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Sample records for groundwater treatment unit

  1. ALTERNATIVE REMEDIATION TECHNOLOGY STUDY FOR GROUNDWATER TREATMENT AT 200-PO-1 OPERABLE UNIT AT HANFORD SITE

    SciTech Connect

    DADO MA

    2008-07-31

    This study focuses on the remediation methods and technologies applicable for use at 200-PO-I Groundwater Operable Unit (OU) at the Hanford Site. The 200-PO-I Groundwater au requires groundwater remediation because of the existence of contaminants of potential concern (COPC). A screening was conducted on alternative technologies and methods of remediation to determine which show the most potential for remediation of groundwater contaminants. The possible technologies were screened to determine which would be suggested for further study and which were not applicable for groundwater remediation. COPCs determined by the Hanford Site groundwater monitoring were grouped into categories based on properties linking them by remediation methods applicable to each COPC group. The screening considered the following criteria. (1) Determine if the suggested method or technology can be used for the specific contaminants found in groundwater and if the technology can be applied at the 200-PO-I Groundwater au, based on physical characteristics such as geology and depth to groundwater. (2) Evaluate screened technologies based on testing and development stages, effectiveness, implementability, cost, and time. This report documents the results of an intern research project conducted by Mathew Dado for Central Plateau Remediation in the Soil and Groundwater Remediation Project. The study was conducted under the technical supervision of Gloria Cummins and management supervision of Theresa Bergman and Becky Austin.

  2. LITERATURE SURVEY FOR GROUNDWATER TREATMENT OPTIONS FOR NITRATE IODINE-129 AND URANIUM 200-ZP-1 OPERABLE UNIT HANFORD SITE

    SciTech Connect

    BYRNES ME

    2008-06-05

    This literature review presents treatment options for nitrate, iodine-129, and uranium, which are present in groundwater at the 200-ZP-I Groundwater Operable Unit (OU) within the 200 West Area of the Hanford Site. The objective of this review is to determine available methods to treat or sequester these contaminants in place (i.e., in situ) or to pump-and-treat the groundwater aboveground (i.e., ex situ). This review has been conducted with emphasis on commercially available or field-tested technologies, but theoretical studies have, in some cases, been considered when no published field data exist. The initial scope of this literature review included only nitrate and iodine-I 29, but it was later expanded to include uranium. The focus of the literature review was weighted toward researching methods for treatment of nitrate and iodine-129 over uranium because of the relatively greater impact of those compounds identified at the 200-ZP-I OU.

  3. Situ treatment of contaminated groundwater

    DOEpatents

    McNab, Jr., Walt W.; Ruiz, Roberto; Pico, Tristan M.

    2001-01-01

    A system for treating dissolved halogenated organic compounds in groundwater that relies upon electrolytically-generated hydrogen to chemically reduce the halogenated compounds in the presence of a suitable catalyst. A direct current is placed across at least a pair, or an array, of electrodes which are housed within groundwater wells so that hydrogen is generated at the cathode and oxygen at the anode. A pump is located within the well housing in which the cathode(s) is(are) located and draws in groundwater where it is hydrogenated via electrolysis, passes through a well-bore treatment unit, and then transported to the anode well(s) for reinjection into the ground. The well-bore treatment involves a permeable cylinder located in the well bore and containing a packed bed of catalyst material that facilitates the reductive dehalogenation of the halogenated organic compounds by hydrogen into environmentally benign species such as ethane and methane. Also, electro-osmatic transport of contaminants toward the cathode also contributes to contaminant mass removal. The only above ground equipment required are the transfer pipes and a direct circuit power supply for the electrodes. The electrode wells in an array may be used in pairs or one anode well may be used with a plurality of cathode wells. The DC current flow between electrode wells may be periodically reversed which controls the formation of mineral deposits in the alkaline cathode well-bore water, as well as to help rejuvenate the catalysis.

  4. Groundwater Governance in the United States: Common Priorities and Challenges.

    PubMed

    Megdal, Sharon B; Gerlak, Andrea K; Varady, Robert G; Huang, Ling-Yee

    2015-01-01

    Groundwater is a critical component of the water supply for agriculture, urban areas, industry, and ecosystems, but managing it is a challenge because groundwater is difficult to map, quantify, and evaluate. Until recently, study and assessment of governance of this water resource has been largely neglected. A survey was developed to query state agency officials about the extent and scope of groundwater use, groundwater laws and regulations, and groundwater tools and strategies. Survey responses revealed key findings: states' legal frameworks for groundwater differ widely in recognizing the hydrologic connection between surface water and groundwater, the needs of groundwater-dependent ecosystems, and the protection of groundwater quality; states reported a range in capacity to enforce groundwater responsibilities; and states have also experienced substantial changes in groundwater governance in the past few decades. Overall, groundwater governance across the United States is fragmented. States nevertheless identified three common priorities for groundwater governance: water quality and contamination, conflicts between users, and declining groundwater levels. This survey represents an initial step in a broader, continuing effort to characterize groundwater governance practices in the United States. PMID:25406503

  5. In Situ Treatment of Chromium-Contaminated Groundwater

    SciTech Connect

    Fruchter, Jonathan S. )

    2002-12-01

    In Situ Treatment of Chromate Contaminated Groundwater Jonathan S. Fruchter Pacific Northwest National Laboratory Abstract of paper published in Environmental Science and Technology, 2002 Although not as common as solvent or fuel products contamination, chromate (chromium (VI)) contamination of groundwater is relatively widespread. Chromate has a variety of industrial uses, including chrome plating, steel making, and use as a corrosion inhibitor, wood preservative, well-drilling fluid additive, biocide, and as a pigment in paints and primers. EPA has estimated that as many as 1300 sites in the United States may have groundwater contaminated with chromate. The paper discusses a number of approaches to in situ treatment of chromate contamination in groundwater aquifers. The approaches include various types of chemical treatments, biological treatments and natural attenuation. The strengths and weaknesses of each method are discussed and compared. Field examples of two types of chemical treatment, in situ redox manipulation and chemically enhanced pump and treat are presented. It is concluded that in situ methods show promise, but can be difficult to implement due to site-specific conditions and limited long-term experience with these methods. As more performance and cost data are acquired for the demonstrations that are ongoing, and continuing research increases our understanding of subsurface processes, in situ treatment methods for chromium (VI) contamination in groundwater should gain wider acceptance.

  6. Oxidative particle mixtures for groundwater treatment

    DOEpatents

    Siegrist, Robert L.; Murdoch, Lawrence C.

    2000-01-01

    The invention is a method and a composition of a mixture for degradation and immobilization of contaminants in soil and groundwater. The oxidative particle mixture and method includes providing a material having a minimal volume of free water, mixing at least one inorganic oxidative chemical in a granular form with a carrier fluid containing a fine grained inorganic hydrophilic compound and injecting the resulting mixture into the subsurface. The granular form of the inorganic oxidative chemical dissolves within the areas of injection, and the oxidative ions move by diffusion and/or advection, therefore extending the treatment zone over a wider area than the injection area. The organic contaminants in the soil and groundwater are degraded by the oxidative ions, which form solid byproducts that can sorb significant amounts of inorganic contaminants, metals, and radionuclides for in situ treatment and immobilization of contaminants. The method and composition of the oxidative particle mixture for long-term treatment and immobilization of contaminants in soil and groundwater provides for a reduction in toxicity of contaminants in a subsurface area of contamination without the need for continued injection of treatment material, or for movement of the contaminants, or without the need for continuous pumping of groundwater through the treatment zone, or removal of groundwater from the subsurface area of contamination.

  7. Family Treatment Unit.

    ERIC Educational Resources Information Center

    Sawicki, Donna

    The document describes the Family Treatment Unit, a demonstration program to provide a variety of family treatment services to status offenders (11 to 17 years old) and their families. The goals of the program are: (1) to provide family services to families of status offenders; (2) to maintain status offenders in their natural homes by…

  8. Nitrate in groundwater of the United States, 1991-2003

    USGS Publications Warehouse

    Burow, Karen R.; Nolan, Bernard T.; Rupert, Michael G.; Dubrovsky, Neil M.

    2010-01-01

    An assessment of nitrate concentrations in groundwater in the United States indicates that concentrations are highest in shallow, oxic groundwater beneath areas with high N inputs. During 1991-2003, 5101 wells were sampled in 51 study areas throughout the U.S. as part of the U.S. Geological Survey National Water-Quality Assessment (NAWQA) program. The well networks reflect the existing used resource represented by domestic wells in major aquifers (major aquifer studies), and recently recharged groundwater beneath dominant land-surface activities (land-use studies). Nitrate concentrations were highest in shallow groundwater beneath agricultural land use in areas with well-drained soils and oxic geochemical conditions. Nitrate concentrations were lowest in deep groundwater where groundwater is reduced, or where groundwater is older and hence concentrations reflect historically low N application rates. Classification and regression tree analysis was used to identify the relative importance of N inputs, biogeochemical processes, and physical aquifer properties in explaining nitrate concentrations in groundwater. Factors ranked by reduction in sum of squares indicate that dissolved iron concentrations explained most of the variation in groundwater nitrate concentration, followed by manganese, calcium, farm N fertilizer inputs, percent well-drained soils, and dissolved oxygen. Overall, nitrate concentrations in groundwater are most significantly affected by redox conditions, followed by nonpoint-source N inputs. Other water-quality indicators and physical variables had a secondary influence on nitrate concentrations.

  9. Groundwater Treatment at the Fernald Preserve: Status and Path Forward for the Water Treatment Facility - 12320

    SciTech Connect

    Powel, J.; Hertel, B.; Glassmeyer, C.; Broberg, K.

    2012-07-01

    Operating a water treatment facility at the Fernald Preserve in Cincinnati, Ohio-to support groundwater remediation and other wastewater treatment needs-has become increasingly unnecessary. The Fernald Preserve became a U.S. Department of Energy Office of Legacy Management (LM) site in November 2006, once most of the Comprehensive Environmental Response, Compensation, and Liability Act environmental remediation and site restoration had been completed. Groundwater remediation is anticipated to continue beyond 2020. A portion of the wastewater treatment facility that operated during the CERCLA cleanup continued to operate after the site was transferred to LM, to support the remaining groundwater remediation effort. The treatment facility handles the site's remaining water treatment needs (for groundwater, storm water, and wastewater) as necessary, to ensure that uranium discharge limits specified in the Operable Unit 5 Record of Decision are met. As anticipated, the need to treat groundwater to meet uranium discharge limits has greatly diminished over the last several years. Data indicate that the groundwater treatment facility is no longer needed to support the ongoing aquifer remediation effort. (authors)

  10. Potassium ferrate treatment of RFETS` contaminated groundwater

    SciTech Connect

    1995-01-01

    The potassium ferrate treatment study of Rocky Flats Environmental Technology Site (RFETS) groundwater was performed under the Sitewide Treatability Studies Program (STSP). This study was undertaken to determine the effectiveness of potassium ferrate in a water treatment system to remove the contaminants of concern (COCS) from groundwater at the RFETS. Potassium ferrate is a simple salt where the iron is in the plus six valence state. It is the iron at the plus six valence state (Fe {sup +6}) that makes it an unique water treatment chemical, especially in waters where the pH is greater than seven. In basic solutions where the solubility of the oxides/hydroxides of many of the COCs is low, solids are formed as the pH is raised. By using ferrate these solids are agglomerated so they can be effectively removed by sedimentation in conventional water treatment equipment. The objective of this study was to determine the quality of water after treatment with potassium ferrate and to determine if the Colorado Water Quality Control Commission (CWQCC) discharge limits for the COCs listed in Table 1.0-1 could be met. Radionuclides in the groundwater were of special concern.

  11. Chlorine-36 in groundwater of the United States: Empirical data

    USGS Publications Warehouse

    Davis, S.N.; Moysey, S.; Cecil, L.D.; Zreda, M.

    2003-01-01

    Natural production of the radionuclide chlorine-36 (36Cl) has provided a valuable tracer for groundwater studies. The nuclear industry, especially the testing of thermonuclear weapons, has also produced large amounts of 36Cl that can be detected in many samples of groundwater. In order to be most useful in hydrologic studies, the natural production prior to 1952 should be distinguished from more recent artificial sources. The object of this study was to reconstruct the probable preanthropogenic levels of 36Cl in groundwater in the United States. Although significant local variations exist, they are superimposed on a broad regional pattern of 36Cl/Cl ratios in the United States. Owing to the influence of atmospherically transported ocean salt, natural ratios of 36Cl/total Cl are lowest near the coast and increase to a maximum in the central Rocky Mountains of the United States.

  12. Chlorinated solvents in groundwater of the United States

    USGS Publications Warehouse

    Moran, M.J.; Zogorski, J.S.; Squillace, P.J.

    2007-01-01

    Four chlorinated solvents-methylene chloride, perchloroethene (PCE), 1,1,1-trichloroethane, and trichloroethene (TCE)-were analyzed in samples of groundwater taken throughout the conterminous United States by the U.S. Geological Survey. The samples were collected between 1985 and 2002 from more than 5,000 wells. Of 55 volatile organic compounds (VOCs) analyzed in groundwater samples, solvents were among the most frequently detected. Mixtures of solvents in groundwater were common and may be the result of common usage of solvents or degradation of one solvent to another. Relative to other VOCs with Maximum Contaminant Levels (MCLs), PCE and TCE ranked high in terms of the frequencies of concentrations greater than or near MCLs. The probability of occurrence of solvents in groundwater was associated with dissolved oxygen content of groundwater, sources such as urban land use and population density, and hydraulic properties of the aquifer. The results reinforce the importance of understanding the redox conditions of aquifers and the hydraulic properties of the saturated and vadose zones in determining the intrinsic susceptibility of groundwater to contamination by solvents. The results also reinforce the importance of controlling sources of solvents to groundwater. ?? 2007 American Chemical Society.

  13. Groundwater Treatment at SRS: An Innovative Approach

    SciTech Connect

    Jorque, M.A.; Golshir, G.H.; Davis, B.

    1998-03-01

    The SRS is located in southwestern South Carolina, occupying an almost circular area of approximately 800 km{sub 2} within Aiken, Barnwell, and Allendale counties. The site lies approximately 36 km southeast of Augusta, Georgia, and is bounded by the Savannah River along its southwestern border. Prior to the establishment of the SRS in 1952, the area was largely a rural agricultural community. As part of the defense complex, the SRS produced special nuclear materials for the national defense. From 1955 until 1988, unlined earthen basins were used to dispose of wastewater from the SRS separations facilities located in the F and H areas. Approximately 300 million liters of wastewater was transported annually from the process area through underground piping to the basins. The wastewater was allowed to evaporate and to seep into the underlying formations. There were three basins in the F-Area covering a total of about 3 hectares; while the H-Area was served by four basins covering about 6 hectares. The seepage basins closure was started in 1989 and SCDHEC certified the closures as completed in 1991. Groundwater monitoring conducted in accordance with the provisions of the RCRA Permits determined that the underlying hydrogeologic units were contaminated by tritium, radioactive metals (primarily Cesium{sup 137}, Strontium{sup 90}, and Uranium{sup 235}), nitrate and heavy metals, some of which are defined as hazardous by RCRA. Under the terms and conditions of the RCRA Post-Closure Permits, it was necessary to remediate the contaminated groundwater plumes.

  14. Groundwater Treatment at SRS: An Innovative Approach

    SciTech Connect

    Jorque, M.A.; Golshir, G.H.; Davis, B.

    1998-03-01

    The SRS is located in southwestern South Carolina, occupying an almost circular area of approximately 800 km2 within Aiken, Barnwell, and Allendale counties. The site lies approximately 36 km southeast of Augusta, Georgia, and is bounded by the Savannah River along its southwestern border. Prior to the establishment of the SRS in 1952, the area was largely a rural agricultural community. As part of the defense complex, the SRS produced special nuclear materials for the national defense.From 1955 until 1988, unlined earthen basins were used to dispose of wastewater from the SRS separations facilities located in the F and H areas. Approximately 300 million liters of wastewater was transported annually from the process area through underground piping to the basins. The wastewater was allowed to evaporate and to seep into the underlying formations. There were three basins in the F-Area covering a total of about 3 hectares; while the H-Area was served by four basins covering about 6 hectares. The seepage basins closure was started in 1989 and SCDHEC certified the closures as completed in 1991.Groundwater monitoring conducted in accordance with the provisions of the RCRA Permits determined that the underlying hydrogeologic units were contaminated by tritium, radioactive metals (primarily Cesium 137, Strontium 90, and Uranium 235), nitrate and heavy metals, some of which are defined as hazardous by RCRA. Under the terms and conditions of the RCRA Post- Closure Permits, it was necessary to remediate the contaminated groundwater plumes.

  15. Groundwater Monitoring Report Project Shoal Area, Corrective Action Unit 447

    SciTech Connect

    2008-01-01

    This report presents the 2007 groundwater monitoring results collected by the U.S. Department of Energy (DOE) Office of Legacy Management (LM) at the Project Shoal Area (PSA) Corrective Action Unit (CAU) 447 located in Churchill County, Nevada. Responsibility for the environmental site restoration of the PSA was transferred from the DOE Office of Environmental Management (DOE-EM) to DOE-LM on October 1, 2006. Requirements for CAU 447, as specified in the Federal Facility Agreement and Consent Order (FFACO 2005) entered into by DOE, the U.S. Department of Defense (DOD), and the State of Nevada, includes groundwater monitoring in support of site closure. This is the first groundwater monitoring report prepared by DOE-LM for the PSA.

  16. Virtual groundwater transfers from overexploited aquifers in the United States

    NASA Astrophysics Data System (ADS)

    Marston, L.; Konar, M.; Cai, X.; Troy, T.

    2015-12-01

    The High Plains, Mississippi Embayment, and Central Valley aquifer systems within the United States are currently being overexploited for irrigation water supplies. The unsustainable use of groundwater resources in all three aquifer systems intensified from 2000 to 2008, making it imperative that we understand the consumptive processes and forces of demand that are driving their depletion. To this end, we quantify and track agricultural virtual groundwater transfers from these overexploited aquifer systems to their final destination. Specifically, we determine which US metropolitan areas, US states, and international export destinations are currently the largest consumers of these critical aquifers. We draw upon US government data on agricultural production, irrigation, and domestic food flows, as well as modeled estimates of agricultural virtual water contents to quantify domestic transfers. Additionally, we use US port-level trade data to trace international exports from these aquifers. In 2007, virtual groundwater transfers from the High Plains, Mississippi Embayment, and Central Valley aquifer systems totaled 17.93 km3, 9.18 km3, and 6.81 km3, respectively, which is comparable to the capacity of Lake Mead (35.7 km3), the largest surface reservoir in the United States. The vast majority (91%) of virtual groundwater transfers remains within the United States. Importantly, the cereals produced by these overexploited aquifers are critical to US food security (contributing 18.5% to domestic cereal supply). Notably, Japan relies upon cereals produced by these overexploited aquifers for 9.2% of its domestic cereal supply. These results highlight the need to understand the teleconnections between distant food demands and local agricultural water use.

  17. Virtual groundwater transfers from overexploited aquifers in the United States.

    PubMed

    Marston, Landon; Konar, Megan; Cai, Ximing; Troy, Tara J

    2015-07-14

    The High Plains, Mississippi Embayment, and Central Valley aquifer systems within the United States are currently being overexploited for irrigation water supplies. The unsustainable use of groundwater resources in all three aquifer systems intensified from 2000 to 2008, making it imperative that we understand the consumptive processes and forces of demand that are driving their depletion. To this end, we quantify and track agricultural virtual groundwater transfers from these overexploited aquifer systems to their final destination. Specifically, we determine which US metropolitan areas, US states, and international export destinations are currently the largest consumers of these critical aquifers. We draw upon US government data on agricultural production, irrigation, and domestic food flows, as well as modeled estimates of agricultural virtual water contents to quantify domestic transfers. Additionally, we use US port-level trade data to trace international exports from these aquifers. In 2007, virtual groundwater transfers from the High Plains, Mississippi Embayment, and Central Valley aquifer systems totaled 17.93 km(3), 9.18 km(3), and 6.81 km(3), respectively, which is comparable to the capacity of Lake Mead (35.7 km(3)), the largest surface reservoir in the United States. The vast majority (91%) of virtual groundwater transfers remains within the United States. Importantly, the cereals produced by these overexploited aquifers are critical to US food security (contributing 18.5% to domestic cereal supply). Notably, Japan relies upon cereals produced by these overexploited aquifers for 9.2% of its domestic cereal supply. These results highlight the need to understand the teleconnections between distant food demands and local agricultural water use. PMID:26124137

  18. Virtual groundwater transfers from overexploited aquifers in the United States

    PubMed Central

    Marston, Landon; Konar, Megan; Cai, Ximing; Troy, Tara J.

    2015-01-01

    The High Plains, Mississippi Embayment, and Central Valley aquifer systems within the United States are currently being overexploited for irrigation water supplies. The unsustainable use of groundwater resources in all three aquifer systems intensified from 2000 to 2008, making it imperative that we understand the consumptive processes and forces of demand that are driving their depletion. To this end, we quantify and track agricultural virtual groundwater transfers from these overexploited aquifer systems to their final destination. Specifically, we determine which US metropolitan areas, US states, and international export destinations are currently the largest consumers of these critical aquifers. We draw upon US government data on agricultural production, irrigation, and domestic food flows, as well as modeled estimates of agricultural virtual water contents to quantify domestic transfers. Additionally, we use US port-level trade data to trace international exports from these aquifers. In 2007, virtual groundwater transfers from the High Plains, Mississippi Embayment, and Central Valley aquifer systems totaled 17.93 km3, 9.18 km3, and 6.81 km3, respectively, which is comparable to the capacity of Lake Mead (35.7 km3), the largest surface reservoir in the United States. The vast majority (91%) of virtual groundwater transfers remains within the United States. Importantly, the cereals produced by these overexploited aquifers are critical to US food security (contributing 18.5% to domestic cereal supply). Notably, Japan relies upon cereals produced by these overexploited aquifers for 9.2% of its domestic cereal supply. These results highlight the need to understand the teleconnections between distant food demands and local agricultural water use. PMID:26124137

  19. Performance assessment techniques for groundwater recovery and treatment systems

    SciTech Connect

    Kirkpatrick, G.L.

    1993-03-01

    Groundwater recovery and treatment (pump and treat systems) continue to be the most commonly selected remedial technology for groundwater restoration and protection programs at hazardous waste sites and RCRA facilities nationwide. Implementing a typical groundwater recovery and treatment system includes the initial assessment of groundwater quality, characterizing aquifer hydrodynamics, recovery system design, system installation, testing, permitting, and operation and maintenance. This paper focuses on methods used to assess the long-term efficiency of a pump and treat system. Regulatory agencies and industry alike are sensitive to the need for accurate assessment of the performance and success of groundwater recovery systems for contaminant plume abatement and aquifer restoration. Several assessment methods are available to measure the long-term performance of a groundwater recovery system. This paper presents six assessment techniques: degree of compliance with regulatory agency agreement (Consent Order of Record of Decision), hydraulic demonstration of system performance, contaminant mass recovery calculation, system design and performance comparison, statistical evaluation of groundwater quality and preferably, integration of the assessment methods. Applying specific recovery system assessment methods depends upon the type, amount, and quality of data available. Use of an integrated approach is encouraged to evaluate the success of a groundwater recovery and treatment system. The methods presented in this paper are for engineers and corporate management to use when discussing the effectiveness of groundwater remediation systems with their environmental consultant. In addition, an independent (third party) system evaluation is recommended to be sure that a recovery system operates efficiently and with minimum expense.

  20. Long-term groundwater depletion in the United States.

    PubMed

    Konikow, Leonard F

    2015-01-01

    The volume of groundwater stored in the subsurface in the United States decreased by almost 1000 km3 during 1900-2008. The aquifer systems with the three largest volumes of storage depletion include the High Plains aquifer, the Mississippi Embayment section of the Gulf Coastal Plain aquifer system, and the Central Valley of California. Depletion rates accelerated during 1945-1960, averaging 13.6 km3/year during the last half of the century, and after 2000 increased again to about 24 km3/year. Depletion intensity is a new parameter, introduced here, to provide a more consistent basis for comparing storage depletion problems among various aquifers by factoring in time and areal extent of the aquifer. During 2001-2008, the Central Valley of California had the largest depletion intensity. Groundwater depletion in the United States can explain 1.4% of observed sea-level rise during the 108-year study period and 2.1% during 2001-2008. Groundwater depletion must be confronted on local and regional scales to help reduce demand (primarily in irrigated agriculture) and/or increase supply. PMID:25510437

  1. PROVEN ALTERNATIVES FOR ABOVEGROUND TREATMENT OF ARSENIC IN GROUNDWATER

    EPA Science Inventory

    This report was prepared as an issue paper for the EPA Engineering Forum, summarizes experiences with proven aboveground treatment alternatives for arsenic in groundwater, and provides information on their relative performance and cost. The four technologies reviewed are: preci...

  2. Treatment of Uncertainty in Groundwater Modeling: A (Limited) Research Perspective

    SciTech Connect

    Meyer, Philip D.; Cohen, Stephen J.

    2010-05-16

    Groundwater systems are complex, exhibiting significant heterogeneity across multiple scales, multiple interacting processes, and nonlinear behaviors. Groundwater systems are also open, often with poorly defined boundaries and time-dependent, uncertain boundary forcings (e.g., recharge). As a consequence, a groundwater model cannot be expected to precisely reflect the system it represents and the model results are uncertain quantities. The dominant language of uncertainty is probability and the majority of research in the treatment of uncertainty in groundwater modeling has been directed at developing and improving probabilistic methods for these models. One area of recent research has been methods for assessing the impact of model uncertainty in groundwater analyses. This line of research is part of a long-term trend of increasing appreciation for the importance of providing estimates of uncertainty in groundwater model outputs. The research was motivated by observations of nonuniqueness in model parameterizations, the sensitivity of groundwater model output to model structural choices, and a history of practice that established the importance of iterative improvement in the conceptual basis of groundwater models. Among the methods proposed for assessing model uncertainty, we discuss Bayesian model averaging, it’s theoretical basis and research development. We outline critical arguments and discuss alternative approaches. Finally, we briefly describe a regulatory application of groundwater modeling that used Bayesian model averaging concepts to resolve a key conceptual model uncertainty.

  3. Preliminary remedial action objectives for the Tank 16 groundwater operable unit

    SciTech Connect

    Miles, W.C. Jr.

    1992-10-28

    Tank 16 is a High Level Radioactive Waste tank in the H-Area Tank Farm on the Savannah River Site that was placed into service in May 1959. A leak was detected in one of the construction weld joints while the tank was being filled. Before jet evacuation of the tank waste was completed, the leak overflowed the annulus pan and an estimated 16 to 700 gallons of waste escaped to the environment (soil and groundwater) over a six hour period contaminating approximately 1,600--70,000 cubic feet of soil with up to 5000 curies of activity (principally Cs{sup 137}). The Tank 16 bottom is constructed below the groundwater table which resulted in almost immediate contamination of that medium. Low groundwater flow rates, the ion exchange property of adjacent soils, and the distance to the nearest surface water bodies (1,500 to 8,000 feet) indicates that surface water and sediment outcrop of contaminates may be expected between 44 and 530 years (Poe et al., 1974). Remedial action objectives consist of medium-specific and operable unit specific goals for protecting human health and the environment. These objectives are specific and do not limit the range of alternatives that may be developed.A range of remedial technologies, which provides for treatment, containment, and removal requirements of contaminated media remaining at the Tank 16 groundwater operable unit, is identified and developed for each general response action.

  4. Preliminary remedial action objectives for the Tank 16 groundwater operable unit

    SciTech Connect

    Miles, W.C. Jr.

    1992-10-28

    Tank 16 is a High Level Radioactive Waste tank in the H-Area Tank Farm on the Savannah River Site that was placed into service in May 1959. A leak was detected in one of the construction weld joints while the tank was being filled. Before jet evacuation of the tank waste was completed, the leak overflowed the annulus pan and an estimated 16 to 700 gallons of waste escaped to the environment (soil and groundwater) over a six hour period contaminating approximately 1,600--70,000 cubic feet of soil with up to 5000 curies of activity (principally Cs[sup 137]). The Tank 16 bottom is constructed below the groundwater table which resulted in almost immediate contamination of that medium. Low groundwater flow rates, the ion exchange property of adjacent soils, and the distance to the nearest surface water bodies (1,500 to 8,000 feet) indicates that surface water and sediment outcrop of contaminates may be expected between 44 and 530 years (Poe et al., 1974). Remedial action objectives consist of medium-specific and operable unit specific goals for protecting human health and the environment. These objectives are specific and do not limit the range of alternatives that may be developed.A range of remedial technologies, which provides for treatment, containment, and removal requirements of contaminated media remaining at the Tank 16 groundwater operable unit, is identified and developed for each general response action.

  5. Remedial Investigation/Feasibility Study Work Plan for the 200-UP-1 Groundwater Operable Unit, Hanford Site, Richland, Washington. Revision

    SciTech Connect

    Not Available

    1994-01-01

    This work plan identifies the objectives, tasks, and schedule for conducting a Remedial Investigation/Feasibility Study for the 200-UP-1 Groundwater Operable Unit in the southern portion of the 200 West Groundwater Aggregate Area of the Hanford Site. The 200-UP-1 Groundwater Operable Unit addresses contamination identified in the aquifer soils and groundwater within its boundary, as determined in the 200 West Groundwater Aggregate Area Management Study Report (AAMSR) (DOE/RL 1992b). The objectives of this work plan are to develop a program to investigate groundwater contaminants in the southern portion of the 200 West Groundwater Aggregate Area that were designated for Limited Field Investigations (LFIs) and to implement Interim Remedial Measures (IRMs) recommended in the 200 West Groundwater AAMSR. The purpose of an LFI is to evaluate high priority groundwater contaminants where existing data are insufficient to determine whether an IRM is warranted and collect sufficient data to justify and implement an IRM, if needed. A Qualitative Risk Assessment (QRA) will be performed as part of the LFI. The purpose of an IRM is to develop and implement activities, such as contaminant source removal and groundwater treatment, that will ameliorate some of the more severe potential risks of groundwater contaminants prior to the RI and baseline Risk Assessment (RA) to be conducted under the Final Remedy Selection (FRS) at a later date. This work plan addresses needs of a Treatability Study to support the design and implementation of an interim remedial action for the Uranium-{sup 99}{Tc}-Nitrate multi-contaminant IRM plume identified beneath U Plant.

  6. In situ treatment of mixed contaminants in groundwater: Application of zero-valence iron and palladized iron for treatment of groundwater contaminated with trichloroethene and technetium-99

    SciTech Connect

    Korte, N.E.; Muck, M.T.; Zutman, J.L.; Schlosser, R.M.; Liang, L.; Gu, B.; Siegrist, R.L. |; Houk, T.C.; Fernando, Q.

    1997-04-01

    The overall goal of this portion of the project was to package one or more unit processes, as modular components in vertical and/or horizontal recirculation wells, for treatment of volatile organic compounds (VOCs) [e.g., trichloroethene (TCE)] and radionuclides [e.g., technetium (Tc){sup 99}] in groundwater. The project was conceived, in part, because the coexistence of chlorinated hydrocarbons and radionuclides has been identified as the predominant combination of groundwater contamination in the US Department of Energy (DOE) complex. Thus, a major component of the project was the development of modules that provide simultaneous treatment of hydrocarbons and radionuclides. The project objectives included: (1) evaluation of horizontal wells for inducing groundwater recirculation, (2) development of below-ground treatment modules for simultaneous removal of VOCs and radionuclides, and (3) demonstration of a coupled system (treatment module with recirculation well) at a DOE field site where both VOCs and radionuclides are present in the groundwater. This report is limited to the innovative treatment aspects of the program. A report on pilot testing of the horizontal recirculation system was the first report of the series (Muck et al. 1996). A comprehensive report that focuses on the engineering, cost and hydrodynamic aspects of the project has also been prepared (Korte et al. 1997a).

  7. Simplified Method for Groundwater Treatment Using Dilution and Ceramic Filter

    NASA Astrophysics Data System (ADS)

    Musa, S.; Ariff, N. A.; Kadir, M. N. Abdul; Denan, F.

    2016-07-01

    Groundwater is one of the natural resources that is not susceptible to pollutants. However, increasing activities of municipal, industrial, agricultural or extreme land use activities have resulted in groundwater contamination as occured at the Research Centre for Soft Soil Malaysia (RECESS), Universiti Tun Hussein Onn Malaysia (UTHM). Thus, aims of this study is to treat groundwater by using rainwater and simple ceramic filter as a treatment agent. The treatment uses rain water dilution, ceramic filters and combined method of dilute and filtering as an alternate treatment which are simple and more practical compared to modern or chemical methods. The water went through dilution treatment processes able to get rid of 57% reduction compared to initial condition. Meanwhile, the water that passes through the filtering process successfully get rid of as much as 86% groundwater parameters where only chloride does not pass the standard. Favorable results for the combination methods of dilution and filtration methods that can succesfully eliminate 100% parameters that donot pass the standards of the Ministry of Health and the Interim National Drinking Water Quality Standard such as those found in groundwater in RECESS, UTHM especially sulfate and chloride. As a result, it allows the raw water that will use clean drinking water and safe. It also proves that the method used in this study is very effective in improving the quality of groundwater.

  8. Identification of manganese as a toxicant in a groundwater treatment system: Addressing naturally occurring toxicants

    SciTech Connect

    Goodfellow, W. Jr.; Sohn, V.; Richey, M.; Yost, J.

    1995-12-31

    Effluent from a groundwater remediation system at a bulk oil storage and distribution terminal has been chronically toxic to Ceriodaphnia dubia. The remediation system was designed in response to a hydrocarbon plume in the area of the terminal. The remediation system consists of a series of groundwater recovery wells and groundwater intercept trench systems with groundwater treatment and phased-separated hydrocarbon recovery systems. The groundwater treatment and petroleum recovery systems consist of oil/water separators, product recovery tanks, air strippers, filters, and carbon adsorption units. The characteristics of this effluent are low total suspended solids, total dissolved solids, and hardness concentrations as well as meeting stringent NPDES permit requirements for lead, copper, zinc, mercury, total petroleum hydrocarbons, and BTEX. Additional priority pollutant evaluations revealed no compounds of concern. Performance of a Toxicity identification Evaluation (TIE) indicated that manganese was the principle toxicant in the effluent. Manganese is a naturally occurring constituent in this groundwater source and is not added to the treatment system. This paper will present the results of the TIE with a discussion of treatability/control options for manganese control at this facility. Recommendations for addressing naturally occurring toxicants that are not a result of the facility`s operations will also be presented.

  9. Evaluation of advanced oxidation process for the treatment of groundwater

    SciTech Connect

    Garland, S.B. II ); Peyton, G.R. ); Rice, L.E. . Kansas City Div.)

    1990-01-01

    An advanced oxidation process utilizing ozone, ultraviolet radiation, and hydrogen peroxide was selected for the removal of chlorinated hydrocarbons, particularly trichlorethene and 1,2-dichlorethene, from groundwater underlying the US Department of Energy Kansas City Plant. Since the performance of this process for the removal of organics from groundwater is not well-documented, an evaluation was initiated to determine the performance of the treatment plant, document the operation and maintenance costs experience, and evaluate contaminant removal mechanisms. 11 refs., 3 figs.

  10. Chlorine-36 in groundwater of the United States: empirical data

    NASA Astrophysics Data System (ADS)

    Davis, Stanley; Moysey, Stephen; Cecil, DeWayne; Zreda, Marek

    2002-11-01

    Natural production of the radionuclide chlorine-36 (36Cl) has provided a valuable tracer for groundwater studies. The nuclear industry, especially the testing of thermonuclear weapons, has also produced large amounts of 36Cl that can be detected in many samples of groundwater. In order to be most useful in hydrologic studies, the natural production prior to 1952 should be distinguished from more recent artificial sources. The object of this study was to reconstruct the probable preanthropogenic levels of 36Cl in groundwater in the United States. Although significant local variations exist, they are superimposed on a broad regional pattern of 36Cl/Cl ratios in the United States. Owing to the influence of atmospherically transported ocean salt, natural ratios of 36Cl/total Cl are lowest near the coast and increase to a maximum in the central Rocky Mountains of the United States. Résumé. La production naturelle du radionucléide chlore-36 (36Cl) fournit un intéressant traceur pour l'étude des eaux souterraines. L'industrie nucléaire, en particulier les essais de bombes thermonucléaires, a également produit de grandes quantités de 36Cl qui a pu être détecté dans de nombreux échantillons d'eau souterraine. Afin d'en améliorer l'usage dans les études hydrologiques, la production naturelle avant 1952 doit être distinguée des sources artificielles plus récentes. L'objectif de cette étude a été la reconstruction des niveaux probables de 36Cl dans les eaux souterraines des États-Unis, avant la production anthropique du 36Cl. Bien qu'il existe des variations locales significatives, elles se surimposent à un canevas régional de rapports 36Cl/Cl dans les États-Unis. Du fait de l'influence du sel océanique transporté dans l'atmosphère, les rapports naturels de 36Cl/Cl total sont plus faibles près de la côte et augmentent jusqu'à un maximum dans les Montagnes Rocheuses centrales des États-Unis. Resumen. La producción natural del radionucleido cloro

  11. Groundwater.

    ERIC Educational Resources Information Center

    Braids, Olin C.; Gillies, Nola P.

    1978-01-01

    Presents a literature review of groundwater quality covering publications of 1977. This review includes: (1) sources of groundwater contamination; and (2) management of groundwater. A list of 59 references is also presented. (HM)

  12. Biological groundwater treatment for chromium removal at low hexavalent chromium concentrations.

    PubMed

    Mamais, Daniel; Noutsopoulos, Constantinos; Kavallari, Ioanna; Nyktari, Eleni; Kaldis, Apostolos; Panousi, Eleni; Nikitopoulos, George; Antoniou, Kornilia; Nasioka, Maria

    2016-06-01

    The objective of this work is to develop and evaluate biological groundwater treatment systems that will achieve hexavalent chromium reduction and total chromium removal from groundwater at hexavalent chromium (Cr(VI)) groundwater concentrations in the 0-200 μg/L range. Three lab-scale units operated, as sequencing batch reactors (SBR) under aerobic, anaerobic and anaerobic-aerobic conditions. All systems received groundwater with a Cr(VI) content of 200 μg/L. In order to support biological growth, groundwater was supplemented with milk, liquid cheese whey or a mixture of sugar and milk to achieve a COD concentration of 200 mg/L. The results demonstrate that a fully anaerobic system or an anaerobic-aerobic system dosed with simple or complex external organic carbon sources can lead to practically complete Cr(VI) reduction to Cr(III). The temperature dependency of maximum Cr(VI) removal rates can be described by the Arrhenius relationship. Total chromium removal in the biological treatment systems was not complete because a significant portion of Cr(III) remained in solution. An integrated system comprising of an anaerobic SBR followed by a sand filter achieved more than 95% total chromium removal thus resulting in average effluent total and dissolved chromium concentrations of 7 μg/L and 3 μg/L, respectively. PMID:26971177

  13. Technology Evaluation Report: Biological Treatment of Wood Preserving Site Groundwater by Biotrol, Inc

    EPA Science Inventory

    Biological Treatment of Wood Preserving SITE Groundwater by Biotrol, Inc. BioTrol's pilot-scale, fixed-film biological treatment system was evaluated for its effectiveness at removing pentachlorophenol from groundwater. The system employs indigenous microorganisms amended wit...

  14. Ground-Water Availability in the United States

    USGS Publications Warehouse

    Reilly, Thomas E.; Dennehy, Kevin F.; Alley, William M.; Cunningham, William L.

    2008-01-01

    Ground water is among the Nation's most important natural resources. It provides half our drinking water and is essential to the vitality of agriculture and industry, as well as to the health of rivers, wetlands, and estuaries throughout the country. Large-scale development of ground-water resources with accompanying declines in ground-water levels and other effects of pumping has led to concerns about the future availability of ground water to meet domestic, agricultural, industrial, and environmental needs. The challenges in determining ground-water availability are many. This report examines what is known about the Nation's ground-water availability and outlines a program of study by the U.S. Geological Survey Ground-Water Resources Program to improve our understanding of ground-water availability in major aquifers across the Nation. The approach is designed to provide useful regional information for State and local agencies who manage ground-water resources, while providing the building blocks for a national assessment. The report is written for a wide audience interested or involved in the management, protection, and sustainable use of the Nation's water resources.

  15. Effects of Climate Variability and Change on Groundwater Resources of the United States

    USGS Publications Warehouse

    Gurdak, Jason S.; Hanson, Randall T.; Green, Timothy R.

    2009-01-01

    Groundwater is an important part of the global fresh water supply and is affected by climate. U.S. Geological Survey (USGS) scientists are working with local, State, Federal, and international partners to understand how the availability and sustainability of groundwater resources in the United States will be affected by climate variability and change. This fact sheet describes climate variability and change, important groundwater resources of the Nation, and how USGS research is helping to answer critical questions about the effects of climate on groundwater.

  16. Pilot-scale treatability test plan for the 200-UP-1 groundwater Operable Unit

    SciTech Connect

    Wittreich, C.D.

    1994-05-01

    This document presents the treatability test plan for pilot-scale pump and treat testing at the 200-UP-1 Operable Unit. This treatability test plan has been prepared in response to an agreement between the US Department of Energy, the US Environmental Protection Agency, and the Washington State Department of Ecology, as documented in Hanford Federal Facility Agreement and Consent Order (Ecology et al. 1989a) Change Control Form M-13-93-03 (Ecology et al. 1994). The agreement also requires that, following completion of the activities described in this test plan, a 200-UP-1 Operable Unit interim remedial measure (IRM) proposed plan be developed for use in preparing an interim action record of decision (ROD). The IRM Proposed Plan will be supported by the results of the testing described in this treatability test plan, as well as by other 200-UP-1 Operable Unit activities (e.g., limited field investigation, development of a qualitative risk assessment). Once issued, the interim action ROD will specify the interim action for groundwater contamination at the 200-UP-1 Operable Unit. The approach discussed in this treatability test plan is to conduct a pilot-scale pump and treat test for the contaminant plume associated with the 200-UP-1 Operable Unit. Primary contaminants of concern are uranium and technetium-99; the secondary contaminant of concern is nitrate. The pilot-scale treatability testing presented in this test plan has as its primary purpose to assess the performance of aboveground treatment systems with respect to the ability to remove the primary contaminants in groundwater withdrawn from the contaminant plume.

  17. Passive treatment of wastewater and contaminated groundwater

    DOEpatents

    Phifer, Mark A.; Sappington, Frank C.; Millings, Margaret R.; Turick, Charles E.; McKinsey, Pamela C.

    2006-12-12

    A bioremediation system using inorganic oxide-reducing microbial consortia for the treatment of, inter alia coal mine and coal yard runoff uses a containment vessel for contaminated water and a second, floating phase for nutrients. Biodegradable oils are preferred nutrients.

  18. Passive treatment of wastewater and contaminated groundwater

    DOEpatents

    Phifer, Mark A.; Sappington, Frank C.; Millings, Margaret R.; Turick, Charles E.; McKinsey, Pamela C.

    2007-11-06

    A bioremediation system using inorganic oxide-reducing microbial consortia for the treatment of, inter alia coal mine and coal yard runoff uses a containment vessel for contaminated water and a second, floating phase for nutrients. Biodegradable oils are preferred nutrients.

  19. Groundwater Monitoring Plan for the Reactor Technology Complex Operable Unit 2-13

    SciTech Connect

    Richard P. Wells

    2007-03-23

    This Groundwater Monitoring Plan describes the objectives, activities, and assessments that will be performed to support the on-going groundwater monitoring requirements at the Reactor Technology Complex, formerly the Test Reactor Area (TRA). The requirements for groundwater monitoring were stipulated in the Final Record of Decision for Test Reactor Area, Operable Unit 2-13, signed in December 1997. The monitoring requirements were modified by the First Five-Year Review Report for the Test Reactor Area, Operable Unit 2-13, at the Idaho National Engineering and Environmental Laboratory to focus on those contaminants of concern that warrant continued surveillance, including chromium, tritium, strontium-90, and cobalt-60. Based upon recommendations provided in the Annual Groundwater Monitoring Status Report for 2006, the groundwater monitoring frequency was reduced to annually from twice a year.

  20. Groundwater protection policies and practices in the United Kingdom.

    PubMed

    Chave, P A

    2000-01-01

    This paper summarises the main objectives for groundwater protection and describes the system adopted in the UK. Groundwater is essential as a source of drinking-water, even in countries with high rainfall; it is used for irrigation and industrial purposes; and it often comprises the base flow of rivers under dry conditions. Water quality is threatened by industry, landfill leachate, agricultural contamination and mine drainage. Quantity is threatened by over-abstraction. The UK uses a risk-based concept of vulnerability to pollution and over-abstraction. A groundwater protection policy has been devised providing guidance on those activities which require control in groundwater protection zones, reflecting the vulnerability of the aquifer. The zones make use of the travel time of contaminants to the water abstraction point. All major activities such as water abstraction, waste disposal, and spreading of agricultural materials may thus be assessed in terms of their risk to the groundwater, and suitable precautions may be taken. Groundwater, once polluted, is an asset which is difficult and expensive to replace. Vulnerability assessment is a useful tool to assist in its protection. PMID:10842809

  1. Ground-water levels spring 1985, and ground-water level changes spring 1983 to spring 1985, in three basalt units underlying the Columbia Plateau, Washington and Oregon

    USGS Publications Warehouse

    Lane, R.C.; Whiteman, K.J.

    1989-01-01

    Groundwater level contour maps for three basalt units of the Columbia Plateau regional aquifer system were constructed by using water levels measured in 1,105 wells during 1985. These measurements then were compared with similar measurements from spring 1983 to assess the changes in groundwater levels over the 2-year period for each of the basalt units. Configuration of the groundwater contours and water level changes reflect (1) recharge and discharge; (2) hydraulic conductivity; (3) use of imported surface water for irrigation; and (4) pumpage of groundwater. The movement of groundwater within each basalt unit is controlled mainly by the major rivers, streams, and coulees, whereas variations in flow directions between units are related to the occurrence, extent, and hydraulic conductivity of the basalt units and sedimentary interbeds and to differences in the amounts of recharge to each unit. (USGS)

  2. The evolution of groundwater rights and groundwater management in New Mexico and the western United States

    NASA Astrophysics Data System (ADS)

    DuMars, Charles T.; Minier, Jeffrie D.

    Historically, rights in water originated as public property and only later became individualized rights to utilize the public resource, in a manner consistent with the public welfare needs of society, but protected by principles of property law. Five basic regulatory systems for rights in groundwater in the United States have evolved to date. The problems raised by the hydrologic differences between groundwater hydraulically connected to stream systems and groundwater in non-replenished aquifers have been resolved to some extent by a couple of leading court cases. Numerical modeling and other technical methodologies have also evolved to evaluate the scientific issues raised by the different hydrologic conditions, but these are not immune from criticism. The current role of aquifers is evolving into that of storage facilities for recycled water, and their utilization in this manner may be expanded even further in the future. The policy implications of the choices relating to joint management of ground and surface water cannot be overstated. As this paper demonstrates, proactive administration of future groundwater depletions that affect stream systems is essential to the ultimate ability to plan for exploitation, management and utilization of water resources in a rational way that coordinates present and future demand with the reality of scarcity of supply. The examples utilized in this paper demonstrate the need for capacity building, not just to develop good measurement techniques, or to train talented lawyers and judges to write good laws, but also for practical professional water managers to keep the process on a rational course, avoiding limitless exploitation of the resource as well as conservative protectionism that forever precludes its use. Historiquement, les droits d'eau étaient à l'origine un bien public; ils sont devenus plus tard des droits individualisés pour utiliser la ressource publique conformément aux besoins de salut public de la soci

  3. Ground-Water Recharge in Humid Areas of the United States--A Summary of Ground-Water Resources Program Studies, 2003-2006

    USGS Publications Warehouse

    Delin, Geoffrey N.; Risser, Dennis W.

    2007-01-01

    Increased demands on water resources by a growing population and recent droughts have raised awareness about the adequacy of ground-water resources in humid areas of the United States. The spatial and temporal variability of ground-water recharge are key factors that need to be quantified to determine the sustainability of ground-water resources. Ground-water recharge is defined herein as the entry into the saturated zone of water made available at the water-table surface, together with the associated flow away from the water table within the saturated zone (Freeze and Cherry, 1979). In response to the need for better estimates of ground-water recharge, the Ground-Water Resources Program (GWRP) of the U.S. Geological Survey (USGS) began an initiative in 2003 to estimate ground-water recharge rates in the relatively humid areas of the United States.

  4. The evolution of groundwater rights and groundwater management in New Mexico and the western United States

    NASA Astrophysics Data System (ADS)

    DuMars, Charles T.; Minier, Jeffrie D.

    Historically, rights in water originated as public property and only later became individualized rights to utilize the public resource, in a manner consistent with the public welfare needs of society, but protected by principles of property law. Five basic regulatory systems for rights in groundwater in the United States have evolved to date. The problems raised by the hydrologic differences between groundwater hydraulically connected to stream systems and groundwater in non-replenished aquifers have been resolved to some extent by a couple of leading court cases. Numerical modeling and other technical methodologies have also evolved to evaluate the scientific issues raised by the different hydrologic conditions, but these are not immune from criticism. The current role of aquifers is evolving into that of storage facilities for recycled water, and their utilization in this manner may be expanded even further in the future. The policy implications of the choices relating to joint management of ground and surface water cannot be overstated. As this paper demonstrates, proactive administration of future groundwater depletions that affect stream systems is essential to the ultimate ability to plan for exploitation, management and utilization of water resources in a rational way that coordinates present and future demand with the reality of scarcity of supply. The examples utilized in this paper demonstrate the need for capacity building, not just to develop good measurement techniques, or to train talented lawyers and judges to write good laws, but also for practical professional water managers to keep the process on a rational course, avoiding limitless exploitation of the resource as well as conservative protectionism that forever precludes its use. Historiquement, les droits d'eau étaient à l'origine un bien public; ils sont devenus plus tard des droits individualisés pour utiliser la ressource publique conformément aux besoins de salut public de la soci

  5. Methods and Indicators for Assessment of Regional Ground-Water Conditions in the Southwestern United States

    USGS Publications Warehouse

    Tillman, Fred D; Leake, Stanley A.; Flynn, Marilyn E.; Cordova, Jeffrey T.; Schonauer, Kurt T.; Dickinson, Jesse E.

    2008-01-01

    Monitoring the status and trends in the availability of the Nation's ground-water supplies is important to scientists, planners, water managers, and the general public. This is especially true in the semiarid to arid southwestern United States where rapid population growth and limited surface-water resources have led to increased use of ground-water supplies and water-level declines of several hundred feet in many aquifers. Individual well observations may only represent aquifer conditions in a limited area, and wells may be screened over single or multiple aquifers, further complicating single-well interpretations. Additionally, changes in ground-water conditions may involve time scales ranging from days to many decades, depending on the timing of recharge, soil and aquifer properties, and depth to the water table. The lack of an easily identifiable ground-water property indicative of current conditions, combined with differing time scales of water-level changes, makes the presentation of ground-water conditions a difficult task, particularly on a regional basis. One approach is to spatially present several indicators of ground-water conditions that address different time scales and attributes of the aquifer systems. This report describes several methods and indicators for presenting differing aspects of ground-water conditions using water-level observations in existing data-sets. The indicators of ground-water conditions developed in this study include areas experiencing water-level decline and water-level rise, recent trends in ground-water levels, and current depth to ground water. The computer programs written to create these indicators of ground-water conditions and display them in an interactive geographic information systems (GIS) format are explained and results illustrated through analyses of ground-water conditions for selected alluvial basins in the Lower Colorado River Basin in Arizona.

  6. Fracturesis Jointitis: Causes, Symptoms, and Treatment in Groundwater Communities.

    PubMed

    Manda, Alex K; Horsman, Eric

    2015-01-01

    Fracturesis Jointitis is a grammatical disorder characterized by failure or inability to understand the difference between overarching and specific terms of brittle deformation features. The disorder leads to the use of the word "fracture" as a specific type of discontinuity rather than as an overarching term for mechanical breaks in rocks. This condition appears to be prevalent among groundwater practitioners working with fractured rocks. Common signs and symptoms of Fracturesis Jointitis include the use of terms such as "joints and fractures" and "joints, faults and fractures" when describing fractures in rocks. At best, such terms imply that a "fracture" is one of many kinds of features like joints and faults, and at worst that joints and faults are not fractures but something else. Using proper terms to identify specific fracture types is critical because fractures may act as either barriers to groundwater flow (e.g., faults or deformation bands) or conduits for flow (e.g., faults and joints), The treatment for Fracturesis Jointitis involves an education campaign highlighting to the groundwater community the different fracture types that exist, the modes by which fractures propagate and the role that these fractures play in facilitating or hindering groundwater flow. Those afflicted by Fracturesis Jointitis can be cured of the condition by avoiding the word "fractures" in phrases such as "joints and fractures" or by adding descriptive words before the word "fractures" to specify fracture types (e.g., "foliation-parallel" fractures). Only with a concerted education campaign can we rid our community of Fracturesis Jointitis. PMID:25393325

  7. Peroxone groundwater treatment of explosive contaminants demonstration and evaluation. Master`s thesis

    SciTech Connect

    McCrea, M.V.

    1997-03-01

    The purpose of this thesis is to evaluate the performance and cost effectiveness of a Peroxone Groundwater Treatment Plant (PGTP) designed and operated by Montgomery Watson, in support of the Defense Evaluation Support Agency`s independent analysis for the United States Army Environmental Center (USAEC). Many Department of Defense installations have sites that contain groundwater contaminated with explosive materials. Primary methods for the removal of explosive materials involve the use of Granular Activated Carbon (GAC). This process, however, requires additional waste disposal and treatment of explosive laden GAC, thereby incurring additional costs. An alternate method for the treatment of contaminated groundwater involves the use of hydrogen peroxide (H2O2) in conjunction with ozone (03). This method is referred to as the Peroxone oxidation process. A demonstration of the PGTP was conducted from 19 August to 8 November, 1996, at Cornhusker Army Ammunition Plant (CAAP), Grand Island, Nebraska using a small scale version with a maximum flow rate of 25 gallons per minute. The explosive contaminants analyzed during the demonstration include 2,4,6-Trinitrotoluene (TNT), 1,3,5-Trinitrobenzene (TNB), 1,3,5-Triazine (RDX), and Total Nitrobodies. Peroxone cost effectiveness was evaluated using a 30 year life cycle cost comparison to GAC and Ultraviolet/Ozone processes.

  8. Design of automated oil sludge treatment unit

    NASA Astrophysics Data System (ADS)

    Chukhareva, N.; Korotchenko, T.; Yurkin, A.

    2015-11-01

    The article provides the feasibility study of contemporary oil sludge treatment methods. The basic parameters of a new resource-efficient oil sludge treatment unit that allows extracting as much oil as possible and disposing other components in efficient way have been outlined. Based on the calculation results, it has been revealed that in order to reduce the cost of the treatment unit and the expenses related to sludge disposal, it is essential to apply various combinations of the existing treatment methods.

  9. Modeling the Effects of Groundwater-fed Irrigation on Terrestrial Hydrology over the Conterminous United States

    SciTech Connect

    Leng, Guoyong; Huang, Maoyi; Tang, Qiuhong; Gao, Huilin; Leung, Lai-Yung R.

    2014-06-01

    Human alteration of the land surface hydrologic cycle is substantial. Recent studies suggest that local water management practices including groundwater pumping and irrigation could significantly alter the quantity and distribution of water in the terrestrial system, with potential impacts on weather and climate through land-atmosphere feedbacks. In this study, we incorporated a groundwater withdrawal scheme into the Community Land Model version 4 (CLM4). To simulate the impact of irrigation realistically, we calibrated the CLM4 simulated irrigation amount against observations from agriculture census at the county scale over the conterminous United States (CONUS). The water used for irrigation was then removed from the surface runoff and groundwater aquifer according to a ratio determined from the county-level agricultural census data. Based on the simulations, the impact of groundwater withdrawals for irrigation on land surface and subsurface fluxes were investigated. Our results suggest that the impacts of irrigation on latent heat flux and potential recharge when water is withdrawn from surface water alone or from both surface and groundwater are comparable and local to the irrigation areas. However, when water is withdrawn from groundwater for irrigation, greater effects on the subsurface water balance were found, leading to significant depletion of groundwater storage in regions with low recharge rate and high groundwater exploitation rate. Our results underscore the importance of local hydrologic feedbacks in governing hydrologic response to anthropogenic change in CLM4 and the need to more realistically simulate the two-way interactions among surface water, groundwater, and atmosphere to better understand the impacts of groundwater pumping on irrigation efficiency and climate.

  10. Pilot scale evaluation of peroxone for treatment of contaminated groundwater

    SciTech Connect

    Zappi, M.; Swindle, R.; Harvey, S.; Morgan, R.; Strang, D.; Smith, J.

    1994-12-31

    Advance oxidation processes (AOPS) are treatment processes that rely on the hydroxyl radical to destroy contaminants in polluted waters. Peroxone is an advanced oxidation process that utilizes the reaction of ozone and hydrogen peroxide to produce hydroxyl radicals without the requirement of ultraviolet light. The USAE Waterways Experiment Station (WES) evaluated the use of peroxone at Rocky Mountain Arsenal (RMA) for treatment of groundwater contaminated with diisopropylmethylphosphonate (DIMP) and low levels of pesticides. This evaluation was performed at RMA using a pilot scale treatment system. Results indicate that DIMP was easily oxidized to below detection limit levels. Optimization of the process indicated that a 250 mg/l hydrogen peroxide dose in four columns plumbed in series that were all sparged with 2.2% ozonated air at a rate of 2.S scfm.

  11. Groundwater Monitoring and Field Sampling Plan for Operable Unit 10-08

    SciTech Connect

    M. S. Roddy

    2007-05-01

    This plan describes the groundwater sampling and water level monitoring that will be conducted to evaluate contaminations in the Snake River Plain Aquifer entering and leaving the Idaho National Laboratory. The sampling and monitoring locations were selected to meet the data quality objectives detailed in this plan. Data for the Snake River Plain Aquifer obtained under this plan will be evaluated in the Operable Unit 10-08 Remedial Investigation/Feasibility Study report and will be used to support the Operable Unit 10-08 Sitewide groundwater model.

  12. Qualitative risk assessment for the 100-KR-4 groundwater operable unit

    SciTech Connect

    Biggerstaff, R.L.

    1994-06-30

    This report provides the qualitative risk assessment (QRA) for the 100-KR-4 groundwater operable unit at the US Department of Energy`s (DOE) Hanford Site in southeastern Washington State. The extent of the groundwater beneath the 100 K Area is defined in the Remedial Investigation/Feasibility Study Work Plan for the 100-KR-4 Operable Unit (DOE-RL 1992a). The QRA is an evaluation or risk using a limited amount of data and a predefined set of human and environmental exposure scenarios and is not intended to replace or be a substitute for a baseline risk assessment.

  13. Data validation summary report: 300-FF-5 operable unit; Round 6 groundwater

    SciTech Connect

    Hulstrom, L.C.

    1994-03-21

    Laboratory data for Sixth Round Groundwater samples collected during the 300-FF-5 Operable Unit Remedial Investigation have been reviewed and validated to ensure that they are of sufficient quality to support decisions regarding further actions to be taken at the 300-FF-5 Operable Unit. Table 1-1 is a summary of the validated samples. This report summarizes the results previously presented to Westinghouse Hanford in a series of Preliminary Quality Assurance Reports (PQAR) for the 300-FF-5 Sixth Round Groundwater samples. In some instances, the data qualifiers originally presented in the PQARs have been changed based upon further review of the data; these changes are highlighted in the text.

  14. Modelling of sequential groundwater treatment with zero valent iron and granular activated carbon.

    PubMed

    Bayer, Peter; Finkel, Michael

    2005-06-01

    Multiple contaminant mixtures in groundwater may not efficiently be treated by a single technology if contaminants possess rather different properties with respect to sorptivity, solubility, and degradation potential. An obvious choice is to use sequenced units of the generally accepted treatment materials zero valent iron (ZVI) and granular activated carbon (GAC). However, as the results of this modelling study suggest, the required dimensions of both reactor units may strongly differ from those expected on the grounds of a contaminant-specific design. This is revealed by performing an analysis for a broad spectrum of design alternatives through numerical experiments for selected patterns of contaminant mixtures consisting of monochlorobenzene, tetrachloroethylene, trichloroethylene (TCE), cis-1,2-dichloroethylene (cis-DCE), and vinyl chloride (VC). It is shown that efficient treatment can be achieved only if competitive sorption effects in the GAC unit as well as the formation of intermediate products in the ZVI unit are carefully taken into account. Cost-optimal designs turned out to vary extremely depending on the prevailing conditions concerning contaminant concentrations, branching ratios, and unit costs of both reactor materials. Where VC is the critical contaminant, due to high initial concentration or extensive production as an intermediate, two options are cost-effective: an oversized ZVI unit with an oversized GAC unit or a pure GAC reactor. PMID:15949610

  15. The X-625 Groundwater Treatment Facility: A field-scale test of trichloroethylene dechlorination using iron filings for the X-120/X-749 groundwater plume

    SciTech Connect

    Liang, L.; West, O.R.; Korte, N.E.

    1997-09-01

    The dehalogenation of chlorinated solvents by zero-valence iron has recently become the subject of intensive research and development as a potentially cost-effective, passive treatment for contaminated groundwater through reactive barriers. Because of its successful application in the laboratory and other field sites, the X-625 Groundwater Treatment Facility (GTF) was constructed to evaluate reactive barrier technology for remediating trichloroethylene (TCE)-contaminated groundwater at the Portsmouth Gaseous Diffusion Plant (PORTS). The X-625 GTF was built to fulfill the following technical objectives: (1) to test reactive barrier materials (e.g., iron filings) under realistic groundwater conditions for long term applications, (2) to obtain rates at which TCE degrades and to determine by-products for the reactive barrier materials tested, and (3) to clean up the TCE-contaminated water in the X-120 plume. The X-625 is providing important field-scale and long-term for the evaluation and design of reactive barriers at PORTS. The X-625 GTS is a unique facility not only because it is where site remediation is being performed, but it is also where research scientists and process engineers can test other promising reactive barrier materials. In addition, the data collected from X-625 GTF can be used to evaluate the technical and economic feasibility of replacing the activated carbon units in the pump-and-treat facilities at PORTS.

  16. 20th Century Groundwater in the Northeast United States: A case study quantifying the impact of groundwater policies in New Jersey

    NASA Astrophysics Data System (ADS)

    Kanwar, P. S.; Arrigo, J. S.; Thomas, B.; Vogel, R. M.; Hoover, J. H.

    2010-12-01

    Groundwater is a vital resource throughout the Northeast corridor and is an important water source for domestic, industrial and irrigation purposes. During the 20th century, suburban groundwater withdrawals intensified with increasing population growth, the advent of rural electrification and sophisticated pumping technologies, thus, the need for effective groundwater management becomes increasingly important in the region. Data from the Unites States Geological Survey National Water-Use Information Program documents this concentrated use of groundwater in suburban areas, and is particularly prominent across the majority of New Jersey. Focusing on New Jersey as an area of significant groundwater use and increasing demand, this project investigates total groundwater withdrawals in conjunction with a policy-based framework, facilitating an awareness of groundwater impacts as informed through existing policy during the 20th century. The objectives of this study are to identify the relevant federal, statewide and municipal policies that evolved in the state of New Jersey during the 20th century, and examine the groundwater withdrawal trends for the state of New Jersey between 1950 - 2005. Preliminary results revealed that increased restrictions on groundwater policy between 1982 and 1997 had an observable affect on reducing total groundwater withdrawals. Multivariate regression analyses using indicator variables, i.e. mixed effects model, will be used to explore relationships between county specific withdrawals and significant policy that may have influenced groundwater usage. It is anticipated to observe a strong correlation between groundwater withdrawals and the effectiveness of the implemented groundwater policies. Future collaborative work will further investigate the effectiveness of policy as hydrologically evidenced by alterations in baseflow contribution to streamflow, and groundwater persistence.

  17. Groundwater Monitoring at the 1100-EM-1 Operable Unit

    SciTech Connect

    Newcomer, Darrell R.

    2007-04-25

    The purpose of this report is to provide a comprehensive summary of the distribution and trends of volatile organic compound concentrations near USDOE’s Horn Rapids Landfill (HRL). This report focuses mainly on the TCE plume monitored in the top of the unconfined aquifer near the HRL, but also addresses potential breakdown products of TCE. TCE concentrations in deep portions of the unconfined aquifer and the underlying confined aquifer are discussed to show the vertical extent of contamination. This report incorporates TCE data from offsite wells at the AREVA facility south of the Hanford Site. Discussion of TCE in groundwater in the 300 Area is included to differentiate between contaminant plumes and their sources in the 300 Area and near the HRL. Chromium monitoring results from a specific well downgradient of the 1171 Building is also included.

  18. Arsenic Contaminated Groundwater and Its Treatment Options in Bangladesh

    PubMed Central

    Jiang, Jia-Qian; Ashekuzzaman, S. M.; Jiang, Anlun; Sharifuzzaman, S. M.; Chowdhury, Sayedur Rahman

    2012-01-01

    Arsenic (As) causes health concerns due to its significant toxicity and worldwide presence in drinking water and groundwater. The major sources of As pollution may be natural process such as dissolution of As-containing minerals and anthropogenic activities such as percolation of water from mines, etc. The maximum contaminant level for total As in potable water has been established as 10 µg/L. Among the countries facing As contamination problems, Bangladesh is the most affected. Up to 77 million people in Bangladesh have been exposed to toxic levels of arsenic from drinking water. Therefore, it has become an urgent need to provide As-free drinking water in rural households throughout Bangladesh. This paper provides a comprehensive overview on the recent data on arsenic contamination status, its sources and reasons of mobilization and the exposure pathways in Bangladesh. Very little literature has focused on the removal of As from groundwaters in developing countries and thus this paper aims to review the As removal technologies and be a useful resource for researchers or policy makers to help identify and investigate useful treatment options. While a number of technological developments in arsenic removal have taken place, we must consider variations in sources and quality characteristics of As polluted water and differences in the socio-economic and literacy conditions of people, and then aim at improving effectiveness in arsenic removal, reducing the cost of the system, making the technology user friendly, overcoming maintenance problems and resolving sludge management issues. PMID:23343979

  19. Arsenic contaminated groundwater and its treatment options in Bangladesh.

    PubMed

    Jiang, Jia-Qian; Ashekuzzaman, S M; Jiang, Anlun; Sharifuzzaman, S M; Chowdhury, Sayedur Rahman

    2013-01-01

    Arsenic (As) causes health concerns due to its significant toxicity and worldwide presence in drinking water and groundwater. The major sources of As pollution may be natural process such as dissolution of As-containing minerals and anthropogenic activities such as percolation of water from mines, etc. The maximum contaminant level for total As in potable water has been established as 10 µg/L. Among the countries facing As contamination problems, Bangladesh is the most affected. Up to 77 million people in Bangladesh have been exposed to toxic levels of arsenic from drinking water. Therefore, it has become an urgent need to provide As-free drinking water in rural households throughout Bangladesh. This paper provides a comprehensive overview on the recent data on arsenic contamination status, its sources and reasons of mobilization and the exposure pathways in Bangladesh. Very little literature has focused on the removal of As from groundwaters in developing countries and thus this paper aims to review the As removal technologies and be a useful resource for researchers or policy makers to help identify and investigate useful treatment options. While a number of technological developments in arsenic removal have taken place, we must consider variations in sources and quality characteristics of As polluted water and differences in the socio-economic and literacy conditions of people, and then aim at improving effectiveness in arsenic removal, reducing the cost of the system, making the technology user friendly, overcoming maintenance problems and resolving sludge management issues. PMID:23343979

  20. Groundwater dependent ecosystems and nutrient enrichment: a case study of the North Shropshire Meres, United Kingdom.

    NASA Astrophysics Data System (ADS)

    Gasca, David; Cousins, Mags; Duff, Robert

    2013-04-01

    The identification of groundwater dependent ecosystems within the landscape requires a detailed, site-specific understanding of the wetland water balance to assess the importance of all the hydrological processes effecting the hydrology and ecology of a wetland site. By determining transmission pathways for nutrients, wetland hydrology may also influence water quality status, especially in catchments where anthropogenic influences are significant. Groundwater contributions to wetlands remain one of the most difficult processes to measure or estimate. This is related to the heterogeneity of subsurface hydrogeological process and our ability to sample only a few locations within the wetland catchment. Given these limitations, we typically rely on theoretical assumptions or apply groundwater models to determine 'groundwater dependency'. This paper presents the results of a study of groundwater contributions and water quality in a series of meres (lakes) in north Shropshire, United Kingdom. The meres are relic landscape features of the last glaciation that are of high nature conservation importance, an importance that has declined in recent decades due to nutrient enrichment and changes in hydrological management. The paper reviews the landscape setting, hydrology, ecology and eutrophication history of the sites, and describes the development of a method for modelling groundwater contributions and the hydrology of the meres in general using a landscape-characterisation approach. Results have been used to identify the causes for ecological decline and to establish the most effective measures for the restoration of the wetland ecosystems as part of the EU Water Framework Directive.

  1. Seasonal forecasting of groundwater levels in principal aquifers of the United Kingdom

    NASA Astrophysics Data System (ADS)

    Mackay, J. D.; Jackson, C. R.; Brookshaw, A.; Scaife, A. A.; Cook, J.; Ward, R. S.

    2015-11-01

    To date, the majority of hydrological forecasting studies have focussed on using medium-range (3-15 days) weather forecasts to drive hydrological models and make predictions of future river flows. With recent developments in seasonal (1-3 months) weather forecast skill, such as those from the latest version of the UK Met Office global seasonal forecast system (GloSea5), there is now an opportunity to use similar methodologies to forecast groundwater levels in more slowly responding aquifers on seasonal timescales. This study uses seasonal rainfall forecasts and a lumped groundwater model to simulate groundwater levels at 21 locations in the United Kingdom up to three months into the future. The results indicate that the forecasts have skill; outperforming a persistence forecast and demonstrating reliability, resolution and discrimination. However, there is currently little to gain from using seasonal rainfall forecasts over using site climatology for this type of application. Furthermore, the forecasts are not able to capture extreme groundwater levels, primarily because of inadequacies in the driving rainfall forecasts. The findings also show that the origin of forecast skill, be it from the meteorological input, groundwater model or initial condition, is site specific and related to the groundwater response characteristics to rainfall and antecedent hydro-meteorological conditions.

  2. Interim action record of decision remedial alternative selection: TNX area groundwater operable unit

    SciTech Connect

    Palmer, E.R.

    1994-10-01

    This document presents the selected interim remedial action for the TNX Area Groundwater Operable Unit at the Savannah River Site (SRS), which was developed in accordance with CERCLA of 1980, as amended by the Superfund Amendments and Reauthorization Act (SARA) of 1986, and to the extent practicable, the National Oil and Hazardous Substances Pollution contingency Plan (NCP). This decision is based on the Administrative Record File for this specific CERCLA unit.

  3. Current Conditions Risk Assessment for the 300-FF-5 Groundwater Operable Unit

    SciTech Connect

    Miley, Terri B.; Bunn, Amoret L.; Napier, Bruce A.; Peterson, Robert E.; Becker, James M.

