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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. Recommended Amendment Mixture for in Situ Treatment of Water Management Unit Groundwater, Ashtabula Closure Project

    SciTech Connect

    DENHAM, MILES

    2004-05-12

    This document provides recommendations for the composition of a mixture of peat, hydroxyapatite, and sand to treat dissolved TCE, uranium, and technetium-99 in groundwater.One option for treatment was to remove the most contaminated soil and fill the engineered excavation with amendments for in situ clean up of the groundwater. A mixture of peat and hydroxyapatite will produce conditions necessary for stabilization of uranium and technetium-99, as well as anaerobic degradation of TCE. There is an ample body of literature supporting the use of peat to maintain the methanogenic conditions required for reductive dechlorination of TCE. Likewise, peat has been used to remediate uranium in groundwater. Furthermore, reducing conditions that stabilize uranium will also stabilize technetium-99. Addition of hydroxyapatite, a natural phosphate mineral, will enhance stabilization of uranium by precipitation of low solubility phosphate phases. Hydroxyapatite will also provide phosphate, a critical nutrient, to promote microbial degradation of the peat required to maintain methanogenic conditions. This is based on the composition of WMU groundwater, the groundwater flow rate, and an assumed 30-year lifetime for the outermost meter of the treatment zone. The lifetime of the treatment system as a whole depends on the size of the treatment zone. It is recommended that laboratory treatability studies be conducted prior to any implementation of this system. The studies should focus on effectiveness and longevity. Two specific issues that may affect these are replacement of hydroxyapatite by fluorapatite and precipitation of calcite within the system.

  3. 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.

  4. 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.

  5. Brackish groundwater in the United States

    USGS Publications Warehouse

    Stanton, Jennifer S.; Anning, David W.; Brown, Craig J.; Moore, Richard B.; McGuire, Virginia L.; Qi, Sharon L.; Harris, Alta C.; Dennehy, Kevin F.; McMahon, Peter B.; Degnan, James R.; Böhlke, John Karl

    2017-04-05

    For some parts of the Nation, large-scale development of groundwater has caused decreases in the amount of groundwater that is present in aquifer storage and that discharges to surface-water bodies. Water supply in some areas, particularly in arid and semiarid regions, is not adequate to meet demand, and severe drought is affecting large parts of the United States. Future water demand is projected to heighten the current stress on groundwater resources. This combination of factors has led to concerns about the availability of freshwater to meet domestic, agricultural, industrial, mining, and environmental needs. To ensure the water security of the Nation, currently [2016] untapped water sources may need to be developed.Brackish groundwater is an unconventional water source that may offer a partial solution to current and future water demands. In support of the national census of water resources, the U.S. Geological Survey completed the national brackish groundwater assessment to better understand the occurrence and characteristics of brackish groundwater in the United States as a potential water resource. Analyses completed as part of this assessment relied on previously collected data from multiple sources; no new data were collected. Compiled data included readily available information about groundwater chemistry, horizontal and vertical extents and hydrogeologic characteristics of principal aquifers (regionally extensive aquifers or aquifer systems that have the potential to be used as a source of potable water), and groundwater use. Although these data were obtained from a wide variety of sources, the compiled data are biased toward shallow and fresh groundwater resources; data representing groundwater that is at great depths and is saline were not as readily available.One of the most important contributions of this assessment is the creation of a database containing chemical characteristics and aquifer information for the known areas with brackish groundwater

  6. 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.

  7. Reengineering water treatment units for removal of Sr-90, I-129, Tc-99, and uranium from contaminated groundwater at the DOE's Savannah River Site

    SciTech Connect

    Serkiz, S.M.

    2000-02-09

    The 33 years of active operation of the F- and H-Area Seepage Basins to dispose of liquid low-level radioactive waste at the Department of Energy's Savannah River Site has resulted in the contamination of the groundwater underlying these basins with a wide variety of radionuclides and stable metals. The current Resource Conservation and Recovery Act (RCRA) Part B permit requires the operation of a pump-and-treat system capable of (1) maintaining hydraulic control of a specified contaminated groundwater plume, (2) treatment of the extracted groundwater, and (3) reinjection of the treated water hydraulically upgradient of the basins. Two multimillion-dollar water treatment units (WTUs) were designed and built in 1997 and the basic design consists of (1) reverse osmosis concentration, (2) chemical addition, neutralization, precipitation, polymer addition, flocculation, and clarification of the reverse osmosis concentrate, and (3) final polishing of the clarified water by ion exchange (IX) and sorption. During startup of these units numerous process optimizations were identified and, therefore, the WTUs have been recently reengineered. A systematic approach of: (1) developing a technical baseline through laboratory studies, (2) scale-up and plant testing, (3) plant modification, and (4) system performance monitoring was the basis for reengineering the WTUs. Laboratory experiments were conducted in order to establish a technical baseline for further scale-up/plant testing and system modifications. These studies focused on the following three areas of the process: (1) contaminant removal during chemical addition, neutralization and precipitation, (2) solids separation by flocculation, coagulation, clarification, and filtration, and (3) contaminant polishing of the clarified liquid by IX/sorption. Using standard laboratory-scale jar tests, the influences of pH and Fe concentration on contaminant removal during precipitation/neutralization were evaluated. The results of

  8. 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.

  9. 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.

  10. Malaria Treatment (United States)

    MedlinePlus

    ... a CDC Malaria Branch clinician. malaria@cdc.gov Malaria Treatment (United States) Recommend on Facebook Tweet Share Compartir Treatment of Malaria: Guidelines For Clinicians (United States) Download PDF version ...

  11. Potential corrosivity of untreated groundwater in the United States

    USGS Publications Warehouse

    Belitz, Kenneth; Jurgens, Bryant C.; Johnson, Tyler D.

    2016-07-12

    Corrosive groundwater, if untreated, can dissolve lead and other metals from pipes and other components in water distribution systems. Two indicators of potential corrosivity—the Langelier Saturation Index (LSI) and the Potential to Promote Galvanic Corrosion (PPGC)—were used to identify which areas in the United States might be more susceptible to elevated concentrations of metals in household drinking water and which areas might be less susceptible. On the basis of the LSI, about one-third of the samples collected from about 21,000 groundwater sites are classified as potentially corrosive. On the basis of the PPGC, about two-thirds of the samples collected from about 27,000 groundwater sites are classified as moderate PPGC, and about one-tenth as high PPGC. Potentially corrosive groundwater occurs in all 50 states and the District of Columbia.National maps have been prepared to identify the occurrence of potentially corrosive groundwater in the 50 states and the District of Columbia. Eleven states and the District of Columbia were classified as having a very high prevalence of potentially corrosive groundwater, 14 states as having a high prevalence of potentially corrosive groundwater, 19 states as having a moderate prevalence of potentially corrosive groundwater, and 6 states as having a low prevalence of potentially corrosive groundwater. These findings have the greatest implication for people dependent on untreated groundwater for drinking water, such as the 44 million people that are self-supplied and depend on domestic wells or springs for their water supply.

  12. 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.

  13. Agricultural Groundwater Demands in the Conterminous United States

    NASA Astrophysics Data System (ADS)

    Ho, M. W.; Parthasarathy, V.; Etienne, E.; Russo, T. A.; Devineni, N.; Lall, U.

    2016-12-01

    In the conterminous United States (CONUS), over 40% of water consumed for irrigation, livestock and domestic water is sourced from groundwater. The late 20th century and 21st century saw an expansion in irrigated agriculture across the CONUS that was accompanied by increased pumping of groundwater. Groundwater is typically used to mitigate impacts of drought on surface water supplies enabling water demands to be met as well as to augment sparse surface water resources in arid regions or where surface water availability is highly variable temporally and/or spatially. A Demand Sensitive Drought Index (DSDI) is used to examine the impacts of agricultural water needs on groundwater in the CONUS. The DSDI accounts for agricultural water deficits driven by low precipitation, high agricultural water demand, or a combination of both. Changes in groundwater levels relative to agricultural water deficits are characterized relative to precipitation during the growing season and winter precipitation. In several key irrigated agricultural regions in the CONUS, long-term trends in groundwater levels appear to reflect prolonged periods of surface water deficits resulting from land use and associated unsustainable water demands. These areas are subsequent unable to recover from persistent states of agricultural drought. Conversely, reductions in agricultural water demands for crops do not necessarily lead to immediate recovery of groundwater levels due to the demand for groundwater in other sectors. Calls to establish or reform groundwater policies have recently been made in an effort to achieve holistic groundwater management strategies that consider the human demands on both surface water and groundwater. There is a need for relevant groundwater policies to ensure that water demands are adequately managed across sectors without unsustainably depleting groundwater resources and to ensure efficient economic activity.

