both rivers increased with streamflow in water year 2002 compared to water year 2001 as indicated by daily losses of streamflow. Aquifer recharge by the Methow River from Lost River to Pateros was estimated to be 82,000 acre-ft in water year 2001 and 137,000 acre-ft in water year 2002. Aquifer recharge by the Twisp River from Newby Creek to near Twisp was estimated to be 2,000 acre-ft in water year 2001 and 6,400 acre-ft in water year 2002. Seepage from unlined irrigation canals also recharges the unconsolidated aquifer during the late spring and summer and may contribute as much 38,000 acre-ft annually to aquifer recharge in the basin. Some portion of this ground water returns to rivers as indicated by a seasonal increase in ground-water discharge in the Methow River from Winthrop to Twisp and in the lower Twisp River during late summer and early autumn. Although the increase is likely due primarily to irrigation canal seepage, however, fluvial recharge during the summer also may have contributed to the increase. The increased rate of ground-water discharge decays by January in both reaches.

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

    PubMed

    Craft, D

    1985-12-01

    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 water and high trace metal concentrations may exist in this area of the reservoir. These data suggested that the tailings material should be contained or removed prior to reservoir filling. Other sites in the reservoir basin exhibited water quality considered normal for reservoirs of similar elevation and basin geology. Near the proposed dam, anaerobic conditions could develop rapidly due to available concentrations of organic carbon, and the subsequent release of Zn, Fe, and Mn may pose a water quality problem. At the sampling site near Keetley, simulation data indicated that anaerobic conditions will not develop as quickly or be as severe as conditions expected near the dam. Overall, the availability of nitrogen and phosphorus in the Provo River and Jordanelle sediments indicated that problems with algal blooms may exist in the reservoir. Also presented is a brief discussion of the advantages and disadvantages associated with microcosm sediment-water simulation. PMID:24213801

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

    USGS Publications Warehouse

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

    2000-01-01

    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.

  12. Quantitative bacterial examination of domestic water supplies in the Lesotho Highlands: water quality, sanitation, and village health.

    PubMed Central

    Kravitz, J. D.; Nyaphisi, M.; Mandel, R.; Petersen, E.

    1999-01-01

    Reported are the results of an examination of domestic water supplies for microbial contamination in the Lesotho Highlands, the site of a 20-year-old hydroelectric project, as part of a regional epidemiological survey of baseline health, nutritional and environmental parameters. The population's hygiene and health behaviour were also studied. A total of 72 village water sources were classified as unimproved (n = 23), semi-improved (n = 37), or improved (n = 12). Based on the estimation of total coliforms, which is a nonspecific bacterial indicator of water quality, all unimproved and semi-improved water sources would be considered as not potable. Escherichia coli, a more precise indicator of faecal pollution, was absent (P < 0.001) in most of the improved water sources. Among 588 queried households, only 38% had access to an "improved" water supply. Sanitation was a serious problem, e.g. fewer than 5% of villagers used latrines and 18% of under-5-year-olds had suffered a recent diarrhoeal illness. The study demonstrates that protection of water sources can improve the hygienic quality of rural water supplies, where disinfection is not feasible. Our findings support the WHO recommendation that E. coli should be the principal microbial indicator for portability of untreated water. Strategies for developing safe water and sanitation systems must include public health education in hygiene and water source protection, practical methods and standards for water quality monitoring, and a resource centre for project information to facilitate programme evaluation and planning. PMID:10593031

  13. Heteroaggregation and sedimentation rates for nanomaterials in natural waters.

    PubMed

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

    2014-01-01

    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

  14. Chemical extraction of microorganisms from water-saturated, packed sediment.

    PubMed

    Ugolini, Fabio; Schroth, Martin H; Brgmann, Helmut; Hammes, Frederik; Zeyer, Josef

    2013-06-01

    Microbial characterization of aquifers should combine collection of suspended and attached microorganisms (biofilms). This study investigated chemical extraction of microorganisms from water-saturated, packed sediment containing established biofilms. It compares the use of different detachment-promoting agent (DPA) solutions with tap water as eluent in column experiments. Extraction efficiency was determined from cell concentrations in the column effluent. Adenosine triphosphate concentrations were measured to confirm cell extraction and as an indicator of cell membrane integrity. Quality of extracted bacterial communities was assessed by comparing their terminal restriction fragment length polymorphism profiles with destructively sampled sediment-community profiles. Extraction efficiency increased more than 8-fold when deionized water, D-amino acids, or enzymes were used as a DPA. Community profiles recovered by individual DPA solutions showed more pronounced differences at the level of rare microbial groups, whereas abundant groups appeared ubiquitous across treatments. These results suggest that comparison of communities extracted by different DPAs can provide improved information on the occurrence of rare microbial groups in biofilms. PMID:23833813

  15. A memory model of sedimentation in water reservoirs

    NASA Astrophysics Data System (ADS)

    Caputo, Michele; Carcione, José M.

    2013-01-01

    SummaryWe consider a one-dimensional model of water reservoir, where the sediment is diffusing according to the Fourier law modified with the introduction of a derivative of fractional distributed orders as memory formalism. The fractional order is equivalent to a time-varying diffusivity and the distributed orders represent a variety of memory mechanisms to model a sediment with a varied distribution of grain sizes. Using the Laplace transform (LT), we find the solution in the case when the flux is constant at the source and is arbitrarily given at the output. Then, the time-domain solution is obtained by means of a numerical Fourier transform. We apply a one-dimensional simplified model, with the diffusion governed by two parameters, to the Quarto Nuovo (Italy) reservoir, where the flux of sediment at the output is obtained from observed data. It is found that the flux increases when one of the parameters defining the diffusion model, the pseudo-diffusivity, is increasing or when the other parameter defining the diffusion, the order of fractional differentiation, is decreasing. When the latter parameter is nil, one obtains the classic diffusion with maximum flux.

  16. [Water-Sediment Partition of Polycyclic Aromatic Hydrocarbons in Karst Underground River].

    PubMed

    Lan, Jia-cheng; Sun, Yu-chuan; Xiao, Shi-zhen

    2015-11-01

    Based on polycyclic aromatic hydrocarbons (PAHs) field data of dissolved phase and sediment phase, partition coefficient K(p) in sediment-water interface from Laolongdong underground river was obtained. The concentration of PAHs in water and sediment and partition coefficient K(p) in sediment-water interface were studied. The results showed PAHs concentrations were 81.5-8 089 ng x L(-1) with a mean value (1 439 ± 2 248) ng x L(-1) in water and 58.2-1 051 ng x g(-1) with an average (367.9 ± 342.6) ng x g(-1) in sediment. The dominant PAHs were 2-3 rings PAHs in water and sediment. However, high rings PAHs obviously enriched in the sediment. Partition coefficients varied from 55.74 to 46 067 L x kg(-1) in sediment-water interface, increasing with the rise of PAH compounds. All the organic carbon partition in sediment-water interface were higher than predicate values based on typical model of equilibrium distribution indicated that PAHs were strongly adsorbed in sediment. The linear free-energy relationship coefficient between K(oc) value and octanol-water partition coefficient K(ow) was 0.75, but the slope was lower than 1, indicating that sediment in Laolongdong underground river had weakly lipophilic characteristics and adsorption ability for PAHs. PMID:26910993

  17. 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

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

    2006-01-01

    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.

  18. 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)

    March, H.; Hernndez, M.; Saur, D.

    2014-11-01

    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).

  19. [Changes of bacterial community structure on reusing domestic sewage of Daoxianghujing Hotel to landscape water].

    PubMed

    Zhu, Jing-nan; Wang, Xiao-dan; Zhai, Zhen-hua; Ma, Wen-lin; Li, Rong-qi; Wang, Xue-lian; Li, Yan-hong

    2010-05-01

    A 16S rDNA library was used to evaluate the bacterial diversity and identify dominant groups of bacteria in different treatment pools in the domestic sewage system of the Beijing Daoxianghujing Hotel. The results revealed that there were many types of bacteria in the hotel domestic sewage, and the bacterial Shannon-Weaver diversity index was 3.12. In addition, epsilon Proteobacteria was found to be the dominant group with the ratio of 32%. In addition, both the CFB phylum, Fusobacteria, gamma Proteobacteria and Firmicutes were also reached to 9%-15%. After treated with the reclaimed water station, the bacterial Shannon-Weaver diversity index was reduced to 2. 41 and beta Proteobacteria became the dominant group and occupied 73% of the total clones. However, following artificial wetland training, the bacterial Shannon-Weaver diversity index in the sample increased to 3.38, Actinobacteria arrived to 33% and became the most dominant group; Cyanobacteria reached to 26%, and was the second dominant group. But, the control sample comprised 38% Cyanobacteria, and mainly involved in Cyanobium, Synechoccus and Microcystis, with ratios of 47.1%, 17.6% and 8.8%, respectively. Some bacteria of Microcystis aenruginosa were also detected, which probably resulted in the light bloom finally. Therefore, the bacterial diversity and community structures changed in response to treatment of the hotel domestic sewage; there was no cyanobacteria bloom explosion in the treated water. This study will aid in investigation the changes of microbial ecology in different types of water and providing the useful information for enhancing the cyanobacteria blooms control from ecological angle. PMID:20623868

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

    PubMed

    Harwood, John J

    2014-01-01

    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

  1. Analysis of solar domestic hot water systems from a system perspective

    SciTech Connect

    Murphy, L.M.; Farrington, R.; Noreen, D.

    1980-03-01

    Six solar domestic hot water systems tested at the National Bureau of Standards have been analyzed. Results indicate that the thermosyphon system delivered the most solar energy to the load per dollar of initial investment (the air system delivered the least) and that direct systems performed better than indirect systems. Storage losses from the double tank systems were greater than expected, and this significantly reduced the relative performance of these systems. Further, the use of pumps, fans, controls, and solenoid valves in the pumped systems can reduce the net energy savings of the solar system by up to 30%.

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

    NASA Astrophysics Data System (ADS)

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

    2012-06-01

    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.

  3. Summary report on water quality, sediment and water chemistry data for water and sediment samples collected from source areas to Melton Hill and Watts Bar reservoirs

    SciTech Connect

    Tomaszewski, T.M.; Bruggink, D.J.; Nunn, D.L.

    1995-08-01

    Contamination of surface water and sediments in the Clinch River and Watts Bar Reservoir (CR/WBR) system as a result of past and present activities by the US Department of Energy (DOE) on the Oak Ridge Reservation (ORR) and also activities by non-ORR facilities are being studied by the Clinch River Environmental Restoration Program (CR-ERP). Previous studies have documented the presence of heavy metals, organics, and radionuclides in the sediments of reservoirs in the vicinity. In support of the CR-ERP, during the summer of 1991, TVA collected and evaluated water and sediment samples from swimming areas and municipal water intakes on Watts Bar Reservoir, Melton Hill Reservoir (which is considered part of the Clinch River and Watts Bar Reservoir System), and Norris Reservoir, which was considered a source of less-contaminated reference or background data. Results of this study indicated that the levels of contamination in the samples from the Watts Bar and Melton Hill Reservoir sites did not pose a threat to human health. Despite the numerous studies, until the current work documented by this report, relatively few sediment or water samples had been collected by the CR-ERP in the immediate vicinity of contaminant point sources. This work focused on water and sediment samples taken from points immediately downstream from suspected effluent point sources both on and off the ORR. In August and September, 1994, TVA sampled surface water and sediment at twelve locations in Melton Hill and Watts Bar Reservoirs. Eleven of the sampling sites were selected based on existence of pollutant discharge permits, known locations of hazardous waste sites, and knowledge of past practices. The twelfth sample site was selected as a relatively less contaminated reference site for comparison purposes.

  4. The importance of domestic water quality management in the context of faecal-oral disease transmission.

    PubMed

    Trevett, Andrew Francis; Carter, Richard C; Tyrrel, Sean F

    2005-09-01

    The deterioration of drinking water quality following its collection from a community well or standpipe and during storage in the home has been well documented. However, there is a view that post-supply contamination is of little public health consequence. This paper explores the potential health risk from consuming re-contaminated drinking water. A conceptual framework of principal factors that determine the pathogen load in household drinking water is proposed. Using this framework a series of hypotheses are developed in relation to the risk of disease transmission from re-contaminated drinking water and examined in the light of current literature and detailed field observation in rural Honduran communities. It is shown that considerable evidence of disease transmission from re-contaminated drinking water exists. In particular the type of storage container and hand contact with stored drinking water has been associated with increased incidence of diarrhoeal disease. There is also circumstantial evidence linking such factors as the sanitary conditions in the domestic environment, cultural norms and poverty with the pathogen load of household stored drinking water and hence the risk of disease transmission. In conclusion it is found that re-contaminated drinking water represents a significant health risk especially to infants, and also to those with secondary immunodeficiency. PMID:16209030

  5. U.S. Biofuel Policies and Domestic Shifts in Agricultural Land Use and Water Balances

    NASA Astrophysics Data System (ADS)

    Teter, J.; Yeh, S.; Mishra, G. S.

    2014-12-01

    Policies promoting domestic biofuels production could lead to significant changes in cropping patterns. Types of direct and indirect land use change include: switching among crops (displacement), expanding cropped area (extensification), and altering water/soil management practices (e.g. irrigation, tillage) (intensification). Most studies of biofuels water use impacts calculate the water intensity of biofuels in liters of irrigated/total evapotranspired water per unit energy of biofuels. But estimates based on this approach are sensitive to assumptions (e.g. co-product allocation, system boundaries), and do not convey policy-relevant information, as highlighted by the issue of land use change. We address these shortcomings by adopting a scenario-based approach that combines economic modeling with crop-water modeling of major crops and biofuel feedstocks. This allows us to holistically compare differences in water balances across policy scenarios in an integrated economic/agricultural system. We compare high spatial resolution water balance estimates under three hypothetical policy scenarios: 1) a counterfactual no-policy scenario, 2) modified Renewable Fuels Standard mandates (M-RFS2), & 3) a national Low Carbon Fuel Standard plus a modified RFS2 scenario (LCFS+RFS2). Differences between scenarios in crop water balances (i.e. transpiration, evaporation, runoff, groundwater infiltration, & irrigation) are regional and are a function of changes in land use patterns (i.e. displacement, intensification, & extensification), plus variation in crop water-use characteristics. Cropped land area increases 6.2% and 1.6% under M-RFS2 and LCFS+RFS2 scenarios, respectively, by 2030. Both policy scenarios lead to reductions in net irrigation volumes nationally compared to the no-policy scenario, though more irrigation occurs in regions of the Midwest and West. The LCFS+RFS2 reduces net irrigation water use by 3.5 times more than M-RFS2. However, both policies drive extensification and hence greater net transpiration (i.e. economically useful water consumption), at the expense of groundwater infiltration, which recharges surface & groundwater stocks. Our study illustrates potential tradeoffs in water resource availability that might result from domestic policies promoting bioenergy.

  6. A multilayer shallow water system for polydisperse sedimentation

    NASA Astrophysics Data System (ADS)

    Fernndez-Nieto, E. D.; Kon, E. H.; Morales de Luna, T.; Brger, R.

    2013-04-01

    This work considers the flow of a fluid containing one disperse substance consisting of small particles that belong to different species differing in size and density. The flow is modelled by combining a multilayer shallow water approach with a polydisperse sedimentation process. This technique allows one to keep information on the vertical distribution of the solid particles in the mixture, and thereby to model the segregation of the particle species from each other, and from the fluid, taking place in the vertical direction of the gravity body force only. This polydisperse sedimentation process is described by the well-known Masliyah-Lockett-Bassoon (MLB) velocity functions. The resulting multilayer sedimentation-flow model can be written as a hyperbolic system with nonconservative products. The definitions of the nonconservative products are related to the hydrostatic pressure and to the mass and momentum hydrodynamic transfer terms between the layers. For the numerical discretization a strategy of two steps is proposed, where the first one is also divided into two parts. In the first step, instead of approximating the complete model, we approximate a reduced model with a smaller number of unknowns. Then, taking advantage of the fact that the concentrations are passive scalars in the system, we approximate the concentrations of the different species by an upwind scheme related to the numerical flux of the total concentration. In the second step, the effect of the transference terms defined in terms of the MLB model is introduced. These transfer terms are approximated by using a numerical flux function used to discretize the 1D vertical polydisperse model, see Brger et al. [ R. Brger, A. Garca, K.H. Karlsen, J.D. Towers, A family of numerical schemes for kinematic flows with discontinuous flux, J. Eng. Math. 60 (2008) 387-425]. Finally, some numerical examples are presented. Numerical results suggest that the multilayer shallow water model could be adequate in situations where the settling takes place from a suspension that undergoes horizontal movement.

  7. Metabolism of niclosamide in sediment and water systems

    USGS Publications Warehouse

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

    2004-01-01

    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.

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

    PubMed

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

    2014-08-01

    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

  9. Microplastics in coastal sediments from Southern Portuguese shelf waters.

    PubMed

    Frias, J P G L; Gago, J; Otero, V; Sobral, P

    2016-03-01

    Microplastics are well-documented pollutants in the marine environment that result from fragmentation of larger plastic items. Due to their long chemical chains, they can remain in the environment for long periods of time. It is estimated that the vast majority (80%) of marine litter derives from land sources and that 70% will sink and remain at the bottom of the ocean. Microplastics that result from fragmentation of larger pieces of plastic are common to be found in beaches and in the water surface. The most common microplastics are pellets, fragments and fibres. This work provides original data of the presence of microplastics in coastal sediments from Southern Portuguese shelf waters, reporting on microplastic concentration and polymer types. Microplastic particles were found in nearly 56% of sediment samples, accounting a total of 31 particles in 27 samples. The vast majority were microfibers (25), identified as rayon fibres, and fragments (6) identified as polypropylene, through infrared spectroscopy (μ-FTIR). The concentration and polymer type data is consistent with other relevant studies and reports worldwide. PMID:26748246

  10. Regulation of plasma arginine vasotocin in conscious water-deprived domestic fowl.

    PubMed

    Stallone, J N; Braun, E J

    1986-04-01

    Radioimmunoassay methods were employed to quantitatively characterize secretion of the avian antidiuretic hormone [arginine vasotocin (AVT)] by the hypothalamo-neurohypophyseal system (HNS) of the conscious domestic fowl in response to chronic dehydration. Water deprivation permitted characterization of AVT secretion in response to the combined stimuli of extracellular hyperosmolality and hypovolemia; the subsequent repletion of extracellular volume permitted separation of potential osmotic and volemic factors involved in the regulation of AVT secretion. In normally hydrated birds, plasma AVT (PAVT) and plasma osmolality (Posm) averaged 2.2 +/- 0.3 microU/ml (10.5 +/- 1.4 pg/ml) and 309.3 +/- 0.7 mosmol/kg H2O, respectively (means +/- SE). With water deprivation, PAVT and Posm of the birds increased in parallel in a curvilinear manner to maxima of 13.1 +/- 0.6 microU/ml (62.4 +/- 2.9 pg/ml) and 346.6 +/- 2.0 mosmol/kg H2O, respectively, at 96 h of dehydration. The isosmotic repletion of extracellular volume at 96 h by acute intravenous infusion failed to alter 96-h PAVT values. The results indicate that AVT secretion is closely linked to the state of hydration during negative fluid balance in the domestic fowl. Analysis of the data indicated that increases in PAVT that occur with dehydration are mediated primarily by extracellular hyperosmolality and that the HNS of the domestic fowl is relatively insensitive to the simultaneous hypovolemia incurred with fluid deprivation. PMID:3963234

  11. Radioactive dating: Studies on ground water and sediments. (Latest citations from the Selected Water Resources Abstracts database). Published Search

    SciTech Connect

    Not Available

    1994-10-01

    The bibliography contains citations concerning radioactive dating of ground water and sediments. Articles discuss ground water movement and recharge; and lake, marine, and glacial sediments. Citations address dating techniques using isotopes of carbon, lead, uranium, radium, and tritium. Studies on sedimentation rate, water quality, aquifer characteristics, geological survey, and glacial history are presented. (Contains a minimum of 103 citations and includes a subject term index and title list.)

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

    SciTech Connect

    1995-09-01

    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)

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

    SciTech Connect

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

    1990-01-01

    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.

  14. Cryptosporidium and Giardia in Humans, Domestic Animals, and Village Water Sources in Rural India.

    PubMed

    Daniels, Miles E; Shrivastava, Arpit; Smith, Woutrina A; Sahu, Priyadarshi; Odagiri, Mitsunori; Misra, Pravas R; Panigrahi, Pinaki; Suar, Mrutyunjay; Clasen, Thomas; Jenkins, Marion W

    2015-09-01

    Cryptosporidium parvum and Giardia lamblia are zoonotic enteric protozoa of significant health concern where sanitation, hygiene, and water supplies are inadequate. We examined 85 stool samples from diarrhea patients, 111 pooled fecal samples by species across seven domestic animal types, and water from tube wells (N = 207) and ponds (N = 94) across 60 villages in coastal Odisha, India, for Cryptosporidium oocysts and Giardia cysts to measure occurrence, concentration/shedding, and environmental loading rates. Oocysts/cysts were detected in 12% of diarrhea patients. Detection ranged from 0% to 35% for Cryptosporidium and 0% to 67% for Giardia across animal hosts. Animal loading estimates indicate the greatest contributors of environmental oocysts/cysts in the study region are cattle. Ponds were contaminated with both protozoa (oocysts: 37%, cysts: 74%), as were tube wells (oocysts: 10%, cysts: 14%). Future research should address the public health concern highlighted from these findings and investigate the role of domestic animals in diarrheal disease transmission in this and similar settings. PMID:26123963

  15. Cryptosporidium and Giardia in Humans, Domestic Animals, and Village Water Sources in Rural India

    PubMed Central

    Daniels, Miles E.; Shrivastava, Arpit; Smith, Woutrina A.; Sahu, Priyadarshi; Odagiri, Mitsunori; Misra, Pravas R.; Panigrahi, Pinaki; Suar, Mrutyunjay; Clasen, Thomas; Jenkins, Marion W.

    2015-01-01

    Cryptosporidium parvum and Giardia lamblia are zoonotic enteric protozoa of significant health concern where sanitation, hygiene, and water supplies are inadequate. We examined 85 stool samples from diarrhea patients, 111 pooled fecal samples by species across seven domestic animal types, and water from tube wells (N = 207) and ponds (N = 94) across 60 villages in coastal Odisha, India, for Cryptosporidium oocysts and Giardia cysts to measure occurrence, concentration/shedding, and environmental loading rates. Oocysts/cysts were detected in 12% of diarrhea patients. Detection ranged from 0% to 35% for Cryptosporidium and 0% to 67% for Giardia across animal hosts. Animal loading estimates indicate the greatest contributors of environmental oocysts/cysts in the study region are cattle. Ponds were contaminated with both protozoa (oocysts: 37%, cysts: 74%), as were tube wells (oocysts: 10%, cysts: 14%). Future research should address the public health concern highlighted from these findings and investigate the role of domestic animals in diarrheal disease transmission in this and similar settings. PMID:26123963

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

    PubMed Central

    Alary, M; Joly, J R

    1991-01-01

    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

  17. 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...

  18. 30 CFR 77.216-1 - Water, sediment or slurry impoundments and impounding structures; identification.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Water, sediment or slurry impoundments and... AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Surface Installations 77.216-1 Water, sediment or..., operating, or controlling the structure, shall be located on or immediately adjacent to each water,...

  19. 30 CFR 77.216-1 - Water, sediment or slurry impoundments and impounding structures; identification.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Water, sediment or slurry impoundments and... AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Surface Installations 77.216-1 Water, sediment or..., operating, or controlling the structure, shall be located on or immediately adjacent to each water,...

  20. 30 CFR 77.216-1 - Water, sediment or slurry impoundments and impounding structures; identification.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Water, sediment or slurry impoundments and... AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Surface Installations 77.216-1 Water, sediment or..., operating, or controlling the structure, shall be located on or immediately adjacent to each water,...

  1. 30 CFR 77.216-1 - Water, sediment or slurry impoundments and impounding structures; identification.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Water, sediment or slurry impoundments and... AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Surface Installations 77.216-1 Water, sediment or..., operating, or controlling the structure, shall be located on or immediately adjacent to each water,...

  2. 30 CFR 77.216-1 - Water, sediment or slurry impoundments and impounding structures; identification.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Water, sediment or slurry impoundments and... AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Surface Installations 77.216-1 Water, sediment or..., operating, or controlling the structure, shall be located on or immediately adjacent to each water,...

  3. LIGHT DEPENDENCE OF SEDIMENT-WATER NUTRIENT EXCHANGE IN A GULF OF MEXICO

    EPA Science Inventory

    The flux of dissolved nutrients between sediments and overlying water is an important component of nutrient processing in estuaries. These fluxes can be linked to sediment metabolism, which in shallow estuaries can be affected by light. Sediment cores were collected at sight stat...

  4. Laboratory experiments on dam-break flow of water-sediment mixtures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dams induce sedimentation and store significant amounts of sediment as they age; therefore, dam failures often involve the release of sediment-laden water to the downstream floodplain. In particular, tailings dams, which are constructed to impound mining wastes, can cause devastating damage when the...

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

    EPA Science Inventory

    We introduce a new modelSTAND (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...

  6. 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...

  7. Enhancement of natural circulation type domestic solar hot water system performance by using a wind turbine

    NASA Astrophysics Data System (ADS)

    Ramasamy, K. K.; Srinivasan, P. S. S.

    2011-08-01

    Performance improvement of existing 200 litres capacity natural convection type domestic solar hot water system is attempted. A two-stage centrifugal pump driven by a vertical axis windmill having Savonius type rotor is added to the fluid loop. The windmill driven pump circulates the water through the collector. The system with necessary instrumentation is tested over a day. Tests on Natural Circulation System (NCS) mode and Wind Assisted System (WAS) mode are carried out during January, April, July and October, 2009. Test results of a clear day are reported. Daily average efficiency of 25-28 % during NCS mode and 33-37 % during WAS mode are obtained. With higher wind velocities, higher collector flow rates and hence higher efficiencies are obtained. In general, WAS mode provides improvements in efficiency when compared to NCS mode.

  8. Cold-Climate Solar Domestic Hot Water Systems: Cost/Benefit Analysis and Opportunities for Improvement

    SciTech Connect

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

    2005-01-01

    To determine potential for reduction in the cost of saved energy (COSE) for cold-climate solar domestic hot water (SDHW) systems, COSE was computed for three types of cold climate water heating systems. For each system, a series of cost-saving measures was considered: (1) balance of systems (BOS): tank, heat exchanger, and piping-valving measures; and (2) four alternative lower-cost collectors. Given all beneficial BOS measures in place, >50% reduction of COSE was achievable only with selective polymer collectors at half today's selective collector cost. In all three system types, today's metal-glass selective collector achieved the same COSE as the hypothesized non-selective polymer collector.

  9. Discharge, suspended sediment, bedload, and water quality in Clear Creek, western Nevada, water years 2010-12

    USGS Publications Warehouse

    Huntington, Jena M.; Savard, Charles S.

    2015-01-01

    During this study, total annual sediment loads ranged from 355 tons per year in 2010 to 1,768 tons per year in 2011 and were significantly lower than the previous study (water years 200407). Bedload represented between 29 and 38 percent of total sediment load in water years 201012, and between 72 and 90 percent of the total sediment load in water years 200407, which indicates a decrease in bedload between study periods. Annual suspended-sediment loads in water years 201012 indicated no significant change from water years 200407. Mean daily discharge was significantly lower in water years 201012 than in waters years 200407 and may be the reason for the decrease in bedload that resulted in a lower total sediment load.