    2007-11-01

    This report updates a baseline risk assessment for the 300 Area prepared in 1994. The update includes consideration of changes in contaminants of interest and in the environment that have occurred during the period of interim remedial action, i.e., 1996 to the present, as well as the sub-regions, for which no initial risk assessments have been conducted. In 1996, a record of decision (ROD) stipulated interim remedial action for groundwater affected by releases from 300 Area sources, as follows: (a) continued monitoring of groundwater that is contaminated above health-based levels to ensure that concentrations continue to decrease, and (b) institutional controls to ensure that groundwater use is restricted to prevent unacceptable exposure to groundwater contamination. In 2000, the groundwater beneath the two outlying sub-regions was added to the operable unit. In 2001, the first 5-year review of the ROD found that the interim remedy and remedial action objectives were still appropriate, although the review called for additional characterization activities. This report includes a current conditions baseline ecological and human health risk assessment using maximum concentrations in the environmental media of the 300-FF-5 Operable Unit and downstream conditions at the City of Richland, Washington. The scope for this assessment includes only current measured environmental concentrations and current use scenarios. Future environmental concentrations and future land uses are not considered in this assessment.

  4. Groundwater availability in the United States: the value of quantitative regional assessments

    USGS Publications Warehouse

    Dennehy, Kevin F.; Reilly, Thomas E.; Cunningham, William L.

    2015-01-01

    The sustainability of water resources is under continued threat from the challenges associated with a growing population, competing demands, and a changing climate. Freshwater scarcity has become a fact in many areas. Much of the United States surface-water supplies are fully apportioned for use; thus, in some areas the only potential alternative freshwater source that can provide needed quantities is groundwater. Although frequently overlooked, groundwater serves as the principal reserve of freshwater in the US and represents much of the potential supply during periods of drought. Some nations have requirements to monitor and characterize the availability of groundwater such as the European Union’s Water Framework Directive (EPCEU 2000). In the US there is no such national requirement. Quantitative regional groundwater availability assessments, however, are essential to document the status and trends of groundwater availability for the US and make informed water-resource decisions possible now and in the future. Barthel (2014) highlighted that the value of regional groundwater assessments goes well beyond just quantifying the resource so that it can be better managed. The tools and techniques required to evaluate these unique regional systems advance the science of hydrogeology and provide enhanced methods that can benefit local-scale groundwater investigations. In addition, a significant, yet under-utilized benefit is the digital spatial and temporal data sets routinely generated as part of these studies. Even though there is no legal or regulatory requirement for regional groundwater assessments in the US, there is a logical basis for their implementation. The purpose of this essay is to articulate the rationale for and reaffirm the value of regional groundwater assessments primarily in the US; however, the arguments hold for all nations. The importance of the data sets and the methods and model development that occur as part of these assessments is stressed

  5. In-situ wastewater treatment and groundwater remediation at a sugar beet processing facility

    SciTech Connect

    Olson, J.L.; Fuller-Pratt, P.R.; Mielke, R.A.

    1996-06-01

    Groundwater monitoring data collected at the Western Sugar Company sugar beet processing plant, in Billings, Montana identified groundwater mounding and groundwater nitrogen concentration increases associated with lime slurry discharge to an on-site storage pile. The nitrogen impacts (primarily ammonia) likely originated through decomposition of organic matter in the slurry. Initially, Western Sugar considered constructing an expensive anaerobic and nitrification-denitrification wastewater treatment system. However, further investigation of the lime pile revealed that it was already serving as an efficient filter and anaerobic reactor. Comparisons of slurry application with other land application systems suggested that groundwater nitrogen impacts could be minimized through groundwater capture, re-application, and improved slurry management. The resultant system required little capitol and maintenance cost. The immediate effect was to substantially decrease the groundwater mound. Subsequent monitoring has demonstrated a gradual decline in nitrogen concentrations under the lime pile and a considerable concentration decrease downgradient of the groundwater recovery system.

  6. APPLICATIONS ANALYSIS REPORT: BIOLOGICAL TREATMENT OF WOOD PRESERVING SITE GROUNDWATER BY BIOTROL, INC.

    EPA Science Inventory

    This report is an evaluation of the Biotrol, Inc. Aqueous Treatment System (BATS), a fixed-film, aerobic biological treatment process for contaminated groundwaters and other wastewaters. t summarizes and analyzes the results of the Superfund Innovative Technology Evaluation (SITE...

  7. Groundwater Drought and Recovery: a Case Study from the United Kingdom

    NASA Astrophysics Data System (ADS)

    Peach, D.; McKenzie, A. A.; Bloomfield, J.

    2012-12-01

    An understanding of the processes leading to the onset, duration and end of hydrological droughts is necessary to help improve the management of stressed or scarce water resources during such periods. In particular, the role and use of groundwater during episodes of drought is crucially important, since groundwater can provide relatively resilient water supplies during early stages of drought but maybe highly susceptible to relatively persistent or sustained droughts. Nevertheless, groundwater is seldom considered in drought analyses, and compared with other types of hydrological drought there have been few studies to date. The few previous studies of groundwater droughts at catchment- and regional-scale have shown that catchment and aquifer characteristics exert a strong influence on the spatio-temporal development of groundwater droughts as water deficit propagates through the terrestrial water cycle. In this context, the relationships between hydrogeological heterogeneity, catchment engineering infrastructure (storage), and decisions related to water resource management during drought events all shape the evolution and consequences of groundwater droughts. Here we examine the evolution of a recent regionally significant two-year drought across the United Kingdom (UK) and use it to investigate these relationships. We identify the drivers, characterise the development and spatio-temporal extent of the groundwater drought. In particular, we focus on the unusually rapid end and recovery from drought during what would normally be a period of groundwater recession. The UK, and in particular southern England, relies extensively on groundwater for public water supply, agricultural and industrial use, as well as for sustaining river flows that are essential to ecosystem health. In normal years relatively consistent rainfall patterns prevail, recharging aquifers over winter when evapotranspiration is minimal. However, by March 2012 large parts of the southern UK had

  8. Arsenic in Ground-Water Resources of the United States

    USGS Publications Warehouse

    Welch, Alan H.; Watkins, Sharon A.; Helsel, Dennis R.; Focazio, Michael J.

    2000-01-01

    Arsenic is a naturally occurring element in rocks, soils, and the waters in contact with them. Recognized as a toxic element for centuries, arsenic today also is a human health concern because it can contribute to skin, bladder, and other cancers (National Research Council, 1999). Recently, the National Research Council (1999) recommended lowering the current maximum contaminant level (MCL) allowed for arsenic in drinking water of 50 ?g/L (micrograms per liter), citing risks for developing bladder and other cancers. The U.S. Environmental Protection Agency (USEPA) will propose a new, and likely lower, arsenic MCL during 2000 (U.S. Environmental Protection Agency, 2000). This fact sheet provides information on where and to what extent natural concentrations of arsenic in ground water exceed possible new standards. The U.S. Geological Survey (USGS) has collected and analyzed arsenic in potable (drinkable) water from 18,850 wells in 595 counties across the United States during the past two decades. These wells are used for irrigation, industrial purposes, and research, as well as for public and private water supply. Arsenic concentrations in samples from these wells are similar to those found in nearby public supplies (see Focazio and others, 1999). The large number of samples, broad geographic coverage, and consistency of methods produce a more accurate and detailed picture of arsenic concentrations than provided by any previous studies.

  9. TREATMENT OF HIGHLY CONTAMINATED GROUNDWATER: A SITE DEMONSTRATION PROJECT

    EPA Science Inventory

    From 9-11/1994, the USEPA conducted a field demonstration of the remediation of highly contaminated groundwater at the Mascolite Superfund site located in Millville, NJ. Besides high concentrations of the major contaminant, methyl methacrylate (MMA), the groundwater also containe...

  10. Ground-water data collected in the Missouri River Basin units in Kansas during 1954

    USGS Publications Warehouse

    Mason, B.J.; Loye, Linda

    1955-01-01

    Ground water studies in the Missouri River basin were begun by the United States Geological Survey during the fall of 1945 as a part of a program for the development of the resources of the basin by the United States Bureau of  Reclamation and other federal agencies. The studies of ground-water resources in the part of Kansas that lies within the Missouri River basin have been coordinated with the cooperative program of ground-water studies which were already being made in Kansas by the U.S Geological Survey, the Kansas State Geological Survey, the Division of Sanitation of the Kansas Board of Health and the Division of Water Resources of the Kansas State Board of Agriculture.  

  11. Interannual to Multidecadal Climate Variability and Groundwater Resources of the Western United States

    NASA Astrophysics Data System (ADS)

    Gurdak, J. J.; Kuss, A. M.

    2011-12-01

    Climate variability and change have important implications for groundwater recharge, discharge, contaminant transport, and resource sustainability. Reliable predictions of groundwater sustainability due to climate change will require improved understanding of the effects of global scale atmosphere-ocean climate oscillations on interannual to multidecadal timescales. Climate variability on these timescales partially controls precipitation, air temperature, drought, evapotranspiration, streamflow, recharge, and mobilization of subsurface-chemical reservoirs. Climate variability can augment or diminish human stresses on groundwater, and the responses in storage can be dramatic when different climate cycles lie coincident in a positive or negative phase of variability. Thus, understanding climate variability has particular relevance for management decisions during drought and for water resources close to the limits of sustainability. Major findings will be presented from a national scale study of climate variability on recharge rates and groundwater levels, and will highlight regional aquifers of the western United States, including the Basin and Range (700,000 km2), Central Valley (52,000 km2), High Plains (450,000 km2), and Mississippi Embayment (181,000 km2) aquifer systems. Using singular spectrum analysis, the groundwater pumping signal was removed and natural variations were identified in groundwater levels as partially coincident with the El Niño/Southern Oscillation (ENSO) (2-6 year cycle), North Atlantic Oscillation (3-6 year cycle), Pacific Decadal Oscillation (PDO) (10-25 year cycle), and Atlantic Multidecadal Oscillation (AMO) (50-80 year cycle). The PDO was the most significant contributor to recharge and groundwater level fluctuations in most aquifers. In the Central Valley and the Basin and Range, the PDO contributes to the greatest amount of variance (ranging from 13.6-83%) in all precipitation and groundwater level time series, with moderate to strong

  12. Finding Balance Between Biological Groundwater Treatment and Treated Injection Water

    SciTech Connect

    Carlson, Mark A.; Nielsen, Kellin R.; Byrnes, Mark E.; Simmons, Sally A.; Morse, John J.; Geiger, James B.; Watkins, Louis E.; McFee, Phillip M.; Martins, K.

    2015-01-14

    At the U.S. Department of Energy’s Hanford Site, CH2M HILL Plateau Remediation Company operates the 200 West Pump and Treat which was engineered to treat radiological and chemical contaminants in groundwater as a result of the site’s former plutonium production years. Fluidized bed bioreactors (FBRs) are used to remove nitrate, metals, and volatile organic compounds. Increasing nitrate concentrations in the treatment plant effluent and the presence of a slimy biomass (a typical microorganism response to stress) in the FBRs triggered an investigation of nutrient levels in the system. Little, if any, micronutrient feed was coming into the bioreactors. Additionally, carbon substrate (used to promote biological growth) was passing through to the injection wells, causing biological fouling of the wells and reduced specific injectivity. Adjustments to the micronutrient feed improved microorganism health, but the micronutrients were being overfed (particularly manganese) plugging the injection wells further. Injection well rehabilitation to restore specific injectivity required repeated treatments to remove the biological fouling and precipitated metal oxides. A combination of sulfamic and citric acids worked well to dissolve metal oxides and sodium hypochlorite effectively removed the biological growth. Intensive surging and development techniques successfully removed clogging material from the injection wells. Ultimately, the investigation and nutrient adjustments took months to restore proper balance to the microbial system and over a year to stabilize injection well capacities. Carefully tracking and managing the FBRs and well performance monitoring are critical to balancing the needs of the treatment system while reducing fouling mechanisms in the injection wells.

  13. Fiscal Year 2009 Annual Report for Operable Unit 3-14, Tank Farm Soil and INTEC Groundwater

    SciTech Connect

    Forsythe, Howard S.

    2010-04-10

    This annual report summarizes maintenance, monitoring, and inspection activities performed to implement the selected remedy for Waste Area Group 3, Operable Unit 3-14, Tank Farm soil and groundwater at the Idaho Nuclear Technology and Engineering Center located within the Idaho National Laboratory Site. Results from monitoring perched water and groundwater at the Idaho Nuclear Technology and Engineering Center are also presented.

  14. Data validation report for the 100-HR-3 Operable Unit, fifth round groundwater samples

    SciTech Connect

    Vukelich, S.E.

    1994-01-20

    The data from the chemical analysis of 68 samples from the 100-HR-3 Operable Unit Third Quarter 1993 Groundwater Sampling Investigation and their related quality assurance samples were reviewed and validated to verify that reported sample results were of sufficient quality to support decisions regarding remedial actions performed at the site. Sample analysis included inorganics and general chemical parameters. Fifty three samples were validated for radiochemical parameters.

  15. U. T. R. [Unit Treatment Rehabilitation] Program.

    ERIC Educational Resources Information Center

    Versteck, Mary M.

    In the mid-70's mental health programs in Florida underwent a major change with the implementation of a Unit Treatment Rehabilitation (UTR) model of patient care, which emphasizes the re-socialization of patients and a team approach to mental health care. In response to this change, an innovative program was developed through coordination between…

  16. ADVANCED OXIDATION TECHNOLOGIES FOR THE TREATMENT OF CONTAMINATED GROUNDWATER

    EPA Science Inventory

    This paper presents information on two pilot-field appliations of advanced oxidation technologies for contaminated groundwater with organis. The two UV/oxidation technologies were developed by Ultrox International of Santa Ana, California and Peroxidatrion Systems, Inc. of Tucso...

  17. Chemical Reductive Treatment of Groundwater Chromate and Chlorinated Ethenes: Tests at Two Field Sites

    EPA Science Inventory

    Both hexavalent chromium (Cr(VI)) and chlorinated ethenes such as tetrachloroethene (PCE) are common groundwater contaminants. A pump-and-treat approach to remedy them usually is not satisfactory with respect to effectiveness and cost. Effective treatment technologies generally...

  18. 2008 Groundwater Monitoring Report Project Shoal Area, Corrective Action Unit 447

    SciTech Connect

    2009-03-01

    This report presents the 2008 groundwater monitoring results collected by the U.S. Department of Energy (DOE) Office of Legacy Management (LM) at the Project Shoal Area (PSA) Subsurface Corrective Action Unit (CAU) 447 located in Churchill County, Nevada. Responsibility for the environmental site restoration of the PSA was transferred from the DOE Office of Environmental Management to LM on October 1, 2006. The environmental restoration process and corrective action strategy for CAU 447 are conducted in accordance with the Federal Facility Agreement and Consent Order (FFACO 1996, as amended February 2008) entered into by DOE, the U.S. Department of Defense, and the State of Nevada. The corrective action strategy for the site includes proof of concept monitoring in support of site closure. This report summarizes investigation activities associated with CAU 447 that were conducted at the site during 2008. This is the second groundwater monitoring report prepared by LM for the PSA

  19. 2010 Groundwater Monitoring Report Project Shoal Area, Corrective Action Unit 447

    SciTech Connect

    2011-02-01

    This report presents the 2010 groundwater monitoring results collected by the U.S. Department of Energy (DOE) Office of Legacy Management (LM) at the Project Shoal Area (PSA) Subsurface Corrective Action Unit (CAU) 447 in Churchill County, Nevada. Responsibility for the environmental site restoration of the PSA was transferred from the DOE Office of Environmental Management to LM on October 1, 2006. The environmental restoration process and corrective action strategy for CAU 447 are conducted in accordance with the Federal Facility Agreement and Consent Order (FFACO 1996, as amended March 2010) entered into by DOE, the U.S. Department of Defense, and the State of Nevada. The corrective action strategy for the site includes monitoring in support of site closure. This report summarizes the results from the groundwater monitoring program during fiscal year 2010.

  20. 2008 Groundwater Monitoring Report Central Nevada Test Area, Corrective Action Unit 443

    SciTech Connect

    2009-03-01

    This report presents the 2008 groundwater monitoring results collected by the U.S. Department of Energy (DOE) Office of Legacy Management (LM) for the Central Nevada Test Area (CNTA) Subsurface Corrective Action Unit (CAU) 443. Responsibility for the environmental site restoration of the CNTA was transferred from the DOE Office of Environmental Management (DOE-EM) to DOE-LM on October 1, 2006. The environmental restoration process and corrective action strategy for CAU 443 are conducted in accordance with the Federal Facility Agreement and Consent Order (FFACO 2005) entered into by DOE, the U.S. Department of Defense, and the State of Nevada. The corrective action strategy for the site includes proof-of-concept monitoring in support of site closure. This report summarizes investigation activities associated with CAU 443 that were conducted at the site during fiscal year 2008. This is the second groundwater monitoring report prepared by DOE-LM for the CNTA.

  1. Volatile organic compounds in untreated ambient groundwater of the United States, 1985-1995

    USGS Publications Warehouse

    Squillace, P.J.; Moran, M.J.; Lapham, W.W.; Price, C.V.; Clawges, R.M.; Zogorski, J.S.

    1999-01-01

    As part of the National Water-Quality Assessment Program of the U.S. Geological Survey, an assessment of 60 volatile organic compounds (VOCs) in untreated, ambient groundwater of the conterminous United States was conducted based on samples collected from 2948 wells between 1985 and 1995. The samples represent urban and rural areas and drinking-water and nondrinking-water wells. A reporting level of 0.2 μg/L was used with the exception of 1,2-dibromo-3-chloropropane, which had a reporting level of 1.0 μg/L. Because ambient groundwater was targeted, areas of known point-source contamination were excluded from this assessment. VOC concentrations generally were low; 56% of the concentrations were less than 1 μg/L. In urban areas, 47% of the sampled wells had at least one VOC, and 29% had two or more VOCs; furthermore, U.S. Environmental Protection Agency drinking-water criteria were exceeded in 6.4% of all sampled wells and in 2.5% of the sampled drinking-water wells. In rural areas, 14% of the sampled wells had at least one VOC; furthermore, drinking-water criteria were exceeded in 1.5% of all sampled wells and in 1.3% of the sampled drinking-water wells. Solvent compounds and the fuel oxygenate methyl tert-butyl ether were among the most frequently detected VOCs in urban and rural areas. It was determined that the probability of finding VOCs in untreated groundwater can be estimated on the basis of a logistic regression model by using population density as an explanatory variable. Although there are limitations to this national scale model, it fit the data from 2354 wells used for model development and adequately estimated the VOC presence in samples from 589 wells used for model validation. Model estimates indicate that 7% (6−9% on the basis of one standard error) of the ambient groundwater resources of the United States probably contain at least one VOC at a reporting level of 0.2 μg/L. Groundwater is used in these areas by 42 million people (35−50

  2. Groundwater Quality Data in the Mojave Study Unit, 2008: Results from the California GAMA Program

    USGS Publications Warehouse

    Mathany, Timothy M.; Belitz, Kenneth

    2009-01-01

    Groundwater quality in the approximately 1,500 square-mile Mojave (MOJO) study unit was investigated from February to April 2008, as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). MOJO was the 23rd of 37 study units to be sampled as part of the GAMA Priority Basin Project. The MOJO study was designed to provide a spatially unbiased assessment of the quality of untreated ground water used for public water supplies within MOJO, and to facilitate statistically consistent comparisons of groundwater quality throughout California. Samples were collected from 59 wells in San Bernardino and Los Angeles Counties. Fifty-two of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study area (grid wells), and seven were selected to aid in evaluation of specific water-quality issues (understanding wells). The groundwater samples were analyzed for a large number of organic constituents [volatile organic compounds (VOCs), pesticides and pesticide degradates, and pharmaceutical compounds], constituents of special interest (perchlorate and N-nitrosodimethylamine [NDMA]) naturally occurring inorganic constituents (nutrients, dissolved organic carbon [DOC], major and minor ions, silica, total dissolved solids [TDS], and trace elements), and radioactive constituents (gross alpha and gross beta radioactivity, radium isotopes, and radon-222). Naturally occurring isotopes (stable isotopes of hydrogen, oxygen, and carbon, stable isotopes of nitrogen and oxygen in nitrate, and activities of tritium and carbon-14), and dissolved noble gases also were measured to help identify the sources and ages of the sampled

  3. Kansas City Plant ultraviolet/ozone/hydrogen peroxide groundwater treatment system overview

    SciTech Connect

    Stites, M.E.; Hughes, R.F.

    1992-04-01

    The Kansas City Plant (KCP) has committed to the utilization of a groundwater treatment system, for removal of volatile organic compounds (VOCs), that discharges a minimal amount of pollutants to the environment. An advanced oxidation process (AOP) system utilizing ozone, ultraviolet radiation, and hydrogen peroxide serves in this capacity. Packed tower aeration and activated carbon filtration are listed as best available technologies (BATs) by the Environmental Protection Agency (EPA) for the removal of VOCs in water. The disadvantage to these BATs is that they transfer the VOCs from the water medium to the air or carbon media respectively. Operation of the system began in May 1988 at a flow rate of 22.7 liters per minute (lpm) (6 gallons per minute (gpm)). An additional 102.2 lpm (27 gpm) of flow were added in October 1990. Various efforts to optimize and track the treatment unit`s efficiency have been carried out. A maximum influent reading of 26,590 parts per billion (ppb) of total VOCs has been recorded. Following the addition of flows, removal efficiency has averaged approximately 95%. Both air and water effluents are factored into this calculation.

  4. IN SITU TREATMENT OF SOIL AND GROUNDWATER CONTAMINATED WITH CHROMIUM - TECHNICAL RESOURCE GUIDE

    EPA Science Inventory

    New information and treatment approaches have been developed for chromium-contaminated soil and groundwater treatment. The prupose of this report is to bring together the most current information pertaining to the science of chromium contamination and the insitu treatment and co...

  5. Perchlorate Data for Streams and Groundwater in Selected Areas of the United States, 2004

    USGS Publications Warehouse

    Kalkhoff, Stephen J.; Stetson, Sarah J.; Lund, Kris D.; Wanty, Richard B.; Linder, Gregory L.

    2010-01-01

    This report presents data collected as part of a reconnaissance study to evaluate the occurrence of perchlorate in rivers and streams and in shallow aquifers in selected areas of the United States. Perchlorate, a component in rocket fuels, fireworks, and some explosives is soluble in water and persists in soils and water for long periods. It is biologically active at relatively low-levels in the environment, and has been identified as an endocrine-disrupting chemical. The purpose of this reconnaissance was to determine the occurrence of perchlorate in agricultural areas of the Midwestern and North-Central United States and in arid Central and Western parts of the United States. Samples were collected from 171 sites on rivers and streams and 146 sites from wells during the summer and early fall of 2004. Samples were collected from surface-water sites in 19 states and from wells in 5 states. Perchlorate was detected in samples collected in 15 states and was detected in 34 of 182 samples from rivers and streams and in 64 of 148 groundwater samples at concentrations equal to or greater than 0.4 micrograms per liter. Perchlorate concentrations were 1.0 micrograms per liter or greater in surface-water samples from seven states and in groundwater samples in four states. Only one surface-water and one groundwater sample had concentrations greater than 5.0 micrograms per liter. Perchlorate concentrations in followup samples collected from 1 to 3 months after the initial sample were unchanged at four of five stream sites.

  6. Groundwater Monitoring Report Central Nevada Test Area, Corrective Action Unit 443

    SciTech Connect

    2008-04-01

    This report presents the 2007 groundwater monitoring results collected by the U.S. Department of Energy (DOE) Office of Legacy Management (LM) for the Central Nevada Test Area (CNTA) Corrective Action Unit (CAU) 443. Responsibility for the environmental site restoration of the CNTA was transferred from the DOE Office of Environmental Management (DOE-EM) to DOE-LM on October 1, 2006. Requirements for CAU 443 are specified in the Federal Facility Agreement and Consent Order (FFACO 2005) entered into by DOE, the U.S. Department of Defense, and the State of Nevada and includes groundwater monitoring in support of site closure. This is the first groundwater monitoring report prepared by DOE-LM for the CNTA The CNTA is located north of U.S. Highway 6, approximately 30 miles north of Warm Springs in Nye County, Nevada (Figure 1). Three emplacement boreholes, UC-1, UC-3, and UC-4, were drilled at the CNTA for underground nuclear weapons testing. The initial underground nuclear test, Project Faultless, was conducted in borehole UC-1 at a depth of 3,199 feet (ft) (975 meters) below ground surface on January 19, 1968. The yield of the Project Faultless test was estimated to be 0.2 to 1 megaton (DOE 2004). The test resulted in a down-dropped fault block visible at land surface (Figure 2). No further testing was conducted at the CNTA, and the site was decommissioned as a testing facility in 1973.

  7. Implications of Prospective Climate Change for Groundwater Recharge in the Western United States

    NASA Astrophysics Data System (ADS)

    Meixner, T.; Manning, A. H.; Stonestrom, D. A.; Ajami, H.; Allen, D. M.; Blasch, K. W.; Brookfield, A. E.; Castro, C. L.; Clark, J. F.; Flint, A. L.; Neff, K.; Niraula, R.; Rodell, M.; Scanlon, B. R.; Singha, K.; Walvoord, M. A.

    2014-12-01

    Groundwater accounts for 25% of the United States' total water supply. Despite this importance, research efforts related to the impact of climate change on water resources have focused on surface water projections. Here we present results from a United States Geological Survey John Wesley Powell Center Group that synthesized current knowledge on groundwater recharge and the impact of climate change on recharge across the western US (west of 100o longitude). The specific aquifers considered included the High Plains Aquifer, San Pedro basin, Death Valley regional flow system, Wasatch Front aquifers, Central Valley Aquifer, Columbia Plateau Aquifer system, Spokane Valley-Rathdrum Prairie Glacial Aquifer, Williston basin and a regional overview of research on mountain aquifer systems. Combining existing studies on projected climate-change effects on recharge (available for half of the chosen systems) with expert knowledge of the remaining systems, several key patterns emerge across the region. First, our estimates indicate declines in recharge across the southern aquifers of 10-20% on average but with a wide range of uncertainty that surrounds zero change. Second, the northern tier of aquifers will likely see no change to slight increases in recharge. Third, mountain system recharge is expected to decline across the entire region due to changes in winter precipitation leading to decreased snowpack. Several critical knowledge gaps contributed uncertainty to our estimates. First, more studies coupling climate projections to groundwater systems are needed. Second, a generally poor understanding of mountain system processes is a source of significant uncertainty. Third, the response of focused recharge to potential changes in precipitation intensity and frequency is uncertain due to a lack of process understanding and the limited ability of climate projections to forecast changes in precipitation. Finally, feedbacks between climate, irrigation practices, and recharge

  8. Ground-water resources of the Bengasi area, Cyrenaica, United Kingdom of Libya

    USGS Publications Warehouse

    Doyel, William Watson; Maguire, Frank J.

    1964-01-01

    The Benpsi area of Libya, in the northwestern part of the Province of Cyrenaica (Wilayat Barqah), is semiarid, and available ground-water supplies in the area are relatively small. Potable ground water from known sources is reserved for the present and future needs of the city, and no surface-water supplies are available in the area. This investigation to evaluate known, as well as potential, water supplies in the area was undertaken as part of a larger program of ground-water investigations in Libya under the auspices of the U. S. Operations Mission to Libya and the Government of Libya. A ground-water reservoir underlies the Bengasi area, in which the water occurs in solution channels, cavities, and other openings in Miocene limestone. The reservoir is recharged directly by rainfall on the area and by infiltration from ephemeral streams (wadis) rising in Al Jabal al Akhar to the east. In the Baninah and Al Fuwayhit areas the ground-water reservoir yields water of fair quality and in sufficient quantity for the current (1959) needs. of the Bengasi city supply. The test-drilling program in the area south and southeast of Bengasi indicates that water in sufficient quantity for additional public supply probably can be obtained in some localities from wells. The water, however, is moderately to highly mineralized and would require treatment or demineralization before it could be used for additional public supply. Much of the water could be used directly for irrigation, but careful attention would have to be given to cultivation, drainage, and cropping practices. The hazard of saltwater encroachment also exists if large-scale withdrawals are undertaken in the coastal zones.

  9. Groundwater-Quality Data in the South Coast Range-Coastal Study Unit, 2008: Results from the California GAMA Program

    USGS Publications Warehouse

    Mathany, Timothy M.; Burton, Carmen A.; Land, Michael; Belitz, Kenneth

    2010-01-01

    Groundwater quality in the approximately 766-square-mile South Coast Range-Coastal (SCRC) study unit was investigated from May to December 2008, as part of the Priority Basins Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basins Project was developed in response to legislative mandates (Supplemental Report of the 1999 Budget Act 1999-00 Fiscal Year; and, the Groundwater Quality Monitoring Act of 2001 [Sections 10780-10782.3 of the California Water Code, Assembly Bill 599]) to assess and monitor the quality of groundwater in California, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The SCRC study unit was the 25th study unit to be sampled as part of the GAMA Priority Basins Project. The SCRC study unit was designed to provide a spatially unbiased assessment of untreated groundwater quality in the primary aquifer systems and to facilitate statistically consistent comparisons of untreated groundwater quality throughout California. The primary aquifer systems (hereinafter referred to as primary aquifers) were defined as that part of the aquifer corresponding to the perforation interval of wells listed in the California Department of Public Health (CDPH) database for the SCRC study unit. The quality of groundwater in shallow or deep water-bearing zones may differ from the quality of groundwater in the primary aquifers; shallow groundwater may be more vulnerable to surficial contamination. In the SCRC study unit, groundwater samples were collected from 70 wells in two study areas (Basins and Uplands) in Santa Barbara and San Luis Obispo Counties. Fifty-five of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells), and 15 wells were selected to aid in evaluation of specific water-quality issues (understanding wells). In addition to

  10. Geochemistry and Microbial Communities in Iron- and Manganese-Enriched Cold Groundwater Biofiltration Units

    NASA Astrophysics Data System (ADS)

    Chang, W.; Dangeti, S.; Roshani, B.; McBeth, J. M.

    2015-12-01

    Exploring how to enhance the microbially mediated oxidization of iron (Fe) and manganese (Mn) in natural and engineered environments in cold climates requires an understanding of the interactive relationships between the geochemistry of cold groundwater and Fe- and Mn-oxidizing bacteria. This study precisely measured geochemical and microbial communities in a scaled-up biofiltration system using synchrotron-based X-ray Absorption Near-Edge Spectroscopy (XANES) analyses coupled with next-generation sequencing (Illumina Miseq). Two pilot-scale biofiltration columns for Fe (Filter 1) and Mn (Filter 2) were connected in series and installed at the Langham Water Treatment Plant in Saskatoon, Canada. The groundwater temperature ranged from 4 to 8 °C. The pilot-scale study showed that successful treatment (99% removal) of both Fe and Mn was achieved in the biofilters. However, the Mn removal was significantly retarded for four months, likely due to the slow growth of Mn-oxidizing bacteria (MnOB) in Filter 2. The removal of Mn was accelerated once the redox potential in Filter 2 exceeded +300 mV. At that point, the XANES analyses showed that the oxidization states of Mn in Filter 2 were mainly +3 and +4, confirming that Mn oxidization had occurred. Geochemical analyses (PHREEQCi) also indicated changed geochemical conditions that favoured the formation of Mn-oxides during biofiltration. Next-generation sequencing analyses indicated the enrichment of iron-oxidizing bacteria (FeOB), including Gallionella sp. and Sideroxydans sp., in Filter 1. There were high read numbers for MnOB relatives, including Pseudomonas sp., Hydrogenophaga sp., Bdellovibrio sp., and Leptothrix sp., in Filter 2. Furthermore, the addition of anthracite (coal-based filter media) positively affected the growth MnOB and enhanced Mn oxidization. The evidence obtained in this study provides insight into how Mn oxidization can be accelerated in cold groundwater treatment systems.

  11. Hydrogeologic Framework of Bedrock Units and Initial Salinity Distribution for a Simulation of Groundwater Flow for the Lake Michigan Basin

    USGS Publications Warehouse

    Lampe, David C.

    2009-01-01

    The U.S. Geological Survey is assessing groundwater availability in the Lake Michigan Basin. As part of the assessment, a variable-density groundwater-flow model is being developed to simulate the effects of groundwater use on water availability throughout the basin. The hydrogeologic framework for the Lake Michigan Basin model was developed by grouping the bedrock geology of the study area into hydrogeologic units on the basis of the functioning of each unit as an aquifer or confining layer within the basin. Available data were evaluated based on the areal extent of coverage within the study area, and procedures were established to characterize areas with sparse data coverage. Top and bottom altitudes for each hydrogeologic unit were interpolated in a geographic information system for input to the model and compared with existing maps of subsurface formations. Fourteen bedrock hydrogeologic units, making up 17 bedrock model layers, were defined, and they range in age from the Jurassic Period red beds of central Michigan to the Cambrian Period Mount Simon Sandstone. Information on groundwater salinity in the Lake Michigan Basin was compiled to create an input dataset for the variable-density groundwater-flow simulation. Data presented in this report are referred to as 'salinity data' and are reported in terms of total dissolved solids. Salinity data were not available for each hydrogeologic unit. Available datasets were assigned to a hydrogeologic unit, entered into a spatial database, and data quality was visually evaluated. A geographic information system was used to interpolate salinity distributions for each hydrogeologic unit with available data. Hydrogeologic units with no available data either were set equal to neighboring units or were vertically interpolated by use of values from units above and below.

  12. Compilation of Regional Ground-Water Divides for Principal Aquifers Corresponding to the Great Lakes Basin, United States

    USGS Publications Warehouse

    Sheets, R.A.; Simonson, L.A.

    2006-01-01

    A compilation of regional ground-water divides for the five principal aquifers corresponding to the Great Lakes Basin within the United States is presented. The principal aquifers (or aquifer systems) are the Cambrian-Ordovician aquifer system, Silurian-Devonian aquifers, Mississippian aquifers, Pennsylvanian aquifers, and the surficial aquifer system. The regional ground-water divides mark the boundary between ground-water flow that discharges to the Great Lakes or their tributaries and ground-water flow that discharges to other major surface-water bodies, such as the Mississippi River. Multicounty to multistate (regional) hydrologic studies of the five principal aquifers were reviewed to determine whether adequate data, such as potentiometric surfaces or ground-water divides, were available from which ground-water flow directions or ground-water-divide locations could be derived. Examination of regional studies indicate that the regional ground-water divides for the Cambrian-Ordovician aquifer system and Silurian-Devonian aquifers have changed over time and differ from the surface-water divides in some areas. These differences can be attributed to either pumping or natural processes. The limited information on the shallow Mississippian and Pennsylvanian bedrock aquifers indicate that these aquifers and the surficial aquifer system act as one hydrostratigraphic unit and that downdip flow is insignificant. Generally, in the Mississippian and Pennsylvanian aquifers, regional ground-water divides are similar to regional surface-water divides. Previous studies of the regional ground-water divide of the surficial aquifer system depict the regional ground-water divide as generally following the regional surface-water divide. Because studies commonly focus on areas where ground-water use from an aquifer system is concentrated, the regional ground-water divides are not known in large, unstudied parts of some of these aquifer systems. A composite ground-water divide for

  13. Toxicological and chemical assessment of arsenic-contaminated groundwater after electrochemical and advanced oxidation treatments.

    PubMed

    Radić, Sandra; Crnojević, Helena; Vujčić, Valerija; Gajski, Goran; Gerić, Marko; Cvetković, Želimira; Petra, Cvjetko; Garaj-Vrhovac, Vera; Oreščanin, Višnja

    2016-02-01

    Owing to its proven toxicity and mutagenicity, arsenic is regarded a principal pollutant in water used for drinking. The objective of this study was the toxicological and chemical evaluation of groundwater samples obtained from arsenic enriched drinking water wells before and after electrochemical and ozone-UV-H2O2-based advanced oxidation processes (EAOP). For this purpose, acute toxicity test with Daphnia magna and chronic toxicity test with Lemna minor L. were employed as well as in vitro bioassays using human peripheral blood lymphocytes (HPBLs). Several oxidative stress parameters were estimated in L.minor. Physicochemical analysis showed that EAOP treatment was highly efficient in arsenic but also in ammonia and organic compound removal from contaminated groundwater. Untreated groundwater caused only slight toxicity to HPBLs and D. magna in acute experiments. However, 7-day exposure of L. minor to raw groundwater elicited genotoxicity, a significant growth inhibition and oxidative stress injury. The observed genotoxicity and toxicity of raw groundwater samples was almost completely eliminated by EAOP treatment. Generally, the results obtained with L. minor were in agreement with those obtained in the chemical analysis suggesting the sensitivity of the model organism in monitoring of arsenic-contaminated groundwater. In parallel to chemical analysis, the implementation of chronic toxicity bioassays in a battery is recommended in the assessment of the toxic and genotoxic potential of such complex mixtures. PMID:26580737

  14. Kansas City Plant ultraviolet/ozone/hydrogen peroxide groundwater treatment system overview

    SciTech Connect

    Stites, M.E.; Hughes, R.F.

    1992-04-01

    The Kansas City Plant (KCP) has committed to the utilization of a groundwater treatment system, for removal of volatile organic compounds (VOCs), that discharges a minimal amount of pollutants to the environment. An advanced oxidation process (AOP) system utilizing ozone, ultraviolet radiation, and hydrogen peroxide serves in this capacity. Packed tower aeration and activated carbon filtration are listed as best available technologies (BATs) by the Environmental Protection Agency (EPA) for the removal of VOCs in water. The disadvantage to these BATs is that they transfer the VOCs from the water medium to the air or carbon media respectively. Operation of the system began in May 1988 at a flow rate of 22.7 liters per minute (lpm) (6 gallons per minute (gpm)). An additional 102.2 lpm (27 gpm) of flow were added in October 1990. Various efforts to optimize and track the treatment unit's efficiency have been carried out. A maximum influent reading of 26,590 parts per billion (ppb) of total VOCs has been recorded. Following the addition of flows, removal efficiency has averaged approximately 95%. Both air and water effluents are factored into this calculation.

  15. FEASIBILITY STUDY REPORT FOR THE 200-ZP-1 GROUNDWATER OPERABLE UNIT

    SciTech Connect

    BYRNES ME

    2008-07-18

    The Hanford Site, managed by the U.S. Department of Energy (DOE), encompasses approximately 1,517 km{sup 2} (586 mi{sup 2}) in the Columbia Basin of south-central Washington State. In 1989, the U.S. Environmental Protection Agency (EPA) placed the 100, 200, 300, and 1100 Areas of the Hanford Site on the 40 Code of Federal Regulations (CFR) 300, 'National Oil and Hazardous Substances Pollution Contingency Plan' National Contingency Plan [NCPD], Appendix B, 'National Priorities List' (NPL), pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). The 200 Areas NPL sites consist of the 200 West and 200 East Areas (Figure 1-1). The 200 Areas contain waste management facilities, inactive irradiated fuel reprocessing facilities, and the 200 North Area (formerly used for interim storage and staging of irradiated fuel). Several waste sites in the 600 Area, located near the 200 Areas, also are included in the 200 Areas NPL site. The 200 Areas NPL site is in a region referred to as the 'Central Plateau' and consists of approximately 700 waste sites, excluding sites assigned to the tank farm waste management areas (WMAs). The 200-ZP-1 Groundwater Operable Unit (OU) consists of the groundwater located under the northern portion of the 200 West Area. Waste sources that contributed to the 200-ZP-1 OU included cribs and trenches that received liquid and/or solid waste in the past from the Z Plant and T Plant aggregate areas, WMA-T, WMA-TX/TY, and the State-Approved Land Disposal Site (SALDS). This feasibility study (FS) for the 200-ZP-1 Groundwater OU was prepared in accordance with the requirements of CERCLA decision documents. These decision documents are part of the Administrative Record for the selection of remedial actions for each waste site and present the selected remedial actions that are chosen in accordance with CERCLA, as amended by the Superfund Amendments and Reauthorization Act of 1986, and to the extent practicable

  16. Geomatics for Mapping of Groundwater Potential Zones in Northern Part of the United Arab Emiratis - Sharjah City

    NASA Astrophysics Data System (ADS)

    Al-Ruzouq, R.; Shanableh, A.; Merabtene, T.

    2015-04-01

    In United Arab Emirates (UAE) domestic water consumption has increased rapidly over the last decade. The increased demand for high-quality water, create an urgent need to evaluate the groundwater production of aquifers. The development of a reasonable model for groundwater potential is therefore crucial for future systematic developments, efficient management, and sustainable use of groundwater resources. The objective of this study is to map the groundwater potential zones in northern part of UAE and assess the contributing factors for exploration of potential groundwater resources. Remote sensing data and geographic information system will be used to locate potential zones for groundwater. Various maps (i.e., base, soil, geological, Hydro-geological, Geomorphologic Map, structural, drainage, slope, land use/land cover and average annual rainfall map) will be prepared based on geospatial techniques. The groundwater availability of the basin will qualitatively classified into different classes based on its hydro-geo-morphological conditions. The land use/land cover map will be also prepared for the different seasons using a digital classification technique with a ground truth based on field investigation.

  17. Groundwater-quality data for the Sierra Nevada study unit, 2008: Results from the California GAMA program

    USGS Publications Warehouse

    Shelton, Jennifer L.; Fram, Miranda S.; Munday, Cathy M.; Belitz, Kenneth

    2010-01-01

    Groundwater quality in the approximately 25,500-square-mile Sierra Nevada study unit was investigated in June through October 2008, as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The Sierra Nevada study was designed to provide statistically robust assessments of untreated groundwater quality within the primary aquifer systems in the study unit, and to facilitate statistically consistent comparisons of groundwater quality throughout California. The primary aquifer systems (hereinafter, primary aquifers) are defined by the depth of the screened or open intervals of the wells listed in the California Department of Public Health (CDPH) database of wells used for public and community drinking-water supplies. The quality of groundwater in shallower or deeper water-bearing zones may differ from that in the primary aquifers; shallow groundwater may be more vulnerable to contamination from the surface. In the Sierra Nevada study unit, groundwater samples were collected from 84 wells (and springs) in Lassen, Plumas, Butte, Sierra, Yuba, Nevada, Placer, El Dorado, Amador, Alpine, Calaveras, Tuolumne, Madera, Mariposa, Fresno, Inyo, Tulare, and Kern Counties. The wells were selected on two overlapping networks by using a spatially-distributed, randomized, grid-based approach. The primary grid-well network consisted of 30 wells, one well per grid cell in the study unit, and was designed to provide statistical representation of groundwater quality throughout the entire study unit. The lithologic grid-well network is a secondary grid that consisted of the wells in the primary grid-well network plus 53 additional wells and was designed to provide statistical representation of groundwater quality in each of the four major lithologic units in the Sierra

  18. Groundwater treatment in a field pilot methanotrophic rotating biological contactor

    SciTech Connect

    Belcher, D.M.; Vira, A.; Dooley, M.A.; Johnson, J.C.

    1995-12-31

    A pilot-scale rotating biological contactor (RBC) was operated under field conditions for approximately 1 month to remove chlorinated and nonchlorinated organic compounds from groundwater. Methanotrophic conditions were successfully established and maintained in the RBC during the field program. Results of the pilot program indicated that low concentrations of cis-1,2-dichloroethene (cis-DCE) and vinyl chloride could be treated to below the maximum contaminant levels (MCLs) of 70 ad 2 {micro}g/L, respectively. Maximum removal rates for cis-DCE and vinyl chloride measured during the pilot study were 2.14 {micro}g cis-DCE/ft{sup 2} disc media-minute (952 {micro}g cis-DCE/mg volatile solids [VS]-day) and 0.3 {micro}g vinyl chloride/ft{sup 2}-minute (143 {micro}g vinyl chloride/mg VS-day), respectively. Chlorinated ethene removal efficiencies decreased after the first 2 weeks of operation. Low concentrations of toluene, ethylbenzene, and total xylenes (TEX) were effectively removed from groundwater throughout the course of the pilot study. The maximum observed TEX removal rate was 3.0 {micro}g TEX/ft{sup 2}-minute.

  19. Installation of reactive metals groundwater collection and treatment systems

    SciTech Connect

    Hopkins, J.K.; Primrose, A.L.; Vogan, J.; Uhland, J.

    1998-07-01

    Three groundwater plumes contaminated with volatile organic compounds (VOCs) and radionuclides at the Rocky Flats Environmental Technology Site are scheduled for remediation by 1999 based on the Rocky Flats Cleanup Agreement (RFCA) (DOE, 1996). These three plumes are among the top 20 environmental cleanup sites at Rocky Flats. One of these plumes, the Mound Site Plume, is derived from a previous drum storage area, and daylights as seeps near the South Walnut Creek drainage. Final design for remediation of the Mound Site Plume has been completed based on use of reactive metals to treat the contaminated groundwater, and construction is scheduled for early 1998. The two other plumes, the 903 Pad/Ryan`s Pit and the East Trenches Plumes, are derived from VOCs either from drums that leaked or that were disposed of in trenches. These two plumes are undergoing characterization and conceptual design in 1998 and construction is scheduled in 1999. The contaminants of concern in these plumes are tetrachloroethene, trichloroethene, carbon tetrachloride and low levels of uranium and americium.

  20. Widespread elevated atmospheric SF 6 mixing ratios in the Northeastern United States: Implications for groundwater dating

    NASA Astrophysics Data System (ADS)

    Santella, Nicholas; Ho, David T.; Schlosser, Peter; Stute, Martin

    2008-01-01

    SummarySF 6 is a promising transient tracer for groundwater dating, but elevated levels of atmospheric SF 6 may limit application of this dating method in urban areas. To determine the magnitude of this limitation within the United States (US), this study derives average atmospheric SF 6 mixing ratios from soil air measurements from five major urban areas. All surveyed sites showed SF 6 elevated above Northern Hemisphere clean air levels. In many cases, SF 6 mixing ratios were highest within large cities, but significantly elevated levels persisted hundreds of kilometers beyond the urban centers. Estimated SF 6 emissions from New York city were anomalously large, resulting in average levels over 200% above remote atmosphere values. Emissions from other urban areas included in this study appear to be typical for large cities in the US and maximum observed elevations of SF 6, in these areas, were in the range of 50-100%. These findings imply that caution is needed in choosing an atmospheric input function when using SF 6 as a transient tracer within or near urbanized regions. Within the Northeast US, the assumption of remote atmospheric SF 6 may lead to significant errors in estimation of groundwater ages, especially in the case of an expected future flattening of the atmospheric mixing ratio curve.

  1. Application of uphole data from petroleum seismic surveys to groundwater investigations, Abu Dhabi (United Arab Emirates)

    USGS Publications Warehouse

    Woodward, D.; Menges, C.M.

    1991-01-01

    Velocity data from uphole surveys were used to map the water table and the contact at the base dune sand/top alluvium as part of a joint National Drilling Company-United States Geological Survey Ground Water Research Project in the Emirate of Abu Dhabi. During 1981-1983, a reconnaissance seismic survey was conducted for petroleum exploration in the eastern region of Abu Dhabi. Approximately 2800 kilometers of seismic data, consisting of 92 lines, were acquired in the 2500 km2 concession area near Al Ain. Uphole surveys were conducted about 2 km apart along each seismic line, and were used to calculate weathering corrections required to further process in the seismic data. Approximately 1300 uphole surveys were completed in the concession area between March 1981 and June 1983. Reinterpretation of the velocity profiles derived from the uphole surveys provided data for determining the following subsurface layers, listed in descending order: (1) a surficial, unconsolidated weathering layer with a velocity from 300 to 450 m/s; (2) surficial dune sand, from 750 to 900 m/s; (3) unsaturated, unconsolidated alluvium, from 1000 to 1300 m/s; and (4) saturated, unconsolidated alluvium, from 1900 to 2200 m/s. Two interfaces-the water table and the base dune sand/top alluvium - were identified and mapped from boundaries between these velocity layers. Although the regional water table can fluctuate naturally as much as 3 m per year in this area and the water-table determinations from the uphole data span a 27-month period, an extremely consistent and interpretable water-table map was derived from the uphole data throughout the entire concession area. In the northern part of the area, unconfined groundwater moves northward and northwestward toward the Arabian Gulf; and in the central and southern parts of the area, groundwater moves westward away from the Oman Mountains. In the extreme southern area east of Jabal Hafit, groundwater moves southward into Oman. The map of the base

  2. 2009 Groundwater Monitoring Report Project Shoal Area, Corrective Action Unit 447

    SciTech Connect

    2010-03-01

    This report presents the 2009 groundwater monitoring results collected by the U.S. Department of Energy (DOE) Office of Legacy Management (LM) at the Project Shoal Area (PSA) Subsurface Corrective Action Unit (CAU) 447 in Churchill County, Nevada. Responsibility for the environmental site restoration of the PSA was transferred from the DOE Office of Environmental Management to LM on October 1, 2006. The environmental restoration process and corrective action strategy for CAU 447 are conducted in accordance with the Federal Facility Agreement and Consent Order (FFACO 1996, as amended February 2008) entered into by DOE, the U.S. Department of Defense, and the State of Nevada. The corrective action strategy for the site includes monitoring in support of site closure. This report summarizes investigation activities associated with CAU 447 that were conducted at the PSA during fiscal year 2009.

  3. Data validation report for the 100-HR-3 Operable Unit first quarter 1994 groundwater sampling data

    SciTech Connect

    Biggerstaff, R.L.

    1994-06-24

    Westinghouse-Hanford has requested that a minimum of 20% of the total number of Sample Delivery Groups be validated for the 100-HR-3 Operable Unit First Quarter 1994 Groundwater Sampling Investigation. Therefore, the data from the chemical analysis of twenty-four samples from this sampling event and their related quality assurance samples were reviewed and validated to verify that reported sample results were of sufficient quality to support decisions regarding remedial actions performed at this site. The samples were analyzed by Thermo-Analytic Laboratories (TMA) and Roy F. Weston Laboratories (WESTON) using US Environmental Protection Agency (EPA) CLP protocols. Sample analyses included: inorganics; and general chemical parameters. Forty-two samples were validated for radiochemical parameters by TMA and Teledyne.

  4. Status of groundwater quality in the San Fernando--San Gabriel study unit, 2005--California GAMA Priority Basin Project

    USGS Publications Warehouse

    Land, Michael; Kulongoski, Justin T.; Belitz, Kenneth

    2012-01-01

    Groundwater quality in the approximately 460-square-mile San Fernando--San Gabriel (FG) study unit was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study area is in Los Angeles County and includes Tertiary-Quaternary sedimentary basins situated within the Transverse Ranges of southern California. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The GAMA FG study was designed to provide a spatially unbiased assessment of the quality of untreated (raw) groundwater in the primary aquifer systems (hereinafter referred to as primary aquifers) throughout California. The assessment is based on water-quality and ancillary data collected in 2005 by the USGS from 35 wells and on water-quality data from the California Department of Public Health (CDPH) database. The primary aquifers were defined by the depth interval of the wells listed in the CDPH database for the FG study unit. The quality of groundwater in primary aquifers may be different from that in the shallower or deeper water-bearing zones; shallow groundwater may be more vulnerable to surficial contamination. This study assesses the status of the current quality of the groundwater resource by using data from samples analyzed for volatile organic compounds (VOCs), pesticides, and naturally occurring inorganic constituents, such as major ions and trace elements. This status assessment is intended to characterize the quality of groundwater resources in the primary aquifers of the FG study unit, not the treated drinking water delivered to consumers by water purveyors.

  5. Nitrate in groundwater of the midwestern United States: A regional investigation on relations to land use and soil properties

    USGS Publications Warehouse

    Kolpin, D.; Burkart, M.; Goolsby, D.

    1999-01-01

    The intense application of nitrogen-fertilizer to cropland in the midwestern United States has created concern about nitrate contamination of the region's aquifers. Since 1991, the US Geological Survey has used a network of 303 wells to investigate the regional distribution of nitrate in near-surface aquifers of the midwestern United States. Detailed land use and soil data were compiled within a 2 km radius of 100 unconsolidated wells in the regional network to determine relations to nitrate concentrations in groundwater. For land use, the amount of irrigated land was directly related to nitrate concentrations in groundwater. For soils, the general water table depth and soil factors associated with rates of water movement were directly related to nitrate concentrations in groundwater.

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

    USGS Publications Warehouse

    Alley, W.M.; Cohen, P.

    1991-01-01

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

  7. Wellhead treatment costs for groundwater contaminated with pesticides: A preliminary analysis for pineapple in Hawaii

    NASA Astrophysics Data System (ADS)

    Leon-Guerrero, Ephraim D.; Loague, Keith; Green, Richard E.

    1994-01-01

    In Hawaii, trace concentrations of pesticides used in the production of pineapple were found in the groundwater supplies of Mililani Town in the Pearl Harbor Basin on the island of Oahu. Groundwater serves as the major source of drinking water and residents pay for wellhead treatment of the contaminated water, via their monthly water bill. The agricultural chemical users within the Pearl Harbor Basin do not include these wellhead treatment costs in their production costs. The agricultural industry benefits from using pesticides but does not pay the entire societal cost of using these chemicals. In this study we evaluate the specific financial cost of wellhead treatment, and not the economic value of groundwater. While wellhead treatment costs could conceivably be shared by several parties, this study focuses on the financial impact of the pineapple industry alone. This study factors annual wellhead treatment costs into annual pineapple production costs to measure the effect on annual financial return from pineapple production. Wellhead treatment costs are calculated from the existing granulated activated carbon (GAC) water treatment facility for Millilani Wells I and II. Pineapple production costs are estimated from previous cost of production studies. The inclusion of wellhead treatment costs produces different production-cost results, depending on the scale of analysis. At the local scale, the Mililani wellhead treatment costs can be factored into the production costs of the pineapple fields, which were probably responsible for contamination of the Mililani Wells, without causing a deficit in economic return. At the larger regional scale, however, the return from all of the pineapple grown in the Pearl Harbor Basin can not sustain the cost of wellhead treatmentfor the entire water supply of the basin. Recommendations point to the prevention of groundwater contamination as more cost-effective measure than wellhead treatment.

  8. Field assessment of nanoscale bimetallic particles for groundwater treatment.

    PubMed

    Elliott, D W; Zhang, W X

    2001-12-15

    A field demonstration was performed in which nanoscale bimetallic (Fe/Pd) particles were gravity-fed into groundwater contaminated bytrichloroethene and other chlorinated aliphatic hydrocarbons at a manufacturing site. With diameters on the order of 100-200 nm, the nanoparticles are uniquely suited to rapidly degrade redox-amenable contaminants and for optimal subsurface delivery and dispersion. Approximately 1.7 kg of the nanoparticles was fed into the test area over a 2-day period, resulting in minimal clogging of the injection well. The test area was located within a well-characterized region of the contaminant plume and included an injection well and three piezometer couplets spaced 1.5 m apart. Despite the low nanoparticle dosage, trichloroethene reduction efficiencies of up to 96% were observed over a 4-week monitoring period with the highest values observed at the injection well and adjacent piezometers. Data from the field assessment were consistent with the results of pre-injection laboratory studies, which showed rapid dechlorination of target chlorinated compounds accompanied by a sharp decrease of standard oxidation potential and an increase in pH. PMID:11775172

  9. MANUAL: GROUND-WATER AND LEACHATE TREATMENT SYSTEMS

    EPA Science Inventory

    This manual was developed for remedial design engineers and regulatory personnel who oversee the ex situ ground water or leachate treatment efforts of the regulated community. The manual can be used as a treatment technology screening tool in conjunction with other references. Mo...

  10. In situ treatment of cyanide-contaminated groundwater by iron cyanide precipitation

    SciTech Connect

    Ghosh, R.S.; Dzombak, D.A.; Luthy, R.G.; Smith, J.R.

    1999-10-01

    Groundwater contamination with cyanide is common at many former or active industrial sites. Metal-cyanide complexes typically dominate aqueous speciation of cyanide in groundwater systems, with iron-cyanide complexes often most abundant. Typically, metal-cyanide complexes behave as nonadsorbing solutes in sand-gravel aquifer systems in the neutral pH range, rendering cyanide relatively mobile in groundwater systems. Groundwater pump-and-treat systems have often been used to manage cyanide contamination in groundwater. This study examined the feasibility of using in situ precipitation of iron cyanide in a reactive barrier to attenuate the movement of cyanide in groundwater. Laboratory column experiments were performed in which cyanide solutions were passed through mixtures of sand and elemental iron filings. Removal of dissolved cyanide was evaluated in a variety of cyanide-containing influents under various flow rates and sand-to-iron weight ratios. Long-term column tests performed with various cyanide-containing influents under both oxic and anoxic conditions, at neutral pH and at flow rates typical of sand-gravel porous media, yielded effluent concentrations of total cyanide as low as 0.5 mg/L. Effluent cyanide concentrations achieved were close to the solubilities of Turnbull's blue-hydrous ferric oxide solid solutions, indicating co-precipitation of the two solids. Maximum cyanide removal efficiency was achieved with approximately 10% by weight of iron in the sand-iron mixtures; higher iron contents did not increase removal efficiency significantly. Results obtained indicate that in situ precipitation is a promising passive treatment approach for cyanide in groundwater.

  11. Record of Decision for Tank Farm Soil and INTEC Groundwater, Operable Unit 3-14

    SciTech Connect

    L. S. Cahn

    2007-05-16

    This decision document presents the selected remedy for Operable Unit (OU) 3-14 tank farm soil and groundwater at the Idaho Nuclear Technology and Engineering Center (INTEC), which is located on the Idaho National Laboratory (INL) Site. The tank farm was initially evaluated in the OU 3-13 Record of Decision (ROD), and it was determined that additional information was needed to make a final decision. Additional information has been obtained on the nature and extent of contamination in the tank farm and on the impact to groundwater. The selected remedy was chosen in accordance with the Comprehensive Environmental Response, Liability and Compensation Act of 1980 (CERCLA) (42 USC 9601 et seq.), as amended by the Superfund Amendments and Reauthorization Act of 1986 (Public Law 99-499) and the National Oil and Hazardous Substances Pollution Contingency Plan (40 CFR 300). The selected remedy is intended to be the final action for tank farm soil and groundwater at INTEC. The response action selected in this ROD is necessary to protect the public health, welfare, or the environment from actual or threatened releases of hazardous substances into the environment. Such a release or threat of release may present an imminent and substantial endangerment to public health, welfare, or the environment. The remedial actions selected in this ROD are designed to reduce the potential threats to human health and the environment to acceptable levels. In addition, DOE-ID, EPA, and DEQ (the Agencies) have determined that no action is necessary under CERCLA to protect public health, welfare, or the environment at 16 sites located outside the tank farm boundary. The purposes of the selected remedy are to (1) contain contaminated soil as the radionuclides decay in place, (2) isolate current and future workers and biological receptors from contact with contaminated soil, and (3) restore the portion of Snake River Plain Aquifer contaminated by INTEC releases to Idaho Ground Water Quality

  12. Appraisal of ground-water quality near wastewater-treatment facilities, Glacier National Park, Montana

    USGS Publications Warehouse

    Moreland, Joe A.; Wood, Wayne A.

    1982-01-01

    Water-level and water-quality data were collected from monitoring wells at wastewater-treatment facilities in Glacier National Park. Five additional shallow observation wells were installed at the Glacier Park Headquarters facility to monitor water quality in the shallow ground-water system. Water-level, water-quality, and geologic information indicate that some of the initial monitoring wells are not ideally located to sample ground water most likely to be affected by waste disposal at the sites. Small differences in chemical characteristics between samples from monitor wells indicate that effluent may be affecting ground-water quality but that impacts are not significant. Future monitoring of ground-water quality could be limited to selected wells most likely to be impacted by percolating effluent. Laboratory analyses for common ions could detect future impacts. (USGS)

  13. Occurrence and transport of pharmaceuticals in a karst groundwater system affected by domestic wastewater treatment plants

    NASA Astrophysics Data System (ADS)

    Einsiedl, Florian; Radke, Michael; Maloszewski, Piotr

    2010-09-01

    The occurrence of two pharmaceuticals, ibuprofen and diclofenac, in a vulnerable karst groundwater system was investigated. The hydrogeology of the karst system was identified by collecting 3H samples in groundwater over 27 years and by performing tracer tests. The isotopes and tracer data were interpreted by mathematical modeling to estimate the mean transit time of water and to characterize the hydrogeological flow paths in the groundwater system. By this approach, a mean 3H transit time of 4.6 years for the fissured-porous karst aquifer was determined, whereas the fast flowing water in the conduit system showed a mean transit time of days. Both pharmaceuticals which infiltrated along sinkholes and small streams into the karst system were detected in concentrations of up to approximately 1 μg/L in effluent water of the wastewater treatment plants. Diclofenac was present in most samples collected from four springs discharging the karst groundwater to the rivers Altmühl and Anlauter in concentrations between 3.6 and 15.4 ng/L. In contrast, ibuprofen was rarely detected in groundwater. The results of this study suggest that both pharmaceuticals move into the fractured system of the karst system and go into storage. Thus dilution processes are the dominant control on the concentrations of both pharmaceuticals in the fractured system, whereas biodegradation is likely less important.

  14. Role of Climate Variability in Modulating Surface Water and Groundwater Interaction over the Southeast United States

    NASA Astrophysics Data System (ADS)

    Almanaseer, N.; Arumugam, S.; Bales, J. D.

    2010-12-01

    We investigate the role of climatic variability on interannual groundwater variability in the Southeast U.S. For this purpose, streamflow and associated groundwater levels are analyzed for 20 basins that are minimally affected by reservoirs and groundwater pumping. Using the spatially-averaged monthly precipitation time series obtained from the Precipitation Regressions on Independent Slope Model (PRISM), we identify the recharge and discharge periods that influence the groundwater levels during the winter (January-February-March, JFM) and summer (July-August-September, JAS) seasons. Recharge-discharge dependency analyses indicate that precipitation during the previous three months influence the groundwater level in a given month. Streamflow in any given month depends on the groundwater level during the previous three months. Singular spectrum analysis (SSA) on the precipitation, temperature, streamflow and groundwater data indicate that groundwater levels and streamflow are the two dominant variables influencing the basin hydroclimatology. Further, relating the percentage variance explained from the SSA to baseflow index (BFI) clearly show that basins with high BFI have higher eigenvalues indicating groundwater being a spatial integrator of hydroclimatic processes. Relating the groundwater levels with El Nino Southern Oscillation (ENSO) index, Nino3.4, show that interannual variability in JFM groundwater levels could be partially explained by the ENSO conditions, but the relationship between JAS groundwater levels and JAS Nino3.4 is statistically not significant. Investigating the ability of precipitation forecasts from ECHAM4.5 General Circulation Model shows that there is potential to quantify groundwater availability during the winter season based on the forecasted precipitation and ENSO conditions.

  15. Groundwater-Quality Data in the South Coast Interior Basins Study Unit, 2008: Results from the California GAMA Program

    USGS Publications Warehouse

    Mathany, Timothy M.; Kulongoski, Justin T.; Ray, Mary C.; Belitz, Kenneth

    2009-01-01

    Groundwater quality in the approximately 653-square-mile South Coast Interior Basins (SCI) study unit was investigated from August to December 2008, as part of the Priority Basins Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basins Project was developed in response to Legislative mandates (Supplemental Report of the 1999 Budget Act 1999-00 Fiscal Year; and, the Groundwater-Quality Monitoring Act of 2001 [Sections 10780-10782.3 of the California Water Code, Assembly Bill 599]) to assess and monitor the quality of groundwater used as public supply for municipalities in California, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). SCI was the 27th study unit to be sampled as part of the GAMA Priority Basins Project. This study was designed to provide a spatially unbiased assessment of the quality of untreated groundwater used for public water supplies within SCI, and to facilitate statistically consistent comparisons of groundwater quality throughout California. Samples were collected from 54 wells within the three study areas [Livermore, Gilroy, and Cuyama] of SCI in Alameda, Santa Clara, San Benito, Santa Barbara, Ventura, and Kern Counties. Thirty-five of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells), and 19 were selected to aid in evaluation of specific water-quality issues (understanding wells). The groundwater samples were analyzed for organic constituents [volatile organic compounds (VOCs), pesticides and pesticide degradates, polar pesticides and metabolites, and pharmaceutical compounds], constituents of special interest [perchlorate and N-nitrosodimethylamine (NDMA)], naturally occurring inorganic constituents [trace elements, nutrients, major and minor ions, silica, total dissolved solids (TDS), and alkalinity

  16. Evaluation of Zeolite Permeable Treatment Wall for the Removal of Strontium-90 from Groundwater

    NASA Astrophysics Data System (ADS)

    Seneca, S. M.; Bronner, C.; Ross, E.; Rabideau, A. J.

    2009-05-01

    Experimental and modeling studies have been initiated to evaluate the potential performance of a permeable treatment wall comprised of zeolite-rich rock for the removal of strontium-90 from groundwater. Preliminary column studies were performed using a synthetic groundwater referenced to anticipate field conditions, with a focus on quantifying the competitive ion exchange among five cations (Na+, K+, Ca2+, Mg2+, and Sr2+). Variations of the column configurations addressed the effects of particle size and flow rates on removal efficiency. In general, kinetic effects were not significant for the test conditions. Ongoing studies are focused on the comparison of zeolites obtained from two sources: Teague Mineral Products (Adrian, OR) and Bear River Zeolite (Preston, UT), and on the possible influence of native soil that is mixed with treatment wall material during construction. The results of the performance assessment will support the possible deployment of a full scale treatment wall at a Western New York nuclear facility.

  17. In situ treatment of arsenic-contaminated groundwater by air sparging.

    PubMed

    Brunsting, Joseph H; McBean, Edward A

    2014-04-01

    Arsenic contamination of groundwater is a major problem in some areas of the world, particularly in West Bengal (India) and Bangladesh where it is caused by reducing conditions in the aquifer. In situ treatment, if it can be proven as operationally feasible, has the potential to capture some advantages over other treatment methods by being fairly simple, not using chemicals, and not necessitating disposal of arsenic-rich wastes. In this study, the potential for in situ treatment by injection of compressed air directly into the aquifer (i.e. air sparging) is assessed. An experimental apparatus was constructed to simulate conditions of arsenic-rich groundwater under anaerobic conditions, and in situ treatment by air sparging was employed. Arsenic (up to 200 μg/L) was removed to a maximum of 79% (at a local point in the apparatus) using a solution with dissolved iron and arsenic only. A static "jar" test revealed arsenic removal by co-precipitation with iron at a molar ratio of approximately 2 (iron/arsenic). This is encouraging since groundwater with relatively high amounts of dissolved iron (as compared to arsenic) therefore has a large theoretical treatment capacity for arsenic. Iron oxidation was significantly retarded at pH values below neutral. In terms of operation, analysis of experimental results shows that periodic air sparging may be feasible. PMID:24561624

  18. Preliminary assessment of the occurrence and possible sources of MTBE in groundwater in the United States, 1993-1994

    USGS Publications Warehouse

    Squillace, P.J.; Zogorski, J.S.; Wilber, W.G.; Price, C.V.

    1996-01-01

    The 1990 Clean Air Act Amendments require fuel oxygenates to be added to gasoline used in some metropolitan areas to reduce atmospheric concentrations of carbon monoxide or ozone. Methyl tert-butyl ether (MTBE) is the most commonly used fuel oxygenate and is a relatively new gasoline additive. Nevertheless, out of 60 volatile organic chemicals analyzed, MTBE was the second most frequently detected chemical in samples of shallow ambient groundwater from urban areas that were collected during 1993-1994 aspart of the U.S. Geological Survey's National Water-Quality Assessment program. Samples were collected from five drinking water wells, 12 springs, and 193 monitoring wells in urban areas. No MTBE was detected in drinking water wells. At a reporting level of 0.2 ??g/L, MTBE was detected most frequently in shallow groundwater from urban areas (27% of 210 wells and springs sampled in eight areas) as compared to shallow groundwater from agricultural areas (1.3% of 549 wells sampled in 21 areas) or deeper groundwater from major aquifers (1.0% of 412 wells sampled in nine areas). Only 3% of the shallow wells sampled in urban areas had concentrations of MTBE that exceed 20 ??g/L, which is the estimated lower limit of the United States Environmental Protection Agency draft drinking water health advisory. Because MTBE is persistent and mobile in groundwater, it can move from shallow to deeper aquifers with time. In shallow urban groundwater, MTBE generally was not found with benzene, toluene, ethylbenzene, or xylene (BTEX) compounds, which commonly are associated with gasoline spills. This disassociation causes uncertainty as to the source of MTBE. Possible sources of MTBE in groundwater include point sources, such as leaking storage tanks, and non-point sources, such as recharge of precipitation and stormwater runoff.

  19. TREATMENT OF HAZARDOUS LANDFILL LEACHATES AND CONTAMINATED GROUNDWATER

    EPA Science Inventory

    The objectives of the Cooperative Agreement were to assess the actual application of separate or combined biological and physical/chemical treatment techniques to high-strength hazardous dumpsite or landfill leachates, extractable wastes and spills, or sludges. our types of real-...

  20. Ground-water monitoring at Santa Barbara, California; Phase 3, development of a three-dimensional digital ground-water flow model for storage unit I of the Santa Barbara ground-water basin

    USGS Publications Warehouse

    Martin, Peter; Berenbrock, Charles

    1986-01-01

    Water-bearing rocks within the 7 sq mi of Storage Unit I of the Santa Barbara Groundwater Basin, consist of unconsolidated deposits that range in thickness from < 300 ft along the north perimeter of the unit to > 1,000 ft near the Pacific Ocean. The groundwater system was simulated as two horizontal layers separated by a confining bed. The model boundaries coincide with mapped faults on all sides. The faults were considered no-flow boundaries except for the offshore fault that forms the south boundary. This boundary was simulated as a general-head boundary , which allows water to move into and out of the modeled area. The model was calibrated by simulating both steady-state conditions (approximated by July 1978 and February 1983 water levels) and transient-state conditions (represented by May 1978 through December 1979 water level changes). The calibrated model was then used to simulate the period from January 1980 through December 1983 in order to verify the model. Model results generally closely matched measured data throughout Storage Unit I. During the transient and verification simulations, 9,980 acre-ft of groundwater was pumped from Storage Unit I for municipal use. Results of the model indicate that 42% (4,190 acre-ft) of the water pumped from the system was withdrawn from storage, 33% (3,290 acre-ft) was derived from changes in underflow across the offshore fault, and 25% (2,500 acre-ft) was derived from decreased groundwater discharge to drains. The model simulated that municipal pumpage induced about 1,380 acre-ft of water to move across the offshore fault toward Storage Unit I. Several model simulations were used to estimate aquifer response to different municipal pumpage patterns that could be used as management alternatives. Results of the simulations indicate that spreading municipal pumpage more evenly throughout Storage Unit I, by increasing the number of wells while reducing the pumping rate at the individual wells to maintain the same total

  1. Third party effects of groundwater law in the United States: Private versus common property

    SciTech Connect

    Bruggink, T.H. )

    1992-01-01

    Groundwater is an increasingly important component in the nation's total water supply. Although groundwater is one of this nation's most abundant resources, falling water tables and contamination episodes have caused localized water shortages. This has led to news media accounts describing water supply as the nation's next natural resource crisis. The problem with groundwater supply can be attributed in part to the current system of incomplete property rights. This, in combination with the common pool characteristics of underground water and other third party effects, has resulted in technical and allocative inefficiency. Groundwater hydrology, common property, contamination, and other third party effects are examined in seeking the causes of the current water crisis.

  2. LONG-TERM GEOCHEMICAL BEHAVIOR OF A ZEROVALENT IRON PERMEABLE REACTIVE BARRIER FOR THE TREATMENT OF HEXAVALENT CHROMIUM IN GROUNDWATER

    EPA Science Inventory

    Passive, in-situ reactive barriers have proven to be viable, cost-effective systems for the remediation of Cr-contaminated groundwater at some sites. Permeable reactive barriers (PRBs) are installed in the flow-path of groundwater, most typically as vertical treatment walls. Re...

  3. Data validation report for the 100-FR-3 Operable Unit, third round groundwater samples

    SciTech Connect

    Ayres, J.M.