  14. 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)

  15. Baseline groundwater model update for p-area groundwater operable unit, NBN

    SciTech Connect

    Ross, J.; Amidon, M.

    2015-09-01

    This report documents the development of a numerical groundwater flow and transport model of the hydrogeologic system of the P-Area Reactor Groundwater Operable Unit at the Savannah River Site (SRS) (Figure 1-1). The P-Area model provides a tool to aid in understanding the hydrologic and geochemical processes that control the development and migration of the current tritium, tetrachloroethene (PCE), and trichloroethene (TCE) plumes in this region.

  16. 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.

  17. 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.

  18. Basewide Groundwater Operable Unit. Groundwater Operable Unit Remedial Investigation/Feasibility Study Report. Volume 1

    DTIC Science & Technology

    1994-06-01

    groundwater contamination at McClellan AFB is character- ized by small areas (* hot spots") with elevated concentrations or non- aqueous phase liquids (NAPL... hot spots, will achieve the remedial response objectives. The volume of contaminated groundwater would be reduced over time when hot spots are isolated...Innovative technologies, such as in situ bioremediation processes, could be applied once hot spots are isolated. Since groundwater would already be

  19. The importance of shallow confining units to submarine groundwater flow

    USGS Publications Warehouse

    Bratton, J.F.

    2007-01-01

    In addition to variable density flow, the lateral and vertical heterogeneity of submarine sediments creates important controls on coastal aquifer systems. Submarine confining units produce semi-confined offshore aquifers that are recharged on shore. These low-permeability deposits are usually either late Pleistocene to Holocene in age, or date to the period of the last interglacial highstand. Extensive confining units consisting of peat form in tropical mangrove swamps, and in salt marshes and freshwater marshes and swamps at mid-latitudes. At higher latitudes, fine-grained glaciomarine sediments are widespread. The net effect of these shallow confining units is that groundwater from land often flows farther offshore before discharging than would normally be expected. In many settings, the presence of such confining units is critical to determining how and where pollutants from land will be discharged into coastal waters. Alternatively, these confining units may also protect fresh groundwater supplies from saltwater intrusion into coastal wells.

  20. 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.

  1. Explanation of significant differences for the TNX groundwater operable unit

    SciTech Connect

    Palmer, E.R.

    1997-09-22

    This Explanation of Significant Differences (ESD) is being issued by the Department of Energy (DOE), the lead agency for the Savannah River Site (SRS), with concurrence by the Environmental Protection Agency-Region IV (EPA) and South Carolina Department of Health and Environmental Control (SCDHEC) to announce changes in the interim remediation strategy selected for the TNX Groundwater Operable Unit. The TNX Area is located adjacent to the Savannah River in the southwestern portion of SRS. The remedy selected in the Interim Record of Decision (IROD) to achieve the interim action goals was the Hybrid Groundwater Corrective Action (HGCA). The HGCA consisted of a recirculation well system and an air stripper with a series of groundwater extraction wells. The original remediation strategy needs to be modified because the recirculation well system was determined to be ineffective in this area due to geological factors and the nature of the contamination.

  2. Progress Toward Cleanup of Operable Unit 1 Groundwater at the US DOE Mound, Ohio, Site: Success of a Phase-Combined Remedy – 15310

    SciTech Connect

    Hooten, Gwendolyn; Cato, Rebecca; Looney, Brian; Huntsman, Brent

    2015-03-01

    Operable Unit 1 (OU-1) soil and groundwater have been affected by volatile organic compounds (VOC) Present groundwater remedy is collection, treatment, and disposal (pump and treat [P&T]) Several combinations of technologies were used to address soil and groundwater contamination Monitored natural attenuation (MNA) is a viable alternative Majority of source term has been excavated VOC concentrations in groundwater have decreased Attenuation mechanisms have been observed in the subsurface at OU-1

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. 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.

  8. Long-term groundwater depletion in the United States

    USGS Publications Warehouse

    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.

  9. 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.

  10. U1/U2 crib groundwater biological treatment demonstration project

    SciTech Connect

    Koegler, S.S.; Brouns, T.M.; Heath, W.O.

    1989-11-01

    The primary objective of the biological treatment project is to develop and demonstrate a process for Hanford groundwater remediation. Biodenitrification using facultative anaerobic microorganisms is a promising technology for the simultaneous removal of nitrates and organics from contaminated aqueous streams. During FY 1988, a consortium of Hanford groundwater microorganisms was shown to degrade both nitrates and carbon tetrachloride (CC1{sub 4}). A pilot-scale treatment system was designed and constructed based on the results of laboratory-and-bench-scale testing. This report summarizes the results of biological groundwater treatment studies performed during FY 1989 at the pilot-scale. These tests were conducted using a simulated Hanford groundwater with a continuous stirred-tank bioreactor, and a fluidized-bed bioreactor that was added to the pilot-scale treatment system in FY 1989. The pilot-scale system demonstrated continuous degradation of nitrates and CC1{sub 4} in a simulated groundwater. 4 refs., 7 figs., 1 tab.

  11. 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.

  12. 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.

  13. Current state of the art installation techniques for in-situ reactive wall groundwater treatment systems

    SciTech Connect

    Andromalos, K.B.; Jasperse, B.H.; Schindler, R.M.

    1999-07-01

    The consideration and use of in-situ reactive wall groundwater treatment systems on remediation projects continues to gain acceptance. Such systems are attractive due to their low initial capital costs and their minimal operation and maintenance costs compared to traditional pump and treat systems. These systems often are used as a polishing step to groundwater treatment in conjunction with source removal and natural attenuation. In constructing reactive wall groundwater treatment systems, various specialty construction techniques have been utilized. These techniques have included: deep soil mixing, bio-polymer trenching and slurry walls to successfully build funnel and gate systems with replaceable treatment cartridges as well as permeable treatment walls containing iron filings. Such systems have been installed in full-scale and pilot scale applications for various private companies, the Department of Energy and the United States Air Force and others. Several case histories are presented to illustrate these various installation techniques and their applications.

  14. Groundwater quality in the Upper Santa Ana Watershed study unit, California

    USGS Publications Warehouse

    Kent, Robert; 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 Upper Santa Ana Watershed is one of the study units being evaluated.

  15. Proven Alternatives for Aboveground Treatment of Arsenic in Groundwater

    EPA Pesticide Factsheets

    This issue paper, developed for EPA's Engineering Forum, identifies and summarizes experiences with proven aboveground treatment alternatives for arsenic in groundwater, and provides information on their relative effectiveness and cost.

  16. 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.

  17. 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)

  18. 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)

  19. 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.

  20. Superfund record of decision (EPA Region 4): Robins Air Force Base, Zone 1, operable unit 3, Groundwater, Warner Robins, Houston County, GA, September 25, 1995

    SciTech Connect

    1996-03-01

    This Interim Action Record of Decision (IROD) presents the selected interim remedial action for Operable Unit 3 of the Zone 1 Robins Air Force Base (AFB) Site. The selected interim remedy for Operable Unit 3, groundwater, includes: extraction of groundwater from at least two wells at the toe of Landfill No. 4.; Treatment of the extracted groundwater in a new treatment system that can meet standards for discharge to the Ocmulgee River; and discharge of the treated effluent to the Ocmulgee River under a revised National Pollutant Discharge Elimination.

  1. Development of a biological treatment system for Hanford groundwater remediation

    SciTech Connect

    Brouns, T.M.; Koegler, S.S.; Heath, W.O.; Fredrickson, J.K. ); Stensel, H.D. ); Johnstone, D.L. ); Donaldson, T.L. )

    1990-04-01

    The primary objective of the biological treatment program is to develop and demonstrate a biological process for Hanford groundwater remediation that is capable of nitrate (NO {sub 3}{sup {minus}}) and organic contaminant destruction. Biodenitrification using facultative anaerobic microorganisms is a promising technology for the simultaneous removal of NO{sub 3}{sup {minus}} and organics from contaminated aqueous streams. During FY 1989, microbial consortium from the Hanford groundwater was shown to degrade both NO{sub 3}{sup {minus}} and carbon tetrachloride (CC1{sub 4}). A pilot-scale treatment system was subsequently designed and constructed based on the results of laboratory- and bench-scale testing. The pilot-scale system demonstrated continuous degradation of NO{sub 3}{sup {minus}} and CC1{sub 4} in a simulated groundwater. This report summarizes the results of biological groundwater treatment studies performed during FY 1989 at the pilot-, laboratory-, and bench-scales. Pilot-scale test were conducted using a simulate Hanford groundwater with a continuous stirred-tank bioreactor (CSTR) and a fluidized-bed bioreactor that was added to the pilot-scale treatment system in FY 1989. Laboratory test focused on the degradation of CC1{sub 4} and on the microbial toxicity from CC1{sub 4}, hexavalent chromium (Cr{plus} {sup 6}), and cyanide (CN){sup {minus}} 15 refs., 18 figs., 1 tab.