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

    PubMed

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

    2004-02-01

    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 buffaloes (Carabao) and 61 river buffaloes (Murrah, Jafarabadi, and Mediterranean), sampled in Brazil and Italy. We detected 36 mitochondrial haplotypes with 128 polymorphic sites. Pooled with published data of South-East Asian and Australian water buffaloes and based on comprehensive median-joining network and population demography analyses we show evidence that both river and swamp buffaloes decent from one domestication event, probably in the Indian subcontinent. However, the today swamp buffaloes have an unravelled mitochondrial history, which can be explained by introgression of wild water buffalo mtDNA into domestic stocks. We are also discussing indications for an independent domestication of buffaloes in China. PMID:14715223

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

    PubMed

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

    2012-08-01

    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

  12. Evolution of the earth's water mass and sedimentation

    SciTech Connect

    Timofeev, P.P.; Kholodov, V.N.; Zverev, V.P.

    1986-05-01

    The origin of the hydrosphere has been discussed repeatedly. It has become clear that one cannot explain the current mass of water on the earth without invoking the most modern cosmogenic hypotheses, on the one hand, and without reconstructing the processes of metamorphism, granitization, and basalt melting, on the other. As all these problems are still at the stage of scientific hypothesis, any treatment of the change in water volume through geologic time can only be a very crude approximation. Recently, it has become clear that there is a fairly complicated interaction between the different parts of the lithosphere and the ocean water. The formation of water bound in various crustal shells (basalt, granite, and sediment) is summarized. It is concluded that in the remote period (up to 2 billion years ago), shallow lake-type basins were the most abundant, while in the period from 2 billion years to 0.2 billion years, there were extensive shallow intercontinental and epicontinental seas with an average depth of 0.5-2 km; there probably were no oceans resembling modern ones at that time. The modern oceans were effectively formed at the boundary between the Mesozoic and Cenozoic, when the volume of the hydrosphere attained its maximum value, while relief contrast resulted in depressions 5-6 km deep. 15 references.

  13. Parameterization of biogeochemical sediment-water fluxes using in situ measurements and a diagenetic model

    NASA Astrophysics Data System (ADS)

    Laurent, A.; Fennel, K.; Wilson, R.; Lehrter, J.; Devereux, R.

    2016-01-01

    Diagenetic processes are important drivers of water column biogeochemistry in coastal areas. For example, sediment oxygen consumption can be a significant contributor to oxygen depletion in hypoxic systems, and sediment-water nutrient fluxes support primary productivity in the overlying water column. Moreover, nonlinearities develop between bottom water conditions and sediment-water fluxes due to loss of oxygen-dependent processes in the sediment as oxygen becomes depleted in bottom waters. Yet, sediment-water fluxes of chemical species are often parameterized crudely in coupled physical-biogeochemical models, using simple linear parameterizations that are only poorly constrained by observations. Diagenetic models that represent sediment biogeochemistry are available, but rarely are coupled to water column biogeochemical models because they are computationally expensive. Here, we apply a method that efficiently parameterizes sediment-water fluxes of oxygen, nitrate and ammonium by combining in situ measurements, a diagenetic model and a parameter optimization method. As a proof of concept, we apply this method to the Louisiana Shelf where high primary production, stimulated by excessive nutrient loads from the Mississippi-Atchafalaya River system, promotes the development of hypoxic bottom waters in summer. The parameterized sediment-water fluxes represent nonlinear feedbacks between water column and sediment processes at low bottom water oxygen concentrations, which may persist for long periods (weeks to months) in hypoxic systems such as the Louisiana Shelf. This method can be applied to other systems and is particularly relevant for shallow coastal and estuarine waters where the interaction between sediment and water column is strong and hypoxia is prone to occur due to land-based nutrient loads.

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

    PubMed Central

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

    2013-01-01

    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

  15. Microbiological evaluation of bottled non-carbonated ("still") water from domestic brands in Greece.

    PubMed

    Venieri, D; Vantarakis, A; Komninou, G; Papapetropoulou, M

    2006-03-01

    The microbiological quality of 1,527 samples of bottled non-carbonated ('still') mineral water, purchased from retail outlets and derived from 10 manufacturing companies in Greece, was investigated during the period 1995-2003. Applying the membrane filter technique, the aliquots of water samples (250 ml) were analyzed for the presence and enumeration of total coliforms, Escherichia coli, Enterococcus spp. and Pseudomonas aeruginosa. Also, aerobic bacteria were counted as Heterotrophic Plate Count (HPC) ml(-1) at 22 and 37 degrees C. Positive samples for the parameters tested varied significantly among brands with an overall percentage of 13.95% bottled water samples noncompliant with the Greek water regulation. Microorganisms isolated from the samples tested were identified as species of Pseudomonas, Aeromonas, Pasteurella, Citrobacter, Flavobacterium, Providencia and Enterococcus. The most frequent isolated microorganism during the period of the study was P. aeruginosa. Generally, bacterial load of the samples tested ranged in low levels. The purpose of the current study was to evaluate the microbiological quality of the bottled water provided by domestic brands in the Greek market during the period 1995-2003. PMID:16271413

  16. Domestic rainwater harvesting to improve water supply in rural South Africa

    NASA Astrophysics Data System (ADS)

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

    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.

  17. 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 ...

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

    PubMed Central

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

    2014-01-01

    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

  19. Estimating suspended sediment concentrations in surface waters of the Amazon River wetlands from Landsat images

    SciTech Connect

    Mertes, L.A.K.; Smith, M.O.; Adams, J.B. )

    1993-03-01

    A method has been developed, based on spectral mixture analysis, to estimate the concentration of suspended sediment in surface waters of the Amazon River wetlands from Landsat MSS and TM images. Endmembers were derived from laboratory reflectance measurements of water-sediment mixtures with a range of sediment concentrations. Using these references spectra, the authors applied a linear mixture analysis to multispectral images after accounting for instrument and atmosphere gains and offsets. Sediment concentrations were estimated for individual pixels from the mixture analysis results based on a nonlinear calibration curve relating laboratory sediment concentrations and reflectance to endmember fractions. The uncertainty in the sediment concentrations derived from this analysis for three Amazon images is predicted to be within [plus minus] 20 mg/L, and the concentrations fall within a range of concentrations of suspended sediment that were measured at several times and places in the field over the past 15 years. The emphasis of their work is to use the patterns of sediment concentrations to compute the approximate volumes of sediment that are transferred between the main channel and floodplain of the Amazon River. However, the methodology can be applied universally if the optical properties of water and sediment at the site are known, and it is, therefore, useful for the study of suspended sediment concentrations in surface waters of wetlands elsewhere.

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

    USGS Publications Warehouse

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

    1993-01-01

    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.

  1. Phytoremediation of domestic wastewaters in free water surface constructed wetlands using Azolla pinnata.

    PubMed

    Akinbile, Christopher O; Ogunrinde, Temitope A; Che Bt Man, Hasfalina; Aziz, Hamidi Abdul

    2016-01-01

    Two constructed wetlands, one with Azolla pinnata plant (CW1) and the other without (CW2) for treating domestic wastewaters were developed. Fifteen water parameters which include: Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), Total Phosphorus (TP), Total Nitrogen (TN), Ammoniacal Nitrogen (NH3N), Turbidity, pH, Electrical Conductivity (EC), Iron (Fe), Magnesium (Mg), Manganese (Mn), and heavy metals such as Lead (Pb) and Zinc (Zn) were analyzed using standard laboratory procedures. The experiments were conducted in two (dry and wet) seasons simultaneously. Results showed considerable reductions in all parameters and metals including Zn in CW1 compared with CW2 in the two seasons considered while Pb and Mn were not detected throughout the study. Zn concentration levels reduced significantly in both seasons just as removal efficiencies of 70.03% and 64.51% were recorded for CW1 while 35.17% and 33.45% were recorded for CW2 in both seasons. There were no significant differences in the removal efficiencies of Fe in both seasons as 99.55%, 59.09%, 88.89%, and 53.56% were recorded in CW1 and CW2 respectively. Azolla pinnata has proved effective in domestic wastewater phytoremediation studies. PMID:26121232

  2. The chemical quality of self-supplied domestic well water in the United States

    USGS Publications Warehouse

    Focazio, M.J.; Tipton, D.; Dunkle, Shapiro S.; Geiger, L.H.

    2006-01-01

    Existing water quality data collected from domestic wells were summarized to develop the first national-scale retrospective of self-supplied drinking water sources. The contaminants evaluated represent a range of inorganic and organic compounds, and although the data set was not originally designed to be a statistical representation of national occurrence, it encompasses large parts of the United States including at least some wells sampled in every state and Puerto Rico. Inorganic contaminants were detected in many of the wells, and concentrations exceeded the U.S. EPA maximum contaminant levels (MCLs; federal drinking water standards used to regulate public drinking water quality) more often than organic contaminants. Of the inorganic constituents evaluated, arsenic concentrations exceeded the MCL (10 ??g/L) in ???11% of the 7580 wells evaluated, nitrate exceeded the MCL (10 mg/L) in ???8% of the 3465 wells evaluated, uranium-238 exceeded the MCL (30 ??g/L) in ???4% of the wells, and radon-222 exceeded 300 and 4000 pCi/L (potential drinking water standards currently under review by the U.S. EPA) in ???75% and 9% of the wells, respectively. The MCLs for total mercury and fluoride were each exceeded in <1% of the wells evaluated. The MCL was exceeded in <1% of all wells for all anthropogenically derived organic contaminants evaluated and was not exceeded for many contaminants. In addition, 10 contaminants evaluated do not currently have an MCL. Atrazine, however, was detected in 24% of the wells evaluated and was the most frequently detected organic contaminant of the 28 organic contaminants evaluated in this study. Simazine and metolachlor each were detected in ???9% of all wells and tied for second in frequency of detection for organic contaminants. The third and fourth most frequently detected organic contaminants were methyl tert-butyl ether (MTBE) (6%) and chloroform (5%), respectively. Because the water quality of domestic wells is not federally regulated or nationally monitored, this study provides a unique, previously nonexistent, perspective on the quality of the self-supplied drinking water resources used by ???45 million Americans in the United States. Copyright ?? 2006 The Author(s).

  3. Suspended sediment control and water quality conservation through riparian vegetation:

    NASA Astrophysics Data System (ADS)

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

    2009-04-01

    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 μm), 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 compare spatial distribution of the soil use and the erosion features of the Geomorphology map. To every situation a degree of risk is assigned and connected to riparian vegetation map of the stream. The worst conditions are in the presence of landslides, calanchive basins, road lines very close and parallel to the stream and where the agricultural mechanisation of land and the erosion features are present. The methods allow us to detect the situations of insufficiency (both in quality and quantity) of the riparian vegetation in comparison to the degree of risk of soil erosion in the strip buffer and the riverbank stability. Finally, they can help us to suggest ways to improve or replant the existing vegetation on the stream bank identify , according to specific and multifunctional sylvicoltural models. This research programme was initiated thanks to the Reno Watershed Authority, ARPA (Regional Agency for Environmental Prevention, and Renana Land Reclamation Society.

  4. Contribution of Streptomyces in sediment to earthy odor in the overlying water in Xionghe Reservoir, China.

    PubMed

    Zuo, Yanxia; Li, Lin; Zhang, Ting; Zheng, Lingling; Dai, Gongyuan; Liu, Liming; Song, Lirong

    2010-12-01

    Musty and earthy odors frequently characterize the source water and fish of the Xionghe Reservoir in China. Although odorous compounds and odor-producing cyanobacteria have been analyzed in surface water, potential odorants in sediments and their contribution to the water body have remained uninvestigated. In this study, we examined the odorous compounds and possible odor-producers in the sediments and overlying water of Xionghe Reservoir from November 2007 to October 2008. High concentrations of geosmin (up to 5280.1ngkg(-1)dw(-1)) were detected in sediments, and eight strains of Streptomyces isolated from sediments were verified as producers of geosmin and/or 2-MIB in M liquid medium by HSPME-GC-MS. Geosmin concentrations in the overlying water were correlated with those in the sediments (r=0.838, p<0.05). In vitro studies showed that geosmin in the overlying water was released from the sediment, and that within 12 days the amount released from the sediment was 21.4-51.4%. Concentrations of geosmin in sediments were positively correlated with organic matter (r=0.642, p<0.01), total nitrogen (r=0.606, p<0.01) and Chl a (r=0.674, p<0.01), and were negatively associated with temperature (r=-0.425, p<0.05). This study indicates that odorous compounds that are released from sediments should be taken into account when assessing the sources of these odorants in waters. PMID:20800260

  5. Microbial Diversity in Water and Sediment of Lake Chaka, an Athalassohaline Lake in Northwestern China

    PubMed Central

    Jiang, Hongchen; Dong, Hailiang; Zhang, Gengxin; Yu, Bingsong; Chapman, Leah R.; Fields, Matthew W.

    2006-01-01

    We employed culture-dependent and -independent techniques to study microbial diversity in Lake Chaka, a unique hypersaline lake (32.5% salinity) in northwest China. It is situated at 3,214 m above sea level in a dry climate. The average water depth is 2 to 3 cm. Halophilic isolates were obtained from the lake water, and halotolerant isolates were obtained from the shallow sediment. The isolates exhibited resistance to UV and gamma radiation. Microbial abundance in the sediments ranged from 108 cells/g at the water-sediment interface to 107 cells/g at a sediment depth of 42 cm. A major change in the bacterial community composition was observed across the interface. In the lake water, clone sequences affiliated with the Bacteroidetes were the most abundant, whereas in the sediments, sequences related to low G+C gram-positive bacteria were predominant. A similar change was also present in the archaeal community. While all archaeal clone sequences in the lake water belonged to the Halobacteriales, the majority of the sequences in the sediments were related to those previously obtained from methanogenic soils and sediments. The observed changes in the microbial community structure across the water-sediment interface were correlated with a decrease in salinity from the lake water (32.5%) to the sediments (approximately 4%). Across the interface, the redox state also changed from oxic to anoxic and may also have contributed to the observed shift in the microbial community. PMID:16751487

  6. The role of domestic tap water on Acanthamoeba keratitis in non-contact lens wearers and validation of laboratory methods.

    PubMed

    Koltas, Ismail Soner; Eroglu, Fadime; Erdem, Elif; Yagmur, Meltem; Tan?r, Ferdi

    2015-09-01

    Acanthamoeba is increasingly recognized as an important cause of keratitis in non-contact lens wearers while contact lens wear is the leading risk factor for Acanthamoeba keratitis (AK). It is unlikely that the Acanthamoeba colonization is a feature which is effective only in patient's homes with infectious keratitis since the organism has been isolated from domestic tap water. Two hundred and thirty-one (231) corneal scrapings were taken from infectious keratitis cases, and four contact lens solutions and domestic tap waters were taken from 22 out of 44 AK-diagnosed patient's homes. Microscopic examination, culture, PCR, real-time PCR and DNA sequencing analyses were used for AK-diagnosed samples. The real-time PCR was the most sensitive (100 %) one among the methods used in diagnosis of AK. The 44 (19.0 %) out of 231 corneal scrapings, 4/4 (100 %) contact lens solution and 11/22 (50 %) of domestic tap water samples were found to be positive by real-time PCR for Acanthamoeba. A. griffini (T3), A. castellanii (T4) and A. jacobsi (T15) genotypes were obtained from corneal scrapings, contact lens solutions and domestic tap water samples taken from the patient's homes diagnosed with AK. The isolation of Acanthamoeba containing 6/22 (27.3 %) A. griffini (T3), 14/22 (63.6 %) A. castellanii (T4) and 2/22 (9.1 %) A. jacobsi (T15) from the domestic tap water outlets of 22 of 44 (50 %) of patient's homes revealed that is a significant source of these organisms. A. griffini (T3) and A. jacobsi (T15) genotypes have not been determined from AK cases in Turkey previously. Thus, we conclude that Acanthamoeba keratitis is associated with exposition of patients who has ocular trauma or ocular surface disease to domestic tap water in endemic or potentially endemic countries. PMID:26017346

  7. Distribution and composition of fahs in surface waters, porewater and sediments from Xiamen Western Bay

    NASA Astrophysics Data System (ADS)

    Khalid, Maskaoui; Hong, Hua-Sheng; Zhang, Zu-Lin; Chen, Wei-Qi; Zhou, Jun-Liang

    2001-03-01

    Xiamen Westem Bay's water and sediment quality were studied by determining the levels of sixteen polycyclic aromatic hydrocarbons (PAHs) in water, porewater and sediment samples from nine locations in the bay. Total PAH concentrations varied from 106 to 945 ng/l in water, below detection to 3548 ng/l in porewater, and 247 to 480 ng/g dry weight in surface sediments. PAHs levels in porewater were higher than those in surface water, due to the preference of these hydrophobic compounds for sedimentary phase instead of water. Such a concentration gradient implies a potential flux of pollutants from sediments to overlying water. The PAHs levels in sediments were one to several orders of magnitude lower than those in 1993, suggesting their decreased input in recent years and possible degradation with time.

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

    PubMed Central

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

    1998-01-01

    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 23C 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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aims: The focus of this work was to observe the response of water column and sediment coliform population to the change in nutrient concentrations in the water column. Methods and Results: The survival experiments were conducted in flow-through chambers containing sandy sediments. Bovine faeces wer...

  10. The domestication of water: water management in the ancient world and its prehistoric origins in the Jordan Valley.

    PubMed

    Mithen, Steven

    2010-11-28

    The ancient civilizations were dependent upon sophisticated systems of water management. The hydraulic engineering works found in ancient Angkor (ninth to thirteenth century AD), the Aztec city of Tenochtitlan (thirteenth to fifteenth century AD), Byzantine Constantinople (fourth to sixth century AD) and Nabatean Petra (sixth century BC to AD 106) are particularly striking because each of these is in localities of the world that are once again facing a water crisis. Without water management, such ancient cities would never have emerged, nor would the urban communities and towns from which they developed. Indeed, the 'domestication' of water marked a key turning point in the cultural trajectory of each region of the world where state societies developed. This is illustrated by examining the prehistory of water management in the Jordan Valley, identifying the later Neolithic (approx. 8300-6500 years ago) as a key period when significant investment in water management occurred, laying the foundation for the development of the first urban communities of the Early Bronze Age. PMID:20956370

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

    USGS Publications Warehouse

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

    1964-01-01

    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

  12. Relationship between mineral content of domestic hot water and microbial contamination.

    PubMed

    Borella, Paola; Montagna, M Teresa; Romano-Spica, Vincenzo; Stampi, Serena; Stancanelli, Giovanna; Triassi, Maria; Marchesi, Isabella; Bargellini, Annalisa; Neglia, Rachele; Paglionico, Natalia; Spilotros, Giovanna; Moscato, Umberto; Casati, Giulia; Legnani, Pier Paolo; Sacchetti, Rossella; Ossi, Cristina; Moro, Matteo; Ribera, Gabriella

    2003-01-01

    The relationship between Legionella and Pseudomonas spp contamination and mineral content of domestic hot waters was investigated in a cross-sectional Italian survey. Pseudomonas spp contamination was associated with elevated Ca, but lower Fe and free chlorine content in the water. Waters with Cu concentrations > 50 microg/L prevented Legionella spp colonisation (OR = 0.14, 95% CI = 0.02-1.13), whereas the risk of legionellae occurrence increased in waters with Mn levels > 3 microg/L (OR = 2.37, 95% CI = 1.06-5.30). Furthermore, Mn was positively associated with the risk of colonisation by eterotrophic bacteria growing at either 22 and 36 degrees C. Legionella species and serogroups were differently distributed according to Cu and Mn concentrations, suggesting that Legionella strains may have a different sensibility/resistance to trace elements. A specific action of Cu as decontamination factor is suggested and the consideration of Mn as a risk indicator for bacterial colonisation and biofilm presence is proposed. PMID:14650627

  13. Design, Simulation, and Analysis of Domestic Solar Water Heating Systems in Phoenix, Arizona

    NASA Astrophysics Data System (ADS)

    De Fresart, Edouard Thomas

    Research was conducted to quantify the energy and cost savings of two different domestic solar water heating systems compared to an all-electric water heater for a four-person household in Phoenix, Arizona. The knowledge gained from this research will enable utilities to better align incentives and consumers to make more informed decisions prior to purchasing a solar water heater. Daily energy and temperature data were collected in a controlled, closed environment lab. Three mathematical models were designed in TRNSYS 17, a transient system simulation tool. The data from the lab were used to validate the TRNSYS models, and the TRNSYS results were used to project annual cost and energy savings for the solar water heaters. The projected energy savings for a four-person household in Phoenix, Arizona are 80% when using the SunEarthRTM system with an insulated and glazed flat-plate collector, and 49% when using the FAFCO RTM system with unglazed, non-insulated flat-plate collectors. Utilizing all available federal, state, and utility incentives, a consumer could expect to recoup his or her investment after the fifth year if purchasing a SunEarth RTM system, and after the eighth year if purchasing a FAFCO RTM system. Over the 20-year analysis period, a consumer could expect to save 2,519 with the SunEarthRTM system, and 971 with the FAFCORTM system.

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

    NASA Technical Reports Server (NTRS)

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

    1975-01-01

    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.

  15. Integration of Pseudomonas aeruginosa and Legionella pneumophila in drinking water biofilms grown on domestic plumbing materials.

    PubMed

    Moritz, Miriam M; Flemming, Hans-Curt; Wingender, Jost

    2010-06-01

    Drinking water biofilms were grown on coupons of plumbing materials, including ethylene-propylene-diene-monomer (EPDM) rubber, silane cross-linked polyethylene (PE-X b), electron-ray cross-linked PE (PE-X c) and copper under constant flow-through of cold tap water. After 14 days, the biofilms were spiked with Pseudomonas aeruginosa, Legionella pneumophila and Enterobacter nimipressuralis (10(6) cells/mL each). The test bacteria were environmental isolates from contamination events in drinking water systems. After static incubation for 24 h, water flow was resumed and continued for 4 weeks. Total cell count and heterotrophic plate count (HPC) of biofilms were monitored, and P. aeruginosa, L. pneumophila and E. nimipressuralis were quantified, using standard culture-based methods or culture-independent fluorescence in situ hybridization (FISH). After 14 days total cell counts and HPC values were highest on EPDM followed by the plastic materials and copper. P. aeruginosa and L. pneumophila became incorporated into drinking water biofilms and were capable to persist in biofilms on EPDM and PE-X materials for several weeks, while copper biofilms were colonized only by L. pneumophila in low culturable numbers. E. nimipressuralis was not detected in any of the biofilms. Application of the FISH method often yielded orders of magnitude higher levels of P. aeruginosa and L. pneumophila than culture methods. These observations indicate that drinking water biofilms grown under cold water conditions on domestic plumbing materials, especially EPDM and PE-X in the present study, can be a reservoir for P. aeruginosa and L. pneumophila that persist in these habitats mostly in a viable but non-culturable state. PMID:20556878

  16. An investigation of photovoltaic powered pumps in direct solar domestic hot water systems

    SciTech Connect

    Al-Ibrahim, A.M.; Klein, S.A.; Mitchell, J.W.; Beckman, W.A.

    1996-11-01

    The performance of photovoltaic powered pumps in direct solar domestic hot water (PV-SDHW) systems has been studied. The direct PV-SDHW system employs a photovoltaic array, a separately excited DC-motor, a centrifugal pump, a thermal collector, and a storage tank. A search methodology for an optimum PV-SDHW system configuration has been proposed. A comparison is made between the long-term performance of a PV-SDHW system and a conventional SDHW system operating under three control schemes. The three schemes are: an ON-OFF flow controlled SDHW system operating at the manufacturer-recommended constant flow rate, and ON-OFF flow controlled SDHW system operating at the optimum constant flow rate, and a linear proportional flow controlled SDHW system with the flow proportional to the solar radiation operating under an optimum proportionality.

  17. An investigation of photovoltaic powered pumps in direct solar domestic hot water systems

    SciTech Connect

    Al-Ibrahim, A.M.; Klein, S.A.; Mitchell, J.W.; Beckman, W.A.

    1996-09-01

    The performance of photovoltaic powered pumps in direct solar domestic hot water (PV-SDHW) systems has been studied. The direct PV- SDHW system employs a photovoltaic array, a separately excited DC- motor, a centrifugal pump, a thermal collector, and a storage tank. A search methodology for an optimum PV-SDHW system configuration has been proposed. A comparison is made between the long-term performance of a PV-SDHW system and a conventional SDHW system operating under three control schemes. The three schemes are: an ON-OFF flow controlled SDHW system operating at the manufacturer-recommended constant flow rate, and a linear proportional flow controlled SDHW system with the flow proportional to the solar radiation operating under an optimum proportionality. 13 refs., 6 figs.

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

    SciTech Connect

    Dennehy, G

    1983-04-01

    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.

  19. 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....

  20. 30 CFR 77.216-4 - Water, sediment or slurry impoundments and impounding structures; reporting requirements...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Water, sediment or slurry impoundments and... MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY....216-4 Water, sediment or slurry impoundments and impounding structures; reporting...

  1. 30 CFR 77.216-4 - Water, sediment or slurry impoundments and impounding structures; reporting requirements...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Water, sediment or slurry impoundments and... MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY....216-4 Water, sediment or slurry impoundments and impounding structures; reporting...

  2. Modeling sedimentation-filtration basins for urban watersheds using Soil and Water Assessment Tool

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sedimentation-filtration (SedFil) basins are one of the storm-water best management practices (BMPs) that are intended to mitigate water quality problems in urban creeks and rivers. A new physically based model of variably saturated flows was developed for simulating flow and sediment in SedFils wi...

  3. Survey of the mutagenicity of surface water, sediments, and drinking water from the Penobscot Indian Nation.

    PubMed

    Warren, Sarah H; Claxton, Larry D; Diliberto, Janet; Hughes, Thomas J; Swank, Adam; Kusnierz, Daniel H; Marshall, Valerie; DeMarini, David M

    2015-02-01

    U.S. Environmental Protection Agency (US EPA) Regional Applied Research Effort (RARE) projects address the effects of environmental pollutants in a particular region on the health of the population in that region. This report is part of a RARE project that addresses this for the Penobscot Indian Nation (PIN), Penobscot Island, Maine, U.S., where the Penobscot River has had fish advisories for many years due to high levels of mercury. We used the Salmonella mutagenicity assay with strains TA100, TA98, YG1041, and YG1042 with and without metabolic activation to assess the mutagenic potencies of organic extracts of the Penobscot River water and sediment, as well as drinking-water samples, all collected by the PIN Department of Natural Resources. The source water for the PIN drinking water is gravel-packed groundwater wells adjacent to the Penobscot River. Most samples of all extracts were either not mutagenic or had low to moderate mutagenic potencies. The average mutagenic potencies (revertants/L-equivalent) were 337 for the drinking-water extracts and 177 for the river-water extracts; the average mutagenic potency for the river-sediment extracts was 244 revertants(g-equivalent)(-1). This part of the RARE project showed that extracts of the Penobscot River water and sediments and Penobscot drinking water have little to no mutagenic activity that might be due to the classes of compounds that the Salmonella mutagenicity assay detects, such as polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs (nitroarenes), and aromatic amines. This study is the first to examine the mutagenicity of environmental samples from a tribal nation in the U.S. PMID:25462314

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

    PubMed

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

    2015-03-01

    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

  5. Assessment of water systems for contaminants from domestic and industrial sewages.

    PubMed

    Jordo, C P; Pereira, M G; Bellato, C R; Pereira, J L; Matos, A T

    2002-10-01

    The State of Minas Gerais represents one of Brazil's most outstanding mining resources. The contamination of river water from kaolin processing activities may be harmful to people in the way of slow but chronic poisoning. On the other hand, the discharge of untreated or inadequately treated domestic sewage into aquatic environments can also cause deleterious effects to the health. However, no reliable figures are available for pollutant occurrences in river water. This draws attention to the very precarious situation that exists with respect to pollution by organic and inorganic toxic wastes, especially with respect to humans and fauna in all its expressions. Thus, with the purpose of establishing a preliminary report to trace out industrialisation outcomes, samples of river water, vegetation and fish were collected and analysed to detect pollutant inputs. The concentration of metals was determined in suspended particle, vegetation and fish, while those of nitrite, nitrate, phosphate and chloride were determined in river water samples. The concentration of dissolved oxygen (DO) was measured in river water at the time of collection. Chemical oxygen demand (COD) and biochemical oxygen demand (BOD) were also determined. Metal inputs in the samples analysed appeared to be related to effluent discharges into the rivers. The suspended particles showed high concentrations (in mg kg(-1)) of zinc (62 600) and aluminium (559 000), while vegetation samples collected near rivers were heavily contaminated with iron (7680). The fishes examined were contaminated with chromium (1.5 mg kg(-1)). In general, the concentrations of nitrite, nitrate, chloride, phosphate and BOD in river water were lower than the maximum values established by the Brazilian Environmental Standards. PMID:12381024

  6. Water and stream-sediment sampling techniques for use in uranium exploration

    USGS Publications Warehouse

    Wenrich-Verbeek, Karen J.