    1994-03-31

    Westinghouse-Hanford has requested that a minimum of 20% of the total number of Sample Delivery Groups be validated for the 100-FR-3 operable Unit Third Round Groundwater sampling investigation. Therefore, the data from the chemical analysis of 51 samples from this sampling event and their related quality assurance samples were reviewed and validated to verify that reported sample results were of sufficient quality to support decisions regarding remedial actions performed at this site. The report is broken down into sections for each chemical analysis and radiochemical analysis type. Each section addresses the data package completeness, holding time adherence, instrument calibration and tuning acceptability, blank results, accuracy, precision, system performance, as well as the compound identification and quantitation. In addition, each section has an overall assessment and summary for the data packages reviewed for the particular chemical/radiochemical analyses. Detailed backup information is provided to the reader by SDG No. and sample number. For each data package, a matrix of chemical analyses per sample number is presented, as well as data qualification summaries.

  4. Pesticides and volatile organic compounds in shallow urban groundwater of the United States

    USGS Publications Warehouse

    Kolpin, Dana W.; Squillace, Paul J.; Zogorski, John S.; Barbash, Jack E.

    1997-01-01

    The widespread use of pesticides and volatile organic compounds (VOCs) over the past half century has led to their detection in many hydrologic systems in the United States. However, few systematic investigations of occurrences have been carried out over multistate regions using a consistent study design. Nine urban studies of shallow groundwater have been conducted to date as part of the U.S. Geological Survey's National Water-Quality Assessment Program. Pesticide compounds were detected in 48.6% of the 208 urban wells sampled. Sixteen different pesticide compounds were detected in samples from these wells. Prometon was by far the most frequently detected pesticide compound, being found in 8 of the 9 urban studies. VOCs were detected in 53.4% of the 208 urban wells sampled, with 36 different VOC compounds being found. Measured VOC concentrations exceeded current U.S. Environmental Protection Agency drinking water regulations in 19 wells. Methyl tert-butyl ether (MTBE), a common fuel oxygenate, was the most frequently detected VOC for this study.

  5. 2010 Groundwater Monitoring Report Central Nevada Test Area, Corrective Action Unit 443

    SciTech Connect

    2011-02-01

    This report presents the 2010 groundwater monitoring results collected by the U.S. Department of Energy (DOE) Office of Legacy Management (LM) for the Central Nevada Test Area (CNTA) Subsurface Corrective Action Unit (CAU) 443. Responsibility for the environmental site restoration of CNTA was transferred from the DOE Office of Environmental Management to LM on October 1, 2006. The environmental restoration process and corrective action strategy for CAU 443 are conducted in accordance with the Federal Facility Agreement and Consent Order entered into by DOE, the U.S. Department of Defense, and the State of Nevada. The corrective action strategy for the site includes proof-of-concept monitoring in support of site closure. This report summarizes investigation activities associated with CAU 443 that were conducted at the site from December 2009 through December 2010. It also represents the second year of the enhanced monitoring network and the 5-year proof-of-concept monitoring period that is intended to validate the compliance boundary

  6. 2009 Groundwater Monitoring Report Central Nevada Test Area, Corrective Action Unit 443

    SciTech Connect

    2010-09-01

    This report presents the 2009 groundwater monitoring results collected by the U.S. Department of Energy (DOE) Office of Legacy Management (LM) for the Central Nevada Test Area (CNTA) Subsurface Corrective Action Unit (CAU) 443. Responsibility for the environmental site restoration of CNTA was transferred from the DOE Office of Environmental Management to LM on October 1, 2006. The environmental restoration process and corrective action strategy for CAU 443 are conducted in accordance with the Federal Facility Agreement and Consent Order entered into by DOE, the U.S. Department of Defense, and the State of Nevada. The corrective action strategy for the site includes proof-of-concept monitoring in support of site closure. This report summarizes investigation activities associated with CAU 443 that were conducted at the site from October 2008 through December 2009. It also represents the first year of the enhanced monitoring network and begins the new 5-year proof-of-concept monitoring period that is intended to validate the compliance boundary

  7. Design and testing of a process-based groundwater vulnerability assessment (P-GWAVA) system for predicting concentrations of agrichemicals in groundwater across the United States

    USGS Publications Warehouse

    Barbash, Jack E; Voss, Frank D.

    2016-01-01

    Efforts to assess the likelihood of groundwater contamination from surface-derived compounds have spanned more than three decades. Relatively few of these assessments, however, have involved the use of process-based simulations of contaminant transport and fate in the subsurface, or compared the predictions from such models with measured data—especially over regional to national scales. To address this need, a process-based groundwater vulnerability assessment (P-GWAVA) system was constructed to use transport-and-fate simulations to predict the concentration of any surface-derived compound at a specified depth in the vadose zone anywhere in the conterminous United States. The system was then used to simulate the concentrations of selected agrichemicals in the vadose zone beneath agricultural areas in multiple locations across the conterminous United States. The simulated concentrations were compared with measured concentrations of the compounds detected in shallow groundwater (that is, groundwater drawn from within a depth of 6.3 ± 0.5 meters [mean ± 95 percent confidence interval] below the water table) in more than 1,400 locations across the United States. The results from these comparisons were used to select the simulation approaches that led to the closest agreement between the simulated and the measured concentrations.The P-GWAVA system uses computer simulations that account for a broader range of the hydrologic, physical, biological and chemical phenomena known to control the transport and fate of solutes in the subsurface than has been accounted for by any other vulnerability assessment over regional to national scales. Such phenomena include preferential transport and the influences of temperature, soil properties, and depth on the partitioning, transport, and transformation of pesticides in the subsurface. Published methods and detailed soil property data are used to estimate a wide range of model input parameters for each site, including surface

  8. Groundwater-Quality Data in the Madera-Chowchilla Study Unit, 2008: Results from the California GAMA Program

    USGS Publications Warehouse

    Shelton, Jennifer L.; Fram, Miranda S.; Belitz, Kenneth

    2009-01-01

    Groundwater quality in the approximately 860-square-mile Madera-Chowchilla study unit (MADCHOW) was investigated in April and May 2008 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The study was designed to provide a spatially unbiased assessment of the quality of raw groundwater used for public water supplies within MADCHOW, and to facilitate statistically consistent comparisons of groundwater quality throughout California. Samples were collected from 35 wells in Madera, Merced, and Fresno Counties. Thirty of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study area (grid wells), and five more were selected to provide additional sampling density to aid in understanding processes affecting groundwater quality (flow-path wells). Detection summaries in the text and tables are given for grid wells only, to avoid over-representation of the water quality in areas adjacent to flow-path wells. Groundwater samples were analyzed for a large number of synthetic organic constituents (volatile organic compounds [VOCs], low-level 1,2-dibromo-3-chloropropane [DBCP] and 1,2-dibromoethane [EDB], pesticides and pesticide degradates, polar pesticides and metabolites, and pharmaceutical compounds), constituents of special interest (N-nitrosodimethylamine [NDMA], perchlorate, and low-level 1,2,3-trichloropropane [1,2,3-TCP]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), and radioactive constituents (uranium isotopes, and gross alpha and gross beta particle activities). Naturally occurring isotopes and geochemical tracers (stable isotopes of hydrogen

  9. Environmental Aspects of Two Volatile Organic Compound Groundwater Treatment Designs at the Rocky Flats Site - 13135

    SciTech Connect

    Michalski, Casey C.; DiSalvo, Rick; Boylan, John

    2013-07-01

    DOE's Rocky Flats Site in Colorado is a former nuclear weapons production facility that began operations in the early 1950's. Because of releases of hazardous substances to the environment, the federally owned property and adjacent offsite areas were placed on the CERCLA National Priorities List in 1989. The final remedy was selected in 2006. Engineered components of the remedy include four groundwater treatment systems that were installed before closure as CERCLA-accelerated actions. Two of the systems, the Mound Site Plume Treatment System and the East Trenches Plume Treatment System, remove low levels of volatile organic compounds using zero-valent iron media, thereby reducing the loading of volatile organic compounds in surface water resulting from the groundwater pathway. However, the zero-valent iron treatment does not reliably reduce all volatile organic compounds to consistently meet water quality goals. While adding additional zero-valent iron media capacity could improve volatile organic compound removal capability, installation of a solar powered air-stripper has proven an effective treatment optimization in further reducing volatile organic compound concentrations. A comparison of the air stripper to the alternative of adding additional zero-valent iron capacity to improve Mound Site Plume Treatment System and East Trenches Plume Treatment System treatment based on several key sustainable remediation aspects indicates the air stripper is also more 'environmentally friendly'. These key aspects include air pollutant emissions, water quality, waste management, transportation, and costs. (authors)

  10. Permeable sorptive walls for treatment of hydrophobic organic contaminant plumes in groundwater

    SciTech Connect

    Grathwohl, P.; Peschik, G.

    1997-12-31

    Highly hydrophobic contaminants are easily adsorbed from aqueous solutions. Since for many of these compounds sorption increases with increasing organic carbon content natural materials such as bituminous shales and coals may be used in permeable sorptive walls. This, however, only applies if sorption is at equilibrium, which may not always be the case in groundwater treatment using a funnel-and-gate system. In contrast to the natural solids, granular activated carbons (GACs) have very high sorption capacities and reasonably fast sorption kinetics. The laboratory results show that application of GACs (e.g. F100) is economically feasible for in situ removal of polycyclic aromatic hydrocarbons (PAH) from groundwater at a former manufactured gas plant site (MGP). For less sorbing compounds (such as benzene, toluene, xylenes) a combination of adsorption and biodegradation is necessary (i.e. sorptive + reactive treatment).

  11. Implications of projected climate change for groundwater recharge in the western United States

    NASA Astrophysics Data System (ADS)

    Meixner, Thomas; Manning, Andrew H.; Stonestrom, David A.; Allen, Diana M.; Ajami, Hoori; Blasch, Kyle W.; Brookfield, Andrea E.; Castro, Christopher L.; Clark, Jordan F.; Gochis, David J.; Flint, Alan L.; Neff, Kirstin L.; Niraula, Rewati; Rodell, Matthew; Scanlon, Bridget R.; Singha, Kamini; Walvoord, Michelle A.

    2016-03-01

    Existing studies on the impacts of climate change on groundwater recharge are either global or basin/location-specific. The global studies lack the specificity to inform decision making, while the local studies do little to clarify potential changes over large regions (major river basins, states, or groups of states), a scale often important in the development of water policy. An analysis of the potential impact of climate change on groundwater recharge across the western United States (west of 100° longitude) is presented synthesizing existing studies and applying current knowledge of recharge processes and amounts. Eight representative aquifers located across the region were evaluated. For each aquifer published recharge budget components were converted into four standard recharge mechanisms: diffuse, focused, irrigation, and mountain-systems recharge. Future changes in individual recharge mechanisms and total recharge were then estimated for each aquifer. Model-based studies of projected climate-change effects on recharge were available and utilized for half of the aquifers. For the remainder, forecasted changes in temperature and precipitation were logically propagated through each recharge mechanism producing qualitative estimates of direction of changes in recharge only (not magnitude). Several key patterns emerge from the analysis. First, the available estimates indicate average declines of 10-20% in total recharge across the southern aquifers, but with a wide range of uncertainty that includes no change. Second, the northern set of aquifers will likely incur little change to slight increases in total recharge. Third, mountain system recharge is expected to decline across much of the region due to decreased snowpack, with that impact lessening with higher elevation and latitude. Factors contributing the greatest uncertainty in the estimates include: (1) limited studies quantitatively coupling climate projections to recharge estimation methods using detailed

  12. Groundwater-quality data in the Klamath Mountains study unit, 2010: results from the California GAMA Program

    USGS Publications Warehouse

    Mathany, Timothy M.; Belitz, Kenneth

    2014-01-01

    Groundwater quality in the 8,806-square-mile Klamath Mountains (KLAM) study unit was investigated by the U.S. Geological Survey (USGS) from October to December 2010, as part of the California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and Assessment (GAMA) Program’s Priority Basin Project (PBP). The GAMA-PBP was developed in response to the California Groundwater Quality Monitoring Act of 2001 and is being conducted in collaboration with the SWRCB and Lawrence Livermore National Laboratory (LLNL). The KLAM study unit was the thirty-third study unit to be sampled as part of the GAMA-PBP. The GAMA Klamath Mountains study was designed to provide a spatially unbiased assessment of untreated-groundwater quality in the primary aquifer system and to facilitate statistically consistent comparisons of untreated-groundwater quality throughout California. The primary aquifer system is defined by the perforation intervals of wells listed in the California Department of Public Health (CDPH) database for the KLAM study unit. Groundwater quality in the primary aquifer system may differ from the quality in the shallower or deeper water-bearing zones; shallower groundwater may be more vulnerable to surficial contamination. In the KLAM study unit, groundwater samples were collected from sites in Del Norte, Siskiyou, Humboldt, Trinity, Tehama, and Shasta Counties, California. Of the 39 sites sampled, 38 were selected by using a spatially distributed, randomized grid-based method to provide statistical representation of the primary aquifer system in the study unit (grid sites), and the remaining site was non-randomized (understanding site). The groundwater samples were analyzed for basic field parameters, organic constituents (volatile organic compounds [VOCs] and pesticides and pesticide degradates), inorganic constituents (trace elements, nutrients, major and minor ions, total dissolved solids [TDS]), radon-222, gross alpha and gross beta

  13. Groundwater-Quality Data in the Colorado River Study Unit, 2007: Results from the California GAMA Program

    USGS Publications Warehouse

    Goldrath, Dara A.; Wright, Michael T.; Belitz, Kenneth

    2010-01-01

    Groundwater quality in the 188-square-mile Colorado River Study unit (COLOR) was investigated October through December 2007 as part of the Priority Basin Project of the California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001, and the U.S. Geological Survey (USGS) is the technical project lead. The Colorado River study was designed to provide a spatially unbiased assessment of the quality of raw groundwater used for public water supplies within COLOR, and to facilitate statistically consistent comparisons of groundwater quality throughout California. Samples were collected from 28 wells in three study areas in San Bernardino, Riverside, and Imperial Counties. Twenty wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the Study unit; these wells are termed 'grid wells'. Eight additional wells were selected to evaluate specific water-quality issues in the study area; these wells are termed `understanding wells.' The groundwater samples were analyzed for organic constituents (volatile organic compounds [VOC], gasoline oxygenates and degradates, pesticides and pesticide degradates, pharmaceutical compounds), constituents of special interest (perchlorate, 1,4-dioxane, and 1,2,3-trichlorpropane [1,2,3-TCP]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), and radioactive constituents. Concentrations of naturally occurring isotopes (tritium, carbon-14, and stable isotopes of hydrogen and oxygen in water), and dissolved noble gases also were measured to help identify the sources and ages of the sampled groundwater. In total, approximately 220 constituents and water-quality indicators were investigated. Quality-control samples (blanks, replicates, and matrix spikes) were collected at

  14. Treatment - mother-infant inpatient units.

    PubMed

    Glangeaud-Freudenthal, Nine M C; Howard, Louise M; Sutter-Dallay, Anne-Laure

    2014-01-01

    Infants of parents with psychiatric disorders may be particularly vulnerable and have a higher risk of developing psychiatric disorders in adulthood. Until the second half of the 20th century, women and infants were cared for separately. Today, hospitalisation of women with their babies in psychiatric mother-baby units enables psychiatric care of women and promotion of parent-infant interactions and child development. The distribution of psychiatric mother-baby units around the world, as well as within countries, varies strongly. Reasons for this may be related to the absence of national perinatal mental health policies related to psychiatric mother-baby unit location, differences in sources of referral for admission, and criteria for psychiatric mother-baby unit admission. Two principal national epidemiologic studies, in England and in France and Belgium, have described issues related to discharge from such care, as have smaller local studies, but no epidemiologic studies have yet demonstrated that joint inpatient psychiatric mother-baby unit care is cost-effective compared with separate care. PMID:24054169

  15. Relationship between altitude and lithium in groundwater in the United States of America: results of a 1992–2003 study

    PubMed Central

    Huber, Rebekah S.; Kim, Namkug; Renshaw, Carl E.; Renshaw, Perry F.; Kondo, Douglas G.

    2015-01-01

    Therapeutic dosages of lithium are known to reduce suicide rates, which has led to investigations of confounding environmental risk factors for suicide such as lithium in groundwater. It has been speculated that this might play a role in the potential relationship between suicide and altitude. A recent study in Austria involving geospatial analysis of lithium in groundwater and suicide found lower levels of lithium at higher altitudes. Since there is no reason to suspect this correlation is universal given variation in geology, the current study set out to investigate the relationship between altitude and lithium in groundwater in the United States of America (USA). The study utilised data extracted from the National Water-Quality Assessment programme implemented by the United States Geological Survey that has collected 5,183 samples from 48 study areas in USA for the period of 1992 to 2003. Lithium was the trace-element of interest and 518 samples were used in the current analyses. Due to uneven lithium sampling within the country, only the states (n=15) with the highest number of lithium samples were included. Federal information processing standard codes were used to match data by county with the mean county altitude calculated using altitude data from the Shuttle Radar Topography Mission. The study was controlled for potential confounding factors known to affect levels of lithium in groundwater including aquifer, aquifer type, lithology, water level and the depths of wells. The levels of lithium in groundwater, increased with altitude (R2 = 0.226, P <0.001) during the study period. These findings differ from the Austrian study and suggest a need for further research accounting also for the impact of geographical variation. PMID:25545940

  16. Relationship between altitude and lithium in groundwater in the United States of America: results of a 1992-2003 study.

    PubMed

    Huber, Rebekah S; Kim, Namkug; Renshaw, Carl E; Renshaw, Perry F; Kondo, Douglas G

    2014-11-01

    Therapeutic dosages of lithium are known to reduce suicide rates, which has led to investigations of confounding environmental risk factors for suicide such as lithium in groundwater. It has been speculated that this might play a role in the potential relationship between suicide and altitude. A recent study in Austria involving geospatial analysis of lithium in groundwater and suicide found lower levels of lithium at higher altitudes. Since there is no reason to suspect this correlation is universal given variation in geology, the current study set out to investigate the relationship between altitude and lithium in groundwater in the United States of America (USA). The study utilised data extracted from the National Water-Quality Assessment programme implemented by the United States Geological Survey that has collected 5,183 samples from 48 study areas in USA for the period of 1992 to 2003. Lithium was the trace-element of interest and 518 samples were used in the current analyses. Due to uneven lithium sampling within the country, only the states (n=15) with the highest number of lithium samples were included. Federal information processing standard codes were used to match data by county with the mean county altitude calculated using altitude data from the Shuttle Radar Topography Mission. The study was controlled for potential confounding factors known to affect levels of lithium in groundwater including aquifer, aquifer type, lithology, water level and the depths of wells. The levels of lithium in groundwater, increased with altitude (R(2) = 0.226, P <0.001) during the study period. These findings differ from the Austrian study and suggest a need for further research accounting also for the impact of geographical variation. PMID:25545940

  17. Groundwater-quality data in the Cascade Range and Modoc Plateau study unit, 2010-Results from the California GAMA Program

    USGS Publications Warehouse

    Shelton, Jennifer L.; Fram, Miranda S.; Belitz, Kenneth

    2013-01-01

    Groundwater quality in the 39,000-square-kilometer Cascade Range and Modoc Plateau (CAMP) study unit was investigated by the U.S. Geological Survey (USGS) from July through October 2010, as part of the California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and Assessment (GAMA) Program’s Priority Basin Project (PBP). The GAMA PBP was developed in response to the California Groundwater Quality Monitoring Act of 2001 and is being conducted in collaboration with the SWRCB and Lawrence Livermore National Laboratory (LLNL). The CAMP study unit is the thirty-second study unit to be sampled as part of the GAMA PBP. The GAMA CAMP study was designed to provide a spatially unbiased assessment of untreated-groundwater quality in the primary aquifer system and to facilitate statistically consistent comparisons of untreated-groundwater quality throughout California. The primary aquifer system is defined as that part of the aquifer corresponding to the open or screened intervals of wells listed in the California Department of Public Health (CDPH) database for the CAMP study unit. The quality of groundwater in shallow or deep water-bearing zones may differ from the quality of groundwater in the primary aquifer system; shallow groundwater may be more vulnerable to surficial contamination. In the CAMP study unit, groundwater samples were collected from 90 wells and springs in 6 study areas (Sacramento Valley Eastside, Honey Lake Valley, Cascade Range and Modoc Plateau Low Use Basins, Shasta Valley and Mount Shasta Volcanic Area, Quaternary Volcanic Areas, and Tertiary Volcanic Areas) in Butte, Lassen, Modoc, Plumas, Shasta, Siskiyou, and Tehama Counties. Wells and springs were selected by using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells). Groundwater samples were analyzed for field water-quality indicators, organic constituents, perchlorate, inorganic constituents

  18. Stroke management and the impact of mobile stroke treatment units.

    PubMed

    Rasmussen, Peter A

    2015-12-01

    Stroke remains the fifth leading cause of death in the United States, despite declining morbidity and mortality rates. Patients who receive timely care provided by mobile stroke treatment unit staffs have dramatically improved outcomes compared with patients who receive initial treatment in an emergency department. Portable imaging technology and wireless communication devices have contributed significantly to shorter time to treatment, which is a key factor in improved outcomes. PMID:26694888

  19. Transport of Nitrogen and Phosphorus from Onsite Wastewater Treatment Systems to Shallow Groundwater

    NASA Astrophysics Data System (ADS)

    Toor, G.

    2014-12-01

    The knowledge about the nutrients transport from the vadose zone of onsite wastewater treatment systems (commonly called septic systems) is crucial to protect groundwater quality as 25% of US population uses septic systems to discharge household wastewater. For example, our preliminary data showed that about 47% of applied water was recovered at 60-cm below drainfield of septic systems. This implies that contaminants present in wastewater, if not attenuated in the vadose zone, can be transported to shallow groundwater. This presentation will focus on the biophysical and hydrologic controls on the transport of nitrogen (N) and phosphorus (P) from the vadose of two conventional (drip dispersal, gravel trench) and an advanced (with aerobic and anaerobic medias) system. These systems were constructed using two rows of drip pipe (37 emitters/mound) placed 0.3 m apart in the center of 6 m x 0.6 m drainfield. Each system received 120 L of wastewater per day. During 20-month period (May 2012 to December 2013), soil-water samples were collected from the vadose zone using suction cup lysimeters installed at 0.30, 0.60, and 1.05 m depth and groundwater samples were collected from piezometers installed at 3-3.30 m depth below the drainfield. A complimentary 1-year study using smaller drainfields (0.5 m long, 0.9 m wide, 0.9 m high) was conducted to obtain better insights in the vadose zone. A variety of instruments (multi-probe sensors, suction cup lysimeters, piezometers, tensiometers) were installed in the vadose zones. Results showed that nitrification controlled N evolution in drainfield and subsequent transport of N plumes (>10 mg/L) into groundwater. Most of the wastewater applied soluble inorganic P (>10 mg/L) was quickly attenuated in the drainfield due to fixation (sorption, precipitation) in the vadose zone (<0.10 mg/L), which was further reduced to <0.05 mg/L in groundwater. The hydrologic controls (primarily rainfall during June-September) facilitated transport of

  20. Hydrologic Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nye County, Nevada, Revision 0

    SciTech Connect

    Drici, Warda

    2004-02-01

    This report documents the analysis of the available hydrologic data conducted in support of the development of a Corrective Action Unit (CAU) groundwater flow model for Central and Western Pahute Mesa: CAUs 101 and 102.

  1. Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nye County, Nevada, Revision 0

    SciTech Connect

    Drici, Warda

    2003-08-01

    This report documents the analysis of the available transport parameter data conducted in support of the development of a Corrective Action Unit (CAU) groundwater flow model for Central and Western Pahute Mesa: CAUs 101 and 102.

  2. A comparison of recharge rates in aquifers of the United States based on groundwater-age data

    NASA Astrophysics Data System (ADS)

    McMahon, P. B.; Plummer, L. N.; Böhlke, J. K.; Shapiro, S. D.; Hinkle, S. R.

    2011-06-01

    An overview is presented of existing groundwater-age data and their implications for assessing rates and timescales of recharge in selected unconfined aquifer systems of the United States. Apparent age distributions in aquifers determined from chlorofluorocarbon, sulfur hexafluoride, tritium/helium-3, and radiocarbon measurements from 565 wells in 45 networks were used to calculate groundwater recharge rates. Timescales of recharge were defined by 1,873 distributed tritium measurements and 102 radiocarbon measurements from 27 well networks. Recharge rates ranged from < 10 to 1,200 mm/yr in selected aquifers on the basis of measured vertical age distributions and assuming exponential age gradients. On a regional basis, recharge rates based on tracers of young groundwater exhibited a significant inverse correlation with mean annual air temperature and a significant positive correlation with mean annual precipitation. Comparison of recharge derived from groundwater ages with recharge derived from stream base-flow evaluation showed similar overall patterns but substantial local differences. Results from this compilation demonstrate that age-based recharge estimates can provide useful insights into spatial and temporal variability in recharge at a national scale and factors controlling that variability. Local age-based recharge estimates provide empirical data and process information that are needed for testing and improving more spatially complete model-based methods.

  3. A comparison of recharge rates in aquifers of the United States based on groundwater-age data

    USGS Publications Warehouse

    McMahon, P.B.; Plummer, L.N.; Böhlke, J.K.; Shapiro, S.D.; Hinkle, S.R.

    2011-01-01

    An overview is presented of existing groundwater-age data and their implications for assessing rates and timescales of recharge in selected unconfined aquifer systems of the United States. Apparent age distributions in aquifers determined from chlorofluorocarbon, sulfur hexafluoride, tritium/helium-3, and radiocarbon measurements from 565 wells in 45 networks were used to calculate groundwater recharge rates. Timescales of recharge were defined by 1,873 distributed tritium measurements and 102 radiocarbon measurements from 27 well networks. Recharge rates ranged from < 10 to 1,200 mm/yr in selected aquifers on the basis of measured vertical age distributions and assuming exponential age gradients. On a regional basis, recharge rates based on tracers of young groundwater exhibited a significant inverse correlation with mean annual air temperature and a significant positive correlation with mean annual precipitation. Comparison of recharge derived from groundwater ages with recharge derived from stream base-flow evaluation showed similar overall patterns but substantial local differences. Results from this compilation demonstrate that age-based recharge estimates can provide useful insights into spatial and temporal variability in recharge at a national scale and factors controlling that variability. Local age-based recharge estimates provide empirical data and process information that are needed for testing and improving more spatially complete model-based methods.

  4. Groundwater-Quality Data in the Antelope Valley Study Unit, 2008: Results from the California GAMA Program

    USGS Publications Warehouse

    Schmitt, Stephen J.; Milby Dawson, Barbara J.; Belitz, Kenneth

    2009-01-01

    Groundwater quality in the approximately 1,600 square-mile Antelope Valley study unit (ANT) was investigated from January to April 2008 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The study was designed to provide a spatially unbiased assessment of the quality of raw groundwater used for public water supplies within ANT, and to facilitate statistically consistent comparisons of groundwater quality throughout California. Samples were collected from 57 wells in Kern, Los Angeles, and San Bernardino Counties. Fifty-six of the wells were selected using a spatially distributed, randomized, grid-based method to provide statistical representation of the study area (grid wells), and one additional well was selected to aid in evaluation of specific water-quality issues (understanding well). The groundwater samples were analyzed for a large number of organic constituents (volatile organic compounds [VOCs], gasoline additives and degradates, pesticides and pesticide degradates, fumigants, and pharmaceutical compounds), constituents of special interest (perchlorate, N-nitrosodimethylamine [NDMA], and 1,2,3-trichloropropane [1,2,3-TCP]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), and radioactive constituents (gross alpha and gross beta radioactivity, radium isotopes, and radon-222). Naturally occurring isotopes (strontium, tritium, and carbon-14, and stable isotopes of hydrogen and oxygen in water), and dissolved noble gases also were measured to help identify the sources and ages of the sampled groundwater. In total, 239 constituents and water-quality indicators (field parameters) were investigated. Quality

  5. A new separation and treatment method for soil and groundwater restoration

    SciTech Connect

    Hitchens, G.D.

    1997-10-01

    Soil and groundwater contamination by organic compounds is a widespread environmental pollution problem. In many cases, contaminated soil is excavated and transported to a landfill or is incinerated to remove contaminants. These remediation practices are expensive, environmentally disruptive, require extensive permitting, and only move contamination from one location to another. Onsite and in situ treatment techniques offer a safer, more cost-effective, and permanent solution. Many soil and groundwater contaminants are highly volatile, enabling the use of methods such as in situ vacuum extraction and air injection for their removal. However, these methods are often difficult to use because of slow volatilization rates and the lack of effective methods to treat the extracted hazardous material. This Phase I Small Business Innovation Research program focuses on developing an in situ soil and groundwater remediation technique that is effective against volatile as well as nonvolatile compounds and that will shorten treatment times. The technique forms the basis of a new catalytic process to degrade extracted contaminants onsite. Key hardware elements on which the new technique is based have been proven in preliminary research. The method has a high potential for public and regulatory acceptance because of its low environment impact.

  6. Is managed care closing substance abuse treatment units?

    PubMed

    Wells, Rebecca; Harris Lemak, Christy; Alexander, Jeffrey A; Roddy, Brian L; Nahra, Tammie A

    2007-03-01

    Despite high levels of unmet need for outpatient substance abuse treatment, a significant percentage of outpatient units have closed over the past several years. This study drew on 1999-2000 and 2005 national surveys to determine if managed care was associated with outpatient substance abuse treatment units' likelihood of surviving. Each substance abuse unit director was asked about the presence of any managed care contracts, percentage revenues from managed care, percentage of clients for whom prior authorization was required, and percentage of clients for whom concurrent review was required. A multiple logistic regression revealed that none of these factors was associated with substance abuse treatment unit survival. At this point, neither the presence nor the structure of managed care appears to affect the survival of outpatient substance abuse treatment units. Given the need for these facilities, however, and their vulnerability to closure, continued attention to managed care's potential influence is warranted. PMID:17458479

  7. Task 21 - Evaluation of Artificial Freeze Crystallization and Natural Freeze-Thaw Processes for the Treatment of Contaminated Groundwater at the Strachan Gas Plant in Alberta, Canada - Sour Gas Remediation Technology R{ampersand}D

    SciTech Connect

    1997-03-01

    During the period from 1993 to 1996, a long-term program was initiated to conduct remediation research at the Strachan Gas Plant in Alberta, Canada. As part of this research program, optimization of the existing pump-and-treat (P{ampersand}T) facility was of interest. The cost-effective treatment of contaminated groundwater produced from the P{ampersand}T system was complicated by several factors, including: (1) increased cost and reduced effectiveness of most water treatment processes because of the cold temperatures and severe winter conditions prevalent in Alberta, (2) interference caused by the mixture of inorganic and organic contaminants found in the groundwater that can reduce the effectiveness of many water treatment processes, and (3) pretreatment to prevent scaling in existing treatment process unit operations caused by the iron, manganese, and hardness of the contaminated groundwater.

  8. [Study on the advanced pre-treatments of reclaimed water used for groundwater recharge].

    PubMed

    Gao, Yu-Tuan; Zhang, Xue; Zhao, Xuan; Zhao, Gang

    2012-03-01

    To prevent groundwater contamination, pretreatments of reclaimed water are needed before the groundwater recharge. In this study, five treatments, including ultrafiltration (UF), ozonation, magnetic ion exchange (MIEX), UF coupled with ozonation and MIEX coupled with ozonation, were evaluated for their purification efficiencies of the reclaimed water and their influences on the following soil aquifer treatments. For organic matters in the secondary effluents, identified as dissolved organic carbon (DOC) and specific ultraviolet absorbance (SUVA), 20% DOC and 10% SUVA are removed by MIEX treatment with dose of 5 mL x L(-1), while only 10% DOC and no SUVA are removed by UF, but neither of these two pretreatments enhance the purification of soil aquifer treatments. Differently, SUVA of the secondary effluents are removed by 60%-79% by ozonation alone or coupled with UF/MIEX, increasing the biodegradability of the reclaimed water. These pretreatments significantly enhance the removal of organic matters by the following soil aquifer with DOC in the final effluents reducing to 1-2 mg x L(-1). For nitrogen, MIEX can remove 25% NO3(-) -N, and ozonation can remove 72% NH4(+) -N. The soil aquifer treatment could efficiently remove NH4(+) -N to below 0.5 mg x L(-1), while no obvious removal is detected for NO3(-) -N. In conclusion, more attentions should be paid to the organic matters and NO3(-) -N during the pretreatments of reclaimed water. Among all the pretreatments tested here, ozonation coupled with MIEX is capable of increasing the biodegradability of the reclaimed water and removing NO3(-) -N, which is a good choice for the pretreatment of groundwater recharge. PMID:22624368

  9. Ground-Water Quality Data in the Coachella Valley Study Unit, 2007: Results from the California GAMA Program

    USGS Publications Warehouse

    Goldrath, Dara A.; Wright, Michael T.; Belitz, Kenneth

    2009-01-01

    Ground-water quality in the approximately 820 square-mile Coachella Valley Study Unit (COA) was investigated during February and March 2007 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The study was designed to provide a spatially unbiased assessment of raw ground water used for public-water supplies within the Coachella Valley, and to facilitate statistically consistent comparisons of ground-water quality throughout California. Samples were collected from 35 wells in Riverside County. Nineteen of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells). Sixteen additional wells were sampled to evaluate changes in water chemistry along selected ground-water flow paths, examine land use effects on ground-water quality, and to collect water-quality data in areas where little exists. These wells were referred to as 'understanding wells'. The ground-water samples were analyzed for a large number of organic constituents (volatile organic compounds [VOC], pesticides and pesticide degradates, pharmaceutical compounds, and potential wastewater-indicator compounds), constituents of special interest (perchlorate and 1,2,3-trichloropropane [1,2,3-TCP]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial indicators. Naturally occurring isotopes (uranium, tritium, carbon-14, and stable isotopes of hydrogen, oxygen, and boron), and dissolved noble gases (the last in collaboration with Lawrence Livermore National Laboratory) also were measured to help identify the source and age of the sampled

  10. Groundwater-quality data in the Western San Joaquin Valley study unit, 2010 - Results from the California GAMA Program

    USGS Publications Warehouse

    Mathany, Timothy M.; Landon, Matthew K.; Shelton, Jennifer L.; Belitz, Kenneth

    2013-01-01

    Groundwater quality in the approximately 2,170-square-mile Western San Joaquin Valley (WSJV) study unit was investigated by the U.S. Geological Survey (USGS) from March to July 2010, as part of the California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and Assessment (GAMA) Program's Priority Basin Project (PBP). The GAMA-PBP was developed in response to the California Groundwater Quality Monitoring Act of 2001 and is being conducted in collaboration with the SWRCB and Lawrence Livermore National Laboratory (LLNL). The WSJV study unit was the twenty-ninth study unit to be sampled as part of the GAMA-PBP. The GAMA Western San Joaquin Valley study was designed to provide a spatially unbiased assessment of untreated-groundwater quality in the primary aquifer system, and to facilitate statistically consistent comparisons of untreated groundwater quality throughout California. The primary aquifer system is defined as parts of aquifers corresponding to the perforation intervals of wells listed in the California Department of Public Health (CDPH) database for the WSJV study unit. Groundwater quality in the primary aquifer system may differ from the quality in the shallower or deeper water-bearing zones; shallow groundwater may be more vulnerable to surficial contamination. In the WSJV study unit, groundwater samples were collected from 58 wells in 2 study areas (Delta-Mendota subbasin and Westside subbasin) in Stanislaus, Merced, Madera, Fresno, and Kings Counties. Thirty-nine of the wells were selected by using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells), and 19 wells were selected to aid in the understanding of aquifer-system flow and related groundwater-quality issues (understanding wells). The groundwater samples were analyzed for organic constituents (volatile organic compounds [VOCs], low-level fumigants, and pesticides and pesticide degradates

  11. Regression models for estimating concentrations of atrazine plus deethylatrazine in shallow groundwater in agricultural areas of the United States.

    PubMed

    Stackelberg, Paul E; Barbash, Jack E; Gilliom, Robert J; Stone, Wesley W; Wolock, David M

    2012-01-01

    Tobit regression models were developed to predict the summed concentration of atrazine [6-chloro--ethyl--(1-methylethyl)-1,3,5-triazine-2,4-diamine] and its degradate deethylatrazine [6-chloro--(1-methylethyl)-1,3,5,-triazine-2,4-diamine] (DEA) in shallow groundwater underlying agricultural settings across the conterminous United States. The models were developed from atrazine and DEA concentrations in samples from 1298 wells and explanatory variables that represent the source of atrazine and various aspects of the transport and fate of atrazine and DEA in the subsurface. One advantage of these newly developed models over previous national regression models is that they predict concentrations (rather than detection frequency), which can be compared with water quality benchmarks. Model results indicate that variability in the concentration of atrazine residues (atrazine plus DEA) in groundwater underlying agricultural areas is more strongly controlled by the history of atrazine use in relation to the timing of recharge (groundwater age) than by processes that control the dispersion, adsorption, or degradation of these compounds in the saturated zone. Current (1990s) atrazine use was found to be a weak explanatory variable, perhaps because it does not represent the use of atrazine at the time of recharge of the sampled groundwater and because the likelihood that these compounds will reach the water table is affected by other factors operating within the unsaturated zone, such as soil characteristics, artificial drainage, and water movement. Results show that only about 5% of agricultural areas have greater than a 10% probability of exceeding the USEPA maximum contaminant level of 3.0 μg L. These models are not developed for regulatory purposes but rather can be used to (i) identify areas of potential concern, (ii) provide conservative estimates of the concentrations of atrazine residues in deeper potential drinking water supplies, and (iii) set priorities among

  12. Regression models for estimating concentrations of atrazine plus deethylatrazine in shallow groundwater in agricultural areas of the United States

    USGS Publications Warehouse

    Stackelberg, Paul E.; Barbash, Jack E.; Gilliom, Robert J.; Stone, Wesley W.; Wolock, David M.

    2012-01-01

    Tobit regression models were developed to predict the summed concentration of atrazine [6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine] and its degradate deethylatrazine [6-chloro-N-(1-methylethyl)-1,3,5,-triazine-2,4-diamine] (DEA) in shallow groundwater underlying agricultural settings across the conterminous United States. The models were developed from atrazine and DEA concentrations in samples from 1298 wells and explanatory variables that represent the source of atrazine and various aspects of the transport and fate of atrazine and DEA in the subsurface. One advantage of these newly developed models over previous national regression models is that they predict concentrations (rather than detection frequency), which can be compared with water quality benchmarks. Model results indicate that variability in the concentration of atrazine residues (atrazine plus DEA) in groundwater underlying agricultural areas is more strongly controlled by the history of atrazine use in relation to the timing of recharge (groundwater age) than by processes that control the dispersion, adsorption, or degradation of these compounds in the saturated zone. Current (1990s) atrazine use was found to be a weak explanatory variable, perhaps because it does not represent the use of atrazine at the time of recharge of the sampled groundwater and because the likelihood that these compounds will reach the water table is affected by other factors operating within the unsaturated zone, such as soil characteristics, artificial drainage, and water movement. Results show that only about 5% of agricultural areas have greater than a 10% probability of exceeding the USEPA maximum contaminant level of 3.0 μg L-1. These models are not developed for regulatory purposes but rather can be used to (i) identify areas of potential concern, (ii) provide conservative estimates of the concentrations of atrazine residues in deeper potential drinking water supplies, and (iii) set priorities

  13. Enhanced zero-valent metal permeable wall treatment of contaminated groundwater

    SciTech Connect

    Reinhart, D.R.; Clausen, C.A.; Geiger, C.

    1997-12-31

    On-going research at the University of Central Florida, supported by NASA, is investigating the use of sonicated zero-valent metal permeable treatment walls to remediate chlorinated solvent contaminated groundwater. Use of ultrasound within the treatment wall is proposed to enhance and/or restore the activity of the zero-valent metal. Batch studies designed to evaluate the destruction of chlorinated hydrocarbons using enhanced zero-valent metal reduction found a nearly three-fold increase in reaction rates after ultrasound treatment. Column studies substantiated these results. It is hypothesized that ultrasound serves to remove corrosion products from the iron surface and will prolong the reactive life and efficiency of the permeable treatment wall, thus decreasing long-term costs of wall construction and maintenance.

  14. Installation of a subsurface groundwater treatment wall composed of granular zero-valent iron

    SciTech Connect

    Yamane, C.L.; Warner, S.D.; Gallinatti, J.D.

    1995-12-01

    A subsurface treatment wan (consisting of granular, zero-valent iron and gravel) and low-permeability slurry wall system was installed as the final remedy at a former semiconductor manufacturing facility in the south San Francisco Bay area. The property has been vacant since 1983, and the former facility`s lease recently expired. This treatment wall replaced a groundwater pump and treat system that was installed as an interim remedy in 1987. While the pump and treat system may have been acceptable to regulatory agencies as a final site remedy, the treatment wall was proposed and eventually selected as the final remedy because it would eliminate above-ground treatment systems on the property and thereby have little to no effect on the property`s future use; it would eliminate the necessity for weekly operation and maintenance and therefore avoid access issues that might arise after the tenant`s lease expired; and it would greatly reduce total remediation costs.

  15. Ground-water resources of the Ainsworth unit, Cherry and Brown Counties, Nebraska

    USGS Publications Warehouse

    Cronin, James G.; Newport, Thomas G.; Krieger, R.A.

    1956-01-01

    mantles the deposits of Pleistocene age in about 80 percent of the Ainsworth unit and a thin deposit of loess covers the surface elsewhere. Terrace deposits border the flood plain of the principal streams, and alluvium underlies the flood plain of most of the stream valleys in the area. Precipitation and underflow from the southwest are the principal sources of the ground water in the Ainsworth unit. As most of the precipitation in the sandhills evaporates, is utilized by growing plants, or penetrates to the zone of saturation, the overland runoff from this part of the area is small. In the vicinity of Ainsworth a minor amount of recharge probably is derived from the return of irrigation water pumped from wells. Where the water table is near the surface in the valleys of the sandhills, ground water is discharged directly from the zone of saturation to the atmosphere by evapotranspiration; and, as the surface of the lakes in the sandhills area is an extension of the water table, evaporation from the lake surface also constitutes ground-water discharge. In addition, ground water is discharged by the streams that are incised below the water table and by subsurface outflow. The yield of wells accounts for only a small part of the discharge of ground water from the area. In the Ainsworth unit the water table slopes northeastward from the region of favorable recharge, the sandhills, toward the Niobrara River and its principal tributaries. The average gradient of the water table is about 10 feet per mile. In the sandhills the water table is at or near the surface in the valleys and as much as 100 feet, or a little more, beneath the higher sandhills. In the vicinity of Ainsworth the water level in wells ranges from less than 1 foot to about 40 feet below the land surface, but nearer the Niobrara River and close to its deeply entrenched tributaries the depth to the water table is as much as, or a little more than, 200 feet. The coefficient of transmissibility of the gr

  16. Occurrence of pesticides in shallow groundwater of the United States: initial results from the National Water-Quality Assessment program

    USGS Publications Warehouse

    Kolpin, Dana W.; Barbash, Jack E.; Gilliom, Robert J.

    1998-01-01

    The first phase of intensive data collection for the National Water-Quality Assessment (NAWQA) was completed during 1993−1995 in 20 major hydrologic basins of the United States. Groundwater land-use studies, designed to sample recently recharged groundwater (generally within 10 years) beneath specific land-use and hydrogeologic settings, are a major component of the groundwater quality as sessment for NAWQA. Pesticide results from the 41 land-use studies conducted during 1993−1995 indicate that pesticides were commonly detected in shallow groundwater, having been found at 54.4% of the 1034 sites sampled in agricultural and urban settings across the United States. Pesticide concentrations were generally low, with over 95% of the detections at concentrations less than 1 μg/L. Of the 46 pesticide compounds examined, 39 were detected. The compounds detected most frequently were atrazine (38.2%), deethylatrazine (34.2%), simazine (18.0%), metolachlor (14.6%), and prometon (13.9%). Statistically significant relations were observed between frequencies of detection and the use, mobility, and persistence of these compounds. Pesticides were commonly detected in both agricultural (56.4%; 813 sites) and urban (46.6%; 221 sites) settings. Frequent detections of pesticides in urban areas indicate that, as is the case with agricultural pesticide use in agricultural areas, urban and suburban pesticide use significantly contribute to pesticide occurrence in shallow groundwater. Although pesticides were detected in groundwater sampled in urban areas and all nine of the agricultural land-use categories examined, significant variations in occurrence were observed among these categories. Maximum contaminant levels (MCLs) established by the U.S. Environmental Protection Agency for drinking water were exceeded for only one pesticide (atrazine, 3 μg/L) at a single location. However, MCLs have been established for only 25 of the 46 pesticide compounds examined, do not cover pesticide

  17. Groundwater vulnerability assessment in the vicinity of Ramtha wastewater treatment plant, North Jordan

    NASA Astrophysics Data System (ADS)

    Awawdeh, Muheeb; Obeidat, Mutewekil; Zaiter, Ghusun

    2015-12-01

    The main aim of this study was to evaluate the vulnerability of groundwater to contamination in the vicinity of Ramtha wastewater treatment plant using a modified DRASTIC method in a GIS environment. A groundwater pollution potential map was prepared using modified DRASTIC method by adding lineaments and land use/land cover parameters. The values of the modified DRASTIC index were classified into three categories: low, moderate and high. About 36.5 % of the study area is occupied by the high vulnerability class, 56.5 % is occupied by the moderate vulnerability class and 9 % is occupied by the low vulnerability class. Chemical analysis of the water samples collected from wells distributed in the study area and tapping Umm Rijam aquifer indicated that the nitrate concentration ranges from 20 to 193 mg/L with an average 65.5 mg/L. Nitrate exceeded the permissible limits of WHO and Jordanian standards in 69 and 54 % of the NO3 - samples, respectively. The modified DRASTIC model was validated using nitrate concentration. Results showed a good match between nitrate concentrations level and the groundwater vulnerability classes.

  18. Groundwater and stream E. coli concentrations in coastal plain watersheds served by onsite wastewater and a municipal sewer treatment system.

    PubMed

    Humphrey, Charles; Finley, Algernon; O'Driscoll, Michael; Manda, Alex; Iverson, Guy

    2015-01-01

    The goal of this study was to determine if onsite wastewater treatment systems (OWS) were influencing groundwater and surface water Escherichia coli concentrations in a coastal plain watershed. Piezometers for groundwater monitoring were installed at four residences served by OWS and five residences served by a municipal wastewater treatment system (MWS). The residences were located in two different, but nearby (<3 km), watersheds. Effluent from the four septic tanks, groundwater from piezometers, and the streams draining the OWS and MWS watersheds were sampled on five dates between September 2011 and May 2012. Groundwater E. coli concentrations and specific conductivity were elevated within the flow path of the OWS and near the stream, relative to other groundwater sampling locations in the two watersheds. Groundwater discharge in the OWS watershed could be a contributor of E. coli to the stream because E. coli concentrations in groundwater at the stream bank and in the stream were similar. Stream E. coli concentrations were higher for the OWS in relation to MWS watersheds on each sampling date. Water quality could be improved by ensuring OWS are installed and operated to maintain adequate separation distances to water resources. PMID:26540548

  19. Ground-Water Quality Data in the Coastal Los Angeles Basin Study Unit, 2006: Results from the California GAMA Program

    USGS Publications Warehouse

    Mathany, Timothy M.; Land, Michael; Belitz, Kenneth

    2008-01-01

    Ground-water quality in the approximately 860 square-mile Coastal Los Angeles Basin study unit (CLAB) was investigated from June to November of 2006 as part of the Statewide Basin Assessment Project of the Ground-Water Ambient Monitoring and Assessment (GAMA) Program. The GAMA Statewide Basin Assessment was developed in response to the Ground-Water Quality Monitoring Act of 2001, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The Coastal Los Angeles Basin study was designed to provide a spatially unbiased assessment of raw ground-water quality within CLAB, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 69 wells in Los Angeles and Orange Counties. Fifty-five of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study area (?grid wells?). Fourteen additional wells were selected to evaluate changes in ground-water chemistry or to gain a greater understanding of the ground-water quality within a specific portion of the Coastal Los Angeles Basin study unit ('understanding wells'). Ground-water samples were analyzed for: a large number of synthetic organic constituents [volatile organic compounds (VOCs), gasoline oxygenates and their degradates, pesticides, polar pesticides, and pesticide degradates, pharmaceutical compounds, and potential wastewater-indicators]; constituents of special interest [perchlorate, N-nitrosodimethylamine (NDMA), 1,4-dioxane, and 1,2,3-trichloropropane (1,2,3-TCP)]; inorganic constituents that can occur naturally [nutrients, major and minor ions, and trace elements]; radioactive constituents [gross-alpha and gross-beta radiation, radium isotopes, and radon-222]; and microbial indicators. Naturally occurring isotopes [stable isotopic ratios of hydrogen and oxygen, and activities of tritium and carbon-14

  20. Ground-Water Quality Data in the Kern County Subbasin Study Unit, 2006 - Results from the California GAMA Program

    USGS Publications Warehouse

    Shelton, Jennifer L.; Pimentel, Isabel; Fram, Miranda S.; Belitz, Kenneth

    2008-01-01

    Ground-water quality in the approximately 3,000 square-mile Kern County Subbasin study unit (KERN) was investigated from January to March, 2006, as part of the Priority Basin Assessment Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Assessment project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by the California State Water Resources Control Board (SWRCB) in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory (LLNL). The Kern County Subbasin study was designed to provide a spatially unbiased assessment of raw (untreated) ground-water quality within KERN, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 50 wells within the San Joaquin Valley portion of Kern County. Forty-seven of the wells were selected using a randomized grid-based method to provide a statistical representation of the ground-water resources within the study unit. Three additional wells were sampled to aid in the evaluation of changes in water chemistry along regional ground-water flow paths. The ground-water samples were analyzed for a large number of man-made organic constituents (volatile organic compounds [VOCs], pesticides, and pesticide degradates), constituents of special interest (perchlorate, N-nitrosodimethylamine [NDMA], and 1,2,3-trichloropropane [1,2,3-TCP]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial indicators. Naturally occurring isotopes (tritium, carbon-14, and stable isotopes of hydrogen, oxygen, nitrogen, and carbon) and dissolved noble gases also were measured to help identify the source and age of the sampled ground water. Quality-control samples (blanks, replicates, and laboratory matrix spikes) were collected and analyzed at approximately 10 percent of

  1. Groundwater bills

    NASA Astrophysics Data System (ADS)

    U.S. lawmakers have become concerned about groundwater problems in the United States, and thus the contamination of groundwater is rapidly becoming one of the hottest issues of 1987 and probably for many years into the future. The 100th Congress has seen a proliferation of bills relating to various problems involving groundwater: need for more data, funding of research, and development of standards for groundwater quality. Because round 50% of the nation's drinking water is obtained from groundwater, the available support is dependent not only upon the available quantity but also on the quality of that supply.Because groundwater quality in general and groundwater contamination in particular provides such complex problems, final legislation probably will emphasize more research and more data collection. At present, a bill, the National Ground Water Contamination Research Act, has been introduced in the House of Representatives by Rep. Sam Gejdenson (D-Conn.), and a companion bill has been introduced in the Senate by Sen. David Durenberger (R-Minn.). These bills renew action on a groundwater research bill that passed the House but not the Senate near the end of the 99th Congress. The bills address not only research but also promote a national program for the assessment of groundwater quality and a national clearinghouse for groundwater information.

  2. Evaluation of recharge in selected aquifer systems of the United States using tracers of groundwater age (Invited)

    NASA Astrophysics Data System (ADS)

    McMahon, P. B.; Plummer, L. N.; Bohlke, J. K.; Shapiro, S. D.; Hinkle, S. R.

    2009-12-01

    Well constrained water budgets are needed to assess groundwater availability and manage aquifers sustainably throughout the world. Recharge is perhaps the most difficult water-budget component to quantify because of its spatial and temporal variability and because it is difficult to measure directly. Understanding of recharge could be improved through an analysis of groundwater age data because groundwater age distributions integrate recharge processes at relatively large spatial and temporal scales and can be direct measures of recharge. In this presentation, we synthesize existing datasets of groundwater age into a consistent analysis of the timescales and rates of recharge at a national scale. Timescales of recharge, as defined by 2,746 distributed tritium measurements and 224 radiocarbon measurements from 18 flow path studies, varied widely across the United States and were dependent on factors such as aquifer confinement, climate, geologic features like karst conduits and fractures, and changes in sea level. On average, 78 % of sampled flow path lengths in confined aquifers contained pre-Holocene recharge compared to 23 % in unconfined aquifers. Age distributions in aquifers determined from 650 sulfur hexafluoride, chlorofluorocarbon, and tritium/helium-3 measurements from 25 flow path studies and 27 water-table well networks were used to calculate recharge rates for young (0-50 year) groundwater. Recharge rates of young groundwater ranged from 34 to 1,200 mm/year and were dependent on factors such as climate, geology, land use, and topography. Recharge was inversely related to air temperature for a group of 10 flow path studies receiving similar precipitation from South Carolina to Massachusetts, presumably because of the diminishing effects of evapotranspiration on recharge with decreasing temperature. Recharge was directly related to precipitation for a group of 13 flow path studies having similar air temperatures from Massachusetts to Oregon. Regional

  3. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Estimated Mean Annual Natural Groundwater Recharge, 2002

    USGS Publications Warehouse

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the mean annual natural groundwater recharge, in millimeters, compiled for every catchment of NHDPlus for the conterminous United States. The source data set is Estimated Mean Annual Natural Ground-Water Recharge in the Conterminous United States (Wolock, 2003). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, containing NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins, contains NHDPlus Production Units 4, 5, 7 and 9. MRB4, covering the

  4. Evaluation of Zeolite Permeable Treatment Wall for the Removal of Strontium-90 from Groundwater

    NASA Astrophysics Data System (ADS)

    Seneca, S. M.; Bandilla, K.; Rabideau, A. J.; Ross, E.; Bronner, C. E.

    2009-12-01

    Experimental and modeling studies are in progress to evaluate the potential performance of a permeable treatment wall comprised of zeolite-rich rock for the removal of strontium-90 from groundwater. Column studies were performed using a synthetic groundwater referenced to anticipate field conditions, with a focus on quantifying the competitive ion exchange among five cations (Na+, K+, Ca2+, Mg2+, and Sr2+). Ongoing studies are focused on the comparison of zeolites obtained from two sources: Teague Mineral Products (Adrian, OR) and Bear River Zeolite (Preston, UT), and on the possible influence of native soil that is mixed with treatment wall material during construction. The data obtained from the column studies is used to support robust estimation of zeolite cation exchange parameters producing a five-solute cation exchange model describing the removal efficiency of the zeolite. The field-scale transport model provides flexibility to explore design parameters to support the possible deployment of a full scale treatment wall at a Western New York nuclear facility.

  5. Pilot scale evaluation of peroxone for treatment of contaminated groundwater. Technical report

    SciTech Connect

    Zappi, M.; Swindle, R.; Harvey, S.; Morgan, R.; Strang, D.

    1994-12-31

    Advance oxidation processes (AOPs) are treatment processes that rely on the hydroxyl radical to destroy contaminants in polluted waters. Peroxone is an advanced oxidation process that utilizes the reaction of ozone and hydrogen peroxide to produce hydroxyl radicals without the requirement of ultraviolet light. The USAE Waterways Experiment Station (WES) evaluated the use of peroxone at Rocky Mountain Arsenal (RMA) for treatment of groundwater contaminated with diisopropylmethylphosphonate (DIMP) and low levels of pesticides. This evaluation was performed at RMA using a pilot scale treatment system. Results indicate that DIMP was easily oxidized to below detection limit levels. Optimization of the process indicated that a 250 m1/1 hydrogen peroxide dose in four columns plumbed in series that were all sparged with 2.2% ozonated air at a rate of 2.5 scfm.

  6. Status and understanding of groundwater quality in the Klamath Mountains study unit, 2010: California GAMA Priority Basin Project

    USGS Publications Warehouse

    Bennett, George Luther, V; Fram, Miranda S.; Belitz, Kenneth

    2014-01-01

    Groundwater quality in the Klamath Mountains (KLAM) study unit was investigated as part of the Priority Basin Project of the California Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is located in Del Norte, Humboldt, Shasta, Siskiyou, Tehama, and Trinity Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The GAMA Priority Basin Project was designed to provide a spatially unbiased, statistically robust assessment of the quality of untreated (raw) groundwater in the primary aquifer system. The assessment is based on water-quality data and explanatory factors for groundwater samples collected in 2010 by the USGS from 39 sites and on water-quality data from the California Department of Public Health (CDPH) water-quality database. The primary aquifer system was defined by the depth intervals of the wells listed in the CDPH water-quality database for the KLAM study unit. The quality of groundwater in the primary aquifer system may be different from that in the shallower or deeper water-bearing zones; shallow groundwater may be more vulnerable to surficial contamination. This study included two types of assessments: (1) a status assessment, which characterized the status of the current quality of the groundwater resource by using data from samples analyzed for volatile organic compounds, pesticides, and naturally occurring inorganic constituents, such as major ions and trace elements, and (2) an understanding assessment, which evaluated the natural and human factors potentially affecting the groundwater quality. The assessments were intended to characterize the quality of groundwater resources in the primary aquifer system of the KLAM study unit, not the quality of treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentrations

  7. Remedial investigation work plan for the Groundwater Operable Unit at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    SciTech Connect

    Not Available

    1994-03-01

    This Remedial Investigation (RI) Work Plan has been developed as part of the US Department of Energy`s (DOE`s) investigation of the Groundwater Operable Unit (GWOU) at Oak Ridge National Laboratory (ORNL) located near Oak Ridge, Tennessee. The first iteration of the GWOU RI Work Plan is intended to serve as a strategy document to guide the ORNL GWOU RI. The Work Plan provides a rationale and organization for groundwater data acquisition, monitoring, and remedial actions to be performed during implementation of environmental restoration activities associated with the ORNL GWOU. It Is important to note that the RI Work Plan for the ORNL GWOU is not a prototypical work plan. The RI will be conducted using annual work plans to manage the work activities, and task reports will be used to document the results of the investigations. Sampling and analysis results will be compiled and reported annually with a review of data relative to risk (screening level risk assessment review) for groundwater. This Work Plan outlines the overall strategy for the RI and defines tasks which are to be conducted during the initial phase of investigation. This plan is presented with the understanding that more specific addenda to the plan will follow.

  8. Assessing the impacts of future demand for saline groundwater on commercial deployment of CCS in the United States

    SciTech Connect

    Davidson, Casie L.; Dooley, James J.; Dahowski, Robert T.

    2009-04-20

    This paper provides a preliminary assessment of the potential impact that future demand for groundwater might have on the commercial deployment of carbon dioxide capture and storage (CCS) technologies within the United States. A number of regions within the U.S. have populations, agriculture and industries that are particularly dependent upon groundwater. Moreover, some key freshwater aquifers are already over-utilized or depleted, and others are likely to be moving toward depletion as demand grows. The need to meet future water demands may lead some parts of the nation to consider supplementing existing supplies with lower quality groundwater resources, including brackish waters that are currently not considered sources of drinking water but which could provide supplemental water via desalination. In some areas, these same deep saline-filled geologic formations also represent possible candidate carbon dioxide (CO2) storage reservoirs. The analysis presented here suggests that future constraints on CCS deployment due to potential needs to supplement conventional water supplies by desalinating deeper and more brackish waters are likely to be necessary only in limited regions across the country, particularly in areas that are already experiencing water stress.

  9. Review: Regional groundwater flow modeling in heavily irrigated basins of selected states in the western United States

    NASA Astrophysics Data System (ADS)

    Rossman, Nathan R.; Zlotnik, Vitaly A.

    2013-09-01

    Water resources in agriculture-dominated basins of the arid western United States are stressed due to long-term impacts from pumping. A review of 88 regional groundwater-flow modeling applications from seven intensively irrigated western states (Arizona, California, Colorado, Idaho, Kansas, Nebraska and Texas) was conducted to provide hydrogeologists, modelers, water managers, and decision makers insight about past modeling studies that will aid future model development. Groundwater models were classified into three types: resource evaluation models (39 %), which quantify water budgets and act as preliminary models intended to be updated later, or constitute re-calibrations of older models; management/planning models (55 %), used to explore and identify management plans based on the response of the groundwater system to water-development or climate scenarios, sometimes under water-use constraints; and water rights models (7 %), used to make water administration decisions based on model output and to quantify water shortages incurred by water users or climate changes. Results for 27 model characteristics are summarized by state and model type, and important comparisons and contrasts are highlighted. Consideration of modeling uncertainty and the management focus toward sustainability, adaptive management and resilience are discussed, and future modeling recommendations, in light of the reviewed models and other published works, are presented.

  10. COST ESTIMATION MODELS FOR DRINKING WATER TREATMENT UNIT PROCESSES

    EPA Science Inventory

    Cost models for unit processes typically utilized in a conventional water treatment plant and in package treatment plant technology are compiled in this paper. The cost curves are represented as a function of specified design parameters and are categorized into four major catego...

  11. Statement of Work for Drilling Five CERCLA Groundwater Monitoring Wells During Fiscal Year 2006, 300-FF-5 Operable Unit

    SciTech Connect

    Williams, Bruce A.

    2005-08-01

    Pacific Northwest National Laboratory, the U.S. Department of Energy (DOE), and the regulators have agreed that two characterization wells along with three additional performance monitoring wells shall be installed in the 300-FF-5 Operable Unit as defined in the proposed Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement [TPA]) Milestone M-24-57 and the 300-FF-5 Limited Field Investigation plan (DOE/RL-2005-47). This document contains the statement of work required to drill, characterize, and construct the proposed groundwater monitoring wells during FY 2006.

  12. Vulnerability of recently recharged groundwater in principal aquifers of the United States to nitrate contamination

    USGS Publications Warehouse

    Gurdak, Jason J.; Qi, Sharon L.

    2012-01-01

    Recently recharged water (defined here as <60 years old) is generally the most vulnerable part of a groundwater resource to nonpoint-source nitrate contamination. Understanding at the appropriate scale the interactions of natural and anthropogenic controlling factors that influence nitrate occurrence in recently recharged groundwater is critical to support best management and policy decisions that are often made at the aquifer to subaquifer scale. New logistic regression models were developed using data from the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) program and National Water Information System for 17 principal aquifers of the U.S. to identify important source, transport, and attenuation factors that control nonpoint source nitrate concentrations greater than relative background levels in recently recharged groundwater and were used to predict the probability of detecting elevated nitrate in areas beyond the sampling network. Results indicate that dissolved oxygen, crops and irrigated cropland, fertilizer application, seasonally high water table, and soil properties that affect infiltration and denitrification are among the most important factors in predicting elevated nitrate concentrations. Important differences in controlling factors and spatial predictions were identified in the principal aquifer and national-scale models and support the conclusion that similar spatial scales are needed between informed groundwater management and model development.

  13. Investigation of Ground-Water Contamination at Solid Waste Management Unit 12, Naval Weapons Station Charleston, North Charleston, South Carolina

    USGS Publications Warehouse

    Vroblesky, Don A.; Casey, Clifton C.; Petkewich, Matthew D.; Lowery, Mark A.; Conlon, Kevin J.; Harrelson, Larry G.

    2007-01-01

    The U.S. Geological Survey and the Naval Facilities Engineering Command Southeast investigated natural and engineered remediation of chlorinated volatile organic compound ground-water contamination at Solid Waste Management Unit 12 at the Naval Weapons Station Charleston, North Charleston, South Carolina. The primary contaminants of interest are tetrachloroethene, 1,1,1-trichloroethane, trichloroethene, cis-1,2-dichloroethene, vinyl chloride, 1,1-dichloroethane, and 1,1-dichloroethene. In general, the hydrogeology of Solid Waste Management Unit 12 consists of a surficial aquifer, composed of sand to clayey sand, overlain by dense clay that extends from about land surface to a depth of about 8 to 10 feet and substantially limits local recharge. During some months in the summer, evapotranspiration and limited local recharge result in ground-water level depressions in the forested area near wells 12MW-12S and 12MW-17S, seasonally reflecting the effects of evapotranspiration. Changes in surface-water levels following Hurricane Gaston in 2004 resulted in a substantial change in the ground-water levels at the site that, in turn, may have caused lateral shifting of the contaminant plume. Hydraulic conductivity, determined by slug tests, is higher along the axis of the plume in the downgradient part of the forests than adjacent to the plume, implying that there is some degree of lithologic control on the plume location. Hydraulic conductivity, hydraulic gradient, sulfur-hexafluoride measurements, and historical data indicate that ground-water flow rates are substantially slower in the forested area relative to upgradient areas. The ground-water contamination, consisting of chlorinated volatile organic compounds, extends eastward in the surficial aquifer from the probable source area near a former underground storage tank. Engineered remediation approaches include a permeable reactive barrier and phytoremediation. The central part of the permeable reactive barrier along the

  14. Status and understanding of groundwater quality in the Madera, Chowchilla Study Unit, 2008: California GAMA Priority Basin Project

    USGS Publications Warehouse

    Shelton, Jennifer L.; Fram, Miranda S.; Belitz, Kenneth; Jurgens, Bryant C.

    2013-01-01

    Groundwater quality in the approximately 860-square-mile Madera and Chowchilla Subbasins (Madera-Chowchilla study unit) of the San Joaquin Valley Basin was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is located in California's Central Valley region in parts of Madera, Merced, and Fresno Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The Project was designed to provide statistically robust assessments of untreated groundwater quality within the primary aquifer systems in California. The primary aquifer system within each study unit is defined by the depth of the perforated or open intervals of the wells listed in the California Department of Public Health (CDPH) database of wells used for municipal and community drinking-water supply. The quality of groundwater in shallower or deeper water-bearing zones may differ from that in the primary aquifer system; shallower groundwater may be more vulnerable to contamination from the surface. The assessments for the Madera-Chowchilla study unit were based on water-quality and ancillary data collected by the USGS from 35 wells during April-May 2008 and water-quality data reported in the CDPH database. Two types of assessments were made: (1) status, assessment of the current quality of the groundwater resource, and (2) understanding, identification of natural factors and human activities affecting groundwater quality. The primary aquifer system is represented by the grid wells, of which 90 percent (%) had depths that ranged from about 200 to 800 feet (ft) below land surface and had depths to the top of perforations that ranged from about 140 to 400 ft below land surface. Relative-concentrations (sample concentrations divided by benchmark concentrations) were used for

  15. Microbial fuel cells as pollutant treatment units: Research updates.

    PubMed

    Zhang, Quanguo; Hu, Jianjun; Lee, Duu-Jong

    2016-10-01

    Microbial fuel cells (MFC) are a device that can convert chemical energy in influent substances to electricity via biological pathways. Based on the consent that MFC technology should be applied as a waste/wastewater treatment unit rather than a renewable energy source, this mini-review discussed recent R&D efforts on MFC technologies for pollutant treatments and highlighted the challenges and research and development needs. Owing to the low power density levels achievable by larger-scale MFC, the MFC should be used as a device other than energy source such as being a pollutant treatment unit. PMID:26906446

  16. Groundwater geochemical and selected volatile organic compound data, Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington, July 2013

    USGS Publications Warehouse

    Huffman, Raegan L.

    2014-01-01

    Previous investigations indicate that concentrations of chlorinated volatile organic compounds (CVOCs) are substantial in groundwater beneath the 9-acre former landfill at Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington. The U.S. Geological Survey has continued to monitor groundwater geochemistry to ensure that conditions remain favorable for contaminant biodegradation as specified in the Record of Decision for the site. This report presents groundwater geochemical and selected CVOC data collected at Operable Unit 1 by the U.S. Geological Survey during July 9–18, 2013, in support of longterm monitoring for natural attenuation. Groundwater samples were collected from 13 wells and 9 piezometers, as well as from 10 shallow groundwater passive-diffusion sampling sites in the nearby marsh. Samples from all wells and piezometers were analyzed for oxidation-reduction (redox) sensitive constituents and dissolved gases. Samples from all piezometers and four wells also were analyzed for CVOCs, as were all samples from the passive-diffusion sampling sites. In 2013, concentrations of redox-sensitive constituents measured at all wells and piezometers were consistent with those measured in previous years, with dissolved oxygen concentrations at all except an upgradient well 0.2 milligrams per liter or less; little to no detectable nitrate; abundant dissolved manganese, iron, and methane; and commonly detected sulfide. In the upper aquifer of the northern plantation in 2013, CVOC concentrations at all piezometers were similar to those measured in previous years, and concentrations of the reductive dechlorination byproducts ethane and ethene were slightly lower or the same as concentrations measured in 2012. In the upper aquifer of the southern plantation, CVOC concentrations measured in piezometers during 2013 continued to be variable as in previous years, and often very high, and reductive dechlorination byproducts were detected in two of the three

  17. Investigation of Contaminated Groundwater at Solid Waste Management Unit 12, Naval Weapons Station Charleston, North Charleston, South Carolina, 2008

    USGS Publications Warehouse

    Vroblesky, Don A.; Petkewich, Matthew D.

    2009-01-01

    The U.S. Geological Survey and the Naval Facilities Engineering Command Southeast investigated natural and engineered remediation of chlorinated volatile organic compound (VOC) groundwater contamination at Solid Waste Management Unit 12 at the Naval Weapons Station Charleston, North Charleston, South Carolina, beginning in 2000. The primary contaminants of interest in the study are tetrachloroethene, 1,1,1-trichloroethane, trichloroethene, cis-1,2-dichloroethene, vinyl chloride, 1,1-dichloroethane, and 1,1-dichloroethene. Engineered remediation aspects at the site consist of a zero-valent-iron permeable reactive barrier (PRB) installed in December 2002 intercepting the contamination plume and a phytoremediation test stand of loblolly pine trees planted in the source area in May 2003. The U.S. Geological Survey planted an additional phytoremediation test stand of loblolly pine trees on the upgradient side of the southern end of the PRB in February 2008. At least once during the summer, however, the trees were inadvertently mowed during lawn cutting activity. The PRB along the main axis of the contaminant plume appears to be actively removing contamination. In contrast to the central area of the PRB, the data from the southern end of the PRB indicate that contaminants are moving around the PRB. Concentrations in wells upgradient from the PRB showed a general decrease in VOC concentrations. VOC concentrations in some wells in the forest downgradient from the PRB showed a sharp increase in 2005, followed by a decrease in 2006. Farther downgradient in the forest, the VOC concentrations began to increase in 2007 and continued to increase into 2008. The VOC-concentration changes in groundwater beneath the forest appear to indicate movement of a groundwater-contaminant pulse through the forest. It also is possible that the data may represent lateral shifting of the plume in response to changes in groundwater-flow direction.

  18. Tritium monitoring in groundwater and evaluation of model predictions for the Hanford Site 200 Area Effluent Treatment Facility

    SciTech Connect

    Barnett, D.B.; Bergeron, M.P.; Cole, C.R.; Freshley, M.D.; Wurstner, S.K.

    1997-08-01

    The Effluent Treatment Facility (ETF) disposal site, also known as the State-Approved Land Disposal Site (SALDS), receives treated effluent containing tritium, which is allowed to infiltrate through the soil column to the water table. Tritium was first detected in groundwater monitoring wells around the facility in July 1996. The SALDS groundwater monitoring plan requires revision of a predictive groundwater model and reevaluation of the monitoring well network one year from the first detection of tritium in groundwater. This document is written primarily to satisfy these requirements and to report on analytical results for tritium in the SALDS groundwater monitoring network through April 1997. The document also recommends an approach to continued groundwater monitoring for tritium at the SALDS. Comparison of numerical groundwater models applied over the last several years indicate that earlier predictions, which show tritium from the SALDS approaching the Columbia River, were too simplified or overly robust in source assumptions. The most recent modeling indicates that concentrations of tritium above 500 pCi/L will extend, at most, no further than {approximately}1.5 km from the facility, using the most reasonable projections of ETF operation. This extent encompasses only the wells in the current SALDS tritium-tracking network.

  19. Evaluation of a UV/Ozone Treatment Process for Removal of MTBE in Groundwater Supplies in New Mexico

    EPA Science Inventory

    EPA’s Office of Research and Development is funding pilot-scale studies on MTBE contaminated groundwater using UV/ozone treatment technology (254 nm UV, 5.8 mg/L ozone). The pilot-scale treatment system consists of a GW well pump, a feed tank, a pretreatment system (water softene...