  2. 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

  3. Monticello Mill Tailings Site, Operable Unit lll, Annual Groundwater Report, May 2015 Through April 2016

    SciTech Connect

    Nguyen, Jason; Smith, Fred

    2016-10-01

    This report provides the annual analysis of water quality restoration progress, cumulative through April 2016, for Operable Unit (OU) III, surface water and groundwater, of the U.S. Department of Energy (DOE) Office of Legacy Management (LM) Monticello Mill Tailings Site (MMTS). The MMTS is a Comprehensive Environmental Response, Compensation, and Liability Act National Priorities List site located in and near the city of Monticello, San Juan County, Utah. MMTS comprises the 110-acre site of a former uranium- and vanadium-ore-processing mill (mill site) and 1700 acres of surrounding private and municipal property. Milling operations generated 2.5 million cubic yards of waste (tailings) from 1942 to 1960. The tailings were impounded at four locations on the mill site. Inorganic constituents in the tailings drained from the impoundments to contaminate local surface water (Montezuma Creek) and groundwater in the underlying alluvial aquifer. Mill tailings dispersed by wind and water also contaminated properties surrounding and downstream of the mill site. Remedial actions to remove and isolate radiologically contaminated soil, sediment, and debris from the former mill site, Operable Unit I (OU I), and surrounding properties (OU II) were completed in 1999 with the encapsulation of the wastes in an engineered repository located on DOE property 1 mile south of the former mill site. This effectively removed the primary source of groundwater contamination; however, contamination of groundwater and surface water remains within OU III at levels that exceed water quality protection standards. Uranium is the primary contaminant of concern (COC). LM implemented monitored natural attenuation with institutional controls as the OU III remedy in 2004. Because groundwater restoration proceeded more slowly than expected and did not meet performance criteria established in the OU III Record of Decision (June 2004), LM implemented a contingency action in 2009 by an Explanation of

  4. 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.

  5. 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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. 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...

  7. 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.

  8. 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.

  9. 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)

  10. Biobarriers for groundwater treatment: a review.

    PubMed

    Careghini, A; Saponaro, S; Sezenna, E

    2013-01-01

    Biobarriers (BBs) are a new type of in situ technology for the remediation of contaminated groundwater. In recent years, this remediation technique has been more and more used in place of traditional Pump & Treat systems or other in situ technologies both in the USA and Europe. This work reviews the main experiences of BBs. The literature contains reports about tests and application at different scales (laboratory, pilot and full scale), which have been analyzed according to the aim of the study, the operative conditions adopted, the filling material, the inoculation procedure, the electron acceptor and the nutrient delivery systems. Operative conditions were extremely varied. Lab scale experiments pointed out good results in terms of pollutant removal efficiency. Pilot scale tests and full-scale applications confirmed the results obtained at lab scale, but also pointed out the importance of design for a proficient remediation system. The experiences underlined some possible critical issues: (a) the filling material must ensure proper hydraulic properties, but it also must be capable of keeping biomass in the reactive zone; (b) inoculation is a critical step and measurements should be carried out to check the initial distribution of microorganisms and its evolution over time; (c) electron acceptor and nutrient supply is usually required, but oxygenation into anaerobic aquifers can be critical.

  11. 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.

  12. 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.

  13. Regional groundwater characteristics and hydraulic conductivity based on geological units in Korean peninsula

    NASA Astrophysics Data System (ADS)

    Kim, Y.; Suk, H.

    2011-12-01

    In this study, about 2,000 deep observation wells, stream and/or river distribution, and river's density were analyzed to identify regional groundwater flow trend, based on the regional groundwater survey of four major river watersheds including Geum river, Han river, Youngsan-Seomjin river, and Nakdong river in Korea. Hydrogeologial data were collected to analyze regional groundwater flow characteristics according to geological units. Additionally, hydrological soil type data were collected to estimate direct runoff through SCS-CN method. Temperature and precipitation data were used to quantify infiltration rate. The temperature and precipitation data were also used to quantify evaporation by Thornthwaite method and to evaluate groundwater recharge, respectively. Understanding the regional groundwater characteristics requires the database of groundwater flow parameters, but most hydrogeological data include limited information such as groundwater level and well configuration. In this study, therefore, groundwater flow parameters such as hydraulic conductivities or transmissivities were estimated using observed groundwater level by inverse model, namely PEST (Non-linear Parameter ESTimation). Since groundwater modeling studies have some uncertainties in data collection, conceptualization, and model results, model calibration should be performed. The calibration may be manually performed by changing parameters step by step, or various parameters are simultaneously changed by automatic procedure using PEST program. In this study, both manual and automatic procedures were employed to calibrate and estimate hydraulic parameter distributions. In summary, regional groundwater survey data obtained from four major river watersheds and various data of hydrology, meteorology, geology, soil, and topography in Korea were used to estimate hydraulic conductivities using PEST program. Especially, in order to estimate hydraulic conductivity effectively, it is important to perform

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Groundwater

    USGS Publications Warehouse

    Stonestrom, David A.; Wohl, Ellen E.

    2016-01-01

    Groundwater represents the terrestrial subsurface component of the hydrologic cycle. As such, groundwater is generally in motion, moving from elevated areas of recharge to lower areas of discharge. Groundwater usually moves in accordance with Darcy’s law (Dalmont, Paris: Les Fontaines Publiques de la Ville de Dijon, 1856). Groundwater residence times can be under a day in small upland catchments to over a million years in subcontinental-sized desert basins. The broadest definition of groundwater includes water in the unsaturated zone, considered briefly here. Water chemically bound to minerals, as in gypsum (CaSO4 • 2H2O) or hydrated clays, cannot flow in response to gradients in total hydraulic head (pressure head plus elevation head); such water is thus usually excluded from consideration as groundwater. In 1940, M. King Hubbert showed Darcy’s law to be a special case of thermodynamically based potential field equations governing fluid motion, thereby establishing groundwater hydraulics as a rigorous engineering science (Journal of Geology 48, pp. 785–944). The development of computer-enabled numerical methods for solving the field equations with real-world approximating geometries and boundary conditions in the mid-1960s ushered in the era of digital groundwater modeling. An estimated 30 percent of global fresh water is groundwater, compared to 0.3 percent that is surface water, 0.04 percent atmospheric water, and 70 percent that exists as ice, including permafrost (Shiklomanov and Rodda 2004, cited under Groundwater Occurrence). Groundwater thus constitutes the vast majority—over 98 percent—of the unfrozen fresh-water resources of the planet, excluding surface-water reservoirs. Environmental dimensions of groundwater are equally large, receiving attention on multiple disciplinary fronts. Riparian, streambed, and spring-pool habitats can be sensitively dependent on the amount and quality of groundwater inputs that modulate temperature and solutes

  20. Groundwater quality in the Western San Joaquin Valley study unit, 2010: California GAMA Priority Basin Project

    USGS Publications Warehouse

    Fram, Miranda S.

    2017-06-09

    Water quality in groundwater resources used for public drinking-water supply in the Western San Joaquin Valley (WSJV) was investigated by the USGS in cooperation with the California State Water Resources Control Board (SWRCB) as part of its Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project. The WSJV includes two study areas: the Delta–Mendota and Westside subbasins of the San Joaquin Valley groundwater basin. Study objectives for the WSJV study unit included two assessment types: (1) a status assessment yielding quantitative estimates of the current (2010) status of groundwater quality in the groundwater resources used for public drinking water, and (2) an evaluation of natural and anthropogenic factors that could be affecting the groundwater quality. The assessments characterized the quality of untreated groundwater, not the quality of treated drinking water delivered to consumers by water distributors.The status assessment was based on data collected from 43 wells sampled by the U.S. Geological Survey for the GAMA Priority Basin Project (USGS-GAMA) in 2010 and data compiled in the SWRCB Division of Drinking Water (SWRCB-DDW) database for 74 additional public-supply wells sampled for regulatory compliance purposes between 2007 and 2010. To provide context, concentrations of constituents measured in groundwater were compared to U.S. Environmental Protection Agency (EPA) and SWRCB-DDW regulatory and non-regulatory benchmarks for drinking-water quality. The status assessment used a spatially weighted, grid-based method to estimate the proportion of the groundwater resources used for public drinking water that has concentrations for particular constituents or class of constituents approaching or above benchmark concentrations. This method provides statistically unbiased results at the study-area scale within the WSJV study unit, and permits comparison of the two study areas to other areas assessed by the GAMA Priority Basin Project

  1. Mineralization of the Common Groundwater Pollutant 2,6-Dichlorobenzamide (BAM) and its Metabolite 2,6-Dichlorobenzoic Acid (2,6-DCBA) in Sand Filter Units of Drinking Water Treatment Plants.