    1976-01-01

    Methods of sampling water and stream sediments for uranium were established in this study. Water samples should be taken using a US DH-48 water sampler across the stream channel and should be filtered and acidified in situ. Stream sediments should be taken as a composite sample up and across the axis of the channel. Only sediment fractions less than 90 ?m (170 mesh) should be analyzed for uranium. The elements As, Ca, Al, B, Mg, K, and Na exhibit a positive correlation with uranium in surface waters, while a much larger suite of elements exhibit a positive correlation with uranium in stream sediments: K, Mn, Mg, Ti, Ca, Al, Fe, Pb, Cr, Y, Zr, Li, Zn, Th, and As. Analyses have revealed that anomalies detected in either the dissolved or suspended fractions of water, or the stream sediments, are frequently not reflected in the other two; hence, all three should be sampled and analyzed.

  7. Summary of suspended-sediment concentration data, San Francisco Bay, California, water year 2008

    USGS Publications Warehouse

    Buchanan, Paul A.; Morgan, Tara L.

    2011-01-01

    Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water year 2008 (October 1, 2007September 30, 2008). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun 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 2007 through September 2008. Calibration curves and plots of the processed data for each sensor also are presented.

  8. Summary of Suspended-Sediment Concentration Data, San Francisco Bay, California, Water Year 2007

    USGS Publications Warehouse

    Buchanan, Paul A.; Morgan, Tara L.

    2010-01-01

    Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water year 2007 (October 1, 2006-September 30, 2007). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun 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 2006 through September 2007. Calibration curves and plots of the processed data for each sensor also are presented.

  9. Metal leaching in drinking water domestic distribution system: an Italian case study.

    PubMed

    Sorlini, Sabrina; Gialdini, Francesca; Collivignarelli, Carlo

    2014-01-01

    The objective of this study was to evaluate metal contamination of tap water in seven public buildings in Brescia (Italy). Two monitoring periods were performed using three different sampling methods (overnight stagnation, 30-min stagnation, and random daytime). The results show that the water parameters exceeding the international standards (Directive 98/83/EC) at the tap were lead (max = 363??g/L), nickel (max = 184??g/L), zinc (max = 4900??g/L), and iron (max = 393??g/L). Compared to the total number of tap water samples analyzed (122), the values higher than limits of Directive 98/83/EC were 17% for lead, 11% for nickel, 14% for zinc, and 7% for iron. Three buildings exceeded iron standard while five buildings exceeded the standard for nickel, lead, and zinc. Moreover, there is no evident correlation between the leaching of contaminants in the domestic distribution system and the age of the pipes while a significant influence is shown by the sampling methods. PMID:24382119

  10. Identification of Naegleria fowleri in Domestic Water Sources by Nested PCR

    PubMed Central

    Marciano-Cabral, Francine; MacLean, Rebecca; Mensah, Alex; LaPat-Polasko, Laurie

    2003-01-01

    The free-living amoeboflagellate Naegleria fowleri is the causative agent of primary amoebic meningoencephalitis (PAM), a rapidly fatal disease of the central nervous system. In the United States, the disease is generally acquired while swimming and diving in freshwater lakes and ponds. In addition to swimming, exposure to N. fowleri and the associated disease can occur by total submersion in bathwater or small backyard wading pools. In the present study, swipe samples and residual pipe water from homes in Arizona were examined for N. fowleri by nested PCR due to the death of two previously healthy children from PAM. Since neither child had a history of swimming in a freshwater lake or pond prior to the onset of disease symptoms, the domestic water supply was the suspected source of infection. Of 19 samples collected from bathroom and kitchen pipes and sink traps, 17 samples were positive for N. fowleri by PCR. A sample from a Micro-Wynd II filter was obtained by passing water from bathtubs through the filter. Organisms attached to the filter also tested positive by PCR. The two samples that tested negative for N. fowleri were one that was obtained from a kitchen sink trap and a swipe sample from the garbage disposal of one home. PMID:14532037

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

    PubMed

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

    2013-01-01

    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

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

    NASA Astrophysics Data System (ADS)

    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

    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.

  13. [Controlling effect of coagulation and sedimentation on naidid in water treatment process].

    PubMed

    Huang, Ting-Lin; Zhang, Shuang; Nie, Xiao-Bao; Zhang, Jin-Song; Chen, Hui; Ding, Li-Jun; Liu, Li-Jun

    2011-09-01

    To control naidid pollution in water treatment conducted by O3-BAC, the removal effects of coagulation and sedimentation to naidid were estimated by field sampling of water plant, jar test and simulation study. The results showed that both coagulation and sedimentation of water plant and jar test had obvious removal efficiency on naidids. In the former the mean population density of naidid was decreased from 0. 52 ind/m3 to 0.17 ind/m3, while in the later removal efficiency, which did not be influenced by operation condition of coagulation and sedimentation, reached nearly 100%. Drift migration of naidid from sediment to over-lying water were observed in simulation study and the drift efficiency could be influenced by both temperature and water flow. The drift efficiency of 20 degrees C was 18.5%, much higher than that of 30 degrees C and 10 degrees C. While the velocities of water flow were 2, 4 and 8 mm/s, the number of drifting naidid were 11, 25 and 39 ind respectively. Because of the existence of drift migration, the settlement in sedimentation tank does not mean the real remove of naidid and the thoroughly separating of naidid from water treatment process can only be realized by sludge discharge of sedimentation tank. The naidid removal efficiency of coagulation and sedimentation can be increased by optimizing sludge discharge and restraining drift migration of naidid in sedimentation tank. PMID:22165216

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

    NASA Astrophysics Data System (ADS)

    Kuwabara, James S.; van Geen, Alexander; McCorkle, Daniel C.; Bernhard, Joan M.

    1999-08-01

    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 (<0.5 cm) pore-water sulfide concentrations: <0.008, 0.01, 0.02, to as much as 0.4 ?M at the 340, 430, 550, and 590 m sites, respectively. At a core depth of 10 cm, however, pore-water sulfides exhibited an even wider range: 0.005, 0.05, 0.1, and 100 ?M at the same sites, respectively. The sulfide flux into the deep basin, estimated from water-column profiles during three cruises, suggests a fairly consistent input of 100-300 nmole m -2 h -1. In contrast, sulfide fluxes estimated from pore-water sulfide gradients at the sediment water interface were much more variable (-4 to 13,000 nmole m -2 h -1). Dissolved silicate profiles show clear indications of irrigation at shallow sites (340 and 430 m) in comparison to deeper basin sites (550 and 590 m) with low (<10 ?M) bottom-water dissolved-oxygen concentrations. Pore-water profiles indicate ammonia generation at all sites, but particularly at the deep-basin 590 m site with concentrations increasing with sediment depth to >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.

  15. Occurrence and distribution pattern of acidic pharmaceuticals in surface water, wastewater, and sediment of the Msunduzi River, Kwazulu-Natal, South Africa.

    PubMed

    Agunbiade, Foluso O; Moodley, Brenda

    2016-01-01

    The paucity of information on the occurrence of pharmaceuticals in the environment in African countries led the authors to investigate 8 acidic pharmaceuticals (4 antipyretics, 3 antibiotics, and 1 lipid regulator) in wastewater, surface water, and sediments from the Msunduzi River in the province of KwaZulu-Natal, South Africa, using solid-phase extraction (SPE) and liquid chromatography-mass spectrometry (LC/MS). The method recoveries, limits of detection (LOD), and limits of quantification were determined. The method recoveries were 58.4% to 103%, and the LODs ranged between 1.16?ng/L and 29.1?ng/L for water and between 0.58?ng/g and 14.5?ng/g for sediment. The drugs were all present in wastewater and in most of the surface water and sediment samples. Aspirin was the most abundant pharmaceutical observed, 118??0.82??g/L in wastewater influent, and the most observed antibiotic was nalidixic acid (25.2-29.9??g/L in wastewater); bezafibrate was the least observed. The distribution pattern of the antipyretic in water indicates more impact in suburban sites. The solid-liquid partitioning of the pharmaceuticals between sediment and water, measured as the distribution coefficient (log?KD ) gave an average accumulation magnitude of 10 to 32 in sediments than in water. The downstream distribution patterns for both water and sediment indicate discharge contributions from wastewater, agricultural activities, domestic waste disposal, and possible sewer system leakages. Although concentrations of the pharmaceuticals were comparable with those obtained from some other countries, the contamination of the present study site with pharmaceuticals has been over time and continues at present, making effective management and control necessary. Environ Toxicol Chem 2016;35:36-46. 2015 SETAC. PMID:26138880

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

    USGS Publications Warehouse

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

    2009-01-01

    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.

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

    SciTech Connect

    Ueda, T.; Nugraha, C.; Matsui, K.; Shimada, H.; Ichinose, M.; Gottfried, J.

    2005-07-01

    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.

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

    SciTech Connect

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

    1985-02-01

    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.

  19. Increased Power in Sediment Microbial Fuel Cell: Facilitated Mass Transfer via a Water-Layer Anode Embedded in Sediment

    PubMed Central

    Lee, Yoo Seok; An, Junyeong; Kim, Bongkyu; Park, HyunJun; Kim, Jisu; Chang, In Seop

    2015-01-01

    We report a methodology for enhancing the mass transfer at the anode electrode of sediment microbial fuel cells (SMFCs), by employing a fabric baffle to create a separate water-layer for installing the anode electrode in sediment. The maximum power in an SMFC with the anode installed in the separate water-layer (SMFC-wFB) was improved by factor of 6.6 compared to an SMFC having the anode embedded in the sediment (SMFC-woFB). The maximum current density in the SMFC-wFB was also 3.9 times higher (220.46 mA/m2) than for the SMFC-woFB. We found that the increased performance in the SMFC-wFB was due to the improved mass transfer rate of organic matter obtained by employing the water-layer during anode installation in the sediment layer. Acetate injection tests revealed that the SMFC-wFB could be applied to natural water bodies in which there is frequent organic contamination, based on the acetate flux from the cathode to the anode. PMID:26714176

  20. Increased Power in Sediment Microbial Fuel Cell: Facilitated Mass Transfer via a Water-Layer Anode Embedded in Sediment.

    PubMed

    Lee, Yoo Seok; An, Junyeong; Kim, Bongkyu; Park, HyunJun; Kim, Jisu; Chang, In Seop

    2015-01-01

    We report a methodology for enhancing the mass transfer at the anode electrode of sediment microbial fuel cells (SMFCs), by employing a fabric baffle to create a separate water-layer for installing the anode electrode in sediment. The maximum power in an SMFC with the anode installed in the separate water-layer (SMFC-wFB) was improved by factor of 6.6 compared to an SMFC having the anode embedded in the sediment (SMFC-woFB). The maximum current density in the SMFC-wFB was also 3.9 times higher (220.46 mA/m2) than for the SMFC-woFB. We found that the increased performance in the SMFC-wFB was due to the improved mass transfer rate of organic matter obtained by employing the water-layer during anode installation in the sediment layer. Acetate injection tests revealed that the SMFC-wFB could be applied to natural water bodies in which there is frequent organic contamination, based on the acetate flux from the cathode to the anode. PMID:26714176

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

    EPA Science Inventory

    Diagenetic processes are important drivers of water column biogeochemistry in coastal areas. For example, sediment oxygen consumption can be a significant contributor to oxygen depletion in hypoxic systems, and sedimentwater nutrient fluxes support primary productivity in ...

  2. High performance in low-flow solar domestic hot water systems

    SciTech Connect

    Dayan, M.

    1997-12-31

    Low-flow solar hot water heating systems employ flow rates on the order of 1/5 to 1/10 of the conventional flow. Low-flow systems are of interest because the reduced flow rate allows smaller diameter tubing, which is less costly to install. Further, low-flow systems result in increased tank stratification. Lower collector inlet temperatures are achieved through stratification and the useful energy produced by the collector is increased. The disadvantage of low-flow systems is the collector heat removal factor decreases with decreasing flow rate. Many solar domestic hot water systems require an auxiliary electric source to operate a pump in order to circulate fluid through the solar collector. A photovoltaic driven pump can be used to replace the standard electrical pump. PV driven pumps provide an ideal means of controlling the flow rate, as pumps will only circulate fluid when there is sufficient radiation. Peak performance was always found to occur when the heat exchanger tank-side flow rate was approximately equal to the average load flow rate. For low collector-side flow rates, a small deviation from the optimum flow rate will dramatically effect system performance.

  3. Chemical characterization of blue stains in domestic fixtures in contact with drinking water.

    PubMed

    Letelier, Mara V; Lagos, Gustavo E; Reyes, Arturo

    2008-04-01

    Bluish green staining in domestic fixtures was observed in three to 9-year-old houses in the city of Talca, located 256 km. south of Santiago, the capital of Chile. The houses contained copper pipes which were exposed to soft well water, with low pH and low buffer capacity. The aim of this paper is to establish the chemical composition of the stains and to determine the conditions by which they were formed. X-ray diffraction analysis of the stains revealed the presence of malachite, a copper compound that caused green coloring in kettles and water boilers. Dioptase, which is deep green in coloring, was identified in a bathtub tile. In one house, where blue stains were found in a toilet bowl, the presence of chrysocolla was suggested by means of X-ray fluorescence. In the field conditions studied it was concluded that the bluish green stains in bathroom home appliances were generated by the precipitation of copper compounds in places were leakages occur. PMID:17574543

  4. [Variation of nitrogen during the high suspended sediments concentration water supply in an artificial shallow lake].

    PubMed

    Chen, You-yuan; Shen, Yu; Yang, Shi-ying

    2013-09-01

    The effect of water quality and suspended sediments in the process of water supply is of an increasing concern recently in an artificial shallow lake. The water supply from the Yellow River to Dongchang Lake happened on April 23rd to 25th, 2012. The synchronous monitoring of flow velocity, suspended sediment concentration, dissolved nitrogen and particulate nitrogen concentration was conducted during the three days in five monitoring sites of the longitudinal profile from inlet to outlet. The spatio-temporal variation of nitrogen and the relationship between nitrogen concentration and suspended sediment concentration was analyzed. Moreover, the analysis of different nitrogen forms in surface water and bottom sediment was also made in the whole lake before and after the water supply. Results showed that the process of water supplement had an obvious effect on flow velocities and suspended sediment concentrations around the inlet area. The influence area was a limited scope. The spatial distribution of nitrogen presented a certain concentration gradient along the flow direction. Around the water inlet, concentrations of all nitrogen forms in water and bottom sediment was higher than those in other lake zones. The amplitude of variation of all nitrogen concentrations in surface water, suspended sediments showed a decreasing trend from water inlet to outlet. And concentrations of total dissolved and particulate nitrogen increased at different ratios after water supply in the lake. Total particulate nitrogen concentration increase was higher. It revealed the water supply of the Yellow River had a great influence on lake water. The dissolved nitrogen was the main nitrogen form in water supply. The ratio of total dissolved nitrogen to particulate nitrogen was 7.3 : 1. Nitrate was the primary form in dissolved nitrogen, and ammonium was the primary form in particulate nitrogen, respectively. The correlation between concentration of suspended sediments and ammonium, total nitrogen were notable during te water supply, the correlation coefficient were 0.868 and 0.876. Ammonium was mainly influenced by water supply and adsorption and precipitation of suspended sediments. However, the concentration of nitrate was not influenced. Organic nitrogen was the main form in bottom sediment. It meant that the Yellow River water and suspended sediments were the input sources of nitrogen to Dongehang Lake. PMID:24288987

  5. Degradation of oxolinic acid and flumequine in aquaculture pond waters and sediments.

    PubMed

    Lai, Hong-Thih; Lin, Jing-Ju

    2009-04-01

    Oxolinic acid (OA) and flumequine (FLU) are two of the quinolone antibiotics (QAs) that are widely used in aquaculture. The purpose of this study was to understand the fates of OA and FLU in waters and sediment slurries from aquaculture ponds in a laboratory experiment. Waters and sediments were sampled from an eel (Anguilla japonica) pond and a shrimp (Penaeus vannamei) pond. The effects of light, microbial activities, and temperature on the degradation of these two QAs were elucidated. Results indicated that light plays a major role in the degradation of OA and FLU in waters and sediment slurries. Under illuminated and non-sterile conditions, the half-lives (t(1/2)) of OA were 2.3-4.8 and 9.5-15.0 days in the waters and sediment slurries, respectively. For FLU, under the same conditions, t(1/2) values were 1.9-2.3 and 3.6-6.4 days, respectively. Photodegradation of OA and FLU was much faster in water than in sediment slurry. In both environments, degradation became very slow or would plateau after only minimal change in the dark. Besides the effect of light, biodegradation had very minor effects on the degradation of the two QAs in the sediment slurries. The only independent biodegradation was found when OA was placed in shrimp pond sediment slurry, but at a much lower rate (t(1/2) of 98.7 days) than in light. Biodegradation of FLU was also found in the eel pond sediment slurry but only through an additional connection with light. Also, re-addition enhanced the degradation of OA in shrimp pond sediment slurry, but slowed the degradation of FLU in the eel pond sediment slurry in the dark. The temperature experiment in this study showed no significant effects on degradation of the two QAs in either pond waters or sediment slurries. PMID:19230954

  6. Interparticle collision of natural sediment grains in water

    USGS Publications Warehouse

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

    2001-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

    Dai, Sheng; Seol, Yongkoo

    2014-06-01

    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.

  8. Removal of hexavalent chromium from estuarine waters by model substrates and natural sediments

    SciTech Connect

    Mayer, L.M.; Schick, L.L.

    1981-12-01

    Chromate removal from waters with a range of salinities (0-32%) was studied by using both model substrates, alumina and kaolinite, and natural estuarine sediments in order to determine possible effects of sediment on dissolved chromate in estuarine systems. The dependence of chromate removal on sediment concentrations (<1 g L/sup -1/) will be ineffective in removing dissolved chromate from the water column, though the reaction will be important in deposited sediments. Chromate removal is more effective in low- than high-salinity regimes. Removal by model substrates decreases monotonically with increasing salinity but shows a peak in the 0.1-1.0% range with estuarine sediments. This latter behavior shows similarity with the salinity dependence of chromate reduction by gallic acid, suggesting reductive adsorption by the estuarine sediments. Naturally occurring levels of phosphate ansilicate show negligible effect on chromate removal.

  9. [Assessment of hazardous chemical substances entering water reservoirs of public and domestic water supply].

    PubMed

    Antonova, V I

    1993-01-01

    The paper gives the evaluation of chemical hazards according to indexes of digestive tract functional state when harmful chemicals enter human body with drinking water and also according to such specific effects as genital, embryotoxic, carcinogenic, allergic and teratogenic ones. The author offers an express method of developing MAC (maximum allowable concentrations) of harmful substances based on reducing the time of chronic experiments with due account of group regulation. PMID:8038963

  10. Septic systems as sources of organic wastewater compounds in domestic drinking water wells in a shallow sand and gravel aquifer.

    PubMed

    Schaider, Laurel A; Ackerman, Janet M; Rudel, Ruthann A

    2016-03-15

    Domestic drinking water wells serve 44 million people in the US and are common globally. They are often located in areas served by onsite wastewater treatment systems, including septic systems, which can be sources of biological and chemical pollutants to groundwater. In this study we tested 20 domestic drinking water wells in a sand and gravel aquifer on Cape Cod, Massachusetts, USA, for 117 organic wastewater compounds (OWCs) and for inorganic markers of septic system impact. We detected 27 OWCs, including 12 pharmaceuticals, five per- and polyfluoroalkyl substances (PFASs), four organophosphate flame retardants, and an artificial sweetener (acesulfame). Maximum concentrations of several PFASs and pharmaceuticals were relatively high compared to public drinking water supplies in the US. The number of detected OWCs and total concentrations of pharmaceuticals and of PFASs were positively correlated with nitrate, boron, and acesulfame and negatively correlated with well depth. These wells were all located in areas served exclusively by onsite wastewater treatment systems, which are likely the main source of the OWCs in these wells, although landfill leachate may also be a source. Our results suggest that current regulations to protect domestic wells from pathogens in septic system discharges do not prevent OWCs from reaching domestic wells, and that nitrate, a commonly measured drinking water contaminant, is a useful screening tool for OWCs in domestic wells. Nitrate concentrations of 1mg/L NO3-N, which are tenfold higher than local background and tenfold lower than the US federal drinking water standard, were associated with wastewater impacts from OWCs in this study. PMID:26822473

  11. Chloride/bromide and chloride/fluoride ratios of domestic sewage effluents and associated contaminated ground water

    SciTech Connect

    Vengosh, A.; Pankratov, I.

    1998-09-01

    To establish geochemical tools for tracing the origin of ground water contamination, the authors examined the variations of Cl/Br and Cl/F (weight) ratios in (1) domestic waste water from the Dan Region Sewage Reclamation Project and from reservoirs in the central coast of Israel; (2) associated contaminated ground water; and (3) pristine ground water from the Mediterranean coastal aquifer of Israel. The data show that supply water, anthropogenic NaCl and fluoridation control the Cl/Br and Cl/F ratios of domestic waste water, and conventional sewage treatment does not affect the anthropogenic inorganic signals. The Cl/Br ratios of ground water contaminated with sewage effluent reflect conservative mixing proportions of sewage and regional ground water components. Sensitivity tests demonstrate that it is possible to detect and distinguish sewage contamination from marine ratios after a sewage contribution of 5 to 15% is mixed with regional ground water. Mixing with Br-enriched fresh water however, would reduce this sensitivity. Since the high Cl/Br signal of sewage effluents is distinguishable from other anthropogenic sources with low Cl/Br ratios and from natural contamination sources, Cl/Br ratios can therefore be a useful inorganic tracer for identification of the origin of contaminated ground water. The Cl/F ratios of sewage-contaminated ground water were higher than those in the original sewage effluent, which suggests retention of fluoride into the aquifer solid phase.

  12. 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)

    March, H.; Hernndez, M.; Saur, D.

    2015-05-01

    The design of water awareness campaigns could benefit from knowledge of the specific characteristics of domestic water use and the factors that may influence certain water consumption habits. This paper investigates water use in 450 households in 10 municipalities of drought-prone Alicante (Spain). We aim to increase knowledge about existing domestic water behaviors and therefore help to improve the design and implementation of future water awareness campaigns and even to consolidate reductions in water use after drought periods. The survey suggests that awareness campaigns should revise their scope and their channels of diffusion on a regular basis. In a more specific way, for the Alicante case we propose policy-oriented recommendations on the scope of action for further reductions.

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

    NASA Astrophysics Data System (ADS)

    Neverre, Nomie; Dumas, Patrice

    2014-05-01

    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.

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

    PubMed

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

    2006-06-01

    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

  15. Non-linear effects on solute transfer between flowing water and a sediment bed.

    PubMed

    Higashino, Makoto; Stefan, Heinz G

    2011-11-15

    A previously developed model of periodic pore water flow in space and time, and associated solute transport in a stream bed of fine sand is extended to coarse sand and fine gravel. The pore water flow immediately below the sediment/water interface becomes intermittently a non-Darcy flow. The periodic pressure and velocity fluctuations considered are induced by near-bed coherent turbulent motions in the stream flow; they penetrate from the sediment/water interface into the sediment pore system and are described by a wave number (?) and a period (T) that are given as functions of the shear velocity (U(?)) between the flowing water and the sediment bed. The stream bed has a flat surface without bed forms. The flow field in the sediment pore system is described by the continuity equation and a resistance law that includes both viscous (Darcy) and non-linear (inertial) effects. Simulation results show that non-linear (inertial) effects near the sediment/water interface increase flow resistance and reduce mean flow velocities. Compared to pure Darcy flow, non-linear (inertial) effects reduce solute exchange rates between overlying water and the sediment bed but only by a moderate amount (less than 50%). Turbulent coherent flow structures in the stream flow enhance solute transfer in the pore system of a stream bed compared to pure molecular diffusion, but by much less than standing surface waves or bed forms. PMID:21978571

  16. Aqueous-, pore-water-, and sediment-phase cadmium: Toxicity relationships for a meiobenthic copepod

    SciTech Connect

    Green, A.S.; Chandler, G.T.; Blood, E.R. . Dept. of Environmental Health Sciences)

    1993-08-01

    Comparative effects of aqueous-, pore-water-, and sediment-phase cadmium on mortality of an infaunal laboratory-cultured copepod, Amphiascus tenuiremis, were determined using acute 96-h bioassays. Experimental design included five cadmium concentrations, three replicates per concentration, and 50 adult copepods per replicate for each of the exposure. Exposures included cadmium solubilized in seawater only, whole sediment, and pore water only. In addition, two whole-sediment bioassays were compared in which pore-water cadmium concentrations were altered experimentally but sediment concentrations remained the same. Results of these experiments showed that for Amphiascus tenuiremis, cadmium is most toxic in the aqueous phase, less toxic in the pore-water phase, and last toxic in the sediment-bound phase. The lowered toxicity of cadmium in the pore water was most likely due to complexation of cadmium with DOC, because concentrations of DOC were six times higher in the pore-water phase than in the aqueous phase. In whole sediments, pore-water-phase cadmium was the primary source of acute toxicity, as sediment-associated cadmium contributed negligible effects.

  17. Mirex incorporation in estuarine animals, sediment, and water, Mississippi Gulf Coast--1972-74.

    PubMed

    de la Cruz, A A; Lue, K Y

    1978-06-01

    Analysis of mirex residues in estaurine animals, sediments, and waters collected from the Mississippi Gulf Coast in 1972-74 showed the following ranges of concentrations: seston, 200-3000 ppb; molluscs, 36-500 ppb; fish, 0-259 ppb; sediment, 3-5ppb; and water, 0-0.01 ppb. These data indicate that mirex in aquatic environments is localized in animal tissues and bottom substrate and that only a negligible amount is incorporated in the water. PMID:704293

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

    PubMed Central

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

    2013-01-01

    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

  19. Isolation and molecular characterization of Acanthamoeba genotypes in recreational and domestic water sources from Jamaica, West Indies.