  20. Evaluation of a UV/Ozone Treatment Process for Removal of MTBE in Groundwater Supplies in New Mexico

    EPA Science Inventory

    EPA’s Office of Research and Development is funding pilot-scale studies on MTBE contaminated groundwater using UV/ozone treatment technology (254 nm UV, 5.8 mg/L ozone). The pilot-scale treatment system consists of a GW well pump, a feed tank, a pretreatment system (water soften...

  1. Complexed iron removal from groundwater

    SciTech Connect

    Munter, R.; Ojaste, H.; Sutt, J.

    2005-07-01

    The paper demonstrates an intensive work carried out and results obtained on the pilot plant of the City of Kogalym Water Treatment Station (Tjumen, Siberia, Russian Federation) to elaborate on a contemporary nonreagent treatment technology for the local iron-rich groundwater. Several filter materials (Birm, Pyrolox, hydroanthracite, Everzit, granulated activated carbon) and chemical oxidants (ozone, chlorine, hydrogen peroxide, oxygen, and potassium permanganate) were tested to solve the problem with complexed iron removal from groundwater. The final elaborated technology consists of raw water intensive aeration in the gas-degas treatment unit followed by sequential filtration through hydroanthracite and the special anthracite Everzit.

  2. Arsenic in ground-water under oxidizing conditions, south-west United States.

    PubMed

    Robertson, F N

    1989-12-01

    Concentrations of dissolved arsenic in ground-water in alluvial basins of Arizona commonly exceed 50 μg L(-1) and reach values as large as 1,300 μg L(-1). Arsenic speciation analyses show that arsenic occurs in the fully oxidized state of plus 5 (As+5), most likely in the form of HAsO4(∼2), under existing oxidizing and pH conditions. Arsenic in source areas presumably is oxidized to soluble As before transport into the basin or, if after transport, before burial. Probable sources of arsenic are the sulphide and arsenide deposits in the mineralized areas of the mountains surrounding the basins. Arsenic content of alluvial material ranged from 2 to 88 ppm. Occurrence and removal of arsenic in ground-water are related to the pH and the redox condition of the ground-water, the oxidation state of arsenic, and sorption or exchange. Within basins, dissolved arsenic correlates (P<0.01) with dissolved molybdenum, selenium, vanadium, and fluoride and with pH, suggesting sorption of negative ions. The sorption hypothesis is further supported by enrichment of teachable arsenic in the basin-fill sediments by about tenfold relative to the crustal abundance and by as much as a thousandfold relative to concentrations found in ground-water. Silicate hydrolysis reactions, as defined within the alluvial basins, under closed conditions cause increases in pH basinward and would promote desorption. Within the region, large concentrations of arsenic are commonly associated with the central parts of basins whose chemistries evolve under closed conditions. Arsenic does not correlate with dissolved iron (r = 0.09) but may be partly controlled by iron in the solid phase. High solid-phase arsenic contents were found in red clay beds. Large concentrations of arsenic also were found in water associated with red clay beds. Basins that contain the larger concentrations are bounded primarily by basalt and andesite, suggesting that the iron content as well as the arsenic content of the basin

  3. Arsenic in ground-water under oxidizing conditions, south-west United States

    USGS Publications Warehouse

    Robertson, F.N.

    1989-01-01

    Concentrations of dissolved arsenic in ground-water in alluvial basins of Arizona commonly exceed 50 ??g L-1 and reach values as large as 1,300 ??g L-1. Arsenic speciation analyses show that arsenic occurs in the fully oxidized state of plus 5 (As+5), most likely in the form of HAsO4???2, under existing oxidizing and pH conditions. Arsenic in source areas presumably is oxidized to soluble As before transport into the basin or, if after transport, before burial. Probable sources of arsenic are the sulphide and arsenide deposits in the mineralized areas of the mountains surrounding the basins. Arsenic content of alluvial material ranged from 2 to 88 ppm. Occurrence and removal of arsenic in ground-water are related to the pH and the redox condition of the ground-water, the oxidation state of arsenic, and sorption or exchange. Within basins, dissolved arsenic correlates (P<0.01) with dissolved molybdenum, selenium, vanadium, and fluoride and with pH, suggesting sorption of negative ions. The sorption hypothesis is further supported by enrichment of teachable arsenic in the basin-fill sediments by about tenfold relative to the crustal abundance and by as much as a thousandfold relative to concentrations found in ground-water. Silicate hydrolysis reactions, as defined within the alluvial basins, under closed conditions cause increases in pH basinward and would promote desorption. Within the region, large concentrations of arsenic are commonly associated with the central parts of basins whose chemistries evolve under closed conditions. Arsenic does not correlate with dissolved iron (r = 0.09) but may be partly controlled by iron in the solid phase. High solid-phase arsenic contents were found in red clay beds. Large concentrations of arsenic also were found in water associated with red clay beds. Basins that contain the larger concentrations are bounded primarily by basalt and andesite, suggesting that the iron content as well as the arsenic content of the basin fill may

  4. Regional ground-water mixing and the origin of saline fluids: Midcontinent, United States

    SciTech Connect

    Musgrove, M.; Banner, J.L. )

    1993-03-26

    Ground waters in three adjacent regional flow systems in the midcontinent exhibit extreme chemical and isotopic variations that delineate large-scale fluid flow and mixing processes and two distinct mechanisms for the generation of saline fluids. Systematic spatial variations of major ion concentrations, H, O, and Sr isotopic compositions, and ground-water migration pathways indicate that each flow system contains water of markedly different origin. Mixing of the three separate ground waters exerts a fundamental control on ground-water composition. The three ground waters are: (i) dilute meteoric water recharged in southern Missouri; (ii) saline Na-Ca-Cl water in southeastern Kansas of far-traveled meteoric origin that acquired its salinity by halite dissolution; and (iii) Na-Ca-Cl brines in north-central Oklahoma that may have originated as Paleozoic seawater. 45 refs., 4 figs., 1 tab.

  5. Leaching of plutonium from a radioactive waste glass by eight groundwaters from the western United States

    USGS Publications Warehouse

    Rees, T.F.; Cleveland, J.M.; Nash, K.L.

    1985-01-01

    The leachability of a radioactive waste glass formulated to Battelle Pacific Northwest Laboratory specification 80-270 has been studied using eight actual groundwaters with a range of chemical compositions as leachants. Waters collected from the Grande Ronde Basalt (Washington State) and from alluvial deposits in the Hualapai Valley (Arizona) were the most effective at removing plutonium from this glass. Leaching was shown to be incongruent; plutonium was removed from the glass more slowly than the overall glass matrix. The results of these experiments indicate the need to study the leachability of actual waste forms using the actual projected groundwaters that are most likely to come into contact with the waste should a radioactive waste repository be breached.

  6. Examining Mechanisms of Groundwater Hg(II) Treatment by Reactive Materials: An EXAFS Study

    SciTech Connect

    Gibson, Blair D.; Ptacek, Carol J.; Lindsay, Matthew B.J.; Blowes, David W.

    2012-02-07

    Laboratory batch experiments were conducted to examine mechanisms of Hg(II) removal by reactive materials proposed for groundwater treatment. These materials included granular iron filings (GIF), 1:1 (w/w) mixtures of metallurgical granular Fe powder + elemental S (MGI+S) and elemental Cu + elemental S (Cu+S), granular activated carbon (GAC), attapulgite clay (ATP), ATP treated with 2-amino-5-thiol-1,3,4-thiadiazole (ATP-a), and ATP treated with 2,5-dimercapto-1,3,4-thiadiazole (ATP-d). Following treatment of simulated groundwater containing 4 mg L{sup -1} Hg for 8 or 16 days, the solution pH values ranged from 6.8 to 8.8 and Eh values ranged from +400 to -400 mV. Large decreases in aqueous Hg concentrations were observed for ATP-d (>99%), GIF (95%), MGI+S (94%), and Cu+S (90%). Treatment of Hg was less effective using ATP (29%), ATP-a (69%), and GAC (78%). Extended X-ray absorption fine structure (EXAFS) spectra of Hg on GIF, MGI+S, and GAC indicated the presence of an Hg-O bond at 2.04-2.07 {angstrom}, suggesting that Hg was bound to GIF corrosion products or to oxygen complexes associated with water sorbed to activated carbon. In contrast, bond lengths ranging from 2.35 to 2.48 {angstrom} were observed for Hg in Cu+S, ATP-a, and ATP-d treatments, suggesting the formation of Hg-S bonds.

  7. Shallow ground-water flow, water levels, and quality of water, 1980-84, Cowles Unit, Indiana Dunes National Lakeshore

    SciTech Connect

    Cohen, D.A.; Shedlock, R.J.

    1986-01-01

    The Cowles Unit of Indiana Dunes National Lakeshore in Porter County, northwest Indiana, contains a broad dune-beach complex along the southern shoreline of Lake Michigan and a large wetland, called the Great Marsh, that occupies the lowland between the shoreline dunes and an older dune-beach complex farther inland. Water levels and water quality in the surficial aquifer were monitored from 1977 to 1984 near settling ponds on adjacent industrial property at the western end of the Cowles Unit. Since 1980, when the settling pond bottoms were sealed, these intradunal lowlands contained standing water only during periods of high snowmelt or rainfall. Water level declines following the cessation of seepage ranged from 6 feet at the eastern-most settling pond to nearly 14 feet at the western-most pond. No general pattern of water table decline was observed in the Great Marsh or in the shoreline dune complex at distances > 3,000 ft east or north of the settling ponds. Since the settling ponds were sealed, the concentration of boron has decreased while concentrations of cadmium, arsenic, zinc, and molybdenum in shallow ground-water downgradient of the ponds show no definite trends in time. Arsenic, boron and molybdenum have remained at concentrations above those of shallow groundwater in areas unaffected by settling pond seepage. 11 refs., 10 figs., 1 tab.

  8. Ground-Water Quality Data in the Central Sierra Study Unit, 2006 - Results from the California GAMA Program

    USGS Publications Warehouse

    Ferrari, Matthew J.; Fram, Miranda S.; Belitz, Kenneth

    2008-01-01

    Ground-water quality in the approximately 950 square kilometer (370 square mile) Central Sierra study unit (CENSIE) was investigated in May 2006 as part of the Priority Basin Assessment project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Assessment project was developed in response to the Ground-Water Quality Monitoring Act of 2001, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). This study was designed to provide a spatially unbiased assessment of the quality of raw ground water used for drinking-water supplies within CENSIE, and to facilitate statistically consistent comparisons of ground-water quality throughout California. Samples were collected from thirty wells in Madera County. Twenty-seven of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study area (grid wells), and three were selected to aid in evaluation of specific water-quality issues (understanding wells). Ground-water samples were analyzed for a large number of synthetic organic constituents (volatile organic compounds [VOCs], gasoline oxygenates and degradates, pesticides and pesticide degradates), constituents of special interest (N-nitrosodimethylamine, perchlorate, and 1,2,3-trichloropropane), naturally occurring inorganic constituents [nutrients, major and minor ions, and trace elements], radioactive constituents, and microbial indicators. Naturally occurring isotopes [tritium, and carbon-14, and stable isotopes of hydrogen, oxygen, nitrogen, and carbon], and dissolved noble gases also were measured to help identify the sources and ages of the sampled ground water. In total, over 250 constituents and water-quality indicators were investigated. Quality-control samples (blanks, replicates, and samples for matrix spikes) were collected at approximately one-sixth of the wells, and

  9. A national reconnaissance of pharmaceuticals and other organic wastewater contaminants in the United States - I) Groundwater

    USGS Publications Warehouse

    Barnes, K.K.; Kolpin, D.W.; Furlong, E.T.; Zaugg, S.D.; Meyer, M.T.; Barber, L.B.

    2008-01-01

    As part of the continuing effort to collect baseline information on the environmental occurrence of pharmaceuticals, and other organic wastewater contaminants (OWCs) in the Nation's water resources, water samples were collected from a network of 47 groundwater sites across 18 states in 2000. All samples collected were analyzed for 65 OWCs representing a wide variety of uses and origins. Site selection focused on areas suspected to be susceptible to contamination from either animal or human wastewaters (i.e. down gradient of a landfill, unsewered residential development, or animal feedlot). Thus, sites sampled were not necessarily used as a source of drinking water but provide a variety of geohydrologic environments with potential sources of OWCs. OWCs were detected in 81% of the sites sampled, with 35 of the 65 OWCs being found at least once. The most frequently detected compounds include N,N-diethyltoluamide (35%, insect repellant), bisphenol A (30%, plasticizer), tri(2-chloroethyl) phosphate (30%, fire retardant), sulfamethoxazole (23%, veterinary and human antibiotic), and 4-octylphenol monoethoxylate (19%, detergent metabolite). Although sampling procedures were intended to ensure that all groundwater samples analyzed were indicative of aquifer conditions it is possible that detections of some OWCs could have resulted from leaching of well-construction materials and/or other site-specific conditions related to well construction and materials. Future research will be needed to identify those factors that are most important in determining the occurrence and concentrations of OWCs in groundwater.

  10. 2012 Groundwater Monitoring Report Project Shoal Area Subsurface Corrective Action Unit 447

    SciTech Connect

    2013-03-01

    The Project Shoal Area (PSA) in Nevada was the site of a 12-kiloton underground nuclear test in 1963. Although the surface of the site has been remediated, investigation of groundwater contamination resulting from the test is still in the corrective action process. Annual sampling and hydraulic head monitoring are conducted at the site as part of the subsurface corrective action strategy. Analytical results from the 2012 monitoring are consistent with those of the previous years, with tritium detected only in well HC-4. The tritium concentration in groundwater from well HC-4 remains far below the U.S. Environmental Protection Agency-established maximum contaminant level of 20,000 picocuries per liter. Concentrations of total uranium and gross alpha were also detected during this monitoring period, with uranium accounting for nearly all the gross alpha activity. The total uranium concentrations obtained from this monitoring period were consistent with previous results and reflect a slightly elevated natural uranium concentration, consistent with the mineralized geologic terrain. Isotopic ratios of uranium also indicate a natural source of uranium in groundwater, as opposed to a nuclear-test-related source. Water level trends obtained from the 2012 water level data were consistent with those of previous years. The corrective action strategy for the PSA is currently focused on revising the site conceptual model (SCM) and evaluating the adequacy of the current monitoring well network. Some aspects of the SCM are known; however, two major concerns are the uncertainty in the groundwater flow direction and the cause of rising water levels in site wells west of the shear zone. Water levels have been rising in the site wells west of the shear zone since the first hydrologic characterization wells were installed in 1996. While water levels in wells west of the shear zone continue to rise, the rate of increase is less than in previous years. The SCM will be revised, and an

  11. In situ treatment of mixed contaminants in groundwater: Review of candidate processes

    SciTech Connect

    Korte, N.E.; Siegrist, R.L.; Ally, M.

    1994-10-01

    This document describes the screening and preliminary evaluation of candidate treatment for use in treating mixed contaminants volatile organic compounds (VOCs) and radionuclides in groundwater. Treating mixed contaminants presents unusual difficulties. Typically, VOCs are the most abundant contaminants, but the presence of radionuclides results in additional health concerns that must be addressed, usually by a treatment approach different from that used for VOCs. Furthermore, the presence of radionuclides may yield mixed solid wastes if the VOCs are treated by conventional means. These issues were specifically addressed in the evaluation of candidate treatment processes for testing in this program. Moreover, because no research or early development of a particular process would be performed, the technology review also focused on technologies that could be readily adapted and integrated for use with mixed contaminants. The objective is to couple emerging or available processes into treatment modules for use in situ. The three year project, to be completed in September 1996, includes a full-scale field demonstration. The findings reported in this document encompass all activities through the treatment process evaluations.

  12. Effects of residential wastewater treatment systems on ground-water quality in west-central Jefferson County, Colorado

    USGS Publications Warehouse

    Hall, Dennis C.; Hillier, D.E.; Nickum, Edward; Dorrance, W.G.

    1981-01-01

    The use of residential wastewater-treatment systems in Evergreen Meadows, Marshdale, and Herzman Mesa, Colo., has degraded ground-water quality to some extent in each community. Age of community; average lot size; slope of land surface; composition, permeability, and thickness of surficial material; density, size , and orientation of fractures; maintenance of wastewater-treatment systems; and presence of animals are factors possibly contributing to the degradation of ground-water quality. When compared with effluent from aeration-treatment tanks, effluent fom septic-treatment tanks is characterized by greater biochemical oxygen demand and greater concentrations of detergents. When compared with effluent from septic-treatment tanks, effluent from aeration-treatment tanks is characterized by greater concentrations of dissolved oxygen, nitrite, nitrate, sulfate, and dissolved solids. (USGS)

  13. Characterization of the anaerobic denitrification bacterium Acinetobacter sp. SZ28 and its application for groundwater treatment.

    PubMed

    Su, Jun feng; Zheng, Sheng Chen; Huang, Ting lin; Ma, Fang; Shao, Si Cheng; Yang, Shao Fei; Zhang, Li na

    2015-09-01

    Acinetobacter sp. SZ28 exhibited efficient autotrophic denitrification ability using Mn(2+) as an electron donor. Sequence amplification identified the presence of the nirS gene. Meteorological chromatography analysis showed that N2 was produced as an end product. Response surface methodology experiments showed that the maximum removal of nitrate occurred under the following conditions: Mn(2+) concentration of 143.56 mg/L, C/N ratio of 6.82, initial pH of 5.17, and temperature of 34.26 °C, where the initial Mn(2+) concentration produced the largest effect. In the groundwater experiment, nitrate levels decreased from 1.63 mg/L to 0 mg/L. Three-dimensional fluorescence analysis showed a decrease in the peak intensity of the original humus. Humus and the small-molecule amino acid tryptophan were detected. These results demonstrated that strain SZ28 is a suitable candidate for the simultaneous removal of nitrogen and Mn(2+) in groundwater treatment. PMID:26094190

  14. California GAMA Program: Ground-Water Quality Data in the Northern San Joaquin Basin Study Unit, 2005

    USGS Publications Warehouse

    Bennett, George L.; Belitz, Kenneth; Milby Dawson, Barbara J.

    2006-01-01

    Growing concern over the closure of public-supply wells because of ground-water contamination has led the State Water Board to establish the Ground-Water Ambient Monitoring and Assessment (GAMA) Program. With the aid of the U.S. Geological Survey (USGS) and Lawrence Livermore National Laboratory, the program goals are to enhance understanding and provide a current assessment of ground-water quality in areas where ground water is an important source of drinking water. The Northern San Joaquin Basin GAMA study unit covers an area of approximately 2,079 square miles (mi2) across four hydrologic study areas in the San Joaquin Valley. The four study areas are the California Department of Water Resources (CADWR) defined Tracy subbasin, the CADWR-defined Eastern San Joaquin subbasin, the CADWR-defined Cosumnes subbasin, and the sedimentologically distinct USGS-defined Uplands study area, which includes portions of both the Cosumnes and Eastern San Joaquin subbasins. Seventy ground-water samples were collected from 64 public-supply, irrigation, domestic, and monitoring wells within the Northern San Joaquin Basin GAMA study unit. Thirty-two of these samples were collected in the Eastern San Joaquin Basin study area, 17 in the Tracy Basin study area, 10 in the Cosumnes Basin study area, and 11 in the Uplands Basin study area. Of the 32 samples collected in the Eastern San Joaquin Basin, 6 were collected using a depth-dependent sampling pump. This pump allows for the collection of samples from discrete depths within the pumping well. Two wells were chosen for depth-dependent sampling and three samples were collected at varying depths within each well. Over 350 water-quality field parameters, chemical constituents, and microbial constituents were analyzed and are reported as concentrations and as detection frequencies, by compound classification as well as for individual constituents, for the Northern San Joaquin Basin study unit as a whole and for each individual study area

  15. Hydrogeologic framework and estimates of ground-water volumes in Tertiary and upper Cretaceous hydrogeologic units in the Powder River basin, Wyoming

    USGS Publications Warehouse

    Hinaman, Kurt

    2005-01-01

    The Powder River Basin in Wyoming and Montana is an important source of energy resources for the United States. Coalbed methane gas is contained in Tertiary and upper Cretaceous hydrogeologic units in the Powder River Basin. This gas is released when water pressure in coalbeds is lowered, usually by pumping ground water. Issues related to disposal and uses of by-product water from coalbed methane production have developed, in part, due to uncertainties in hydrologic properties. One hydrologic property of primary interest is the amount of water contained in Tertiary and upper Cretaceous hydrogeologic units in the Powder River Basin. The U.S. Geological Survey, in cooperation with the Bureau of Land Management, conducted a study to describe the hydrogeologic framework and to estimate ground-water volumes in different facies of Tertiary and upper Cretaceous hydrogeologic units in the Powder River Basin in Wyoming. A geographic information system was used to compile and utilize hydrogeologic maps, to describe the hydrogeologic framework, and to estimate the volume of ground water in Tertiary and upper Cretaceous hydrogeologic units in the Powder River structural basin in Wyoming. Maps of the altitudes of potentiometric surfaces, altitudes of the tops and bottoms of hydrogeologic units, thicknesses of hydrogeologic units, percent sand of hydrogeologic units, and outcrop boundaries for the following hydrogeologic units were used: Tongue River-Wasatch aquifer, Lebo confining unit, Tullock aquifer, Upper Hell Creek confining unit, and the Fox Hills-Lower Hell Creek aquifer. Literature porosity values of 30 percent for sand and 35 percent for non-sand facies were used to calculate the volume of total ground water in each hydrogeologic unit. Literature specific yield values of 26 percent for sand and 10 percent for non-sand facies, and literature specific storage values of 0.0001 ft-1 (1/foot) for sand facies and 0.00001 ft-1 for non-sand facies, were used to calculate a

  16. Groundwater geochemical and selected volatile organic compound data, Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington, June 2011

    USGS Publications Warehouse

    Huffman, Raegan L.; Frans, L.M.

    2012-01-01

    Previous investigations indicate that concentrations of chlorinated volatile organic compounds are substantial in groundwater beneath the 9-acre former landfill at Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington. Phytoremediation combined with ongoing natural attenuation processes was the preferred remedy selected by the U.S. Navy, as specified in the Record of Decision for the site. The U.S. Navy planted two hybrid poplar plantations on the landfill in spring 1999 to remove and to control the migration of chlorinated volatile organic compounds in shallow groundwater. The U.S. Geological Survey has continued to monitor groundwater geochemistry to ensure that conditions remain favorable for contaminant biodegradation as specified in the Record of Decision. This report presents groundwater geochemical and selected volatile organic compound data collected at Operable Unit 1 by the U.S. Geological Survey during June 20-22, 2011, in support of long-term monitoring for natural attenuation. In 2011, groundwater samples were collected from 13 wells and 9 piezometers. Samples from all wells and piezometers were analyzed for redox sensitive constituents and dissolved gases, and samples from 5 of 13 wells and all piezometers also were analyzed for chlorinated volatile organic compounds. Concentrations of redox sensitive constituents measured in 2011 were consistent with previous years, with dissolved oxygen concentrations all at 0.4 milligram per liter or less; little to no detectable nitrate; abundant dissolved manganese, iron, and methane; and commonly detected sulfide. The reductive declorination byproducts - methane, ethane, and ethene - were either not detected in samples collected from the upgradient wells in the landfill and the upper aquifer beneath the northern phytoremediation plantation or were detected at concentrations less than those measured in 2010. Chlorinated volatile organic compound concentrations in 2011 at most piezometers

  17. Data management implementation plan for the site characterization of the Waste Area Grouping 1 Groundwater Operable Unit at Oak Ridge National Laboratory

    SciTech Connect

    Ball, T.S.; Nickle, E.B.

    1994-10-01

    The Waste Area Grouping (WAG) 1 Groundwater Operable Unit (OU) at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee, is undergoing a site characterization. This project is not mandated by the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA); therefore, no formalized meetings for data quality objective (DQO) development were held. Internally, DQOs were generated by the project team based on the end uses of the data to be collected. The 150-acre WAG 1 is contained within the ORNL security area. It includes all of the former ORNL radioisotope research, production, and maintenance facilities; former waste management areas; and some former administrative facilities. The goal of the WAG 1 Groundwater Site Characterization is to provide the necessary data on the nature and extent of groundwater contamination with an acceptable level of uncertainty to support the selection of remedial alternatives and to identify additional data needs for future actions. Primary objectives for the site characterization are: (1) To identify and characterize contaminant migration pathways based on the collection of groundwater data; (2) to identify sources of groundwater contamination and evaluate remedial actions which could be implemented to control or eliminate these sources; and (3) To conduct groundwater monitoring in support of other OUs in WAG 1 and the ORNL Groundwater OU.

  18. Ground-Water Flow Model of the Sierra Vista Subwatershed and Sonoran Portions of the Upper San Pedro Basin, Southeastern Arizona, United States, and Northern Sonora, Mexico

    USGS Publications Warehouse

    Pool, D.R.; Dickinson, Jesse E.

    2007-01-01

    A numerical ground-water model was developed to simulate seasonal and long-term variations in ground-water flow in the Sierra Vista subwatershed, Arizona, United States, and Sonora, Mexico, portions of the Upper San Pedro Basin. This model includes the simulation of details of the groundwater flow system that were not simulated by previous models, such as ground-water flow in the sedimentary rocks that surround and underlie the alluvial basin deposits, withdrawals for dewatering purposes at the Tombstone mine, discharge to springs in the Huachuca Mountains, thick low-permeability intervals of silt and clay that separate the ground-water flow system into deep-confined and shallow-unconfined systems, ephemeral-channel recharge, and seasonal variations in ground-water discharge by wells and evapotranspiration. Steady-state and transient conditions during 1902-2003 were simulated by using a five-layer numerical ground- water flow model representing multiple hydrogeologic units. Hydraulic properties of model layers, streamflow, and evapotranspiration rates were estimated as part of the calibration process by using observed water levels, vertical hydraulic gradients, streamflow, and estimated evapotranspiration rates as constraints. Simulations approximate observed water-level trends throughout most of the model area and streamflow trends at the Charleston streamflow-gaging station on the San Pedro River. Differences in observed and simulated water levels, streamflow, and evapotranspiration could be reduced through simulation of climate-related variations in recharge rates and recharge from flood-flow infiltration.

  19. Treatment of contaminated groundwater in sandy layer under river bank by electrokinetic and ultrasonic technology.

    PubMed

    Chung, Ha I

    2007-01-01

    A series of laboratory experiments involving simple, ultrasonic, electrokinetic, electrokinetic/ ultrasonic flushing test were carried out for treatment and removal of heavy metal and hydrocarbon from contaminated groundwater in sandy layers under a river bank. The test results show that the electrokinetic/ultrasonic flushing technique is most effective for the removal of heavy metal and hydrocarbon from contaminated sandy layers by the coupling action of their own phenomena. It is shown that the electrokinetic technique is most effective to enhance the removal efficiency of heavy metal contaminants such as cadmium from contaminated sandy soil under the river bank; on the other hand the ultrasonic technique is most effective to enhance the removal efficiency of hydrocarbon contaminant, such as diesel fuel from contaminated soil. PMID:17305157

  20. Phytoremediation of explosives in groundwater using innovative wetlands-based treatment technologies

    SciTech Connect

    Sikora, F.J.; Behrends, L.L.; Coonrod, H.S.; Phillips, W.D.; Bader, D.F.

    1997-12-31

    Many army ammunition plants across the country have problems with groundwater contaminated with explosives. A field demonstration was initiated at the Milan Army Ammunition Plant near Milan, Tennessee early in 1996 to demonstrate the feasibility of treating contaminated groundwater with constructed wetlands. Two different systems were designed and installed. A lagoon system consisted of two cells in series with each cell having dimensions of 24 x 9.4 x 0.6 m (L x W x H). A gravel-bed system consisted of three gravel-beds operated in series with a primary anaerobic cell having dimensions of 32 x 11 x 1.4 m (L x W x H), followed by a pair of secondary cells each with dimensions of 5.5 x 11 x 1.4 m (L x W x H). The primary cell is maintained anaerobic by adding powdered milk to the water every two weeks. The secondary cells are maintained aerobic via reciprocation, whereby water is pumped back and forth from one cell to another to cause a recurrent fill and drain action. The lagoons were planted with sago pond weed, water stargrass, elodea, and parrot feather. The gravel-bed wetlands were planted with canary grass, wool grass, sweet flag, and parrot feather. Water began flowing to each of the wetland treatment systems at 19 L min{sup {minus}1} starting in June 1996. The design hydraulic retention time through each treatment system was approximately 10 days. Influent and effluent water samples were collected every 2 weeks. Intensive sampling of water interior to the wetlands occurred every 2 months.

  1. A containment and disposition strategy for tritium contaminated groundwater at the Savannah River Site, South Carolina, United States.

    SciTech Connect

    Hitchcock, Daniel; Barton, Christopher, D.; Rebel, Karin, T.; Singer, Julian; Seaman, John, C.; Strawbridge, Dan; Riha, Susan, J.; Blake, John, I.

    2005-03-01

    Hitchcock, Daniel R., C.D. Barton, K.T. Rebel, J. Singer, J.C. Seaman, J.D. Strawbridge, S.J. Riha, and J.I. Blake. 2005. A containment and disposition strategy for tritium-contaminated groundwater at the Savannah River Site, South Carolina, United States.. Env. Geosci. 12(1): 17-28. Abstract - A containment and disposition water management strategy has been implemented at the Savannah River Site to minimize the discharge of tritiated groundwater from the Old Radioactive Waste Burial Ground to Four Mile Branch, a tributary of the Savannah River. This paper presents a general overview of the water management strategy, which includes a two-component (pond and irrigation) system, and a summary of operations and effectiveness for the first 3 yr of operations. Tritiated groundwater seep discharge was impounded by a dam and distributed via irrigation to a 22-ac (8.9-ha) upland forested area comprised of mixed pines (loblolly and slash) and hardwoods(primarily sweetgum and laurel oak). As of March 2004, the system has irrigated approximately 133.2 million L (35.2 million gal) and prevented approximately 1880 Ci of tritium from entering Four Mile Branch via forest evapotranspiration, as well as via pond storage and evaporation. Prior to installation of the containment and disposition strategy, tritium activity in Four Mile Branch downstream of the seep averaged approximately 500 pCi mL_1. Six months after installation, tritium activity averaged approximately 200 pCi mL_1 in Fourmile Branch. After 1 yr of operations, tritium activity averaged below 100 pCi mL_1 in Fourmile Branch, and a range of 100-200 pCi mL_1 tritium activity has been maintained as of March 2004. Complex hydrological factors and operational strategies influence remediation system success. Analyses may assist in developing groundwater management and remediation strategies for future projects at the Savannah River Site and other facilities located on similar landscapes.

  2. Reactive barrier technologies for treatment of contaminated groundwater at Rocky Flats

    SciTech Connect

    Marozas, D.C.; Bujewski, G.E.; Castaneda, N.

    1997-12-31

    The U.S. Department of Energy (DOE) Office of Science and Technology Subsurface Contaminants Focus Area is supporting the investigation of reactive barrier technologies to mitigate the risks associated with mixed organic/radioactive waste at several DOE sites. Groundwater from a small contaminated plume at the Rocky Flats Environmental Technology Site (RFETS) is being used to evaluate passive reactive material treatment. Permeable reactive barriers which intercept contaminants and destroy the VOC component while containing radionuclides are attractive for a number of reasons relating to public and regulatory acceptance. In situ treatment keeps contaminants away from the earth`s surface, there is no above-ground treatment equipment that could expose workers and the public and operational costs are expected to be lower than currently used technologies. This paper will present results from preliminary site characterization and in-field small-scale column testing of reactive materials at RFETS. Successful demonstration is expected to lead to full-scale implementation of the technology at several DOE sites, including Rocky Flats.

  3. Occurrence and treatment of arsenic in groundwater and soil in northern Mexico and southwestern USA.

    PubMed

    Camacho, Lucy Mar; Gutiérrez, Mélida; Alarcón-Herrera, Maria Teresa; Villalba, Maria de Lourdes; Deng, Shuguang

    2011-04-01

    This review focuses on the occurrence and treatment of arsenic (As) in the arid region of northern Mexico (states of Chihuahua and Coahuila) and bordering states of the southwestern US (New Mexico, Arizona, and Texas), an area known for having high As concentrations. Information assembled and assessed includes the content and probable source of As in water, soil, and sediments and treatment methods that have been applied in the area. High As concentrations were found mainly in groundwater, their source being mostly from natural origin related to volcanic processes with significant anthropogenic contributions near mining and smelting of ores containing arsenic. The affinity of As for solid phases in alkaline conditions common to arid areas precludes it from being present in surface waters, accumulating instead in sediments and shifting its threat to its potential remobilization in reservoir sediments and irrigation waterways. Factors such as oxidation and pH that affect the mobility of As in the subsurface environment are mentioned. Independent of socio-demographic variables, nutritional status, and levels of blood lead, cognitive development in children is being affected when exposed to As. Treatments known to effectively reduce As content to safe drinking water levels as well as those that are capable of reducing As content in soils are discussed. Besides conventional methods, emergent technologies, such as phytoremediation, offer a viable solution to As contamination in drinking water. PMID:21216433

  4. Groundwater Model Validation for the Project Shoal Area, Corrective Action Unit 447

    SciTech Connect

    2008-05-19

    Stoller has examined newly collected water level data in multiple wells at the Shoal site. On the basis of these data and information presented in the report, we are currently unable to confirm that the model is successfully validated. Most of our concerns regarding the model stem from two findings: (1) measured water level data do not provide clear evidence of a prevailing lateral flow direction; and (2) the groundwater flow system has been and continues to be in a transient state, which contrasts with assumed steady-state conditions in the model. The results of DRI's model validation efforts and observations made regarding water level behavior are discussed in the following sections. A summary of our conclusions and recommendations for a path forward are also provided in this letter report.

  5. VOCs, pesticides, nitrate, and their mixtures in groundwater used for drinking water in the United States

    USGS Publications Warehouse

    Squillace, P.J.; Scott, J.C.; Moran, M.J.; Nolan, B.T.; Kolpin, D.W.

    2002-01-01

    Samples of untreated groundwater from 1255 domestic drinking-water wells and 242 public supply wells were analyzed as part of the National Water-Quality Assessment Program of the U.S. Geological Survey between 1992 and 1999. Wells were sampled to define the regional quality of the groundwater resource and, thus, were distributed geographically across large aquifers, primarily in rural areas. For each sample, as many as 60 volatile organic compounds (VOCs), 83 pesticides, and nitrate were analyzed. On the basis of previous studies, nitrate concentrations as nitrogen ≥3 mg/L were considered to have an anthropogenic origin. VOCs were detected more frequently (44%) than pesticides (38%) or anthropogenic nitrate (28%). Seventy percent of the samples contained at least one VOC, pesticide, or anthropogenic nitrate; 47% contained at least two compounds; and 33% contained at least three compounds. The combined concentrations of VOCs and pesticides ranged from about 0.001 to 100 μg/L, with a median of 0.02 μg/L. Water from about 12% of the wells contained one or more compounds that exceeded U.S. Environmental Protection Agency drinking-water standards or human health criteria, primarily because of nitrate concentrations exceeding the maximum contaminant level in domestic wells. A mixture is defined as a unique combination of two or more particular compounds, regardless of the presence of other compounds that may occur in the same sample. There were 100 mixtures (significantly associated with agricultural land use) that had a detection frequency between 2% and 19%. There were 302 mixtures (significantly associated with urban land use) that had a detection frequency between 1% and <2%. Only 14 compounds (seven VOCs, six pesticides, and nitrate) contributed over 95% of the detections in these 402 mixtures; however, most samples with these mixtures also contain a variety of other compounds.

  6. 2012 Groundwater Monitoring Report Central Nevada Test Area, Subsurface Corrective Action Unit 443

    SciTech Connect

    2013-04-01

    The Central Nevada Test Area was the site of a 0.2- to 1-megaton underground nuclear test in 1968. The surface of the site has been closed, but the subsurface is still in the corrective action process. The corrective action alternative selected for the site was monitoring with institutional controls. Annual sampling and hydraulic head monitoring are conducted as part of the subsurface corrective action strategy. The site is currently in the fourth year of the 5-year proof-of-concept period that is intended to validate the compliance boundary. Analytical results from the 2012 monitoring are consistent with those of previous years. Tritium remains at levels below the laboratory minimum detectable concentration in all wells in the monitoring network. Samples collected from reentry well UC-1-P-2SR, which is not in the monitoring network but was sampled as part of supplemental activities conducted during the 2012 monitoring, indicate concentrations of tritium that are consistent with previous sampling results. This well was drilled into the chimney shortly after the detonation, and water levels continue to rise, demonstrating the very low permeability of the volcanic rocks. Water level data from new wells MV-4 and MV-5 and recompleted well HTH-1RC indicate that hydraulic heads are still recovering from installation and testing. Data from wells MV-4 and MV-5 also indicate that head levels have not yet recovered from the 2011 sampling event during which several thousand gallons of water were purged. It has been recommended that a low-flow sampling method be adopted for these wells to allow head levels to recover to steady-state conditions. Despite the lack of steady-state groundwater conditions, hydraulic head data collected from alluvial wells installed in 2009 continue to support the conceptual model that the southeast-bounding graben fault acts as a barrier to groundwater flow at the site.

  7. VOCs in shallow groundwater in new residential/commercial areas of the United States

    USGS Publications Warehouse

    Squillace, P.J.; Moran, M.J.; Price, C.V.

    2004-01-01

    The quality of shallow groundwater in urban areas was investigated by sampling 518 monitoring wells between 1996 and 2002 as part of the National Water-Quality Assessment Program of the U.S. Geological Survey. Well networks were installed primarily in new residential/commercial areas less than about 30 years old (17 studies) and in small towns (2 studies) by randomly locating as many as 30 monitoring wells in each study area. The median well depth was 10 m. Based on samples with age-date information, almost all groundwater was recharged after 1950. Samples were analyzed for 53 volatile organic compounds (VOCs). Concentrations ranged from about 0.001 to 1000 ??g/L (median 0.04), with less than 1% of the samples exceeding a Maximum Contamination Level or Drinking Water Advisory established by the U.S. Environmental Protection Agency. Using uncensored concentration data, at least one VOC was detected in 88% of the samples, and at least two VOCs were detected in 69% of the samples. Chloroform, toluene, and perchloroethene were the three most frequently detected VOCs. Dissolved oxygen concentration, estimated recharge index, and land-use were significant variables in logistic regression models that explained the presence of the commonly detected VOCs. Dissolved oxygen concentration was the most important explanatory variable in logistic regression models for 6 of the 14 most frequently detected VOCs. Bromodichloromethane, chloroform, and 1,1,1-trichloroethane had a positive correlation with dissolved oxygen; in contrast, dichloroethane, benzene, and toluene had a negative correlation with dissolved oxygen.

  8. Supporting evaluation for the proposed plan for final remedial action for the groundwater operable unit at the chemical plant area of the Weldon Spring Site, Weldon Spring, Missouri.

    SciTech Connect

    2003-08-06

    This report presents the technical information developed since the interim record of decision (IROD) was issued in September 2000 (U.S. Department of Energy [DOE] 2000). The information was incorporated into the evaluation that was performed in selecting the preferred alternative for the Chemical Plant groundwater operable unit (GWOU) of the Weldon Spring site. The contaminants of concern (COCs) in groundwater and springs are trichloroethylene (TCE), nitrate, uranium, and nitroaromatic compounds. The preferred alternative of monitored natural attenuation (MNA) coupled with institutional controls (ICs) and contingency activities is described in the ''Proposed Plan (PP) for Final Remedial Action for the Groundwater Operable Unit at the Chemical Plant Area of the Weldon Spring Site, Weldon Spring, Missouri'' (DOE 2003b).

  9. Construction of the Largest Radionuclide Commingled Plume Groundwater Treatment Facility for the Department of Energy at the Hanford Site - 12411

    SciTech Connect

    Pargmann, Delise

    2012-07-01

    CH2M Hill Plateau Remediation Company (CHPRC) has constructed the largest groundwater treatment systems of its kind throughout the DOE Complex at the Hanford Site in an accelerated manner with American Recovery and Reinvestment Act (ARRA) funds. This complex, one of a kind groundwater treatment facility in Washington State has also attained Leadership in Energy and Environmental Design (LEED) Gold certification. The original concept for the 200 West Area groundwater treatment facility was a 6100 liter per minute (1,600 gallon per minute) facility. With additional ARRA funding, the plant design was improved to construct a 9500 liter per minute (2,500 gallon per minute) facility with expansion areas up to 14,000 liter per minute (3,750 gallon per minute). The current design will remove 53 percent more mass per year for faster clean-up. It is also expected to treat extracted groundwater to 25 percent or less than the Record of Decision-specified limit which improves Monitored Natural Attenuation (MNA) effectiveness. (author)

  10. Superfund Record of Decision (EPA Region 10): East Multnomah County Groundwater Contamination, Operable Unit 1, Multnomah County, OR, December 31, 1996

    SciTech Connect

    1998-01-01

    The East Multnomah County (EMC) project area refers to all areas in the EMC project area where the Troutdale Sandstone Aquifer (TSA) contains concentrations of halogenated volatile organic compounds at concentrations requiring remediation. The selected remedial action for the Troutdale Sandstone Aquifer (TSA) contaminant plume includes: treatment of extracted groundwater using air-stripping treatment technology; discharge of treated groundwater to Fairview Lake and the Columbia Slough directly or via Multnomah County storm water drainage ways; abandonment of six private Sand and Gravel Aquifer (SGA) water supply wells located within the area of the TSA contaminant plume and a provision to replace the abandoned wells with an alternative source of water; institutional controls to restrict groundwater use of the TSA and SGA to prevent exposure to contaminated groundwater and the spread of groundwater contamination during remediation; groundwater monitoring to assess compliance with performance criteria established for the remedy; and hydraulic containment of those areas of the TSA for which it may be technically impractical to restore to MCL cleanup levels within 20 years.

  11. Phase II Hydrologic Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 98: Frenchman Flat, Nye County, Nevada, Rev. No.: 0

    SciTech Connect

    John McCord

    2004-12-01

    This report documents pertinent hydrologic data and data analyses as part of the Phase II Corrective Action Investigation (CAI) for Frenchman Flat (FF) Corrective Action Unit (CAU): CAU 98. The purpose of this data compilation and related analyses is to provide the primary reference to support the development of the Phase II FF CAU groundwater flow model.

  12. Identification and treatment of lithium as the primary toxicant in a groundwater treatment facility effluent

    SciTech Connect

    Kszos, L.A.; Crow, K.R.

    1996-10-01

    {sup 6}Li is used in manufacturing nuclear weapons, shielding, and reactor control rods. Li compounds have been used at DOE facilities and Li-contaminated waste has historically been land disposed. Seep water from burial grounds near Y-12 contain small amounts of chlorinated hydrocarbons, traces of PCBs, and 10-19 mg/L Li. Seep treatment consists of oil-water separation, filtration, air stripping, and carbon adsorption. Routine biomonitoring tests using fathead minnows and {ital Ceriodaphnia}{ital dubia} are conducted. Evaluation of suspected contaminants revealed that toxicity was most likely due to Li. Laboratory tests showed that 1 mg Li/L reduced the survival of both species; 0.5 mg Li/L reduced {ital Ceriodaphnia} reproduction and minnow growth. However, the toxicity was greatly reduced in presence of sodium (up to 4 mg Li/L, Na can fully negate the toxic effect of Li). Because of the low Na level discharged from the treatment facility, Li removal from the ground water was desired. SuperLig{reg_sign} columns were used (Li-selective organic macrocycle bonded to silica gel). Bench-scale tests showed that the material was very effective for removing Li from the effluent, reducing the toxicity.

  13. Ground-water exploration in Al Marj area, Cyrenaica, United Kingdom of Libya

    USGS Publications Warehouse

    Newport, T.G.; Haddor, Yousef

    1963-01-01

    The present report, based largely on fieldwork during 1959-61, describes the results of reconnaissance hydrogeologic studies and exploratory drilling to evaluate the general water-bearing properties of the rocks and the availability of groundwater supplies for irrigation, stock, and village uses in Al Marj area. These studies and the drilling were conducted under the auspices of the U.S. Operations Mission of the International Cooperation Administration. Al Marj area, located in the Province of Cyrenaica on the southern coast of the Mediterranean Sea, contains a land area of about 6,770 square kilometers. Along the Mediterranean shore is a narrow coastal plain that rises evenly to the base of an escarpment that forms the seaward front of an undulating plateau known as. Al Jabal al Akhgiar. The climate is semiarid; seasonal rainfall occurs during the winter months. Owing to orographic effects, the rainfall is somewhat higher in the Jabal than in the coastal plain. The average annual rainfall ranges from about 250 millimeters in the coastal plain to 450 millimeters on the Jabal. All the streams (wadis) of the area are ephemeral and flow only in response to heavy rains of the winter season. From a drainage divide on the Jabal some streams flow north and northwest toward the sea and the others, south and southeast to the interior desert. Solution features, such as limestone sink holes, are common in the coastal plain and a large solution depression occurs near Al Marj. The rocks of A1 Marj area consist predominantly of limestone and some sandstone and shale; they range from Cretaceous to Miocene age. On the coastal plain Miocene limestone is locally mantled by Quaternary alluvial, beach and lagoonal deposits. The Miocene and older beds have a regional southerly dip. These rocks are broken by northeast-trending normal faults in the coastal and inland escarpments. The ground-water reservoir is contained chiefly in fractures, bedding planes, and solution openings in the

  14. Groundwater geochemical and selected volatile organic compound data, Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington, June 2009

    USGS Publications Warehouse

    Huffman, R.L.; Dinicola, R.S.

    2011-01-01

    Previous investigations indicate that natural attenuation and biodegradation of chlorinated volatile organic compounds (VOCs) are substantial in groundwater beneath the 9-acre former landfill at Operable Unit 1 (OU 1), Naval Undersea Warfare Center, Division Keyport, Washington. Phytoremediation combined with ongoing natural attenuation processes was the preferred remedy selected by the U.S. Navy, as specified in the Record of Decision for the site. The U.S. Navy planted two hybrid poplar plantations on the landfill in spring 1999 to remove and to control the migration of chlorinated VOCs in shallow groundwater. The U.S. Geological Survey (USGS) has continued to monitor groundwater geochemistry to ensure that conditions remain favorable for contaminant biodegradation as specified in the Record of Decision. This report presents groundwater geochemical and selected VOC data collected at OU 1 by the USGS during June 15-17, 2009, in support of long-term monitoring for natural attenuation. For 2009, groundwater samples were collected from 13 wells and 9 piezometers. Samples from all wells and piezometers were analyzed for redox sensitive constituents, and samples from 10 of 18 upper-aquifer wells and piezometers and 3 of 4 intermediate-aquifer wells also were analyzed for chlorinated VOCs. Concentrations of redox sensitive constituents measured in 2009 were consistent with previous years, with dissolved hydrogen (H2) concentrations ranging from less than 0.1 to 1.8 nanomolar (nM), dissolved oxygen concentrations all at 0.6 milligram per liter or less; little to no detectable nitrate; abundant dissolved manganese, iron, and methane; and commonly detected sulfide. The reductive declorination byproducts-methane, ethane, and ethene-were not detected in samples collected from the upgradient wells in the landfill or the upper aquifer beneath the northern phytoremediation plantation. Chlorinated VOC concentrations in 2009 at most piezometers were similar to or slightly less

  15. Qualitative risk assessment for the 100-HR-3 groundwater operable unit

    SciTech Connect

    Vukelich, S.E.

    1994-09-22

    This report provides the qualitative risk assessment for the 100-HR-3 operable unit on the Hanford Reservation. 100-HR-3 is a ground water unit. The purpose of the QRA at the 100-HR-3 operable unit is to focus on a predefined set of human and environmental exposure scenarios in order to provides sufficient information that will assist the Tri-Party signatories (Washington State Department of Ecology, EPA and US DOE) in making defensible decisions on the necessity of Interim Remedial Measures. Frequent- and occasional-use exposure scenarios are evaluated in the human health risk assessment to provide bounding estimates of risk. The ecological risk assessment consists of an evaluation of the risks to riparian and aquatic receptors which live in or near the Columbia River.

  16. B Plant treatment, storage, and disposal (TSD) units inspection plan

    SciTech Connect

    Beam, T.G.

    1996-04-26

    This inspection plan is written to meet the requirements of WAC 173-303 for operations of a TSD facility. Owners/operators of TSD facilities are required to inspection their facility and active waste management units to prevent and/or detect malfunctions, discharges and other conditions potentially hazardous to human health and the environment. A written plan detailing these inspection efforts must be maintained at the facility in accordance with Washington Administrative Code (WAC), Chapter 173-303, ``Dangerous Waste Regulations`` (WAC 173-303), a written inspection plan is required for the operation of a treatment, storage and disposal (TSD) facility and individual TSD units. B Plant is a permitted TSD facility currently operating under interim status with an approved Part A Permit. Various operational systems and locations within or under the control of B Plant have been permitted for waste management activities. Included are the following TSD units: Cell 4 Container Storage Area; B Plant Containment Building; Low Level Waste Tank System; Organic Waste Tank System; Neutralized Current Acid Waste (NCAW) Tank System; Low Level Waste Concentrator Tank System. This inspection plan complies with the requirements of WAC 173-303. It addresses both general TSD facility and TSD unit-specific inspection requirements. Sections on each of the TSD units provide a brief description of the system configuration and the permitted waste management activity, a summary of the inspection requirements, and details on the activities B Plant uses to maintain compliance with those requirements.

  17. Evaluation of the removal of Strontium-90 from groundwater using a zeolite rich-rock permeable treatment wall

    NASA Astrophysics Data System (ADS)

    Seneca, S. M.; Rabideau, A. J.; Bandilla, K.

    2010-12-01

    Experimental and modeling studies are in progress to evaluate the long-term performance of a permeable treatment wall comprised of zeolite-rich rock for the removal of strontium-90 from groundwater. Multiple column tests were performed at the University at Buffalo and on-site West Valley Environmental Services; columns were supplied with synthetic groundwater referenced to anticipate field conditions and radioactive groundwater on-site WVES. The primary focus in this work is on quantifying the competitive ion exchange among five cations (Na+, K+, Ca2+, Mg2+, and Sr2+); the data obtained from the column studies is used to support the robust estimation of zeolite cation exchange parameters. This research will produce a five-solute cation exchange model describing the removal efficiency of the zeolite, using the various column tests to calibrate and validate the geochemical transport model. The field-scale transport model provides flexibility to explore design parameters and potential variations in groundwater geochemistry to investigate the long-term performance of a full scale treatment wall at the Western New York nuclear facility.

  18. Soils and groundwater cleanup at Fernald: A status update on Operable Unit No. 5

    SciTech Connect

    Yerace, P.J.; Bomberger, A.K.; Brettschneider, D.J.

    1993-11-01

    This report discusses a status update on the cleanup operations at FERNALD. Discussed is the regulatory framework for FERNALD cleanup; overview of the FERNALD site; description of operable unit 5;remedial investigation; pattern of contamination; feasibility studies; and tangible progress to date.

  19. Agricultural chemicals in groundwater of the midwestern United States: Relations to land use

    USGS Publications Warehouse

    Kolpin, D.W.

    1997-01-01

    To determine the relations between land use and concentrations of selected agricultural chemicals (nitrate, atrazine residue [atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) + deethylatrazinc (2-amino-4-chloro-6-isopropylamino-s-triazine) + deisopropylatrazine (2-amino-4-chloro-6-ethylamino-s-triazine)], and alachlor residue [alachlor, [2-chloro-2′,6′-diethyl-N-(methoxymethyl) acetanilide] + alachlor ethanesulfonic acid (alachlor-ESA; 2-[(2,6-diethylphenyl)(methoxymethyl)amino]-2-oxoethanesulfonic acid)] in groundwater, detailed land use information based on accurate measurements from aerial photographs for the 1991 growing season was obtained within a 2-km radius surrounding 100 wells completed in near-surface unconsolidated aquifers in the midwestern USA. The most significant land use factors to the agricultural chemicals examined were: nitrate (amount of irrigated crop production, positive relation), atrazine residue (amount of irrigated crop production, positive relation), and alachlor residue (amount of highly erodible land, inverse relation). The investigation of smaller buffer sizes (size of circular area around sampled wells) proved insightful for this study. Additional land use factors having significant relations to all three agricultural chemicals were identified using these smaller buffer radii. The most significant correlations (correlation maxima) generally occurred at ≤500-m for nitrate and ≥1000-m for atrazine residue and alachlor residue. An attempt to improve the statistical relations to land use by taking hydrologic considerations into account (removing land outside the estimated most probable recharge area from the statistical analysis) was not as successful as anticipated. Only 45% of the nitrate, 32% of the atrazine residue, and 20% of the alachlor residue correlations were improved by a consideration of the estimated most probable recharge area.

  20. Effects of seepage from fly-ash settling ponds and construction dewatering on ground-water levels in the Cowles unit, Indiana Dunes National Lakeshore, Indiana

    USGS Publications Warehouse

    Meyer, William R.; Tucci, Patrick

    1979-01-01

    Part of the Indiana Dunes National Lakeshore shares a common boundary with the Northern Indiana Public Service Company (NIPSCO). This area is underlain by unconsolidated deposits approximately 180 feet thick. NIPSCO accumulates fly ash from the burning of coal in electric-power generating units in settling ponds. Seepage from the ponds has raised ground-water levels above natural levels approximately 15 feet under the ponds and more than 10 feet within the Lakeshore. NIPSCO is presently (1977) constructing a nuclear powerplant, and construction activities include pumping ground water to dewater the construction site. The company has installed a slurry wall around the site to prevent lowering of ground-water levels within the Lakeshore. Plans call for continuous pumping through at least December 1979. A multilayered digital flow model was constructed to simulate the ground-water system. The model was used to demonstrate the effects of seepage from the fly-ash ponds on ground-water levels. Also, the model indicated a decline of 3 feet or less in the upper sand unit and 5 feet or less in the lower sand unit within the Lakeshore.

  1. Fertility Treatments in the United States: Improving Access and Outcomes.

    PubMed

    Kissin, Dmitry M; Boulet, Sheree L; Jamieson, Denise J

    2016-08-01

    The recently released National Public Health Action Plan for the Detection, Prevention, and Management of Infertility calls for better access to high-quality infertility services and improved safety of fertility treatments. Both assisted reproductive technology (ART) and non-ART fertility treatments have allowed millions of patients worldwide to overcome infertility-a disease of the reproductive system and important public health issue. However, there are substantial disparities in access to effective treatments in the United States, largely attributable to high out-of-pocket costs, especially for ART. Moreover, the outcomes of fertility treatments are often complicated by the large proportion of multiple births with substantial health risks for both neonates and mothers. Prevention of multiple births is difficult during non-ART fertility treatments but can be effective with single-embryo transfer during ART. Several U.S. states have enacted legislative mandates that require private insurers to cover some portion of the costs associated with fertility treatments and thus reduce the financial pressure to transfer multiple embryos during ART. Although studies have shown that insurance coverage reduces per-cycle multiple births to a certain degree, states with insurance mandates have more ART-related multiple births attributable to substantially larger number of ART-conceived neonates. Experience from other countries shows that access to ART can be improved without concomitant increases in multiple births by providing reimbursement for ART in combination with restrictions on the number of embryos transferred per cycle. Such approaches may or may not be successful in the United States with its unique and complex health care system. PMID:27399992

  2. Status and understanding of groundwater quality in the Tahoe-Martis, Central Sierra, and Southern Sierra study units, 2006-2007--California GAMA Priority Basin Project

    USGS Publications Warehouse

    Fram, Miranda S.; Belitz, Kenneth

    2012-01-01

    Groundwater quality in the Tahoe-Martis, Central Sierra, and Southern Sierra study units was investigated as part of the Priority Basin Project of the California Groundwater Ambient Monitoring and Assessment (GAMA) Program. The three study units are located in the Sierra Nevada region of California in parts of Nevada, Placer, El Dorado, Madera, Tulare, and Kern Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board, in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The project was designed to provide statistically robust assessments of untreated groundwater quality within the primary aquifer systems used for drinking water. The primary aquifer systems (hereinafter, primary aquifers) for each study unit are defined by the depth of the screened or open intervals of the wells listed in the California Department of Public Health (CDPH) database of wells used for municipal and community drinking-water supply. The quality of groundwater in shallower or deeper water-bearing zones may differ from that in the primary aquifers; shallower groundwater may be more vulnerable to contamination from the surface. The assessments for the Tahoe-Martis, Central Sierra, and Southern Sierra study units were based on water-quality and ancillary data collected by the USGS from 132 wells in the three study units during 2006 and 2007 and water-quality data reported in the CDPH database. Two types of assessments were made: (1) status, assessment of the current quality of the groundwater resource, and (2) understanding, identification of the natural and human factors affecting groundwater quality. The assessments characterize untreated groundwater quality, not the quality of treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentrations divided by benchmark concentrations) were used for evaluating groundwater quality for those

  3. Groundwater-quality data in the Bear Valley and Selected Hard Rock Areas study unit, 2010: Results from the California GAMA Program

    USGS Publications Warehouse

    Mathany, Timothy M.; Belitz, Kenneth

    2013-01-01

    Groundwater quality in the 112-square-mile Bear Valley and Selected Hard Rock Areas (BEAR) study unit was investigated by the U.S. Geological Survey (USGS) from April to August 2010, as part of the California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and Assessment (GAMA) Program’s Priority Basin Project (PBP). The GAMA-PBP was developed in response to the California Groundwater Quality Monitoring Act of 2001 and is being conducted in collaboration with the SWRCB and Lawrence Livermore National Laboratory (LLNL). The BEAR study unit was the thirty-first study unit to be sampled as part of the GAMA-PBP. The GAMA Bear Valley and Selected Hard Rock Areas study was designed to provide a spatially unbiased assessment of untreated-groundwater quality in the primary aquifer system and to facilitate statistically consistent comparisons of untreated groundwater quality throughout California. The primary aquifer system is defined as the zones corresponding to the perforation intervals of wells listed in the California Department of Public Health (CDPH) database for the BEAR study unit. Groundwater quality in the primary aquifer system may differ from the quality in the shallow or deep water-bearing zones; shallow groundwater may be more vulnerable to surficial contamination. In the BEAR study unit, groundwater samples were collected from two study areas (Bear Valley and Selected Hard Rock Areas) in San Bernardino County. Of the 38 sampling sites, 27 were selected by using a spatially distributed, randomized grid-based method to provide statistical representation of the primary aquifer system in the study unit (grid sites), and the remaining 11 sites were selected to aid in the understanding of the potential groundwater-quality issues associated with septic tank use and with ski areas in the study unit (understanding sites). The groundwater samples were analyzed for organic constituents (volatile organic compounds [VOCs], pesticides and

  4. Status of groundwater quality in the Southern, Middle, and Northern Sacramento Valley study units, 2005-08: California GAMA Priority Basin Project

    USGS Publications Warehouse

    Bennett, George L.; Fram, Miranda S.; Belitz, Kenneth

    2011-01-01

    Groundwater quality in the Southern, Middle, and Northern Sacramento Valley study units was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study units are located in California's Central Valley and include parts of Butte, Colusa, Glenn, Placer, Sacramento, Shasta, Solano, Sutter, Tehama, Yolo, and Yuba Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey and the Lawrence Livermore National Laboratory. The three study units were designated to provide spatially-unbiased assessments of the quality of untreated groundwater in three parts of the Central Valley hydrogeologic province, as well as to provide a statistically consistent basis for comparing water quality regionally and statewide. Samples were collected in 2005 (Southern Sacramento Valley), 2006 (Middle Sacramento Valley), and 2007-08 (Northern Sacramento Valley). The GAMA studies in the Southern, Middle, and Northern Sacramento Valley were designed to provide statistically robust assessments of the quality of untreated groundwater in the primary aquifer systems that are used for drinking-water supply. The assessments are based on water-quality data collected by the USGS from 235 wells in the three study units in 2005-08, and water-quality data from the California Department of Public Health (CDPH) database. The primary aquifer systems (hereinafter, referred to as primary aquifers) assessed in this study are defined by the depth intervals of the wells in the CDPH database for each study unit. The quality of groundwater in shallow or deep water-bearing zones may differ from quality of groundwater in the primary aquifers; shallow groundwater may be more vulnerable to contamination from the surface. The status of the current quality of the groundwater resource was assessed by using data from samples analyzed for volatile organic

  5. Fluoride removal from groundwater by limestone treatment in presence of phosphoric acid.

    PubMed

    Gogoi, Sweety; Nath, Suresh K; Bordoloi, Shreemoyee; Dutta, Robin K

    2015-04-01

    Fluoride removal from groundwater has been studied by addition of dilute phosphoric acid (PA) to the influent water before limestone treatment through laboratory plug-flow column experiments and bench-scale plug-flow pilot tests. In this PA-enhanced limestone defluoridation (PAELD) technique, fluoride is removed from 0.526 mM to 0.50-52.60 μM in 3 h with near neutral final pH. The presence of PA increases the fluoride removal capacity of limestone to 1.10 mg/g compared to 0.39 mg/g reported in its absence. The changes in fluoride removal with variation in initial PA concentration, initial fluoride concentration and the final pH have been found to be statistically significant with p < 0.05. The estimated recurring cost is US$ ≈0.58/m(3) water. Simple scrubbing and rinsing is a preferable method for regeneration of limestone as it is almost equally effective with lime or NaOH. Sorption of fluoride by calcium phosphates produced in situ in the reactor is the dominant mechanism of fluoride removal in the PAELD. Precipitation of CaF2 and sorption of fluoride by the limestone also contribute to the fluoride removal. High efficiency, capacity, safety, environment-friendliness, low cost and simplicity of operation make the PAELD a potential technique for rural application. PMID:25621387

  6. REACTIVE BARRIER TREATMENT WALL TECHNOLOGY FOR REMEDIATION OF INORGANIC CONTAMINATED GROUNDWATER

    SciTech Connect

    T. TAYLOR; ET AL

    2001-03-01

    The potential for subsurface reactive barrier wall technology to aid in remediation of contaminated groundwater in situ has prompted testing of novel porous media. Treatability testing of contaminants contacted with various media has been conducted using equilibrium batch techniques, one-dimensional (1-D) columns and 2-D boxes. Continuous mode column and box experiments are useful for assessing critical design parameters under dynamic flow conditions. Experiments have been conducted using a multi-layer barrier treatment approach to immobilize a suite of contaminants. For example, basalt coated with a cationic polymer (poly diallyl dimethyl ammonium chloride [Catfloc{reg_sign}]) was used to agglomerate colloids, Apatite II{reg_sign} sorbed aqueous phase metals and radionuclides including {sup 85,87}Sr and {sup 235}U and facilitated reduction of nitrate and perchlorate, crushed pecan shells sorbed aqueous phase metals and served as a secondary medium for reduction of nitrate and perchlorate concentrations, and finally limestone raised the pH of exiting pore waters close to natural levels.

  7. Sampling and analysis plan for the site characterization of the waste area Grouping 1 groundwater operable unit at Oak Ridge National Laboratory

    SciTech Connect

    1994-11-01

    Waste Area Grouping (WAG) 1 at Oak Ridge National Laboratory (ORNL) includes all of the former ORNL radioisotope research, production, and maintenance facilities; former waste management areas; and some former administrative buildings. Site operations have contaminated groundwater, principally with radiological contamination. An extensive network of underground pipelines and utilities have contributed to the dispersal of contaminants to a known extent. In addition, karst geology, numerous spills, and pipeline leaks, together with the long and varied history of activities at specific facilities at ORNL, complicate contaminant migration-pathway analysis and source identification. To evaluate the extent of contamination, site characterization activity will include semiannual and annual groundwater sampling, as well as monthly water level measurements (both manual and continuous) at WAG 1. This sampling and analysis plan provides the methods and procedures to conduct site characterization for the Phase 1 Remedial Investigation of the WAG 1 Groundwater Operable Unit.

  8. Application of a geographic information system in analyzing the occurrence of atrazine in groundwater of the mid-continental United States

    USGS Publications Warehouse

    Burkart, M.R.; Kolpin, D.W.

    1993-01-01

    The US Geological Survey, US Department of Agriculture, and US Environmental Protection Agency are conducting research and regional assessments in support of policy alternatives intended to protect water resources from agricultural chemical contamination. The mid-continent was selected because of the intense row crop agriculture and associated herbicide application in this region. An application of a geographic information system is demonstrated for analyzing and comparing the distribution of estimated atrazine use to the detection rate of atrazine in groundwater. Understanding the relations between atrazine use and detection in groundwater is important in policy deliberations to protect water resources. Relational analyses between measures of chemical use and detection rate by natural resource units may provide insight into critical factors controlling the processes that result in groundwater contamination from agricultural chemicals. 

  9. Chloride in Groundwater and Surface Water in Areas Underlain by the Glacial Aquifer System, Northern United States

    USGS Publications Warehouse

    Mullaney, John R.; Lorenz, David L.; Arntson, Alan D.

    2009-01-01

    A study of chloride in groundwater and surface water was conducted for the glacial aquifer system of the northern United States in forested, agricultural, and urban areas by analyzing data collected for the National Water-Quality Assessment Program from 1991 to 2004. Groundwater-quality data from a sampling of 1,329 wells in 19 states were analyzed. Chloride concentrations were greater than the secondary maximum contaminant level established by the U.S. Environmental Protection Agency of 250 milligrams per liter in 2.5 percent of samples from 797 shallow monitoring wells and in 1.7 percent of samples from 532 drinking-water supply wells. Water samples from shallow monitoring wells in urban areas had the largest concentration of chloride, followed by water samples from agricultural and forested areas (medians of 46, 12, and 2.9 milligrams per liter, respectively). An analysis of chloride:bromide ratios, by mass, and chloride concentrations compared to binary mixing curves for dilute groundwater, halite, sewage and animal waste, potassium chloride fertilizer, basin brines, seawater, and landfill leachate in samples from monitoring wells indicated multiple sources of chloride in samples from wells in urban areas and agricultural areas. Water from shallow monitoring wells in urban areas had the largest chloride:bromide ratio, and samples with chloride:bromide ratios greater than 1,000 and chloride concentrations greater than 100 milligrams per liter were dominated by halite; however, the samples commonly contained mixtures that indicated input from sewage or animal waste. Chloride:bromide ratios were significantly larger in samples from public-supply drinking-water wells than from private drinking-water wells, and ratios were significantly larger in all drinking-water wells in eastern and central regions of the glacial aquifer system than in west-central and western regions of the glacial aquifer system. Surface-water-quality data collected regularly during varying

  10. Status and understanding of groundwater quality in the two southern San Joaquin Valley study units, 2005-2006 - California GAMA Priority Basin Project

    USGS Publications Warehouse

    Burton, Carmen A.; Shelton, Jennifer L.; Belitz, Kenneth

    2012-01-01

    Groundwater quality in the southern San Joaquin Valley was investigated from October 2005 through March 2006 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project is conducted by the U.S. Geological Survey (USGS) in collaboration with the California State Water Resources Control Board and the Lawrence Livermore National Laboratory. There are two study units located in the southern San Joaquin Valley: the Southeast San Joaquin Valley (SESJ) study unit and the Kern County Subbasin (KERN) study unit. The GAMA Priority Basin Project in the SESJ and KERN study units was designed to provide a statistically unbiased, spatially distributed assessment of untreated groundwater quality within the primary aquifers. The status assessment is based on water-quality and ancillary data collected in 2005 and 2006 by the USGS from 130 wells on a spatially distributed grid, and water-quality data from the California Department of Public Health (CDPH) database. Data was collected from an additional 19 wells for the understanding assessment. The aquifer systems (hereinafter referred to as primary aquifers) were defined as that part of the aquifer corresponding to the perforation interval of wells listed in the CDPH database for the SESJ and KERN study units. The status assessment of groundwater quality used data from samples analyzed for anthropogenic constituents such as volatile organic compounds (VOCs) and pesticides, as well as naturally occurring inorganic constituents such as major ions and trace elements. The status assessment is intended to characterize the quality of untreated groundwater resources within the primary aquifers in the SESJ and KERN study units, not the quality of drinking water delivered to consumers. Although the status assessment applies to untreated groundwater, Federal and California regulatory and non-regulatory water-quality benchmarks that apply to drinking water are used

  11. Phase II Groundwater Flow Model of Corrective Action Unit 98: Frenchman Flat, Nevada Test Site, Nye County, Nevada, Rev. No.: 0

    SciTech Connect

    John McCord

    2006-05-01

    The Phase II Frenchman Flat groundwater flow model is a key element in the ''Federal Facility Agreement and Consent Order'' (FFACO) (1996) corrective action strategy for the Underground Test Area (UGTA) Frenchman Flat corrective action unit (CAU). The objective of this integrated process is to provide an estimate of the vertical and horizontal extent of contaminant migration for each CAU to predict contaminant boundaries. A contaminant boundary is the model-predicted perimeter that defines the extent of radionuclide-contaminated groundwater from underground testing above background conditions exceeding the ''Safe Drinking Water Act'' (SDWA) standards. The contaminant boundary will be composed of both a perimeter boundary and a lower hydrostratigraphic unit (HSU) boundary. The computer model will predict the location of this boundary within 1,000 years and must do so at a 95 percent level of confidence. Additional results showing contaminant concentrations and the location of the contaminant boundary at selected times will also be presented. These times may include the verification period, the end of the five-year proof-of-concept period, as well as other times that are of specific interest. This report documents the development and implementation of the groundwater flow model for the Frenchman Flat CAU. Specific objectives of the Phase II Frenchman Flat flow model are to: (1) Incorporate pertinent information and lessons learned from the Phase I Frenchman Flat CAU models. (2) Develop a three-dimensional (3-D), mathematical flow model that incorporates the important physical features of the flow system and honors CAU-specific data and information. (3) Simulate the steady-state groundwater flow system to determine the direction and magnitude of groundwater fluxes based on calibration to Frenchman Flat hydrogeologic data. (4) Quantify the uncertainty in the direction and magnitude of groundwater flow due to uncertainty in parameter values and alternative component

  12. Geochemical and Isotopic Evaluation of Groundwater Movement in Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada Test Site, Nevada, Rev. No.: 0

    SciTech Connect

    Farnham, Irene

    2006-02-01

    This report describes the results of a comprehensive geochemical evaluation of the groundwater flow system in the Yucca Flat/Climax Mine Corrective Action Unit (CAU). The main objectives of this study are to identify probable pathways for groundwater flow within the study area and to develop constraints on groundwater transit times between selected data collection sites. This work provides an independent means of testing and verifying predictive flow models being developed for this CAU using finite element methods. The Yucca Flat/Climax Mine CAU constitutes the largest of six underground test areas on the Nevada Test Site (NTS) specified for remedial action in the ''Federal Facility Agreement and Consent Order''. A total of 747 underground nuclear detonations were conducted in this CAU. Approximately 23 percent of these detonations were conducted below or near the water table, resulting in groundwater contamination in the vicinity and possibly downgradient of these underground test locations. Therefore, a rigorous evaluation of the groundwater flow system in this CAU is necessary to assess potential long-term risks to the public water supply at downgradient locations.

  13. Treatment of Perchlorate-Contaminated Groundwater Using Highly-Selective, Regenerable Anion-Exchange Resins at Edwards Air Force Base

    SciTech Connect

    Gu, B.