    PubMed

    Vandermaesen, Johanna; Horemans, Benjamin; Degryse, Julie; Boonen, Jos; Walravens, Eddy; Springael, Dirk

    2016-09-20

    The intrinsic capacity to mineralize the groundwater pollutant 2,6-dichlorobenzamide (BAM) and its metabolite 2,6-dichlorobenzoic acid (2,6-DCBA) was evaluated in samples from sand filters (SFs) of drinking water treatment plants (DWTPs). Whereas BAM mineralization occurred rarely and only in SFs exposed to BAM, 2,6-DCBA mineralization was common in SFs, including those treating uncontaminated water. Nevertheless, SFs treating BAM contaminated water showed the highest 2,6-DCBA mineralization rates. For comparison, 2,6-DCBA and BAM mineralization were determined in various topsoil samples. As in SF samples, BAM mineralization was rare, whereas 2,6-DCBA mineralization capacity appeared widespread, with high mineralization rates found especially in forest soils. Multivariate analysis showed that in both SF and soil samples, high 2,6-DCBA mineralization correlated with high organic carbon content. Adding a 2,6-DCBA degradation deficient mutant of the BAM mineralizing Aminobacter sp. MSH1 confirmed that 2,6-DCBA produced from BAM is rapidly mineralized by the endogenous microbial community in SFs showing intrinsic 2,6-DCBA mineralization. This study demonstrates that (i) 2,6-DCBA mineralization is widely established in SFs of DWTPs, allowing the mineralization of 2,6-DCBA produced during BAM degradation and (ii) the first metabolic step in BAM mineralization is rare in microbial communities, rather than its further degradation beyond 2,6-DCBA.

  2. 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.

  3. 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.

  4. 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.

  5. Soda ash treatment of a strontium-90-contaminated groundwater seep

    SciTech Connect

    Spalding, B.P.; Munro, I.I.

    1983-01-01

    A /sup 90/Sr-contaminated groundwater seep on the perimeter of a low-level radioactive solid waste disposal area at the Oak Ridge National Laboratory (ORNL) was treated by burying 315 kg of soda ash in the groundwater flow path leading to the seep, and placing 45 kg of soda ash on the surface of the seep. The concentration of /sup 90/Sr in the seep water fell from an average of 7000 Bq L/sup -1/ to 900 Bq L/sup -1/ for the 90 d after burial, followed by a period of gradual rise back to pretreatment levels over the next 100 d. The electrical conductivity and pH of the seep water increased following soda ash burial, while water hardness fell. Hardness was highly correlated (r = 0.84) with /sup 90/Sr concentrations over the entire 2-year observation period, indicating the similar behavior of /sup 90/Sr and soluble Ca and Mg. This in situ softening of, and /sup 90/Sr precipitation from, the seep water was achieved by coprecipitation of /sup 90/Sr with Ca(Mg)CO/sub 3/ until the buried soda ash was depleted by dissolution in the groundwater. The soda ash treatment of groundwater seeps appears to be most practical as an interim technique for those situations requiring an immediate, but temporary, corrective action. During this limited but effective period, more permanent corrective actions could be planned at the source of contamination. The electrical conductivity, pH, and hardness of the larger surface stream, into which this seep discharges, were not affected by the soda ash burial, most likely due to the approximately 2000-fold dilution effected by this stream.

  6. Full scale biological treatment of heavy metal contaminated groundwater

    SciTech Connect

    Vegt, A.L. De; Buisman, C.J.N.

    1995-07-01

    Soil and groundwater beneath a zinc production plant in The Netherlands are contaminated with metals and sulfate. To avoid contamination of nearby drinking water aquifers, a hydro-geological containment system and a biological treatment plant for the extracted ground water have been installed. Currently about 5,000 M{sup 3}/day of groundwater is extracted from a combination of 12 shallow and deep wells. Heavy metals and sulfate have to be removed from the extracted water before it can be discharged into a river. Several water treatment methods have been studied and pilot tested at the site. The preferred and selected process is based on the activity of sulfate reducing bacteria (SRB) and combines sulfate removal and heavy metal removal in one single installation. Anaerobic bacteria reduce sulfate to sulfide resulting in the precipitation of metal sulfides. Excess sulfide is biologically converted to elemental sulfur. A full scale biological treatment system was started up in May 1992. Design, start-up, commissioning and operational experiences are reported in this paper. Concentrations of metals and sulfate in the SRB water treatment plant effluent are well within the limits set by the Dutch Authorities for discharge to surface water.

  7. Superfund record of decision (EPA Region 10): Wyckoff/Eagle Harbor Superfund Site, Groundwater Operable Unit, Bainbridge Island, WA, September 1994

    SciTech Connect

    Not Available

    1994-09-29

    The decision document presents the interim remedial action for the Wyckoff Groundwater Operable Unit, one of four operable units at the Wyckoff/Eagle Harbor Superfund site, located at Bainbridge Island, Kitsap County, Washington. The remedy selected in this interim Record of Decision addresses the need to contain contaminated groundwater and non-aqueous phase liquids (NAPL) to the immediate area of the wood treatment operations of the former Wyckoff facility and not allow it to migrate into Eagle Harbor or into deeper drinking water aquifers.

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. Ground-water data collected in the Missouri River Basin units in Kansas during 1949

    USGS Publications Warehouse

    Berry, Delmar W.

    1950-01-01

    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 the program for development of the resources of the basin by the U.S. Bureau of Reclamation and other Federal Agencies. The studies of the ground-water resources in the part of Kansas that lies within the Basin have been coordinated with the cooperative program of ground-water studies already being carried on in Kansas by the Federal Geological Survey and the State Geological Survey of Kansas with the cooperation of the Division of Sanitation of the Kansas State Board of Health and the Division of Water Resources of the Kansas State Board of Agriculture. Areas in which ground-water data have been collected under the Missouri Basin program include the Almena Unit in Norton and Phillips Counties; the Bostwick Unit in Jewell, Republic, and Cloud Counties; the Cedar Bluff Unit in Ellis, Rush, and Trego Counties; the Glen Elder Unit in Mitchell County; the Webster Unit in Osborne County; and the Wilson Unit in Lincoln County. Most of the ground-water data presented in this report were collected during 1949. Most of the data collected in these areas prior to the end of 1947 were presented in a report that was mimeographed in September 1948 and most of the data collected during 1948 were presented in a report that was mimeographed in November 1949. This report is the third of a series of annual reports on ground-water data collected in the Missouri Basin units in Kansas. These annual reports are a means of more promptly releasing for administrative use the data collected each year. Data that are included in the annual reports for a given area will be assembled later in a report on the geology and hydrology of that area. An index of the data collected and presented in the 1947, 1948, and 1949 reports is given in table 1.

  14. Evaluation of radon occurrence in groundwater from 16 geologic units in Pennsylvania, 1986–2015, with application to potential radon exposure from groundwater and indoor air

    USGS Publications Warehouse

    Gross, Eliza L.

    2017-05-11

    Results from 1,041 groundwater samples collected during 1986‒2015 from 16 geologic units in Pennsylvania, associated with 25 or more groundwater samples with concentrations of radon-222, were evaluated in an effort to identify variations in radon-222 activities or concentrations and to classify potential radon-222 exposure from groundwater and indoor air. Radon-222 is hereafter referred to as “radon.” Radon concentrations in groundwater greater than or equal to the proposed U.S. Environmental Protection Agency (EPA) maximum contaminant level (MCL) for public-water supply systems of 300 picocuries per liter (pCi/L) were present in about 87 percent of the water samples, whereas concentrations greater than or equal to the proposed alternative MCL (AMCL) for public water-supply systems of 4,000 pCi/L were present in 14 percent. The highest radon concentrations were measured in groundwater from the schists, gneisses, and quartzites of the Piedmont Physiographic Province.In this study, conducted by the U.S. Geological Survey in cooperation with the Pennsylvania Department of Health and the Pennsylvania Department of Environmental Protection, groundwater samples were aggregated among 16 geologic units in Pennsylvania to identify units with high median radon concentrations in groundwater. Graphical plots and statistical tests were used to determine variations in radon concentrations in groundwater and indoor air. Median radon concentrations in groundwater samples and median radon concentrations in indoor air samples within the 16 geologic units were classified according to proposed and recommended regulatory limits to explore potential radon exposure from groundwater and indoor air. All of the geologic units, except for the Allegheny (Pa) and Glenshaw (Pcg) Formations in the Appalachian Plateaus Physiographic Province, had median radon concentrations greater than the proposed EPA MCL of 300 pCi/L, and the Peters Creek Schist (Xpc), which is in the Piedmont

  15. 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

  16. Confining units as barriers to regional ground-water contamination: Hydrogeologic maps as planning tools

    SciTech Connect

    Pucci, A.A. Jr.