    PubMed

    Todd, Cheridah D; Reyes-Batlle, María; Piñero, José E; Martínez-Carretero, Enrique; Valladares, Basilio; Streete, Don; Lorenzo-Morales, Jacob; Lindo, John F

    2015-09-01

    Free living amoebae (FLA) are amphizoic protozoa that are ubiquitous in nature. Infection with FLA may result in neurological, ocular and skin infections. Exposure to Acanthamoeba occurs frequently through water contact and knowledge of the presence of the organisms in water sources is important in understanding transmission dynamics. The distribution of Acanthamoeba was studied in recreational and domestic water samples collected from across Jamaica. Morphological assessment and polymerase chain reaction revealed Acanthamoeba spp. isolates in 50.6% (42/83) and 17.3% (14/81) of recreational and domestic water, respectively. Sequencing of the DF3 region of the 18S rDNA resulted in the identification of genotypes T3, T4, T5, T10 and T11 corresponding to Acanthamoeba spp: A. griffini, A. triangularis, A. lenticulata, A. culbertsoni and A. hatchetti. Moreover, T4 was the most frequently isolated genotype in both recreational and domestic water. Thermotolerance and osmotolerance assays indicated that most isolates were potentially pathogenic. This is the first report of T3 and T10 genotypes in the Caribbean and the first report of these Acanthamoeba spp. in Jamaican waters. The study shows that there is potential risk of infection to contact wearers who practise poor lens care. Further, Acanthamoeba should be considered as a cause of neurological infections in Jamaica. PMID:26322776

  20. Status of domestic wastewater management in relation to drinking-water supply in two states of India.

    PubMed

    Pandey, R A; Kaul, S N

    2000-01-01

    In India, supply of drinking water, treatment and disposal of domestic wastewater including faecal matter are managed by local bodies. The existing status of water supply, characteristics of domestic wastewater, modes of collection, treatment and disposal system for sewage and faecal matter in 82 municipalities and 4 municipal corporations were assessed in the States of Bihar and West Bengal in India. Domestic wastewater in the municipal areas is collected and discharged through open kachha (earthen), pucca (cement-concrete) and natural drains and discharged into water courses or disposed on land. Scavenger carriage system for night soil disposal is in-vogue at several places in the surveyed States. Open defecation by the inhabitants in some of the municipalities also occurs. The existing methods of collection, treatment and disposal of sewage impairs the water quality of different water sources. Techno-economically viable remedial measures for providing basic amenities, namely safe drinking-water supply and proper sanitation to the communities of these two States of India are suggested and discussed. PMID:10842846

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

    PubMed Central

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

    2012-01-01

    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

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

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

    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.

  3. Phytoremediation facilitates removal of nitrogen and phosphorus from eutrophicated water and release from sediment.

    PubMed

    Xiang, Wu; Xiao-E, Yang; Rengel, Zed

    2009-10-01

    Phosphorus (P) fractions and the effect of phytoremediation on nitrogen and phosphorus removal from eutrophicated water and release from sediment were investigated in the eco-remediation experiment enclosures installed in the Hua-jia-chi pond (Hangzhou city, Zhejiang province, China). The main P fraction in the sediment was inorganic phosphorus (IP). For the mesotrophic sediments, IP mainly consisted of HCl-extractable P (Ca-P). The annual-average concentration of total nitrogen (TN), total phosphorus (TP) in water and the content of TN, TP in different vertical depth of sediment in the experiment enclosures with hydrophyte were always much lower than those in the control enclosure without hydrophyte and those outside of experiment enclosures. It is suggested that phytoremediation was an effective technology for N and P removal from eutrophicated water and release from sediment. PMID:18841488

  4. Toxicity tests of effluents with marsh plants in water and sediment

    SciTech Connect

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

    1991-01-01

    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).

  5. [Effects of waste water sediments on the levels of heavy metals ion the soil and plants].

    PubMed

    Siniagina, N A; Sul'din, B V; Tumanov, A N; Chetvergov, E V

    2004-01-01

    Field small-plot experiments studied the effects of sediments of waste water from Saransk disposal systems. The content of toxic heavy metals (lead, arsenic, and cadmium) in the waste-water sediments, was shown to be not greater than their maximum permissible concentrations (32, 2, and 10 mg per kg of dried soil, respectively). With the use of waste-water sediments, the content of manganese, copper, tin, nickel, vanadium, beryllium, cobalt, iron, and chromium was found to correspond to their baseline level in the soil and plants. PMID:15141618

  6. Chemical quality of surface waters, and sedimentation in the Grand River drainage basin, North and South Dakota

    USGS Publications Warehouse

    Hembree, Charles Herbert; Krieger, Robert A.; Jordan, Paul Robert

    1964-01-01

    An investigation of the chemical quality of surface waters and of the sedimentation in the Grand River drainage basin by the U.S. Geological Survey began in 1946. The chemical quality of the water was studied to obtain information on the nature and amounts of dissolved solids in the streams and on the suitability of the water for domestic, industrial, and irrigation uses. Sedimentation was studied to determine the quantity of sediment that is transported by the streams, the particle sizes of the sediment, and the probable specific weight of the sediment when deposited in a reservoir. The basin is underlain by consolidated sedimentary rocks of Cretaceous and Tertiary age; along the Grand River and its tributaries the rocks are mantled by alluvium of Quaternary age. The Hell Creek and Fort Union Formations underlie about 4,700 of the 5,680 square miles of drainage area. The climate of the basin is semiarid and is characterized by hot summers and cold winters. Mean annual runoff is about 53 acre-feet per square mile of drainage area and is equal to about 7 percent of the mean annual precipitation. The highest streamflows on the Grand River and major tributaries are caused by melting of snow in March and April. Streamflow is extremely variable from year to year. Most of the surface waters in the basin are of the sodium sulfate or sodium bicarbonate type. High percent sodium is typical of almost all the surface waters. The streamflow-quality patterns of the Grand River and its two forks are very similar; dissolved-solids concentration, which usually does not exceed 3,000 ppm, is maximum during low-flow periods. The water in Shadehill Reservoir became stratified during the flood inflow of 1952; about 75 percent of the floodwater, which was of good quality, passed through the reservoir. The quality of the water became almost uniform throughout the reservoir the latter part of July 1952. After the specific conductance became relatively stable in 1956, it fluctuated from about 1,300 to 1,600 micromhos per centimeter and was between 1,400 and 1,500 micromhos per centimeter most of the time. During the representative period July 1937 to June 1950 the quantity of dissolved solids passing the station near Wakpala was estimated to have been about 140,000 tons per year. Yields computed for different parts of the basin ranged from about 22 to 32 tons per square mile. Except for sulfate, concentrations of chemical constituents usually do not exceed the maximum concentrations recommended for domestic supplies. The rather high dissolved solids, and hardness of most of the surface waters prevent the use of these waters for most industrial purposes unless the quality is improved by treatment. Classified for irrigation use according to its specific conductance and sodium-adsorption-ratio, the water stored in Shadehill Reservoir has a high salinity hazard and a medium sodium hazard. The water can be used safely for sustained irrigation on soils of the proposed irrigation unit if adequate leaching is practiced and if gypsum or some other calcium compound is added to the water or land during the high sodium cycle. Suspended-sediment discharges of the Grand River at Shadehill from March 1946 through July 1950 averaged 700,000 tons per year. Suspended-sediment discharges of the South Fork Grand River near Cash for 1947-50, estimated from periodic measurements, averaged 270,000 tons per year. Sediment discharges during these periods were much greater than normal. Suspended-sediment discharges of the North Fork Grand River for 1947-60, estimated from periodic measurements, averaged 31,000 tons per year at Haley and 140,000 tons per year near White Butte. Suspended sediment is predominantly clay ; some silt and a little sand are transported. The probable specific weights of sediment deposits are about 42 pounds per cubic foot for the North and South Forks and 56 pounds per cubic foot for the Grand River at Shadehill. These speci

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

    USGS Publications Warehouse

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

    2009-01-01

    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.

  8. A multi-level pore-water sampler for permeable sediments

    USGS Publications Warehouse

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

    2003-01-01

    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.

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

    USGS Publications Warehouse

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

    1991-01-01

    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.

  10. The transport of fine-grained sediments in shallow waters

    NASA Astrophysics Data System (ADS)

    Ziegler, Carl Kirk; Lick, Wilbert

    1988-02-01

    A numerical model of the resuspension, deposition, and transport of fine-grained, cohesive sediments has been developed and applied. An essential part of this model is an accurate and physically realistic description of the sediment bed and the resuspension of the bottom sediments due to physical processes. The description is based on data from recent experimental and field work on fine-grained sediments. Pertinent results from this work have been incorporated into the present model, and as part of the calculation, changes in the resuspension properties of the sediment bed with time due to resuspension, deposition, and compaction can be approximately determined. Vertically integrated differential equations were used to approximate the hydrodynamic and sediment transport equations. A volume integral method was used to derive finite difference equations which are second-order accurate, explicit, and locally conservative. A unique feature of the numerical model is that it can successfully treat conditions at open boundaries where both incoming and outgoing waves or disturbances may be present. The model has been applied to the resuspension, deposition, and transport of fine-grained sediments in (1) the Raisin River, a small polluted stream flowing into Lake Erie; (2) a river flowing into a lake or ocean with a cross-flow; and (3) a time-dependent flow in a simple estuary as affected by tidal currents. The formation of erosional and depositional areas under various conditions is demonstrated.

  11. 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 ...

  12. 30 CFR 77.216-5 - Water, sediment or slurry impoundments and impounding structures; abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., sediment, or slurry impoundment and impounding structure which meets the requirements of 30 CFR 77.216(a... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Water, sediment or slurry impoundments and impounding structures; abandonment. 77.216-5 Section 77.216-5 Mineral Resources MINE SAFETY AND...

  13. 30 CFR 77.216-5 - Water, sediment or slurry impoundments and impounding structures; abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., sediment, or slurry impoundment and impounding structure which meets the requirements of 30 CFR 77.216(a... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Water, sediment or slurry impoundments and impounding structures; abandonment. 77.216-5 Section 77.216-5 Mineral Resources MINE SAFETY AND...

  14. DEGRATION OF SELECTED HALOGENATED ETHANES IN ANOXIC SEDIMENT-WATER SYSTEMS

    EPA Science Inventory

    The degradation of selected halogenated ethanes was studied in anoxic sediment-water suspensions at 1 to 20% sediment concentrations. Batch kinetic experiments were used to quantify decay. Eh measurements of all suspensions were below -100mV (vs SHE), indicating reduced environme...

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

    USGS Publications Warehouse

    Nowlan, G.A.; Carollo, C.

    1974-01-01

    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.

  16. Variations in Stream Water and Sediment Phosphorus among Select Ozark Catchments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stream sediments play a large role in the transport and fate of soluble reactive phosphorus (SRP) in stream ecosystems, and equilibrium P concentrations (EPC0) of benthic sediments at which P is neither adsorbed or desorbed are often related to stream water SRP concentrations. This study evaluated ...

  17. STUDIES OF BENZIDINE-BASED DYES IN SEDIMENT-WATER SYSTEMS

    EPA Science Inventory

    The sorption and degradation of several benzidine-based dyes were studied in sediment-water systems. tudies in resaturated sediment demonstrated that sorption was strongly dependent on pH and the nature and concentration of the inorganic salt in solution. egradation of the dyes i...

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

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

    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.

  19. 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...

  20. Evaluation of natural radioactivity in soil, sediment and water samples of Niger Delta (Biseni) flood plain lakes, Nigeria.

    PubMed

    Agbalagba, E O; Onoja, R A

    2011-07-01

    This paper presents the findings of a baseline study undertaken to evaluate the natural radioactivity levels in soil, sediment and water samples in four flood plain lakes of the Niger Delta using a hyper pure germanium (HPGe) detector. The activity profile of radionuclides shows low activity across the study area. The mean activity level of the natural radionuclides (226)Ra, (232)Th and (40)K is 203, 203 and 18050Bqkg(-1), respectively. These values are well within values reported elsewhere in the country and in other countries with similar environments. The study also examined some radiation hazard indices. The mean values obtained are, 7614Bqkg(-1), 305.5?Gyh(-1), 376.8?Svy(-1), 0.17 and 0.23 for Radium Equivalent Activity (Ra(eq)), Absorbed Dose Rates (D), Annual Effective Dose Rates (E(ff) Dose), External Hazard Index (H(ex)) and Internal Hazard Index (H(in)) respectively. All the health hazard indices are well below their recommended limits. The soil and sediments from the study area provide no excessive exposures for inhabitants and can be used as construction materials without posing any significant radiological threat to the population. The water is radiologically safe for domestic and industrial use. The paper recommends further studies to estimate internal and external doses from other suspected radiological sources to the population of the Biseni kingdom. PMID:21514983

  1. [Water provision for domestic ducks kept indoors--a review on the basis of the literature and our own experiences].

    PubMed

    Knierim, U; Bulheller, M A; Kuhnt, K; Briese, A; Hartung, J

    2004-03-01

    The wild ancestors of the domestic pekin and muscovy ducks are anatomically, physiologically and behaviourally well adapted to living on and at the water. The domestic ducks kept for fattening purposes still show clear preferences for open water and make use of water for foraging and feeding, drinking, for general exploration, locomotion and preening, even without prior experience. For hygienic, labour, technical and economical reasons ducks are nowadays mostly kept in closed buildings without access to open water. This significantly restricts their freedom to show their natural behaviour. An obvious consequence of this restriction is a deteriorated plumage condition, especially with regard to cleanliness. According to the Council of Europe recommendations, water shall be provided in a way that allows the ducks to cover their head with water and shake it about their body without difficulty. To date, however, there is a lack of solutions satisfying behavioural, hygienic, health, labour and economical requirements to about equally tolerable degrees. The presently available types of different water provisions are presented and discussed on the basis of existing literature as well as experiences and first results from an ongoing research project. The provision of shallow bathing water with daily water exchange promises to be a practicable solution. However, longer term research on possible negative effects of the decreased hygienic quality of the water on duck health is necessary before final conclusions can be drawn. PMID:15195960

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

    NASA Astrophysics Data System (ADS)

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

    2009-04-01

    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.

  3. Domestic water leakage prediction based on a combination of the multi-model approach and classification algorithms

    NASA Astrophysics Data System (ADS)

    Nor Aishah M., N.; Rasmani, Khairul A.; Ismail, Norul Fadhilah; Rashid, Nur Rasyida Mohd; Shahari, N. A.

    2016-02-01

    Combinations of the multi-model have been successfully used to enhance prediction performance, while fuzzy classification techniques have been claimed to be very useful when interpretability of the generated model is very important. In this paper the combination of the multi-model approach with fuzzy classification methods is proposed for the prediction of domestic water leakage, based on consumer data. Selected fuzzy classification techniques were used to induce classification models to predict cases of possible water leakage originally classified as `Likely' or "Unlikely'. Based on analysis conducted using the multi-model approach, the `Likely' cases were reclassified into new classes defined as `Less likely" and `More likely'. Comparison of classification outcomes between the original two-class dataset with the modified three-class dataset show very consistent prediction outcomes. The findings suggest the potential of the combined approach for the prediction of domestic water leakage, based on consumer data.

  4. Low-Cost Solar Domestic Hot Water Systems for Mild Climates

    SciTech Connect

    Burch, J.; Christensen, C.; Merrigan, T.; Hewett, R.; Jorgensen, G.

    2005-01-01

    In FY99, Solar Heating and Lighting set the goal to reduce the life-cycle cost of saved-energy for solar domestic hot water (SDHW) systems in mild climates by 50%, primarily through use of polymer technology. Two industry teams (Davis Energy Group/SunEarth (DEG/SE) and FAFCO) have been developing un-pressurized integral-collector-storage (ICS) systems having load-side heat exchangers, and began field-testing in FY04. DEG/SE?s ICS has a rotomolded tank and thermoformed glazing. Based upon manufacturing issues, costs, and poor performance, the FAFCO team changed direction in late FY04 from an un-pressurized ICS to a direct thermosiphon design based upon use of pool collectors. Support for the teams is being provided for materials testing, modeling, and system testing. New ICS system models have been produced to model the new systems. A new ICS rating procedure for the ICS systems is undergoing testing and validation. Pipe freezing, freeze protection valves, and overheating have been tested and analyzed.

  5. Testing and analysis of load-side immersed heat exchangers for solar domestic hot water systems

    SciTech Connect

    Farrington, R.B.; Bingham, C.E.

    1987-10-01

    This report describes work to determine the performance of load-side heat exchangers for use in residential solar domestic hot water systems. We measured the performance of four heat exchangers: a smooth coil and a finned coil having heat transfer areas of 2.5 m/sup 2/ (26 ft/sup 2/) and those having areas of 1.7 m/sup 2/ (19 ft/sup 2/). A numerical model using the thermal network program MITAS was constructed, and results were compared to the experimental results. Research showed a smooth coil with only 70% of the surface area of a finned coil performed better than the finned coil. Also, load-side heat exchangers can maintain and enhance stratification in storage tanks, permitting the use of control strategies that take advantage of stratified storage tanks to increase system performance. The analytical model, which agreed reasonably well with the experimental results, was used to vary heat exchanger flow rate and area and initial tank temperature for both a smooth- and a finned-coil heat exchanger. Increasing the heat exchanger flow rate and area results in higher heat transfer rates but not necessarily optimal performance. Lower initial tank temperatures resulted in reduced tank stratification. The smooth heat exchanger outperformed the finned heat exchanger with the same outside surface area. 15 refs., 37 figs., 9 tabs.

  6. 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

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

    2011-01-01

    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 μg L-1 in creeks, 0.61–87.0 μg L-1 in WWTP effluents, and 29.3–230 μg g-1 TOC in sediments. Concentrations of COP were 0.09–19.0 μg L-1 in creeks, 0.11–44.0 μg L-1 in WWTP effluents, and 2.51–438 μg 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.

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

    SciTech Connect

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

    1993-12-01

    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.

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

    NASA Astrophysics Data System (ADS)

    Shen, Ping; Zhang, Jing

    2011-12-01

    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.

  9. Effect of overlying water pH, dissolved oxygen, salinity and sediment disturbances on metal release and sequestration from metal contaminated marine sediments.

    PubMed

    Atkinson, Clare A; Jolley, Dianne F; Simpson, Stuart L

    2007-11-01

    Experiments were undertaken to examine the key variables affecting metal release and sequestration processes in marine sediments with metal concentrations in sediments reaching up to 86, 240, 700, and 3000 mg kg(-1) (dry weight) for Cd, Cu, Pb and Zn, respectively. The metal release and sequestration rates were affected to a much greater extent by changes in overlying water pH (5.5-8.0) and sediment disturbance (by physical mixing) than by changes in dissolved oxygen concentration (3-8 mg l(-1)) or salinity (15-45 practical salinity units). The physical disturbance of sediments was also found to release metals more rapidly than biological disturbance (bioturbation). The rate of oxidative precipitation of released iron and manganese increased as pH decreased and appeared to greatly influence the sequestration rate of released lead and zinc. Released metals were sequestered less rapidly in waters with lower dissolved oxygen concentrations. Sediments bioturbated by the benthic bivalve Tellina deltoidalis caused metal release from the pore waters and higher concentrations of iron and manganese in overlying waters than non-bioturbated sediments. During 21-day sediment exposures, T. deltoidalis accumulated significantly higher tissue concentrations of cadmium, lead and zinc from the metal contaminated sediments compared to controls. This study suggests that despite the fact that lead and zinc were most likely bound as sulfide phases in deeper sediments, the metals maintain their bioavailability because of the continued cycling between pore waters and surface sediments due to physical mixing and bioturbation. PMID:17568653

  10. Energy use and domestic hot water consumption - Phase 1. Final report

    SciTech Connect

    Goldner, F.S.

    1994-11-01

    New York State Energy Research & Development Authority has sponsored a project to develop comprehensive operating data on combined domestic hot water (DHW) and heating systems to be used in system design and specifications. The new, more precise DHW flow data (broken down on a per capita basis) result in a better foundation for sizing decisions. Thirty New York City multifamily buildings with combined steam heating and DHW plants were instrumented to monitor apartment, outdoor, boiler and DHW temperatures, and burner on-off times. In nine buildings, which had been upgraded, additional data collected were: stack temperature, DHW flow in 15-minute increments, oil and boiler make-up water flows, and DHW temperature before and after the mixing valve and on the return line. The data set collected for 14 months amounts to a data base of over 110 megabytes. This report presents DHW demand patterns, seasonal variations, weekday vs. weekend consumption, consumption vs. occupancy levels, coincidence of 15-, 60-, 120-, and 180- minute demand periods, and average vs. peak demand levels, as well as figures for energy to generate DHW. The format of guidelines presented in this report differs from those currently in use. The {open_quotes}Low - Medium - High{close_quotes} (LMH) users set of guidelines provide a range, rather than a specific, singular gallonage standard. By providing LMH tables and guidelines for their application the design engineer or contractor can then use these as a tool from which to select the appropriate level that matches the site being served. Values are presented for both New York sizing guidelines (developed from this study), as well as a set of {open_quote}National{close_quote} figures (derived from a compilation of studies conducted in other cities). The LMH approach and {open_quote}National{close_quote} guidelines were adopted for inclusion in the 1995 ASHRAE Handbook revision.

  11. Pore water profiles and early diagenesis of Mn, Cu, and Pb in sediments from large lakes

    SciTech Connect

    McKee, J.D.; Wilson, T.P.; Long, D.T.; Owen, R.M.

    1989-01-01

    Mn, Cu, and Pb were measured in pore waters at a site in the Caribou sub-basin Lake Superior. The pore water profiles show evidence for the post-depositional mobility of the metals, consistent with interpretations made from sediment concentration profiles. The pore water and sediment concentration profiles of Mn appear to be diagenetically linked. Diagenetic modeling results indicate that the measured profiles are not in a steady-state relationship. The cause of the non-steady-state conditions is unclear but may be related to recent changes in sedimentation rates and in Mn/sup 2 +/ oxidation rates. Flux estimates for Cu and Pb show that these metals could be diffusing from the sediment to overlying water. The decomposition or organic matter is suggested as a source for the metals. A significant amount of Cu and Pb brought to the sediment surface during sedimentation appears to be recycled to the pore waters. This suggests that concentration profiles of these metals in the sediment may not be reliable indicators of the timing and amounts of anthropogenic metal input to Lake Superior.

  12. Accumulation of radium in sediments from continued disposal of produced water and hydraulic fracturing flowback water

    NASA Astrophysics Data System (ADS)

    Warner, N. R.; Menio, E. C.; Landis, J. D.; Vengosh, A.; Lauer, N.; Harkness, J.; Kondash, A.

    2014-12-01

    Recent public interest in high volume slickwater hydraulic fracturing (HVHF) has drawn increased interest in wastewater management practices by the public, researchers, industry, and regulators. The management of wastes, including both fluids and solids, poses many engineering challenges, including elevated total dissolved solids and elevated activities of naturally occurring radioactive materials (NORM). One management option for wastewater in particular, which is used in western Pennsylvania, USA, is treatment at centralized waste treatment facilities [1]. Previous studies conducted from 2010-2012 indicated that one centralized facility, the Josephine Brine Treatment facility, removed the majority of radium from produced water and hydraulic fracturing flowback fluid (HFFF) during treatment, but low activities of radium remained in treated effluent and were discharged to surface water [2]. Despite the treatment process and radium reduction, high activities (200 times higher than upstream/background) accumulated in stream sediments at the point of effluent discharge. Here we present new results from sampling conducted at two additional centralized waste treatment facilities (Franklin Brine Treatment and Hart Brine Treatment facilities) and Josephine Brine Treatment facility conducted in June 2014. Preliminary results indicate radium is released to surface water at very low (<50 pCi/L) to non-detectable activities, however; radium continues to accumulate in sediments surrounding the area of effluent release. Combined, the data indicate that 1) radium continues to be released to surface water streams in western Pennsylvania despite oil and gas operators voluntary ban on treatment and disposal of HFFF in centralized waste treatment facilities, 2) radium accumulation in sediments occurred at multiple brine treatment facilities and is not isolated to a single accidental release of contaminants or a single facility. [1] Wilson, J. M. and J. M. VanBriesen (2012). "Oil and Gas Produced Water Management and Surface Drinking Water Sources in Pennsylvania." Environmental Practice 14(04): 288-300. [2] Warner, N. R., C. A. Christie, R. B. Jackson and A. Vengosh (2013). "Impacts of Shale Gas Wastewater Disposal on Water Quality in Western Pennsylvania." ES&T 47(20): 11849-11857.

  13. 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 ...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. 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.

  19. VISUALIZING THE RELATIONSHIP OF PBTS IN WATER AND SEDIMENT TO RESIDUES IN FISH

    EPA Science Inventory

    Bioaccumulation of persistent bioaccumulative toxicants (PBTs) in aquatic organisms results from uptake of the chemicals through several different exposure routes associated with water, sediment, and biota. This paper presents an approach for depicting and interpreting bioaccumul...

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

    NASA Astrophysics Data System (ADS)

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

    2014-09-01

    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.

  1. Selenium sediment toxicity thresholds and derivation of water quality criteria for freshwater biota of western streams

    SciTech Connect

    Van Derveer, W.D.; Canton, S.P.

    1997-06-01

    Waterborne and sediment selenium (Se) data, in conjunction with selected physicochemical parameters, were collected from streams of the middle Arkansas River basin, Colorado, USA, to examine the factors affecting sediment Se accumulation in a lotic environment. An empirical model of dissolved-to-sediment Se transfer in western streams, as an interactive function of sediment organic carbon content, was developed and validated. Sediment Se and associated biological effects data were compiled from the literature, to provide an estimate of sediment Se concentration thresholds that have biological effects. Based on this preliminary analysis, sediment Se concentrations of 2.5 {micro}g/g would be a threshold based on predicted effects and concentrations of 4.0 {micro}g/g would be the observed threshold for dish and wildlife toxicity. The dissolved-to-sediment Se transfer model can be used to translate this type of sediment Se toxicity threshold to a site-specific chronic water-quality standard for western streams based on empirically derived sediment total organic carbon values.

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

    USGS Publications Warehouse

    Rosenberry, D.O.; Pitlick, J.

    2009-01-01

    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.

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

    USGS Publications Warehouse

    Broshears, R.E.

    1991-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2014-07-01

    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 μmol 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.

  5. Intersex and alterations in reproductive development of a cichlid, Tilapia guineensis, from a municipal domestic water supply lake (Eleyele) in Southwestern Nigeria.

    PubMed

    Adeogun, Aina O; Ibor, Oju R; Adeduntan, Sherifat D; Arukwe, Augustine

    2016-01-15

    The objectives of this study were to develop and validate biomarker techniques for aquatic environmental monitoring of endocrine disrupting chemicals (EDCs) in Nigeria aquatic ecosystems, using the Eleyele Lake, which is a major source of domestic water supply to Ibadan and its surrounding towns, as a model aquatic environment and Tilapia guineensis, as a model organism. A total of 55 male and 28 female fish were used for this study. No significant difference in condition factor was observed between the sexes. Evaluation of gross gonadal morphology of the sampled fish showed 33% intersex prevalence in the sampled population, of which respective 71 and 29% were males and females, with visible testis and ovary developing alongside phenotypic females and males. Plasma concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH), 11-ketotestosterone (11-KT) and 17?-estradiol (E2) were performed, showing that male fish had significantly higher plasma LH and E2 concentrations, compared to females. Vitellogenin (Vtg) and zona radiata proteins (Zrp) mRNA levels were significantly higher in males, compared to female fish. Contaminant analysis revealed that PCB 81, 123, 138 and 196 were the only PCB congeners detected in sediment and fish muscle (PCB153 in sediment), while dieldrin was the only organochlorine compound (OC) detected in Eleyele sediment. These responses were used in a multivariate analysis, showing that two principal components were extracted and accounted for 74% of total variation in the dataset. The principal component analysis (PCA) showed that male fish variables were positively correlated with PCB congeners 18 and 123, while female fish showed positive correlations with congener 81, 138, 189, 196, indicating sex-specific pattern of association between PCBs concentrations and biomarker expression. In addition, strong positive correlation between male fish and LH, E2, FSH and Vtg was observed, while female fish positively correlated with 11-KT and GSI. These relationships suggest feminization and masculinization of male and female fish, respectively. PMID:26410712

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

    USGS Publications Warehouse

    Goerlitz, D.F.