    2003-05-30

    Selective ion exchange is one of the most effective treatment technologies for removing low levels of perchlorate (ClO{sub 4}{sup -}) from contaminated water because of its high efficiency without adverse impacts on the water quality caused by adding or removing any chemicals or nutrients. This report summarizes both the laboratory and a field pilot-scale studies to determine the ability and efficiency of the bifunctional synthetic resins to remove ClO{sub 4}{sup -} from the contaminated groundwater at the Edwards Air Force Base in California. Regeneration of the resins after groundwater treatment was also evaluated using the FeCl{sub 3}-HCl regeneration technique recently developed at Oak Ridge National Laboratory. On the basis of this study, the bifunctional resin, D-3696 was found to be highly selective toward ClO{sub 4}{sup -} and performed much better than one of the best commercial nitrate-selective resins (Purolite A-520E) and more than an order of magnitude better than the Purolite A-500 resin (with a relatively low selectivity). At an influent concentration of {approx} 450 {micro}g/L ClO{sub 4}{sup -} in groundwater, the bifunctional resin bed treated {approx} 40,000 empty bed volumes of groundwater before a significant breakthrough of ClO{sub 4}{sup -} occurred. The presence of relatively high concentrations of chloride and sulfate in site groundwater did not appear to affect the ability of the bifunctional resin to remove ClO{sub 4}{sup -}. However, the presence of high iron or iron oxyhydroxides and/or biomass in groundwater caused a significant fouling of the resin beds and greatly influenced the effectiveness in regenerating the resins sorbed with ClO{sub 4}{sup -}. Under such circumstances, a prefilter ({approx} 0.5-1 {micro}m) was found to be necessary to remove these particulates and to reduce the risk of fouling of the resin beds. Without significant fouling, the resin bed could be effectively regenerated by the FeCl{sub 3} displacement technique

  14. Understanding the hydrologic impacts of wastewater treatment plant discharge to shallow groundwater: before and after plant shutdown

    USGS Publications Warehouse

    Hubbard, Laura E.; Keefe, Steffanie H.; Kolpin, Dana W.; Barber, Larry B.; Duris, Joseph; Hutchinson, Kasey J.; Bradley, Paul M.

    2016-01-01

    Effluent-impacted surface water has the potential to transport not only water, but wastewater-derived contaminants to shallow groundwater systems. To better understand the effects of effluent discharge on in-stream and near-stream hydrologic conditions in wastewater-impacted systems, water-level changes were monitored in hyporheic-zone and shallow-groundwater piezometers in a reach of Fourmile Creek adjacent to and downstream of the Ankeny (Iowa, USA) wastewater treatment plant (WWTP). Water-level changes were monitored from approximately 1.5 months before to 0.5 months after WWTP closure. Diurnal patterns in WWTP discharge were closely mirrored in stream and shallow-groundwater levels immediately upstream and up to 3 km downstream of the outfall, indicating that such discharge was the primary control on water levels before shutdown. The hydrologic response to WWTP shutdown was immediately observed throughout the study reach, verifying the far-reaching hydraulic connectivity and associated contaminant transport risk. The movement of WWTP effluent into alluvial aquifers has implications for potential WWTP-derived contamination of shallow groundwater far removed from the WWTP outfall.

  15. The neurovascular unit and combination treatment strategies for stroke

    PubMed Central

    Zhang, Li; Zhang, Zhang Gang; Chopp, Michael

    2012-01-01

    Tissue plasminogen activator (tPA) administered within 4.5 hours of symptom onset restores cerebral blood flow and promotes neurological recovery of stroke patients. However, the narrow therapeutic time window and the risk of intracerebral hemorrhage after tPA treatment pose major hurdles to its clinical usage. In light of the failures of neuroprotective therapies in clinical trials, emerging concepts suggest that neuroprotection alone without restoration of tissue perfusion and vascular integrity may not be adequate for treatment of acute stroke. Here we review evidence of the use of adjuvant pharmacological agents to extend the therapeutic window for tPA via targeting the neurovascular unit and the underlying mechanisms of the combination therapy in experimental stroke. PMID:22595494

  16. Probability of nitrate contamination of recently recharged groundwaters in the conterminous United States

    USGS Publications Warehouse

    Nolan, B.T.; Hitt, K.J.; Ruddy, B.C.

    2002-01-01

    A new logistic regression (LR) model was used to predict the probability of nitrate contamination exceeding 4 mg/L in predominantly shallow, recently recharged ground waters of the United States. The new model contains variables representing (1) N fertilizer loading (p 2 = 0.875), indicating that the LR model fits the data well. The likelihood of nitrate contamination is greater in areas with high N loading and well-drained surficial soils over unconsolidated sand and gravels. The LR model correctly predicted the status of nitrate contamination in 75% of wells in a validation data set. Considering all wells used in both calibration and validation, observed median nitrate concentration increased from 0.24 to 8.30 mg/L as the mapped probability of nitrate exceeding 4 mg/L increased from less than or equal to 0.17 to > 0.83.

  17. PERMEABLE REACTIVE BARRIERS FOR IN-SITU TREATMENT OF ARSENIC-CONTAMINATED GROUNDWATER

    EPA Science Inventory

    Laboratory and field research has shown that permeable reactive barriers (PRBs) containing a variety of materials can treat arsenic (As) contaminated groundwater. Sites where these PRBs are located include a mine tailings facility, fertilizer and chemical manufacturing sites, a...

  18. Framework for a Risk-Informed Groundwater Compliance Strategy for Corrective Action Unit 98: Frenchman Flat, Nevada National Security Site, Nye County, Nevada, Revision 1

    SciTech Connect

    Marutzky, Sam

    2010-09-01

    Note: This document was prepared before the NTS was renamed the Nevada National Security Site (August 23, 2010); thus, all references to the site herein remain NTS. Corrective Action Unit (CAU) 98, Frenchman Flat, at the Nevada Test Site (NTS) was the location of ten underground nuclear tests between 1965 and 1971. As a result, radionuclides were released in the subsurface in the vicinity of the test cavities. Corrective Action Unit 98 and other CAUs at the NTS and offsite locations are being investigated. The Frenchman Flat CAU is one of five Underground Test Area (UGTA) CAUs at the NTS that are being evaluated as potential sources of local or regional impact to groundwater resources. For UGTA sites, including Frenchman Flat, contamination in and around the test cavities will not be remediated because it is technologically infeasible due to the depth of the test cavities (150 to 2,000 feet [ft] below ground surface) and the volume of contaminated groundwater at widely dispersed locations on the NTS. Instead, the compliance strategy for these sites is to model contaminant flow and transport, estimate the maximum spatial extent and volume of contaminated groundwater (over a period of 1,000 years), maintain institutional controls, and restrict access to potentially contaminated groundwater at areas where contaminants could migrate beyond the NTS boundaries.

  19. ANNUAL REPORT FOR THE FINAL GROUNDWATER REMEDIATION, TEST AREA NORTH, OPERABLE UNIT 1-07B, FISCAL YEAR 2009

    SciTech Connect

    FORSYTHE, HOWARD S

    2010-04-14

    This Annual Report presents the data and evaluates the progress of the three-component remedy implemented for remediation of groundwater contamination at Test Area North, Operable Unit 1-07B, at the Idaho National Laboratory Site. Overall, each component is achieving progress toward the goal of total plume remediation. In situ bioremediation operations in the hot spot continue to operate as planned. Progress toward the remedy objectives is being made, as evidenced by continued reduction in the amount of accessible residual source and decreases in downgradient contaminant flux, with the exception of TAN-28. The injection strategy is maintaining effective anaerobic reductive dechlorination conditions, as evidenced by complete degradation of trichloroethene and ethene production in the biologically active wells. In the medial zone, the New Pump and Treat Facility operated in standby mode. Trichloroethene concentrations in the medial zone wells are significantly lower than the historically defined concentration range of 1,000 to 20,000 μg/L. The trichloroethene concentrations in TAN-33, TAN-36, and TAN-44 continue to be below 200 μg/L. Monitoring in the distal zone wells outside and downgradient of the plume boundary demonstrate that some plume expansion has occurred, but less than the amount allowed in the Record of Decision Amendment. Additional data need to be collected for wells in the monitored natural attenuation part of the plume to confirm that the monitored natural attenuation part of the remedy is proceeding as predicted in the modeling.

  20. Field evaluation of a horizontal well recirculation system for groundwater treatment: Pilot test at the Clean Test Site Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    SciTech Connect

    Muck, M.T.; Kearl, P.M.; Siegrist, R.L.

    1998-08-01

    This report presents the results of field testing a horizontal well recirculation system at the Portsmouth Gaseous Diffusion Plant (PORTS). The recirculation system uses a pair of horizontal wells, one for groundwater extraction and treatment and the other for reinjection of treated groundwater, to set up a recirculation flow field. The induced flow field from the injection well to the extraction well establishes a sweeping action for the removal and treatment of groundwater contaminants. The overall purpose of this project is to study treatment of mixed groundwater contaminants that occur in a thin water-bearing zone not easily targeted by traditional vertical wells. The project involves several research elements, including treatment-process evaluation, hydrodynamic flow and transport modeling, pilot testing at an uncontaminated site, and pilot testing at a contaminated site. The results of the pilot test at an uncontaminated site, the Clean Test Site (CTS), are presented in this report.

  1. Contributions of Phosphorus from Groundwater to Streams in the Piedmont, Blue Ridge, and Valley and Ridge Physiographic Provinces, Eastern United States

    USGS Publications Warehouse

    Denver, Judith M.; Cravotta, Charles A., III; Ator, Scott W.; Lindsey, Bruce D.

    2011-01-01

    Phosphorus from natural and human sources is likely to be discharged from groundwater to streams in certain geochemical environments. Water-quality data collected from 1991 through 2007 in paired networks of groundwater and streams in different hydrogeologic and land-use settings of the Piedmont, Blue Ridge, and Valley and Ridge Physiographic Provinces in the eastern United States were compiled and analyzed to evaluate the sources, fate, and transport of phosphorus. The median concentrations of phosphate in groundwater from the crystalline and siliciclastic bedrock settings (0.017 and 0.020 milligrams per liter, respectively) generally were greater than the median for the carbonate setting (less than 0.01 milligrams per liter). In contrast, the median concentrations of dissolved phosphate in stream base flow from the crystalline and siliciclastic bedrock settings (0.010 and 0.014 milligrams per liter, respectively) were less than the median concentration for base-flow samples from the carbonate setting (0.020 milligrams per liter). Concentrations of phosphorus in many of the stream base-flow and groundwater samples exceeded ecological criteria for streams in the region. Mineral dissolution was identified as the dominant source of phosphorus in the groundwater and stream base flow draining crystalline or siliciclastic bedrock in the study area. Low concentrations of dissolved phosphorus in groundwater from carbonate bedrock result from the precipitation of minerals and (or) from sorption to mineral surfaces along groundwater flow paths. Phosphorus concentrations are commonly elevated in stream base flow in areas underlain by carbonate bedrock, however, presumably derived from in-stream sources or from upland anthropogenic sources and transported along short, shallow groundwater flow paths. Dissolved phosphate concentrations in groundwater were correlated positively with concentrations of silica and sodium, and negatively with alkalinity and concentrations of calcium

  2. Status and understanding of groundwater quality in the South Coast Range-Coastal study unit, 2008: California GAMA Priority Basin Project

    USGS Publications Warehouse

    Burton, Carmen A.; Land, Michael; Belitz, Kenneth

    2013-01-01

    Groundwater quality in the South Coast Range–Coastal (SCRC) study unit was investigated from May through November 2008 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is located in the Southern Coast Range hydrologic province and includes parts of Santa Barbara and San Luis Obispo Counties. The GAMA Priority Basin Project is conducted by the U.S. Geological Survey (USGS) in collaboration with the California State Water Resources Control Board and the Lawrence Livermore National Laboratory. The GAMA Priority Basin Project was designed to provide a statistically unbiased, spatially distributed assessment of untreated groundwater quality within the primary aquifer system. The primary aquifer system is defined as that part of the aquifer corresponding to the perforation interval of wells listed in the California Department of Public Health (CDPH) database for the SCRC study unit. The assessments for the SCRC study unit were based on water-quality and ancillary data collected in 2008 by the USGS from 55 wells on a spatially distributed grid, and water-quality data from the CDPH database. Two types of assessments were made: (1) status, assessment of the current quality of the groundwater resource, and (2) understanding, identification of the natural and human factors affecting groundwater quality. Water-quality and ancillary data were collected from an additional 15 wells for the understanding assessment. The assessments characterize untreated groundwater quality, not the quality of treated drinking water delivered to consumers by water purveyors. The first component of this study, the status assessment of groundwater quality, used data from samples analyzed for anthropogenic constituents such as volatile organic compounds (VOCs) and pesticides, as well as naturally occurring inorganic constituents such as major ions and trace elements. Although the status assessment applies to untreated

  3. Feasibility study for remedial action for the groundwater operable units at the chemical plant area and the ordnance works area, Weldon Spring, Missouri

    SciTech Connect

    1999-07-15

    The U.S. Department of Energy (DOE) and the U.S. Department of Army (DA) are conducting an evaluation to identify the appropriate response action to address groundwater contamination at the Weldon Spring Chemical Plant (WSCP) and the Weldon Spring Ordnance Works (WSOW), respectively. The two areas are located in St. Charles County, about 48 km (30 rni) west of St. Louis. The groundwater operable unit (GWOU) at the WSCP is one of four operable units being evaluated by DOE as part of the Weldon Spring Site Remedial Action Project (WSSRAP). The groundwater operable unit at the WSOW is being evaluated by the DA as Operable Unit 2 (OU2); soil and pipeline contamination are being managed under Operable Unit 1 (OU1). Remedial activities at the WSCP and the WSOW are being conducted in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). Consistent with DOE policy, National Environmental Policy Act (NEPA) values have been incorporated into the CERCLA process. A remedial investigation/feasibility study (RI/FS) work plan summarizing initial site conditions and providing site hydrogeological and exposure models was published in August of 1995 (DOE 1995). The remedial investigation (RI) and baseline risk assessment (BRA) have also recently been completed. The RI (DOE and DA 1998b) discusses in detail the nature, extent, fate, and transport of groundwater and spring water contamination. The BRA (DOE and DA 1998a) is a combined baseline assessment of potential human health and ecological impacts and provides the estimated potential health risks and ecological impacts associated with groundwater and springwater contamination if no remedial action were taken. This feasibility study (FS) has been prepared to evaluate potential options for addressing groundwater contamination at the WSCP and the WSOW. A brief description of the history and environmental setting of the sites is presented in Section 1.1, key information relative to the

  4. Baseline risk assessment for groundwater operable units at the Chemical Plant Area and the Ordnance Works Area, Weldon Spring, Missouri

    SciTech Connect

    1999-07-14

    The U.S. Department of Energy (DOE) and the U.S. Department of the Army (DA) are evaluating conditions in groundwater and springs at the DOE chemical plant area and the DA ordnance works area near Weldon Spring, Missouri. The two areas are located in St. Charles County, about 48 km (30 mi) west of St. Louis. The 88-ha (217-acre) chemical plant area is chemically and radioactively contaminated as a result of uranium-processing activities conducted by the U.S. Atomic Energy Commission in the 1950s and 1960s and explosives-production activities conducted by the U.S. Army (Army) in the 1940s. The 6,974-ha (17,232-acre) ordnance works area is primarily chemically contaminated as a result of trinitrotoluene (TNT) and dinitrotoluene (DNT) manufacturing activities during World War II. This baseline risk assessment (BRA) is being conducted as part of the remedial investigation/feasibility study (RUFS) required under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980, as amended. The purpose of the BRA is to evaluate potential human health and ecological impacts from contamination associated with the groundwater operable units (GWOUs) of the chemical plant area and ordnance works area. An RI/FS work plan issued jointly in 1995 by the DOE and DA (DOE 1995) analyzed existing conditions at the GWOUs. The work plan included a conceptual hydrogeological model based on data available when the report was prepared; this model indicated that the aquifer of concern is common to both areas. Hence, to optimize further data collection and interpretation efforts, the DOE and DA have decided to conduct a joint RI/BRA. Characterization data obtained from the chemical plant area wells indicate that uranium is present at levels slightly higher than background, with a few concentrations exceeding the proposed U.S. Environmental Protection Agency (EPA) maximum contaminant level (MCL) of 20 {micro}g/L (EPA 1996c). Concentrations of other radionuclides (e

  5. Treatment of symptomatic macromastia in a breast unit

    PubMed Central

    2010-01-01

    Background Patients suffering from symptomatic macromastia are usually underserved, as they have to put up with very long waiting lists and are usually selected under restrictive criteria. The Oncoplastic Breast Surgery subspeciality requires a cross-specialty training, which is difficult, in particular, for trainees who have a background in general surgery, and not easily available. The introduction of reduction mammaplasty into a Breast Cancer Unit as treatment for symptomatic macromastia could have a synergic effect, making the scarce therapeutic offer at present available to these patients, who are usually treated in Plastic Departments, somewhat larger, and accelerating the uptake of oncoplastic training as a whole and, specifically, the oncoplastic breast conserving procedures based on the reduction mammaplasty techniques such as displacement conservative techniques and onco-therapeutic mammaplasty. This is a retrospective study analyzing the outcome of reduction mammaplasty for symptomatic macromastia in our Breast Cancer Unit. Methods A cohort study of 56 patients who underwent bilateral reduction mammaplasty at our Breast Unit between 2005 and 2009 were evaluated; morbidity and patient satisfaction were considered as end points. Data were collected by reviewing medical records and interviewing patients. Results Eight patients (14.28%) presented complications in the early postoperative period, two of them being reoperated on. The physical symptoms disappeared or significantly improved in 88% of patients and the degree of satisfaction with the care process and with the overall outcome were really high. Conclusion Our experience of the introduction of reduction mammaplasty in our Breast Cancer Unit has given good results, enabling us to learn the use of different reduction mammaplasty techniques using several pedicles which made it posssible to perform oncoplastic breast conserving surgery. In our opinion, this management policy could bring clear advantages

  6. [Treatment in the Intensive Care Unit: continue or withdraw?].

    PubMed

    Savelkoul, Claudia; de Graeff, Nienke; Kompanje, Erwin J O; Tjan, Dave H T

    2016-01-01

    End-of-life decision-making in the Intensive Care Unit is a common and complex process. The step-by-step process of decision-making leading to withdrawal of life-sustaining treatment is illustrated in this paper by a clinical case. A variety of factors influences the decision to adjust the initial curative treatment policy towards withdrawal of life-sustaining therapy and the pursuit of comfort care. For a smooth decision-making process, it is necessary to make a prognosis and obtain consensus amongst the healthcare team. Withdrawal of life-sustaining treatment is ultimately a medical decision and a consensual decision should be reached by all medical staff and nurses, and preferably also by the patient and family. Timely involvement of a legal representative of the patient is essential for an uncomplicated decision-making process. Advance care planning and advance directives provide opportunities for patients to express their preferences beforehand. It is important to realise that end-of-life decisions are significantly influenced by personal and cultural values. PMID:27050494

  7. Targeting the neurovascular unit for treatment of neurological disorders

    PubMed Central

    VanGilder, Reyna L.; Rosen, Charles L.; Barr, Taura L.; Huber, Jason D.

    2011-01-01

    Drug discovery for CNS disorders has been restricted by the inability for therapeutic agents to cross the blood-brain barrier (BBB). Moreover, current drugs aim to correct neuron cell signaling, thereby neglecting pathophysiological changes affecting other cell types of the neurovascular unit (NVU). Components of the NVU (pericytes, microglia, astrocytes, and neurons, and basal lamina) act as an intricate network to maintain the neuronal homeostatic microenvironment. Consequently, disruptions to this intricate cell network lead to neuron malfunction and symptoms characteristic of CNS diseases. A lack of understanding in NVU signaling cascades may explain why current treatments for CNS diseases are not curative. Current therapies treat symptoms by maintaining neuron function. Refocusing drug discovery to sustain NVU function may provide a better method of treatment by promoting neuron survival. In this review, we will examine current therapeutics for common CNS diseases, describe the importance of the NVU in cerebral homeostasis and discuss new possible drug targets and technologies that aim to improve treatment and drug delivery to the diseased brain. PMID:21172386

  8. A contribution to solve the arsenic problem in groundwater of Ganges Delta by in-situ treatment.

    PubMed

    Rott, U; Kauffmann, H

    2008-01-01

    Arsenic in groundwater is a huge problem in numerous regions of the world. Many people are exposed to high arsenic concentrations and consequently risk getting ill or even die as a result of arsenic poisoning. There are several efficient technologies for the removal of arsenic but often these methods have disadvantages, e.g. high costs for installation and/or operation, the need for chemicals or the production of arsenic contaminated filter sludge. These disadvantages can make the application difficult, especially in poor regions. Under suitable ancillary conditions the subterranean (in-situ) treatment, which is often used for iron and manganese removal from groundwater, can also be applied for the removal of arsenic and can be a cost-effective treatment technology. A field trial was carried out with a low-cost in-situ treatment plant in West Bengal/India which is described in this paper, in order to investigate whether this treatment technology is also applicable under the boundary conditions there. As for the in-situ treatment technology besides oxygen no additives are required and no arsenic contaminated filter sludge is produced this technology could be a suitable method for arsenic removal especially in poor regions. PMID:19039182

  9. MODFLOW-2000, the U.S. Geological Survey Modular Ground-Water Model -Documentation of the Hydrogeologic-Unit Flow (HUF) Package

    USGS Publications Warehouse

    Anderman, E.R.; Hill, M.C.

    2000-01-01

    This report documents the Hydrogeologic-Unit Flow (HUF) Package for the groundwater modeling computer program MODFLOW-2000. The HUF Package is an alternative internal flow package that allows the vertical geometry of the system hydrogeology to be defined explicitly within the model using hydrogeologic units that can be different than the definition of the model layers. The HUF Package works with all the processes of MODFLOW-2000. For the Ground-Water Flow Process, the HUF Package calculates effective hydraulic properties for the model layers based on the hydraulic properties of the hydrogeologic units, which are defined by the user using parameters. The hydraulic properties are used to calculate the conductance coefficients and other terms needed to solve the ground-water flow equation. The sensitivity of the model to the parameters defined within the HUF Package input file can be calculated using the Sensitivity Process, using observations defined with the Observation Process. Optimal values of the parameters can be estimated by using the Parameter-Estimation Process. The HUF Package is nearly identical to the Layer-Property Flow (LPF) Package, the major difference being the definition of the vertical geometry of the system hydrogeology. Use of the HUF Package is illustrated in two test cases, which also serve to verify the performance of the package by showing that the Parameter-Estimation Process produces the true parameter values when exact observations are used.

  10. Effects of natural and human factors on groundwater quality of basin-fill aquifers in the southwestern United States-conceptual models for selected contaminants

    USGS Publications Warehouse

    Bexfield, Laura M.; Thiros, Susan A.; Anning, David W.; Huntington, Jena M.; McKinney, Tim S.

    2011-01-01

    As part of the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program, the Southwest Principal Aquifers (SWPA) study is building a better understanding of the factors that affect water quality in basin-fill aquifers in the Southwestern United States. The SWPA study area includes four principal aquifers of the United States: the Basin and Range basin-fill aquifers in California, Nevada, Utah, and Arizona; the Rio Grande aquifer system in New Mexico and Colorado; and the California Coastal Basin and Central Valley aquifer systems in California. Similarities in the hydrogeology, land- and water-use practices, and water-quality issues for alluvial basins within the study area allow for regional analysis through synthesis of the baseline knowledge of groundwater-quality conditions in basins previously studied by the NAWQA Program. Resulting improvements in the understanding of the sources, movement, and fate of contaminants are assisting in the development of tools used to assess aquifer susceptibility and vulnerability. This report synthesizes previously published information about the groundwater systems and water quality of 15 information-rich basin-fill aquifers (SWPA case-study basins) into conceptual models of the primary natural and human factors commonly affecting groundwater quality with respect to selected contaminants, thereby helping to build a regional understanding of the susceptibility and vulnerability of basin-fill aquifers to those contaminants. Four relatively common contaminants (dissolved solids, nitrate, arsenic, and uranium) and two contaminant classes (volatile organic compounds (VOCs) and pesticide compounds) were investigated for sources and controls affecting their occurrence and distribution above specified levels of concern in groundwater of the case-study basins. Conceptual models of factors that are important to aquifer vulnerability with respect to those contaminants and contaminant classes were subsequently formed. The

  11. Remedial Process Optimization and Green In-Situ Ozone Sparging for Treatment of Groundwater Impacted with Petroleum Hydrocarbons

    NASA Astrophysics Data System (ADS)

    Leu, J.

    2012-12-01

    A former natural gas processing station is impacted with TPH and BTEX in groundwater. Air sparging and soil vapor extraction (AS/AVE) remediation systems had previously been operated at the site. Currently, a groundwater extraction and treatment system is operated to remove the chemicals of concern (COC) and contain the groundwater plume from migrating offsite. A remedial process optimization (RPO) was conducted to evaluate the effectiveness of historic and current remedial activities and recommend an approach to optimize the remedial activities. The RPO concluded that both the AS/SVE system and the groundwater extraction system have reached the practical limits of COC mass removal and COC concentration reduction. The RPO recommended an in-situ chemical oxidation (ISCO) study to evaluate the best ISCO oxidant and approach. An ISCO bench test was conducted to evaluate COC removal efficiency and secondary impacts to recommend an application dosage. Ozone was selected among four oxidants based on implementability, effectiveness, safety, and media impacts. The bench test concluded that ozone demand was 8 to 12 mg ozone/mg TPH and secondary groundwater by-products of ISCO include hexavalent chromium and bromate. The pH also increased moderately during ozone sparging and the TDS increased by approximately 20% after 48 hours of ozone treatment. Prior to the ISCO pilot study, a capture zone analysis (CZA) was conducted to ensure containment of the injected oxidant within the existing groundwater extraction system. The CZA was conducted through a groundwater flow modeling using MODFLOW. The model indicated that 85%, 90%, and 95% of an injected oxidant could be captured when a well pair is injecting and extracting at 2, 5, and 10 gallons per minute, respectively. An ISCO pilot test using ozone was conducted to evaluate operation parameters for ozone delivery. The ozone sparging system consisted of an ozone generator capable of delivering 6 lbs/day ozone through two ozone

  12. Groundwater quality in the San Francisco Bay groundwater basins, California

    USGS Publications Warehouse

    Parsons, Mary C.; Kulongoski, Justin T.; Belitz, Kenneth

    2013-01-01

    Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. Selected groundwater basins of the San Francisco Bay area constitute one of the study units being evaluated.

  13. PO*WW*ER mobile treatment unit process hazards analysis

    SciTech Connect

    Richardson, R.B.

    1996-06-01

    The objective of this report is to demonstrate that a thorough assessment of the risks associated with the operation of the Rust Geotech patented PO*WW*ER mobile treatment unit (MTU) has been performed and documented. The MTU was developed to treat aqueous mixed wastes at the US Department of Energy (DOE) Albuquerque Operations Office sites. The MTU uses evaporation to separate organics and water from radionuclides and solids, and catalytic oxidation to convert the hazardous into byproducts. This process hazards analysis evaluated a number of accident scenarios not directly related to the operation of the MTU, such as natural phenomena damage and mishandling of chemical containers. Worst case accident scenarios were further evaluated to determine the risk potential to the MTU and to workers, the public, and the environment. The overall risk to any group from operation of the MTU was determined to be very low; the MTU is classified as a Radiological Facility with low hazards.

  14. Rabies: What If I Receive Treatment Outside the United States?

    MedlinePlus

    ... 2008 Rabies in Domestic Animals, 1958-2008 Rabid Cats Reported in the United States, 2008 Rabid Dogs ... Reported in the United States during 2009 Rabid Cats Reported in the United States during 2009 Rabid ...

  15. Treatment of TNT contaminated soil and groundwater using plant-based enzyme systems

    SciTech Connect

    Medina, V.F.; Wolfe, L.; McCutcheon, S.C.

    1995-12-31

    Trinitrotoluene (TNT) is considered toxic and a mutagen. For over 100 years, TNT has been widely used in explosives for both military and commercial applications. Soil and groundwater contamination by TNT is prevalent at military bases, manufacturing facilities and at commercial (such as mining) sites were TNT was used or stored. TNT is a difficult compound to treat. It is resistant to complete microbial degradation. Although incineration is feasible, it can be costly. One promising technology is degradation using plant enzyme systems, which has become known as phytoremediation. This paper will highlight bench and field studies of phytoremediation of TNT contaminated soil and groundwater. Parameters for developing a model will be discussed.

  16. Documentation of a computer program to simulate transient leakage from confining units using the modular finite-difference, ground-water flow model

    USGS Publications Warehouse

    Leake, S.A.; Leahy, P.P.; Navoy, A.S.

    1994-01-01

    Transient leakage into or out of a compressible fine-grained confining unit results from ground- water storage changes within the unit. The computer program described in this report provides a new method of simulating transient leakage using the U.S. Geological Survey modular finite- difference ground-water flow model (MODFLOW). The new program is referred to as the Transient- Leakage Package. The Transient-Leakage Package solves integrodifferential equations that describe flow across the upper and lower boundaries of confining units. For each confining unit, vertical hydraulic conductivity, thickness, and specific storage are specified in input arrays. These properties can vary from cell to cell and the confining unit need not be present at all locations in the grid; however, the confining units must be bounded above and below by model layers in which head is calculated or specified. The package was used in an example problem to simulate drawdown around a pumping well in a system with two aquifers separated by a confining unit. For drawdown values in excess of 1 centimeter, the solution using the new package closely matched an exact analytical solution. The problem also was simulated without the new package by using a separate model layer to represent the confining unit. That simulation was refined by using two model layers to represent the confining unit. The simulation using the Transient-Leakage Package was faster and more accurate than either of the simulations using model layers to represent the confining unit.

  17. CE: Inside an Ebola Treatment Unit: A Nurse's Report.

    PubMed

    Wilson, Deborah

    2015-12-01

    In December 2013, the first cases of the most recent outbreak of Ebola virus disease (formerly known as Ebola hemorrhagic fever) emerged in the West African nation of Guinea. Within months the disease had spread to the neighboring countries of Liberia and Sierra Leone. The international humanitarian aid organization Médecins Sans Frontières (MSF; known in English as Doctors Without Borders) soon responded by sending staff to set up treatment centers and outreach triage teams in all three countries. In August 2014, the World Health Organization declared the outbreak an international public health emergency.In September 2014, the author was sent by MSF to work as a nurse in an Ebola treatment unit in Liberia for five weeks. This article describes her experiences there. It provides some background, outlines the practices and teams involved, and aims to convey a sense of what it's like to work during an Ebola outbreak and to put a human face on this devastating epidemic. PMID:26559159

  18. Integrated Waste Treatment Unit GFSI Risk Management Plan

    SciTech Connect

    W. A. Owca

    2007-06-21

    This GFSI Risk Management Plan (RMP) describes the strategy for assessing and managing project risks for the Integrated Waste Treatment Unit (IWTU) that are specifically within the control and purview of the U.S. Department of Energy (DOE), and identifies the risks that formed the basis for the DOE contingency included in the performance baseline. DOE-held contingency is required to cover cost and schedule impacts of DOE activities. Prior to approval of the performance baseline (Critical Decision-2) project cost contingency was evaluated during a joint meeting of the Contractor Management Team and the Integrated Project Team for both contractor and DOE risks to schedule and cost. At that time, the contractor cost and schedule risk value was $41.3M and the DOE cost and schedule risk contingency value is $39.0M. The contractor cost and schedule risk value of $41.3M was retained in the performance baseline as the contractor's management reserve for risk contingency. The DOE cost and schedule risk value of $39.0M has been retained in the performance baseline as the DOE Contingency. The performance baseline for the project was approved in December 2006 (Garman 2006). The project will continue to manage to the performance baseline and change control thresholds identified in PLN-1963, ''Idaho Cleanup Project Sodium-Bearing Waste Treatment Project Execution Plan'' (PEP).

  19. Groundwater-quality data in the northern Coast Ranges study unit, 2009: Results from the California GAMA Program

    USGS Publications Warehouse

    Mathany, Timothy M.; Dawson, Barbara J.; Shelton, Jennifer L.; Belitz, Kenneth

    2011-01-01

    This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, untreated groundwater typically is treated, disinfected, and (or) blended with other waters to maintain water quality. Regulatory benchmarks apply to water that is served to the consumer, not to untreated groundwater. However, to provide some context for the results, concentrations of constituents measured in the untreated groundwa

  20. Compilation of ground-water level measurements, obtained by the United States Geological Survey in Puerto Rico, 1958-1985

    USGS Publications Warehouse

    Torres-Gonzalez, Sigfredo

    1991-01-01

    A digital compilation of the groundwater levels in Puerto Rico was prepared as part of the Caribbean Islands Regional Aquifers System Analysis program. Of special interest are the groundwater levels measurements obtained on a routine basis at wells located in the different aquifer regions or aquifer zones. Data from 181 observation wells were entered in the computer data base. The data base includes the following: name, latitude and longitude coordinates, owner, diameter, depth, station identification, local number, aquifer area or region, period of record, construction date, earliest groundwater level reported, and groundwater level fluctuations for various time periods between 1958 and 1985. Data showing conditions under which groundwater level measurements may have been affected by (1) pumping of the well, (2) by a nearby pumping well (3) a specific method by which the groundwater level was determined, (4) whether the well was recently pumped, and (5) when recorded, the lowest water level are also indicated. The summarized information is available in printed format on a yearly basis as part of the Water Resources Data Publication series. (USGS)

  1. DEMONSTRATION OF THE HIPOX ADVANCED OXIDATION TECHNOLOGY FOR THE TREATMENT OF MTBE-CONTAMINATED GROUNDWATER

    EPA Science Inventory

    The HiPOx technology is an advanced oxidation process that incorporates high-precision delivery of ozone and hydrogen peroxide to chemically destroy organic contaminants with the promise of minimizing bromate formation. A MTBE-contaminated groundwater from the Ventura County Nava...

  2. Surface altered zeolites as permeable barriers for in situ treatment of contaminated groundwater

    SciTech Connect

    1996-11-01

    The authors characterized surfactant-modified zeolite (SMZ) for its ability to sorb organic and inorganic contaminants from water. The ultimate objective is to use SMZ as a permeable barrier to prevent migration of contaminants in groundwater. This report summarizes results under Phase 1 of a three-phase project leading to a full-scale field demonstration of SMZ permeable- barrier technology.

  3. Field Treatment of MTBE-Contaiminated Groundwater Using Ozone/UV Oxidation

    EPA Science Inventory

    Methyl-tertiary butyl ether (MTBE) is often found in groundwater as a result of gasoline spills and leaking underground storage tanks. An extrapolation of occurrence data in 2008 estimated at least one detection of MTBE in approximately 165 small and large public water systems se...

  4. SURFACE-ALTERED ZEOLITES AS PERMEABLE BARRIERS FOR IN SITU TREATMENT OF CONTAMINATED GROUNDWATER

    SciTech Connect

    Robert S. Bowman; Zhaohui Li; Stephen J. Roy; Todd Burt; Timothy L. Johnson; Richard L. Johnson

    1999-08-30

    The overall objective of this effort is to develop and test a zeolite-based permeable barrier system for containing and remediating contaminated groundwater. The projected product is an engineered and tested permeable barrier system that can be adopted by the commercial sector.

  5. DEMONSTRATION OF THE HIPOX ADVANCED OXIDATION TECHNOLOGY FOR THE TREATMENT OF MTBE-CONTAMINATED GROUNDWATER

    EPA Science Inventory

    The HiPOx technology is an advanced oxidation process that incorporates high-precision delivery of ozone and hydrogen peroxide to chemically destroy organic contaminants with the promise of minimizing bromate formation. A MTBE-contaminated groundwater from the Ventura County Nav...

  6. Remedial Investigation work plan for Bear Creek Valley Operable Unit 4 (shallow groundwater in Bear Creek Valley) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    SciTech Connect

    Not Available

    1993-09-01

    To effectively evaluate the cumulative impact of releases from multiple sources of contamination, a structured approach has been adopted for Oak Ridge Reservation (ORR) based on studies of the groundwater and surface water separate from studies of the sources. Based on the realization of the complexity of the hydrogeologic regime of the ORR, together with the fact that there are numerous sources contributing to groundwater contamination within a geographical area, it was agreed that more timely investigations, at perhaps less cost, could be achieved by separating the sources of contamination from the groundwater and surface water for investigation and remediation. The result will be more immediate attention [Records of Decision (RODS) for interim measures or removal actions] for the source Operable Units (OUs) while longer-term remediation investigations continue for the hydrogeologic regime`s, which are labeled as integrator OUs. This Remedial Investigation work plan contains summaries of geographical, historical, operational, geological, and hydrological information specific to the unit. Taking advantage of the historical data base and ongoing monitoring activities and applying the observational approach to focus data gathering activities will allow the Feasibility Study to evaluate all probable or likely alternatives.

  7. Remedial investigation work plan for Bear Creek Valley Operable Unit 4 (shallow groundwater in Bear Creek Valley) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    SciTech Connect

    Not Available

    1993-07-01

    To effectively evaluate the cumulative impact of releases from multiple sources of contamination, a structured approach has been adopted for Oak Ridge Reservation (ORR) based on studies of the groundwater and surface water separate from studies of the sources. Based on the realization of the complexity of the hydrogeologic regime of the ORR, together with the fact that there are numerous sources contributing to groundwater contamination within a geographical area, it was agreed that more timely investigations, at perhaps less cost, could be achieved by separating the sources of contamination from the groundwater and surface water for investigation and remediation. The result will be more immediate attention [Records of Decision (RODs) for interim measures or removal actions] for the source Operable Units (OUs) while longer-term remediation investigations continue for the hydrogeologic regimes, which are labeled as integrator OUs. This remedial investigation work plan contains summaries of geographical, historical, operational, geological, and hydrological information specific to the unit. Taking advantage of the historical data base and ongoing monitoring activities and applying the observational approach to focus data gathering activities will allow the feasibility study to evaluate all probable or likely alternatives.

  8. Perfluoroalkyl acids in municipal landfill leachates from China: Occurrence, fate during leachate treatment and potential impact on groundwater.

    PubMed

    Yan, Hong; Cousins, Ian T; Zhang, Chaojie; Zhou, Qi

    2015-08-15

    Raw and treated landfill leachate samples were collected from 5 municipal landfill sites in China to measure the concentrations and contamination profile of perfluoroalkyl acids (PFAAs) in leachate during different steps of treatment. The total concentration of PFAAs (∑PFAAs) ranged from 7280 to 292,000 ng L(-1) in raw leachate and from 98.4 to 282,000 ng L(-1) in treated leachate. The dominant compounds measured were PFOA (mean contribution 28.8% and 36.8% in raw and treated leachate, respectively) and PFBS (26.1% and 40.8% in raw and treated leachate, respectively). A calculation of mass flows during the leachate treatment processes showed that the fate of individual PFAAs was substance and treatment-specific. The Chinese national leakage of ∑PFAAs to groundwater from landfill leachate was estimated to be 3110 kg year(-1), which is a significant environmental release that is potentially threatening the sustainable use of groundwater as a drinking water source. PMID:25889541

  9. In situ treatment of arsenic contaminated groundwater by aquifer iron coating: Experimental Study

    SciTech Connect

    Xie, Xianjun; Wang, Yanxin; Pi, Kunfu; Liu, Chongxuan; Li, Junxia; Liu, Yaqing; Wang, Zhiqiang; Duan, Mengyu

    2015-09-15

    In situ arsenic removal from groundwater by an iron coating method has great potential to be a cost effective and simple groundwater remediation technique, especially in rural and remote areas where groundwater is used as the main source of drinking water. The in situ arsenic removal technique was first optimized by simulating arsenic removal in various quartz sand columns under anoxic conditions., Its effectiveness was then evaluated in an actual high-arsenic groundwater environment. The mechanism of arsenic removal by the iron coating was investigated under different conditions using scanning electron microscopy (SEM)/X-ray absorption spectroscopy, an electron microprobe, and Fourier transformation infrared spectroscopy. A 4-step alternative cycle aquifer iron coating method was developed. A continuous injection of 5 mmol/L FeSO4 and 2.5 mmol/L NaClO for 96 hours can create a uniform coating of crystalline goethite on the surface of quartz sand in the columns without causing clogging. At a flow rate of 0.45 cm/min of the injection reagents (vi), the time for arsenic (as Na2HAsO4) to pass through the iron-coated quartz sand column was approximately 35 hours, which was much longer than that for tracer fluorescein sodium (approximately 2 hours). The retardation factor of arsenic was 23, and its adsorption capacity was 0.11 mol As per mol Fe, leading to an excellent arsenic removal. In situ arsenic removal from groundwater in an aquifer was achieved by simultaneous injections of As (V) and Fe (II) reagents. When the arsenic content in the groundwater was 233 μg/L, the aqueous phase arsenic was completely removed with an arsenic adsorption of 0.05 mol As per mol Fe. Arsenic fixation resulted from a process of adsorption/co-precipitation, in which arsenic and iron likely formed the arsenic-bearing iron mineral phases with poor crystallinity by way of bidentate binuclear complexes. Thus, the high arsenic removal efficiency of the technique likely resulted from the

  10. In situ treatment of arsenic contaminated groundwater by aquifer iron coating: Experimental study.

    PubMed

    Xie, Xianjun; Wang, Yanxin; Pi, Kunfu; Liu, Chongxuan; Li, Junxia; Liu, Yaqing; Wang, Zhiqiang; Duan, Mengyu

    2015-09-15

    In situ arsenic removal from groundwater by an aquifer iron coating method has great potential to be a cost effective and simple groundwater remediation technology, especially in rural and remote areas where groundwater is used as the main water source for drinking. The in situ arsenic removal technology was first optimized by simulating arsenic removal in various quartz sand columns under anoxic conditions. The effectiveness was then evaluated in an actual high-arsenic groundwater environment. The arsenic removal mechanism by the coated iron oxide/hydroxide was investigated under different conditions using scanning electron microscopy (SEM)/X-ray absorption spectroscopy, electron probe microanalysis, and Fourier transformation infrared spectroscopy. Aquifer iron coating method was developed via a 4-step alternating injection of oxidant, iron salt and oxygen-free water. A continuous injection of 5.0 mmol/L FeSO4 and 2.5 mmol/L NaClO for 96 h can form a uniform goethite coating on the surface of quartz sand without causing clogging. At a flow rate of 7.2 mL/min of the injection reagents, arsenic (as Na2HAsO4) and tracer fluorescein sodium to pass through the iron-coated quartz sand column were approximately at 126 and 7 column pore volumes, respectively. The retardation factor of arsenic was 23.0, and the adsorption capacity was 0.11 mol As per mol Fe. In situ arsenic removal from groundwater in an aquifer was achieved by simultaneous injections of As(V) and Fe(II) reagents. Arsenic fixation resulted from a process of adsorption/co-precipitation with fine goethite particles by way of bidentate binuclear complexes. Therefore, the study results indicate that the high arsenic removal efficiency of the in situ aquifer iron coating technology likely resulted from the expanded specific surface area of the small goethite particles, which enhanced arsenic sorption capability and/or from co-precipitation of arsenic on the surface of goethite particles. PMID:25956146

  11. Studies on the integration of nanofiltration and soil treatment for municipal effluent reclamation as a groundwater supplement.

    PubMed

    Linlin, Wu; Xuan, Zhao; Meng, Zhang

    2010-01-01

    Water shortage leads to increasing attention to artificial groundwater recharge by reclaimed water. An injection well is the most common recharge approach. In this paper, a new kind of integrated technology-short-term vadose soil treatment followed by nanofiltration-is recommended as pretreatment for artificial groundwater recharge by an injection well. Laboratory-scale experiments demonstrate that the short-term vadose soil can remove approximately 30% of the total dissolved organic carbon (DOC) content and 40% of dissolved organic matter with a molecular weight less than 1 kDa. As a compensatory process of soil treatment, nanofiltration offers a favorable desalination and additional organics removal. The removal efficiencies for total dissolved solids and conductivity amount to 45 and 48%, respectively. The residual DOC in the final effluent is below 1.0 mg/L. In addition, short-term vadose soil offers effective elimination of aromatic protein-like and polysaccharide-like substances, which are detected as components of the membrane foulant. PMID:20112534

  12. Water quality and geochemistry evaluation of groundwater upstream and downstream of the Khirbet Al-Samra wastewater treatment plant/Jordan

    NASA Astrophysics Data System (ADS)

    Bajjali, William; Al-Hadidi, Kheir; Ismail, Ma'mmon

    2015-01-01

    Groundwater in the northeastern Amman-Zarqa basin is an important source of water for irrigation. The quality and quantity of water has deteriorated due to mismanagement and misunderstanding of the hydrogeological system. Overexploitation of groundwater resources upstream of the Khirbet Al-Samra wastewater treatment plant (KSWTP) has lowered the water table 43 m since the beginning of groundwater development in 1968. Heavy pumping of groundwater downstream of KSWTP has not dropped the water level due to constant recharge from the Zarqa river bed. The water level of groundwater is rising continuously at a rate of 20 cm per year since building the KSWTP in 1985. Groundwater salinity has also shifted the quality of the aquifer from fresh to brackish. Continual irrigation from the groundwater upstream of KSWTP dissolves accumulated salt from the soil formed by evaporation, and the contaminated water infiltrates back to the aquifer, thereby increasing both salt and nitrate concentrations. The intense irrigation from the reclaimed water downstream of KSWTP and leakage of treated wastewater from the Zarqa River to the shallow groundwater is a secondary source of salt and nitrates. The isotopic composition of groundwater varies over a wide range and is associated with the meteoric water line affected by Mediterranean Sea air moisture. The isotopic composition of groundwater is represented by evaporation line (EL) with a low slope of 3.6. The enrichment of groundwater in δ18O and δD is attributed mainly to the two processes of evaporation before infiltration of return flow and mixing of different types of water in KSWTP originating from different aquifers. The EL starts from a location more depleted than the weighted mean value of the Amman rainfall station on the Eastern Meteoric Water Line indicating that the recharge took place under the climate regime prevailing today in Jordan and the recharge of the groundwater originates from a greater elevation than that of the

  13. New Pump and Treat Facility Remedial Action Work Plan for Test Area North (TAN) Final Groundwater Remediation, Operable Unit 1-07B

    SciTech Connect

    L. O. Nelson

    2003-09-01

    This operations and maintenance plan supports the New Pump and Treat Facility (NPTF) remedial action work plan and identifies the approach and requirements for the operations and maintenance activities specific to the final medical zone treatment remedy. The NPTF provides the treatment system necessary to remediate the medical zone portion of the OU 1-07B contaminated groundwater plume. Design and construction of the New Pump and Treat Facility is addressed in the NPTF remedial action work plan. The scope of this operation and maintenance plan includes facility operations and maintenance, remedy five-year reviews, and the final operations and maintenance report for the NPTF.

  14. Radioactive Water Treatment at a United States Environmental Protection Agency Superfund Site - 12322

    SciTech Connect

    Beckman, John C.

    2012-07-01

    A water treatment system at a United States Environmental Protection Agency (USEPA) Superfund site impacted by radiological contaminants is used to treat water entering the site. The United States Army Corps of Engineers (USACE) is actively managing the remedial action for the USEPA using contracts to support the multiple activities on site. The site is where former gas mantle production facilities operated around the turn of the century. The manufacturing facilities used thorium ores to develop the mantles and disposed of off-specification mantles and ore residuals in the surrounding areas. During Site remedial actions, both groundwater and surface water comes into contact with contaminated soils and must be collected and treated at an on-site treatment facility. The radionuclides thorium and radium with associated progeny are the main concern for treatment. Suspended solids, volatile organic compounds, and select metals are also monitored during water treatment. The water treatment process begins were water is pumped to a collection tank where debris and grit settle out. Stored water is pumped to a coagulant tank containing poly-aluminum chloride to collect dissolved solids. The water passes into a reaction tube where aspirated air is added or reagent added to remove Volatile Organic Compounds (VOC'S) by mass transfer and convert dissolved iron to a solid. The water enters the flocculent polymer tank to drop solids out. The flocculated water overflows to a fluidized bed contact chamber to increase precipitation. Flocculation is where colloids of material drop out of suspension and settle. The settled solids are periodically removed and disposed of as radioactive waste. The water is passed through filters and an ion exchange process to extract the radionuclides. Several million liters of water are processed each year from two water treatment plants servicing different areas of the remediation site. Ion exchange resin and filter material are periodically replaced

  15. An evaluation of the impact of recent flooding on the operation of a groundwater extraction and treatment system at a Superfund Site

    SciTech Connect

    Gavett, K.L.; Fiore, M.J.; Meyer, E.J.

    1994-12-31

    A groundwater extraction and treatment system was installed in 1987 at the Des Moines TCE Superfund Site. The purpose of the system is to prevent groundwater contaminated with chlorinated volatile organic compounds (VOCs) from migrating toward an infiltration gallery system which supplies drinking water to the City of Des Moines, Iowa. The extraction system was not operating for a three week period in July and August when the system was flooded by the nearby Raccoon collected as part of a monitoring program have been s the affect of flooding on the operation of the system. Records indicate that the flood did not have a long-term impact on the Performance of the system. An examination of groundwater levels show that groundwater elevations receded quickly after the flood, similar to patterns observed after other periods of heavy precipitation. In fact, data collected nine weeks after the extraction system was returned to service indicate that the system continues to meet its containment objective. Water quality records indicate that the affect of the 1993 flood was similar to trends Observed after earlier periods of heavy precipitation. Trichloroethene concentrations in the treatment system influent and in wells located in the vicinity of suspected source areas increased as a result of rising groundwater levels, and infiltration through residual contamination in the unsaturated zone. Groundwater quality in areas beyond suspected source areas does not appear to have been affected by the 1993 flood.

  16. Data Quality Objectives Summary Report - Designing a Groundwater Monitoring Network for the 200-BP-5 and 200-PO-1 Operable Units

    SciTech Connect

    Thornton, Edward C.; Lindberg, Jon W.

    2002-09-30

    This document presents the results of a series of interviews held with technical, management, and regulatory staff to determine the groundwater data quality objectives (DQOs) for monitoring activities associated with the 200-BP-5 and 200-PO-1 operable units located in the Hanford Site 200 East Area. This assessment is needed to address changing contaminant plume conditions (e.g., plume migration) and to ensure that monitoring activities meet the requirements for performance monitoring as prescribed by the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), Resource Conservation and Recovery Act of 1976 (RCRA) past practice, and Atomic Energy Act of 1954 (AEA) regulatory requirements and orders.

  17. Factors Affecting Temporal Variability of Arsenic in Groundwater Used for Drinking Water Supply in the United States

    EPA Science Inventory

    The occurrence of arsenic in groundwater is a recognized environmental hazard with worldwide importance and much effort has been focused on surveying and predicting where arsenic occurs. Temporal variability is one aspect of this environmental hazard that has until recently recei...

  18. Occurrence of fungicides and other pesticides in surface water, groundwater, and sediment from three targeted-use areas in the United States, 2009

    USGS Publications Warehouse

    Orlando, James L.; Smalling, Kelly L.; Reilly, Timothy J.; Boehlke, Adam; Meyer, Michael T.; Kuivila, Kathryn M.

    2013-01-01

    Surface-water, groundwater, and suspended- and bedsediment samples were collected in three targeted-use areas in the United States where potatoes were grown during 2009 and analyzed for an extensive suite of fungicides and other pesticides by gas chromatograph/mass spectrometry and liquid chromatography with tandem mass spectrometry. Fungicides were detected in all environmental matrices sampled during the study. The most frequently detected fungicides were azoxystrobin, boscalid, chlorothalonil, and pyraclostrobin. Other pesticides that were detected frequently included amino phosphonic acid (AMPA), atrazine, metolaclor, and the organochlorine insecticide p,p’-DDT and its degradates p,p’-DDD and p,p’-DDE. A greater number of pesticides were detected in surface water relative to the other environmental matrices sampled, and at least one pesticide was detected in 62 of the 63 surfacewater samples. The greatest numbers of pesticides and the maximum observed concentrations for most pesticides were measured in surface-water samples from Idaho. In eight surface- water samples (six from Idaho and two from Wisconsin), concentrations of bifenthrin, metolachlor, or malathion exceeded U.S. Environmental Protection Agency freshwater aquatic-life benchmarks for chronic toxicity to invertebrates. Thirteen pesticides, including seven fungicides, were detected in groundwater samples. Shallow groundwater samples collected beneath recently harvested potato fields contained more pesticides and had higher concentrations of pesticides than samples collected from other groundwater sources sampled during the study. Generally, pesticide concentrations were lower in groundwater samples than in surfacewater or sediment samples, with the exception of the fungicide boscalid, which was found to have its highest concentration in a shallow groundwater sample collected in Wisconsin. Thirteen pesticides, including four fungicides, were detected in suspended-sediment samples. The most

  19. Regulatory and Technical Issues Concerning the Detection and Treatment of NDMA-Contaminated Groundwater at NASA WSTF

    NASA Technical Reports Server (NTRS)

    Wiebe, D. T.; Zigmond, M. J.; Tufts, C. A.

    2002-01-01

    The National Aeronautics and Space Administration (NASA) White Sands Test Facility (WSTF) was established in 1963 primarily to provide rocket engine testing services for several NASA programs. The groundwater underlying the site has been contaminated as a result of historical operations. Groundwater contaminants include several volatile organic compounds (VOCs) and two semi-volatile compounds: N-nitrosodimethylamine (NDMA) and N-nitrodimethylamine (DMN). This paper discusses some of the technical, analytical, regulatory, and health risk issues associated with the contaminant plume. The plume has moved approximately 2.5 miles downgradient of the facility industrial boundary, with evidence of continued migration. As a result, NASA has proposed a pump and treat system using air strippers and ultraviolet (UV) oxidation to stabilize future movement of the contaminant plume. The system has been designed to treat 1,076 gallons (4,073 liters) per minute, with provisions for future expansion. The UV oxidation process was selected to treat NDMA-contaminated groundwater based on successes at other NDMA-contaminated sites. Bench- and pilot-scale testing of WSTF groundwater confirmed the ability of UV oxidation to destroy NDMA and generated sufficient data to design the proposed full-scale treatment system. NDMA is acutely toxic and is a probable human carcinogen. EPA-recommended health risk criteria for the residential consumption of NDMA/DMN-contaminated groundwater was used to determine that a 1.0 x 10(exp -6) excess cancer risk corresponds to 1.7 parts per trillion (ppt). EPA analytical methods are unable to detect NDMA and DMN in the low ppt range. EPA's current Appendix IX analytical method used to screen for NDMA, Method 8270, can detect NDMA only at levels that are orders of magnitude greater than the recommended health risk level. Additionally, EPA Method 607, the most sensitive EPA approved method, has a detection limit of 150 ppt. This corresponds to an excess cancer

  20. Groundwater geochemical and selected volatile organic compound data, Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington, June and September 2014

    USGS Publications Warehouse

    Huffman, Raegan L.

    2015-01-01

    Previous investigations indicate that concentrations of chlorinated volatile organic compounds (CVOCs) are substantial in groundwater beneath the 9-acre former landfill at Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington. The U.S. Geological Survey has continued to monitor groundwater geochemistry to ensure that conditions remain favorable for contaminant biodegradation at the site. This report presents groundwater geochemical and selected CVOC data collected at Operable Unit 1 by the U.S. Geological Survey during June 23–25 and September 4, 2014, in support of long-term monitoring for natural attenuation. Groundwater samples were collected from 13 wells and 9 piezometers, as well as from 10 shallow groundwater passive-diffusion sampling sites in the nearby marsh. Samples from all wells and piezometers were analyzed for oxidation-reduction (redox) sensitive constituents and dissolved gases. Samples from all piezometers and four wells also were analyzed for CVOCs, as were all samples from the passive-diffusion sampling sites. In 2014, concentrations of redox-sensitive constituents measured at all wells and piezometers were consistent with those measured in previous years, with dissolved oxygen concentrations all less than 1 milligram per liter; little to no detectable nitrate; abundant dissolved manganese, iron, and methane; and commonly detected sulfide. In the upper aquifer of the northern plantation in 2014, CVOC concentrations at all piezometers were similar to those measured in previous years, and concentrations of the reductive dechlorination byproducts ethane and ethene were slightly lower or the same as concentrations measured in 2013. In the upper aquifer of the southern plantation, CVOC concentrations measured in piezometers during 2014 continued to be variable as in previous years, often high, and reductive dechlorination byproducts were detected in one of the three wells and in all but two piezometers. Beneath the marsh

  1. Groundwater geochemical and selected volatile organic compound data, Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington, June and October 2012

    USGS Publications Warehouse

    Huffman, R.L.

    2013-01-01

    Previous investigations indicate that concentrations of chlorinated volatile organic compounds are substantial in groundwater beneath the 9-acre former landfill at Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington. The U.S. Geological Survey has continued to monitor groundwater geochemistry to ensure that conditions remain favorable for contaminant biodegradation as specified in the Record of Decision for the site. This report presents groundwater geochemical and selected chlorinated volatile organic compound data collected at Operable Unit 1 by the U.S. Geological Survey during June and October 2012, in support of long-term monitoring for natural attenuation. Groundwater samples were collected from 13 wells and 9 piezometers, as well as from 10 shallow groundwater passive-diffusion sampling sites in the nearby marsh. Samples from all wells and piezometers were analyzed for oxidation-reduction (redox) sensitive constituents and dissolved gases. Samples from all piezometers also were analyzed for chlorinated volatile organic compounds, as were all samples from the passive-diffusion sampling sites. In 2012, concentrations of redox-sensitive constituents measured at all wells and piezometers were consistent with those measured in previous years, with dissolved oxygen concentrations all at 0.4 milligram per liter or less; little to no detectable nitrate; abundant dissolved manganese, iron, and methane; and commonly detected sulfide. In the upper aquifer of the northern plantation in 2012, chlorinated volatile organic compound (CVOC) concentrations at all piezometers were similar to those measured in previous years, and concentrations of the reductive dechlorination byproducts ethane and ethene were slightly higher or the same as concentrations measured in 2011. In the upper aquifer of the southern plantation, CVOC concentrations measured in piezometers during 2012 continued to be extremely variable as in previous years, and often very high

  2. Ground-water surface-water interactions and long-term change in riverine riparian vegetation in the southwestern United States

    USGS Publications Warehouse

    Webb, R.H.; Leake, S.A.

    2006-01-01

    Riverine riparian vegetation has changed throughout the southwestern United States, prompting concern about losses of habitat and biodiversity. Woody riparian vegetation grows in a variety of geomorphic settings ranging from bedrock-lined channels to perennial streams crossing deep alluvium and is dependent on interaction between ground-water and surface-water resources. Historically, few reaches in Arizona, southern Utah, or eastern California below 1530 m elevation had closed gallery forests of cottonwood and willow; instead, many alluvial reaches that now support riparian gallery forests once had marshy grasslands and most bedrock canyons were essentially barren. Repeat photography using more than 3000 historical images of rivers indicates that riparian vegetation has increased over much of the region. These increases appear to be related to several factors, notably the reduction in beaver populations by trappers in the 19th century, downcutting of arroyos that drained alluvial aquifers between 1880 and 1910, the frequent recurrence of winter floods during discrete periods of the 20th century, an increased growing season, and stable ground-water levels. Reductions in riparian vegetation result from agricultural clearing, excessive ground-water use, complete flow diversion, and impoundment of reservoirs. Elimination of riparian vegetation occurs either where high ground-water use lowers the water table below the rooting depth of riparian species, where base flow is completely diverted, or both. We illustrate regional changes using case histories of the San Pedro and Santa Cruz Rivers, which are adjacent watersheds in southern Arizona with long histories of water development and different trajectories of change in riparian vegetation.

  3. A Hydrostratigraphic System for Modeling Groundwater Flow and Radionuclide Migration at the Corrective Action Unit Scale, Nevada Test Site and Surrounding Areas, Clark, Lincoln, and Nye Counties, Nevada

    SciTech Connect

    Prothro, Lance; Drellack Jr., Sigmund; Mercadante, Jennifer

    2009-01-31

    Underground Test Area (UGTA) corrective action unit (CAU) groundwater flow and contaminant transport models of the Nevada Test Site (NTS) and vicinity are built upon hydrostratigraphic framework models (HFMs) that utilize the hydrostratigraphic unit (HSU) as the fundamental modeling component. The delineation and three-dimensional (3-D) modeling of HSUs within the highly complex geologic terrain that is the NTS requires a hydrostratigraphic system that is internally consistent, yet flexible enough to account for overlapping model areas, varied geologic terrain, and the development of multiple alternative HFMs. The UGTA CAU-scale hydrostratigraphic system builds on more than 50 years of geologic and hydrologic work in the NTS region. It includes 76 HSUs developed from nearly 300 stratigraphic units that span more than 570 million years of geologic time, and includes rock units as diverse as marine carbonate and siliciclastic rocks, granitic intrusives, rhyolitic lavas and ash-flow tuffs, and alluvial valley-fill deposits. The UGTA CAU-scale hydrostratigraphic system uses a geology-based approach and two-level classification scheme. The first, or lowest, level of the hydrostratigraphic system is the hydrogeologic unit (HGU). Rocks in a model area are first classified as one of ten HGUs based on the rock’s ability to transmit groundwater (i.e., nature of their porosity and permeability), which at the NTS is mainly a function of the rock’s primary lithology, type and degree of postdepositional alteration, and propensity to fracture. The second, or highest, level within the UGTA CAU-scale hydrostratigraphic system is the HSU, which is the fundamental mapping/modeling unit within UGTA CAU-scale HFMs. HSUs are 3-D bodies that are represented in the finite element mesh for the UGTA groundwater modeling process. HSUs are defined systematically by stratigraphically organizing HGUs of similar character into larger HSUs designations. The careful integration of

  4. Disparities in access to effective treatment for infertility in the United States: an Ethics Committee opinion.

    PubMed

    2015-11-01

    In the United States, economic, racial, ethnic, geographic, and other disparities exist in access to fertility treatment and in treatment outcomes. This opinion examines the factors that contribute to these disparities and proposes actions to address them. PMID:26364838

  5. Using Work Breakdown Structure Models to Develop Unit Treatment Costs

    EPA Science Inventory

    This article presents a new cost modeling approach called work breakdown structure (WBS), designed to develop unit costs for drinking water technologies. WBS involves breaking the technology into its discrete components for the purposes of estimating unit costs. The article dem...

  6. A Hydrostrat Model and Alternatives for Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 99: Rainer Mesa-Shoshone Mountain, Nye County, Nevada

    SciTech Connect

    NSTec Geotechnical Sciences Group

    2007-03-01

    The three-dimensional hydrostratigraphic framework model for the Rainier Mesa-Shoshone Mountain Corrective Action Unit was completed in Fiscal Year 2006. The model extends from eastern Pahute Mesa in the north to Mid Valley in the south and centers on the former nuclear testing areas at Rainier Mesa, Aqueduct Mesa, and Shoshone Mountain. The model area also includes an overlap with the existing Underground Test Area Corrective Action Unit models for Yucca Flat and Pahute Mesa. The model area is geologically diverse and includes un-extended yet highly deformed Paleozoic terrain and high volcanic mesas between the Yucca Flat extensional basin on the east and caldera complexes of the Southwestern Nevada Volcanic Field on the west. The area also includes a hydrologic divide between two groundwater sub-basins of the Death Valley regional flow system. A diverse set of geological and geophysical data collected over the past 50 years was used to develop a structural model and hydrostratigraphic system for the model area. Three deep characterization wells, a magnetotelluric survey, and reprocessed gravity data were acquired specifically for this modeling initiative. These data and associated interpretive products were integrated using EarthVision{reg_sign} software to develop the three-dimensional hydrostratigraphic framework model. Crucial steps in the model building process included establishing a fault model, developing a hydrostratigraphic scheme, compiling a drill-hole database, and constructing detailed geologic and hydrostratigraphic cross sections and subsurface maps. The more than 100 stratigraphic units in the model area were grouped into 43 hydrostratigraphic units based on each unit's propensity toward aquifer or aquitard characteristics. The authors organized the volcanic units in the model area into 35 hydrostratigraphic units that include 16 aquifers, 12 confining units, 2 composite units (a mixture of aquifer and confining units), and 5 intrusive confining

  7. Performance assessment of a zeolite treatment wall for removing Sr-90 from groundwater.

    PubMed

    Rabideau, Alan J; Van Benschoten, John; Patel, Amita; Bandilla, Karl

    2005-09-01

    Laboratory and modeling studies were conducted to assess the potential performance of a permeable reactive barrier constructed of a natural zeolite material at the West Valley Demonstration Project in western New York State. The results of laboratory column tests indicated that the barrier material would be effective at removing strontium from groundwater under natural gradient conditions. Two one-dimensional contaminant transport models were developed to interpret the data. A single-solute retardation factor model provided good agreement with the column test data, but time-consuming extraction and analysis of the zeolite material was required to parameterize the model. A preliminary six-solute model was also developed based on the assumption of competitive cation exchange as the primary removal mechanism. Both models yielded similar predictions of the long-term performance of the barrier, but the cation exchange model predicted higher effluent concentrations during the first 1000 pore volumes of operation. The cation exchange framework has several advantages, including the ability to calibrate the model using only data from column effluent samples, and the ability to account for site-specific differences in the groundwater cation composition. However, additional laboratory work is needed to develop a suitably robust model. PMID:16061306

  8. Contaminated Groundwater N flux to Surface Waters from Biosolid Waste Application Fields at a Waste Water Treatment Facility

    NASA Astrophysics Data System (ADS)

    Showers, W. J.; Fountain, M.; Fountain, J. C.

    2006-05-01

    Biosolids have been land applied at the Neuse River Waste Water Treatment Plant (NRWWTP) since 1980. The long biosolid application history at this site has resulted in a build up of nitrate in the ground water beneath the Waste Application Fields (WAFs). We have used an innovative river monitoring system that measures in situ nitrate concentrations and discharge above and below the plant to determine the amount of nitrate gained in the reach from the WAFs. The nitrogen and oxygen isotopic composition of nitrate in the WAF groundwater indicates that 18% of the monitoring wells are impacted by fertilizer N, 57% of the wells are impacted by biosolid N, 22% of the wells are affected by denitrification, and one well is impacted by A.D.N. The net daily contribution of surface / ground water and nitrate to the reach was calculated from the sum of the flux into the reach at the upper RiverNet station plus the plant discharge minus the flux out of the reach at the lower RiverNet station. The difference between the flux into the reach and plant discharge minus the flux out of the reach is termed the non-point source gain (NPS gain). The NPS gain could come from groundwater and/or surface drainage additions to the reach. On an annual basis, daily integrated NPS nitrate gains were ~70,000 kg in year 2004 and ~27,900 kg in 2005. This represents an average over the two year period of ~12% of the total nitrate flux out of the reach and 43% of the nitrate discharged from the plant. During the past year groundwater wells were installed in the river riparian buffer and N Flux was measured in a surface water drainage in the WAF. The results indicate that N is not migrating through the shallow groundwater, and most of the NPS gains in the reach can come from surface drainages which have nitrate concentrations of 30-80 mg/l. Over the next year wetlands will be reconstructed in the surface drainages to attenuate the N flux and protect river water quality.

  9. Groundwater contamination field methods

    NASA Astrophysics Data System (ADS)

    Johnson, Ivan

    Half of the drinking water in the United States comes from groundwater; 75% of the nation's cities obtain all or part of their supplies from groundwater; and the rural areas are 95% dependent upon groundwater. Therefore it is imperative that every possible precaution be taken to protect the purity of the groundwater.Because of the increasing interest in prevention of groundwater contamination and the need for nationally recognized methods for investigation of contamination, a symposium entitled “Field Methods for Groundwater Contamination Studies and Their Standardization” was held February 2-7, 1986, in Cocoa Beach, Fla. The symposium was sponsored and organized by the American Society for Testing and Materials (ASTM) Committee D18 on Soil and Rock and Committee D19 on Water. Gene Collins of the National Institute for Petroleum and Energy Research (Bartlesville, Okla.) was symposium chair, and Ivan Johnson (A. Ivan Johnson, Inc., Consulting, Arvada, Colo.) was vice chair.

  10. [Guidelines for treatment of pneumonia in intensive care units].

    PubMed

    Emmi, V

    2005-01-01

    Patients affected by pneumonia can be admitted in Intensive Care Units (ICUs) independently by the setting where the infection has been acquired (community, hospital, long-term care facilities); even more frequently pneumonia can develop in patients already hospitalized in ICU especially in those requiring mechanical ventilation for different reasons. Within the severe community acquired pneumonia requiring admission in ICU, the most frequently responsible micro-organisms are mainly represented by Streptococcus pneumoniae, but also by Legionella and Haemophilus. Pseudomonas aeruginona, anyway, cannot be excluded. The most recent Canadian and American guidelines for treatment of the above mentioned infections suggest the use of a combination therapy with beta-lactams (ceftriaxone, cefotaxime, ampicillin/sulbactam, piperacillin/tazobactam) and a new generation macrolide or respiratory fluoroquinolone. In case of allergy to beta-lactams, the association fluoroquinolone-clindamycin should be preferred. Whenever a Pseudomonas etiology is suspected because of the presence of risk factors such as COPD, cystic fibrosis, bronchiectasis, previous and/or frequent therapies with antibiotics and/or steroids, the same guidelines suggest the use of an anti-pseudomonas beta-lactam (such as piperacillin/tazobactam, carbapenems, cefepime) associated with an anti-pseudomonas fluoroquinolone (high doses ciprofloxacin). An anti-pseudomonas beta-lactam plus an aminoglycoside or aminoglicosyde plus fluoroquinolone can be an alternative. Early onset Hospital Acquired Pneumonia (HAP) and early onset Ventilator Associated Pneumonia (VAP) in patients without risk factors for multi-resistant etiological agents are generally sustained by S. pneumoniae, H. influenzae, methicillin-susceptible Staphylocccus aureus e Gram negative enteric rods. These infections can be treated with one of the following antibiotics: ceftriaxone or fluoroquinolones (moxifloxacin or ciprofloxacin or levofloxacin) or

  11. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Estimated Mean Annual Natural Groundwater Recharge, 2002

    USGS Publications Warehouse

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the mean annual natural groundwater recharge, in millimeters, compiled for every MRB_E2RF1catchment of selected Major River Basins (MRBs, Crawford and others, 2006). The source data set is Estimated Mean Annual Natural Ground-Water Recharge in the Conterminous United States (Wolock, 2003). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

  12. Biodegradation of chloroethene compounds in groundwater at Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington, 1999-2010

    USGS Publications Warehouse

    Dinicola, R.S.; Huffman, R.L.

    2012-01-01

    Flux calculations based on 2010 data indicate that 95 percent of dissolved-phase chloroethenes in the upper aquifer beneath the southern landfill were degraded before discharging to surface water. Overall, biodegradation of chloroethenes in groundwater throughout OU 1 continued through 2010, and it prevented most of the mass of dissolved-phase chloroethenes in the upper aquifer beneath the landfill from discharging to surface water.

  13. Factors affecting temporal variability of arsenic in groundwater used for drinking water supply in the United States.

    PubMed

    Ayotte, Joseph D; Belaval, Marcel; Olson, Scott A; Burow, Karen R; Flanagan, Sarah M; Hinkle, Stephen R; Lindsey, Bruce D

    2015-02-01

    The occurrence of arsenic in groundwater is a recognized environmental hazard with worldwide importance and much effort has been focused on surveying and predicting where arsenic occurs. Temporal variability is one aspect of this environmental hazard that has until recently received less attention than other aspects. For this study, we analyzed 1245 wells with two samples per well. We suggest that temporal variability, often reported as affecting very few wells, is perhaps a larger issue than it appears and has been overshadowed by datasets with large numbers of non-detect data. Although there was only a slight difference in arsenic concentration variability among samples from public and private wells (p=0.0452), the range of variability was larger for public than for private wells. Further, we relate the variability we see to geochemical factors-primarily variability in redox-but also variability in major-ion chemistry. We also show that in New England there is a weak but statistically significant indication that seasonality may have an effect on concentrations, whereby concentrations in the first two quarters of the year (January-June) are significantly lower than in the second two quarters (July-December) (p<0.0001). In the Central Valley of California, the relation of arsenic concentration to season was not statistically significant (p=0.4169). In New England, these changes appear to follow groundwater levels. It is possible that this difference in arsenic concentrations is related to groundwater level changes, pumping stresses, evapotranspiration effects, or perhaps mixing of more oxidizing, lower pH recharge water in wetter months. Focusing on the understanding the geochemical conditions in aquifers where arsenic concentrations are concerns and causes of geochemical changes in the groundwater environment may lead to a better understanding of where and by how much arsenic will vary over time. PMID:24650751

  14. Factors affecting temporal variability of arsenic in groundwater used for drinking water supply in the United States

    USGS Publications Warehouse

    Ayotte, Joseph D.; Belaval, Marcel; Olson, Scott A.; Burow, Karen R.; Flanagan, Sarah M.; Hinkle, Stephen R.; Lindsey, Bruce D.