    1995-12-31

    Hydrogeologic maps are typical products of ground-water investigations. The features on these maps can be used by planning commissions to optimize land use. Planners could use confining-unit outcrop maps for siting landfills and hazardous material handling facilities. This paper examines ground-water chemistry from 53 wells, field measurements, hydrogeologic conditions from a quasi-3-D flow model for predevelopment (before 1900), and 1984 flow conditions, and evaluates relationships between them. Several recent reports have examined water quality in the area. The wells for this paper were screened in the Potomac-Raritan-Magothy aquifer system (PRMA) in the northern Coastal Plain of New Jersey in a 184 square mile area which is undergoing rapid growth. Hydrogeologic conditions considered include aquifer sampled, well location relative to flow-path distance from the outcrop, confining-unit thickness, and confining-unit vertical hydraulic conductivity (Kv). Visual, graphical and principal component analyses were used to evaluate the relationships.

  17. Ground-Water Recharge in the Arid and Semiarid Southwestern United States - Climatic and Geologic Framework

    USGS Publications Warehouse

    Stonestrom, David A.; Harrill, James R.

    2007-01-01

    Ground-water recharge in the arid and semiarid southwestern United States results from the complex interplay of climate, geology, and vegetation across widely ranging spatial and temporal scales. Present-day recharge tends to be narrowly focused in time and space. Widespread water-table declines accompanied agricultural development during the twentieth century, demonstrating that sustainable ground-water supplies are not guaranteed when part of the extracted resource represents paleorecharge. Climatic controls on ground-water recharge range from seasonal cycles of summer monsoonal and winter frontal storms to multimillennial cycles of glacial and interglacial periods. Precipitation patterns reflect global-scale interactions among the oceans, atmosphere, and continents. Large-scale climatic influences associated with El Ni?o and Pacific Decadal Oscillations strongly but irregularly control weather in the study area, so that year-to-year variations in precipitation and ground-water recharge are large and difficult to predict. Proxy data indicate geologically recent periods of multidecadal droughts unlike any in the modern instrumental record. Anthropogenically induced climate change likely will reduce ground-water recharge through diminished snowpack at higher elevations, and perhaps through increased drought. Future changes in El Ni?o and monsoonal patterns, both crucial to precipitation in the study area, are highly uncertain in current models. Land-use modifications influence ground-water recharge directly through vegetation, irrigation, and impermeable area, and indirectly through climate change. High ranges bounding the study area?the San Bernadino Mountains and Sierra Nevada to the west, and the Wasatch and southern Colorado Rocky Mountains to the east?provide external geologic controls on ground-water recharge. Internal geologic controls stem from tectonic processes that led to numerous, variably connected alluvial-filled basins, exposure of extensive

  18. 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.

  19. Linking teleconnection patterns to low periodicity groundwater level fluctuations across the United Kingdom

    NASA Astrophysics Data System (ADS)

    Holman, I.; Neulens, Q.

    2016-12-01

    We describe the most comprehensive assessment of the influence of large scale teleconnection patterns on groundwater levels in the United Kingdom to-date, looking at long records in boreholes from the Chalk (fractured), Sandstone (inter-granular) and limestone (fractured) aquifers. Singular Spectrum Analysis revealed that the annual cycle only explains <2 to 63% of the variance in the groundwater level time series, with a lower proportion in the inter-granular aquifers (< 2 to 40%, compared to 8-63% in the fractured aquifers). Wavelet Coherence analysis shows that the Arctic Oscillation, East Atlantic pattern and the North Atlantic Oscillation have an influence on groundwater levels at periods ranging from multiannual to multidecadal, with these effects being mostly consistent among boreholes across the different aquifers and parts of the country. The phase angle suggests a timelag of around 5 years for the effect of the NAO. Further analysis using Empirical Orthogonal Function analysis reveals the strong statistically signifencant influences of the East Atlantic pattern, North Atlantic Oscillation, Arctic Oscillation, and the Scandinavia pattern on winter precipitation in the UK. However, correlation between the North Atlantic Oscillation, Arctic Oscillation, and the Scandinavia pattern makes the causal link between individual teleconnection patterns and groundwater levels uncertain. Ongoing research aims to increase the spatial extent of the analysis and to better constrain the conceptual understanding of system memory in order to enable improved prediction and management of groundwater level response to extreme events (particularly droughts).

  20. Soil characteristics and agrichemicals in groundwater of the Midwestern United States

    USGS Publications Warehouse

    Burkart, M.; Kolpin, D.W.; Jaquis, R.J.; Cole, K.

    2001-01-01

    A comprehensive set of soil characteristics were examined to determine the effect of soil on the transport of agrichemicals to groundwater. This paper examines the relation of soil characteristics to concentrations and occurrence nitrate, atrazine, and atrazine residue from 99 wells completed in unconsolidated aquifers across the Midwestern United States. Soil characteristics that determine the rate of water movement were directly related to the occurrence and concentrations of nitrate and atrazine in groundwater. The substantial differences in the relations found among soil characteristics and nitrate and atrazine in groundwater suggest that different processes affect the transformation, adsorption, and transport of these contaminants. A multi-variable analysis determined that the soil characteristics examined explained the amount of variability in concentrations for nitrate (19%), atrazine (33%), and atrazine residue (29%). These results document that, although soils do affect the transport of agrichemicals to groundwater, other factors such as hydrology, land use, and climate must also be considered to understand the occurrence of agrichemicals in groundwater.

  1. Conceptual understanding and groundwater quality of selected basin-fill aquifers in the Southwestern United States

    USGS Publications Warehouse

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

    2010-01-01

    The National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey has been conducting a regional analysis of water quality in the principal aquifer systems in the southwestern United States (hereinafter, “Southwest”) since 2005. Part of the NAWQA Program, the objective of the Southwest Principal Aquifers (SWPA) study is to develop a better understanding of water quality in basin-fill aquifers in the region by synthesizing information from case studies of 15 basins into a common set of important natural and human-related factors found to affect groundwater quality.The synthesis consists of three major components:1. Summary of current knowledge about the groundwater systems, and the status of, changes in, and influential factors affecting quality of groundwater in basin-fill aquifers in 15 basins previously studied by NAWQA (this report).2. Development of a conceptual model of the primary natural and human-related factors commonly affecting groundwater quality, thereby building a regional understanding of the susceptibility and vulnerability of basin-fill aquifers to contaminants.3. Development of statistical models that relate the concentration or occurrence of specific chemical constituents in groundwater to natural and human-related factors linked to the susceptibility and vulnerability of basin-fill aquifers to contamination.Basin-fill aquifers occur in about 200,000 mi2 of the 410,000 mi2 SWPA study area and are the primary source of groundwater supply for cities and agricultural communities. Four of the principal aquifers or aquifer systems of the United States are included in the basin-fill aquifers of the study area: (1) the Basin and Range basin-fill aquifers in California, Nevada, Utah, and Arizona; (2) the Rio Grande aquifer system in New Mexico and Colorado; (3) the California Coastal Basin aquifers; and (4) the Central Valley aquifer system in California. Because of the generally limited availability of surface-water supplies in

  2. 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

  3. Long-term trends of ground-water levels in the United States

    USGS Publications Warehouse

    Fishel, V.C.

    1956-01-01

    Ground-water levels at the end of 1954 were at or near record-low stages throughout most of the southern two-thirds of the United States. These low stages, like those of the early 1930's, have led to frequent expression of the opinion that the water table throughout the country is continuously falling and that we are gradually exhausting our ground-water supplies. A good record of changes in ground-water levels is being obtained by the United States Geological Survey and cooperating State agencies from periodical measurements of water levels in nearly 20,000 observation wells. The records of some of these wells extend back 50 years. Many records are available for the period beginning in 1934. These long-term records indicate that in some areas the ground-water supply is overdeveloped. In the great majority of areas, however, the stage of the water levels correlates with the precipitation. Much of the country has been in drought and the water levels are at a low stage. As the precipitation increases, as it is bound to do later, the water levels will return to higher stages.

  4. 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.

  5. 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

  6. Trace elements and radon in groundwater across the United States, 1992-2003

    USGS Publications Warehouse

    Ayotte, Joseph D.; Gronberg, Jo Ann M.; Apodaca, Lori E.