    1981-01-01

    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.

  7. Reservoir sediments: a sink or source of chemicals at the surface water-groundwater interface.

    PubMed

    Ammar, Rawaa; Kazpard, Vronique; Wazne, Mahmoud; El Samrani, Antoine G; Amacha, Nabil; Saad, Zeinab; Chou, Lei

    2015-09-01

    This study delineates the physical, chemical, and biological effects resulting from anthropogenic and endogenic activities in a sensitive dammed reservoir situated in a semi-arid region. The reservoir is characterized by two major flow regimes: a wet fill hydrologic regime and a dry spill one. A seasonal sampling campaign was carried out over a period of 2 years (2011-2013) where water samples were collected across the water column and from piezometers just outside the perimeter of the reservoir. Similarly, sediments were collected from the corresponding areas beneath the water column. The water samples were analyzed for environmental isotopic ratios, elemental composition, and physical, biological and chemical parameters, whereas the sediment and algal samples were subjected to physical, mineralogical, spectroscopic, and microscopic analyses. This investigation indicated that the dam had resulted in the alteration of the biogeochemical cycle of nutrients as well as the degradation of the sediment and water quality. The hydrological and biogeochemical processes were found to induce vertical downward transport of chemicals towards the fine grained calcareous sediments during the fill mode, whereas the sediments acted as a source of a chemical flux upward through the water column and downward towards the groundwater during the spill mode. The geomorphological characteristics of the reservoir enhanced the strong hydrological connectivity between the surface water and the groundwater where the reservoir responded quickly to natural and anthropogenic changes in the upper watershed. The water and sediments in the sensitive spill mode were of poor quality and should receive more attention due to the potential hazard for the associated hydro-project and the sustainability of the agricultural soil in the long term. Thus, a safe water and sediment management plan should be implemented in order to improve the dam functionality and to safeguard the precious water resources. PMID:26293891

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

    SciTech Connect

    Fusi, T.; Weber, L.J.

    1995-12-31

    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.

  9. Radium isotopes as a tracer of sediment-water column exchange in the North Sea

    NASA Astrophysics Data System (ADS)

    Burt, W. J.; Thomas, H.; Ptsch, J.; Omar, A. M.; Schrum, C.; Daewel, U.; Brenner, H.; Baar, H. J. W.

    2014-08-01

    Sediment-water column exchange plays an important role in coastal biogeochemistry. We utilize short-lived radium isotopes (224Ra and 223Ra) to understand and quantify the dominant processes governing sediment-water column exchange throughout the North Sea. Our comprehensive survey, conducted in September 2011, represents the first of its kind conducted in the North Sea. We find that two main sources regulate surface Ra distributions: minor coastal input from rivers and shallow mudflats and North Sea sediments as the dominant source. Pore waters show 100-fold larger activities than the water column. North Sea sediment characteristics such as porosity and mean grain size, as well as turbulence at the sediment-water interface, are the dominant factors contributing to variability of Ra efflux. Ra inventory and mass balance approaches consistently yield high benthic Ra effluxes in the southern North Sea, driven by strong tidal and wind mixing, which in turn cause high sediment irrigation rates. These results exceed incubation-based Ra flux estimates and the majority of previously reported Ra flux estimates for other regions. Ra-based estimates of benthic alkalinity fluxes compare well to observed values, and the high rates of Ra efflux imply a potentially significant exchange of other products of sedimentary reactions, including carbon and nutrient species. Passive tracer simulations lend strong support to the Ra source attribution and imply seasonal variation in the surface water Ra distribution depending on stratification conditions.

  10. 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...

  11. 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...

  12. Spatial variability of sediment ecotoxicity in a large storm water detention basin.

    PubMed

    Merchan, Carolina Gonzalez; Perrodin, Yves; Barraud, Sylvie; Sbastian, Christel; Becouze-Lareure, Cline; Bazin, Christine; Kouyi, Gislain Lipeme

    2014-04-01

    Detention basins are valuable facilities for urban storm water management, from both the standpoint of flood control and the trapping of pollutants. Studies performed on storm water have shown that suspended solids often constitute the main vector of pollutants (heavy metals, polycyclic aromatic hydrocarbon (PAH), etc.). In order to characterise the ecotoxicity of urban sediments from storm water detention basins, the sediments accumulated over a 6-year period were sampled at five different points through the surface of a large detention basin localised in the east of Lyon, France. A specific ecotoxicological test battery was implemented on the solid phase (raw sediment) and the liquid phase (interstitial water of sediments). The results of the study validated the method formulated for the ecotoxicological characterization of urban sediments. They show that the ecotoxicological effect of the sediments over the basin is heterogeneous and greater in areas often flooded. They also show the relationship between, on one hand, the physical and chemical characteristics of the sediments and, on the other hand, their ecotoxicity. Lastly, they contribute to a better understanding of the dynamics of the pollution close to the bottom of detention basins, which can be useful for improving their design. The results of this research raise particularly the issue of using oil separators on the surface of detention basins. PMID:24243265

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

    PubMed

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

    2015-01-01

    When surface water levels decline, exposed streambed sediments can be mobilized and washed into the water course when subjected to erosive rainfall. In this study, rainfall simulations were conducted over exposed sediments along stream banks at four distinct locations in an agriculturally dominated river basin with the objective of quantifying the potential for contaminant loading from these often overlooked runoff source areas. At each location, simulations were performed at three different sites. Nitrogen, phosphorus, sediment, fecal indicator bacteria, pathogenic bacteria, and microbial source tracking (MST) markers were examined in both prerainfall sediments and rainfall-induced runoff water. Runoff generation and sediment mobilization occurred quickly (10-150 s) after rainfall initiation. Temporal trends in runoff concentrations were highly variable within and between locations. Total runoff event loads were considered large for many pollutants considered. For instance, the maximum observed total phosphorus runoff load was on the order of 1.5 kg ha. Results also demonstrate that runoff from exposed sediments can be a source of pathogenic bacteria. spp. and spp. were present in runoff from one and three locations, respectively. Ruminant MST markers were also present in runoff from two locations, one of which hosted pasturing cattle with stream access. Overall, this study demonstrated that rainfall-induced runoff from exposed streambed sediments can be an important source of surface water pollution. PMID:25602339

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

    PubMed

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

    2014-05-01

    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

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

    PubMed

    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

    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

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

    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

  17. Sediment size distribution and composition in a reservoir affected by severe water level fluctuations.

    PubMed

    López, Pilar; López-Tarazón, José A; Casas-Ruiz, Joan P; Pompeo, Marcelo; Ordoñez, Jaime; Muñoz, Isabel

    2016-01-01

    The reservoir sediments are important sinks for organic carbon (OC), the OC burial being dependent on two opposite processes, deposition and mineralization. Hence factors such as severe water level fluctuations are expected to influence the rate of OC accumulation as they may affect both deposition and mineralization. The Barasona Reservoir has been historically threatened by siltation, whilst the use of water for irrigation involves a drastic decrease of the water level. In this context, we have studied the physical and chemical characteristics (grain size, major and minor elemental compositions, organic and inorganic carbon, and nitrogen) of the recent sediments of the Barasona Reservoir and the relationships among them in order to: a) elucidate the main processes governing OC accumulation, b) evaluate the rate of OC mineralization and c) approach the effect of drought on the sediment characteristics in this system. Our results indicated that Barasona sediments were dominated by fine silts (>60%) and clays (>20%), the mean particle size decreasing from tail to dam. Desiccation increased particle sorting and size distribution became bimodal, but no effect on average size was observed. Attending to the composition, Barasona sediments were very homogeneous with low concentrations of nitrogen (TN) and phosphorus (<1.2 g kg(-1) dw and <0.6 g kg(-1) dw, respectively) and high concentration of OC (≈36 g kg(-1) dw). TN was negatively related to dry weight. Sediment mixing due to drastic changes in water level may have favoured the observed homogeneity of Barasona sediments affecting carbon, major ions and grain size. The high amount of OC deposited in Barasona sediment suggested that the adsorption of OC onto fine particles was more important than in boreal lakes. The rate of oxygen consumption by wet sediment ranged from 2.26 to 3.15 mg O2 m(-2) day(-1), values close to those compiled for Mediterranean running waters. PMID:26105704

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

    PubMed Central

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

    2014-01-01

    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

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

    PubMed

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

    2014-01-01

    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

  20. Responses of wetland plants to effluents in water and sediment

    SciTech Connect

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

    1991-01-01

    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.

  1. Analytical Methods for Measuring Mercury in Water, Sediment and Biota

    SciTech Connect

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

    2012-06-07

    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 1960s, 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."

  2. Metal cycling during sediment early diagenesis in a water reservoir affected by acid mine drainage.

    PubMed

    Torres, E; Ayora, C; Canovas, C R; García-Robledo, E; Galván, L; Sarmiento, A M

    2013-09-01

    The discharge of acid mine drainage (AMD) into a reservoir may seriously affect the water quality. To investigate the metal transfer between the water and the sediment, three cores were collected from the Sancho Reservoir (Iberian Pyrite Belt, SW Spain) during different seasons: turnover event; oxic, stratified period; anoxic and under shallow perennially oxic conditions. The cores were sliced in an oxygen-free atmosphere, after which pore water was extracted by centrifugation and analyzed. A sequential extraction was then applied to the sediments to extract the water-soluble, monosulfide, low crystallinity Fe(III)-oxyhydroxide, crystalline Fe(III)-oxide, organic, pyrite and residual phases. The results showed that, despite the acidic chemistry of the water column (pH<4), the reservoir accumulated a high amount of autochthonous organic matter (up to 12 wt.%). Oxygen was consumed in 1mm of sediment due to organic matter and sulfide oxidation. Below the oxic layer, Fe(III) and sulfate reduction peaks developed concomitantly and the resulting Fe(II) and S(II) were removed as sulfides and probably as S linked to organic matter. During the oxic season, schwertmannite precipitated in the water column and was redissolved in the organic-rich sediment, after which iron and arsenic diffused upwards again to the water column. The flux of precipitates was found to be two orders of magnitude higher than the aqueous one, and therefore the sediment acted as a sink for As and Fe. Trace metals (Cu, Zn, Cd, Pb, Ni, Co) and Al always diffused from the reservoir water and were incorporated into the sediments as sulfides and oxyhydroxides, respectively. In spite of the fact that the benthic fluxes estimated for trace metal and Al were much higher than those reported for lake and marine sediments, they only accounted for less than 10% of their total inventory dissolved in the column water. PMID:23747557

  3. Microbial transformations of arsenic: mobilization from glauconitic sediments to water.

    PubMed

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

    2012-06-01

    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. PMID:22494492

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

    SciTech Connect

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

    1986-01-01

    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.

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

    SciTech Connect

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

    2012-09-13

    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)].

  6. Heavy metal concentrations in water and sediments in Tasik Chini, a freshwater lake, Malaysia.

    PubMed

    Ebrahimpour, Mohammad; Mushrifah, Idris

    2008-06-01

    The purpose of this paper are to determine the concentration of heavy metals namely cadmium (Cd), copper (Cu) and lead (Pb) in water and sediment; and to investigate the effect of sediment pH and sediment organic matter on concentration of cadmium, copper and lead in sediment at oxidation fraction. For this purpose the concentration of heavy metals were measured in water and sediments at 15 sites from Tasik Chini, Peninsular Malaysia. The sequential extraction procedure used in this study was based on defined fractions: exchangeable, acid reduction, oxidation, and residual. The concentration of heavy metals in residual fraction was higher than the other fractions. Among the non-residual fractions, the concentration of heavy metals in organic matter fraction was much higher than other fractions collected from all sampling sites. The pH of the sediment in all sites was acidic. The mean pH ranges from 4.8 to 5.5 with the higher value observed at site 15. Results of organic matter analysis showed that the percentage of organic matter present in sediment samples varies throughout the lake and all sites of sediments were relatively rich in organic matter ranging from 13.0% to 34.2%. The highest mean percentage of organic matter was measured at sampling site 15, with value of 31.78%. PMID:17891467

  7. Arsenic Redistribution Between Sediments and Water Near a Highly Contaminated Source

    SciTech Connect

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

    2005-01-01

    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.

  8. Using multiple combined analytical techniques to characterize water extractable organic nitrogen from Lake Erhai sediment.

    PubMed

    Li, Zhang; Shengrui, Wang; Haichao, Zhao; Yanping, Li; Shouliang, Huo; Weibin, Qian; Yanli, Yang; Jie, Cheng

    2016-01-15

    In this study, UV-vis absorbance, fluorescence, and FT-IR spectroscopy were combined to characterize the components and structure of the water extractable organic nitrogen (WEON) in Lake Erhai sediment. Lake Erhai sediment WEON comprised predominantly high molecular weight WEON, with the fraction with a molecular weight>1kDa accounting for 87.7% of the total. It was mainly composed of humic acid-like substances, with fewer simple aromatic proteins. Large amounts of aliphatic and amide compounds were detected by IR in the sediments. There were more polymerizable aromatic rings and carbonyl, carboxyl, hydroxyl, and ester compounds in the high molecular weight WEON than in the low molecular weight WEON. Additionally, fluorescence regional integration results implied that the ratio PIII+V,n/PI+II+IV,n can be indirectly taken as an indicator for WEON content in Erhai sediments. Furthermore, the composition and structural characteristics of the WEON were found to be closely related with their properties in the sediment. The large amount of aliphatic compounds in the sediment as well as the relatively high humification and aromatic degree in high molecular weight WEON, stabilizes the WEON in Lake Erhai sediment. Compared with other lake sediments of different trophic statues (such as Lake Dianchi, Lake Poyang, Lake Taihu and Lake Donghu), Erhai sediment exhibited a higher degree of humification, which benefited for reducing sediment WEON releasing risk. And it can be regarded as the reason why the nutrient content in Erhai sediment is very high, but its water quality is still good. PMID:26519594

  9. Element transformation rates and fluxes across the sediment-water interface of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Lipka, Marko; Wegwerth, Antje; Dellwig, Olaf; Al-Raei, Abdul M.; Schoster, Frank; Bttcher, Michael E.

    2014-05-01

    Organic matter is mineralized in brackish-marine sediments by microbial activity using predominantly oxygen, sulfate, and metal oxides as electron acceptors. This leads to a reflux of carbon dioxide into the bottom waters. Under anoxic bottom water conditions, sulfate reduction dominates. Under specific conditions, shallow methane may be oxidized. Pore water profiles reflect biogeochemical processes, transformation rates and fluxes of dissolved species across the sediment-water interface. They are controlled by different factors like microbial activity, bottom water redox conditions, and availability of electron acceptors/donors. Microbial activity in the sediment leads to changes in redox conditions, formation of metabolites and may lead to the formation of authigenic minerals. As an example, organic matter mineralization and reduction of iron oxyhydroxides both may lead to the liberation of dissolved phosphate thereby leading to a reflux into the bottom waters. Hypoxic conditions will enhance this process. We present the results of a detailed biogeochemical investigation of interstitial waters from shallow sediments to study the biogeochemical processes in recent sediments and associated element fluxes at the sediment-water-interface in different areas of the Baltic Sea. Pore water and sediment samples were retrieved from short sediment cores that were collected with multicoring devices in key regions of the Baltic Sea. Pore waters were taken in sufficient depth resolution and analyzed for main and trace element concentrations (e.g., Mn, SO4, HS, PO4, DIC) to allow a modelling of steady-state transformation volumetric rates and element fluxes. A quantitative interpretation of vertical concentration profiles in the pore waters was performed using a diffusion-based modelling approach. Element fluxes across the sediment-water interface show for the Baltic Sea a dependence from bottom water redox conditions, sedimentology, organic contents, and formation conditions (e.g., accumulation rates). In selected anoxic basins, gross anaerobic mineralization rates were additionally obtained from core incubations using a S-35 radiotracer. Highest SRR were found here in the top 5-10 cm. Recent support comes from BMBF during FONA-SECOS project.

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

    PubMed

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

    2015-03-15

    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 100 nm 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 60 nm and 70 nm 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

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

    USGS Publications Warehouse

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

    2004-01-01

    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.

  12. Modeling Hydrodynamics, Water Temperature, and Suspended Sediment in Detroit Lake, Oregon

    USGS Publications Warehouse

    Sullivan, Annett B.; Rounds, Stewart A.; Sobieszczyk, Steven; Bragg, Heather M.

    2007-01-01

    Detroit Lake is a large reservoir on the North Santiam River in west-central Oregon. Water temperature and suspended sediment are issues of concern in the river downstream of the reservoir. A CE-QUAL-W2 model was constructed to simulate hydrodynamics, water temperature, total dissolved solids, and suspended sediment in Detroit Lake. The model was calibrated for calendar years 2002 and 2003, and for a period of storm runoff from December 1, 2005, to February 1, 2006. Input data included lake bathymetry, meteorology, reservoir outflows, and tributary inflows, water temperatures, total dissolved solids, and suspended sediment concentrations. Two suspended sediment size groups were modeled: one for suspended sand and silt with particle diameters larger than 2 micrometers, and another for suspended clay with particle diameters less than or equal to 2 micrometers. The model was calibrated using lake stage data, lake profile data, and data from a continuous water-quality monitor on the North Santiam River near Niagara, about 6 kilometers downstream of Detroit Dam. The calibrated model was used to estimate sediment deposition in the reservoir, examine the sources of suspended sediment exiting the reservoir, and examine the effect of the reservoir on downstream water temperatures.

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

    USGS Publications Warehouse

    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

    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).

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

    NASA Technical Reports Server (NTRS)

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

    2000-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2009-12-01

    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

  16. Acclimation of Hydrilla verticillata to sediment anoxia in vegetation restoration in eutrophic waters.

    PubMed

    Wu, Juan; Dai, Yanran; Rui, Shengyang; Cui, Naxin; Zhong, Fei; Cheng, Shuiping

    2015-12-01

    Sediment anoxia generally results from intense organic enrichment and is a limiting factor in the restoration of vegetation in eutrophic waters. To investigate the effect of sediment anoxia on a typical pollution-tolerant submerged macrophyte species, Hydrilla verticillata, and acclimation mechanisms in the plant, a gradient of sediment anoxia was simulated with additions of sucrose to the sediment, which can stimulate increased concentrations of total nitrogen, NH4(+) and Fe in pore water. H. verticillata growth was significantly affected by highly anoxic conditions, as indicated by reduced total biomass in the 0.5 and 1% sucrose treatments. However, slight anoxia (0.1% sucrose addition) promoted growth, and the shoot biomass was 22.64% higher than in the control. In addition to morphologic alterations, H. verticillata showed physiological acclimations to anoxia, including increased anaerobic respiration and changes in carbon and nitrogen metabolism in roots. The soluble protein and soluble carbohydrate contents in roots of the 1% treatment were both significantly higher compared with those in the control. The increase in alcohol dehydrogenase activity and pyruvate content in the roots suggested that H. verticillata has a well-developed capacity for anaerobic fermentation. This study suggests that highly anoxic sediments inhibit the growth of H. verticillata and the species has a degree of tolerance to anoxic conditions. Further in situ investigations should be conducted on the interactions between sediment conditions and macrophytes to comprehensively evaluate the roles of sediment in the restoration of vegetation in eutrophic waters. PMID:26423394

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

    USGS Publications Warehouse

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

    1987-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2010-11-01

    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

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

    PubMed

    Masi, Ana; Campo, Julin; Vzquez-Roig, Pablo; Blasco, Cristina; Pic, Yolanda

    2013-12-15

    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

  20. 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 ...

  1. 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...

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

    USGS Publications Warehouse

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

    2009-01-01

    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.

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

    PubMed

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

    2015-04-15

    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 10 years 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 10 years 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 10 years earlier. Pb and Zn levels in most sediment samples exceeded the Expert Group (EGS) guidelines of 1000 and 5000 mg/kg, respectively. Arsenic concentrations were as high as 6238 mg/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

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

    PubMed Central

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

    2014-01-01

    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

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

    USGS Publications Warehouse

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

    2010-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

    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.

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

    PubMed

    Larsson, Ann I; Purser, Autun

    2011-06-01

    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

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

    PubMed Central

    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

    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 (8780?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

  9. Threshold events in spring discharge: Evidence from sediment and continuous water level measurement

    NASA Astrophysics Data System (ADS)

    Herman, Ellen K.; Toran, Laura; White, William B.

    2008-03-01

    SummaryIn September 2004, three major hurricanes, Frances, Ivan, and Jeanne, traveled up the eastern United States from the Gulf Coast bringing large amounts of rain to Central Pennsylvania. Monitoring equipment in place at Arch Spring, Blair County, PA captured the effects of these storms on the karstic spring flow. Together these storms revealed a quantitative limit for the carrying capacity of the conduit system. Ivan was a much more devastating storm to the area because rain fell on ground already saturated by Frances, but the net stage increase at the spring was greater during the earlier Frances storm, a 74 cm stage increase versus a 54 cm increase. Storm water not transported through the Arch Spring system was diverted into surface channels during these storms. Suspended sediment collected by an automatic sampler during Frances reveals another threshold crossed. Concurrent with increasing stage and high conductance water, maximum sediment concentrations (933 mg/L) exceed previous fluxes by up to an order of magnitude. The timing of the sediment pulse indicates that high sediment concentrations occur not only when the storm water reaches the spring, but also when stored water is being flushed out of the karst spring system. Sediment previously deposited in the conduit system is flushed only when adequate flows occur, indicating that sediment transport in karst is marked by thresholds and is a strongly non-linear process.

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

    SciTech Connect

    Vazquez, G.F.; Enciso, G.; Morales, J.W.; Sharma, V.K.; Nischt, S.L.; Domingo, G.L.

    1999-07-01

    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.

  11. Pore-water and epibenthic exposures in contaminated sediments using embryos of two estuarine fish species

    SciTech Connect

    Jelinski, J.A.; Anderson, S.L.

    1995-12-31

    The authors` objectives were to determine the feasibility of using embryos of two fish species, Menidia beryllina and Atherinops affinis, in estuarine sediment toxicity tests at ambient temperatures and salinities, and to compare pore-water and sediment water interface corer (SWIC) exposure techniques using these same species. The ultimate goal is to determine whether these pore-water and SWIC methods can be used in in situ exposure studies. Sediment samples were collected at both a reference and contaminated site at the Mare Island Naval Shipyard in San Francisco Bay. Pore-water testes were conducted using methods developed in the laboratory, and SWIC tests were conducted using a modification of B. Anderson et al. Salinity and temperature tolerance experiments revealed that M. beryllina embryos can tolerate temperatures between 160 C and 240 C and salinities of 10 ppt to 25 ppt, whereas A. affinis has a temperature range between 160 C and 200 C. Comparisons between pore-water and SWIC exposures at a reference site within MINSY showed no significant difference in hatching success. However, hatching success in SWIC exposures was significantly lower than pore-water exposures at a previously characterized contaminated site. In conclusion, both M. beryllina and A. affinis embryos may be useful for sediment and in situ toxicity testing in estuarine environments. Their wide temperature and salinity tolerances allow for minimal test manipulations, and M. beryllina showed excellent hatching success in reference sediments for both types of exposures.

  12. Sedimentation patterns on a cold-water coral mound off Mauritania

    NASA Astrophysics Data System (ADS)

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

    2014-01-01

    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.

  13. Analysis of pesticides in surface water and sediment from Yolo Bypass, California, 2004-2005

    USGS Publications Warehouse

    Smalling, Kelly L.; Orlando, James L.; Kuivila, Kathryn M.

    2005-01-01

    Inputs to the Yolo Bypass are potential sources of pesticides that could impact critical life stages of native fish. To assess the direct inputs during inundation, pesticide concentrations were analyzed in water, in suspended and bed-sediment samples collected from six source watersheds to the Yolo Bypass, and from three sites within the Bypass in 2004 and 2005. Water samples were collected in February 2004 from the six input sites to the Bypass during the first flood event of the year representing pesticide inputs during high-flow events. Samples were also collected along a transect across the Bypass in early March 2004 and from three sites within the Bypass in the spring of 2004 under low-flow conditions. Low-flow data were used to understand potential pesticide contamination and its effects on native fish if water from these areas were used to flood the Bypass in dry years. To assess loads of pesticides to the Bypass associated with suspended sediments, large-volume water samples were collected during high flows in 2004 and 2005 from three sites, whereas bed sediments were collected from six sites in the fall of 2004 during the dry season. Thirteen current-use pesticides were detected in surface water samples collected during the study. The highest pesticide concentrations detected at the input sites to the Bypass corresponded to the first high-flow event of the year. The highest pesticide concentrations at the two sites sampled within the Bypass during the early spring were detected in mid-April following a major flood event as the water began to subside. The pesticides detected and their concentrations in the surface waters varied by site; however, hexazinone and simazine were detected at all sites and at some of the highest concentrations. Thirteen current-use pesticides and three organochlorine insecticides were detected in bed and suspended sediments collected in 2004 and 2005. The pesticides detected and their concentrations varied by site and sediment sample type. Trifluralin, p,p'-DDE, and p,p'-DDT were highest in the bed sediments, whereas oxyfluorfen and thiobencarb were highest in the suspended sediments. With the exception of the three organochlorine insecticides, suspended sediments had higher pesticide concentrations compared with bed sediments, indicating the potential for pesticide transport throughout the Bypass, especially during high-flow events. Understanding the distribution of pesticides between the water and sediment is needed to assess fate and transport within the Bypass and to evaluate the potential effects on native fish.

  14. 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...

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

    SciTech Connect

    Hammond, D.E.; Berelson, W.M. ); Giordani, P.; Langone, L.; Frignani, M.; Ravaioli, M. )

    1990-01-09

    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.

  16. 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)

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

    2013-02-01

    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.

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

    PubMed

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

    2015-04-01

    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

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

    USGS Publications Warehouse

    Piper, David Z.; Bau, Michael

    2013-01-01

    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.

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

    PubMed

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

    2010-03-01

    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

  20. Acute toxicity screening of reservoir water and sediment. Reservoir vital signs monitoring, 1990

    SciTech Connect

    Moses, J.; Wade, D.C.

    1991-05-01

    Toxicological evaluation of forebay and transition area water column (overlying water) and sediment porewater (interstitial water) samples was initiated during the summer of 1990 as part of TVA`s Reservoir Vital Signs monitoring. Twenty-four stations were identified for study using acute toxicity screening test methods with the freshwater rotifer Brachionus calyciflorus (Rotox{reg_sign}) and light emitting bacteria Photobacterium phosphoreum (Microtox{reg_sign}). No acute toxicity to rotifers was demonstrated in the first series of tests using water column and sediment samples from the locations selected for monitoring. Sediments from three locations indicated some toxicity based on Microtox{reg_sign}, although all EC{sub 50} concentrations were greater than 100 percent sample.

  1. Human and climate impact on global riverine water and sediment fluxes - a distributed analysis

    NASA Astrophysics Data System (ADS)

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

    2013-05-01

    Understanding riverine water and sediment dynamics is an important undertaking for both socially-relevant issues such as agriculture, water security and infrastructure management and for scientific analysis of climate, landscapes, river ecology, oceanography and other disciplines. Providing good quantitative and predictive tools in therefore timely particularly in light of predicted climate and landuse changes. The intensity and dynamics between man-made and climatic factors vary widely across the globe and are therefore hard to predict. Using sophisticated numerical models is therefore warranted. Here we use a distributed global riverine sediment and water discharge model (WBMsed) to simulate human and climate effect on our planet's large rivers.