    2014-01-01

    The occurrence of arsenic in groundwater is a recognized environmental hazard with worldwide importance and much effort has been focused on surveying and predicting where arsenic occurs. Temporal variability is one aspect of this environmental hazard that has until recently received less attention than other aspects. For this study, we analyzed 1245 wells with two samples per well. We suggest that temporal variability, often reported as affecting very few wells, is perhaps a larger issue than it appears and has been masked by datasets with large numbers of non-detect data. Although there was only a slight difference in arsenic concentration variability among samples from public and private wells (p = 0.0452), the range of variability was larger for public than for private wells. Further, we relate the variability we see to geochemical factors—primarily variability in redox—but also variability in pH and major-ion chemistry. We also show that in New England there is a weak but statistically significant indication that seasonality may have an effect on concentrations, whereby concentrations in the first two quarters of the year (January–June) are significantly lower than in the second two quarters (July–December) (p < 0.0001). In the Central Valley of California, though not statistically significant (p = 0.4169), arsenic concentration is lower in the first quarter of the year but increases in subsequent quarters. In both regions, these changes appear to follow groundwater levels. It is possible that this difference in arsenic concentrations is related to groundwater level changes, pumping stresses, evapotranspiration effects, or perhaps mixing of more oxidizing, lower pH recharge water in wetter months. Focusing on the understanding the geochemical conditions in aquifers where arsenic concentrations are concerns and causes of geochemical changes in the groundwater environment may lead to a better understanding of where and by how much arsenic will vary over

  15. How Outpatient Substance Abuse Treatment Unit Director Activities May Affect Provision of Community Outreach Services

    ERIC Educational Resources Information Center

    Chuang, Emmeline; Wells, Rebecca; Alexander, Jeffrey; Green, Sherri

    2013-01-01

    Aims: Community outreach services play an important role in infectious disease prevention and engaging drug users not currently in treatment. However, fewer than half of US substance abuse treatment units provide these services and many have little financial incentive to do so. Unit directors generally have latitude about scope of services,…

  16. Concentration data for anthropogenic organic compounds in groundwater, surface water, and finished water of selected community water systems in the United States, 2002-10

    USGS Publications Warehouse

    Carter, Janet M.; Kingsbury, James A.; Hopple, Jessica A.; Delzer, Gregory C.

    2010-01-01

    The National Water-Quality Assessment Program of the U.S. Geological Survey began implementing Source Water-Quality Assessments (SWQAs) in 2001 that focus on characterizing the quality of source water and finished water of aquifers and major rivers used by some of the larger community water systems in the United States. As used in SWQA studies, source water is the raw (ambient) water collected at the supply well before water treatment (for groundwater) or the raw (ambient) water collected from the river near the intake (for surface water), and finished water is the water that has been treated and is ready to be delivered to consumers. Finished-water samples are collected before the water enters the distribution system. The primary objective of SWQAs is to determine the occurrence of more than 250 anthropogenic organic compounds in source water used by community water systems, many of which currently are unregulated in drinking water by the U.S. Environmental Protection Agency. A secondary objective is to understand recurrence patterns in source water and determine if these patterns also occur in finished water before distribution. SWQA studies were conducted in two phases for most studies completed by 2005, and in one phase for most studies completed since 2005. Analytical results are reported for a total of 295 different anthropogenic organic compounds monitored in source-water and finished-water samples collected during 2002-10. The 295 compounds were classified according to the following 13 primary use or source groups: (1) disinfection by-products; (2) fumigant-related compounds; (3) fungicides; (4) gasoline hydrocarbons, oxygenates, and oxygenate degradates; (5) herbicides and herbicide degradates; (6) insecticides and insecticide degradates; (7) manufacturing additives; (8) organic synthesis compounds; (9) pavement- and combustion-derived compounds; (10) personal-care and domestic-use products; (11) plant- or animal-derived biochemicals; (12) refrigerants and

  17. Lab-scale tests and numerical simulations for in situ treatment of polluted groundwater.

    PubMed

    Careghini, A; Saponaro, S; Sezenna, E; Daghio, M; Franzetti, A; Gandolfi, I; Bestetti, G

    2015-04-28

    Methyl tert-butyl ether (MTBE) is used at significant percentages as an additive of unleaded gasoline. The physical-chemical properties of the substance (water solubility, soil organic carbon-water partition coefficient) cause high mobility and high concentrations in groundwater. Laboratory scale batch and column tests and mathematical modeling were performed to study the feasibility of a biobarrier (BB), that is an in situ permeable biological barrier with or without inoculation, for the remediation of MTBE and other gasoline-derived pollutants (benzene, toluene, ethylbenzene, o-xylene and m+p-xylenes, BTEXs) polluted groundwater and to estimate kinetic constants. The experimental results showed simultaneous biodegradation of MTBE and BTEXs, with similar removals in the uninoculated and the inoculated systems. Ranges for the first order kinetic removal were obtained for MTBE ((0.18±0.02)/(0.28±0.11d(-1))), B ((0.39±0.12)/(0.56±0.12d(-1))), T ((0.51±0.03)/(0.78±0.15d(-1))), E ((0.46±0.18)/(1.57±0.21d(-1))), o-X ((0.24±0.08)/(0.64±0.09d(-1))) and m+p-X ((0.20±0.04)/(1.21±0.04d(-1))). The results of the laboratory tests allowed to improve mathematical modeling in order to design a full-scale BB at a gasoline-contaminated site. PMID:25644032

  18. REMOVAL OF DBCP FROM GROUNDWATER. VOLUME 1. POE/POU TREATMENT DEVICES: INSTITUTIONAL AND JURISDICTIONAL FACTORS

    EPA Science Inventory

    The results obtained from evaluating ten GAC POE (point-of-entry) devices show that while these GAC units generally function very satisfactorily, their performance can change markedly over short periods of time.

  19. A novel conversion of the groundwater treatment sludge to magnetic particles for the adsorption of methylene blue.

    PubMed

    Zhu, Suiyi; Fang, Shuai; Huo, Mingxin; Yu, Yang; Chen, Yu; Yang, Xia; Geng, Zhi; Wang, Yi; Bian, Dejun; Huo, Hongliang

    2015-07-15

    Iron sludge, produced from filtration and backwash of groundwater treatment plant, has long been considered as a waste for landfill. In this study, iron sludge was reused to synthesize Fe3O4 magnetic particles (MPs) by using a novel solvothermal process. Iron sludge contained abundant amounts of silicon, iron, and aluminum and did not exhibit magnetic properties. After treatment for 4h, the amorphous Fe in iron sludge was transformed into magnetite Fe3O4, which could be easily separated from aqueous solution with a magnet. The prepared particles demonstrated the intrinsic properties of soft magnetic materials and could aggregate into a size of 1 μm. MPs treated for 10h exhibited excellent magnetic properties and a saturation magnetization value of 9 emu/g. The obtained particles presented the optimal adsorption of methylene blue under mild conditions, and the maximum adsorption capacity was 99.4 mg/g, which was higher than that of granular active carbon. The simple solvothermal method can be used to prepare Fe3O4 MPs from iron sludge, and the products could be applied to treatment of dyeing wastewater. PMID:25804792

  20. ADVANCES IN DRINKING WATER TREATMENT IN THE UNITED STATES

    EPA Science Inventory

    The United States drinking water public health protection goal is to provide water that meets all health-based standards to ninety-five percent of the population served by public drinking water supplies by 2005. In 2002, the level of compliance with some eighty-five health-based ...

  1. Evaluation of the importance of clay confining units on groundwater flow in alluvial basins using solute and isotope tracers: the case of Middle San Pedro Basin in southeastern Arizona (USA)

    NASA Astrophysics Data System (ADS)

    Hopkins, Candice B.; McIntosh, Jennifer C.; Eastoe, Chris; Dickinson, Jesse E.; Meixner, Thomas

    2014-06-01

    As groundwater becomes an increasingly important water resource worldwide, it is essential to understand how local geology affects groundwater quality, flowpaths and residence times. This study utilized multiple tracers to improve conceptual and numerical models of groundwater flow in the Middle San Pedro Basin in southeastern Arizona (USA) by determining recharge areas, compartmentalization of water sources, flowpaths and residence times. Ninety-five groundwater and surface-water samples were analyzed for major ion chemistry (water type and Ca/Sr ratios) and stable (18O, 2H, 13C) and radiogenic (3H, 14C) isotopes, and resulting data were used in conjunction with hydrogeologic information (e.g. hydraulic head and hydrostratigraphy). Results show that recent recharge (<60 years) has occurred within mountain systems along the basin margins and in shallow floodplain aquifers adjacent to the San Pedro River. Groundwater in the lower basin fill aquifer (semi confined) was recharged at high elevation in the fractured bedrock and has been extensively modified by water-rock reactions (increasing F and Sr, decreasing 14C) over long timescales (up to 35,000 years BP). Distinct solute and isotope geochemistries between the lower and upper basin fill aquifers show the importance of a clay confining unit on groundwater flow in the basin, which minimizes vertical groundwater movement.

  2. Probability distributions of hydraulic conductivity for the hydrogeologic units of the Death Valley regional ground-water flow system, Nevada and California

    SciTech Connect

    Belcher, W.R.; Sweetkind, D.S.; Elliott, P.E.

    2002-11-19

    The use of geologic information such as lithology and rock properties is important to constrain conceptual and numerical hydrogeologic models. This geologic information is difficult to apply explicitly to numerical modeling and analyses because it tends to be qualitative rather than quantitative. This study uses a compilation of hydraulic-conductivity measurements to derive estimates of the probability distributions for several hydrogeologic units within the Death Valley regional ground-water flow system, a geologically and hydrologicaly complex region underlain by basin-fill sediments, volcanic, intrusive, sedimentary, and metamorphic rocks. Probability distributions of hydraulic conductivity for general rock types have been studied previously; however, this study provides more detailed definition of hydrogeologic units based on lithostratigraphy, lithology, alteration, and fracturing and compares the probability distributions to the aquifer test data. Results suggest that these probability distributions can be used for studies involving, for example, numerical flow modeling, recharge, evapotranspiration, and rainfall runoff. These probability distributions can be used for such studies involving the hydrogeologic units in the region, as well as for similar rock types elsewhere. Within the study area, fracturing appears to have the greatest influence on the hydraulic conductivity of carbonate bedrock hydrogeologic units. Similar to earlier studies, we find that alteration and welding in the Tertiary volcanic rocks greatly influence conductivity. As alteration increases, hydraulic conductivity tends to decrease. Increasing degrees of welding appears to increase hydraulic conductivity because welding increases the brittleness of the volcanic rocks, thus increasing the amount of fracturing.

  3. A GIS cost model to assess the availability of freshwater, seawater, and saline groundwater for algal biofuel production in the United States.

    PubMed

    Venteris, Erik R; Skaggs, Richard L; Coleman, Andre M; Wigmosta, Mark S

    2013-05-01

    A key advantage of using microalgae for biofuel production is the ability of some algal strains to thrive in waters unsuitable for conventional crop irrigation such as saline groundwater or seawater. Nonetheless, the availability of sustainable water supplies will provide significant challenges for scale-up and development of algal biofuels. We conduct a partial techno-economic assessment based on the availability of freshwater, saline groundwater, and seawater for use in open pond algae cultivation systems. We explore water issues through GIS-based models of algae biofuel production, freshwater supply (constrained to less than 5% of mean annual flow per watershed) and costs, and cost-distance models for supplying seawater and saline groundwater. We estimate that, combined, these resources can support 9.46 × 10(7) m(3) yr(-1) (25 billion gallons yr(-1)) of renewable biodiesel production in the coterminous United States. Achievement of larger targets requires the utilization of less water efficient sites and relatively expensive saline waters. Despite the addition of freshwater supply constraints and saline water resources, the geographic conclusions are similar to our previous results. Freshwater availability and saline water delivery costs are most favorable for the coast of the Gulf of Mexico and Florida peninsula, where evaporation relative to precipitation is moderate. As a whole, the barren and scrub lands of the southwestern U.S. have limited freshwater supplies, and large net evaporation rates greatly increase the cost of saline alternatives due to the added makeup water required to maintain pond salinity. However, this and similar analyses are particularly sensitive to knowledge gaps in algae growth/lipid production performance and the proportion of freshwater resources available, key topics for future investigation. PMID:23495893

  4. Groundwater Flow Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nevada Test Site, Nye County, Nevada, Revision 0

    SciTech Connect

    Greg Ruskauff

    2006-06-01

    The Pahute Mesa groundwater flow model supports the FFACO UGTA corrective action strategy objective of providing an estimate of the vertical and horizontal extent of contaminant migration for each CAU in order to predict contaminant boundaries. A contaminant boundary is the model-predicted perimeter that defines the extent of radionuclide-contaminated groundwater from underground nuclear testing above background conditions exceeding Safe Drinking Water Act (SDWA) standards. The contaminant boundary will be composed of both a perimeter boundary and a lower hydrostratigraphic unit (HSU) boundary. Additional results showing contaminant concentrations and the location of the contaminant boundary at selected times will also be presented. These times may include the verification period, the end of the five-year proof-of-concept period, as well as other times that are of specific interest. The FFACO (1996) requires that the contaminant transport model predict the contaminant boundary at 1,000 years and “at a 95% level of confidence.” The Pahute Mesa Phase I flow model described in this report provides, through the flow fields derived from alternative hydrostratigraphic framework models (HFMs) and recharge models, one part of the data required to compute the contaminant boundary. Other components include the simplified source term model, which incorporates uncertainty and variability in the factors that control radionuclide release from an underground nuclear test (SNJV, 2004a), and the transport model with the concomitant parameter uncertainty as described in Shaw (2003). The uncertainty in all the above model components will be evaluated to produce the final contaminant boundary. This report documents the development of the groundwater flow model for the Central and Western Pahute Mesa CAUs.

  5. Cocaine dependence treatment on an inpatient detoxification unit.

    PubMed

    Wallace, B C

    1987-01-01

    A psychoanalytic-developmental treatment model includes individual and group psychotherapy which enables compulsive freebase cocaine smokers to articulate explanations for their drug dependence. Relapse prevention education includes recommendations for aftercare treatment. Psychosocial history and DSM-III diagnostic data (N = 31) reveals histories of dysfunctional family dynamics, high rates of depressive disorders, and personality disorders. A case history illustrates application of our treatment model and problems in currently available post-detox treatment. Residential therapeutic communities (TCs) need to offer variable program lengths and specialized crack residences in therapeutic milieus with trained clinical staff. TC programs should offer inpatient psychotherapy, family therapy, and provide direct entrance into program affiliated outpatient services. Recommendations for outpatient services include adjuncts to established anonymous self-help group networks in order to reduce changes of relapse. PMID:3041012

  6. SURFACE-ALTERED ZEOLITES AS PERMEABLE BARRIERS FOR IN SITU TREATMENT OF CONTAMINATED GROUNDWATER

    SciTech Connect

    Robert S. Bowman; Pengfei Zhang; Xian Tao

    2002-03-01

    This report summarizes experiments to develop and test surfactant-modified zeolite/zero-valent iron (SMZ/ZVI) pellets for permeable reactive barriers to treat groundwater contamination. Coating a glass foam core with a mixture of hexadecyltrimethylammonium surfactant, zeolite, and ZVI produced a high hydraulic conductivity, mechanically stable pellet. Laboratory experiments showed that the pellets completely removed soluble chromate from aqueous solution, and reduced perchloroethylene (PCE) concentrations more than pellets that lacked surfactant. Based upon the laboratory results, they predicted a 1-m-wide SMZ/ZVI barrier that would reduce PCE concentrations by four orders of magnitude. Thirteen cubic meters (470 cubic feet) of SMZ/ZVI pellets were manufactured and emplaced in a permeable barrier test facility. A controlled plume of chromate and PCE was allowed to contact the barrier for four weeks. The entire plume was captured by the barrier. No chromate was detected downgradient of the barrier. The PCE broke through the barrier after four weeks, and downgradient concentrations ultimately exceeded 10% of the influent PCE. The less-than-expected PCE reduction was attributed to insufficient surfactant content, the large size, and pH-altering characteristics of the bulk-produced pellets. The pellets developed here can be improved to yield a performance- and cost-competitive permeable barrier material.

  7. TECHNOLOGY EVALUATION REPORT: BIOLOGICAL TREATMENT OF WOOD PRESERVING SITE GROUNDWATER BY BIOTROL, INC.

    EPA Science Inventory

    This report provides the in-depth data analysis from the SITE Program's six-week demonstration of BioTrol's Aqueous Treatment System (BATS) at the MacGillis and Gibbs Company wood treatment facility in New Brighton, Minnesota. he pilot scale (5gpm), fixed-film biological system u...

  8. Baseline groundwater quality in national park units within the Marcellus and Utica Shale gas plays, New York, Pennsylvania, and West Virginia, 2011

    USGS Publications Warehouse

    Eckhardt, David A.V.; Sloto, Ronald A.

    2012-01-01

    Groundwater samples were collected from 15 production wells and 1 spring at 9 national park units in New York, Pennsylvania, and West Virginia in July and August 2011 and analyzed to characterize the quality of these water supplies. The sample sites generally were selected to represent areas of potential effects on water quality by drilling and development of gas wells in Marcellus Shale and Utica Shale areas of the northeastern United States. The groundwater samples were analyzed for 53 constituents, including nutrients, major inorganic constituents, trace elements, chemical oxygen demand, radioactivity, and dissolved gases, including methane and radon-222. Results indicated that the groundwater used for water supply at the selected national park units is generally of acceptable quality, although concentrations of some constituents exceeded at least one drinking-water guideline at several wells. Nine analytes were detected in concentrations that exceeded Federal drinking-water standards, mostly secondary standards that define aesthetic properties of water, such as taste and odor. One sample had an arsenic concentration that exceeded the U.S. Environmental Protection Agency maximum contaminant level (MCL) of 10 micrograms per liter (μg/L). The pH, which is a measure of acidity (hydrogen ion activity), ranged from 4.8 to 8.4, and in 5 of the 16 samples, the pH values were outside the accepted U.S. Environmental Protection Agency secondary maximum contaminant level (SMCL) range of 6.5 to 8.5. The concentration of total dissolved solids exceeded the SMCL of 500 milligrams per liter (mg/L) at four sites. The sulfate concentration exceeded the SMCL of 250 mg/L concentration in one sample, and the fluoride concentration exceeded the SMCL of 2 mg/L in one sample. Sodium concentrations exceeded the U.S. Environmental Protection Agency drinking water health advisory of 60 mg/L at four sites. Iron concentrations exceeded the SMCL of 300 μg/L in two samples, and manganese

  9. Fate of sulfamethoxazole, 4-nonylphenol, and 17β-estradiol in groundwater contaminated by wastewater treatment plant effluent

    USGS Publications Warehouse

    Barber, Larry B.; Keefe, Steffanie H.; LeBlanc, Denis R.; Bradley, Paul M.; Chapelle, Francis H.; Meyer, Michael T.; Loftin, Keith A.; Koplin, Dana W.; Rubio, Fernando

    2009-01-01

    Organic wastewater contaminants (OWCs) were measured in samples collected from monitoring wells located along a 4.5-km transect of a plume of groundwater contaminated by 60 years of continuous rapid infiltration disposal of wastewater treatment plant effluent. Fifteen percent of the 212 OWCs analyzed were detected, including the antibiotic sulfamethoxazole (SX), the nonionic surfactant degradation product 4-nonylphenol (NP), the solvent tetrachloroethene (PCE), and the disinfectant 1,4-dichlorobenzene (DCB). Comparison of the 2005 sampling results to data collected from the same wells in 1985 indicates that PCE and DCB are transported more rapidly in the aquifer than NP, consistent with predictions based on compound hydrophobicity. Natural gradient in situ tracer experiments were conducted to evaluate the subsurface behavior of SX, NP, and the female sex hormone 17β-estradiol (E2) in two oxic zones in the aquifer: (1) a downgradient transition zone at the interface between the contamination plume and the overlying uncontaminated groundwater and (2) a contaminated zone located beneath the infiltration beds, which have not been loaded for 10 years. In both zones, breakthrough curves for the conservative tracer bromide (Br−) and SX were nearly coincident, whereas NP and E2 were retarded relative to Br− and showed mass loss. Retardation was greater in the contaminated zone than in the transition zone. Attenuation of NP and E2 in the aquifer was attributed to biotransformation, and oxic laboratory microcosm experiments using sediments from the transition and contaminated zones show that uniform-ring-labeled 14C 4-normal-NP was biodegraded more rapidly (30−60% recovered as 14CO2 in 13 days) than 4-14C E2 (20−90% recovered as 14CO2in 54 days). There was little difference in mineralization potential between sites.

  10. Spatial Analysis of Contaminants in 200 West Area Groundwater in Support of the 200-ZP-1 Operable Unit Pre-Conceptual Remedy Design

    SciTech Connect

    Murray, Christopher J.; Bott, Yi-Ju

    2008-12-30

    This report documents a preliminary spatial and geostatistical analysis of the distribution of several contaminants of interest (COIs) in groundwater within the unconfined aquifer beneath the 200 West Area of the Hanford Site. The contaminant plumes of interest extend within the 200-ZP-1 and 200-UP-1 groundwater operable units. The COIs included in the PNNL study were carbon tetrachloride (CTET), technetium-99 (Tc-99), iodine-129 (I-129), chloroform, plutonium, uranium, trichloroethylene (TCE), and nitrate. The project included three tasks. Task 1 involved the development of a database that includes all relevant depth-discrete data on the distribution of COIs in the study area. The second task involved a spatial analysis of the three-dimensional (3D) distribution of data for the COIs in the study area. The main focus of the task was to determine if sufficient data are available for geostatistical mapping of the COIs in 3D. Task 3 involved the generation of numerical grids of the concentration of CTET, chloroform, and Tc-99.

  11. Remedial investigation concept plan for the groundwater operable units at the chemical plant area and the ordnance works area, Weldon Spring, Missouri

    SciTech Connect

    1999-07-15

    The U.S. Department of Energy (DOE) and the U.S. Department of the Army (DA) are conducting cleanup activities at two properties--the DOE chemical plant area and the DA ordnance works area (the latter includes the training area)--located in the Weldon Spring area in St. Charles County, Missouri. These areas are on the National Priorities List (NPL), and cleanup activities at both areas are conducted in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as amended. DOE and DA are conducting a joint remedial investigation (RI) and baseline risk assessment (BRA) as part of the remedial investigation/feasibility study (RI/FS) for the groundwater operable units for the two areas. This joint effort will optimize further data collection and interpretation efforts and facilitate overall remedial decision making since the aquifer of concern is common to both areas. A Work Plan issued jointly in 1995 by DOE and the DA discusses the results of investigations completed at the time of preparation of the report. The investigations were necessary to provide an understanding of the groundwater system beneath the chemical plant area and the ordnance works area. The Work Plan also identifies additional data requirements for verification of the evaluation presented.

  12. A Retrospective Analysis on the Occurrence of Arsenic in Ground-Water Resources of the United States and Limitations in Drinking-Water-Supply Characterizations

    USGS Publications Warehouse

    Focazio, Michael J.; Welch, Alan H.; Watkins, Sharon A.; Helsel, Dennis R.; Horn, Marilee A.

    2000-01-01

    The Safe Drinking Water Act, as amended in 1996, requires the U.S. Environmental Protection Agency (USEPA) to review current drinking-water standards for arsenic, propose a maximum contaminant level for arsenic by January 1, 2000, and issue a final regulation by January, 2001. Quantification of the national occurrence of targeted ranges in arsenic concentration in ground water used for public drinking-water supplies is an important component of USEPA's regulatory process. Data from the U.S. Geological Survey (USGS) National Water Information System (NWIS) were used in a retrospective analysis of arsenic in the ground-water resources of the United States. The analysis augments other existing sources of data on the occurrence of arsenic collected in ground water at public water-supply systems.The USGS, through its District offices and national programs, has been compiling data for many years on arsenic concentrations collected from wells used for public water supply, research, agriculture, industry, and domestic water supply throughout the United States. These data have been collected for a variety of purposes ranging from simple descriptions of the occurrence of arsenic in local or regional ground-water resources to detailed studies on arsenic geochemistry associated with contamination sites. A total of 18,864 sample locations were selected from the USGS NWIS data base regardless of well type, of which 2,262 were taken from public water-supply sources. Samples with non-potable water (dissolved-solids concentration greater than 2,000 milligrams per liter and water temperature greater than 50o Celsius) were not selected for the retrospective analysis and other criteria for selection included the amount and type of ancillary data available for each sample. The 1,528 counties with sufficient data included 76 percent of all large public water-supply systems (serving more than 10,000 people) and 61 percent of all small public water-supply systems (serving more than 1

  13. Oxidant Selection for the Treatment of Manganese (II), Iron (II), and Arsenic (III) in Groundwaters

    EPA Science Inventory

    In order to comply with the United States Environmental Protection Agency’s (U.S. EPA’s) arsenic standard and the manganese and iron secondary maximum contaminant levels (MCLs) in water (10µg/L, 50µg/L, and 300µg/L, respectively), many Midwestern water utilities must add a strong...

  14. Technical framework for groundwater restoration

    SciTech Connect

    Not Available

    1991-04-01

    This document provides the technical framework for groundwater restoration under Phase II of the Uranium Mill Tailings Remedial Action (UMTRA) Project. A preliminary management plan for Phase II has been set forth in a companion document titled ``Preplanning Guidance Document for Groundwater Restoration``. General principles of site characterization for groundwater restoration, restoration methods, and treatment are discussed in this document to provide an overview of standard technical approaches to groundwater restoration.

  15. Internal porosity of mineral coating supports microbial activity in rapid sand filters for groundwater treatment.

    PubMed

    Gülay, Arda; Tatari, Karolina; Musovic, Sanin; Mateiu, Ramona V; Albrechtsen, Hans-Jørgen; Smets, Barth F

    2014-11-01

    A mineral coating develops on the filter grain surface when groundwater is treated via rapid sand filtration in drinking water production. The coating changes the physical and chemical properties of the filter material, but little is known about its effect on the activity, colonization, diversity, and abundance of microbiota. This study reveals that a mineral coating can positively affect the colonization and activity of microbial communities in rapid sand filters. To understand this effect, we investigated the abundance, spatial distribution, colonization, and diversity of all and of nitrifying prokaryotes in filter material with various degrees of mineral coating. We also examined the physical and chemical characteristics of the mineral coating. The amount of mineral coating correlated positively with the internal porosity, the packed bulk density, and the biologically available surface area of the filter material. The volumetric NH4 (+) removal rate also increased with the degree of mineral coating. Consistently, bacterial 16S rRNA and amoA abundances positively correlated with increased mineral coating levels. Microbial colonization could be visualized mainly within the outer periphery (60.6 ± 35.6 μm) of the mineral coating, which had a thickness of up to 600 ± 51 μm. Environmental scanning electron microscopic (E-SEM) observations suggested an extracellular polymeric substance-rich matrix and submicron-sized bacterial cells. Nitrifier diversity profiles were similar irrespective of the degree of mineral coating, as indicated by pyrosequencing analysis. Overall, our results demonstrate that mineral coating positively affects microbial colonization and activity in rapid sand filters, most likely due to increased volumetric cell abundances facilitated by the large surface area of internal mineral porosity accessible for microbial colonization. PMID:25192987

  16. Internal Porosity of Mineral Coating Supports Microbial Activity in Rapid Sand Filters for Groundwater Treatment

    PubMed Central

    Gülay, Arda; Tatari, Karolina; Musovic, Sanin; Mateiu, Ramona V.; Albrechtsen, Hans-Jørgen

    2014-01-01

    A mineral coating develops on the filter grain surface when groundwater is treated via rapid sand filtration in drinking water production. The coating changes the physical and chemical properties of the filter material, but little is known about its effect on the activity, colonization, diversity, and abundance of microbiota. This study reveals that a mineral coating can positively affect the colonization and activity of microbial communities in rapid sand filters. To understand this effect, we investigated the abundance, spatial distribution, colonization, and diversity of all and of nitrifying prokaryotes in filter material with various degrees of mineral coating. We also examined the physical and chemical characteristics of the mineral coating. The amount of mineral coating correlated positively with the internal porosity, the packed bulk density, and the biologically available surface area of the filter material. The volumetric NH4+ removal rate also increased with the degree of mineral coating. Consistently, bacterial 16S rRNA and amoA abundances positively correlated with increased mineral coating levels. Microbial colonization could be visualized mainly within the outer periphery (60.6 ± 35.6 μm) of the mineral coating, which had a thickness of up to 600 ± 51 μm. Environmental scanning electron microscopic (E-SEM) observations suggested an extracellular polymeric substance-rich matrix and submicron-sized bacterial cells. Nitrifier diversity profiles were similar irrespective of the degree of mineral coating, as indicated by pyrosequencing analysis. Overall, our results demonstrate that mineral coating positively affects microbial colonization and activity in rapid sand filters, most likely due to increased volumetric cell abundances facilitated by the large surface area of internal mineral porosity accessible for microbial colonization. PMID:25192987

  17. Geodetic evidence for subsidence due to groundwater withdrawal in many parts of the United States of America

    NASA Astrophysics Data System (ADS)

    Chi, S. C.; Reilinger, R. E.

    1984-01-01

    Analysis of repeated levelings conducted by the National Geodetic Survey indicates many locations of relative subsidence in the U.S.A. Specific criteria are used to identify those subsidence features which most likely result from sediment compaction due to lowering of water levels in underground aquifer systems. Previously reported areas of such subsidence that seem to be confirmed by this study include: south-central Arizona; Savannah, Georgia; Pecos and Houston-Galveston, Texas; Denver, Colorado; San Joaquin Valley, Santa Clara Valley, Saugus Basin, Los Angeles Basin and Bunker Hill-San Timoteo, California; Milford, Utah; Raft River Valley, Idaho; Baton Rouge and New Orleans, Louisiana; and Las Vegas, Nevada. In addition, our analysis indicates that such subsidence is more widespread than previously reported occurring in a number of locations within the Atlantic and Gulf of Mexico coastal plains and along the Mississippi Valley as well as in many other unconsolidated sedimentary basins from which groundwater has been extracted and for which repeated leveling measurements are available. More than 30 new locations of subsidence possibly due to water withdrawal have been identified. The best documented of these include: Ventura, Ontario and San Pedro-Santa Monica, California; Monroe and Alexandria, Louisiana, and Jackson, Mississippi. Subsidence in newly identified locations ranges from several tens of millimeters to a few hundred millimeters over distances of ˜ 10-60 km and times of 2-48 yr. Subsidence may also have occurred in other groundwater basins where water levels have been drawn down, and remained undetected because of a lack of repeated levelings. It is important to be aware of and to continue to monitor such effects because of increasing rates of utilization of groundwater resources and the potential for significant engineering problems due to surface movements. In addition, identifying cases of subsidence due to water withdrawal is essential in order to

  18. Development and Operation of a Passive-Flow Treatment System for (Sup 90)Sr-Contaminated Groundwater

    SciTech Connect

    Kirkham, P.S.; Taylor, P.A.

    1999-02-28

    Seep C was a free-flowing stream of groundwater that emerged in a narrow valley below the old low-level waste (LLW) disposal trenches in Solid Waste Storage Area 5 (SWSA 5) at Oak Ridge National Laboratory (ORNL). The flow rate of the seep water was strongly influenced by rainfall, and typically ranged from 0.5 to 8 L/min. The seep water entered Melton Branch, a small stream that joins White Oak Creek before exiting the ORNL boundary. The seep water contained high concentrations of {sup 90}Sr (10,000 to 20,000 Bq/L) and, before the full-scale treatment system was installed, contributed about 25% of all the {sup 90}Sr leaving ORNL. Seep C was identified as a primary source of off-site contaminant transport and was designated for an early removal action under the Comprehensive Environmental Response and Liability Act (CERCLA). A passive flow treatment system was chosen as the most cost-effective method for treating the water.

  19. Aquifer Testing Recommendations for Well 299-W15-225: Supporting Phase I of the 200-ZP-1 Groundwater Operable Unit Remedial Design

    SciTech Connect

    Spane, Frank A.; Newcomer, Darrell R.

    2009-03-10

    Aquifer characterization needs are currently being assessed to optimize pump-and-treat remedial strategies within the 200-ZP-1 Operable Unit (OU), specifically for the immediate area of the 241-TX-TY Tank Farm. Currently, 14 extraction wells are actively used in the Interim Record of Decision ZP-1 pump-and-treat system to remediate the existing groundwater contamination within this general area. Four of these wells (299-W15-40, 299-W15-43, 299-W15-44, and 299-W15-765) are targeted to remediate contamination within the immediate 241-TX-TY Tank Farm area. The major contaminant of concern (COC) for the 200-ZP-1 OU is carbon tetrachloride. Other COC’s include total chromium (trivalent [III] and hexavalent [VI], nitrate, trichloroethlyene, iodine-129, technetium-99, and tritium.

  20. Performance of a Zerovalent Iron Reactive Barrier for the Treatment of Arsenic in Groundwater: Part 1. Hydrogeochemical Studies

    EPA Science Inventory

    Developments and improvements of remedial technologies are needed to effectively manage arsenic contamination in groundwater at hazardous waste sites. In June 2005, a 9.1 m long, 14 m deep, and 1.8 to 2.4 m wide (in the direction of groundwater flow) pilot-scale permeable reacti...

  1. Pilot Study of Behavioral Treatment in Dementia Care Units.(practice Concepts)(author Abstract)

    ERIC Educational Resources Information Center

    Lichtenberg, Peter A.; Kemp-Havican, Julie; MacNeill, Susan E.; Johnson, Amanda Schafer

    2005-01-01

    Purpose: This article reports on the development and use of behavioral treatment as a well-being intervention for individuals with dementia residing at special care units in a nursing home. Design and Methods: The project took place upon the construction and opening of two new homelike units for dementia care in a rural community-care center.…

  2. Assessing quality and quantity of groundwater DOC in relation to plant export from different over-winter green-cover treatments in tillage farming systems

    NASA Astrophysics Data System (ADS)

    Premrov, Alina; Coxon, Catherine; Hackett, Richard; Richards, Karl

    2010-05-01

    The biogeochemistry of nitrogen is often connected to carbon and C/N dynamics. The dissolved organic carbon (DOC) electron donor availability can be related to groundwater denitrification (Buss, et al. 2005). Therefore groundwater nitrate attenuation processes are also frequently linked to carbon availability. In recent years the role of over-winter green cover in tillage farming has been studied extensively. Nevertheless further research on the biogeochemical effect of green cover on soil/sediment and groundwater quality is still needed. In particular plant roots are known to exude different types of organic compounds, but their role in groundwater quality has not been investigated in depth. According to Cannavo et al. (2004a,b), in addition to quantity, the quality of water-extractable soil organic matter (e.g. molecular size/weight) has also an important role for microbial activity. In this study we investigate the effect of over-winter green-cover on potential DOC export to shallow groundwater (2 - 5 m below ground level), located on tillage land in Oak Park, Carlow, Ireland. The experiment includes three over-winter green-cover treatments: natural green-cover, mustard and no-cover (sprayed with herbicide following harvest); and is underlain by a sand and gravel aquifer. The site is equipped with 4 shallow piezometers per treatment (total no. of piezometers is 20, including treatments and surrounding piezometers). In addition to monitoring the quantity of DOC concentrations in shallow groundwater under different green cover treatments over time, an attempt was made to evaluate the quality of dissolved organic matter in shallow groundwater using Excitation Emission Fluorescence Matrix (EEFM) profiles obtained from analyses performed on a Varian Fluorescence Spectrophotometer of a single batch of samples (from all 20 installed piezometers in September 2009). To evaluate the quality of dissolved organic matter in shallow groundwater, computation of the

  3. Phase I Hydrologic Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 99: Rainier Mesa/Shoshone Mountain, Nevada Test Site, Nye County, Nevada, Revision 1

    SciTech Connect

    Nathan Bryant

    2008-05-01

    This document presents a summary and framework of the available hydrologic data and other information directly relevant to the development of the Rainier Mesa/Shoshone Mountain (RMSM) Corrective Action Unit (CAU) 99 groundwater flow models. Where appropriate, data and information documented elsewhere are briefly summarized with reference to the complete documentation.

  4. Phase I Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 99: Rainier Mesa/Shoshone Mountain, Nevada Test Site, Nye County, Nevada, Revision 1

    SciTech Connect

    Nathan Bryant

    2008-05-01

    This document presents a summary and framework of available transport data and other information directly relevant to the development of the Rainier Mesa/Shoshone Mountain (RMSM) Corrective Action Unit (CAU) 99 groundwater transport model. Where appropriate, data and information documented elsewhere are briefly summarized with reference to the complete documentation.

  5. Bioremediation of contaminated groundwater

    SciTech Connect

    Hazen, T.C.; Fliermans, C.B.

    1992-12-31

    The present invention relates to a method for in situ bioremediation of contaminated soil and groundwater. In particular, the invention relates to remediation of contaminated soil and groundwater by the injection of nutrients to stimulate growth of pollutant-degrading microorganisms. The United States Government has rights in this invention pursuant to Contract No. DE-AC09-89SR18035 between the US Department of Energy and Westinghouse Savannah River Company.

  6. Geophysical and hydrogeological characterisation of the impacts of on-site wastewater treatment discharge to groundwater in a poorly productive bedrock aquifer.

    PubMed

    Donohue, Shane; McCarthy, Valerie; Rafferty, Patrick; Orr, Alison; Flynn, Raymond

    2015-08-01

    Contaminants discharging from on-site wastewater treatment systems (OSWTSs) can impact groundwater quality, threatening human health and surface water ecosystems. Risk of negative impacts becomes elevated in areas of extreme vulnerability with high water tables, where thin unsaturated intervals limit vadose zone attenuation. A combined geophysical/hydrogeological investigation into the effects of an OSWTS, located over a poorly productive aquifer (PPA) with thin subsoil cover, aimed to characterise effluent impacts on groundwater. Groundwater, sampled from piezometers down-gradient of the OSWTS percolation area displayed spatially erratic, yet temporally consistent, contaminant distributions. Electrical resistivity tomography identified an area of gross groundwater contamination close to the percolation area and, when combined with seismic refraction and water quality data, indicated that infiltrating effluent reaching the water table discharged to a deeper more permeable zone of weathered shale resting on more competent bedrock. Subsurface structure, defined by geophysics, indicated that elevated chemical and microbiological contaminant levels encountered in groundwater samples collected from piezometers, down-gradient of sampling points with lower contaminant levels, corresponded to those locations where piezometers were screened close to the weathered shale/competent rock interface; those immediately up-gradient were too shallow to intercept this interval, and thus the more impacted zone of the contaminant plume. Intermittent occurrence of faecal indicator bacteria more than 100m down gradient of the percolation area suggested relatively short travel times. Study findings highlight the utility of geophysics as part of multidisciplinary investigations for OSWTS contaminant plume characterisation, while also demonstrating the capacity of effluent discharging to PPAs to impact groundwater quality at distance. Comparable geophysical responses observed in similar

  7. Field evaluation of a horizontal well recirculation system for groundwater treatment: Field demonstration at X-701B Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    SciTech Connect

    Korte, N.; Muck, M.; Kearl, P.; Siegrist, R.; Schlosser, R.; Zutman, J.; Houk, T.

    1998-08-01

    This report describes the field-scale demonstration performed as part of the project, In Situ Treatment of Mixed Contaminants in Groundwater. This project was a 3{1/2} year effort comprised of laboratory work performed at Oak Ridge National Laboratory and fieldwork performed at the US Department of Energy (DOE) Portsmouth Gaseous Diffusion Plant (PORTS). The overall goal of the project was to evaluate in situ treatment of groundwater using horizontal recirculation coupled with treatment modules. Specifically, horizontal recirculation was tested because of its application to thin, interbedded aquifer zones. Mixed contaminants were targeted because of their prominence at DOE sites and because they cannot be treated with conventional methods. The project involved several research elements, including treatment process evaluation, hydrodynamic flow and transport modeling, pilot testing at an uncontaminated site, and full-scale testing at a contaminated site. This report presents the results of the work at the contaminated site, X-701B at PORTS. Groundwater contamination at X-701B consists of trichloroethene (TCE) (concentrations up to 1800 mg/L) and technetium-998 (Tc{sup 99}) (activities up to 926 pCi/L).

  8. Annual report for RCRA groundwater monitoring projects at Hanford Site facilities for 1993

    SciTech Connect

    Not Available

    1994-02-01

    This report presents the annual hydrogeologic evaluation of 20 Resource Conservation and Recovery Act of 1976 groundwater monitoring projects and 1 nonhazardous waste facility at the US Department of Energy`s Hanford Site. Most of the projects no longer receive dangerous waste; a few projects continue to receive dangerous waste constituents for treatment, storage, or disposal. The 20 RCRA projects comprise 30 waste management units. Ten of the units are monitored under groundwater quality assessment status because of elevated levels of indicator parameters. The impact of those units on groundwater quality, if any, is being investigated. If dangerous waste or waste constituents have entered groundwater, their concentration, distribution, and rate of migration are evaluated. Groundwater is monitored at the other 20 units to detect contamination, should it occur. This report provides an interpretation of groundwater data collected at the waste management units between October 1992 and September 1993. Recent groundwater quality is also described for the 100, 200, 300, and 600 Areas and for the entire Hanford Site. Widespread contaminants include nitrate, chromium, carbon tetrachloride, tritium, and other radionuclides.

  9. Comparison of biotic and abiotic treatment approaches for co-mingled perchlorate, nitrate, and nitramine explosives in groundwater

    NASA Astrophysics Data System (ADS)

    Schaefer, C. E.; Fuller, M. E.; Condee, C. W.; Lowey, J. M.; Hatzinger, P. B.

    2007-01-01

    Biological and abiotic approaches for treating co-mingled perchlorate, nitrate, and nitramine explosives in groundwater were compared in microcosm and column studies. In microcosms, microscale zero-valent iron (mZVI), nanoscale zero-valent iron (nZVI), and nickel catalyzed the reduction of RDX and HMX from initial concentrations of 9 and 1 mg/L, respectively, to below detection (0.02 mg/L), within 2 h. The mZVI and nZVI also degraded nitrate (3 mg/L) to below 0.4 mg/L, but none of the metal catalysts were observed to appreciably reduce perchlorate (˜ 5 mg/L) in microcosms. Perchlorate losses were observed after approximately 2 months in columns of aquifer solids treated with mZVI, but this decline appears to be the result of biodegradation rather than abiotic reduction. An emulsified vegetable oil substrate was observed to effectively promote the biological reduction of nitrate, RDX and perchlorate in microcosms, and all four target contaminants in the flow-through columns. Nitrate and perchlorate were biodegraded most rapidly, followed by RDX and then HMX, although the rates of biological reduction for the nitramine explosives were appreciably slower than observed for mZVI or nickel. A model was developed to compare contaminant degradation mechanisms and rates between the biotic and abiotic treatments.

  10. The role of interbasin groundwater transfers in geologically complex terranes, demonstrated by the Great Basin in the western United States

    NASA Astrophysics Data System (ADS)

    Nelson, Stephen T.; Mayo, Alan L.

    2014-06-01

    In the Great Basin, USA, bedrock interbasin flow is conceptualized as the mechanism by which large groundwater fluxes flow through multiple basins and intervening mountains. Interbasin flow is propounded based on: (1) water budget imbalances, (2) potential differences between basins, (3) stable isotope evidence, and (4) modeling studies. However, water budgets are too imprecise to discern interbasin transfers and potential differences may exist with or without interbasin fluxes. Potentiometric maps are dependent on conceptual underpinnings, leading to possible false inferences regarding interbasin transfers. Isotopic evidence is prone to non-unique interpretation and may be confounded by the effects of climate change. Structural and stratigraphic considerations in a geologically complex region like the Great Basin should produce compartmentalization, where increasing aquifer size increases the odds of segmentation along a given flow path. Initial conceptual hypotheses should explain flow with local recharge and short flow paths. Where bedrock interbasin flow is suspected, it is most likely controlled by diversion of water into the damage zones of normal faults, where fault cores act as barriers. Large-scale bedrock interbasin flow where fluxes must transect multiple basins, ranges, and faults at high angles should be the conceptual model of last resort.

  11. Ground-water recharge and flowpaths near the edge of the Decorah-Platteville-Glenwood confining unit, Rochester, Minnesota

    USGS Publications Warehouse

    Lindgren, Richard J.

    2001-01-01

    The water withdrawn by pumped wells or discharged to Bear Creek is derived predominantly from areal recharge near the edge of the Decorah-Platteville-Glenwood confining unit (0.47 ft3/s), rather than from water that has leaked downward through the Decorah unit (0.03 ft3/s). Model simulated discharge through springs and seeps in the lower part of the upper carbonate aquifer (0.21 ft3/s) represents a potential source of water to the St. Peter-Prairie du Chien-Jordan aquifer.

  12. Removal of As, Mn, Mo, Se, U, V and Zn from groundwater by zero-valent iron in a passive treatment cell: reaction progress modeling

    NASA Astrophysics Data System (ADS)

    Morrison, Stan J.; Metzler, Donald R.; Dwyer, Brian P.

    2002-05-01

    Three treatment cells were operated at a site near Durango, CO. One treatment cell operated for more than 3 years. The treatment cells were used for passive removal of contamination from groundwater at a uranium mill tailings repository site. Zero-valent iron [Fe(0)] that had been powdered, bound with aluminosilicate and molded into plates was used as a reactive material in one treatment cell. The others used granular Fe(0) and steel wool. The treatment cells significantly reduced concentrations of As, Mn, Mo, Se, U, V and Zn in groundwater that flowed through it. Zero-valent iron [Fe(0)], magnetite (Fe 3O 4), calcite (CaCO 3), goethite (FeOOH) and mixtures of contaminant-bearing phases were identified in the solid fraction of one treatment cell. A reaction progress approach was used to model chemical evolution of water chemistry as it reacted with the Fe(0). Precipitation of calcite, ferrous hydroxide [Fe(OH) 2] and ferrous sulfide (FeS) were used to simulate observed changes in major-ion aqueous chemistry. The amount of reaction progress differed for each treatment cell. Changes in contaminant concentrations were consistent with precipitation of reduced oxides (UO 2, V 2O 3), sulfides (As 2S 3, ZnS), iron minerals (FeSe 2, FeMoO 4) and carbonate (MnCO 3). Formation of a free gas phase and precipitation of minerals contributed to loss of hydraulic conductivity in one treatment cell.

  13. Assessing quality and quantity of groundwater DOC in relation to plant export from different over-winter green-cover treatments in tillage farming systems

    NASA Astrophysics Data System (ADS)

    Premrov, Alina; Coxon, Catherine; Hackett, Richard; Richards, Karl

    2010-05-01

    The biogeochemistry of nitrogen is often connected to carbon and C/N dynamics. The dissolved organic carbon (DOC) electron donor availability can be related to groundwater denitrification (Buss, et al. 2005). Therefore groundwater nitrate attenuation processes are also frequently linked to carbon availability. In recent years the role of over-winter green cover in tillage farming has been studied extensively. Nevertheless further research on the biogeochemical effect of green cover on soil/sediment and groundwater quality is still needed. In particular plant roots are known to exude different types of organic compounds, but their role in groundwater quality has not been investigated in depth. According to Cannavo et al. (2004a,b), in addition to quantity, the quality of water-extractable soil organic matter (e.g. molecular size/weight) has also an important role for microbial activity. In this study we investigate the effect of over-winter green-cover on potential DOC export to shallow groundwater (2 - 5 m below ground level), located on tillage land in Oak Park, Carlow, Ireland. The experiment includes three over-winter green-cover treatments: natural green-cover, mustard and no-cover (sprayed with herbicide following harvest); and is underlain by a sand and gravel aquifer. The site is equipped with 4 shallow piezometers per treatment (total no. of piezometers is 20, including treatments and surrounding piezometers). In addition to monitoring the quantity of DOC concentrations in shallow groundwater under different green cover treatments over time, an attempt was made to evaluate the quality of dissolved organic matter in shallow groundwater using Excitation Emission Fluorescence Matrix (EEFM) profiles obtained from analyses performed on a Varian Fluorescence Spectrophotometer of a single batch of samples (from all 20 installed piezometers in September 2009). To evaluate the quality of dissolved organic matter in shallow groundwater, computation of the

  14. Groundwater Hydrology and Chemistry in and near an Emulsified Vegetable-Oil Injection Zone, Solid Waste Management Unit 17, Naval Weapons Station Charleston, North Charleston, South Carolina, 2004-2009

    USGS Publications Warehouse

    Vroblesky, Don A.; Petkewich, Matthew D.; Lowery, Mark A.; Conlon, Kevin J.; Casey, Clifton C.

    2010-01-01

    The U.S. Geological Survey and the Naval Facilities Engineering Command Southeast investigated the hydrology and groundwater chemistry in the vicinity of an emulsified vegetable-oil injection zone at Solid Waste Management Unit (SWMU) 17, Naval Weapons Station Charleston, North Charleston, South Carolina. In May 2004, Solutions-IES initiated a Phase-I pilot-scale treatability study at SWMU17 involving the injection of an edible oil emulsion into the aquifer near wells 17PS-01, 17PS-02, and 17PS-03 to treat chlorinated solvents. The Phase-I injection of emulsified vegetable oil resulted in dechlorination of trichloroethene (TCE) to cis-1,2-dichloroethene (cDCE), but the dechlorination activity appeared to stall at cDCE, with little further dechlorination of cDCE to vinyl chloride (VC) or to ethene. The purpose of the present investigation was to examine the groundwater hydrology and chemistry in and near the injection zone to gain a better understanding of the apparent remediation stall. It is unlikely that the remediation stall was due to the lack of an appropriate microbial community because groundwater samples showed the presence of Dehalococcoides species (sp.) and suitable enyzmes. The probable causes of the stall were heterogeneous distribution of the injectate and development of low-pH conditions in the injection area. Because groundwater pH values in the injection area were below the range considered optimum for dechlorination activity, a series of tests was done to examine the effect on dechlorination of increasing the pH within well 17PS-02. During and following the in-well pH-adjustment tests, VC concentrations gradually increased in some wells in the injection zone that were not part of the in-well pH-adjustment tests. These data possibly reflect a gradual microbial acclimation to the low-pH conditions produced by the injection. In contrast, a distinct increase in VC concentration was observed in well 17PS-02 following the in-well pH increase. Adjustment

  15. Plutonium Finishing Plan (PFP) Treatment and Storage Unit Waste Analysis Plan

    SciTech Connect

    PRIGNANO, A.L.

    2000-07-01

    The purpose of this waste analysis plan (WAP) is to document waste analysis activities associated with the Plutonium Finishing Plant Treatment and Storage Unit (PFP Treatment and Storage Unit) to comply with Washington Administrative Code (WAC) 173-303-300(1), (2), (4)(a) and (5). The PFP Treatment and Storage Unit is an interim status container management unit for plutonium bearing mixed waste radiologically managed as transuranic (TRU) waste. TRU mixed (TRUM) waste managed at the PFP Treatment and Storage Unit is destined for the Waste Isolation Pilot Plant (WIPP) and therefore is not subject to land disposal restrictions [WAC 173-303-140 and 40 CFR 268]. The PFP Treatment and Storage Unit is located in the 200 West Area of the Hanford Facility, Richland Washington (Figure 1). Because dangerous waste does not include source, special nuclear, and by-product material components of mixed waste, radionuclides are not within the scope of this documentation. The information on radionuclides is provided only for general knowledge.

  16. Meta analysis: underutilization and disparities of treatment among patients with hepatocellular carcinoma in the united states

    PubMed Central

    Tan, Debra; Yopp, Adam; Beg, Muhammad S; Gopal, Purva; Singal, Amit G.

    2013-01-01

    Background Despite wide availability of treatment options for hepatocellular carcinoma (HCC), several studies have suggested underutilization in clinical practice. Aims To quantify utilization rates for HCC treatment among patients with HCC in the United States and summarize patterns of association between utilization rates and patient socio-demographic characteristics. Methods We performed a systematic literature review using the Medline database from January 1989 through March 2013. Two investigators independently extracted data on patient populations, study methods, and results using standardized forms. Pooled treatment rates for any treatment and curative treatment, with 95% confidence intervals, were calculated. Pre-specified subgroup analysis was performed to identify patient-level correlates of treatment utilization. Results We identified 24 studies that met inclusion criteria. The pooled rates of any treatment and curative treatment were 52.8% (95%CI 52.2-53.4%) and 21.8% (95%CI 21.4-22.1%) respectively. Among patients diagnosed at an early stage, the pooled curative treatment rate was 59.0% (95%CI 58.1-59.9%). Elderly, non-Caucasians and patients of low socioeconomic status had lower treatment rates than their counterparts. Conclusions Rates of HCC treatment in the United States, including curative treatment rates among patients detected at an early stage, are disappointingly low. Future efforts should focus on identifying appropriate intervention targets to increase treatment rates and reduce socio-demographic disparities. PMID:23957569

  17. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear, nose, and throat examination and treatment... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300 Ear, nose, and throat examination and treatment unit. (a) Identification. An ear, nose, and...

  18. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat examination and treatment... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300 Ear, nose, and throat examination and treatment unit. (a) Identification. An ear, nose, and...

  19. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear, nose, and throat examination and treatment... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300 Ear, nose, and throat examination and treatment unit. (a) Identification. An ear, nose, and...

  20. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat examination and treatment... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300 Ear, nose, and throat examination and treatment unit. (a) Identification. An ear, nose, and...

  1. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear, nose, and throat examination and treatment... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300 Ear, nose, and throat examination and treatment unit. (a) Identification. An ear, nose, and...

  2. Evaluation of the effectiveness of an urban stormwater treatment unit in Madison, Wisconsin, 1996-97

    USGS Publications Warehouse

    Waschbusch, Robert J.

    1999-01-01

    The material retained in the treatment chamber had high concentrations of lead and PAH and may be subject to special disposal restrictions based on those concentrations and the presence of benzo(a)anthracene. The chemical makeup of the retained material in other similar stormwater treatment units will probably vary depending on the land use and activities in the drainage basin.

  3. Interim Status Closure Plan Open Burning Treatment Unit Technical Area 16-399 Burn Tray

    SciTech Connect

    Vigil-Holterman, Luciana R.

    2012-05-07

    This closure plan describes the activities necessary to close one of the interim status hazardous waste open burning treatment units at Technical Area (TA) 16 at the Los Alamos National Laboratory (LANL or the Facility), hereinafter referred to as the 'TA-16-399 Burn Tray' or 'the unit'. The information provided in this closure plan addresses the closure requirements specified in the Code of Federal Regulations (CFR), Title 40, Part 265, Subparts G and P for the thermal treatment units operated at the Facility under the Resource Conservation and Recovery Act (RCRA) and the New Mexico Hazardous Waste Act. Closure of the open burning treatment unit will be completed in accordance with Section 4.1 of this closure plan.

  4. [Septic shock in intensive care units. Current focus on treatment].

    PubMed

    Arriagada S, Daniela; Donoso F, Alejandro; Cruces R, Pablo; Díaz R, Franco

    2015-01-01

    Essential therapeutic principles in children with septic shock persist over time, although some new concepts have been recently incorporated, and fully awareness of pediatricians and intensivists is essential. Fluid resuscitation is a fundamental intervention, but the kind of ideal fluid has not been established yet, as each of these interventions has specific limitations and there is no evidence supportive of the superiority of one type of fluid. Should septic shock persists despite adequate fluid resuscitation, the use of inotropic medication and/or vasopressors is indicated. New vasoactive drugs can be used in refractory septic shock caused by vasopressors, and the use of hydrocortisone should be considered in children with suspected adrenal insufficiency, as it reduces the need for vasopressors. The indications for red blood cells transfusion or the optimal level of glycemia are still controversial, with no consensus on the threshold value for the use of these blood products or the initiation of insulin administration, respectively. Likewise, the use of high-volume hemofiltration is a controversial issue and further study is needed on the routine recommendation in the course of septic shock. Nutritional support is crucial, as malnutrition is a serious complication that should be properly prevented and treated. The aim of this paper is to provide update on the most recent advances as concerns the treatment of septic shock in the pediatric population. PMID:26323988

  5. Hydrocarbon degrading microbial communities in bench scale aerobic biobarriers for gasoline contaminated groundwater treatment.

    PubMed

    Daghio, Matteo; Tatangelo, Valeria; Franzetti, Andrea; Gandolfi, Isabella; Papacchini, Maddalena; Careghini, Alessandro; Sezenna, Elena; Saponaro, Sabrina; Bestetti, Giuseppina

    2015-07-01

    BTEX compounds (benzene, toluene, ethylbenzene and xylenes) and methyl tert-butyl ether (MTBE) are some of the main constituents of gasoline and can be accidentally released in the environment. In this work the effect of bioaugmentation on the microbial communities in a bench scale aerobic biobarrier for gasoline contaminated water treatment was studied by 16S rRNA gene sequencing. Catabolic genes (tmoA and xylM) were quantified by qPCR, in order to estimate the biodegradation potential, and the abundance of total bacteria was estimated by the quantification of the number of copies of the 16S rRNA gene. Hydrocarbon concentration was monitored over time and no difference in the removal efficiency for the tested conditions was observed, either with or without the microbial inoculum. In the column without the inoculum the most abundant genera were Acidovorax, Bdellovibrio, Hydrogenophaga, Pseudoxanthomonas and Serpens at the beginning of the column, while at the end of the column Thauera became dominant. In the inoculated test the microbial inoculum, composed by Rhodococcus sp. CE461, Rhodococcus sp. CT451 and Methylibium petroleiphilum LMG 22953, was outcompeted. Quantitative PCR results showed an increasing in xylM copy number, indicating that hydrocarbon degrading bacteria were selected during the treatment, although only a low increase of the total biomass was observed. However, the bioaugmentation did not lead to an increase in the degradative potential of the microbial communities. PMID:25747304

  6. Physico-chemical treatment of wastewater from clusters of small scale cotton textile units.

    PubMed

    Pathe, P P; Biswas, A K; Rao, N N; Kaul, S N

    2005-03-01

    Small scale industries can not own individual wastewater treatment facility due to non-availability of land and skilled manpower for operation and maintenance of wastewater treatment plants. A centralized wastewater treatment facility for clusters of small scale industries is appropriate. This concept is gaining popularity in recent years. In India, various textile process operations are undertaken by individual small scale units. The wastewater generated at these units is conveyed to a common effluent treatment facility comprising of equalization, flocculation-clarification, activated sludge process, secondary clarification and finally discharge into inland surface water bodies. The wastewater from small scale cotton textile processing units was highly coloured and alkaline with average BOD and COD concentration of 205 and 790 mg l(-1), respectively. Due to the presence of several dyes, particularly reactive dyes, the biological treatment is often found less effective. Therefore, applicability of various physico-chemical treatment methods needs to be investigated in pursuit of an alternative to biological treatment of textile wastewater. A physico-chemical treatment scheme, involving chemical coagulation-sedimentation, dual media filtration, activated carbon adsorption followed by chemical oxidation was investigated in this paper. The quality of final treated wastewater in terms of BOD and COD was 18-24 and 230-240 mg l(-1), respectively through this scheme. A scheme of treatment comprising coagulation-sedimentation, dual media filtration, activated carbon, chemical oxidation may be considered as an alternative to biological treatment of textile wastewater. PMID:15881028

  7. Addendum for the Groundwater Flow Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nevada Test Site, Nye County, Nevada, Revision 0 (page changes)

    SciTech Connect

    John McCord

    2007-05-01

    This document, which makes changes to Groundwater Flow Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nevada Test Site, Nye County, Nevada, S-N/99205--076, Revision 0 (June 2006) was prepared to address review comments of this final document by the Nevada Division of Environmental Protection (NDEP) in a letter dated July 19, 2006. The document includes revised pages that address NDEP review comments and comments from other document users. Change bars are included on these pages to identify where the text was revised. In addition to the revised pages, the following clarifications are made: • On Plate 1 (inserted in the back of the document), the ET Unit legend has been revised. The revised Plate 1 is included and replaces the original Plate 1. • Some of the Appendix D perturbation sensitivity analysis plots included on the CD for Sections D.3.1 and D.3.2 were not properly aligned. A revised CD is provided with all plots properly aligned.

  8. New Pump and Treat Facility Remedial Action Work Plan for Test Area North (TAN) Final Groundwater Remediation, Operable Unit 1-07B

    SciTech Connect

    D. Vandel

    2003-09-01

    This remedial action work plan identifies the approach and requirements for implementing the medical zone remedial action for Test Area North, Operable Unit 1-07B, at the Idaho National Engineering and Environmental Laboratory (INEEL). This plan details management approach for the construction and operation of the New Pump and Treat Facility. As identified in the remedial design/remedial action scope of work, a separate remedial design/remedial action work plan will be prepared for each remedial component of the Operable Unit 1-07B remedial action. This work plan was originally prepared as an early implementation of the final Phase C remediation. At that time, The Phase C implementation strategy was to use this document as the overall Phase C Work Plan and was to be revised to include the remedial actions for the other remedial zones (hotspot and distal zones). After the completion of Record of Decision Amendment: Technical Support Facility Injection Well (TSF-05) and Surrounding Groundwater Contamination (TSF-23) and Miscellaneous No Action Sites, Final Remedial Action, it was determined that each remedial zone would have it own stand-alone remedial action work plan. Revision 1 of this document converts this document to a stand-alone remedial action plan specific to the implementation of the New Pump and Treat Facility used for plume remediation within the medical zone of the OU 1-07B contaminated plume.

  9. Ground-Water Quality Data in the San Fernando-San Gabriel Study Unit, 2005 - Results from the California GAMA Program

    USGS Publications Warehouse

    Land, Michael; Belitz, Kenneth

    2008-01-01

    Ground-water quality in the approximately 460 square mile San Fernando-San Gabriel study unit (SFSG) was investigated between May and July 2005 as part of the Priority Basin Assessment Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Assessment Project was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The San Fernando-San Gabriel study was designed to provide a spatially unbiased assessment of raw ground-water quality within SFSG, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 52 wells in Los Angeles County. Thirty-five of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study area (grid wells), and seventeen wells were selected to aid in the evaluation of specific water-quality issues or changes in water chemistry along a historic ground-water flow path (understanding wells). The ground-water samples were analyzed for a large number of synthetic organic constituents [volatile organic compounds (VOCs), pesticides and pesticide degradates], constituents of special interest [perchlorate, N-nitrosodimethylamine (NDMA), 1,2,3-trichloropropane (1,2,3-TCP), and 1,4-dioxane], naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial indicators. Naturally occurring isotopes (tritium, and carbon-14, and stable isotopes of hydrogen, oxygen, and carbon), and dissolved noble gases also were measured to help identify the source and age of the sampled ground water. Quality-control samples (blanks, replicates, samples for matrix spikes) were collected at approximately one-fifth (11 of 52) of the wells, and the results for these

  10. Groundwater monitoring plan for the 300 Area process trenches

    SciTech Connect

    Lindberg, J.W.; Chou, C.J.; Johnson, V.G.

    1995-05-23

    This document describes the groundwater monitoring program for the Hanford Site 300 Area Process Trenches (300 APT). The 300 APT are a Resource Conservation and Recovery Act of 1976 (RCRA) regulated unit. The 300 APT are included in the Dangerous Waste Portion of the Resource Conservation and Recovery Act Permit for the Treatment, Storage, and Disposal of Dangerous Waste, Permit No. WA890008967, and are subject to final-status requirements for groundwater monitoring. This document describes a compliance monitoring program for groundwater in the uppermost aquifer system at the 300 APT. This plan describes the 300 APT monitoring network, constituent list, sampling schedule, statistical methods, and sampling and analysis protocols that will be employed for the 300 APT. This plan will be used to meet groundwater monitoring requirements from the time the 300 APT becomes part of the Permit and through the postclosure care period until certification of final closure.

  11. TREATMENT TESTS FOR EX SITU REMOVAL OF CHROMATE & NITRATE & URANIUM (VI) FROM HANFORD (100-HR-3) GROUNDWATER FINAL REPORT

    SciTech Connect

    BECK MA; DUNCAN JB

    1994-01-03

    This report describes batch and ion exchange column laboratory scale studies investigating ex situ methods to remove chromate (chromium [VI]), nitrate (NO{sub 3}{sup -}) and uranium (present as uranium [VI]) from contaminated Hanford site groundwaters. The technologies investigated include: chemical precipitation or coprecipitation to remove chromate and uranium; and anion exchange to remove chromate, uranium and nitrate. The technologies investigated were specified in the 100-HR-3 Groundwater Treatability Test Plan. The method suggested for future study is anion exchange.

  12. Plutonium Finishing Plant Treatment and Storage Unit Dangerous Waste Training Plan

    SciTech Connect

    ENTROP, G.E.

    2000-06-27

    The training program for personnel performing waste management duties pertaining to the Plutonium Finishing Plant (PFP) Treatment and Storage Unit is governed by the general requirements established in the Plutonium Finishing Plant Dangerous Waste Training Plan (PFP DWTP). The PFP Treatment and Storage Unit DWTP presented below incorporates all of the components of the PFP DWTP by reference. The discussion presented in this document identifies aspects of the training program specific to the PFP Treatment and Storage Unit. The training program includes specifications for personnel instruction through both classroom and on-the-job training. Training is developed specific to waste management duties. Hanford Facility personnel directly involved with the PFP Treatment and Storage Unit will receive training to container management practices, spill response, and emergency response. These will include, for example, training in the cementation process and training pertaining to applicable elements of WAC 173-303-330(1)(d). Applicable elements from WAC 173-303-330(1)(d) for the PFP Treatment and Storage Unit include: procedures for inspecting, repairing, and replacing facility emergency and monitoring equipment; communications and alarm systems; response to fires or explosions; and shutdown of operations.

  13. Supplemental feasibility study for remedial action for the Groundwater Operable Unit at the Chemical Plant Area of the Weldon Spring Site, Weldon Spring, Missouri

    SciTech Connect

    1999-08-06

    Site data evaluated indicate that after source removal, dilution and dispersion appear to be the primary processes that would further attenuate groundwater contaminant concentrations. On the basis of these attenuation processes, the calculations presented in Chapter 2 indicate that it would take several years to decades (approximately 60 to 150 and 14 years, respectively, for Zones 1 and 2) for TCE concentrations in Zones 1 and 2 to attenuate to the MCL (or ARAR) of 5 pg/L. The estimates for Zones 1 through 3, where the higher nitrate concentrations are clustered, indicate that it would likely take at least 80 years for nitrate concentrations to attenuate to the MCL (or ARAR) of 10 mg/L. Costs for implementing NINA for groundwater at the chemical plant area are primarily associated with those incurred for monitoring contaminant concentrations and the replacement costs for monitoring wells. Cost estimates are relatively high because a rather lengthy period of monitoring would be involved. Calculations performed to evaluate the feasibility of groundwater removal and subsequent treatment of the extracted water included determinations for the number of extraction wells needed, required number of pore volumes, and the number of years of implementation required to attain bench marks. The calculations were performed per zone of contamination, as discussed in Chapter 1. Several observations can be made about the results presented in Chapter 3 regarding Alternative 4. The first is that by looking at the results for Zones 1 and 2 evaluated under Alternative 4, one can also assess the feasibility of Alternative 7, because Alternative 7 addresses this particular subset of Alternative 4 (i.e., Zones 1 and 2). TCE contamination has been observed in Zones 1 and 2, but has not been reported in any of the remaining five zones. Nitrate, nitroaromatic compounds, and uranium have also been reported in Zones 1 and 2. The present-worth costs for implementing the pump and treat

  14. Systematic Method for Evaluating Extraction and Injection Flow Rates for 100-KR-4 and 100-HR-3 Groundwater Operable Unit Pump-and-Treat Interim Actions for Hydraulic Containment

    SciTech Connect

    Spiliotopoulos, Alexandros A.

    2013-03-20

    This document describes a systematic method to develop flow rate recommendations for Pump-and-Treat (P&T) extraction and injection wells in 100-KR-4 and 100-HR-3 Groundwater Operable Units (OU) of the Hanford Site. Flow rate recommendations are developed as part of ongoing performance monitoring and remedy optimization of the P&T interim actions to develop hydraulic contairnnent of the dissolved chromium plume in groundwater and protect the Columbia River from further discharges of groundwater from inland. This document details the methodology and data required to infer the influence of individual wells near the shoreline on hydraulic containment and river protection and develop flow rate recommendations to improve system performance and mitigate potential shortcomings of the system configuration in place.

  15. Groundwater quality in the San Fernando--San Gabriel groundwater basins, California

    USGS Publications Warehouse

    Kulongoski, Justin T.; Belitz, Kenneth

    2012-01-01

    Groundwater provides more than 40 percent of California's drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State's groundwater quality and increases public access to groundwater-quality information. The San Fernando and San Gabriel groundwater basins constitute one of the study units being evaluated.

  16. Performance of a zerovalent iron reactive barrier for the treatment of arsenic in groundwater: Part 1. Hydrogeochemical studies

    NASA Astrophysics Data System (ADS)

    Wilkin, Richard T.; Acree, Steven D.; Ross, Randall R.; Beak, Douglas G.; Lee, Tony R.

    2009-04-01

    Developments and improvements of remedial technologies are needed to effectively manage arsenic contamination in groundwater at hazardous waste sites. In June 2005, a 9.1 m long, 14 m deep, and 1.8 to 2.4 m wide (in the direction of groundwater flow) pilot-scale permeable reactive barrier (PRB) was installed at a former lead smelting facility, located near Helena, Montana (USA). The reactive barrier was designed to treat groundwater contaminated with moderately high concentrations of both As(III) and As(V). The reactive barrier was installed over a 3-day period using bio-polymer slurry methods and modified excavating equipment for deep trenching. The reactive medium was composed entirely of granular iron which was selected based on long-term laboratory column experiments. A monitoring network of approximately 40 groundwater sampling points was installed in July 2005. Monitoring results indicate arsenic concentrations > 25 mg L - 1 in wells located hydraulically upgradient of the PRB. Of 80 groundwater samples collected from the pilot-PRB, 11 samples exceeded 0.50 mg As L - 1 ; 62 samples had concentrations of arsenic at or below 0.50 mg L - 1 ; and, 24 samples were at or below the maximum contaminant level (MCL) for arsenic of 0.01 mg L - 1 . After 2 years of operation, monitoring points located within 1 m of the downgradient edge of the PRB showed significant decreases in arsenic concentrations at depth intervals impacted by the emplaced zerovalent iron. This study indicates that zerovalent iron can be effectively used to treat groundwater contaminated with arsenic given appropriate groundwater geochemistry and hydrology. The study also further demonstrates the shortcomings of hanging-wall designs. Detailed subsurface characterization data that capture geochemical and hydrogeologic variability, including a flux-based analysis, are needed for successful applications of PRB technology for arsenic remediation.

  17. Performance of a zerovalent iron reactive barrier for the treatment of arsenic in groundwater: Part 1. Hydrogeochemical studies.