    2011-01-01

    Trace-element concentrations in groundwater were evaluated for samples collected between 1992 and 2003 from aquifers across the United States as part of the U.S. Geological Survey National Water-Quality Assessment Program. This study describes the first comprehensive analysis of those data by assessing occurrence (concentrations above analytical reporting levels) and by comparing concentrations to human-health benchmarks (HHBs). Data from 5,183 monitoring and drinking-water wells representing more than 40 principal and other aquifers in humid and dry regions and in various land-use settings were used in the analysis. Trace elements measured include aluminum (Al), antimony (Sb), arsenic (As), barium (Ba), beryllium (Be), boron (B), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb), lithium (Li), manganese (Mn), molybdenum (Mo), nickel (Ni), selenium (Se), silver (Ag), strontium (Sr), thallium (Tl), uranium (U), vanadium (V), and zinc (Zn). Radon (Rn) gas also was measured and is included in the data analysis. Climate influenced the occurrence and distribution of trace elements in groundwater whereby more trace elements occurred and were found at greater concentrations in wells in drier regions of the United States than in humid regions. In particular, the concentrations of As, Ba, B, Cr, Cu, Mo, Ni, Se, Sr, U, V, and Zn were greater in the drier regions, where processes such as chemical evolution, ion complexation, evaporative concentration, and redox (oxidation-reduction) controls act to varying degrees to mobilize these elements. Al, Co, Fe, Pb, and Mn concentrations in groundwater were greater in humid regions of the United States than in dry regions, partly in response to lower groundwater pH and (or) more frequent anoxic conditions. In groundwater from humid regions, concentrations of Cu, Pb, Rn, and Zn were significantly greater in drinking-water wells than in monitoring wells. Samples from drinking-water wells in dry regions had

  7. 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.  

  8. [Groundwater].

    PubMed

    González De Posada, Francisco

    2012-01-01

    From the perspective of Hydrogeology, the concept and an introductory general typology of groundwater are established. From the perspective of Geotechnical Engineering works, the physical and mathematical equations of the hydraulics of permeable materials, which are implemented, by electric analogical simulation, to two unique cases of global importance, are considered: the bailing during the construction of the dry dock of the "new shipyard of the Bahia de Cádiz" and the waterproofing of the "Hatillo dam" in the Dominican Republic. From a physical fundamental perspective, the theories which are the subset of "analogical physical theories of Fourier type transport" are related, among which the one constituted by the laws of Adolf Fick in physiology occupies a historic role of some relevance. And finally, as a philosophical abstraction of so much useful mathematical process, the one which is called "the Galilean principle of the mathematical design of the Nature" is dealt with.

  9. 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.

  10. 1990 annual ground-water report K-1407-B and K-1407-C interim status units Oak Ridge K-25 Site

    SciTech Connect

    Not Available

    1991-02-01

    The Tennessee Department of Health and Environment (TDHE) Rules Governing Hazardous Waste Management require that specific ground-water information for interim status units be reported in conjunction with the annual hazardous waste treatment, storage, and disposal report (TN 1200-1-11-.05(6)(e)1 and 2). To be included in the report are, the data from annual/semiannual ground-water sampling, results of statistical analyses, and an evaluation of ground-water surface elevations for units in detection monitoring. Martin Marietta Energy Systems, Inc. manages the K-25 Site in Oak Ridge, Tennessee for the Department of Energy. Two interim status units at K-25 require ground-water monitoring, the K-1407-B and K-1407-C Holding Ponds. Both of these units were surface impoundments that have been drained and the waste sludges removed in response to the November 8, 1988, interim status closure milestone. The K-1407-C Pond was drained in mid-1987 and sludge removal activities were completed in November of 1988. The K-1407-B Pond was drained inOctober 1988, and sludge removal activities were completed in August of 1989. Both units have undergone soil sampling to verify complete sludge removal which would allow them to be ``clean closed`` under interim status regulations. Analytical results of soil samples from K-1407-C Pond are currently being evaluated and soil samples from K-1407-B Pond are undergoing laboratory analysis at this time. This report presents the results of the ground-water monitoring conducted at each unit in compliance with interim status regulations.

  11. 1990 annual ground-water report K-1407-B and K-1407-C interim status units Oak Ridge K-25 Site

    SciTech Connect

    Not Available

    1991-02-01

    The Tennessee Department of Health and Environment (TDHE) Rules Governing Hazardous Waste Management require that specific ground-water information for interim status units be reported in conjunction with the annual hazardous waste treatment, storage, and disposal report (TN 1200-1-11-.05(6)(e)1 and 2). To be included in the report are, the data from annual/semiannual ground-water sampling, results of statistical analyses, and an evaluation of ground-water surface elevations for units in detection monitoring. Martin Marietta Energy Systems, Inc. manages the K-25 Site in Oak Ridge, Tennessee for the Department of Energy. Two interim status units at K-25 require ground-water monitoring, the K-1407-B and K-1407-C Holding Ponds. Both of these units were surface impoundments that have been drained and the waste sludges removed in response to the November 8, 1988, interim status closure milestone. The K-1407-C Pond was drained in mid-1987 and sludge removal activities were completed in November of 1988. The K-1407-B Pond was drained inOctober 1988, and sludge removal activities were completed in August of 1989. Both units have undergone soil sampling to verify complete sludge removal which would allow them to be clean closed'' under interim status regulations. Analytical results of soil samples from K-1407-C Pond are currently being evaluated and soil samples from K-1407-B Pond are undergoing laboratory analysis at this time. This report presents the results of the ground-water monitoring conducted at each unit in compliance with interim status regulations.

  12. 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...

  13. Ground-Water Recharge in the Arid and Semiarid Southwestern United States

    USGS Publications Warehouse

    Stonestrom, David A.; Constantz, Jim; Ferre, Ty P.A.; Leake, Stanley A.

    2007-01-01

    Ground-water recharge in the arid and semiarid southwestern United States results from the complex interplay of climate, geology, and vegetation across widely ranging spatial and temporal scales. Present-day recharge tends to be narrowly focused in time and space. Widespread water-table declines accompanied agricultural development during the twentieth century, demonstrating that sustainable ground-water supplies are not guaranteed when part of the extracted resource represents paleorecharge. Climatic controls on ground-water recharge range from seasonal cycles of summer monsoonal and winter frontal storms to multimillennial cycles of glacial and interglacial periods. Precipitation patterns reflect global-scale interactions among the oceans, atmosphere, and continents. Large-scale climatic influences associated with El Ni?o and Pacific Decadal Oscillations strongly, but irregularly, control weather in the study area, so that year-to-year variations in precipitation and ground-water recharge are large and difficult to predict. Proxy data indicate geologically recent periods of naturally occurring multidecadal droughts unlike any in the modern instrumental record. Any anthropogenically induced climate change will likely reduce ground-water recharge through diminished snowpack at higher elevations. Future changes in El Ni?o and monsoonal patterns, both crucial to precipitation in the study area, are highly uncertain in current models. Current land-use modifications influence ground-water recharge through vegetation, irrigation, and impermeable area. High mountain ranges bounding the study area?the San Bernadino Mountains and Sierra Nevada to the west, and the Wasatch and southern Colorado Rocky Mountains to the east?provide external geologic controls on ground-water recharge. Internal geologic controls stem from tectonic processes that led to numerous, variably connected alluvial-filled basins, exposure of extensive Paleozoic aquifers in mountainous recharge areas

  14. Gravity Monitoring of Ground-Water Storage Change in the Southwestern United States

    NASA Astrophysics Data System (ADS)

    Winester, D.; Pool, D. R.; Schmerge, D. L.; Hoffmann, J. P.; Keller, G. R.

    2004-12-01

    Repeat measurements of absolute gravity have been made since 1998 to estimate changes in ground-water mass as part of ground-water budget estimates in arid and semiarid regions of the Southwestern United States. The absolute acceleration of gravity is measured twice each year at 16 stations to an accuracy of about plus or minus 2 microGal, or about 5 cm of water. Observations are normally done for the purpose of providing gravity control for relative gravity surveys of networks of stations across wider areas. Other data incorporated into the ground-water budget estimates include precipitation, water levels, moisture content in the unsaturated zone, surface water runoff, and ellipsoid heights using the Global Positioning System (GPS). Gravity and water-level changes are correlated for stations measured in the Basin and Range Physiographic Province near Tucson, Phoenix, Casa Grande, and Sierra Vista, Arizona. Decreasing gravity and water levels in the Tucson area since the summer of 1998 are likely related to predominant drought conditions and decreases in ground-water storage following above average winter precipitation and recharge during the El Nino of 1998. Increases in gravity at stations in the upper and middle Verde Valley Watershed in central Arizona since the fall of 2000 do not correlate well with declining streamflows and water levels and may be caused by temporary increases in soil moisture following wet winters. There have been no significant observed gravity changes at two stations in the El Paso, Texas, area since the initial observations during the summer of 2003, even though ground-water pumping in the area has been heavy.