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

    NASA Technical Reports Server (NTRS)

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

    1981-01-01

    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.

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

    USGS Publications Warehouse

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

    2003-01-01

    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.

  4. Phosphite flux at the sediment-water interface in northern Lake Taihu.

    PubMed

    Qiu, Huimin; Geng, Jinju; Ren, Hongqiang; Xu, Zhaoyi

    2016-02-01

    Phosphite (H2PO3(-), HPO3(2-), +3 valence), a reduced form of phosphorus (P), has been widely detected in water environments. The role of phosphite in the P biogeochemical cycle has not been investigated systematically and quantitative results on phosphite fluxes are lacking. In this study, intact sediment core simulation was employed to measure the flux of phosphite at the sediment-water interface in northern Lake Taihu. Phosphite fluxes (?molm(-)(2)d(-1)) ranged from -38.211.14 to 7.102.18, with an annual average of -4.7210.40. On the whole, phosphite migrated from water into sediment and the sediment was primarily a sink. The highest seasonal negative phosphite fluxes (?molm(-)(2)d(-1)) occurred in winter (-10.4418.63), followed by summer (-8.045.61) and spring (-2.614.17). In autumn, phosphite flux was 2.204.07. Higher annual average negative fluxes of phosphite (?molm(-)(2)d(-1)) appeared in site ZSB (-12.7017.96), which contained the highest content of total soluble P. The average yearly migration of phosphite in Lake Taihu from water to sediment was estimated to be (4.048.88)10(6)moly(-1). The transfer of phosphite from water into sediment usually occurs in winter may due to the season's natural tendency to create more favorable conditions for phosphite biogeochemical reactions. Phosphite fluxes showed significant negative correlations with the original phosphite concentration in water (r=-0.840, p<0.01), as well as organic matter (r=-0.720, p<0.01) and phosphate bound to Ca (Ca-Ps) (r=-0.632, p<0.05) in sediment. These results indicate that microbiological processes and P species bound to Ca may play an important role in the P redox cycle. No significant correlations between phosphite fluxes and dissolved oxygen or oxidation-reduction potential were observed. PMID:26580728

  5. Partitioning of sediment-associated organic matter in agricultural watersheds: controlling parameters and water quality implications

    NASA Astrophysics Data System (ADS)

    Journet, S.; Pellerin, B. A.; Bachand, P. A.; Spencer, R.; Bergamaschi, B. A.; Hernes, P. J.

    2009-12-01

    Sediment-associated organic matter (OM) may constitute a significant source of dissolved organic matter (DOM) in agricultural watersheds, but the partitioning of sediment-bound OM is still poorly characterized in such systems. The Willow Slough agricultural watershed in the Central Valley of California, USA, is the focus of a study of DOM dynamics in agricultural watersheds. Weekly surface water samples collected at the watershed outlet since January 2006 show that dissolved organic carbon (DOC) concentrations increase during summer irrigation up to 7 mg/L, and steadily return to winter baseline concentrations (2 mg/L). A similar trend is observed for total suspended sediment concentrations (TSS), which peak about five weeks earlier than DOC (late June) around 200 mg/L, suggesting that sediments may contribute significantly to the delivery of DOM. We investigated the potential impact of sediment-bound OM partitioning on DOM concentration and composition in agricultural surface waters and will present laboratory data related to the equilibrium abiotic release of DOM from suspended, bed, and bank sediments, collected in the Willow Slough watershed over a range of land uses and hydrologic conditions. Desorption isotherms show distinct DOC contributions between sediment types (from 2 to 15% OC desorbed), with suspended sediment from summer irrigation yielding up to 3.4 times more DOC than winter storm suspended sediment, and 4.8 times more than summer bed sediment. In addition, environmental parameters such as water temperature, conductivity, and pH were found to affect OM partitioning differently, pH displaying the most control on DOC release (up to 60% increase from pH 6.5 to pH 9.5). Finally, a detailed biogeochemical characterization of the desorbed DOM quality (including amino acids composition) will serve as a basis for comparing riverine and sediment-derived DOM. By assessing the contribution of DOM from sediments in agricultural watersheds, this research provides a better understanding of DOM dynamics and composition at the interface between soil and water ecosystems

  6. A new device for collection of interstitial water from wetland sediments

    USGS Publications Warehouse

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

    1992-01-01

    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.

  7. Developing Water Quality Critera for Suspended and Bedded Sediments-Illustrative Example Application.

    EPA Science Inventory

    The U. S. EPA's Framework for Developing Suspended and Bedded Sediments (SABS) Water Quality Criteria (SABS Framework) provides a consistent process, technical methods, and supporting materials to enable resource managers to develop ambient water quality criteria for one of the m...

  8. 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...

  9. 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...

  10. 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...

  11. Methyl t-Butyl Ether Mineralization in Surface-Water Sediment Microcosms under Denitrifying Conditions

    USGS Publications Warehouse

    Bradley, P.M.; Chapelle, F.H.; Landmeyer, J.E.

    2001-01-01

    Mineralization of [U-14C] methyl t-butyl ether (MTBE) to 14CO2 without accumulation of t-butyl alcohol (TBA) was observed in surface-water sediment microcosms under denitrifying conditions. Methanogenic activity and limited transformation of MTBE to TBA were observed in the absence of denitrification. Results indicate that bed sediment microorganisms can effectively degrade MTBE to nontoxic products under denitrifying conditions.

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

    PubMed

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

    2015-01-01

    Sedimentation dynamics of magnetite (γ-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<0.15 cm/s. For particle concentration c=1 g/l, purification of 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

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

    USGS Publications Warehouse

    Bartsch, L.A.; Rada, R.G.; Sullivan, J.F.

    1996-01-01

    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.

  14. Spatial Variability of Metals in Surface Water and Sediment in the Langat River and Geochemical Factors That Influence Their Water-Sediment Interactions

    PubMed Central

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

    2012-01-01

    This paper determines the controlling factors that influence the metals' behavior water-sediment interaction facies and distribution of elemental content (75As, 111Cd, 59Co, 52Cr, 60Ni, and 208Pb) 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 μg/L for As, <0.01–0.53 μg/L for Cd, 0.06–6.22 μg/L for Co, 0.32–4.67 μg/L for Cr, 0.80–24.72 μg/L for Ni, and <0.005–6.99 μg/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

  15. Distribution, sources and composition of antibiotics in sediment, overlying water and pore water from Taihu Lake, China.

    PubMed

    Xu, Jian; Zhang, Yuan; Zhou, Changbo; Guo, Changsheng; Wang, Dingming; Du, Ping; Luo, Yi; Wan, Jun; Meng, Wei

    2014-11-01

    The occurrence of 15 antibiotics classified as sulphonamides, fluoroquinolones, macrolides, tetracyclines and trimethoprim in sediment, overlying water, and pore water matrices in Taihu Lake, China was studied. The total concentrations were from 4.1 ?g/kg to 731 ?g/kg, from 127 ng/L to 1210 ng/L, and from 1.5 ng/L to 216 ng/L in sediment, overlying water and pore water, respectively. Antibiotics in different locations originated from various sources, depending on human, agricultural and aquacultural activities. Composition analysis indicated that human-derived and animal-derived drugs significantly contributed to the total contamination of antibiotics in the lake, indicating the high complexity of contamination sources in Taihu Lake Basin. The in situ sediment-pore water partitioning coefficients were generally greater than sediment-overlying water partitioning coefficients, suggesting continuous inputs into the lake water. This study shows that antibiotics are ubiquitous in all compartments in Taihu Lake, and their potential hazards to the aquatic ecosystem need further investigation. PMID:25129162

  16. Occurrence of ionophore antibiotics in water and sediments of a mixed-landscape watershed.

    PubMed

    Kim, Sung-Chul; Carlson, Kenneth

    2006-07-01

    Analytical methods for quantifying three ionophore antibiotics, monensin, salinomycin, and narasin, were developed for water and sediment matrices. Sample preparation was based on solid-phase extraction (SPE) and high-performance liquid chromatography (HPLC) tandem mass spectrometry (MS/MS) was used to separate and detect the compounds. Recoveries ranged from 83% to 117% for water and from 51% to 105% for sediment in three different concentrations with less than 10% of relative standard deviation. The statistical detection limit was 0.001-0.003 microg/L for water and 0.4-3.6 microg/kg for sediment. Ionophore antibiotics are only used to treat coccidiostats for broilers or turkeys, and to increase growth and feed efficiency for beef and dairy cattle. Since they are not used for human purposes, these compounds can act as markers for the transport of animal pharmaceuticals to the watershed. The occurrence of three ionophore compounds was determined at five sampling sites along the Cache la Poudre River in Northern Colorado representing pristine, urban, and agriculture landscapes. Statistical analysis demonstrates that the measured concentration was significantly different among sampling sites in different sampling events for both water and sediment. In addition, significant differences were observed among different sampling times at each sampling site. Furthermore, all three ionophores were found in the sediments at much higher concentrations than in water indicating the importance of this matrix when determining environmental impacts. PMID:16790258

  17. Microbial Response to Experimentally Controlled Redox Transitions at the Sediment Water Interface.

    PubMed

    Frindte, Katharina; Allgaier, Martin; Grossart, Hans-Peter; Eckert, Werner

    2015-01-01

    The sediment-water interface of freshwater lakes is characterized by sharp chemical gradients, shaped by the interplay between physical, chemical and microbial processes. As dissolved oxygen is depleted in the uppermost sediment, the availability of alternative electron acceptors, e.g. nitrate and sulfate, becomes the limiting factor. We performed a time series experiment in a mesocosm to simulate the transition from aerobic to anaerobic conditions at the sediment-water interface. Our goal was to identify changes in the microbial activity due to redox transitions induced by successive depletion of available electron acceptors. Monitoring critical hydrochemical parameters in the overlying water in conjunction with a new sampling strategy for sediment bacteria enabled us to correlate redox changes in the water to shifts in the active microbial community and the expression of functional genes representing specific redox-dependent microbial processes. Our results show that during several transitions from oxic-heterotrophic condition to sulfate-reducing condition, nitrate-availability and the on-set of sulfate reduction strongly affected the corresponding functional gene expression. There was evidence of anaerobic methane oxidation with NOx. DGGE analysis revealed redox-related changes in microbial activity and expression of functional genes involved in sulfate and nitrite reduction, whereas methanogenesis and methanotrophy showed only minor changes during redox transitions. The combination of high-frequency chemical measurements and molecular methods provide new insights into the temporal dynamics of the interplay between microbial activity and specific redox transitions at the sediment-water interface. PMID:26599000

  18. Heavy metals in Yenia?a Lake and its potential sources: soil, water, sediment, and plankton.

    PubMed

    Sayg?, Yasemin; Yi?it, Sibel Atasagun

    2012-03-01

    The distribution and accumulation of heavy metals (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Mo, Cd, Sn, Ba, Pb) in the water, sediments, plankton of Yenia?a Lake, and its potential sources (creeks, sewage, artesian well, soil) were investigated during 1-year study period as monthly or seasonally. Element analyses were performed by ICP-MS. Results showed that the trace and toxic elements (Al, As, Mn, Pb, Fe) concentration in lake water and/or its feeding sources were above the recommended water standards (WHO, EC, EPA, TS-266). It was found that the maximum accumulation of the heavy metals iron, aluminum, manganese, zinc, and barium in the sediment of Yenia?a Lake. The accumulation order of trace metals were Fe > Al > Mn > Zn > Ba > Ni > Cr > As > Cu > Pb > Co > Mo > Sn > Cd in the lake, creeks sediment, and soil samples. The similar results suggest that the accumulation of heavy metals in the sediment is a natural process. Metals accumulated in the lake are naturally mixed from the soil. However, the presence of heavy metals in the analysis of artesian well water and sewage reveals that the transportation occurs also from the groundwater to the lake. The results obtained in plankton in Yenia?a Lake showed that aluminum, iron, manganese, zinc, and barium were most accumulated elements in the plankton. The lower averages of lead prevalent in the water and sediment during some months were seen to have a significant mean accumulation in the plankton. PMID:21494824

  19. 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, ...

  20. Summary of suspended-sediment concentration data, San Francisco Bay, California, water year 2010

    USGS Publications Warehouse

    Buchanan, Paul A.; Morgan, Tara L.

    2014-01-01

    Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water year 2010 (October 1, 2009September 30, 2010). Turbidity sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, one site in San Pablo Bay, three 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 turbidity sensors so that a record of suspended-sediment concentrations could be computed. This report presents the data-collection methods used and summarizes, in graphs, the suspended-sediment concentration data collected from October 2009 through September 2010. Calibration curves and plots of the processed data for each sensor also are presented.

  1. Summary of suspended-sediment concentration data, San Francisco Bay, California, water year 2009

    USGS Publications Warehouse

    Buchanan, Paul A.; Morgan, Tara L.

    2012-01-01

    Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water year 2009 (October 1, 2008September 30, 2009). 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 2008 through September 2009. Calibration curves and plots of the processed data for each sensor also are presented.

  2. Development of Layered Sediment Structure and its Effects on Pore Water Transport and Hyporheic Exchange

    SciTech Connect

    Packman, Aaron I.; Marion, Andrea; Zaramella, Mattia; Chen, Cheng; Gaillard, Jean-Franois; Keane, Denis T.

    2008-04-15

    Hyporheic exchange is known to provide an important control on nutrient and contaminant fluxes across the stream-subsurface interface. Similar processes also mediate interfacial transport in other permeable sediments. Recent research has focused on understanding the mechanics of these exchange processes and improving estimation of exchange rates in natural systems. While the structure of sediment beds obviously influences pore water flow rates and patterns, little is known about the interplay of typical sedimentary structures, hyporheic exchange, and other transport processes in fluvial/alluvial sediments. Here we discuss several processes that contribute to local-scale sediment heterogeneity and present results that illustrate the interaction of overlying flow conditions, the development of sediment structure, pore water transport, and stream-subsurface exchange. Layered structures are shown to develop at several scales within sediment beds. Surface sampling is used to analyze the development of an armor layer in a sand-and-gravel bed, while innovative synchrotron-based X-ray microtomography is used to observe patterns of grain sorting within sand bedforms. We show that layered bed structures involving coarsening of the bed surface increase interfacial solute flux but produce an effective anisotropy that favors horizontal pore water transport while limiting vertical penetration.

  3. Solar heating, cooling, and domestic hot water system installed at Kaw Valley State Bank and Trust Company, Topeka, Kansas

    NASA Technical Reports Server (NTRS)

    1980-01-01

    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.

  4. Factors controlling the silicon isotope distribution in waters and surface sediments of the Peruvian coastal upwelling

    NASA Astrophysics Data System (ADS)

    Ehlert, Claudia; Grasse, Patricia; Mollier-Vogel, Elfi; Bschen, Tebke; Franz, Jasmin; de Souza, Gregory F.; Reynolds, Ben C.; Stramma, Lothar; Frank, Martin

    2012-12-01

    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 5S and 15S 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.

  5. [Distribution of polycyclic aromatic hydrocarbons in water and sediment from Zhoushan coastal area, China].

    PubMed

    Jiang, Min; Tuan, Le Huy; Mei, Wei-Ping; Ruan, Hui-Hui; Wu, Hao

    2014-07-01

    The spatial and temporal distribution of 16 polycyclic aromatic hydrocarbons (PAHs) has been investigated in water and sediments of Zhoushan coastal area every two months in 2012. The concentrations of total PAHs ranged from 382.3 to 816.9 ng x L(-1), with the mean value of 552.5 ng x L(-1) in water; whereas it ranged from 1017.9 to 3047.1 ng x g(-1), with the mean value of 2 022.4 ng x g(-1) in sediment. Spatial distribution showed that Yangshan and Yanwoshan offshore area had the maximum and minimum of total PAHs contents in water, while the maximum and minimum occurred at Yangshan and Zhujiajian Nansha offshore area in sediment. Temporal distribution revealed that total PAHs contents in water reached the maximum and minimum values in October and June, however in sediments these values were found in August and June, respectively. The PAHs pollution was affected by oil emission, charcoal and coal combustion. Using the biological threshold and exceeded coefficient method to assess the ecological risk of PAHs in Zhoushan coastal area, the result showed that sigma PAHs had a lower probability of potential risk, while there was a higher probability of potential risk for acenaphthylene monomer, and there might be ecological risk for acenaphthene and fluorene. Distribution of PAHs between sediment and water showed that Zhoushan coastal sediment enriched a lot of PAHs, meanwhile the enrichment coefficient (K(d) value) of sediment in Daishan island was larger than that in Zhoushan main island. PMID:25244854

  6. Sediment desiccation as a driver of phosphate availability in the water column of Mediterranean wetlands.

    PubMed

    Gilbert, Juan Diego; Guerrero, Francisco; de Vicente, Inmaculada

    2014-01-01

    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

  7. Comparative studies on extraction of sediment interstitial waters: Discussion and comment on the current state of interstitial water studies

    USGS Publications Warehouse

    Manheim, F. T.

    1974-01-01

    The implication by Murthy and Ferrell (1972)that interstitial water studies are in a confused state is criticized on the basis that the authors have not drawn on a considerable body of data, especially Soviet studies since the 1950's, and results of the Deep Sea Drilling Project. Pressure filtration systems for extracting interstitial waters are currently the methods of choice for marine studies and have achieved substantial reliability and reproducibility. Although gaps and problems remain, many aspects of interstitial composition of marine sediments have been clarified; these include the substantial constancy of composition of interstitial waters in deep sea pelagic deposits, depletion of interstitial cations owing to authigenic mineral formation in more rapidly accumulated (especially terrigenous) sediments, and special phenomena in sediments overlying salt deposits. ?? 1974.

  8. The marine geochemistry of actinium-227: Evidence for its migration through sediment pore water

    SciTech Connect

    Nozaki, Yoshiyuki; Yamada, Masatoshi ); Nikaido, Hirofumi )

    1990-10-01

    {sup 227}Ac with a half life of 21.8 years has a potential utility as a tracer of deep water circulation and mixing studies on time scales less than 100 years. Here the authors present the first measurement of {sup 227}Ac profile in the pore water of Northwest Pacific deep-sea sediment and in the {approximately}10,000 m long water column of Izu-Ogasawara Trench. The results clearly show that {sup 227}Ac is supplied from the sediment to the overlying water through migration in the pore water. The model calculation indicates that the molecular diffusion alone through sediment porewater can support only a half of the standing crop of excess {sup 227}Ac in the water column and the enhanced supply of {sup 227}Ac by particle mixing is necessary to account for the remainder. Thus, bioturbation in the deep sea plays an important role in controlling the flux of some short-lived radionuclides such as {sup 227}Ac and {sup 228}Ra across the sediment-water interface.

  9. Methods for determination of inorganic substances in water and fluvial sediments

    USGS Publications Warehouse

    Fishman, Marvin J., (Edited By); Friedman, Linda C.

    1989-01-01

    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.

  10. Diffusive release of uranium from contaminated sediments into capillary fringe pore water

    SciTech Connect

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

    2012-10-01

    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.

  11. Microbial and chemical contamination of water, sediment and soil in the Nakivubo wetland area in Kampala, Uganda.

    PubMed

    Fuhrimann, Samuel; Stalder, Michelle; Winkler, Mirko S; Niwagaba, Charles B; Babu, Mohammed; Masaba, Godfrey; Kabatereine, Narcis B; Halage, Abdullah A; Schneeberger, Pierre H H; Utzinger, Jürg; Cissé, Guéladio

    2015-07-01

    The reuse of domestic and industrial wastewater in urban settings of the developing world may harm the health of people through direct contact or via contaminated urban agricultural products and drinking water. We assessed chemical and microbial pollutants in 23 sentinel sites along the wastewater and faecal sludge management and reuse chain of Kampala, Uganda. Water samples were examined for bacteria (thermotolerant coliforms (TTCs), Escherichia coli and Salmonella spp.) and helminth eggs. Physico-chemical parameters were determined. Water, sediment and soil samples and edible plants (yams and sugar cane) were tested for heavy metals. Water samples derived from the Nakivubo wetland showed mean concentrations of TTCs of 2.9 × 10(5) colony-forming units (CFU)/100 mL. Mean E. coli was 9.9 × 10(4) CFU/100 mL. Hookworm eggs were found in 13.5% of the water samples. Mean concentrations of iron (Fe), copper (Cu) and cadmium (Cd) were 21.5, 3.3 and 0.14 mg/L, respectively. In soil samples, we found a mean lead (Pb) concentration of 132.7 mg/L. In yams, concentrations of Cd, chromium (Cr) and Pb were 4.4, 4.0 and 0.2 mg/L, while the respective concentrations in sugar cane were 8.4, 4.3 and 0.2 mg/L. TTCs and E. coli in the water, Pb in soil, and Cd, Cr and Pb in the plants were above national thresholds. We conclude that there is considerable environmental pollution in the Nakivubo wetland and the Lake Victoria ecosystem in Kampala. Our findings have important public health implications, and we suggest that a system of sentinel surveillance is being implemented that, in turn, can guide adequate responses. PMID:26122126

  12. Water volume and sediment accumulation in Lake Linganore, Frederick County, Maryland, 2009

    USGS Publications Warehouse

    Sekellick, Andrew J.; Banks, S.L.

    2010-01-01

    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).

  13. Concentration and distribution of antibiotics in water-sediment system of Bosten Lake, Xinjiang.

    PubMed

    Lei, Xiaoning; Lu, Jianjiang; Liu, Zilong; Tong, Yanbin; Li, Shanman

    2015-02-01

    This study investigated the residues of four sulfonamides, four quinolones, and four tetracyclines in surface water as well as surficial sediment samples, of Bosten Lake, in Xinjiang, China. The results showed the presence of 10 out of the 12 selected antibiotics in both water and sediment. Lomefloxacin was not detected in any of the samples. Among the 12 antibiotics considered, ciprofloxacin, with median concentrations of 39.22 ng L(-1) in surface water and 76.51 ?g kg(-1) in surficial sediment, was the dominant antibiotic in all samples. The sorption coefficient values presented higher sorption capacities of tetracycline and chlortetracycline than the other antibiotics. The cluster analysis revealed elevated levels of pollution in sampling sites 1, 2, and 3, which were situated in a nearby urban area and in the estuary of Kaidu River. This study demonstrates the necessity of regulating the use of antibiotics and improving the management and treatment of their release. PMID:24809500

  14. Laboratory upwelled radiance and reflectance spectra of Kerr reservoir sediment waters

    NASA Technical Reports Server (NTRS)

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

    1982-01-01

    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.

  15. Can sediment data be used to predict alkalinity and base cation chemistry of surface waters?

    PubMed

    Begum, S; McClean, C J; Cresser, M S; Breward, N

    2010-12-15

    We hypothesise that stream sediment elemental composition can predict mean and minimum concentrations of alkalinity, Ca and Mg in the river water throughout a river network. We tested this hypothesis for the River Derwent catchment in North Yorkshire, England, by using 6 years of water chemistry data from the Environment Agency and a digital elevation model to flow path-weight British Geological Survey (BGS) sediment element concentration data. The predictive models for mean concentrations were excellent for Ca and alkalinity, but less good for Mg, and did not require land use data inputs as stream water sediment composition seems to reflect all aspects of the riparian zone soil system. Predictive model forms were linear. Attempts to predict minimum values for Ca and alkalinity also were less satisfactory. This probably is due to variations in hydrological response times to individual precipitation events across the catchment. PMID:21051075

  16. QUANTITATIVE VS. CONVENTIONAL PCR FOR DETECTION OF HUMAN ADENOVIRUSES IN WATER AND SEDIMENT SAMPLES

    PubMed Central

    STAGGEMEIER, Rodrigo; BORTOLUZZI, Marina; HECK, Tatiana Moraes da Silva; SPILKI, Fernando Rosado; ALMEIDA, Sabrina Esteves de Matos

    2015-01-01

    SUMMARY Human Adenoviruses (HAdV) are notably resistant in the environment. These agents may serve as effective indicators of fecal contamination, and may act as causative agents of a number of different diseases in human beings. Conventional polymerase chain reaction (PCR) and, more recently, quantitative PCR (qPCR) are widely used for detection of viral agents in environmental matrices. In the present study PCR and SYBR(r)Green qPCR assays were compared for detection of HAdV in water (55) and sediments (20) samples of spring and artesian wells, ponds and streams, collected from dairy farms. By the quantitative methodology HAdV were detected in 87.3% of the water samples and 80% of the sediments, while by the conventional PCR 47.3% and 35% were detected in water samples and sediments, respectively. PMID:26422153

  17. [Indication of Northern Caspian regions by biochemical (enzymatic) indices of water and bottom sediments].

    PubMed

    Korneeva, G A; Miroshnik, L Iu; Tsytsarin, A G

    2003-01-01

    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

  18. Hg bioaccumulation in a contaminated flowing water system-sediment, macroinvertebrates, and fish interactions

    NASA Astrophysics Data System (ADS)

    Pizarro-Barraza, C.; Gustin, M. S.; Peacock, M.

    2010-12-01

    The Truckee River (TR) of Nevada/California USA has been and is impacted physically and chemically by human actions. Previous work has shown a significant difference in mercury (Hg) concentrations of fish and water collected above and below the confluence of Steamboat Creek (SBC) with the river. Steamboat Creek is contaminated with Hg due to legacy milling of gold and silver ore at Washoe Lake. We investigated the potential for Hg concentrations in water, sediments and macroinvertebrates to be latent indicators of potential sources of methylmercury (MeHg) for fish species. Sites below SBC showed significantly higher Hg concentrations in water, sediments, macroinvertebrates, and fish. Not only were MeHg concentrations in sediments associated with specific environmental conditions, but sediments from the shore versus the active channel appeared to be an important source of MeHg to waters during periods of high flow. Data showed that areas with high Hg concentrations in sediments were also locations of elevated Hg concentrations in some species of macroinvertebrates. Bioaccumulation was observed not only as a function of tropic stature for fish in the reach impacted by SBC, but also for macroinvertebrates with predator species having higher concentrations than collectors and omnivorous.

  19. Diffusive release of uranium from contaminated sediments into capillary fringe pore water

    SciTech Connect

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

    2012-01-01

    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.

  20. Microbial diversity in shallow-water hydrothermal sediments of Kueishan Island, Taiwan as revealed by pyrosequencing.