    PubMed

    Wilkin, Richard T; Acree, Steven D; Ross, Randall R; Beak, Douglas G; Lee, Tony R

    2009-04-15

    Developments and improvements of remedial technologies are needed to effectively manage arsenic contamination in groundwater at hazardous waste sites. In June 2005, a 9.1 m long, 14 m deep, and 1.8 to 2.4 m wide (in the direction of groundwater flow) pilot-scale permeable reactive barrier (PRB) was installed at a former lead smelting facility, located near Helena, Montana (USA). The reactive barrier was designed to treat groundwater contaminated with moderately high concentrations of both As(III) and As(V). The reactive barrier was installed over a 3-day period using bio-polymer slurry methods and modified excavating equipment for deep trenching. The reactive medium was composed entirely of granular iron which was selected based on long-term laboratory column experiments. A monitoring network of approximately 40 groundwater sampling points was installed in July 2005. Monitoring results indicate arsenic concentrations >25 mg L(-1) in wells located hydraulically upgradient of the PRB. Of 80 groundwater samples collected from the pilot-PRB, 11 samples exceeded 0.50 mg As L(-1); 62 samples had concentrations of arsenic at or below 0.50 mg L(-1); and, 24 samples were at or below the maximum contaminant level (MCL) for arsenic of 0.01 mg L(-1). After 2 years of operation, monitoring points located within 1 m of the downgradient edge of the PRB showed significant decreases in arsenic concentrations at depth intervals impacted by the emplaced zerovalent iron. This study indicates that zerovalent iron can be effectively used to treat groundwater contaminated with arsenic given appropriate groundwater geochemistry and hydrology. The study also further demonstrates the shortcomings of hanging-wall designs. Detailed subsurface characterization data that capture geochemical and hydrogeologic variability, including a flux-based analysis, are needed for successful applications of PRB technology for arsenic remediation. PMID:19167133

  18. Groundwater and climate change: mitigating the global groundwater crisis and adapting to climate change model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To better understand the effects of climate change on global groundwater resources, the United Nations Educational, Scientific, and Cultural Organization (UNESCO) International Hydrological Programme (IHP) initiated the GRAPHIC (Groundwater Resources Assessment under the Pressures of Humanity and Cl...

  19. Modeling Irrigation Pumping and Groundwater Depletion in the High Plains Aquifer, USA

    NASA Astrophysics Data System (ADS)

    Pokhrel, Y. N.; Koirala, S.; Yamada, T.; Hanasaki, N.; Yeh, P. J.; Yoshimura, K.; Kanae, S.; Oki, T.

    2011-12-01

    Groundwater is an important source of human water use in many regions. Today, at least one-fourth of world's population rely on water drawn from underground aquifers. During the last several decades, rapid expansion of irrigated areas has led to significant increase in agricultural groundwater withdrawal. Natural dynamic equilibrium of groundwater systems (recharge = discharge) is perturbed when groundwater is artificially pumped, and if pumping exceeds recharge over large areas and prolonged period of time, progressive decrease in groundwater storage can occur which is usually termed as 'groundwater mining'. Evidence is now growing that groundwater resources have been dwindling due to excessive groundwater mining, particularly in semi-arid regions where most croplands with intensive irrigation are located. Here, we provide the first model-based study of the impact of irrigation pumping on groundwater depletion by using an integrated model HIGW-MAT developed by incorporating human impact modules (reservoir operation, irrigation, water withdrawal) and a fully dynamic groundwater representation into the state-of-the-art land surface model called MATSIRO (Minimal Advanced Treatments of Surface Interaction and Runoff). Total water requirements of a grid cell (domestic, industrial, and agricultural) are withdrawn from surface and/or sub-surface sources based on water availability. When the surface water sources such as river and medium-sized reservoirs deplete below a prescribed threshold, water is pumped from groundwater reservoir. The groundwater scheme is an unconfined aquifer model in which soil column is separated into continuously interacting saturated and unsaturated zones by the water table. Thus, the model simulates the flow of water taking into account anthropogenic water regulation and groundwater pumping and return flow of anthropogenic water use. Simulations are conducted at 1° × 1° (longitude and latitude) spatial resolution at the global scale. The

  20. The impacts of low-cost treatment options upon scale formation potential in remote communities reliant on hard groundwaters. A case study: Northern Territory, Australia.

    PubMed

    Kinsela, Andrew S; Jones, Adele M; Collins, Richard N; Waite, T David

    2012-02-01

    The majority of small, remote communities within the Northern Territory (NT) in Central Australia are reliant on groundwater as their primary supply of domestic, potable water. Saturation indices for a variety of relevant minerals were calculated using available thermodynamic speciation codes on collected groundwater data across the NT. These saturation indices were used to assess the theoretical formation of problematic mineral-scale, which manifests itself by forming stubborn coatings on domestic appliances and fixtures. The results of this research show that 63% of the measured sites within the NT have the potential to form calcium carbonate (CaCO(3)) scale, increasing to 91% in arid, central regions. The data also suggests that all groundwaters are over-saturated with respect to amorphous calcium-bridged ferric-silica polymers, based on the crystalline mineral index (Ca(3)Fe(2)Si(3)O(12)), although the quantitative impact of this scale is limited by low iron concentrations. An assessment of possible low-cost/low-technology management options was made, including; lowering the temperature of hot-water systems, diluting groundwater with rainwater and modifying the pH of the source water. Source water pH modification (generally a reduction to pH 7.0) was shown to clearly alleviate potential carbonate-based scale formation, over and above the other two options, albeit at a greater technical and capital expense. Although low-cost/low-technology treatment options are unlikely to remove severe scale-related issues, their place in small, remote communities with minor scale problems should be investigated further, owing to the social, technical and capital barriers involved with installing advanced treatment plants (e.g. reverse osmosis) in such locations. PMID:22225826

  1. Wetland survey of the X-10 Bethel Valley and Melton Valley groundwater operable units at Oak Ridge National Labortory Oak Ridge, Tennessee

    SciTech Connect

    Rosensteel, B.A.

    1996-03-01

    Executive Order 11990, Protection of Wetlands, (May 24, 1977) requires that federal agencies avoid, to the extent possible, adverse impacts associated with the destruction and modification of wetlands and that they avoid direct and indirect support of wetlands development when there is a practicable alternative. In accordance with Department of Energy (DOE) Regulations for Compliance with Floodplains and Wetlands Environmental Review Requirements (Subpart B, 10 CFR 1022.11), surveys for wetland presence or absence were conducted in both the Melton Valley and the Bethel Valley Groundwater Operable Units (GWOU) on the DOE Oak Ridge Reservation (ORR) from October 1994 through September 1995. As required by the Energy and Water Development Appropriations Act of 1992, wetlands were identified using the criteria and methods set forth in the Wetlands Delineation Manual (Army Corps of Engineers, 1987). Wetlands were identified during field surveys that examined and documented vegetation, soils, and hydrologic evidence. Most of the wetland boundary locations and wetland sizes are approximate. Boundaries of wetlands in Waste Area Grouping (WAG) 2 and on the former proposed site of the Advanced Neutron Source in the upper Melton Branch watershed were located by civil survey during previous wetland surveys; thus, the boundary locations and areal sizes in these areas are accurate. The wetlands were classified according to the system developed by Cowardin et al. (1979) for wetland and deepwater habitats of the United States. A total of 215 individual wetland areas ranging in size from 0.002 ha to 9.97 ha were identified in the Bethel Valley and Melton Valley GWOUs. The wetlands are classified as palustrine forested broad-leaved deciduous (PFO1), palustrine scrub-shrub broad-leaved deciduous (PSS1), and palustrine persistent emergent (PEM1).

  2. Arkansas Groundwater-Quality Network

    USGS Publications Warehouse

    Pugh, Aaron L.; Jackson, Barry T.; Miller, Roger

    2014-01-01

    Arkansas is the fourth largest user of groundwater in the United States, where groundwater accounts for two-thirds of the total water use. Groundwater use in the State increased by 510 percent between 1965 and 2005 (Holland, 2007). The Arkansas Groundwater-Quality Network is a Web map interface (http://ar.water.usgs.gov/wqx) that provides rapid access to the U.S. Geological Survey’s (USGS) National Water Information System (NWIS) and the U.S. Environmental Protection Agency’s (USEPA) STOrage and RETrieval (STORET) databases of ambient water information. The interface enables users to perform simple graphical analysis and download selected water-quality data.

  3. Groundwater: Illinois' Buried Treasure. Education Activity Guide.

    ERIC Educational Resources Information Center

    Environmental Education Association of Illinois, Chicago.

    Groundwater is an extremely valuable resource that many feel has been too long neglected and taken for granted. There is growing recognition in Illinois and throughout the United States that comprehensive groundwater protection measures are vital. Illinois embarked on a course in protecting groundwater resources with the passage of the Illinois…

  4. 129Iodine Desorption from Resin, Activated Carbon, and Filtercake Waste Generated from the F- and H-Area Water Treatment Units

    SciTech Connect

    Kaplan, D.I.

    2000-11-28

    The objective of this study was to quantify 129I desorption of six waste materials in acidic and alkaline environments, simulating trench and cementitious disposal conditions. These data will be used in future performance assessment calculations to evaluate subsurface waste disposal at the SRS. Since performance assessment considers dose thousands of years in the future, it was also necessary to evaluate how 129I desorption changed as a function of time. Laboratory column and batch studies were conducted with waste materials collected from the F-Area and H-Area Groundwater Treatment Units, operated by the Environmental Restoration Division. Thirteen liters of effluent were passed through each column. This volume represents about 1000 years worth of water passing through concrete and 100 years worth of water passing through soil.

  5. Estimating global groundwater withdrawal and depletion using an integrated hydrological model, GRACE, and in situ observations

    NASA Astrophysics Data System (ADS)

    Pokhrel, Y. N.; Koirala, S.; Hanasaki, N.; Yeh, P. J.; Kanae, S.; Oki, T.

    2012-12-01

    In the past several decades extensive use of groundwater, particularly for irrigation, has led to rapid groundwater depletion in many regions. This has not only affected the terrestrial water cycle but also resulted in global sea level rise because a large portion of unsustainably pumped groundwater eventually ends up in the ocean. Therefore, monitoring groundwater resources and their use has become increasingly important. While in situ observations are invaluable for assessing and monitoring groundwater availability, global models and satellite-based observations provide further insights into groundwater dynamics in regions where observations are scarce. In this study, we highlight the major hotspots of global groundwater depletion and the consequent sea level change by using an integrated modeling framework. The model was developed by incorporating a dynamic groundwater scheme and a pumping scheme into a global land surface model (MATSIRO: Minimal Advanced Treatments of Surface Interaction and Runoff) which also accounts for the effects of major human activities (e.g., reservoir operation, irrigation, and water withdrawal) on the terrestrial water cycle. All components of the model are fully coupled and the model tracks the flow of water taking into account the withdrawals of water for agricultural, domestic, and industrial uses from various sources such as river networks, medium-sized reservoirs, and groundwater reservoir. Using model results, GRACE measurement, and ground-based observations by the United States Geological Survey, we demonstrate that groundwater has been declining in many regions with a particular focus on the major aquifers in the United States. In the region overlying the High Plains aquifer, which is extensively irrigated mainly by using groundwater, the simulated groundwater withdrawal of ~23 km3/yr agrees well with the observational record of ~24 km3/yr for circa 2000. Moreover, corresponding closely with the USGS water level observations

  6. Effects of Hydrogen Peroxide on Dental Unit Biofilms and Treatment Water Contamination

    PubMed Central

    Lin, Shih-Ming; Svoboda, Kathy K.H.; Giletto, Anthony; Seibert, Jeff; Puttaiah, Raghunath

    2011-01-01

    Objectives: To study effects of various concentrations of hydrogen peroxide on mature waterline biofilms and in controlling planktonic (free-floating) organisms in simulated dental treatment water systems; and to study in vitro the effects of 2%, 3%, and 7% hydrogen peroxide on the removal of mature biofilms and inorganic compounds in dental waterlines. Methods: Four units of an automated dental unit water system simulation device was used for 12 weeks. All units were initially cleaned to control biofilms and inorganic deposits. H2O2 at concentrations of 1%, 2%, 3% was used weekly for periodic cleaning in three treatment group units (units 1, 2 & 3), with 0.05%, 0.15% and 0.25% H2O2 in municipal water used as irrigant respectively. The control unit (unit 4) did not have weekly cleanings and used municipal water as irrigant. Laser Scanning Confocal Microscopy and Scanning Electron Microscopy were used to study deposits on lines, and weekly heterotrophic plate counts done to study effluent water contamination. A 24 hour in vitro challenge test with 7%, 3% and 2% H2O2 on mature biofilms was conducted using harvested waterlines to study biofilm and inorganic deposit removal. Results: Heterotrophic plate counts of effluent water showed that the control unit reached contamination levels in excess of 400,000 CFU/mL while all treatment units showed contamination levels <500 CFU/mL through most of the 12 weeks. All treatment units showed varying levels of biofilm and inorganic deposit control in this short 12 week study. The in vitro challenge test showed although there was biofilm control, there was no eradication even when 7% H2O2 was used for 24 hours. Conclusions: 2% H2O2 used as a periodic cleaner, and diluted to 0.05% in municipal water for irrigation was beneficial in controlling biofilm and planktonic contamination in dental unit water systems. However, to remove well established biofilms, it may take more than 2 months when initial and multiple periodic cleanings

  7. Annual report for RCRA groundwater monitoring projects at Hanford Site facilities for 1995

    SciTech Connect

    Hartman, M.J.

    1996-02-01

    This report presents the annual hydrogeologic evaluation of 19 Resource Conservation and Recovery Act of 1976 facilities and 1 nonhazardous waste facility at the US Department of Energy`s Hanford Site. Although most of the facilities no longer receive dangerous waste, a few facilities continue to receive dangerous waste constituents for treatment, storage, or disposal. The 19 Resource Conservation and Recovery Act facilities comprise 29 waste management units. Nine of the units are monitored under groundwater quality assessment status because of elevated levels of contamination indicator parameters. The impact of those units on groundwater quality, if any, is being investigated. If dangerous waste or waste constituents have entered groundwater, their concentration profiles, rate, and extent of migration are evaluated. Groundwater is monitored at the other 20 units to detect leakage, should it occur. This report provides an interpretation of groundwater data collected at the waste management units between October 1994 and September 1995. Groundwater quality is described for the entire Hanford Site. Widespread contaminants include nitrate, chromium, carbon tetrachloride, tritium, and other radionuclides.

  8. Method to Remove Uranium/Vanadium Contamination from Groundwater

    SciTech Connect

    Metzler, Donald R.; Morrison Stanley

    2004-07-27

    A process for removing uranium/vanadium-based contaminants from groundwater using a primary in-ground treatment media and a pretreatment media that chemically adjusts the groundwater contaminant to provide for optimum treatment by the primary treatment media.

  9. Method to remove uranium/vanadium contamination from groundwater

    DOEpatents

    Metzler, Donald R.; Morrison, Stanley

    2004-07-27

    A process for removing uranium/vanadium-based contaminants from groundwater using a primary in-ground treatment media and a pretreatment media that chemically adjusts the groundwater contaminant to provide for optimum treatment by the primary treatment media.

  10. Comparison of biostimulation versus bioaugmentation with bacterial strain PM1 for treatment of groundwater contaminated with methyl tertiary butyl ether (MTBE).

    PubMed

    Smith, Amanda E; Hristova, Krassimira; Wood, Isaac; Mackay, Doug M; Lory, Ernie; Lorenzana, Dale; Scow, Kate M

    2005-03-01

    Widespread contamination of groundwater by methyl tertiary butyl ether (MTBE) has triggered the exploration of different technologies for in situ removal of the pollutant, including biostimulation of naturally occurring microbial communities or bioaugmentation with specific microbial strains known to biodegrade the oxygenate. After laboratory studies revealed that bacterial strain PM1 rapidly and completely biodegraded MTBE in groundwater sediments, the organism was tested in an in situ field study at Port Hueneme Naval Construction Battalion Center in Oxnard, California. Two pilot test plots (A and B) in groundwater located down-gradient from an MTBE source were intermittently sparged with pure oxygen. Plot B was also inoculated with strain PM1. MTBE concentrations up-gradient from plots A and B initially varied temporally from 1.5 to 6 mg MTBE/L. Six months after treatment began, MTBE concentrations in monitoring wells down-gradient from the injection bed decreased substantially in the shallow zone of the groundwater in plots A and B, thus even in the absence of the inoculated strain PM1. In the deeper zone, downstream MTBE concentrations also decreased in plot A and to a lesser extent in plot B. Difficulties in delivery of oxygen to the deeper zone of plot B, evidenced by low dissolved oxygen concentrations, were likely responsible for low rates of MTBE removal at that location. We measured the survival and movement of strain PM1 in groundwater samples using two methods for detection of DNA sequences specific to strain PM1: TaqMan quantitative polymerase chain reaction, and internal transcribed spacer region analysis. A naturally occurring bacterial strain with > 99% 16S rDNA sequence similarity to strain PM1 was detected in groundwater collected at various locations at Port Hueneme, including outside the plots where the organism was inoculated. Addition of oxygen to naturally occurring microbial populations was sufficient to stimulate MTBE removal at this site

  11. Goals and Basic Units of Instruction for Treatment Media Courses for the Preparation of Occupational Therapists.

    ERIC Educational Resources Information Center

    Preitz, Clarence Harold

    The problem of this research was to ascertain the essential major goals for university level treatment media courses for the professional preparation of occupational therapists and to determine units of instruction to fulfill these goals. A pretested survey instrument, systematic observations, and interviews were used to collect data from the…

  12. Official Satire in Propaganda: The Treatment of the United States in the GDR's "Eulenspiegel."

    ERIC Educational Resources Information Center

    Bytwerk, Randall L.

    1989-01-01

    Examines 102 issues (published in 1985 and 1986) of the "Eulenspiegel," the only magazine in the German Democratic Republic (GDR) devoted to humor and satire. Focuses on the "Eulenspiegel's" treatment of the United States to determine the nature of that satire, its purposes, and its effectiveness. (MM)

  13. The Relative Effectiveness of 10 Adolescent Substance Abuse Treatment Programs in the United States. Technical Report

    ERIC Educational Resources Information Center

    Morral, Andrew R.; McCaffrey, Daniel F.; Ridgeway, Greg; Mukherji, Arnab; Beighley, Christopher

    2006-01-01

    Each year, substance abuse treatment programs in the United States record approximately 150,000 admissions of youths under the age of 18. Nevertheless, little is known about the effectiveness of the types of community-based services typically available to youths and their families. Recognizing the need for better information on the effectiveness…

  14. The Interactive Seminar: An Educational Approach for Voluntary HIV Testing in a Drug Dependence Treatment Unit.

    ERIC Educational Resources Information Center

    Sedhom, Laila; And Others

    1994-01-01

    A survey of 118 male patients in a drug dependence treatment unit before and after an interactive seminar with a nonjudgmental professional showed that seminar participants, especially intravenous drug users, had higher rates of voluntary HIV testing than nonparticipants. Drug users who completed detoxification and attended the seminar also had…

  15. 76 FR 60390 - Irradiation Treatment; Location of Facilities in the Southern United States

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-29

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF AGRICULTURE... (APHIS) of the U.S. Department of Agriculture administers these regulations. Irradiation Treatment in... of tropical fruits from Thailand in either Thailand or the United States. Fruit from India...

  16. Household willingness to pay for azithromycin treatment for trachoma control in the United Republic of Tanzania.

    PubMed Central

    Frick, Kevin D.; Lynch, Matthew; West, Sheila; Munoz, Beatriz; Mkocha, Harran A.

    2003-01-01

    OBJECTIVE: Household willingness to pay for treatment provides important information for programme planning. We tested for relationships between socioeconomic status, risk of trachoma, perceptions of the effects of azithromycin, and the household willingness to pay for future mass treatment with azithromycin. METHODS: We surveyed 394 households in 6 villages located in central United Republic of Tanzania regarding their willingness to pay for future azithromycin treatment. A random sample of households with children under 8 years of age was selected and interviewed following an initial treatment programme in each village. Data were gathered on risk factors for trachoma, socioeconomic status, and the perceived effect of the initial azithromycin treatment. Ordered probit regression analysis was used to test for statistically significant relationships. FINDINGS: 38% of responding households stated that they would not be willing to pay anything for future azithromycin treatment, although they would be willing to participate in the treatment. A proxy for cash availability was positively associated with household willingness to pay for future antibiotic treatment. Cattle ownership (a risk factor) and being a household headed by a female not in a polygamous marriage (lower socioeconomic status) were associated with a lower willingness to pay for future treatment. A perceived benefit from the initial treatment was marginally associated with a willingness to pay a higher amount. CONCLUSIONS: As those at greatest risk of active trachoma indicated the lowest willingness to pay, imposing a cost recovery fee for azithromycin treatment would likely reduce coverage and could prevent control of the disease at the community level. PMID:12751418

  17. Groundwater-quality data in seven GAMA study units: results from initial sampling, 2004-2005, and resampling, 2007-2008, of wells: California GAMA Program Priority Basin Project

    USGS Publications Warehouse

    Kent, Robert; Belitz, Kenneth; Fram, Miranda S.

    2014-01-01

    The Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) Program was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The GAMA-PBP began sampling, primarily public supply wells in May 2004. By the end of February 2006, seven (of what would eventually be 35) study units had been sampled over a wide area of the State. Selected wells in these first seven study units were resampled for water quality from August 2007 to November 2008 as part of an assessment of temporal trends in water quality by the GAMA-PBP. The initial sampling was designed to provide a spatially unbiased assessment of the quality of raw groundwater used for public water supplies within the seven study units. In the 7 study units, 462 wells were selected by using a spatially distributed, randomized grid-based method to provide statistical representation of the study area. Wells selected this way are referred to as grid wells or status wells. Approximately 3 years after the initial sampling, 55 of these previously sampled status wells (approximately 10 percent in each study unit) were randomly selected for resampling. The seven resampled study units, the total number of status wells sampled for each study unit, and the number of these wells resampled for trends are as follows, in chronological order of sampling: San Diego Drainages (53 status wells, 7 trend wells), North San Francisco Bay (84, 10), Northern San Joaquin Basin (51, 5), Southern Sacramento Valley (67, 7), San Fernando–San Gabriel (35, 6), Monterey Bay and Salinas Valley Basins (91, 11), and Southeast San Joaquin Valley (83, 9). The groundwater samples were analyzed for a large number of synthetic organic constituents (volatile organic compounds [VOCs], pesticides, and pesticide degradates), constituents of special interest (perchlorate, N

  18. Waste Isolation Pilot Plant Groundwater Protection Management Program Plan

    SciTech Connect

    Washington Regulatory and Environmental Services

    2005-07-01

    The DOE established the Groundwater Monitoring Program (GMP) (WP 02-1) to monitor groundwater resources at WIPP. In the past, the GMP was conducted to establish background data of existing conditions of groundwater quality and quantity in the WIPP vicinity, and to develop and maintain a water quality database as required by regulation. Today the GMP is conducted consistent with 204.1.500 NMAC (New MexicoAdministrative Code), "Adoption of 40 CFR [Code of Federal Regulations] Part 264,"specifically 40 CFR §264.90 through §264.101. These sections of 20.4.1 NMAC provide guidance for detection monitoring of groundwater that is, or could be, affected by waste management activities at WIPP. Detection monitoring at WIPP is designed to detect contaminants in the groundwater long before the general population is exposed. Early detection will allow cleanup efforts to be accomplished before any exposure to the general population can occur. Title 40 CFR Part 264, Subpart F, stipulates minimum requirements of Resource Conservation and Recovery Act of 1976 (42 United States Code [U.S.C.] §6901 et seq.) (RCRA) groundwater monitoring programs including the number and location of monitoring wells; sampling and reporting schedules; analytical methods and accuracy requirements; monitoring parameters; and statistical treatment of monitoring data. This document outlines how WIPP intends to protect and preserve groundwater within the WIPP Land Withdrawal Area (WLWA). Groundwater protection is just one aspect of the WIPP environmental protection effort. An overview of the entire environmental protection effort can be found in DOE/WIPP 99-2194, Waste Isolation Pilot Plant Environmental Monitoring Plan. The WIPP GMP is designed to statistically determine if any changes are occurring in groundwater characteristics within and surrounding the WIPP facility. If a change is noted, the cause will then be determined and the appropriate corrective action(s) initiated.

  19. Field Test Report: Preliminary Aquifer Test Characterization Results for Well 299-W15-225: Supporting Phase I of the 200-ZP-1 Groundwater Operable Unit Remedial Design

    SciTech Connect

    Spane, Frank A.; Newcomer, Darrell R.

    2009-09-23

    This report examines the hydrologic test results for both local vertical profile characterization and large-scale hydrologic tests associated with a new extraction well (well 299-W15-225) that was constructed during FY2009 for inclusion within the future 200-West Area Groundwater Treatment System that is scheduled to go on-line at the end of FY2011. To facilitate the analysis of the large-scale hydrologic test performed at newly constructed extraction well 299-W15-225 (C7017; also referred to as EW-1 in some planning documents), the existing 200-ZP-1 interim pump-and-treat system was completely shut-down ~1 month before the performance of the large-scale hydrologic test. Specifically, this report 1) applies recently developed methods for removing barometric pressure fluctuations from well water-level measurements to enhance the detection of hydrologic test and pump-and-treat system effects at selected monitor wells, 2) analyzes the barometric-corrected well water-level responses for a preliminary determination of large-scale hydraulic properties, and 3) provides an assessment of the vertical distribution of hydraulic conductivity in the vicinity of newly constructed extraction well 299-W15-225. The hydrologic characterization approach presented in this report is expected to have universal application for meeting the characterization needs at other remedial action sites located within unconfined and confined aquifer systems.

  20. Arsenate and Arsenite Sorption on Magnetite: Relations to Groundwater Arsenic Treatment Using Zerovalent Iron and Natural Attenuation

    EPA Science Inventory

    Magnetite (Fe3O4) is a zerovalent iron corrosion product; it is also formed in natural soil and sediment. Sorption of arsenate (As(V)) and arsenite (As(III)) on magnetite is an important process of arsenic removal from groundwater using zerovalent iron-based permeable reactive ba...

  1. Final construction and testing of an experimental sprinkler/groundwater treatment system for proposed use by the village of Utica, Nebraska.

    SciTech Connect

    2005-06-17

    The testing described above demonstrates that the experimental sprinkler designed by Argonne could be successfully, and safely, used by the Village of Utica for irrigation of the town's playing fields, using contaminated (by carbon tetrachloride) groundwater from the shallow aquifer beneath the town. Routine operation of the sprinkler within the range of parameters identified by the testing program would effectively reduce carbon tetrachloride concentrations in the discharged spray reaching the ground to levels below the MCL (5 {micro}g/l). CCC/USDA and Argonne propose to test use of the experimental sprinkler by the Village of Utica during the next (Summer 2001) growing season, under Argonne supervision. Water will be supplied from the well to the sprinkler drive unit using a temporary, flexible (high-pressure hose) connection. Argonne will provide training to Village staff in the setup and use of the sprinkler, and will conduct periodic monitoring (proposed biweekly, initially) of the watering operations and sampling and analysis of the spray discharge from the unit, to ensure that the specified groundwater cleanup performance of the sprinkler system (to carbon tetrachloride values <5 {micro}g/L) is maintained. If testing of the sprinkler in this manner proves successful during 2001, CCC/USDA will seek to permanently transfer ownership and operation responsibilities for the sprinkler to the Utica Village Board.

  2. The Association of Arsenic With Redox Conditions, Depth, and Ground-Water Age in the Glacial Aquifer System of the Northern United States

    USGS Publications Warehouse

    Thomas, Mary Ann

    2007-01-01

    More than 800 wells in the glacial aquifer system of the Northern United States were sampled for arsenic as part of U.S. Geological Survey National Water-Quality Assessment (NAWQA) studies during 1991-2003. Elevated arsenic concentrations (greater than or equal to 10 micrograms per liter) were detected in 9 percent of samples. Elevated arsenic concentrations were associated with strongly reducing conditions. Of the samples classified as iron reducing or sulfate reducing, arsenic concentrations were elevated in 19 percent. Of the methanogenic samples, arsenic concentrations were elevated in 45 percent. In contrast, concentrations of arsenic were elevated in only 1 percent of oxic samples. Arsenic concentrations were also related to ground-water age. Elevated arsenic concentrations were detected in 34 percent of old waters (recharged before 1953) as compared to 4 percent of young waters (recharged since 1953). For samples classified as both old and methanogenic, elevated arsenic concentrations were detected in 62 percent of samples, as compared to 1 percent for samples classified as young and oxic. Arsenic concentrations were also correlated with well depth and concentrations of several chemical constituents, including (1) constituents linked to redox processes and (2) anions or oxyanions that sorb to iron oxides. Observations from the glacial aquifer system are consistent with the idea that the predominant source of arsenic is iron oxides and the predominant mechanism for releasing arsenic to the ground water is reductive desorption or reductive dissolution. Arsenic is also released from iron oxides under oxic conditions, but on a more limited basis and at lower concentrations. Logistic regression was used to investigate the relative significance of redox, ground-water age, depth, and other water-quality constituents as indicators of elevated arsenic concentrations in the glacial aquifer system. The single variable that explained the greatest amount of variation in

  3. 40 CFR 257.22 - Ground-water monitoring systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Ground-water monitoring systems. 257... Waste Disposal Units Ground-Water Monitoring and Corrective Action § 257.22 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of a sufficient number...

  4. 40 CFR 257.22 - Ground-water monitoring systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Ground-water monitoring systems. 257... Waste Disposal Units Ground-Water Monitoring and Corrective Action § 257.22 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of a sufficient number...

  5. 40 CFR 257.22 - Ground-water monitoring systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Ground-water monitoring systems. 257... Waste Disposal Units Ground-Water Monitoring and Corrective Action § 257.22 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of a sufficient number...

  6. 40 CFR 257.22 - Ground-water monitoring systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Ground-water monitoring systems. 257... Waste Disposal Units Ground-Water Monitoring and Corrective Action § 257.22 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of a sufficient number...

  7. 40 CFR 257.22 - Ground-water monitoring systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Ground-water monitoring systems. 257.22... Disposal Units Ground-Water Monitoring and Corrective Action § 257.22 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of a sufficient number of...

  8. Addendum for the Phase II Groundwater Flow Model of Corrective Action Unit 98: Frenchman Flat, NevadaTest Site, Nye County, Nevada, Revision 0 (page changes)

    SciTech Connect

    John McCord

    2007-05-01

    This document, which makes changes to Phase II Groundwater Flow Model of Corrective Action Unit 98: Frenchman Flat, Nevada Test Site, Nye County, Nevada, S-N/99205--074, Revision 0 (May 2006) was prepared to address review comments on this final document provided by the Nevada Division of Environmental Protection (NDEP) in a letter dated June 20, 2006. The document includes revised pages that address NDEP review comments and comments from other document users. Change bars are included on these pages to identify where the text was revised. In addition to the revised pages, the following clarifications are made: • Section 6.0 Conceptual Model Uncertainty Analyses. Please note that in this section figures showing the observed versus simulated well head (Figures 6-1, 6-5, 6-7, 6-16, 6-28, 6-30, 6-32, 6-34, 6-37, 6-42, 6-47, 6-52, 6-57, 6-62, 6-71, and 6-86) have a vertical break in scale on the y axis. • Section 7.0 Parameter Sensitivity Analysis. In Section 7.2, the parameter perturbation analysis defines two components of the objective function PHI. These two components include the WELL component that represents the head portion of the objective function as measured in wells and the FLUX component that represents the lateral boundary flux portion of the objective function. In the text and figures in Section 7.2, the phrases “well portion of the objective function” and “head portion of the objective function” are used interchangeably in discussions of the WELL component of the objective function.

  9. Groundwater Science

    NASA Astrophysics Data System (ADS)

    McKenna, Sean A.

    A good introductory groundwater textbook must strike a delicate balance in presenting the basics of the physical, chemical, geological, mathematical, and engineering aspects of the groundwater field without being too lengthy or overly detailed. Charles Fitts states that his motivation for writing Groundwater Science was to be able to “…teach concepts and quantitative analyses with a clear, lean, but thorough book.” He has succeeded in striking this balance of having just the right amount of information, and has met his goals of producing a concise book that can be used to teach the concepts and analyses necessary for the study of groundwater.Overall, Groundwater Science would serve well as the text for an introductory groundwater course at the college senior or first-year graduate level. The author and the publisher have made excellent use of two-color, gray and blue-scale images throughout the book. The graphics are crisp and explanatory. Data sets needed to work some of the problems in the book are available as text files from its Web site (http://www.academicpress.com/groundwater). I found these files to be complete and easy to understand. The references are up to date and point the reader to additional information across a wide range of groundwater issues, and also provide a number of examples to illustrate different points made in the book.

  10. Population-level differences in revascularization treatment and outcomes among various United States subpopulations

    PubMed Central

    Graham, Garth; Xiao, Yang-Yu Karen; Rappoport, Dan; Siddiqi, Saima

    2016-01-01

    Despite recent general improvements in health care, significant disparities persist in the cardiovascular care of women and racial/ethnic minorities. This is true even when income, education level, and site of care are taken into consideration. Possible explanations for these disparities include socioeconomic considerations, elements of discrimination and racism that affect socioeconomic status, and access to adequate medical care. Coronary revascularization has become the accepted and recommended treatment for myocardial infarction (MI) today and is one of the most common major medical interventions in the United States, with more than 1 million procedures each year. This review discusses recent data on disparities in co-morbidities and presentation symptoms, care and access to medical resources, and outcomes in revascularization as treatment for acute coronary syndrome, looking especially at women and minority populations in the United States. The data show that revascularization is used less in both female and minority patients. We summarize recent data on disparities in co-morbidities and presentation symptoms related to MI; access to care, medical resources, and treatments; and outcomes in women, blacks, and Hispanics. The picture is complicated among the last group by the many Hispanic/Latino subgroups in the United States. Some differences in outcomes are partially explained by presentation symptoms and co-morbidities and external conditions such as local hospital capacity. Of particular note is the striking differential in both presentation co-morbidities and mortality rates seen in women, compared to men, especially in women ≤ 55 years of age. Surveillance data on other groups in the United States such as American Indians/Alaska Natives and the many Asian subpopulations show disparities in risk factors and co-morbidities, but revascularization as treatment for MI in these populations has not been adequately studied. Significant research is required to

  11. Population-level differences in revascularization treatment and outcomes among various United States subpopulations.

    PubMed

    Graham, Garth; Xiao, Yang-Yu Karen; Rappoport, Dan; Siddiqi, Saima

    2016-01-26

    Despite recent general improvements in health care, significant disparities persist in the cardiovascular care of women and racial/ethnic minorities. This is true even when income, education level, and site of care are taken into consideration. Possible explanations for these disparities include socioeconomic considerations, elements of discrimination and racism that affect socioeconomic status, and access to adequate medical care. Coronary revascularization has become the accepted and recommended treatment for myocardial infarction (MI) today and is one of the most common major medical interventions in the United States, with more than 1 million procedures each year. This review discusses recent data on disparities in co-morbidities and presentation symptoms, care and access to medical resources, and outcomes in revascularization as treatment for acute coronary syndrome, looking especially at women and minority populations in the United States. The data show that revascularization is used less in both female and minority patients. We summarize recent data on disparities in co-morbidities and presentation symptoms related to MI; access to care, medical resources, and treatments; and outcomes in women, blacks, and Hispanics. The picture is complicated among the last group by the many Hispanic/Latino subgroups in the United States. Some differences in outcomes are partially explained by presentation symptoms and co-morbidities and external conditions such as local hospital capacity. Of particular note is the striking differential in both presentation co-morbidities and mortality rates seen in women, compared to men, especially in women ≤ 55 years of age. Surveillance data on other groups in the United States such as American Indians/Alaska Natives and the many Asian subpopulations show disparities in risk factors and co-morbidities, but revascularization as treatment for MI in these populations has not been adequately studied. Significant research is required to

  12. Treatment tests for ex situ removal of chromate, nitrate, and uranium (VI) from Hanford (100-HR-3) groundwater. Final report

    SciTech Connect

    Beck, M.A.; Duncan, J.B.

    1993-11-15

    This report describes batch and anion exchange column laboratory-scale studies investigating ex situ methods to remove chromate (chromium [VI]), nitrate (NO{sub 3}), and uranium (present as uranyl (uranium [VI]) carbonato anionic species) from contaminated Hanford Site groundwaters. The technologies investigated include chemical precipitation or coprecipitation to remove chromate and uranium, and anion exchange to remove chromate, uranium, and nitrate. The technologies investigated were specified in the 100-HR-3 Groundwater Treatability Test Plan (DOE-RL 1993). The goal of these tests was to determine the best method to remove selected contaminants to below the concentration of the project performance goals. The raw data and observations made during these tests can be found in the Westinghouse Hanford Company (WHC) laboratory notebooks (Beck 1992, Herting 1993). The method recommended for future study is anion exchange with Dowex 21K resin.

  13. Effect of Breast Volume on Treatment Reproducibility on a Tomotherapy Unit in the Treatment of Breast Cancer

    SciTech Connect

    Offerman, Shannon; Lamba, Michael; Lavigne, Ruth

    2011-06-01

    Purpose: To determine whether the volume of a patient's breast is correlated with reliable daily setup in treatment of breast cancer with a helical tomotherapy treatment unit. Methods and Materials: Thirty-six consecutive patients with breast cancer were treated on a helical tomotherapy unit. During simulation, kilovoltage CT images were obtained for treatment planning. These were fused with daily megavoltage CT scans, and after setup based on skin marks and laser alignment the necessary shifts were carried out. The magnitude of daily shifts (in millimeters) was retrospectively obtained from the daily image fusions, and the breast volume was obtained from the treatment plan. A total of 873 fusion scans were reviewed. Random error for absolute and directional daily shifts was evaluated for correlation to volume. Variation over time was also evaluated. Results: Mean (SD) random shift for all patients in the lateral, longitudinal, and vertical directions was 2.7 (2.0), 3.1 (1.5), and 3.2 (2.6) mm, respectively. Mean (SD) absolute distance shifted was 6.0 (3.5) mm. There was no significant correlation between mean absolute or mean directional daily shift and breast volume (0.08, 0.08, 0.22, and 0.07, respectively). There was no correlation between setup variation and time. Conclusions: In this cohort, there was no correlation between breast volume and degree of daily shift. There was no correlation between time course and setup variation. Therefore, setup variation does not improve or degrade with repeated treatment setups.

  14. Groundwater-quality data in the Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts study unit, 2008-2010--Results from the California GAMA Program

    USGS Publications Warehouse

    Mathany, Timothy M.; Wright, Michael T.; Beuttel, Brandon S.; Belitz, Kenneth

    2012-01-01

    Groundwater quality in the 12,103-square-mile Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts (CLUB) study unit was investigated by the U.S. Geological Survey (USGS) from December 2008 to March 2010, as part of the California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and Assessment (GAMA) Program's Priority Basin Project (PBP). The GAMA-PBP was developed in response to the California Groundwater Quality Monitoring Act of 2001 and is being conducted in collaboration with the SWRCB and Lawrence Livermore National Laboratory (LLNL). The CLUB study unit was the twenty-eighth study unit to be sampled as part of the GAMA-PBP. The GAMA CLUB study was designed to provide a spatially unbiased assessment of untreated-groundwater quality in the primary aquifer systems, and to facilitate statistically consistent comparisons of untreated-groundwater quality throughout California. The primary aquifer systems (hereinafter referred to as primary aquifers) are defined as parts of aquifers corresponding to the perforation intervals of wells listed in the California Department of Public Health (CDPH) database for the CLUB study unit. The quality of groundwater in shallow or deep water-bearing zones may differ from the quality of groundwater in the primary aquifers; shallow groundwater may be more vulnerable to surficial contamination. In the CLUB study unit, groundwater samples were collected from 52 wells in 3 study areas (Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts) in San Bernardino, Riverside, Kern, San Diego, and Imperial Counties. Forty-nine of the wells were selected by using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells), and three wells were selected to aid in evaluation of water-quality issues (understanding wells). The groundwater samples were analyzed for organic constituents (volatile

  15. Effects of dried wastewater-treatment sludge application on ground-water quality in South Dade County, Florida

    USGS Publications Warehouse

    Howie, Barbara

    1992-01-01

    Four test fields in the south Dade agricultural area were studied to determine the effects of sludge application on ground-water quality. Two fields had been cultivated for 10 years or more, and two had not been farmed for at least 10 years. The fields were representative of the area's two soil types (Rockdale and Perrine marl) and two major crop types (row crops and groves). Before the application of sludge, wells upgradient of, within, and downgradient of each field were sampled for possible sludge contaminants at the end of wet and dry seasons. Municipal wastewater treatment sludge from the Dade County Water and Sewe Authority Department was then applied to the fields at varying application rates. The wells at each field were sampled over a 2-year period under different hydrologic conditions for possible sludge-related constituents (specific conductance, pH, alkalinity, nitrogen, phosphorus, total organic carbon, copper, iron, magnesium, manganese, potassium, zinc, arsenic, cadmium, chloride, chromium, lead, mercury, nickel, and sodium). Comparisons were made between water quality in the vicinity of the test fields and Florida Department of Environmental Regulation primary and secondary drinking-water regulations, an between water quality upgradient of, beneath, and downgradient of the fields. Comparisons between presludge and postsludge water quality did not indicate any improvement because of retention of agrichemicals by the sludge nor did they indicate any deterioration because of leaching from the sludge. Comparisons of water quality upgradient of the fields to water quality beneath and downgradient of the fields also did not indicate any changes related to sludge. Florida Department of Environmental Regulation primary and secondary drinking-water regulations wer exceeded at the Rockdale maximum-application field by mercury (9.5 ug/L (micrograms per liter)), and the Perrine marl maximum-application field by manganese (60 ug/L) and lead (85 ug/L), and at the

  16. Hanford facility dangerous waste permit application, 325 hazardous waste treatment units. Revision 1

    SciTech Connect

    1997-07-01

    This report contains the Hanford Facility Dangerous Waste Permit Application for the 325 Hazardous Waste Treatment Units (325 HWTUs) which consist of the Shielded Analytical Laboratory, the 325 Building, and the 325 Collection/Loadout Station Tank. The 325 HWTUs receive, store, and treat dangerous waste generated by Hanford Facility programs. Routine dangerous and/or mixed waste treatment that will be conducted in the 325 HWTUs will include pH adjustment, ion exchange, carbon absorption, oxidation, reduction, waste concentration by evaporation, precipitation, filtration, solvent extraction, solids washing, phase separation, catalytic destruction, and solidification/stabilization.

  17. Comparison of methods for estimating ground-water recharge and base flow at a small watershed underlain by fractured bedrock in the Eastern United States

    USGS Publications Warehouse

    Risser, Dennis W.; Gburek, William J.; Folmar, Gordon J.

    2005-01-01

    This study by the U.S. Geological Survey (USGS), in cooperation with the Agricultural Research Service (ARS), U.S. Department of Agriculture, compared multiple methods for estimating ground-water recharge and base flow (as a proxy for recharge) at sites in east-central Pennsylvania underlain by fractured bedrock and representative of a humid-continental climate. This study was one of several within the USGS Ground-Water Resources Program designed to provide an improved understanding of methods for estimating recharge in the eastern United States. Recharge was estimated on a monthly and annual basis using four methods?(1) unsaturated-zone drainage collected in gravity lysimeters, (2) daily water balance, (3) water-table fluctuations in wells, and (4) equations of Rorabaugh. Base flow was estimated by streamflow-hydrograph separation using the computer programs PART and HYSEP. Estimates of recharge and base flow were compared for an 8-year period (1994-2001) coinciding with operation of the gravity lysimeters at an experimental recharge site (Masser Recharge Site) and a longer 34-year period (1968-2001), for which climate and streamflow data were available on a 2.8-square-mile watershed (WE-38 watershed). Estimates of mean-annual recharge at the Masser Recharge Site and WE-38 watershed for 1994-2001 ranged from 9.9 to 14.0 inches (24 to 33 percent of precipitation). Recharge, in inches, from the various methods was: unsaturated-zone drainage, 12.2; daily water balance, 12.3; Rorabaugh equations with PULSE, 10.2, or RORA, 14.0; and water-table fluctuations, 9.9. Mean-annual base flow from streamflow-hydrograph separation ranged from 9.0 to 11.6 inches (21-28 percent of precipitation). Base flow, in inches, from the various methods was: PART, 10.7; HYSEP Local Minimum, 9.0; HYSEP Sliding Interval, 11.5; and HYSEP Fixed Interval, 11.6. Estimating recharge from multiple methods is useful, but the inherent differences of the methods must be considered when comparing

  18. Influence of permafrost distribution on groundwater flow in the context of climate-driven permafrost thaw: example from Yukon Flats Basin, Alaska, United States

    USGS Publications Warehouse

    Walvoord, Michelle A.; Voss, Clifford I.; Wellman, Tristan P.

    2012-01-01

    Understanding the role of permafrost in controlling groundwater flow paths and fluxes is central in studies aimed at assessing potential climate change impacts on vegetation, species habitat, biogeochemical cycling, and biodiversity. Recent field studies in interior Alaska show evidence of hydrologic changes hypothesized to result from permafrost degradation. This study assesses the hydrologic control exerted by permafrost, elucidates modes of regional groundwater flow for various spatial permafrost patterns, and evaluates potential hydrologic consequences of permafrost degradation. The Yukon Flats Basin (YFB), a large (118,340 km2) subbasin within the Yukon River Basin, provides the basis for this investigation. Model simulations that represent an assumed permafrost thaw sequence reveal the following trends with decreasing permafrost coverage: (1) increased groundwater discharge to rivers, consistent with historical trends in base flow observations in the Yukon River Basin, (2) potential for increased overall groundwater flux, (3) increased spatial extent of groundwater discharge in lowlands, and (4) decreased proportion of suprapermafrost (shallow) groundwater contribution to total base flow. These trends directly affect the chemical composition and residence time of riverine exports, the state of groundwater-influenced lakes and wetlands, seasonal river-ice thickness, and stream temperatures. Presently, the YFB is coarsely mapped as spanning the continuous-discontinuous permafrost transition that model analysis shows to be a critical threshold; thus, the YFB may be on the verge of major hydrologic change should the current permafrost extent decrease. This possibility underscores the need for improved characterization of permafrost and other hydrogeologic information in the region via geophysical techniques, remote sensing, and ground-based observations.

  19. Groundwater quality in the Columbia Plateau, Snake River Plain, and Oahu basaltic-rock and basin-fill aquifers in the Northwestern United States and Hawaii, 1992-2010

    USGS Publications Warehouse

    Frans, Lonna M.; Rupert, Michael G.; Hunt, Charles D., Jr.; Skinner, Kenneth D.

    2012-01-01

    samples from all three study areas, but other pesticides were detected only in samples from Oahu, or only in samples from the Columbia Plateau and Snake River Plain. This is because some pesticides (such as atrazine) are broad-spectrum pesticides that are used on many crops in many different areas of the United States. Other pesticides (such as simazine, metribuzin, and metolachlor) are used on row crops (such as potatoes, barley, and alfalfa) grown in the Columbia Plateau and Snake River Plain, but not on pineapple or sugarcane grown in Oahu. Atrazine logistic-regression models indicate that areas with a high percentage of land in crops (such as potatoes or sugarcane), a low percentage of fallow land, and highly permeable soils with low amounts of organic matter are most likely to have atrazine detected in the groundwater. Areas where agricultural activities were absent had much lower probabilities of atrazine being detected. The Snake River Plain had a much higher probability of atrazine detections, with more than 50 percent of the land area having greater than a 50 percent probability of atrazine contamination. Oahu had a much lower probability of atrazine contamination, with only 24 percent of the land area having greater than a 50 percent probability of atrazine contamination. Oahu and the Columbia Plateau had some of the highest percentages of soil fumigant detections in groundwater in the United States. Soil fumigants are volatile organic compounds (VOCs) used as pesticides, which are applied to soils to reduce populations of plant parasitic nematodes (harmful rootworms), weeds, fungal pathogens, and other soil-borne microorganisms. They are used in Oahu and the Columbia Plateau on crops such as pineapple and potatoes. All three areas (Columbia Plateau, Snake River Plain, and Oahu) had fumigant concentrations exceeding human-health benchmarks for drinking water.

  20. Groundwater quality in the North San Francisco Bay groundwater basins, California

    USGS Publications Warehouse

    Kulongoski, Justin T.; Belitz, Kenneth

    2010-01-01

    Groundwater provides more than 40 percent of California's drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State's groundwater quality and increases public access to groundwater-quality information. The basins north of San Francisco constitute one of the study units being evaluated.

  1. Use of Interface Treatment to Reduce Emissions from Residuals in Lower Permeability Zones to Groundwater flowing Through More Permeable Zones (Invited)

    NASA Astrophysics Data System (ADS)

    Johnson, P.; Cavanagh, B.; Clifton, L.; Daniels, E.; Dahlen, P.

    2013-12-01

    Many soil and groundwater remediation technologies rely on fluid flow for contaminant extraction or reactant delivery (e.g., soil vapor extraction, pump and treat, in situ chemical oxidation, air sparging, enhanced bioremediation). Given that most unconsolidated and consolidated settings have permeability contrasts, the outcome is often preferential treatment of more permeable zones and ineffective treatment of the lower permeability zones. When this happens, post-treatment contaminant emissions from low permeability zone residuals can cause unacceptable long-term impacts to groundwater in the transmissive zones. As complete remediation of the impacted lower permeability zones may not be practicable with conventional technologies, one might explore options that lead to reduction of the contaminant emissions to acceptable levels, rather than full remediation of the lower permeability layers. This could be accomplished either by creating a sustained emission reaction/attenuation zone at the high-low permeability interface, or by creating a clean soil zone extending sufficiently far into the lower permeability layer to cause the necessary reduction in contaminant concentration gradient and diffusive emission. These options are explored in proof-of-concept laboratory-scale physical model experiments. The physical models are prepared with two layers of contrasting permeability and either dissolved matrix storage or nonaqueous phase liquid (NAPL) in the lower permeability layer. A dissolved oxidant is then delivered to the interface via flow across the higher permeability layer and changes in contaminant emissions from the low permeability zone are monitored before, during, and after oxidant delivery. The use of three oxidants (dissolved oxygen, hydrogen peroxide and sodium persulfate) for treatment of emissions from petroleum hydrocarbon residuals is examined.

  2. Proposed plan for remedial action for the Groundwater Operable Unit at the Chemical Plant Area of the Weldon Spring Site, Weldon Spring, Missouri

    SciTech Connect

    1999-08-10

    This Proposed Plan addresses the remediation of groundwater contamination at the chemical plant area of the Weldon Spring site in Weldon Spring, Missouri. The site is located approximately 48 km (30 mi) west of St. Louis in St. Charles County . Remedial activities at the site will be conducted in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). The U.S. Department of Energy (DOE), in conjunction with the U.S. Department of the Army (DA), conducted a joint remedial investigation/feasibility study (RI/FS) to allow for a comprehensive evaluation of groundwater conditions at the Weldon Spring chemical plant area and the Weldon Spring ordnance works area, which is an Army site adjacent to the chemical plant area. Consistent with DOE policy, National Environmental Policy Act (NEPA) values have been incorporated into the CERCLA process. That is, the analysis conducted and presented in the RVFS reports included an evaluation of environmental impacts that is comparable to that performed under NEPA. This Proposed Plan summarizes information about chemical plant area groundwater that is presented in the following documents: (1) The Remedial Investigation (RI), which presents information on the nature and extent of contamination; (2) The Baseline Risk Assessment (BRA), which evaluates impacts to human health and the environment that could occur if no cleanup action of the groundwater were taken (DOE and DA 1997a); and (3) The Feasibility Study (FS) and the Supplemental FS, which develop and evaluate remedial action alternatives for groundwater remediation.

  3. Groundwater exposed

    NASA Astrophysics Data System (ADS)

    2016-02-01

    Groundwater flow meddles with hydrological, environmental and geological processes. As water scarcity issues mount for people living above ground, the vast stores of freshwater in the subsurface require research attention.

  4. Using Cl/Br ratios and other indicators to assess potential impacts on groundwater quality from septic systems: A review and examples from principal aquifers in the United States

    USGS Publications Warehouse

    Katz, B.G.; Eberts, S.M.; Kauffman, L.J.

    2011-01-01

    A detailed review was made of chemical indicators used to identify impacts from septic tanks on groundwater quality. Potential impacts from septic tank leachate on groundwater quality were assessed using the mass ratio of chloride-bromide (Cl/Br), concentrations of selected chemical constituents, and ancillary information (land use, census data, well depth, soil characteristics) for wells in principal aquifers of the United States. Chemical data were evaluated from 1848 domestic wells in 19 aquifers, 121 public-supply wells in 6 aquifers, and associated monitoring wells in four aquifers and their overlying hydrogeologic units. Based on previously reported Cl/Br ratios, statistical comparisons between targeted wells (where Cl/Br ratios range from 400 to 1100 and Cl concentrations range from 20 to 100 mg/L) and non-targeted wells indicated that shallow targeted monitoring and domestic wells (0.5. mg/L) shallow groundwater from target domestic wells, relative to non-target wells (1.5. mg/L), corresponded to significantly higher potassium, boron, chloride, dissolved organic carbon, and sulfate concentrations, which may also indicate the influence of septic-tank effluent. Impacts on groundwater quality from septic systems were most evident for the Eastern Glacial Deposits aquifer and the Northern High Plains aquifer that were associated with the number of housing units using septic tanks, high permeability of overlying sediments, mostly oxic conditions, and shallow wells. Overall, little or no influence from septic systems were found for water samples from the deeper public-supply wells.The Cl/Br ratio is a useful first-level screening tool for assessing possible septic tank influence in water from shallow wells (<20 m) with the range of 400-1100. The use of this ratio would be enhanced with information on other chloride sources, temporal variability of chloride and bromide concentrations in shallow groundwater, knowledge of septic-system age and maintenance, and the

  5. Using Cl/Br ratios and other indicators to assess potential impacts on groundwater quality from septic systems: A review and examples from principal aquifers in the United States

    NASA Astrophysics Data System (ADS)

    Katz, Brian G.; Eberts, Sandra M.; Kauffman, Leon J.

    2011-02-01

    SummaryA detailed review was made of chemical indicators used to identify impacts from septic tanks on groundwater quality. Potential impacts from septic tank leachate on groundwater quality were assessed using the mass ratio of chloride-bromide (Cl/Br), concentrations of selected chemical constituents, and ancillary information (land use, census data, well depth, soil characteristics) for wells in principal aquifers of the United States. Chemical data were evaluated from 1848 domestic wells in 19 aquifers, 121 public-supply wells in 6 aquifers, and associated monitoring wells in four aquifers and their overlying hydrogeologic units. Based on previously reported Cl/Br ratios, statistical comparisons between targeted wells (where Cl/Br ratios range from 400 to 1100 and Cl concentrations range from 20 to 100 mg/L) and non-targeted wells indicated that shallow targeted monitoring and domestic wells (<20 m depth below land surface) had a significantly ( p < 0.05) higher median percentage of houses with septic tanks (1990 census data) than non-targeted wells. Higher ( p = 0.08) median nitrate-N concentration (3.1 mg/L) in oxic (dissolved oxygen concentrations >0.5 mg/L) shallow groundwater from target domestic wells, relative to non-target wells (1.5 mg/L), corresponded to significantly higher potassium, boron, chloride, dissolved organic carbon, and sulfate concentrations, which may also indicate the influence of septic-tank effluent. Impacts on groundwater quality from septic systems were most evident for the Eastern Glacial Deposits aquifer and the Northern High Plains aquifer that were associated with the number of housing units using septic tanks, high permeability of overlying sediments, mostly oxic conditions, and shallow wells. Overall, little or no influence from septic systems were found for water samples from the deeper public-supply wells. The Cl/Br ratio is a useful first-level screening tool for assessing possible septic tank influence in water from

  6. Monitoring Plan for RCRA Groundwater Assessment at the 216-U-12 Crib

    SciTech Connect

    Williams, Bruce A.; Chou, Charissa J.

    2005-09-20

    This document contains a revised and updated monitoring plan for RCRA interim status groundwater assessment, site hydrogeology, and a conceptual model of the RCRA treatment, storage, and disposal unit. Monitoring under interim status is expected to continue until the 216-U-12 crib is incorporated as a chapter into the Hanford Facility RCRA Permit or administratively closed as proposed to EPA and Ecology.

  7. Phase I Hydrologic Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada Test Site, Nye County, Nevada, Rev. No.: 0

    SciTech Connect

    John McCord

    2006-06-01

    The U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office (NNSA/NSO) initiated the Underground Test Area (UGTA) Project to assess and evaluate the effects of the underground nuclear weapons tests on groundwater beneath the Nevada Test Site (NTS) and vicinity. The framework for this evaluation is provided in Appendix VI, Revision No. 1 (December 7, 2000) of the Federal Facility Agreement and Consent Order (FFACO, 1996). Section 3.0 of Appendix VI ''Corrective Action Strategy'' of the FFACO describes the process that will be used to complete corrective actions specifically for the UGTA Project. The objective of the UGTA corrective action strategy is to define contaminant boundaries for each UGTA corrective action unit (CAU) where groundwater may have become contaminated from the underground nuclear weapons tests. The contaminant boundaries are determined based on modeling of groundwater flow and contaminant transport. A summary of the FFACO corrective action process and the UGTA corrective action strategy is provided in Section 1.5. The FFACO (1996) corrective action process for the Yucca Flat/Climax Mine CAU 97 was initiated with the Corrective Action Investigation Plan (CAIP) (DOE/NV, 2000a). The CAIP included a review of existing data on the CAU and proposed a set of data collection activities to collect additional characterization data. These recommendations were based on a value of information analysis (VOIA) (IT, 1999), which evaluated the value of different possible data collection activities, with respect to reduction in uncertainty of the contaminant boundary, through simplified transport modeling. The Yucca Flat/Climax Mine CAIP identifies a three-step model development process to evaluate the impact of underground nuclear testing on groundwater to determine a contaminant boundary (DOE/NV, 2000a). The three steps are as follows: (1) Data compilation and analysis that provides the necessary modeling data that is

  8. A brief history and some current dimensions of adolescent treatment in the United States.

    PubMed

    Godley, Mark D; White, William L

    2005-01-01

    Resources for the treatment of adolescent substance use disorders have increased over the past century in tandem with the increased visibility and cultural alarm regarding adolescent substance-related problems. The United States now has a multi-branched and growing system of adolescent treatment services that spans public and private sectors and offers services in both specialty and non-specialty service settings. Most adolescents are entering treatment due to alcohol and/or cannabis-related problems (and, to a lesser degree, other illicit drugs), but present with a wide array of co-occurring problems and obstacles to recovery. Multiple levels of specialized care are available but most adolescents being treated via outpatient counseling. The number and methodological rigor of adolescent treatment outcome studies have increased dramatically in recent years. The findings of these studies suggest the need for earlier systems of problem identification and intervention, a model of sustained recovery support for adolescents presenting with high problem severity and complexity, and sustained interventions with the adolescent's post-treatment family and social environment. In the opening decade of the twenty-first century, the treatment of adolescent substance use disorders is itself maturing into a professionalized and science-guided service arena. PMID:15789876

  9. Contain contaminated groundwater

    SciTech Connect

    Mutch, R.D. Jr.; Caputi, J.R.; Ash, R.E. IV

    1997-05-01

    Despite recent progress in innovative treatment technologies, many problems with contaminated groundwater still require the use of barrier walls, typically in combination with extraction and treatment systems. New technologies for subsurface barrier walls, mostly based on geomembranes, advancements in self-hardening slurries and permeation grouts with materials such as colloidal silica gel and montan wax emulsions, are being developed at an unprecedented pace. The paper discusses deep soil mixing, jet grouting, slurry trenches, and permeation grouting.

  10. Independent dose per monitor unit review of eight U.S.A. proton treatment facilities

    PubMed Central

    Moyers, M. F.; Ibbott, G. S.; Grant, R. L.; Summers, P. A.; Followill, D. S.

    2014-01-01

    Purpose: Compare the dose per monitor unit at different proton treatment facilities using three different dosimetry methods. Methods: Measurements of dose per monitor unit were performed by a single group at eight facilities using 11 test beams and up to six different clinical portal treatment sites. These measurements were compared to the facility reported dose per monitor unit values. Results: Agreement between the measured and reported doses was similar using any of the three dosimetry methods. Use of the ICRU 59 ND,w based method gave results approximately 3% higher than both the ICRU 59 NX and ICRU 78 (TRS-398) ND,w based methods. Conclusions: Any single dosimetry method could be used for multi-institution trials with similar conformity between facilities. A multi-institutional trial could support facilities using both the ICRU 59 NX based and ICRU 78 (TRS-398) ND,w based methods but use of the ICRU 59 ND,w based method should not be allowed simultaneously with the other two until the difference is resolved. PMID:24387521

  11. Independent dose per monitor unit review of eight U.S.A. proton treatment facilities

    SciTech Connect

    Moyers, M. F.; Ibbott, G. S.; Grant, R. L.; Summers, P. A.; Followill, D. S.

    2014-01-15

    Purpose: Compare the dose per monitor unit at different proton treatment facilities using three different dosimetry methods. Methods: Measurements of dose per monitor unit were performed by a single group at eight facilities using 11 test beams and up to six different clinical portal treatment sites. These measurements were compared to the facility reported dose per monitor unit values. Results: Agreement between the measured and reported doses was similar using any of the three dosimetry methods. Use of the ICRU 59 N{sub D,w} based method gave results approximately 3% higher than both the ICRU 59 N{sub X} and ICRU 78 (TRS-398) N{sub D,w} based methods. Conclusions: Any single dosimetry method could be used for multi-institution trials with similar conformity between facilities. A multi-institutional trial could support facilities using both the ICRU 59 N{sub X} based and ICRU 78 (TRS-398) N{sub D,w} based methods but use of the ICRU 59 N{sub D,w} based method should not be allowed simultaneously with the other two until the difference is resolved.

  12. Mining's impact on groundwater assessed

    NASA Astrophysics Data System (ADS)

    Detailed studies have indicated that groundwater is contaminated in the immediate vicinity of many mines in the eastern United States. However, no underground mines and very few refuse disposal areas have monitoring systems that can provide adequate warning of impending threats to groundwater quality.This was one of the conclusions of a 3-year study by Geraghty & Miller, Inc., a firm of consulting groundwater geologists and hydrologists based in Syosset, New York. The study focused on mines east of the 100th meridian. These mines will produce an estimated 1.1 billion tons of coal and 200 million tons of waste by 1985.

  13. The effects of artificial recharge on groundwater levels and water quality in the west hydrogeologic unit of the Warren subbasin, San Bernardino County, California

    USGS Publications Warehouse

    Stamos, Christina L.; Martin, Peter; Everett, Rhett; Izbicki, John A.

    2013-01-01

    Between the late 1940s and 1994, groundwater levels in the Warren subbasin, California, declined by as much as 300 feet because pumping exceeded sparse natural recharge. In response, the local water district, Hi-Desert Water District, implemented an artificial-recharge program in early 1995 using imported water from the California State Water Project. Subsequently, the water table rose by as much as 250 feet; however, a study done by the U.S. Geological Survey found that the rising water table entrained high-nitrate septic effluent, which caused nitrate (as nitrogen) concentrations in some wells to increase to more than the U.S. Environmental Protection Agency maximum contaminant level of 10 milligrams per liter.. A new artificial-recharge site (site 3) was constructed in 2006 and this study, which started in 2004, was done to address concerns about the possible migration of nitrates in the unsaturated zone. The objectives of this study were to: (1) characterize the hydraulic, chemical, and microbiological properties of the unsaturated zone; (2) monitor changes in water levels and water quality in response to the artificial-recharge program at site 3; (3) determine if nitrates from septic effluent infiltrated through the unsaturated zone to the water table; (4) determine the potential for nitrates within the unsaturated zone to mobilize and contaminate the groundwater as the water table rises in response to artificial recharge; and (5) determine the presence and amount of dissolved organic carbon because of its potential to react with disinfection byproducts during the treatment of water for public use. Two monitoring sites were installed and instrumented with heat-dissipation probes, advanced tensiometers, suction-cup lysimeters, and wells so that the arrival and effects of recharging water from the State Water Project through the 250 to 425 foot-thick unsaturated zone and groundwater system could be closely observed. Monitoring site YVUZ-1 was located between two

  14. Contribution of siloxanes to COD loading at wastewater treatment plants: phase transfer, removal, and fate at different treatment units.

    PubMed

    Surita, Sharon C; Tansel, Berrin

    2015-03-01

    Cyclic volatile methylsiloxanes (cVMSs) are entering to waste stream in increasing quantities due to their increasing use in personal care products (i.e., shampoos, creams). The cVMSs have high vapor pressures and low solubilities and are mostly transferred into the gaseous phase via volatilization; however, some are sorbed onto biosolids. The purpose of this study was to track and estimate the phase transfer (water, solids, gas), fate, and contribution to COD loading of selected siloxanes (D4, D5 and D6) which are the most commonly found cVMSs in the wastewater systems. Removal efficiencies of the wastewater treatment units were evaluated based on the partitioning characteristics of the cVMSs in gas, liquid, and biosolids phases. The contributions of the siloxanes present in the influent and effluent were estimated in terms of COD levels based on the theoretical oxygen demand (ThOD) of the siloxanes. Siloxanes constitute approximately 39 and 0.001mgL(-1) of the COD in the influents and effluent. Oxidation systems showed higher removal efficiencies based COD loading in comparison to the removal efficiencies achieved aeration tanks and filtration systems. Treatment systems effectively remove the siloxanes from the aqueous phase with over 94% efficiency. About 50% of the siloxanes entering to the wastewater treatment plant accumulate in biosolids. PMID:25528947

  15. Mobile stroke units bring treatment to patients, potentially improving long-term outcomes.

    PubMed

    2016-01-01

    At least three U.S. medical centers are evaluating the benefits of deploying specially equipped mobile stroke units to respond to emergency calls for patients with suspected strokes. Most of these units contain CT scanners, lab facilities, and other functionality capable of determining whether a patient would benefit from clot-busting therapy. Such drugs can then be administered to appropriate patients before a patient even arrives in the ED. Early findings from the approach show that care can be accelerated, potentially improving stroke outcomes and reducing longer-term costs. In Houston, a mobile stroke unit dispatches along with EMS when a call involves a potential stroke victim. If the mobile stroke unit team determines that a patient is a candidate for clot-busting therapy, clinicians can administer the therapy, accelerating potentially brain-saving care. In a nine-week period, researchers reported that they treated about two patients per week with clot-busting drugs, 40% of whom received treatment within the first hour of onset. Further, none of the patients who received the drugs experienced intracerebral hemorrhage, and half of them recovered fully from their strokes within 90 days. PMID:26731930

  16. Reasons for changes in the value of unit pressure of compression products supporting external treatment

    NASA Astrophysics Data System (ADS)

    Kowalski, K.; Ilska, A.; Kłonowska, M.

    2016-07-01

    The paper presents the basics of modelling compression products with intended values of unit pressure for body circumferences with fixed and variable radius of curvature. The derived relationships referring to the dimensions of the fabric's circumferences in a relaxed state of the product were based on Laplace law, local values of the radius of curvature, and the characteristics of stretching and relaxing (deformation) of the knitted fabric, described by experimental relation for the stress and relaxation phase for the 6th hysteresis loop, taking into account confidence intervals. The article indicates the possibilities of using 3D scanning techniques of the human body to identify the radius of curvature of various circumference of the human silhouette, for which the intended value of the unit pressure is designed, and quantitative changes in the body deformation due to compression. Classic method of modelling and design of compression products, based on a cylindrical model of the human body does not provide in each case the intended value of unit pressure, according to specific normative requirements, because it neglects the effect of different values of the radius of curvature of the body circumference and the properties of the viscoelastic knitted fabrics. The model and experimental research allowed for a quantitative and qualitative assessment of the reasons for the changes in the value of unit pressure of compression products supporting the process of external treatment.

  17. Hydraulic design to optimize the treatment capacity of Multi-Stage Filtration units

    NASA Astrophysics Data System (ADS)

    Mushila, C. N.; Ochieng, G. M.; Otieno, F. A. O.; Shitote, S. M.; Sitters, C. W.

    2016-04-01

    Multi-Stage Filtration (MSF) can provide a robust treatment alternative for surface water sources of variable water quality in rural communities at low operation and maintenance costs. MSF is a combination of Slow Sand Filters (SSFs) and Pre-treatment systems. The general objective of this research was to optimize the treatment capacity of MSF. A pilot plant study was undertaken to meet this objective. The pilot plant was monitored for a continuous 98 days from commissioning till the end of the project. Three main stages of MSF namely: The Dynamic Gravel Filter (DGF), Horizontal-flow Roughing Filter (HRF) and SSF were identified, designed and built. The response of the respective MSF units in removal of selected parameters guiding drinking water quality such as microbiological (Faecal and Total coliform), Suspended Solids, Turbidity, PH, Temperature, Iron and Manganese was investigated. The benchmark was the Kenya Bureau (KEBS) and World Health Organization (WHO) Standards for drinking water quality. With respect to microbiological raw water quality improvement, MSF units achieved on average 98% Faecal and 96% Total coliform removal. Results obtained indicate that implementation of MSF in rural communities has the potential to increase access to portable water to the rural populace with a probable consequent decrease in waterborne diseases. With a reduced down time due to illness, more time would be spent in undertaking other economic activities.

  18. Engineered In-Situ Precipitation of Technetium and Uranium in Groundwater at the Savannah River Site: Treatment Targeting Long-Term Stability (Invited)

    NASA Astrophysics Data System (ADS)

    Gillow, J. B.; Lutes, C. C.; Frizzell, A.; Clark, B.; Horst, J.

    2009-12-01

    The U.S. Department of Energy (DOE) Savannah River Site (SRS) is a former nuclear weapons facility that is undergoing clean-up of groundwater and soil contamination. Alternatives to conventional pump-and-treat are being evaluated through DOE’s Advanced Remediation Technologies (ART) program as part of the EM-22 Groundwater and Soil Remediation program. A pilot project is underway to evaluate an emerging approach to remediation through the in-situ precipitation of insoluble forms of technetium and uranium. The demonstration involves the injection of organic carbon into the aquifer to stimulate biogeochemical processes leading to the transformation of soluble radionuclides to insoluble forms. However, once carbon addition is ceased and geochemical conditions return to oxidizing, the insoluble radionuclides may re-dissolve. The pilot project will target long term stability by enhancing the creation of reduced mineral forms in and around the precipitated radionuclides to act as both a redox buffer for oxidizing groundwater and as a sorptive medium for any dissolved uranium and technetium. Successful treatment with respect to in situ radionuclide precipitation extends beyond numeric cleanup goals and invokes a standard of care that considers not only short-term solubility achieved during active remediation, but the range of factors that might erode/compromise the stability of the precipitated solids over the long-term. Long-term stability may be achieved by incorporating the targeted radionuclide in a matrix of other precipitates formed through the treatment process. In the short term, this can include the precipitates of other more abundant metals (e.g., iron) that can preferentially scavenge oxygen. Longer term, this is expected to transition to passivation within a matrix of more stable mineral phases, such that rates of rebound dissolution are sufficiently suppressed to maintain dissolved concentrations below remedial targets. The in situ reactive zone (IRZ

  19. Women-Centered Drug Treatment Services and Need in the United States, 2002–2009

    PubMed Central

    Terplan, Mishka; Longinaker, Nyaradzo; Appel, Lindsay

    2016-01-01

    Objectives We examined options and need for women-centered substance use disorder treatment in the United States between 2002 and 2009. Methods We obtained characteristics of facilities from the National Survey of Substance Abuse Treatment Services and treatment need data from the National Survey on Drug Use and Health. We also examined differences in provision of women-centered programs by urbanization level in data from the National Center for Health Statistics 2006 Rural-Urban County Continuum. Results Of the 13000 facilities surveyed annually, the proportion offering women-centered services declined from 43% in 2002 to 40% in 2009 (P<.001). Urban location, state population size, and Medicaid payment predicted provision of such services as trauma-related and domestic violence counseling, child care, and housing assistance (all, P<.001). Prevalence of women with unmet need ranged from 81% to 95% across states. Conclusions Change in availability of women-centered drug treatment services was minimal from 2002 to 2009, even though need for treatment was high in all states. PMID:26378825

  20. REMOVAL OF DBCP FROM GROUNDWATER-VOLUME 1. POE/POU TREATMENT DEVICES: INSTITUTIONAL AND JURISDICTIONAL FACTORS

    EPA Science Inventory

    The results obtained from evaluating ten GAG POE (point-of-entry) devices show that while these GAG units generally function very satisfactorily, their performance can change markedly over short periods of time. These units require conscientious, periodic monitoring. The monitori...