  15. 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.

  16. 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.

  17. Distribution of Potentially Corrosive Groundwater in the United States: Implications for an Important Source of Drinking Supply

    NASA Astrophysics Data System (ADS)

    Belitz, K.; Jurgens, B. C.; Johnson, T. D.

    2016-12-01

    Corrosive groundwater, if untreated, can dissolve lead and other metals from pipes and other components in water distribution systems. Two indicators of potential corrosivity—the Langelier Saturation Index (LSI) and the Potential to Promote Galvanic Corrosion (PPGC)—were used to identify which areas in the United States might be more susceptible to elevated concentrations of metals in household drinking water and which areas might be less susceptible. On the basis of the LSI, about one-third of the samples collected from about 21,000 groundwater sites are classified as potentially corrosive. On the basis of the PPGC, about two-thirds of the samples collected from about 27,000 groundwater sites are classified as moderate PPGC, and about one-tenth as high PPGC. Potentially corrosive groundwater occurs in all 50 states and the District of Columbia. National maps have been prepared to identify the occurrence of potentially corrosive groundwater in the 50 states and the District of Columbia. Eleven states and the District of Columbia were classified as having a very high prevalence of potentially corrosive groundwater, 14 states as having a high prevalence of potentially corrosive groundwater, 19 states as having a moderate prevalence of potentially corrosive groundwater, and 6 states as having a low prevalence of potentially corrosive groundwater. These findings have the greatest implication for people dependent on untreated groundwater for drinking water, such as the 44 million people that are self-supplied and depend on domestic wells or springs for their water supply. Belitz, Kenneth, Jurgens, B.C., and Johnson, T.D., 2016, Potential corrosivity of untreated groundwater in the United States: U.S. Geological Survey Scientific Investigations Report 2016-5092, 16 p., http://dx.doi.org/10.3133/sir20165092.

  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. 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...

  3. 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...

  4. 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

  5. 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...

  6. 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...

  7. An Effect Analysis of Comprehensive Treatment of Groundwater Over-Exploitation in Cheng'an County, Hebei Province, China.

    PubMed

    Shao, Weiwei; Zhou, Jinjun; Liu, Jiahong; Zhang, Haixing; Wang, Jianhua; Xiang, Chenyao; Yang, Guiyu; Tang, Yun

    2017-01-04

    The comprehensive treatment project of groundwater over-exploitation in Hebei Province has been implemented for more than a year, and the effect of exploitation restriction is in urgent need of evaluation. This paper deals with Cheng'an County of Hebei Province as the research subject. Based on collected hydro-meteorological, socioeconomic, groundwater, and other related data, together with typical regional experimental research, this study generates the effective precipitation-groundwater exploitation (P-W) curve and accompanying research methods, and calculates the quantity of groundwater exploitation restriction. It analyzes the target completion status of groundwater exploitation restriction through water conservancy measures and agricultural practices of the groundwater over-exploitation comprehensive treatment project that was implemented in Cheng'an County in 2014. The paper evaluates the treatment effect of groundwater over-exploitation, as well as provides technical support for the effect evaluation of groundwater exploitation restriction of agricultural irrigation in Cheng'an County and relevant areas.

  8. 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.

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. 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...

  14. 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...

  15. 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.

  16. 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.

  17. Ground-water flow in the Gulf Coast aquifer systems, south-central United States

    USGS Publications Warehouse

    Williamson, A.K.; Grubb, H.F.

    2001-01-01

    The Gulf Coast regional aquifer systems constitute one of the largest, most complicated, and most interdependent aquifer systems in the United States. Ground-water flow in a 230,000-square-mile area of the south-central United States was modeled for the effect of withdrawing freshwater at the rate of nearly 10 billion gallons per day in 1985 from regional aquifers in the Mississippi Embayment, the Texas coastal uplands, and the coastal lowlands aquifer systems. The 1985 rate of pumping was three times the average rate of recharge to the aquifers before development. The report also estimates the effects of even greater withdrawal rates in the aquifer systems. About two-thirds of the water in the aquifers is saline to brine, which complicates the modeling. Land subsidence due to water withdrawal also was modeled.

  18. 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.

  19. 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.

  20. Monticello Mill Tailings Site Operable Unit III Annual Groundwater Report May 2014 Through April 2015, October 2015

    SciTech Connect

    Nguyen, Jason; Smith, Fred

    2015-10-01

    This report provides the annual analysis of water quality restoration progress, cumulative through April 2015, for Operable Unit (OU) III, surface water and groundwater, of the U.S. Department of Energy (DOE) Office of Legacy Management Monticello Mill Tailings Site (MMTS). The MMTS is a Comprehensive Environmental Response, Compensation, and Liability Act National Priorities List site located in and near the city of Monticello, San Juan County, Utah. MMTS comprises the 110-acre site of a former uranium- and vanadium-ore-processing mill (mill site) and 1,700 acres of surrounding private and municipal property. Milling operations generated 2.5 million cubic yards of waste (tailings) from 1942 to 1960. The tailings were impounded at four locations on the mill site. Inorganic constituents in the tailings drained from the impoundments to contaminate local surface water (Montezuma Creek) and groundwater in the underlying alluvial aquifer. Mill tailings dispersed by wind and water also contaminated properties surrounding and downstream of the mill site. Remedial actions to remove and isolate radiologically contaminated soil, sediment, and debris from the former mill site (OU I) and surrounding properties (OU II) were completed in 1999 with the encapsulation of the wastes in an engineered repository located on DOE property 1 mile south of the former mill site. Contamination of groundwater and surface water remains within OU III at levels that exceed water quality protection standards. Uranium is the primary contaminant of concern. LM implemented monitored natural attenuation with institutional controls as the OU III remedy in 2004. Because groundwater restoration proceeded more slowly than expected and did not meet performance criteria established in the OU III Record of Decision (June 2004), LM implemented a contingency action in 2009 by an Explanation of Significant Difference to include a pump-and-treat system using a single extraction well and treatment by zero

  1. 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

  2. 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

  3. Edible Oil Barriers for Treatment of Chlorinated Solvent Contaminated Groundwater

    DTIC Science & Technology

    2009-07-01

    Measurements 6-4 Laboratory Study: Biological Assay on Groundwater and Blended Sediment 6-5 Properties of Different Alkalis Used for pH Adjustments 6...of heavy metals (Cu, Hg, Zn) and some organic compounds can inhibit anaerobic biodegradation processes. A number of studies have shown that...different alkali materials to increase the pH of the aquifer. These included: hydrated lime (Ca(OH)2), magnesium hydroxide (Mg(OH)2), sodium hydroxide

  4. 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.

  5. 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.

  6. 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

  7. The handbook of groundwater engineering

    SciTech Connect

    Delleur, J.W.

    1998-12-31

    From an engineering perspective, this book provides a practical treatment of groundwater flow; substance transport, well construction, groundwater production, site characterization, and remediation of groundwater pollution.

  8. Status of groundwater quality in the Santa Barbara Study Unit, 2011: California GAMA Priority Basin Project

    USGS Publications Warehouse

    Davis, Tracy A.; Kulongoski, Justin T.

    2016-10-03

    Groundwater quality in the 48-square-mile Santa Barbara study unit was investigated in 2011 as part of the California State Water Resources Control Board’s Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project. The study unit is mostly in Santa Barbara County and is in the Transverse and Selected Peninsular Ranges hydrogeologic province. The GAMA Priority Basin Project is carried out by the U.S. Geological Survey in collaboration with the California State Water Resources Control Board and Lawrence Livermore National Laboratory.The GAMA Priority Basin Project was designed to provide a statistically unbiased, spatially distributed assessment of the quality of untreated groundwater in the primary aquifer system of California. 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 database for the Santa Barbara study unit. This status assessment is intended to characterize the quality of groundwater resources in the primary aquifer system of the Santa Barbara study unit, not the treated drinking water delivered to consumers by water purveyors.The status assessment for the Santa Barbara study unit was based on water-quality and ancillary data collected in 2011 by the U.S. Geological Survey from 23 sites and on water-quality data from the California Department of Public Health database for January 24, 2008–January 23, 2011. The data used for the assessment included volatile organic compounds; pesticides; pharmaceutical compounds; two constituents of special interest, perchlorate and N-nitrosodimethylamine (NDMA); and naturally present inorganic constituents, such as major ions and trace elements. Relative-concentrations (sample concentration divided by the health- or aesthetic-based benchmark concentration) were used to evaluate groundwater quality for those constituents that have federal or California regulatory and non

  9. 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.