    PubMed

    Wang, Li; Cheung, Man Kit; Kwan, Hoi Shan; Hwang, Jiang-Shiou; Wong, Chong Kim

    2015-11-01

    Kueishan Island is a young volcanic island in the southernmost edge of the Okinawa Trough in the northeastern part of Taiwan. A cluster of hydrothermal vents is located off the southeastern tip of the Island at water depths between 10 and 80 m. This paper presents the results of the first study on the microbial communities in bottom sediments collected from the shallow-water hydrothermal vents of Kueishan Island. Small-subunit ribosomal RNA gene-based high-throughput 454 pyrosequencing was used to characterize the assemblages of bacteria, archaea, and small eukaryotes in sediment samples collected at various distances from the hydrothermal vents. Sediment from the vent area contained the highest diversity of archaea and the lowest diversity of bacteria and small eukaryotes. Epsilonproteobacteria were the most abundant group in the vent sediment, but their abundance decreased with increasing distance from the vent area. Most Epsilonproteobacteria belonged to the mesophilic chemolithoautotrophic genera Sulfurovum and Sulfurimonas. Recent reports on these two genera have come from deep-sea hydrothermal vents. Conversely, the relative contribution of Gammaproteobacteria to the bacterial community increased with increasing distance from the vent area. Our study revealed the contrasting effects of venting on the benthic bacterial and archaeal communities, and showed that the sediments of the shallow-waters hydrothermal vents were dominated by chemoautotrophic bacteria. The present work broadens our knowledge on microbial diversity in shallow-water hydrothermal vent habitats. PMID:26132902

  1. Analysis of heavy metals concentration in water and sediment in the Hara biosphere reserve, southern Iran.

    PubMed

    Nowrouzi, Mohsen; Mansouri, Borhan; Nabizadeh, Sahar; Pourkhabbaz, Alireza

    2014-02-01

    This study determined the concentration of heavy metals (Al, Cr, Cu, and Zn) in water and sediments at nine sites in the Hara biosphere reserve of southern Iran during the summer and winter 2010. Determination of Al, Cr, Cu, and Zn in water was carried out by graphite furnace atomic absorption spectrometer (Shimadzu, AA 610s) and in sediment by flame atomic absorption spectrometer (Perkin Elmer, AA3030). Results showed that the heavy metal concentrations in the water samples decreased in the sequence of Zn>Al>Cu>Cr, while in sediment samples were Cr>Zn>Cu>Al. Data analysis indicated that with the exception of Al, there was a Pearson's correlation coefficient between pH and Cu, Zn, and Cr at ?=0.01, 0.05, and 0.001 in sediment (in winter), respectively. There were also significant differences between heavy metals of Cr, Cu, and Zn during the two seasons (p<0.001) in the water and sediment. PMID:22740619

  2. Identification of Water-Quality Trends Using Sediment Cores from Dillon Reservoir, Summit County, Colorado

    USGS Publications Warehouse

    Greve, Adrienne I.; Spahr, Norman E.; Van Metre, Peter C.; Wilson, Jennifer T.

    2001-01-01

    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.

  3. Total and Methyl Mercury Distribution in Water, Sediment, and Fish tissue in New England Streams

    NASA Astrophysics Data System (ADS)

    Chalmers, A. T.; Krabbenhoft, D. P.

    2001-05-01

    Conditions that are conducive to the methylation of mercury are of particular concern because methyl mercury (MeHg) is the most toxic mercury species and is rapidly bioaccumulated and biomagnified in wildlife and man. The New England Coastal Basins study unit, as part of the U.S. Geological Survey's National Water Quality Assessment program, has evaluated relations between concentrations of total mercury (HgT) and MeHg in stream water and bed sediment, and HgT in fish tissue at sites with a variety of watershed characteristics. Fifty-five stream sites from Rhode Island to Maine were sampled for water and bed sediment during 1998 - 2000. A subset of 27 sites was sampled for fish tissue. Sediment, water, and fish tissue samples were collected during summer low flow conditions within a week of each other to show patterns of MeHg accumulation and partitioning relative to site and watershed conditions. Concentrations of HgT in water and bed sediment ranged from 1 to 13 nanograms per liter (ng/L) and from 7 to 3,100 nanograms per gram (ng/g) dry weight, respectively. Concentrations of MeHg in water and sediment ranged from 0.04 to 1.8 ng/L and from 1 to 38 ng/g dry weight, respectively, and were positively correlated with concentrations of organic carbon. Methylation efficiency, as estimated by MeHg/HgT, ranged from 0.003 to 0.282 for sediment and water samples, with a median value of 0.071. Methylation efficiency was highest at sampling sites with low urbanization and high organic carbon concentrations. HgT concentrations in fish tissue (mixed sunfish species) ranged from 42 to 349 ng/g wet weight and were positively correlated with concentrations of MeHg in water and bed sediment. A positive relation was not observed between HgT concentrations in fish tissue and HgT concentrations in water and bed sediment. These preliminary results indicate a high potential for mercury bioaccumulation in aquatic organisms in New England streams.

  4. [Influence of combined ecological floating bed on nitrogen and phosphorus between overlying water and sediment].

    PubMed

    Zheng, Li-Guo; Yang, Ren-Bin; Wang, Hai-Ping; Song, Jian-Jun

    2013-08-01

    A new type of combined ecological floating bed was developed on Swan Lake. It was combined with aquatic and hydrophilous plants and ancillary equipments that included floating controllers, water-cycling aerator systems and wave-making systems. Combined ecological floating bed changed the physical and chemical environment of Swan Lake and had an effect on the transportation and transformation of TN, NH4(+) -N and TP between overlying water and sediment during the experiment. The concentration change of TN, NH4(+) -N and TP and the effect of DO, Eh and pH on the nutrient in the overlying water and sediment were investigated. The results indicated that: in overlying water, the removal efficiencies of TN, NH4(+) -N and TP were 61.92%, 63.09% and 80.0%, respectively; the removal efficiencies of TN and NH4(+) -N were 23.79% and 37.04%, respectively; the concentration of TP increased by 43.71% in sediment during the experiment. The combined ecological floating bed influenced environmental factors such as DO, Eh and pH in overlying water in some degree. DO concentration rose from 8.7-8.9 mg x L(-1) to 9.3-10.4 mg x L(-1), and Eh concentration was from 163-178 mV to 191-198 mV. Both of them were higher than those in the contrast area. Phosphorus release was inhibited, and phosphorus adsorption was promoted through improving DO and Eh of the overlying water. The pH volatility was less and maintained between 7.51 and 8.32, and did not promote phosphorus release in sediment. TN, TP and NH4(+) -N in overlying water and TN and NH4(+) -N in sediment were significantly positively correlated with each other and with TP in sediment. The pH had no significant correlation with TN, TP and NH4(+) -N in overlying water and sediment. DO was significantly positively corrected with Eh in overlying water and was significantly negatively corrected with TP in sediment. PMID:24191549

  5. Sediment transport and evaluation of sediment surrogate ratings in the Kootenai River near Bonners Ferry, Idaho, Water Years 2011–14

    USGS Publications Warehouse

    Wood, Molly S.; Fosness, Ryan L.; Etheridge, Alexandra B.

    2015-01-01

    Acoustic surrogate ratings were developed between backscatter data collected using acoustic Doppler velocity meters (ADVMs) and results of suspended-sediment samples. Ratings were successfully fit to various sediment size classes (total, fines, and sands) using ADVMs of different frequencies (1.5 and 3 megahertz). Surrogate ratings also were developed using variations of streamflow and seasonal explanatory variables. The streamflow surrogate ratings produced average annual sediment load estimates that were 8–32 percent higher, depending on site and sediment type, than estimates produced using the acoustic surrogate ratings. The streamflow surrogate ratings tended to overestimate suspended-sediment concentrations and loads during periods of elevated releases from Libby Dam as well as on the falling limb of the streamflow hydrograph. Estimates from the acoustic surrogate ratings more closely matched suspended-sediment sample results than did estimates from the streamflow surrogate ratings during these periods as well as for rating validation samples collected in water year 2014. Acoustic surrogate technologies are an effective means to obtain continuous, accurate estimates of suspended-sediment concentrations and loads for general monitoring and sediment-transport modeling. In the Kootenai River, continued operation of the acoustic surrogate sites and use of the acoustic surrogate ratings to calculate continuous suspended-sediment concentrations and loads will allow for tracking changes in sediment transport over time.

  6. Phthalate esters in water and sediments of the Kaveri River, India: environmental levels and ecotoxicological evaluations.

    PubMed

    Selvaraj, Krishna Kumar; Sundaramoorthy, Gomathy; Ravichandran, Praveen Kumar; Girijan, Girish Kumar; Sampath, Srimurali; Ramaswamy, Babu Rajendran

    2015-02-01

    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

  7. Independent component analysis of local-scale temporal variability in sediment-water interface temperature

    NASA Astrophysics Data System (ADS)

    Middleton, M. A.; Whitfield, P. H.; Allen, D. M.

    2015-12-01

    Temperature recorded at the sediment-water interface has been identified as a valuable tracer for understanding groundwater-surface water interactions. However, factors contributing to the variability in temperatures can be difficult to distinguish. In this study, the temporal variability in daily temperatures at the sediment-water interface is evaluated for a 40 m reach of a coastal stream using Independent Component Analysis (ICA). ICA separation is used to identify three independent temperature components within the reach for each of four summer periods (2008-2011). Extracted temperature signals correlate with stream discharge, estimated streambed temperature, and groundwater level, but the strength of the correlations varies from summer to summer. Overall, variations in the temperature signals have clearer separation in summers with lower stream discharge and greater stream temperature ranges. Surface heating from solar radiation is the dominant factor influencing the sediment-water interface temperature in most years, but there is evidence that thermal exchanges are taking place other than at the air-water interface. These exchanges take place at the sediment-water interface, and the correlation with groundwater levels indicates that these heat exchanges are associated with groundwater inflow. This study demonstrates that ICA can be used effectively to aid in identifying component signals in environmental applications of small spatial scale.

  8. Particle Size Distribution in the Yellow River Plume before and during Water and Sediment Diversion

    NASA Astrophysics Data System (ADS)

    Zou, T.; Zhang, H.

    2014-12-01

    Particle size distribution (PSD) is a critical measurement of the sediment fluxes and deposition that has not been adequately studied. Knowledge of the spatial and temporal variation of PSD can be used to evaluate the interaction between suspended sediment and biological and chemical components in coastal ocean. In this study the PSD were measured at more than 100 sites in the Yellow River Plume (YRP) before and after water and sediment diversion using a laser diffractometer (LISST-100X Type-B) in concert with multiple biogeochemical parameters collected during summer 2014. The measured PSD is fitted with Junge distribution to obtain the power-law slope and the differential number concentration for reference diameter. Results show that the total suspended particles ranged between 10 and 654 ?L L-1, median particle diameter (d0.5) ranged between 21 and 281?m, power-law fitted PSD slopes ranged from 3.2 to 4.4, reflecting the dominance of inorganic particles associated with the sediment discharged from the Yellow River. The spatial distribution of PSD also clearly displayed a dominant effect of riverine inputs. The depth-distribution of PSD slopes indicated that the deposition-resuspension process might be an important factor of the sediment dynamics. Our study provides valuable information on the distribution and transport of sediment discharged from the Yellow River in surrounding coastal water.

  9. A Coupled Biogeochemical Reactive Transport Model in Bed Sediments and Water Column of Riverine Systems

    NASA Astrophysics Data System (ADS)

    Massoudieh, A.; Bombardelli, F. A.; Sengor, S. S.; Ginn, T. R.

    2007-12-01

    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.

  10. Development of a gas backup heater for solar domestic hot-water systems. Final report, April 1978-April 1980

    SciTech Connect

    Morrison, D.J.; Grunes, H.E.; de Winter, F.; Armstrong, P.R.

    1980-06-01

    A comprehensive program was undertaken to develop a unique gas fired backup for solar domestic hot water systems. Detailed computer design tools were written. A series of heat transfer experiments were performed to characterize the performance of individual components. A full scale engineering prototype, including the solar preheat tank and solar heat exchanger, was designed, fabricated and subjected to limited testing. Firing efficiency for the backup system was found to be 81.4% at a firing rate of 50,000 Btu/h. Long term standby losses should be negligible.

  11. Characterization of domestic gray water from point source to determine the potential for urban residential reuse: a short review

    NASA Astrophysics Data System (ADS)

    Edwin, Golda A.; Gopalsamy, Poyyamoli; Muthu, Nandhivarman

    2014-03-01

    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.

  12. Solar heating and domestic hot water system installed at Kansas City, Fire Station, Kansas City, Missouri. Final report

    SciTech Connect

    1980-07-01

    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.

  13. Impact of Water Column Acidification on Protozoan Bacterivory at the Lake Sediment-Water Interface

    PubMed Central

    Tremaine, Sarah C.; Mills, Aaron L.

    1991-01-01

    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. Protozoon-bacterium interactions were investigated in a chronically acidified (acid mine drainage) portion of a lake in Virginia. We 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-1, values similar to those in unacidified systems. The protozoan community from an acidified station was not better adapted (P = 0.95) 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 (P < 0.05) 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-protozoon link of the sediment microbial food web. PMID:16348443

  14. Impact of water column acidification on protozoan bacterivory at the lake sediment-water interface

    SciTech Connect

    Tremaine, S.C.; Mills, A.L. )

    1991-03-01

    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.

  15. Geochemical cycling and speciation of copper in waters and sediments of Macquarie Harbour, Western Tasmania

    NASA Astrophysics Data System (ADS)

    Teasdale, P. R.; Apte, S. C.; Ford, P. W.; Batley, G. E.; Koehnken, L.

    2003-06-01

    The factors determining the concentration and speciation of copper in the waters and sediments of Macquarie Harbour, Tasmania were investigated. This harbour is the most extensively copper-contaminated estuarine water body in Australia owing to current and historical inputs of metal-rich waters and sediments from the nearby Mount Lyell copper mine. The dissolved copper concentrations in the harbour water column were highly variable (4-560 μg l -1) and displayed a north to south gradient, decreasing with distance from the King River, which carries the inputs from the mine. The most significant process affecting dissolved copper concentrations was the neutralisation of acidic river waters with seawater and the resulting coprecipitation with iron oxyhydroxide flocs. Approximately 60% of the riverine dissolved copper input was removed from solution by this process. Particulate copper concentrations in surficial benthic sediments were high in most regions of the harbour (typically 0.5-1 mg g -1). In the north, sediments were dominated by fine, mine-derived material and showed uniform particulate copper concentrations with depth. Sediment acid-volatile sulphide concentrations were highest (11-142 μmol g -1) in the southern harbour and were barely detectable in the northern harbour region (<0.46 μmol g -1). A similar north-south gradient of sediment organic carbon concentrations was observed. Very high porewater concentrations of copper (up to 520 μg l -1) and iron (200 mg l -1) were found at sites in the northern harbour. The high porewater copper concentrations are believed to result from the oxidation of porewater Fe(II), formation of amorphous iron oxyhydroxide and the associated pH-related dissolution of particulate copper. Calculations indicated a positive flux of dissolved copper from the sediments at sites in the northern harbour. However, in the southern harbour, the high acid volatile sulphide concentrations of the sediments meant that they acted as a sink for dissolved copper, resulting in low porewater copper concentrations (<1-10 μg l -1) and a significant copper flux from the overlying water to the sediment. The study illustrates the roles of iron redox chemistry, associated pH gradients, and acid volatile sulphide in controlling copper mobility in contaminated estuarine environments.

  16. Sediment Mobilization From Reservoirs Can Cause Short Term Oxygen Depletion In Downstream Receiving Waters

    NASA Astrophysics Data System (ADS)

    Anderson, C.; Schenk, L.; Bragg, H.; Singer, M.; Hume, N.

    2013-12-01

    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.

  17. Distribution of silicones in water, sediment and fish in Japanese rivers.

    PubMed

    Watanabe, N; Nagase, H; Ose, Y

    1988-07-01

    A new analytical method for assaying polyorganosiloxanes (silicones) in environmental samples is presented. The method utilizes petroleum for solvent extraction of the sample (water, sediment, biological tissue) together with inductively coupled plasma detection of the extracted organic silicones. The detection limit for silicones in the final methyl isobutyl ketone sample/extract is approximately 0.01 ppm, and the method is applied to samples from various Japanese rivers to quantify silicones in several environmental materials. Silicones are reported from river waters (up to approximately 50 ppb), riverine sediments (up to 6 ppm), and as an extractable component of fish tissue (up to approximately 0.9 ppm). PMID:3212447

  18. Water and sediment transport modeling of a large temporary river basin in Greece.

    PubMed

    Gamvroudis, C; Nikolaidis, N P; Tzoraki, O; Papadoulakis, V; Karalemas, N

    2015-03-01

    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

  19. HPLC-PFD determination of priority pollutant PAHs in water, sediment, and semipermeable membrane devices

    USGS Publications Warehouse

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

    2002-01-01

    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.

  20. Aquatic Sediments.

    ERIC Educational Resources Information Center

    Sanville, W. D.; And Others

    1978-01-01

    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)

  1. Sediment and water discharge rates of Turkish Black Sea rivers before and after hydropower dam construction

    SciTech Connect

    Hay, B.J. )

    1994-06-01

    Presently, the water discharge rate to the Black Sea by Turkish rivers is approximately 41 km[sup 3]/yr. The sediment discharge rate of Turkish rivers to the Black Sea is 28 x 10[sup 6] t/yr. Before construction of the hydroelectric dams, the sediment discharge rate was approximately 70 x 10[sup 6] t/yr. The sharp reduction in sediment load is largely a result of the dams near the mouths of the Yesil Irmak and Kizil Irmak rivers. Before the construction of dams, Turkish rivers contributed approximately one third of the total amount of sediment received by the Black Sea from all surrounding rivers. The life-span of the major reservoirs varies from approximately only one century (Yesil Irmak river reservoirs) to several thousand years (Sakarya river reservoirs). Life-span for the large Altinkaya Dam reservoir is estimated with approximately 500 yr.

  2. Modeling water and sediment contamination of Lake Pontchartrain following pump-out of Hurricane Katrina floodwater.

    PubMed

    Dortch, Mark S; Zakikhani, Mansour; Kim, Sung-Chan; Steevens, Jeffery A

    2008-05-01

    Levee failure and overtopping as a result of Hurricane Katrina caused major flooding of New Orleans, Louisiana. Floodwaters, which were contaminated with heavy metals, organic chemicals, and fecal coliform bacteria (FCB), were pumped into neighboring Lake Pontchartrain during dewatering. The impact of levee failure on water and benthic sediment concentrations in the lake was investigated by applying a numerical water quality model coupled to a three-dimensional, numerical hydrodynamic model. The model was used to compute water and benthic sediment concentrations throughout the lake for lead, arsenic, benzo(a)pyrene (BaP), and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE), and water concentrations for FCB. Computed concentrations resulting from actual pumped discharges with levee failure and overtopping were compared to computed concentrations resulting from pumped discharges without levee failure or overtopping, and concentrations from both sets of conditions were compared to ecological water and sediment quality screening guideline values. The model indicated that incremental increases above pre-Katrina benthic sediment concentrations are about a factor of 10 greater with dewatering of the floodwaters than with dewatering of storm water without flooding. However, these increases for the metals are small relative to pre-Katrina concentrations. The results showed that the ecological screening-level sediment quality guideline values were exceeded for BaP and DDE in areas near the south shoreline of the lake as a result of floodwater pump-out, whereas, this was not the case for storm water removal without flooding. The model showed that lake water column concentrations should be about the same during both dewatering conditions regardless of whether there is flooding or not. PMID:17399885

  3. Potential of solar domestic hot water systems in rural areas for greenhouse gas emission reduction in Poland

    SciTech Connect

    Skowronski, P.; Wisniewski, G.

    1996-09-01

    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 CO{sub 2} and NOx will increase. The emission of CO and CH{sub 4} 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 CO{sub 2} emission reduction. The rate of realization of the economic potential of solar water heaters depends on subsidies for the installation of equipment. 13 refs., 9 tabs.

  4. Post-irrigation impact of domestic sewage effluent on composition of soils, crops and ground water--a case study.

    PubMed

    Yadav, R K; Goyal, B; Sharma, R K; Dubey, S K; Minhas, P S

    2002-12-01

    Long-term irrigation with sewage water adds large amounts of carbon, major and micro- nutrients to the soil. We compared the spatial distribution of N, P, K and other micronutrients and toxic elements in the top 0.6 m of an alluvial soil along with their associated effects on the composition of crops and ground waters after about three decades of irrigation with domestic sewage effluent as a function of distance from the disposal point. Use of sewage for irrigation in various proportions improved the organic matter to 1.24-1.78% and fertility status of soils especially down to a distance of 1 km along the disposal channel. Build up in total N was up to 2908 kg ha(-1), available P (58 kg ha(-1)), total P (2115 kg ha(-1)), available K (305 kg ha(-1)) and total K (4712 kg ha(-1)) in surface 0.15 m soil. Vertical distribution of these parameters also varied, with most accumulations occurring in surface 0.3 m. Traces of NO3-N (up to 2.8 mg l(-1)), Pb (up to 0.35 mg l(-1)) and Mn (up to 0.23 mg l(-1)) could also be observed in well waters near the disposal point thus indicating initiation of ground water contamination. However, the contents of heavy metals in crops sampled from the area were below the permissible critical levels. Though the study confirms that the domestic sewage can effectively increase water resource for irrigation but there is a need for continuous monitoring of the concentrations of potentially toxic elements in soil, plants and ground water. PMID:12503913

  5. Nutrient exchange across the sediment-water interface in the Potomac River estuary

    USGS Publications Warehouse

    Callender, E.; Hammond, Douglas E.

    1982-01-01

    The flux of ammonia, phosphate, silica and radon-222 from Potomac tidal river and estuary sediments is controlled by processes occurring at the sediment-water interface and within surficial sediment. Calculated diffusive fluxes range between 0??6 and 6??5 mmol m-2 day-1 for ammonia, 0??020 and 0??30 mmol m-2 day-1 for phosphate, and 1??3 and 3??8 mmol m-2 day-1 for silica. Measured in situ fluxes range between 1 and 21 mmol m-2 day-1 for ammonia, 0??1 and 2??0 mmol m-2 day-1 for phosphate, and 2 and 19 mmol m-2 day-1 for silica. The ratio of in situ fluxes to diffusive fluxes (flux enhancement) varied between 1??6 and 5??2 in the tidal river, between 2??0 and 20 in the transition zone, and from 1??3 to 5??1 in the lower estuary. The large flux enhancements from transition zone sediments are attributed to macrofaunal irrigation. Nutrient flux enhancements are correlated with radon flux enhancements, suggesting that fluxes may originate from a common region and that nutrients are regenerated within the upper 10-20 cm of the sediment column. The low fluxes of phosphate from tidal viver sediments reflect the control benthic sediment exerts on phosphorus through sorption by sedimentary iron oxyhydroxides. In the tidal river, benthic fluxes of ammonia and phosphate equal one-half and one-third of the nutrient input of the Blue Plains sewage treatment plant. In the tidal Potomac River, benthic sediment regeneration supplies a significant fraction of the nutrients utilized by primary producers in the water column during the summer months. ?? 1982.

  6. Provision of safe domestic water for the promotion and protection of public health: a case study of the city of Beirut, Lebanon.

    PubMed

    Korfali, Samira Ibrahim; Jurdi, Mey

    2009-04-01

    Securing adequate safe drinking water and proper sanitation is a major challenge facing the developing world. The "Water for Life Decade" emphasizes the importance of upgrading national water quality and sanitation services. This study assessed the domestic water profile in the city of Beirut. Samples were collected from three types of household water sources (municipality, private wells, and vended water bottles) and assessed for their physiochemical and microbiological profile. At the same time, a cross-sectional survey assessing water consumption patterns and the prevalence of water-borne diseases was conducted. The results showed a deficient water quality profile in all three water sources. The measured physiochemical and bacteriological parameters reflected the high frequency of water-borne diseases. Action to secure a safe domestic water supply is essential. The plan should guarantee the protection of water sources, ensure sufficient treatment of domestic water and upgrade the national program for potable water quality control. Periodic quality monitoring and legislating the chaotic water-vending sector are indispensable. Additionally, the deterioration of private well sources by sea and wastewater infiltration necessitates the enforcement of legislation associated with the use and management of private wells. Consumer awareness and active contributions to promote and protect public health are important. PMID:18958397

  7. Impacts of sewage of a pulp and paper industry on the sediments of Vigozero water basin

    NASA Astrophysics Data System (ADS)

    Natalia, Belkina

    2010-05-01

    The studies of sediments of Vigozero reservoir with 1969 for 2009 are presented. Vigozero water basin belongs to pool of the White Sea. It's watershed area is 16 800 km2, water surface area is 1140 km2, volume of lake - 6,46 km3, average depth - 6,2 m, the maximum depth - 23 m, the water residence time -1,14 years. Northern part of Vigozero reservoir tests influence of sewage of Segeja pulp and paper mill, operating since 1938. Zones of pollution of a bottom are allocated: 1- solid waste; 2 - active silt, lignin, cellulose; 3 - transformed suspended solids. Distribution and stratification of deposits, their physical and chemical parameters is investigated. It is shown, that change of a chemical compound of sediments is connected with volume and qualitative of sewage. The tendency to the extension of polluted zones and to spreading of organic pollution all the bottom is considered. Maximum settling velocity was fixed in 1980 -1985. Accumulation of the organic compounds in sediments at that time resulted in the development of high internal loading. Change of an ecological situation in Vigozero water basin, connected with falling volumes of manufacture last 20 years, has affected sediment genesis processes, therefore the concentrations of organic substances and biogenic elements have decreased in a superficial layer of sediments, concentration of iron has increased. Now, transformation of the organic substances, which have been saved up earlier, demands significant amounts of oxygen. Variability of pH and Eh of sediments indicates unstable oxidation-reduction conditions. Ore formations on a redox-barrier interfere with transport of substances from deposits in water. The work was supported in part by Russian Foundation for Basic Research (grant № 08-05-98811).

  8. Local scale marine modelling of Fukushima releases. Assessment of water and sediment contamination and sensitivity to water circulation description.

    PubMed

    Periez, R; Suh, Kyung-Suk; Min, Byung-Il

    2012-11-01

    The dispersion of (137)Cs released from Fukushima nuclear power plant to the sea after the March 11th 2011 tsunami has been studied using numerical models. The 3D dispersion model consists of an advection/diffusion equation with terms describing uptake/release reactions between water and seabed sediments. The dispersion model has been fed with daily currents provided by HYCOM and JCOPE2 ocean models. Seabed sediment (137)Cs patterns obtained using both current data set have been compared. The impact of tides and of atmospheric deposition has been evaluated as well. It has been also found that a 2-step kinetic model (two consecutive reversible reactions) for describing water/sediment interactions produces better results than a 1-step model (one single reversible reaction). PMID:23021937

  9. Zinc, copper, cadmium, and lead concentrations in water, sediment, and Anadara senilis in a tropical estuary.

    PubMed

    Bakary, Inza; Yao, Koffi Marcellin; Etchian, Olivier Assoi; Soro, Metongo Bernard; Trokourey, Albert; Bokra, Yobou

    2015-12-01

    Spatial and seasonal contaminations of zinc, copper, cadmium, and lead were assessed simultaneously in water, sediment, and in the bivalve Arca senilis from the Milliardaires Bay (Cote d'Ivoire) between February and October 2008. The metal load in sediments doubled from the dry season to the rainy season. On the contrary, metal concentrations in waters decreased significantly from the dry season to the rainy season. Zn and Pb concentrations in A. senilis showed similar seasonal variation with sediments. On the other hand, A. senilis regulated Cu concentrations by eliminating about twelve times the concentration accumulated during the dry season. Apparent Zn, Cu, Cd, and Pb concentration gradients were observed, but no significant differences between stations for sediment, water, and A. senilis. Concentrations in sediment increased from stations close to Abidjan Harbor towards farther stations, while concentrations in A. senilis showed a reverse gradient. The distribution gradient of A. senilis indicates pollution from local sources, but a transplant experiment is needed to better understand the observed spatial trend. Zn and Cu concentrations may pose little risk to human health and the environment, but they are the highest on the regional scale. On the contrary, Cd and Pb concentrations in A. senilis exceeded the maximum allowable limits set by the European Commission. Complementary studies including chemical speciation should be considered to provide a more accurate assessment of the risk of heavy metals to the environment. PMID:26581608

  10. Widespread potential for microbial MTBE degradation in surface-water sediments

    USGS Publications Warehouse

    Bradley, P.M.; Landmeyer, J.E.; Chapelle, F.H.

    2001-01-01

    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.

  11. Occurrence of arsenic in sediment pore waters in the central Kanto Plain, Japan

    NASA Astrophysics Data System (ADS)

    Hachinohe, Shoichi; Hamamoto, Hideki; Ishiyama, Takashi; Hossain, Sushmita; Oguchi, Chiaki T.