  1. Development and use of mobile containment units for the evaluation and treatment of potential Ebola virus disease patients in a United States hospital.

    PubMed

    Sugalski, Gregory; Murano, Tiffany; Fox, Adam; Rosania, Anthony

    2015-05-01

    Ebola virus disease (EVD) has been the subject of recent attention due to the current outbreak in West Africa, as well as the appearance of a number of cases within the United States. The presence of EVD patients in the United States required health care systems to prepare for the identification and management of both patients under investigation and patients with confirmed EVD infection. This article discusses the development and use of a mobile containment unit in an extended treatment area as a novel approach to isolation and screening of potential EVD patients. PMID:25900204

  2. Annual report of 1990 groundwater, monitoring data for treatment, storage, or disposal facilities at the Y-12 plant

    SciTech Connect

    Early, T.O.; Switek, J. )

    1991-02-01

    The purpose of this document is to provide a summary and interpretation of hydrostatic head measurements obtained from wells surrounding the Kerr Hollow Quarry and Chestnut Ridge Sediment Disposal Basin sites at the US Department of Energy Y-12 Plant in Oak Ridge, Tennessee. Water level observations are presented using hydrographs and water table elevation maps based on data obtained during calendar year 1990. Generalized, preliminary interpretation of results are presented. The two sites covered by the this report have interim status under the provisions of the Resource Conservation and Recovery Act (RCRA). A subset of the wells at each are used for groundwater monitoring purposes under the requirements of RCRA. A discussion of the upgradient and downgradient directions for each of the sites is included. 18 refs., 14 figs.

  3. Summary report on the demonstration of the Duratek process for treatment of mixed-waste contaminated groundwater

    SciTech Connect

    Singh, S.P.N.; Lomenick, T.F.

    1992-04-01

    This report presents the results of the demonstration of the Duratek process for removal of radioactive and hazardous waste compounds from mixed-waste contaminated groundwaters found at the Department of Energy (DOE) sites managed by Martin Marietta Energy Systems (Energy Systems). The process uses Duratek proprietary Durasil{reg_sign} ion-exchange media to remove the above contaminants from the water to produce treated water that can meet current and proposed drinking water quality standards with regard to the above contaminants. The demonstration showed that the process is simple, compact, versatile, and rugged and requires only minimal operator attention. It is thus recommended that this process be considered for remediating the mixed-waste contaminated waters found at the Energy Systems-managed DOE sites.

  4. Summary report on the demonstration of the Duratek process for treatment of mixed-waste contaminated groundwater

    SciTech Connect

    Singh, S.P.N.; Lomenick, T.F.

    1992-04-01

    This report presents the results of the demonstration of the Duratek process for removal of radioactive and hazardous waste compounds from mixed-waste contaminated groundwaters found at the Department of Energy (DOE) sites managed by Martin Marietta Energy Systems (Energy Systems). The process uses Duratek proprietary Durasil{reg sign} ion-exchange media to remove the above contaminants from the water to produce treated water that can meet current and proposed drinking water quality standards with regard to the above contaminants. The demonstration showed that the process is simple, compact, versatile, and rugged and requires only minimal operator attention. It is thus recommended that this process be considered for remediating the mixed-waste contaminated waters found at the Energy Systems-managed DOE sites.

  5. Resource Conservation and Recovery Act (RCRA) closure sumamry for the Uranium Treatment Unit

    SciTech Connect

    1996-05-01

    This closure summary has been prepared for the Uranium Treatment Unit (UTU) located at the Y-12 Plant in Oak Ridge, Tennessee. The actions required to achieve closure of the UTU area are outlined in the Closure Plan, submitted to and approved by the Tennessee Department of Environmental and Conservation staff, respectively. The UTU was used to store and treat waste materials that are regulated by the Resource Conservation and Recovery Act. This closure summary details all steps that were performed to close the UTU in accordance with the approved plan.

  6. Renal cell cancer: a shift in approaches for treatment of advanced disease in the United States.

    PubMed

    Banegas, Matthew P; Harlan, Linda C; Mann, Bhupinder; Yabroff, K Robin

    2014-09-01

    Several new agents have become available to treat renal cell cancer (RCC) in recent years, although evidence on their dissemination is limited. This study examined recent trends in RCC treatment in US community practices. Data from the population-based National Cancer Institute's Patterns of Care studies were used to evaluate treatment of patients with RCC newly diagnosed in 2004 and 2009 (N=2357). Descriptive statistics and logistic and Cox proportional hazards regression analyses were used to assess treatment patterns and the associations among demographic, clinical, and hospital characteristics, with receipt of systemic therapy and time-to-systemic treatment. Between 2004 and 2009, systemic therapy use increased among patients with stage III and IV RCC, from 3.8% to 15.7% and 35.2% to 57.4%, respectively. Among patients with stage IV disease, the most commonly used therapies changed from interleukin-2 (16.3%) and interferon-alfa (16.6%) in 2004 to sunitinib (39.2%) and temsirolimus (15.2%) in 2009. Further, notable decreases were seen in the use of surgery and time-to-systemic treatment for patients with stage IV disease. Patients who were older, living in areas with lower educational attainment, and diagnosed in 2004 were significantly less likely to receive systemic therapy and had longer time-to-systemic treatment (P<.05). The findings indicate that over the past decade, treatment for RCC in the United States has evolved toward increased use of systemic therapy. As the diffusion of new therapies continues, it will be imperative to understand how variation in care for RCC will impact health outcomes and costs of care. PMID:25190695

  7. A case of a chlorine inhalation injury in an Ebola treatment unit.

    PubMed

    Carpenter, Adrian; Cox, A T; Marion, D; Phillips, A; Ewington, I

    2016-06-01

    We present a 26-year-old male British military nurse, deployed to Sierra Leone to treat patients with Ebola virus disease at the military-run Kerry Town Ebola Treatment Unit. Following exposure to chlorine gas during routine maintenance procedures, the patient had an episode of respiratory distress and briefly lost consciousness after exiting the facility. Diagnoses of reactive airways disease, secondary to the chlorine exposure and a hypocapnic syncopal episode were made. The patient was resuscitated with minimal intervention and complete recovery occurred in less than 1 week. This case highlights the issues of using high-strength chlorine solution to disinfect the red zone. Although this patient had a good outcome, this was fortunate. Ensuring Ebola treatment centres are optimally designed and that appropriate management systems are formulated with extraction scenarios rehearsed are important to mitigate the chlorine-associated risk. PMID:26472120

  8. Global Groundwater related Risk Indicators: quantifying groundwater stress and groundwater table decline (1990-2010) at global scale

    NASA Astrophysics Data System (ADS)

    Faneca Sanchez, Marta; Sutanudjaja, Edwin; Kuijper, Marijn; Bierkens, Marc

    2016-04-01

    Groundwater is an invisible but indispensable resource for the economic development of many countries. Due to the need for this resource, in many cases it is exploited under severe pressure and the exploitation can become not sustainable. The non-sustainable exploitation of water is a well-known problem on both regional and global scales. However, most currently-available assessments on water stress still mostly focus on surface water and on water balances. In this work, we presented two global maps of groundwater risk indicators: an updated version of the groundwater stress (Gleeson et al., 2011, DOI: 10.1038/nature11295) and an indicator on groundwater table decline for the period 1990-2010. To calculate both indicators, we used the updated PCR-GLOBWB model output at 5 arcmin resolution (about 10 km at the equator), that is extended with an offline coupling to a global groundwater MODFLOW model. PCR-GLOBWB simulates daily river discharge and groundwater recharge, as well as surface water and groundwater abstraction rates. The latter are estimated internally within the model based on the simulation of their availabilities and water demands for irrigation and other sectors. The daily output of PCR-GLOBWB would then be aggregated to the monthly resolution and used to force the MODFLOW groundwater model resolving spatio-temporal groundwater table dynamics, incorporating the simulated groundwater abstraction of PCR-GLOBWB. Using the PCR-GLOBWB and MODFLOW simulation results from the period 1990-2010, we then quantified groundwater stress and assessed the groundwater table decline. Results are presented on four different spatial scales: 5 arcmin pixel, drainage/sub-catchment unit, state level, and major aquifer unit. The maps clearly show where groundwater is under stress, where there is a trend in the drop of the groundwater table, the slope of the drop and the significance of it.

  9. Land Application of Treated Sewage Sludge in the United States: Regulatory Considerations for Risk Reduction and Determining Treatment Process Equivalency

    EPA Science Inventory

    In the United States, municipal wastewater includes discharges from households, commercial businesses and various industries. Microorganisms associated with these wastes can be concentrated in the solids (sludge) which are removed during treatment operations. Beneficial reuse a...

  10. Assessing groundwater policy with coupled economic-groundwater hydrologic modeling

    NASA Astrophysics Data System (ADS)

    Mulligan, Kevin B.; Brown, Casey; Yang, Yi-Chen E.; Ahlfeld, David P.

    2014-03-01

    This study explores groundwater management policies and the effect of modeling assumptions on the projected performance of those policies. The study compares an optimal economic allocation for groundwater use subject to streamflow constraints, achieved by a central planner with perfect foresight, with a uniform tax on groundwater use and a uniform quota on groundwater use. The policies are compared with two modeling approaches, the Optimal Control Model (OCM) and the Multi-Agent System Simulation (MASS). The economic decision models are coupled with a physically based representation of the aquifer using a calibrated MODFLOW groundwater model. The results indicate that uniformly applied policies perform poorly when simulated with more realistic, heterogeneous, myopic, and self-interested agents. In particular, the effects of the physical heterogeneity of the basin and the agents undercut the perceived benefits of policy instruments assessed with simple, single-cell groundwater modeling. This study demonstrates the results of coupling realistic hydrogeology and human behavior models to assess groundwater management policies. The Republican River Basin, which overlies a portion of the Ogallala aquifer in the High Plains of the United States, is used as a case study for this analysis.

  11. Cone Beam Computed Tomography Image Guidance System for a Dedicated Intracranial Radiosurgery Treatment Unit

    SciTech Connect

    Ruschin, Mark; Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario ; Komljenovic, Philip T.; Ansell, Steve; Menard, Cynthia; Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario ; Bootsma, Gregory; Cho, Young-Bin; Chung, Caroline; Jaffray, David; Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario

    2013-01-01

    Purpose: Image guidance has improved the precision of fractionated radiation treatment delivery on linear accelerators. Precise radiation delivery is particularly critical when high doses are delivered to complex shapes with steep dose gradients near critical structures, as is the case for intracranial radiosurgery. To reduce potential geometric uncertainties, a cone beam computed tomography (CT) image guidance system was developed in-house to generate high-resolution images of the head at the time of treatment, using a dedicated radiosurgery unit. The performance and initial clinical use of this imaging system are described. Methods and Materials: A kilovoltage cone beam CT system was integrated with a Leksell Gamma Knife Perfexion radiosurgery unit. The X-ray tube and flat-panel detector are mounted on a translational arm, which is parked above the treatment unit when not in use. Upon descent, a rotational axis provides 210 Degree-Sign of rotation for cone beam CT scans. Mechanical integrity of the system was evaluated over a 6-month period. Subsequent clinical commissioning included end-to-end testing of targeting performance and subjective image quality performance in phantoms. The system has been used to image 2 patients, 1 of whom received single-fraction radiosurgery and 1 who received 3 fractions, using a relocatable head frame. Results: Images of phantoms demonstrated soft tissue contrast visibility and submillimeter spatial resolution. A contrast difference of 35 HU was easily detected at a calibration dose of 1.2 cGy (center of head phantom). The shape of the mechanical flex vs scan angle was highly reproducible and exhibited <0.2 mm peak-to-peak variation. With a 0.5-mm voxel pitch, the maximum targeting error was 0.4 mm. Images of 2 patients were analyzed offline and submillimeter agreement was confirmed with conventional frame. Conclusions: A cone beam CT image guidance system was successfully adapted to a radiosurgery unit. The system is capable of

  12. Commissioning a 50-100 kV X-ray unit for skin cancer treatment.

    PubMed

    Sheu, Ren-Dih; Powers, Allison; Lo, Yeh-Chi

    2015-01-01

    This study provides the authors' experience along with dosimetric data from the commissioning of two Sensus SRT-100 50-100 kV X-ray units. Data collected during the commissioning process included: a) HVL, b) output (dose rate), c) applicator cone factors, and d) percentage depth dose. A Farmer-type chamber (PTW-N23333), and a thin-window parallel plate ion chamber (PTW-N23342) were used for dose rate measurements and dose profiles were measured with EBT3 GafChromic film. The average HVL values for 50, 70, and 100 kV of the two treatment units were found to be 0.52, 1.15, and 2.20 mm Al, respectively. The HVL's were 5%-9% lower when measured with the Farmer chamber, as compared to measurements with the parallel plate chamber, for energies of 70 and 100 kV. Dose rates were also measured to be 3%-4% lower with the Farmer chamber. The dose rate variation between the two units was found to be 2%-9% for 50, 70, and 100 kV. The dose uniformity over a circle of 2 cm diameter was within 4% in four cardinal directions; however, the dose profiles for the 5 cm applicator were nonuniform, especially in the cathode-anode direction. Measurements indicated as much as 15% lower dose for the 50 kV beam at field edge on the anode side, when normalized to the center. The crossline profile was relatively more symmetric, with a maximum deviation of 10% at the field edge. All ion chamber readings agreed with film measurements within 3%. The nonuniform profile produced by these units may introduce uncertainty in dose rate measurements, especially for larger applicators. Since there is no intrinsic tool (crosshair or field light) for alignment with the beam axis, the user should take care when positioning the chamber for output measurements. The data obtained with a Farmer-type chamber should be used cautiously and as a reference only for the SRT-100 X-ray treatment unit. PMID:26103186

  13. The behavioral medicine unit: a community hospital model for inpatient treatment of adolescent depression.

    PubMed

    Greydanus, D E; Porter, J; Rypma, C B; Heuer, T; Granberg, A; Ruch, R

    1986-12-01

    This article describes one community hospital's response to the overwhelming needs of adolescents in central Iowa. It is based on the premise that many youths who have severe depression do not effectively respond to various outpatient counseling measures, and are in need of some type of inpatient treatment. Most such programs are locked psychiatric units run by child or adolescent psychiatrists. In our case, those wards already in existence are filled to capacity and cannot respond to outside needs. Placing these youth on traditional medical adolescent wards does not work, since medical staff are usually not geared to deal with the many, ever-changing mental health needs of these patients. Thus, we developed an unlocked adolescent inpatient unit with a pediatrician experienced in adolescent medicine as medical director; moreover, the program extensively utilizes psychologists, nurse-counselors, social worker-family therapists, recreation therapists, and other specialists. This program is a way for physicians trained in adolescent medicine and other appropriate persons to contribute to the complex health needs of youth; it is preferable to do this rather than send all depressed teenagers away by referrals, as seems to happen in some cases. It is also an important way for physicians and other specialists to demonstrate their expertise--both the Society for Adolescent Medicine and American Academy of Pediatrics have advocated such a demonstration--and to give physicians important training in the medical and mental health care needs of youth. Finally, the Spectrum Unit program provides a meaningful way for the primary care physician to be involved in the inpatient treatment of depressed adolescent patients.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3602650

  14. Multibeam tomotherapy: a new treatment unit devised for multileaf collimation, intensity-modulated radiation therapy.

    PubMed

    Achterberg, Nils; Müller, Reinhold G

    2007-10-01

    A fully integrated system for treatment planning, application, and verification for automated multileaf collimator (MLC) based, intensity-modulated, image-guided, and adaptive radiation therapy (IMRT, IGRT and ART, respectively) is proposed. Patient comfort, which was the major development goal, will be achieved through a new unit design and short treatment times. Our device for photon beam therapy will consist of a new dual energy linac with five fixed treatment heads positioned evenly along one plane but one electron beam generator only. A minimum of moving parts increases technical reliability and reduces motion times to a minimum. Motion is allowed solely for the MLCs, the robotic patient table, and the small angle gantry rotation of +/- 36 degrees. Besides sophisticated electron beam guidance, this compact setup can be built using existing modules. The flattening-filter-free treatment heads are characterized by reduced beam-on time and contain apertures restricted in one dimension to the area of maximum primary fluence output. In the case of longer targets, this leads to a topographic intensity modulation, thanks to the combination of "step and shoot" MLC delivery and discrete patient couch motion. Owing to the limited number of beam directions, this multislice cone beam serial tomotherapy is referred to as "multibeam tomotherapy." Every patient slice is irradiated by one treatment head at any given moment but for one subfield only. The electron beam is then guided to the next head ready for delivery, while the other heads are preparing their leaves for the next segment. The "Multifocal MLC-positioning" algorithm was programmed to enable treatment planning and optimize treatment time. We developed an overlap strategy for the longitudinally adjacent fields of every beam direction, in doing so minimizing the field match problem and the effects of possible table step errors. Clinical case studies show for the same or better planning target volume coverage, better

  15. Multibeam tomotherapy: A new treatment unit devised for multileaf collimation, intensity-modulated radiation therapy

    SciTech Connect

    Achterberg, Nils; Mueller, Reinhold G.

    2007-10-15

    A fully integrated system for treatment planning, application, and verification for automated multileaf collimator (MLC) based, intensity-modulated, image-guided, and adaptive radiation therapy (IMRT, IGRT and ART, respectively) is proposed. Patient comfort, which was the major development goal, will be achieved through a new unit design and short treatment times. Our device for photon beam therapy will consist of a new dual energy linac with five fixed treatment heads positioned evenly along one plane but one electron beam generator only. A minimum of moving parts increases technical reliability and reduces motion times to a minimum. Motion is allowed solely for the MLCs, the robotic patient table, and the small angle gantry rotation of {+-}36 deg. . Besides sophisticated electron beam guidance, this compact setup can be built using existing modules. The flattening-filter-free treatment heads are characterized by reduced beam-on time and contain apertures restricted in one dimension to the area of maximum primary fluence output. In the case of longer targets, this leads to a topographic intensity modulation, thanks to the combination of 'step and shoot' MLC delivery and discrete patient couch motion. Owing to the limited number of beam directions, this multislice cone beam serial tomotherapy is referred to as 'multibeam tomotherapy.' Every patient slice is irradiated by one treatment head at any given moment but for one subfield only. The electron beam is then guided to the next head ready for delivery, while the other heads are preparing their leaves for the next segment. The 'Multifocal MLC-positioning' algorithm was programmed to enable treatment planning and optimize treatment time. We developed an overlap strategy for the longitudinally adjacent fields of every beam direction, in doing so minimizing the field match problem and the effects of possible table step errors. Clinical case studies show for the same or better planning target volume coverage, better

  16. SU-E-P-45: An Analytical Formula for Deriving Mechanical Iso-Center of Rotational Gantry Treatment Unit Rotational Gantry Treatment Unit

    SciTech Connect

    Ding, X; Bues, M

    2015-06-15

    Purpose: To present an analytical formula for deriving mechanical isocenter (MIC) of a rotational gantry treatment unit. The input data to the formula is obtained by a custom-made device. The formula has been implemented and used in an operational proton therapy facility since 2005. Methods: The custom made device consisted of 3 mutually perpendicular dial indicators and 5 clinometers, to obtain displacement data and gantry angle data simultaneously. During measurement, a steel sphere was affixed to the patient couch, and the device was attached to the snout rotating with the gantry. The displacement data and angle data were obtained simultaneously at angular increments of less than 1 degree. The analytical formula took the displacement and angle as input and derived the positions of dial indicator tips (DIT) position in room-fixed coordinate system. The formula derivation presupposes trigonometry and 3-dimentional coordinate transformations. Due to the symmetry properties of the defining equations, the DIT position can be solved for analytically without using mathematical approximations. We define the mean of all points in the DIT trajectory as the MIC. The formula was implemented in computer code, which has been employed during acceptance test, commissioning, as well as routine QA practice in an operational proton facility since 2005. Results: It took one minute for the custom-made device to acquire the measurement data for a full gantry rotation. The DIT trajectory and MIS are instantaneously available after the measurement. The MIC Result agrees well with vendor’s Result, which came from a different measurement setup, as well as different data analysis algorithm. Conclusion: An analytical formula for deriving mechanical isocenter was developed and validated. The formula is considered to be absolutely accurate mathematically. Be analyzing measured data of radial displacements as function of gantry angle, the formula calculates the MI position in room

  17. Removal of dissolved organic matter in municipal effluent with ozonation, slow sand filtration and nanofiltration as high quality pre-treatment option for artificial groundwater recharge.

    PubMed

    Linlin, Wu; Xuan, Zhao; Meng, Zhang

    2011-04-01

    In the paper the combination process of ozonation, slow sand filtration (SSF) and nanofiltration (NF) was investigated with respect to dissolved organic matter (DOM) removal as high quality pre-treatment option for artificial groundwater recharge. With the help of ozonation leading to breakdown of the large organic molecules, SSF preferentially removes soluble microbial by-product-like substances and DOM with molecular weight (MW) less than 1.0 kDa. NF, however, removes aromatic, humic acid-like and fulvic acid-like substances efficiently and specially removes DOM with MW above 1.0 kDa. The residual DOM of the membrane permeate is dominated by small organics with MW 500 Da, which can be further reduced by the aquifer treatment, despite of the very low concentration. Consequently, the O(3)/SSF/NF system offers a complementary process in DOM removal. Dissolved organic carbon (DOC) and trihalomethane formation potential (THMFP) can be reduced from 6.5±1.1 to 0.7±0.3 mg L(-1) and from 267±24 to 52±6 μg L(-1), respectively. The very low DOC concentration of 0.6±0.2 mg L(-1) and THMFP of 44±4 μg L(-1) can be reached after the aquifer treatment. PMID:21382634

  18. A GIS COST MODEL TO ASSESS THE AVAILABILITY OF FRESHWATER, SEAWATER, AND SALINE GROUNDWATER FOR ALGAL BIOFUEL PRODUCTION IN THE UNITED STATES

    SciTech Connect

    Venteris, Erik R.; Skaggs, Richard; Coleman, Andre M.; Wigmosta, Mark S.

    2013-03-15

    A key advantage of using microalgae for biofuel production is the ability of some algal strains to thrive in waters unsuitable for conventional crop irrigation such as saline groundwater or seawater. Nonetheless, the availability of sustainable water supplies will provide significant challenges for scale-up and development of algal biofuels. We conduct a limited techno-economic assessment based on the availability of freshwater, saline groundwater, and seawater for use in open pond algae cultivation systems. We explore water issues through GIS-based models of algae biofuel production, freshwater supply, and cost models for supplying seawater and saline groundwater. We estimate that combined, within the coterminous US these resources can support production on the order of 9.46E+7 m3 yr-1 (25 billion gallons yr-1) of renewable biodiesel. Achievement of larger targets requires the utilization of less water efficient sites and relatively expensive saline waters. Geographically, water availability is most favorable for the coast of the Gulf of Mexico and Florida peninsula, where evaporation relative to precipitation is moderate and various saline waters are economically available. As a whole, barren and scrub lands of the southwestern US have limited freshwater supplies so accurate assessment of alternative waters is critical.

  19. Process engineering design of pathological waste incinerator with an integrated combustion gases treatment unit.

    PubMed

    Shaaban, A F

    2007-06-25

    Management of medical wastes generated at different hospitals in Egypt is considered a highly serious problem. The sources and quantities of regulated medical wastes have been thoroughly surveyed and estimated (75t/day from governmental hospitals in Cairo). From the collected data it was concluded that the most appropriate incinerator capacity is 150kg/h. The objective of this work is to develop the process engineering design of an integrated unit, which is technically and economically capable for incinerating medical wastes and treatment of combustion gases. Such unit consists of (i) an incineration unit (INC-1) having an operating temperature of 1100 degrees C at 300% excess air, (ii) combustion-gases cooler (HE-1) generating 35m(3)/h hot water at 75 degrees C, (iii) dust filter (DF-1) capable of reducing particulates to 10-20mg/Nm(3), (iv) gas scrubbers (GS-1,2) for removing acidic gases, (v) a multi-tube fixed bed catalytic converter (CC-1) to maintain the level of dioxins and furans below 0.1ng/Nm(3), and (vi) an induced-draft suction fan system (SF-1) that can handle 6500Nm(3)/h at 250 degrees C. The residence time of combustion gases in the ignition, mixing and combustion chambers was found to be 2s, 0.25s and 0.75s, respectively. This will ensure both thorough homogenization of combustion gases and complete destruction of harmful constituents of the refuse. The adequate engineering design of individual process equipment results in competitive fixed and operating investments. The incineration unit has proved its high operating efficiency through the measurements of different pollutant-levels vented to the open atmosphere, which was found to be in conformity with the maximum allowable limits as specified in the law number 4/1994 issued by the Egyptian Environmental Affairs Agency (EEAA) and the European standards. PMID:17166659

  20. Groundwater pumping by heterogeneous users

    NASA Astrophysics Data System (ADS)

    Saak, Alexander E.; Peterson, Jeffrey M.

    2012-08-01

    Farm size is a significant determinant of both groundwater-irrigated farm acreage and groundwater-irrigation-application rates per unit land area. This paper analyzes the patterns of groundwater exploitation when resource users in the area overlying a common aquifer are heterogeneous. In the presence of user heterogeneity, the common resource problem consists of inefficient dynamic and spatial allocation of groundwater because it impacts income distribution not only across periods but also across farmers. Under competitive allocation, smaller farmers pump groundwater faster if farmers have a constant marginal periodic utility of income. However, it is possible that larger farmers pump faster if the Arrow-Pratt coefficient of relative risk-aversion is sufficiently decreasing in income. A greater farm-size inequality may either moderate or amplify income inequality among farmers. Its effect on welfare depends on the curvature properties of the agricultural output function and the farmer utility of income. Also, it is shown that a flat-rate quota policy that limits the quantity of groundwater extraction per unit land area may have unintended consequences for the income distribution among farmers.

  1. Groundwater Screen

    Energy Science and Technology Software Center (ESTSC)

    1993-11-09

    GWSCREEN was developed for assessment of the groundwater pathway from leaching of radioactive and non radioactive substances from surface or buried sources and release to percolation ponds. The code calculates the limiting soil concentration or effluent release concentration such that, after leaching and transport to the aquifer, regulatory contaminant levels in groundwater are not exceeded. The code uses a mass conservation approach to model three processes: Contaminant release from a source volume, contaminant transport inmore » the unsaturated zone, and contaminant transport in the saturated zone. The source model considers the sorptive properties and solubility of the contaminant. Transport in the unsaturated zone is described by a plug flow model. Transport in the saturated zone is calculated with a semi-analytical solution to the advection dispersion equation in groundwater. Concentration as a function of time at a user specified receptor point and maximum concentration averaged over the exposure interval are also calculated. In addition, the code calculates transport and impacts of radioactive progeny. Input to GWSCREEN is through one, free format ASCII file. This code was designed for assessment and screening of the groundwater pathway when field data is limited. It was not intended to be a predictive tool.« less

  2. Treatment Adherence of Tuberculosis Patients Attending Two Reference Units in Equatorial Guinea.

    PubMed

    Fagundez, Gabriela; Perez-Freixo, Hugo; Eyene, Juan; Momo, Juan Carlos; Biyé, Lucia; Esono, Teodoro; Ondó Mba Ayecab, Marcial; Benito, Agustín; Aparicio, Pilar; Herrador, Zaida

    2016-01-01

    Equatorial Guinea has one of the highest burden of tuberculosis (TB) in Africa. Incomplete adherence to TB treatment has been identified as one of the most serious remaining problem in tuberculosis control. The following study is aimed at determining the adherence to anti-tuberculosis treatment in Equatorial Guinea and its determinants, as well as at assessing the knowledge of the people about the disease. In this cross-sectional study, participants were recruited by non-probabilistic consecutive sampling amongst patients who attended the reference units for TB in Bata and Malabo between March and July 2015. Socio-demographic and clinical data were collected. Adherence to treatment and knowledge about TB were assessed by Morisky-Green-Levine and Batalla tests and a questionnaire on adherence related factors specifically prepared for this research. Descriptive statistics were computed to summarize the data and bivariate analyses by adherence profile were performed with χ2 test for categorical data. A total of 98 patients with TB were interviewed. 63.27% of interviewees had good knowledge about TB (Batalla test) while 78.57% of respondents were adherent according to the Morisky-Green-Levine test. A low educational level, lack of family support and lack of medical advice about the disease were significantly associated to lower adherence level. Patients with re-infection (due to relapse or treatment failure) and those who have suffered from drug shortages were also less adherents. The National Programme for TB Control should consider improving the early diagnosis and follow-up of TB cases, as well as the implementation of all components of DOTS (Directly observed Treatment, short-course) strategy all over the country. PMID:27622461

  3. Usefulness of hounsfield unit and density in the assessment and treatment of urinary stones

    PubMed Central

    Gücük, Adnan; Üyetürk, Uğur

    2014-01-01

    Computed tomography (CT) is widely used to examine stones in the urinary system. In addition to the size and location of the stone and the overall health of the kidney, CT can also assess the density of the stone in Hounsfield units (HU). The HU, or Hounsfield density, measured by CT, is related to the density of the tissue or stone. A number of studies have assessed the use of HU in urology. HUs have been used to predict the type and opacity of stones during diagnosis, and the efficacy has been assessed using methods including extracorporeal shock wave lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL), ureterorenoscopic ureterolithotripsy (URSL), and medical expulsive treatment (MET). Previous studies have focused on the success rate of HU for predicting the type of stone and of ESWL treatment. Understanding the composition of the stone plays a key role in determining the most appropriate treatment modality. The most recent reports have suggested that the HU value and its variants facilitate prediction of stone composition. However, the inclusion of data regarding urine, such as pH and presence of crystals, increases the predictive accuracy. HUs, which now form part of the clinical guidelines, allow us to predict the success of ESWL; therefore, they should be taken into account when ESWL is considered as a treatment option. However, there are currently insufficient data available regarding the value of HU for assessing the efficacy of PCNL, URSL, and MET. Studies performed to date suggest that these values would make a significant contribution to the diagnosis and treatment of urinary system stones. However, more data are required to assess this further. PMID:25374823

  4. Reassessment of the effects of construction dewatering on ground-water levels in the Cowles Unit, Indiana Dunes National Lakeshore, Indiana : Supplement to Geological Survey Water Resources Investigations 78-138

    USGS Publications Warehouse

    Gillies, Daniel C.; Lapham, Wayne W.

    1980-01-01

    A revised dewatering plan for the construction of a nuclear power plant at the Northern Indiana Public Service Company 's (NIPSCO) Bailly Generating Station and evidence that suggests that a change in the characteristics of the confining unit 2 in and near Cowles Bog National Landmark may exist have resulted in a reassessment of the effects of construction dewatering on ground-water levels in the Indiana Dunes National Lakeshore. Model results indicate that the revision in the dewatering plan produces water-level declines that do not differ significantly from those described previously. However, when the change in the confining unit beneath Cowles Bog is considered, simulations of the simultaneous decline of a seepage mound after sealing of the fly-ash-ponds and the second phase of construction dewatering indicate that the simulated water-level declines in the aquifer unit 1 at Cowles Bog may be below the water levels tolerated by the National Park Service after 18 months. The water levels may even decline below the tolerable levels in spite of NIPSCO 's proposed plan of artificially recharging the aquifer unit 1 near the excavation site at 400 gal/min. The magnitude of the simulated water-level declines in unit 1 within the Lakeshore, caused by pumping from the excavation, depends on the relation in time between the second phase of dewatering and the decline of the seepage mound after sealing of the fly-ash-ponds, but not on the duration of dewatering beyond 18 months. (USGS)

  5. Importance of radiant flux in the treatment of hyperbilirubinemia: failure of overhead phototherapy units in intensive care units.

    PubMed

    Bonta, B W; Warshaw, J B

    1976-04-01

    Prior to 1972, radiation used to treat neonatal hyperbilirubinemia was based upon the photometric unit, the foot-candle, a measure of light illumination. Measurements in terms of microwatts per square centimeter for selective wavelengths is more precise. We compared the effectiveness of phototherapy provided by overhead phototherapy units in intensive care modules vs. conventional phototherapy units. Forty-two infants were studied over a six-month period and divided into three groups based upon radiant flux measurements as follows: Group 1 (No. = 6), 1.0 muw to 1.9 muw/sq cm/nm; group 2 (No. = 15), 2.0 muw to 3.9 muw/sq cm/nm; group 3 (No. = 21), 4.0 muw to 6.0 muw/sq cm/nm. All flux determinations were made within the 400- to 500-nm range. All infants in group 1 were treated with overhead phototherapy units in the intensive care modules. Because of multiple factors known to increase the risk of kernicterus, evaluation of effectiveness of phototherapy at low radiant flux was limited in group 1. Significant changes in bilirubin were noted by 48 hours when comparing group 3 with groups 1 and 2. A minimum of 4.0 muw/sq cm/nm appears necessary for effective phototherapy. As designed, phototherapy units in intensive care modules are ineffective in delivering this therapeutic level of radiant flux. PMID:1264545

  6. Fifteen-year Assessment of a Permeable Reactive Barrier for Treatment of Chromate and Trichloroethylene in Groundwater

    EPA Science Inventory

    The fifteen-year performance of a granular iron, permeable reactive barrier (PRB; Elizabeth City, North Carolina) is reviewed with respect to contaminant treatment (hexavalent chromium and trichloroethylene) and hydraulic performance. Due to in-situ treatment of the chromium sou...

  7. Status of groundwater quality in the Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts study unit, 2008-2010: California GAMA Priority Basin Project

    USGS Publications Warehouse

    Parsons, Mary C.; Hancock, Tracy Connell; Kulongoski, Justin T.; Belitz, Kenneth

    2014-01-01

    Groundwater quality in the approximately 963-square-mile Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts study unit was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is located in southern California in San Bernardino, Riverside, San Diego, and Imperial Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey and the Lawrence Livermore National Laboratory. The GAMA Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts study was designed to provide a spatially unbiased assessment of the quality of untreated (raw) groundwater in the primary aquifer system. The assessment is based on water-quality and ancillary data collected by the U.S. Geological Survey from 52 wells (49 grid wells and 3 understanding wells) and on water-quality data from the California Department of Public Health database. The primary aquifer system was defined by the depth intervals of the wells listed in the California Department of Public Health database for the Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts study unit. The quality of groundwater in the primary aquifer system may be different from that in the shallower or deeper water-bearing zones; shallow groundwater may be more vulnerable to surficial contamination. This study assesses the status of the current quality of the groundwater resource by using data from samples analyzed for volatile organic compounds (VOCs), pesticides, and naturally occurring inorganic constituents, such as major ions and trace elements. This status assessment is intended to characterize the quality of groundwater resources in the primary aquifer system of the Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts study unit, not the

  8. Groundwater impact assessment report for the 100-D Ponds

    SciTech Connect

    Alexander, D.J.

    1993-07-01

    The 183-D Water Treatment Facility (WTF) discharges effluent to the 120-0-1 Ponds (100-D Ponds) located north of the 100-D Area perimeter fence. This report satisfies one of the requirements of the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) Milestone M-17-00B as agreed by the US Department of Energy, Washington State Department of Ecology, and the US Environmental Protection Agency. Tri-Party Agreement Milestone M-17-00B includes a requirement to assess impacts to groundwater from disposal of the 183-D WTF effluent to the 100-D Ponds. In addition, the 100-D Ponds are a Resource Conservation and Recovery Act of 1976 treatment, storage, and disposal facility covered by the 100-D Ponds Closure Plan (DOE-RL 1993a). There is evidence of groundwater contamination, primarily nitrate, tritium, and chromium, in the unconfined aquifer beneath the 100-D Area and 100 Areas in general. The contaminant plumes are area wide and are a result of past-practice reactor and disposal operations in the 100-D Area currently being investigated as part of the 100-DR-1 and 100-HR-3 Operable Units (DOE-RL 1992b, 1992a). Based on current effluent conditions, continued operation of the 100-D Ponds will not adversely affect the groundwater quality in the 100-D Area. Monitoring wells near the pond have slightly higher alkaline pH values than wells in the rest of the area. Concentrations of known contaminants in these wells are lower than ambient 100-D Area groundwater conditions and exhibit a localized dilution effect associated with discharges to the pond. Hydraulic impact to the local groundwater system from these discharges is minor. The groundwater monitoring well network for the 100-D Ponds is adequate.

  9. Treatment and diagnostic accuracy of neurosyphilis at Boston City Hospital's Neurological Unit, 1930-1979.

    PubMed

    Patterson, Diana; Vilensky, Joel A; Robertson, Wendy M; Berger, Joseph

    2012-03-15

    The twentieth century was marked with frequent advances in the treatment and diagnosis of neurosyphilis. Once considered one of the most serious human diseases, neurosyphilis was paramount to a death sentence often preceded by agonizing pain and/or diminishing mental capacities. Since the introduction of penicillin in 1943, however, the prevalence of neurosyphilis has declined dramatically and the prognosis of the few still affected has been greatly improved. We examined patient records from Boston City Hospital's (BCH) Neurologic Unit from 1930 to 1979 to obtain primary data on treatment modalities for neurosyphilis during this period, with particular attention to the use of malarial therapy. We also evaluated these same records to determine whether the "great imitator" moniker that was applied to neurosyphilis may have in part been due to systematic errors in diagnostic criteria and false positive tests. The BCH neurologists used all available treatment compounds, including arsenicals, bismuth, iodides, malaria, and typhoid. The data also suggest that the wide diversity of symptoms attributed to neurosyphilis was probably accurate. PMID:22129939

  10. Treatment of severe perinatal mood disorders on a specialized perinatal psychiatry inpatient unit.

    PubMed

    Kimmel, Mary C; Lara-Cinisomo, S; Melvin, K; Di Florio, A; Brandon, A; Meltzer-Brody, S

    2016-08-01

    Perinatal patients with bipolar and psychotic mood disorder exacerbations are challenging to treat and often receive suboptimal care. We sought to examine the treatment patterns and outcomes on one of the only US-based Perinatal Psychiatry Inpatient Units (PPIU). Perinatal patients admitted to the PPIU completed self-report measures at admission and before discharge. Retrospective chart reviews extracted history, diagnoses (current and past), and medication treatment. Patients who had discharge diagnoses of bipolar disorder, major depression with psychotic features, or postpartum psychosis were included. Forty-seven met the diagnostic inclusion criteria. Over an average length of stay (ALOS) of 9.96 days, there was significant improvement in depressive and anxiety symptoms and daily functioning (Work and Social Adjustment Scale). Psychiatric comorbidity was common. Polypharmacy was utilized in 87 %. The most common medications prescribed at discharge were antipsychotics, alone or in combination with mood stabilizers or antidepressants. ECT was performed in 10 % of cases. The complexity of patients with severe mood disorders or psychosis admitted to the PPIU supports individualized treatment plans that address both primary diagnosis and psychiatric comorbidities. Our results provide important information that can be disseminated to others to improve clinical outcomes for severe perinatal mood disorders. PMID:26802019

  11. Handover of patient information from the crisis assessment and treatment team to the inpatient psychiatric unit.

    PubMed

    Waters, Amanda; Sands, Natisha; Keppich-Arnold, Sandra; Henderson, Kathryn

    2015-06-01

    Handover, or the communication of patient information between clinicians, is a fundamental component of health care. Psychiatric settings are dynamic environments relying on timely and accurate communication to plan care and manage risk. Crisis assessment and treatment teams are the primary interface between community and mental health services in many Australian and international health services, facilitating access to assessment, treatment, and admission to hospital. No previous research has investigated the handover between crisis assessment and treatment teams and inpatient psychiatric units, despite the importance of handover to care planning. The aim of the present study was to identify the nature and types of information transferred during these handovers, and to explore how these guides initial care planning. An observational, exploratory study design was used. A 20-item handover observation tool was used to observe 19 occasions of handover. A prospective audit was undertaken on clinical documentation arising from the admission. Clinical information, including psychiatric history and mental state, were handed over consistently; however, information about consumer preferences was reported less consistently. The present study identified a lack of attention to consumer preferences at handover, despite the current focus on recovery-oriented models for mental health care, and the centrality of respecting consumer preferences within the recovery paradigm. PMID:25438620

  12. Sexual orientation and substance abuse treatment utilization in the United States: results from a national survey.

    PubMed

    McCabe, Sean Esteban; West, Brady T; Hughes, Tonda L; Boyd, Carol J

    2013-01-01

    This study examined substance abuse treatment utilization across three dimensions of sexual orientation (identity, attraction, and behavior) in a large national sample of adults in the United States. Prevalence estimates were based on data collected from the 2004-2005 National Epidemiologic Survey on Alcohol and Related Conditions. The sample consisted of 34,653 adults 20 years and older, and represented a population that was 52% women, 71% White, 12% Hispanic, 11% African American, 4% Asian, and 2% other race/ethnicities. An estimated 2% of the target population self-identified as lesbian, gay or bisexual; 4% reported same-sex sexual behavior, and 6% reported same-sex sexual attraction. Sexual minorities, especially women, had a greater likelihood of lifetime substance use disorders and earlier age of drinking onset. The majority of respondents with substance use disorders were untreated and lifetime substance abuse treatment utilization differed based on sexual orientation. Sexual minorities were found to have more extensive family histories of substance abuse problems. The findings indicate the underutilization of substance abuse treatment among all adults, and highlight some important factors to consider when working with sexual minorities. PMID:22444421

  13. United Nations Office on Drugs and Crime International Network of Drug Dependence Treatment and Rehabilitation Resource Centres: Treatnet

    ERIC Educational Resources Information Center

    Tomas-Rossello, Juana; Rawson, Richard A.; Zarza, Maria J.; Bellows, Anne; Busse, Anja; Saenz, Elizabeth; Freese, Thomas; Shawkey, Mansour; Carise, Deni; Ali, Robert; Ling, Walter

    2010-01-01

    Key to the dissemination of evidence-based addiction treatments is the exchange of experiences and mutual support among treatment practitioners, as well as the availability of accurate addiction training materials and effective trainers. To address the shortage of such resources, the United Nations Office on Drugs and Crime (UNODC) created…

  14. Polymer treatments for D Sand water injection wells: Sooner D Sand Unit Weld County, Colorado. Final report, April 1997

    SciTech Connect

    Cannon, T.J.

    1998-10-01

    Polymer-gel treatments in injection wells were evaluated for improving sweep efficiency in the D Sandstone reservoir at the Sooner Unit, Weld County, Colorado. Polymer treatments of injection wells at the Sooner Unit were expected to improve ultimate recovery by 1.0 percent of original-oil-in-place of 70,000 bbl of oil. The Sooner D Sand Unit was a demonstration project under the US Department of Energy Class I Oil Program from which extensive reservoir data and characterization were obtained. Thus, successful application of polymer-gel treatments at the Sooner Unit would be a good case-history example for other operators of waterfloods in Cretaceous sandstone reservoirs in the Denver Basin.

  15. Residential treatment centers and other organized mental health care for children and youth: United States, 1988.

    PubMed

    Sunshine, J H; Witkin, M J; Atay, J E; Manderscheid, R W

    1991-07-01

    Residential treatment centers (RTCs) for emotionally disturbed children are an important component of the mental health services delivery system in the United States. The 440 RTCs operating in 1988 represented 9 percent of all mental health organizations in the U.S. in that year. They served approximately 10 percent of the patients who received inpatient and residential treatment care and approximately 2 percent of outpatient psychiatric visits in organized settings. Their 39,000 full-time equivalent (FTE) staff and $1.3 billion expenditures were, respectively, 7 percent and 6 percent of the total for all mental health organizations. Between 1986 and 1988, the number of RTCs increased slightly, while the volume of residential treatment care changed little. However, partial care and outpatient care expanded in RTCs, with the number of visits in these categories increasing by 75 percent and 42 percent, respectively. FTE staff grew by 13 percent, and expenditures increased by 33 percent between 1986 and 1988. In 1988, RTCs were located in all States except North Dakota. The largest number were found in California (48), Massachusetts (38), and New York (28). By definition, all RTCs provided residential treatment care. About one-third of them also provided partial care and one-third provided outpatient care. The highest rates of additions to residential treatment care in RTCs per 100,000 civilian population were found in Minnesota and Colorado. Reflecting the role of RTCs as providers of care to children and youth, 94 percent of residential treatment patients in RTCs were under age 18. Seventy percent of residential treatment patients were male; 28 percent, black; and 10 percent, Hispanic. Approximately 94 percent had mental illness as their principal disability. In December 1988, 43,000 staff worked in RTCs; 14 percent were employed part-time, and 3 percent were trainees. Among others, the staff included approximately 900 psychiatrists, 300 other physicians, 1

  16. HANFORD GROUNDWATER REMEDIATION

    SciTech Connect

    CHARBONEAU, B; THOMPSON, M; WILDE, R.; FORD, B.; GERBER, M.S.

    2006-02-01

    united in its desire to protect the Columbia River and have a voice in Hanford's future. This paper presents the challenges, and then discusses the progress and efforts underway to reduce the risk posed by contaminated groundwater at Hanford. While Hanford groundwater is not a source of drinking water on or off the Site, there are possible near-shore impacts where it flows into the Columbia River. Therefore, this remediation is critical to the overall efforts to clean up the Site, as well as protect a natural resource.

  17. Hanford Groundwater Remediation

    SciTech Connect

    Charboneau, B.; Thompson, K. M.; Wilde, R.; Ford, B.; Gerber, M.

    2006-07-01

    united in its desire to protect the Columbia River and have a voice in Hanford's future. This paper presents the challenges, and then discusses the progress and efforts underway to reduce the risk posed by contaminated groundwater at Hanford. While Hanford groundwater is not a source of drinking water on or off the Site, there are possible near-shore impacts where it flows into the Columbia River. Therefore, this remediation is critical to the overall efforts to clean up the Site, as well as protect a natural resource. (authors)

  18. Grand Junction projects office mixed-waste treatment program, VAC*TRAX mobile treatment unit process hazards analysis

    SciTech Connect

    Bloom, R.R.

    1996-04-01

    The objective of this report is to demonstrate that a thorough assessment of the risks associated with the operation of the Rust Geotech patented VAC*TRAX mobile treatment unit (MTU) has been performed and documented. The MTU was developed to treat mixed wastes at the US Department of Energy (DOE) Albuquerque Operations Office sites. The MTU uses an indirectly heated, batch vacuum dryer to thermally desorb organic compounds from mixed wastes. This process hazards analysis evaluated 102 potential hazards. The three significant hazards identified involved the inclusion of oxygen in a process that also included an ignition source and fuel. Changes to the design of the MTU were made concurrent with the hazard identification and analysis; all hazards with initial risk rankings of 1 or 2 were reduced to acceptable risk rankings of 3 or 4. The overall risk to any population group from operation of the MTU was determined to be very low; the MTU is classified as a Radiological Facility with low hazards.

  19. AMBULATORY DIAGNOSIS AND TREATMENT OF NON-MALIGNANT PAIN IN THE UNITED STATES, 2000–2010

    PubMed Central

    Daubresse, Matthew; Chang, Hsien-Yen; Yu, Yuping; Viswanathan, Shilpa; Shah, Nilay D.; Stafford, Randall S.; Kruszewski, Stefan P.; Alexander, G. Caleb

    2013-01-01

    Background Escalating rates of prescription opioid use and abuse have occurred in the context of efforts to improve the treatment of non-malignant pain. Objectives To characterize the diagnosis and management of non-malignant pain in ambulatory, office-based settings in the United States between 2000 and 2010. Design, setting, and participants Serial cross-sectional and multivariate regression analyses of the National Ambulatory Medical Care Survey (NAMCS), a nationally representative audit of office-based physician visits. Measures (1) Annual visits volume among adults with primary pain symptom or diagnosis; (2) receipt of any pain treatment; and (3) receipt of prescription opioid or non-opioid pharmacologic therapy in visits for new musculoskeletal pain. Results Primary symptoms or diagnoses of pain consistently represented one-fifth of visits, varying little from 2000 through 2010. Among all pain visits, opioid prescribing nearly doubled from 11.3% to 19.6%, whereas non-opioid analgesic prescribing remained unchanged (26%–29% of visits). One-half of new musculoskeletal pain visits resulted in pharmacologic treatment, though the prescribing of non-opioid pharmacotherapies decreased from 38% of visits (2000) to 29% of visits (2010). After adjusting for potentially confounding covariates, few patient, physician or practice characteristics were associated with a prescription opioid rather than a non-opioid analgesic for new musculoskeletal pain, and increases in opioid prescribing generally occurred non-selectively over time. Conclusions Increased opioid prescribing has not been accompanied by similar increases in non-opioid analgesics or the proportion of ambulatory pain patients receiving pharmacologic treatment. Clinical alternatives to prescription opioids may be underutilized as a means of treating ambulatory non-malignant pain. PMID:24025657

  20. Trends in osteoporosis treatment with oral and intravenous bisphosphonates in the United States, 2002-2012.

    PubMed

    Wysowski, Diane K; Greene, Patty

    2013-12-01

    Bisphosphonates have been widely prescribed to postmenopausal women for treatment and prevention of osteoporosis. Given a background of reports of recent safety problems, questions about optimal duration of use, and the patent expiration of Fosamax in February 2008, we accessed data from pharmaceutical marketing research databases to describe trends in dispensed prescriptions and sales of oral bisphosphonates, characteristics of patients and prescribers, and sales of intravenous bisphosphonates for osteoporosis treatment. An estimated 21.3million prescriptions for oral bisphosphonates were dispensed in U.S. retail pharmacies in 2002 that increased 46% to a peak of 31.0million in 2007 and 2008, and declined by 53% in a four year-period to 14.7million in 2012. Sales data (number of packages sold in all settings of care) showed parallel trends (66% increase from 2002 through 2007 and 51% decrease from 2007 through 2012). Similarly, intravenous bisphosphonate sales for osteoporosis treatment grew 3.8-fold from 149.5 thousand packages in 2007 to 561.6 thousand in 2010, followed by a 22% decrease in 2012. Data from an ongoing monthly office-based survey indicated physicians mentioned oral bisphosphonates primarily in visits of older aged Caucasian women with lower body mass for osteoporosis. Frequencies of oral bisphosphonate mentions increased between 2002 and 2012 in visits of Asians and for osteopenia diagnoses. These data indicate a substantial decline in prescriptions and sales of oral (since 2007-2008) and intravenous (since 2010) bisphosphonates for osteoporosis treatment in the United States. Reasons for, and implications of, the decline should be considered for future research. PMID:24063946

  1. Prolonged Glucocorticoid Treatment in ARDS: Impact on Intensive Care Unit-Acquired Weakness

    PubMed Central

    Meduri, Gianfranco Umberto; Schwingshackl, Andreas; Hermans, Greet

    2016-01-01

    Systemic inflammation and duration of immobilization are strong independent risk factors for the development of intensive care unit-acquired weakness (ICUAW). Activation of the pro-inflammatory transcription factor nuclear factor-κB (NF-κB) results in muscle wasting during disuse-induced skeletal muscle atrophy (ICU bed rest) and septic shock. In addition, NF-κB-mediated signaling plays a significant role in mechanical ventilation-induced diaphragmatic atrophy and contractile dysfunction. Older trials investigating high dose glucocorticoid treatment reported a lack of a sustained anti-inflammatory effects and an association with ICUAW. However, prolonged low-to-moderate dose glucocorticoid treatment of sepsis and ARDS is associated with a reduction in NF-κB DNA-binding, decreased transcription of inflammatory cytokines, enhanced resolution of systemic and pulmonary inflammation, leading to fewer days of mechanical ventilation, and lower mortality. Importantly, meta-analyses of a large number of randomized controlled trials investigating low-to-moderate glucocorticoid treatment in severe sepsis and ARDS found no increase in ICUAW. Furthermore, while the ARDS network trial investigating methylprednisolone treatment in persistent ARDS is frequently cited to support an association with ICUAW, a reanalysis of the data showed a similar incidence with the control group. Our review concludes that in patients with sepsis and ARDS, any potential direct harmful neuromuscular effect of glucocorticoids appears outweighed by the overall clinical improvement and reduced duration of organ failure, in particular ventilator dependency and associated immobilization, which are key risk factors for ICUAW. PMID:27532030

  2. IN SITU FLOW METERS AROUND A GROUNDWATER CIRCULATION WELL (ABSTRACT)

    EPA Science Inventory

    The primary benefit of groundwater circulation well (GCW) technology is the development of strong vertical flows surrounding the treatment well. The extent of significant vertical flow surrounding a circulation well is difficult to establish from traditional groundwater elevation...

  3. IN SITU FLOW METERS AROUND A GROUNDWATER CIRCULATION WELL (PAPER)

    EPA Science Inventory

    The primary benefit of groundwater circulation well (GCW) technology is the development of strong vertical flows surrounding the treatment well. The extent of significant vertical flow surrounding a circulation well is difficult to establish from traditional groundwater elevation...

  4. [Technical aspects of treatments with single- and multi-unit fixed dental prostheses].

    PubMed

    Wiersema, E J; Kreulen, C M; Latzke, P; Witter, D J; Creugers, N H J

    2014-05-01

    For the manufacture of single- and multi-unit fixed dental prostheses, effective communication between dentist and dental technician is required. Mutual insight concerning the (im)possibilities of available treatments and technical options is prerequisitefor this communication. The manufacture of single- and multi-unit fixed dental prostheses involves 4 phases: recording the required detailed information on the relevant teeth and the occlusal system, the technical adjustments, the technical design and the technical fabrication. These phases can be accomplished through an analogue or (semi)digital procedure. Pioneering developments are computer aided design and computer aided manufacturing (CAD/CAM), and computerised milling machines. Associated with this are 3 manufacturing methods which can be distinguished: the dental practice method, the dental laboratory method and the milling centre method. Materials applied are metal alloys and ceramics, while resins are used for provisional and transitional constructions. Due to the fact that the choice of material in the analogue procedure is limited, CAD/CAM offers more options, the digital procedure is expected to gain ground gradually. It is expected that this development will provide an impulse to higher quality. PMID:24881256

  5. MODFLOW-2000, the U.S. Geological Survey modular ground-water model -- Documentation of the Model-Layer Variable-Direction Horizontal Anisotropy (LVDA) capability of the Hydrogeologic-Unit Flow (HUF) package

    USGS Publications Warehouse

    Anderman, Evan R.; Kipp, K.L.; Hill, Mary C.; Valstar, Johan; Neupauer, R.M.

    2002-01-01

    This report documents the model-layer variable-direction horizontal anisotropy (LVDA) capability of the Hydrogeologic-Unit Flow (HUF) Package of MODFLOW-2000. The LVDA capability allows the principal directions of horizontal anisotropy to be different than the model-grid row and column directions, and for the directions to vary on a cell-by-cell basis within model layers. The HUF Package calculates effective hydraulic properties for model grid cells based on hydraulic properties of hydrogeologic units with thicknesses defined independently of the model layers. These hydraulic properties include, among other characteristics, hydraulic conductivity and a horizontal anisotropy ratio. Using the LVDA capability, horizontal anisotropy direction is defined for model grid cells within which one or more hydrogeologic units may occur. For each grid cell, the HUF Package calculates the effective horizontal hydraulic conductivity along the primary direction of anisotropy using the hydrogeologic-unit hydraulic conductivities, and calculates the effective horizontal hydraulic conductivity along the orthogonal anisotropy direction using the effective primary direction hydraulic conductivities and horizontal anisotropy ratios. The direction assigned to the model layer effective primary hydraulic conductivity is specified using a new data set defined by the LVDA capability, when active, to calculate coefficients needed to solve the ground-water flow equation. Use of the LVDA capability is illustrated in four simulation examples, which also serve to verify hydraulic heads, advective-travel paths, and sensitivities calculated using the LVDA capability. This version of the LVDA capability defines variable-direction horizontal anisotropy using model layers, not the hydrogeologic units defined by the HUF Package. This difference needs to be taken into account when designing model layers and hydrogeologic units to produce simulations that accurately represent a given field problem. This

  6. Groundwater intrusion into leaky sewer systems.

    PubMed

    Wittenberg, H; Aksoy, H

    2010-01-01

    Vast volumes of groundwater are drained by urban sewer systems. This unwanted flow component intrudes into sewer systems through leaky joints or connected house drains. However, unlike urban storm drainage, it has a high seasonal variation corresponding to groundwater storage and long slow recessions similar to baseflow in rivers also fed by shallow groundwater exfiltrating into the surface waters. By applying the nonlinear reservoir algorithm as used for baseflow separation from total flow in a river, groundwater flow is separated from daily measured influents to treatment plants in Lower Saxony and Baden-Württemberg, Germany and in the Terkos Lake watershed near Istanbul, Turkey. While waste water flows vary only moderately within a year, separated intruded groundwater flows show recessions and seasonal variations correlated to baseflow in neighbouring rivers. It is possible to conclude that recession characteristics of treatment plant influents allow quantification and prediction of groundwater intrusion into sewer systems. PMID:20595758

  7. Groundwater workshops

    NASA Astrophysics Data System (ADS)

    The Interstate Conference on Water Policy has released an Executive Report of the 1989 Ground Water Information Management Workshops. The report summarizes workgroup findings and recommendations for action as identified at the four workshops conducted in the winter and spring of 1989 in Little Rock, Ark.; Sacramento, Calif.; Harrisburg, Pa.; and Omaha, Nebr. The workshops, cosponsored by ICWP and the U.S. Geological Survey, attracted over 200 participants from local, state, and federal government, academia, and the private sector.The two primary objectives of the workshop series were to provide participants with information about groundwater data management initiatives at all levels of government, and to elicit information and ideas from participants about improving data management and exchange. The report states that although the individual workshops reflected regional concerns and experiences, collectively they provide a solid foundation for developing a national perspective on groundwater information management needs.

  8. Maintenance of CO2 level in a BLSS by controlling solid waste treatment unit

    NASA Astrophysics Data System (ADS)

    Dong, Yingying; Li, Leyuan; Liu, Hong; Fu, Yuming; Xie, Beizhen; Hu, Dawei; Liu, Dianlei; Dong, Chen; Liu, Guanghui

    A bioregenerative life support system (BLSS) is an artificial closed ecosystem for providing basic human life support for long-duration, far-distance space explorations such as lunar bases. In such a system, the circulation of gases is one of the main factor for realizing a higher closure degree. O2 produced by higher plants goes to humans, as well as microorganisms for the treatment of inedible plant biomass and human wastes; CO2 produced by the crew and microorganisms is provided for plant growth. During this process, an excessively high CO2 level will depress plant growth and may be harmful to human health; and if the CO2 level is too low, plant growth will also be affected. Thus, keeping the balance between CO2 and O2 levels is a crucial problem. In this study, a high-efficiency, controllable solid waste treatment unit is constructed, which adopts microbial fermentation of the mixture of inedible biomass and human wastes. CO2 production during the fermentation process is controlled by adjusting fermentation temperature, aeration rate, moisture, etc., so as to meet the CO2 requirement of plants

  9. A ground-water model of the upper San Pedro Basin from the Mexico-United States International Boundary to Fairbank, Arizona

    USGS Publications Warehouse

    Freethey, G.W.

    1982-01-01

    A definition of the hydrologic system of the upper San Pedro basin was obtained by developing a numerical ground-water model to evaluate a conceptual model of the system. Information on hydraulic properties of the basin fill, recharge from bordering mountain ranges, discharge by evapotranspiration, and exchange of water between aquifer and stream was available from previous measurements or estimates. The steady-state calibration procedure and subsequent transient simulations demonstrated that the original conceptualization can be reasonably simulated. An analysis of model sensitivity to increases and decreases in certain hydraulic properties indicated a low sensitivity to aquifer anisotropy and a low to moderate sensitivity to stream leakance and evapotranspiration rate. An analysis to investigate the effects of generalizing aquifer conductivity and recharge showed that flow components and water-level response to stress could be simulated adequately but that steady-state water-level conditions could not. During equilibrium conditions, recharge to and discharge from the basin was about 16,500 acre-feet per year. Modeling results indicated that by 1978 the storage depletion rate had reached 5,600 acre-feet per year resulting from a ground-water withdrawal rate of 10,500 acre-feet per year. (USGS)

  10. Economic Impacts of Treatment for Type II or III Thoracoabdominal Aortic Aneurysm in the United States

    PubMed Central

    Vaislic, Mickael; Vaislic, Claude; Alsac, Jean-Marc; Benjelloun, Amira; Chocron, Sidney; Unterseeh, Thierry; Fabiani, Jean-Noel

    2014-01-01

    Background: Current treatment for extensive thoracoabdominal aortic aneurysms (TAAAs) involves high-risk surgical and endovascular repairs, with a hospital mortality exceeding 20%, and a postoperative paraplegia rate beyond 10.5%. Objectives: The aim of this study was to present an estimation of the economic impacts of surgical and endovascular treatments of types II and III TAAAs in the US as well as the economic consequences of the elimination of spinal cord injury and mortality via an endovascular repair of extensive TAAAs (1). Materials and Methods: We compared the current hospital charges of endovascular and surgical repair of extensive TAAAs, also provided a cost analysis of health care charges resulting from paraplegia in the United States, and determined the prevalence of extensive TAAAs found yearly during autopsies in the U.S. Based on the figures gathered and the frequency of Thoracic Aortic Aneurysms per year, we were able to calculate the nationwide inpatient hospital charges, the total average expenses affected by paraplegia during the first 12 months after the repair, the total average expenses after paraplegia for each subsequent year, mortality rate at 30 days and one year, and the number of extensive TAAAs ruptures. Results: The current nationwide inpatient hospital charges for type II or III TAAA repair cost $12484324 and $37612665 for endovascular repair and surgical repair respectively, and the total average expenses for patients affected by paraplegia during the first 12-month were $4882291 and $23179110 after endovascular repair and surgical repair respectively. The nationwide average expense after 10 years for patients undergoing surgical repair and affected by paraplegia is $33421910 and $6,316,183 for patients undergoing endovascular repair. Moreover, 55 patients with a type II or type III TAAA died after 30 days, and 100 after 1 year. The potential risk of type II or III TAAA ruptures is totally 1637 in a year. Conclusions: Major economic

  11. Identifying Groundwater Recharge in Arid Regions

    NASA Astrophysics Data System (ADS)

    Thomas, B. F.; Famiglietti, J. S.

    2015-12-01

    Recharge epodicity in arid regions provides a method to estimate annual groundwater recharge given a relationship expressed as the recharge to precipitation ratio. Traditionally, in-situ observations are required to identify aquifer recharge events, while more advanced approaches such as the water-table fluctuation method or the episodic master recession method are necessary to delineate the recharge event. Our study uses the Gravity Recovery and Climate Experiment (GRACE) observations to estimate monthly changes in groundwater storage which are attributed to the combination of groundwater abstraction and episodic recharge in the arid southwestern United States. Our results illustrate the ability of remote sensing technologies to identify episodic groundwater recharge in arid regions which can be used within sustainable groundwater management frameworks to effectively manage groundwater resources.

  12. Investigation of Accelerated Partial Breast Patient Alignment and Treatment With Helical Tomotherapy Unit

    SciTech Connect

    Langen, Katja M. Buchholz, Daniel J.; Burch, Doug R. C.; Burkavage, Rob C.; Limaye, Arti U.; Meeks, Sanford L.; Kupelian, Patrick A.; Ruchala, Kenneth J.; Haimerl, Jason; Henderson, Doug; Olivera, Gustavo H.

    2008-03-15

    Purpose: To determine the precision of megavoltage computed tomography (MVCT)-based alignment of the seroma cavity for patients undergoing partial breast irradiation; and to determine whether accelerated partial breast irradiation (APBI) plans can be generated for TomoTherapy deliveries that meet the National Surgical Adjuvant Breast and Bowel Project (NSABP) B-39/Radiation Therapy Oncology Group (RTOG) 0413 protocol guidelines for target coverage and normal tissue dose limitations. Methods and Materials: We obtained 50 MVCT images from 10 patients. An interuser study was designed to assess the alignment precision. Using a standard helical and a fixed beam prototype ('topotherapy') optimizer, two APBI plans for each patient were developed. Results: The precision of the MVCT-based seroma cavity alignment was better than 2 mm if averaged over the patient population. Both treatment techniques could be used to generate acceptable APBI plans for patients that fulfilled the recommended NSABP B-39/RTOG-0413 selection criteria. For plans of comparable treatment time, the conformation of the prescription dose to the target was greater for helical deliveries, while the ipsilateral lung dose was significantly reduced for the topotherapy plans. Conclusions: The inherent volumetric imaging capabilities of a TomoTherapy Hi-Art unit allow for alignment of patients undergoing partial breast irradiation that is determined from the visibility of the seroma cavity on the MVCT image. The precision of the MVCT-based alignment was better than 2 mm ({+-} standard deviation) when averaged over the patient population. Using the NSABP B-39/RTOG-0413 guidelines, acceptable APBI treatment plans can be generated using helical- or topotherapy-based delivery techniques.

  13. A Hydrostratigraphic Model and Alternatives for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 97: Yucca Flat-Climax Mine, Lincoln and Nye Counties, Nevada

    SciTech Connect

    Geotechnical Sciences Group Bechtel Nevada

    2006-01-01

    A new three-dimensional hydrostratigraphic framework model for the Yucca Flat-Climax Mine Corrective Action Unit was completed in 2005. The model area includes Yucca Flat and Climax Mine, former nuclear testing areas at the Nevada Test Site, and proximal areas. The model area is approximately 1,250 square kilometers in size and is geologically complex. Yucca Flat is a topographically closed basin typical of many valleys in the Basin and Range province. Faulted and tilted blocks of Tertiary-age volcanic rocks and underlying Proterozoic and Paleozoic sedimentary rocks form low ranges around the structural basin. During the Cretaceous Period a granitic intrusive was emplaced at the north end of Yucca Flat. A diverse set of geological and geophysical data collected over the past 50 years was used to develop a structural model and hydrostratigraphic system for the basin. These were integrated using EarthVision? software to develop the 3-dimensional hydrostratigraphic framework model. Fifty-six stratigraphic units in the model area were grouped into 25 hydrostratigraphic units based on each unit's propensity toward aquifer or aquitard characteristics. The authors organized the alluvial section into 3 hydrostratigraphic units including 2 aquifers and 1 confining unit. The volcanic units in the model area are organized into 13 hydrostratigraphic units that include 8 aquifers and 5 confining units. The underlying pre-Tertiary rocks are divided into 7 hydrostratigraphic units, including 3 aquifers and 4 confining units. Other units include 1 Tertiary-age sedimentary confining unit and 1 Mesozoic-age granitic confining unit. The model depicts the thickness, extent, and geometric relationships of these hydrostratigraphic units (''layers'' in the model) along with the major structural features (i.e., faults). The model incorporates 178 high-angle normal faults of Tertiary age and 2 low-angle thrust faults of Mesozoic age. The complexity of the model area and the non

  14. Groundwater quality in the South Coast Interior Basins, California

    USGS Publications Warehouse

    Parsons, Mary C.; Belitz, Kenneth

    2014-01-01

    Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s untreated groundwater quality and increases public access to groundwater-quality information. The South Coast Interior Basins constitute one of the study units being evaluated.

  15. Treatment of ventilator-associated pneumonia and ventilator-associated tracheobronchitis in the intensive care unit

    PubMed Central

    Al-Omari, Awad; Mohammed, Masood; Alhazzani, Waleed; Al-Dorzi, Hasan M.; Belal, Mohammed S.; Albshabshe, Ali O.; Al-Subaie, Maha F.; Arabi, Yaseen M.

    2015-01-01

    Objectives: To assess current practices of different healthcare providers for treating extensively drug-resistant (XDR) Acinetobacter baumannii (AB) infections in tertiary-care centers in Saudi Arabia. Methods: This cross-sectional study was performed in tertiary-care centers of Saudi Arabia between March and June 2014. A questionnaire consisting of 3 parts (respondent characteristics; case scenarios on ventilator-associated pneumonia [VAP] and tracheobronchitis [VAT], and antibiotic choices in each scenario) was developed and sent electronically to participants in 34 centers across Saudi Arabia. Results: One-hundred and eighty-three respondents completed the survey. Most of the respondents (54.6%) preferred to use colistin-based combination therapy to treat VAP caused by XDR AB, and 62.8% chose to continue treatment for 2 weeks. Most of the participants (80%) chose to treat VAT caused by XDR AB with intravenous antibiotics. A significant percentage of intensive care unit (ICU) fellows (41.3%) and clinical pharmacists (35%) opted for 2 million units (mu) of colistin every 8 hours without a loading dose, whereas 60% of infectious disease consultants, 45.8% of ICU consultants, and 44.4% of infectious disease fellows preferred a 9 mu loading dose followed by 9 mu daily in divided doses. The responses for the scenarios were different among healthcare providers (p<0.0001). Conclusion: Most of the respondents in our survey preferred to use colistin-based combination therapy and intravenous antibiotics to treat VAP and VAT caused by XDR AB. However, colistin dose and duration varied among the healthcare providers. PMID:26620988

  16. Treatment of a sulfate-rich groundwater contaminated with perchloroethene in a hydroponic plant root mat filter and a horizontal subsurface flow constructed wetland at pilot-scale.

    PubMed

    Chen, Zhongbing; Kuschk, Peter; Paschke, Heidrun; Kästner, Matthias; Müller, Jochen A; Köser, Heinz

    2014-12-01

    A hydroponic plant root mat filter (HPRMF) was compared over 7months with a horizontal subsurface flow constructed wetland (HSSF CW) regarding the removal of perchloroethene (PCE) (about 2 mg L(-1)) from a sulfate- (850 mg L(-1)) and ammonia-rich (50 mg L(-1)) groundwater with a low TOC content. At a mean area specific inflow PCE load of 56 mg m(-2)d(-1), after 4m from inlet, the mean PCE removal during summer time reached 97% in the HPRMF and almost 100% in the HSSF CW. Within the first 2m in the HSSF CW metabolites like dichloroethenes, vinyl chloride and ethene accumulated, their concentrations decreased further along the flow path. Moreover, the tidal operation (a 7-d cycle) in the HSSFCW decreased the accumulation of PCE metabolites within the first 1m of the bed. The carcinogenic degradation metabolite vinyl chloride was not detected in the HPRMF. The smaller accumulation of the degradation metabolites in the HPRMF correlated with its higher redox potential. It can be concluded from this study that HPRMF appears an interesting alternative for special water treatment tasks and that tidal operation will show some positive effects on the removal of the accumulated PCE metabolites in HSSF CW. PMID:25025478

  17. Influence of perched groundwater on base flow

    USGS Publications Warehouse

    Niswonger, R.G.; Fogg, G.E.

    2008-01-01

    Analysis with a three-dimensional variably saturated groundwater flow model provides a basic understanding of the interplay between streams and perched groundwater. A simplified, layered model of heterogeneity was used to explore these relationships. Base flow contribution from perched groundwater was evaluated with regard to varying hydrogeologic conditions, including the size and location of the fine-sediment unit and the hydraulic conductivity of the fine-sediment unit and surrounding coarser sediment. Simulated base flow was sustained by perched groundwater with a maximum monthly discharge in excess of 15 L/s (0.6 feet3/s) over the length of the 2000-m stream reach. Generally, the rate of perched-groundwater discharge to the stream was proportional to the hydraulic conductivity of sediment surrounding the stream, whereas the duration of discharge was proportional to the hydraulic conductivity of the fine-sediment unit. Other aspects of the perched aquifer affected base flow, such as the depth of stream penetration and the size of the fine-sediment unit. Greater stream penetration decreased the maximum base flow contribution but increased the duration of contribution. Perched groundwater provided water for riparian vegetation at the demand rate but reduced the duration of perched-groundwater discharge n