    2014-05-01

    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.

  12. Partitioning of Total Dissolved Salts, Boron and Selenium in Pariette Wetland Water, Sediments and Benthic Organisms

    NASA Astrophysics Data System (ADS)

    Jacobson, A. R.; Jones, C. P.; Vasudeva, P.; Powelson, D.; Grossl, P.

    2014-12-01

    The Pariette Wetlands located in the Uinta Basin, UT, were developed by the BLM in part to mitigate salinity associated with irrigation drainage and runoff from flowing to the Green River, a tributary of the Colorado River. The wetlands are fed by runoff from upstream agricultural irrigation, and natural subsurface and overland flow through the Uintah formation, which is seleniferous, and saline. Concentrations of Total Dissolved Salts (TDS), boron (B) and selenium (Se) in the wetlands exceed the total maximum daily loads developed to meet the US EPA's water quality planning and management regulations (40CFR 130). This is of concern because the wetlands are home to populations of migratory birds, waterfowl, raptors, and numerous small mammals. A mass balance of the Se concentrations of water flowing into and out of the wetlands indicates that 80% of the Se is stored or lost within the system. Additional data suggest that the majority of the Se is associated with the sediments. Little information is available regarding the TDS and B. Therefore we will determine the whether B and other salts are accumulating in the wetland systems, and if so where. We sampled water, sediment, benthic organisms, and wetland plants, in 4 of the 23 ponds from the flood control inlet to water flowing out to the Green River. Sediments were collected at 3 depths (0-2 cm, 2-7 cm, and 7+ cm) at 3-4 locations within each pond including the inlet, outlet and at least one site near a major wetland plant community. Benthic organisms were sampled from the 0-2 cm and 2-7 cm sediment layers. Sediment and organism samples were digested with HNO3 and HClO4 prior to analysis of total Se by HGAAS. Hot water extractable B and DPTA extractable B were analyzed by ICP-AES. TDS was estimated from EC in the sediment and organisms extracts and direct analysis in the water. Preliminary results found that Se in the sediments decreases with depth. Se concentrations in the benthic organisms is approximately 4 times higher than in the associated sediments. Data from this study will contribute to a water quality risk assessment to the wetland fish and birds.

  13. Degradation of metolachlor in bare and vegetated soils and in simulated water-sediment systems.

    PubMed

    Mersie, Wondi; McNamee, Clyde; Seybold, Cathy; Wu, Jigang; Tierney, Dennis

    2004-11-01

    A study was conducted to determine the half-life (t1/2), degradation rate, and metabolites of metolachlor in a water-sediment system and in soil with and without switchgrass. Metolachlor degradation in a laboratory was determined in sediment from Bojac sandy loam soil incubated at 24 degrees C. The study also was conducted in a greenhouse on tilted beds filled with Bojac soil and planted with switchgrass. In both experiments, samples were collected at days 0, 7, 14, 28, 42, 56, and 112 and analyzed for metolachlor and its major metabolites. The water-sediment oxidation-reduction potential took 28 d to reach -371 mV and the pH increased from 5.6 to 6.5 by the last sampling day (day 112). The average soil temperature of the tilted beds with or without switchgrass during the study was 21degrees C and the soil moisture content was 23% by volume. The t1/2 of metolachlor was 34 d in sediment and 8 d in the water phase. The t1/2 of metolachlor in soil from the switchgrass filter strip (6 d) was not different from that in soil without grass (9.6 d). The metolachlor metabolites ethanesulfonic acid (ESA) and oxanilic acid (OA) were detected in the water-sediment system and in soil from tilted beds. In both sediment and soil from tilted beds, the two metabolites peaked by day 56 of incubation and declined after that, indicating transformation to other products. In the water-sediment system, greater quantities of OA and ESA were detected in sediment than in the aqueous phase. The production of OA and ESA in the watersediment system occurred in the first 28 d, when the system was at an aerobic redox state. Metolachlor can degrade in sediment and the relatively high soil temperature and moisture level accelerated its breakdown in beds with and without switchgrass. Under warm and moist soil conditions, the presence of switchgrass has no effect on the degradation of metolachlor. PMID:15559277

  14. Pharmaceutical residues in water and sediment of Msunduzi River, KwaZulu-Natal, South Africa.

    PubMed

    Matongo, Solomon; Birungi, Grace; Moodley, Brenda; Ndungu, Patrick

    2015-09-01

    The little data about pharmaceutical residue contamination in African water bodies motivated our study on the occurrence of pharmaceutical residues in the water and sediment of Msunduzi River in the KwaZulu-Natal province of South Africa; and in the Darvill wastewater treatment plant found in Msunduzi catchment. Samples collected along the River and wastewater treatment plant were extracted and analysed for pharmaceutical residues selected based on statistics of drug usage in South Africa i.e. antipyretics, antibiotics, caffeine, an antiepileptic and an antipsychotic drug were determined using HPLC-MS/MS. In all the matrices investigated, the antipyretic ibuprofen had the highest concentration of up to 117 ?g L(-1), 84.60 ?g L(-1) and 659 ng g(-1) in wastewater, surface water and sediment respectively. Antibiotics were detected in generally low concentrations of<10 ?g L(-1) in surface water samples and up to 34.50 ?g L(-1) in wastewater; moreover they were not completely removed during wastewater treatment. The percentage removal efficiency of the studied group was 6.55-98.00% for antipyretics, 73.33-98.90% for antibiotics, 48.80% for the anti-epileptic drug and 86.40% for Caffeine. Clozapine exhibited a negative removal. In surface water, Henley dam exhibited a high concentration of the pharmaceutical residues and the highest concentration of metronidazole in sediment (up to 1253.50 ng g(-1)) detected. Metronidazole was only detected in sediment and bio-solids. PMID:25935602

  15. Physicochemical and Analytical Data for Tributary Water, Lake Water, and Lake Sediment, Lake Arrowhead, Clay and Archer Counties, Texas, 2006

    USGS Publications Warehouse

    Wilson, Jennifer T.; Musgrove, MaryLynn; Haynie, Monti M.; Van Metre, Peter C.

    2008-01-01

    Lake Arrowhead is a reservoir about 24 kilometers southeast of Wichita Falls, Texas, that provides drinking water for the city of Wichita Falls and surrounding areas. The U.S. Geological Survey, in cooperation with the City of Wichita Falls, did a study in 2006 to assess conditions contributing to elevated arsenic concentrations in Lake Arrowhead. This report describes the sampling and analytical methods, quality assurance, and physicochemical and analytical data. Physiochemical properties were measured in and water samples were collected from five tributaries to Lake Arrowhead (Little Wichita River, West Little Post Oak Creek, East Little Post Oak Creek, Deer Creek, and an unnamed tributary) immediately after storms. Lake water measuring and sampling were done approximately monthly from January through September 2006 at three deep-water sites and seasonally, in January and August 2006, at three shallow-water sites. Cores of lake bottom sediment were collected from five sites on August 30, 2006. Arsenic concentrations in tributary water samples ranged from 1.5 to 6.3 and 0.5 to 4.8 micrograms per liter for unfiltered and filtered samples, respectively. The highest arsenic concentrations were in samples collected from the West Little Post Oak Creek sampling site. Physicochemical properties in lake water varied with depth and season. Dissolved arsenite plus arsenate concentrations in lake water samples generally were between 3 and 5 micrograms per liter. Arsenite concentrations typically were below the laboratory reporting level of 0.6 microgram per liter. There were no detections of monomethylarsonate or dimethylarsinate. The concentration of arsenic in lake sediment samples ranged from 4.4 to 11.2 milligrams per kilogram, with a median of 6.4 milligrams per kilogram. The median arsenic concentration of the five top-interval sediment samples was 8.8 milligrams per kilogram, which generally is higher than the concentrations estimated to be on suspended sediment in the tributaries. Sediment concentrations of seven trace elements were compared to two consensus-based sediment quality guidelines for each: the threshold effect concentration and the probable effect concentration. Arsenic concentration exceeded the threshold effect concentration in one top-interval sediment sample.

  16. Contribution of 222Rn in domestic water supplies to 222Rn in indoor air in Colorado homes

    USGS Publications Warehouse

    Lawrence, E.P.; Wanty, R.B.; Nyberg, P.

    1992-01-01

    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.

  17. Comparison of whole-sediment, elutriate and pore-water exposures for use in assessing sediment-associated organic contaminants in bioassays

    SciTech Connect

    Harkey, G.A. Clemson Univ., Pendleton, SC ); Landrum, P.F. ); Klaine, S.J. )

    1994-08-01

    Bioassays have frequently been used as tools to simulate exposure of benthos to sediment-associated contaminants in hazard assessments. Due to the problems involved with estimating bioavailability in whole-sediment bioassays, aqueous fractions such as elutriates and pore water have been substituted for whole-sediment exposures. The objective of this research was to compare and evaluate the bioavailability of representative neutral hydrophobic contaminants in whole sediments and in aqueous extracts of whole sediment in simultaneous bioassays, using three representative indicator species, Diporeia spp., Chironomus riparius larvae, and Lumbriculus variegatus. Aqueous extracts of whole sediment did not accurately represent the exposure observed in whole sediment. Generally, the aqueous extracts underexposed organisms compared to whole sediment, even after adjusting accumulation to the fraction of organic carbon in the test media. Accumulation comparisons among whole-sediment, elutriate, and pore-water exposures depended on sampling time. At some sampling times for some contaminants, differences in accumulation between a particular aqueous extract and whole sediment were not significant; however, these similarities were not observed for all species at the particular sampling time. Bioaccumulation and contaminant clearance data suggest that a number of factors such as the indicator species, exposure media, and chemical/physical properties of individual contaminants are responsible for the accumulation differences observed among the tested media. Normalizing bioaccumulation to the amount of organic carbon in a source compartment adjusted for bioavailability differences of only some contaminants. The authors suggest that the bioavailability of contaminants such as those tested cannot be accurately predicted in bioassays that expose organisms to aqueous representations of whole sediment.

  18. Critical velocity in phosphorus exchange processes across the sediment-water interface.

    PubMed

    Wan, Jun; Wang, Ze; Li, Zhijie; Duan, Huiling; Hezhong, Yuan

    2013-10-01

    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

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

    NASA Astrophysics Data System (ADS)

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

    2014-09-01

    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 μm) 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.

  20. A possible case of caprine-associated malignant catarrhal fever in a domestic water buffalo (Bubalus bubalis) in Switzerland

    PubMed Central

    2011-01-01

    Background Malignant catarrhal fever (MCF) is a fatal herpesvirus infection, affecting various wild and domestic ruminants all over the world. Water buffaloes were reported to be particularly susceptible for the ovine herpesvirus-2 (OvHV-2) causing the sheep-associated form of MCF (SA-MCF). This report describes the first case of possibly caprine-associated malignant catarrhal fever symptoms in a domestic water buffalo in Switzerland. Case presentation The buffalo cow presented with persistent fever, dyspnoea, nasal bleeding and haematuria. Despite symptomatic therapy, the buffalo died and was submitted to post mortem examination. Major findings were an abomasal ulceration, a mild haemorrhagic cystitis and multifocal haemorrhages on the epicardium and on serosal and mucosal surfaces. Eyes and oral cavity were not affected. Histopathology revealed a mild to moderate lymphohistiocytic vasculitis limited to the brain and the urinary bladder. Although these findings are typical for MCF, OvHV-2 DNA was not detected in peripheral blood lymphocytes or in paraffin-embedded brain, using an OvHV-2 specific real time PCR. With the aid of a panherpesvirus PCR, a caprine herpesvirus-2 (CpHV-2) sequence could be amplified from both samples. Conclusions To our knowledge, this is the first report of malignant catarrhal fever in the subfamily Bovinae, where the presence of CpHV-2 could be demonstrated. The etiological context has yet to be evaluated. PMID:22132808

  1. Sediment dynamic at the water-sediment interface of the Thau Lagoon (S. France) from seasonal to century time scales using radiogenic and comosgenic nuclides

    NASA Astrophysics Data System (ADS)

    Jouanneau, J.-M.; Schmidt, S.; Weber, O.; Lecroart, P.; Radakovitch, O.; Gilbert, F.; Jezequel, D.

    2003-04-01

    Among the factors disturbing the sedimentary record the most important are massive sediment displacement, erosion, bioturbation, and human activities. As a part of the PNEC supported Microbent programme, we investigated sedimentation processes to determine sediment deposit/erosion cycle at the water-sediment interface in relation with these potential perturbations. The investigated area is the Thau Lagoon, located in the south of France and strongly influenced by human activities (Sete industrial harbour, oyster farming). Two main sites were investigated: C4 in the middle of the lagoon in order to have a reference site, C5 nearby oyster farming. Sediment cores, up to 50cm in length, were collected in Dec. 2001, April, July and August 2002. Interface sediments have been studied using classical sedimentological parameters (radiography, grain size distribution) and analysis of the radionuclides Th-234, Be-7, Pb-210 and Cs-137 (gamma and alpha spectrometry). On a century time scale, 210Pb and 137Cs profiles indicate well defined sedimentation rates at both sites (around 0.2 0.3 cm per year). Nevertheless at the central site, C4, cores seem to register episodic changes in mean granulometry, presenting recurrently peaks. The upper 10 cm of Pb-210 profiles at site C5 exhibit a mixed layer associated with coarser sediments: these could be in relation with biological or dredging activity. On a seasonal time scale, Th-234 and Be-7 both show seasonal variations in activities and in penetration within the sediment. As these radionuclides are mainly carried by the fine particles, such variations must reflected associated variations of silt content of surface sediments. Fine sediment accumulation is a balance between deposition (settling, bioaccumulation) and erosion. Summer period seems to correspond to the most favourable season for deposition for the Thau lagoon. This study clearly illustrates the interest of radionuclides of different input and half-life to describe in details processes like sediment accumulation, bioturbation, erosion / deposition at different time scales.

  2. Sediment and water toxicity evaluations for the Clinch River ecological risk assessment

    SciTech Connect

    Gonzalez, A.M.; Phipps, T.L.; Kszos, L.A.

    1995-12-31

    The sediment and surface water at three sites in the Clinch River and six sites in Poplar Creek were evaluated by means of toxicity tests with aquatic organisms. The results of these tests were used as one of the lines of evidence in an assessment of ecological risk due to contaminants, transported from the Oak Ridge Reservation, to the off-site sediment and water environment. Results from a suite of six whole sediment, elutriate and pore water toxicity tests were summarized in terms of survival (Hyalella azteca, Daphnia magna, Anodonta imbecillis, Ceriodaphnia dubia), fecundity (Daphnia magna) or light output reduction (Microtox{reg_sign}). Results from the water toxicity tests were summarized in terms of reduction in survival or fecundity of C. dubia, and survival or growth of Pimephales promelas. Toxicity test results (covering a period of about 1 6 months) showed little difference between reference site media and media from sites of concern. They also showed no strong spatial or temporal response pattern. These results are further supported by the presence of indigenous Chironomus and Hexagenia spp. in the sediment samples. Toxicity results will be discussed with respect to three issues. Two criteria were used to define significant differences between reference sites and sites of concern: a difference of 20%, and statistical significance at a = 0.05. Secondly, the relevance of comparing mean responses to control vs. reference site will be discussed. Lastly, toxicity results are consistent with site characterization information which suggest that contaminants of concern in sediment are buried under clean sediment, effectively isolating the material from potential human or ecological exposure.

  3. Water and sediment quality assessment of the Axios River and its coastal environment

    NASA Astrophysics Data System (ADS)

    Karageorgis, A. P.; Nikolaidis, N. P.; Karamanos, H.; Skoulikidis, N.

    2003-11-01

    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.

  4. Monitoring the impact of urban effluents on mineral contents of water and sediments of four sites of the river Ravi, Lahore.

    PubMed

    Shakir, Hafiz Abdullah; Qazi, Javed Iqbal; Chaudhry, Abdul Shakoor

    2013-12-01

    We assessed the impact of urban effluents on the concentrations of selected minerals (Cd, Cr, Cu, Fe, Pb, Zn, Mn, Ni, and Hg) in river Ravi before and after its passage through Lahore city. Water and sediment samples were collected from three lowly to highly polluted downstream sites (Shahdera (B), Sunder (C), and Balloki (D)) alongside the least polluted upstream site (Siphon (A)) during high and low river flow seasons. All the mineral concentrations increased up to site C but stabilized at site D, showing some recovery as compared to the third sampling site. The trend of mean mineral concentration was significantly higher during the low than the high flow season at all the sites. The mean Hg concentrations approached 0.14 and 0.12 mg/l at site A which increased (%) up to 107 and 25% at site B, 1,700 and 1,317% at site C, and 1,185 and 1,177% at site D during low and high river flows, respectively. All mineral concentrations were much higher in the sediment than the water samples. Mean Cd (917%), Cr (461%), Cu (300%), Fe (254%), Pb (179%), Zn (170%), Mn (723%), Ni (853%), and Hg (1,699%) concentrations were higher in riverbed sediments sampled from site C in comparison with the sample collected at site A during low flow season. The domestic and industrial discharges from Lahore city have created undesirable water qualities during the low river flow season. As majority of the mineral levels in the river Ravi were higher than the permissible and safe levels, this is of immediate concern for riverine fish consumers and the users of water for recreation and even irrigation. The use of these waters may pose health risks, and therefore, urgent intervention strategies are needed to minimize river water pollution and its impact on fish-consuming communities of this study area and beyond. PMID:23793567

  5. Aluminum forms in stream sediment: Relation to bedrock geology and water chemistry

    SciTech Connect

    Turner, R.R.; Bogle, M.A.; Zeiler, M.A.; Mulholland, P.J.; Elwood, J.W.; Cook, R.B.

    1987-01-01

    Longitudinal gradients in sediment and water chemistry were characterized in a high elevation stream in the southern Appalachian Mountains, USA, to elucidate the geochemical behavior of aluminum across gradients in pH (4.5 to 6.5) and elevation (1120 to 1895 m). Observed gradients are driven in part by the presence of pyritic bedrock, which occurs at higher elevations and yields acidity when exposed to oxidation by landslide activity. Exchangeable Al in sediment (estimated using potassium chloride) varied in response to monomeric Al in streamwater and thus decreased downstream. Organic Al in sediment (estimated using sodium pyrophosphate) did not vary in proportion to the organic carbon content of sediment. Amorphous Al in sediment (estimated as the difference between oxalate- and pyrophosphate-extractable Al) and Al extractable with acidified streamwater (pH 4.5) was lowest at the more acidic sites. These results suggest that increases in soluble Al in downstream reaches during episodic pH depressions could be due in part to the release of adsorbed and/or precipitated Al in sediment.

  6. Chronic toxicity of tire and road wear particles to water- and sediment-dwelling organisms.

    PubMed

    Panko, Julie M; Kreider, Marisa L; McAtee, Britt L; Marwood, Christopher

    2013-01-01

    Tire and road wear particles (TRWP) consist of a complex mixture of rubber, and pavement released from tires during use on road surfaces. Subsequent transport of the TRWP into freshwater sediments has raised some concern about the potential adverse effects on aquatic organisms. Previous studies have shown some potential for toxicity for tread particles, however, toxicity studies of TRWP collected from a road simulator system revealed no acute toxicity to green algae, daphnids, or fathead minnows at concentrations up to 10,000 mg/kg under conditions representative of receiving water bodies. In this study, the chronic toxicity of TRWP was evaluated in four aquatic species. Test animals were exposed to whole sediment spiked with TRWP at concentrations up to 10,000 mg/kg sediment or elutriates from spiked sediment. Exposure to TRWP spiked sediment caused mild growth inhibition in Chironomus dilutus but had no adverse effect on growth or reproduction in Hyalella azteca. Exposure to TRWP elutriates resulted in slightly diminished survival in larval Pimephales promelas but had no adverse effect on growth or reproduction in Ceriodaphnia dubia. No other endpoints in these species were affected. These results, together with previous studies demonstrating no acute toxicity of TRWP, indicate that under typical exposure conditions TRWP in sediments pose a low risk of toxicity to aquatic organisms. PMID:23001428

  7. Environmental modelling in the Gulf of Cadiz: heavy metal distributions in water and sediments.

    PubMed

    Periez, R

    2009-05-01

    The Gulf of Cadiz (GoC) connects the Atlantic Ocean and the Mediterranean Sea. An environmental study of the GoC is carried out through numerical modelling. First, a 3D baroclinic model is used to obtain the residual circulation and a 2D barotropic model is applied to calculate tides. The results of these models are used by a 3D sediment transport model which provides suspended matter concentrations and sedimentation rates in the GoC. Then heavy metal dispersion patterns are investigated using a 3D model which includes water-sediment metal interactions and uses the outputs of the hydrodynamic and sediment transport models. The metal transport model has been applied to simulate the dispersion of Zn, Cu and Ni introduced into the GoC from three rivers draining the Iberian Pyrite Belt, in the southern Iberian Peninsula. Results from the hydrodynamic, sediment and metal transport models have been compared with measurements in the GoC. In particular, the contamination of sediments collected along the southern coast of Spain is well reproduced by the model. Metal plumes reach the Strait of Gibraltar, thus the three rivers constitute a source of pollutants into the Mediterranean Sea. PMID:19246075

  8. Transport of anthropogenic uranium from sediments to surface waters during episodic storm events

    SciTech Connect

    Batson, V.L. |; Bertsch, P.M.; Herbert, B.E.

    1996-09-01

    Remobilization of sediment-associated uranium (U) from contaminated floodplain sediments to a stream adjacent to a nuclear weapons processing facility during episodic rain events was investigated. In addition, U solid phase associations in suspended sediments were assessed by a sequential chemical extraction procedure to gauge U chemical lability. Mass flux estimates determined from base flow measurements potentially underestimate the amount of U transported from contaminated terrestrial sources to surface water systems. Erosional processes can effectively mobilize sediment-associated contaminants during storms or flooding. During the various storm events measured, approximately 1500 to 2800% more U was exported to Upper Three Runs Creek (UTRC) relative to base flow measurements. Sequential extraction results suggest the suspended a sediment load transports the bulk of U in labile forms predominantly as acid soluble (specifically adsorbed), MnO{sub 2} occluded and organically bound phases. This implies that U may be available to the ecosystem under a range of environmental conditions likely to be encountered within depositional environments (e.g., Eh and pH) or as a result of industrial processes. This study demonstrates the need to evaluate contaminant transport during storm events from exposed contaminated sediments, or from industrial waste stockpiles subject to erosion. 49 refs., 5 figs., 3 tabs.

  9. Increased dissolved oxygen in Pacific intermediate waters due to lower rates of carbon oxidation in sediments.

    PubMed

    Stott, L D; Berelson, W; Douglas, R; Gorsline, D

    2000-09-21

    Concentrations of dissolved oxygen in the ocean seem to correlate well with climate instabilities over the past 100,000 years. For example, the concentration of dissolved oxygen in Pacific intermediate waters was considerably higher during Pleistocene glacial periods than it is today. This has been inferred from the presence of bioturbated sediments, implying that oxygen levels were sufficient for burrowing organisms to live. Today, basins in the northeastern Pacific Ocean are floored by laminated sediments implying lower oxygen levels, which may be explained by reduced ventilation. Here we report a recent return to bioturbated sediments in the northeastern Pacific Ocean since the late 1970s. From the carbon isotope composition of benthic foraminifers living in the sediment, we infer a twofold decrease in the carbon oxidation rate occurring within sediments, equivalent to an increase in dissolved oxygen concentration of 15-20 micromoles per litre. These changes, at the edges of the Santa Barbara, Santa Monica and Alfonso basins, are coincident with a change in North Pacific climate which has reduced upwelling by 20-30% and increased sea surface temperatures by 1.5-3 degrees C. This suggests that climate effects on surface productivity, reducing the supply organic matter to sediments, may have had a greater effect on benthic oxygen levels than changes in ocean circulation patterns. PMID:11014190

  10. Sediment quality in near coastal waters of the Gulf of Mexico: influence of Hurricane Katrina.

    PubMed

    Macauley, John M; Smith, Lisa M; Harwell, Linda C; Benson, William H

    2010-07-01

    The results of the present study represent a synoptic analysis of sediment quality in coastal waters of Lake Pontchartrain and Mississippi Sound two months after the landfall of Hurricane Katrina. Posthurricane conditions were compared to prehurricane (2000-2004) conditions, for sediment quality data. There were no exceedances of effects range median (ERM) sediment quality guideline values for chemical contaminants in any of the sediment samples collected from the Lake Pontchartrain or the Mississippi Sound study areas following the hurricane. Lower threshold effects range low (ERL) values were exceeded for As, Cd, and Ni at several stations in both survey areas, similar to levels of contamination observed prior to the hurricane. The comparison of sediment quality indicators before and after the hurricane suggests considerable stability of these systems with respect to short-term ecological impacts. Although other studies have shown storm-related changes could be detected (e.g., effects on benthic communities associated with shifts in salinity), there were no indications of widespread sediment contamination. PMID:20821587

  11. ASSESSING WATER QUALITY CHANGES IN THE LAKES OF THE NORTHEASTERN UNITED STATES USING SEDIMENT DIATOMS

    EPA Science Inventory

    Diatom assemblages were selected as indicators of lake condition and to assess historical lake water quality changes in 257 lakes in the northeastern United States. The "top" (surface sediments, present-day) and "bottom" (generally from >30 cm deep, representing historical condit...

  12. 30 CFR 77.216 - Water, sediment, or slurry impoundments and impounding structures; general.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... WORK AREAS OF UNDERGROUND COAL MINES Surface Installations § 77.216 Water, sediment, or slurry... approved by the District Manager prior to the beginning of any work associated with construction of the... structure; or (3) As determined by the District Manager, present a hazard to coal miners. (b) Plans for...

  13. 30 CFR 77.216-3 - Water, sediment, or slurry impoundments and impounding structures; inspection requirements...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND... impounding structures; inspection requirements; correction of hazards; program requirements. 77.216-3 Section... structures; inspection requirements; correction of hazards; program requirements. (a) All water, sediment,...

  14. Dissipation of glyphosate and aminomethylphosphonic acid in water and sediment of two Canadian prairie wetlands.

    PubMed

    Degenhardt, Dani; Humphries, David; Cessna, Allan J; Messing, Paul; Badiou, Pascal H; Raina, Renata; Farenhorst, Annemieke; Pennock, Dan J

    2012-01-01

    Glyphosate [N-(phosphonomethyl)glycine] is the active ingredient of several herbicide products first registered for use in 1974 under the tradename Roundup. The use of glyphosate-based herbicides has increased dramatically over the last two decades particularly in association with the adoption of glyphosate-tolerant crops. Glyphosate has been detected in a range of surface waters but this is the first study to monitor its fate in prairie wetlands situated in agricultural fields. An ephemeral wetland (E) and a semi-permanent wetland (SP) were each divided into halves using a polyvinyl curtain. One half of each wetland was fortified with glyphosate with the added mass simulating an accidental direct overspray. Glyphosate dissipated rapidly in the water column of the two prairie wetlands studied (DT(50) values of 1.3 and 4.8 d) which may effectively reduce the impact of exposure of aquatic biota to the herbicide. Degradation of glyphosate to its major metabolite aminomethylphosphonic acid (AMPA) and sorption of the herbicide to bottom sediment were more important pathways for the dissipation of glyphosate from the water column than movement of the herbicide with infiltrating water. Presently, we are not aware of any Canadian guidelines for glyphosate residues in sediment of aquatic ecosystems. Since a substantial portion of glyphosate entering prairie wetlands will become associated with bottom sediments, particularly in ephemeral wetlands, guidelines would need to be developed to assess the protection of organisms that spend all or part of their lifecycle in sediment. PMID:22560025