  10. 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.

  11. Groundwater-quality data in the Monterey–Salinas shallow aquifer study unit, 2013: Results from the California GAMA Program

    USGS Publications Warehouse

    Goldrath, Dara A.; Kulongoski, Justin T.; Davis, Tracy A.

    2016-09-01

    constituents (trace elements, nutrients, major and minor ions, silica, total dissolved solids, and alkalinity) were collected at all 170 sites. In addition to these constituents, the samples from grid wells were analyzed for organic constituents (volatile organic compounds, pesticides and pesticide degradates), constituents of special interest (perchlorate and N-nitrosodimethylamine, or NDMA), radioactive constituents (radon-222 and gross-alpha and gross-beta radioactivity), and geochemical and age-dating tracers (stable isotopes of carbon in dissolved inorganic carbon, carbon-14 abundances, stable isotopes of hydrogen and oxygen in water, and tritium activities).Three types of quality-control samples (blanks, replicates, and matrix spikes) were collected at up to 11 percent of the wells in the Monterey–Salinas Shallow Aquifer study unit, and the results for these samples were used to evaluate the quality of the data from the groundwater samples. With the exception of trace elements, blanks rarely contained detectable concentrations of any constituent, indicating that contamination from sample-collection procedures was not a significant source of bias in the data for the groundwater samples. Low concentrations of some trace elements were detected in blanks; therefore, the data were re-censored at higher reporting levels. Replicate samples generally were within the limits of acceptable analytical reproducibility. The median values of matrix-spike recoveries were within the acceptable range (70 to 130 percent) for the volatile organic compounds (VOCs) and N-nitrosodimethylamine (NDMA), but were only approximately 64 percent for pesticides and pesticide degradates.The sample-collection protocols used in this study were designed to obtain representative samples of groundwater. The quality of groundwater can differ from the quality of drinking water because water chemistry can change as a result of contact with plumbing systems or the atmosphere; because of treatment

  12. Factors influencing ground-water recharge in the eastern United States

    USGS Publications Warehouse

    Nolan, B.T.; Healy, R.W.; Taber, P.E.; Perkins, K.; Hitt, K.J.; Wolock, D.M.

    2007-01-01

    Ground-water recharge estimates for selected locations in the eastern half of the United States were obtained by Darcian and chloride-tracer methods and compared using statistical analyses. Recharge estimates derived from unsaturated-zone (RUZC) and saturated-zone (RSZC) chloride mass balance methods are less variable (interquartile ranges or IQRs are 9.5 and 16.1 cm/yr, respectively) and more strongly correlated with climatic, hydrologic, land use, and sediment variables than Darcian estimates (IQR = 22.8 cm/yr). The unit-gradient Darcian estimates are a nonlinear function of moisture content and also reflect the uncertainty of pedotransfer functions used to estimate hydraulic parameters. Significance level is 0.3. Estimates of RSZC were evaluated using analysis of variance, multiple comparison tests, and an exploratory nonlinear regression (NLR) model. Recharge generally is greater in coastal plain surficial aquifers, fractured crystalline rocks, and carbonate rocks, or in areas with high sand content. Westernmost portions of the study area have low recharge, receive somewhat less precipitation, and contain fine-grained sediment. The NLR model simulates water input to the land surface followed by transport to ground water, depending on factors that either promote or inhibit water infiltration. The model explains a moderate amount of variation in the data set (coefficient of determination = 0.61). Model sensitivity analysis indicates that mean annual runoff, air temperature, and precipitation, and an index of ground-water exfiltration potential most influence estimates of recharge at sampled sites in the region. Soil characteristics and land use have less influence on the recharge estimates, but nonetheless are significant in the NLR model. ?? 2006 Elsevier B.V. All rights reserved.

  13. Geology, ground-water hydrology, geochemistry, and ground-water simulation of the Beaumont and Banning Storage Units, San Gorgonio Pass area, Riverside County, California

    USGS Publications Warehouse

    Rewis, Diane L.; Christensen, Allen H.; Matti, Jonathan; Hevesi, Joseph A.; Nishikawa, Tracy; Martin, Peter

    2006-01-01

    Ground water has been the only source of potable water supply for residential, industrial, and agricultural users in the Beaumont and Banning storage units of the San Gorgonio Pass area, Riverside County, California. Ground-water levels in the Beaumont area have declined as much as 100 feet between the early 1920s and early 2000s, and numerous natural springs have stopped flowing. In 1961, the San Gorgonio Pass Water Agency (SGPWA) entered into a contract with the California State Department of Water Resources to receive 17,300 acre-feet per year of water to be delivered by the California State Water Project (SWP) to supplement natural recharge. Currently (2005), a pipeline is delivering SWP water into the area, and the SGPWA is artificially recharging the ground-water system using recharge ponds located along Little San Gorgonio Creek in Cherry Valley with the SWP water. In addition to artificial recharge, SGPWA is considering the direct delivery of SWP water for the irrigation of local golf courses and for agricultural supply in lieu of ground-water pumpage. To better understand the potential hydrologic effects of different water-management alternatives on ground-water levels and movement in the Beaumont and Banning storage units, existing geohydrologic and geochemical data were compiled, new data from a basin-wide ground-water level and water-quality monitoring network were collected, monitoring wells were installed near the Little San Gorgonio Creek recharge ponds, geohydrologic and geochemical analyses were completed, and a ground-water flow simulation model was developed. The San Gorgonio Pass area was divided into several storage units on the basis of mapped or inferred faults. This study addresses primarily the Beaumont and Banning storage units. The geologic units in the study area were generalized into crystalline basement rocks and sedimentary deposits. The younger sedimentary deposits and the surficial deposits are the main water-bearing deposits in the

  14. 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.

  15. 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.

  16. 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.

  17. The application of illite supported nanoscale zero valent iron for the treatment of uranium contaminated groundwater.

    PubMed

    Jing, C; Landsberger, S; Li, Y L

    2017-09-01

    In this study, nanoscale zero valent iron I-NZVI was investigated as a remediation strategy for uranium contaminated groundwater from the former Cimarron Fuel Fabrication Site in Oklahoma, USA. The 1 L batch-treatment system was applied in the study. The result shows that 99.9% of uranium in groundwater was removed by I-NZVI within 2 h. Uranium concentration in the groundwater stayed around 27 μg/L, and there was no sign of uranium release into groundwater after seven days of reaction time. Meanwhile the release of iron was significantly decreased compared to NZVI which can reduce the treatment impact on the water environment. To study the influence of background pH of the treatment system on removal efficiency of uranium, the groundwater was adjusted from pH 2-10 before the addition of I-NZVI. The pH of the groundwater was from 2.1 to 10.7 after treatment. The removal efficiency of uranium achieved a maximum in neutral pH of groundwater. The desorption of uranium on the residual solid phase after treatment was investigated in order to discuss the stability of uranium on residual solids. After 2 h of leaching, 0.07% of the total uranium on residual solid phase was leached out in a HNO3 leaching solution with a pH of 4.03. The concentration of uranium in the acid leachate was under 3.2 μg/L which is below the EPA's maximum contaminant level of 30 μg/L. Otherwise, the concentration of uranium was negligible in distilled water leaching solution (pH = 6.44) and NaOH leaching solution (pH = 8.52). A desorption study shows that an acceptable amount of uranium on the residuals can be released into water system under strong acid conditions in short terms. For long term disposal management of the residual solids, the leachate needs to be monitored and treated before discharge into a hazardous landfill or the water system. For the first time, I-NZVI was applied for the treatment of uranium contaminated groundwater. These results provide proof that I-NZVI has

  18. Treatment of N-Nitrosodimethylamine (NDMA) in Groundwater Using a Fluidized Bed Bioreactor

    DTIC Science & Technology

    2014-01-01

    DEMONSTRATION N-nitrosodimethylamine (NDMA) is present in groundwater and drinking water from industrial , agricultural, water treatment , and military...bed makes it appreciably more efficient for water treatment than many other types of biological reactor systems. This reduces the reactor size and...subsequently, the cost of treatment . The pilot-scale FBR (1-5 gallons per minute [gpm] influent flow) was operated for ~1 year on the actual site water

  19. 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

  20. Two-stage removal of nitrate from groundwater using biological and chemical treatments.

    PubMed

    Ayyasamy, Pudukadu Munusamy; Shanthi, Kuppusamy; Lakshmanaperumalsamy, Perumalsamy; Lee, Soon-Jae; Choi, Nag-Choul; Kim, Dong-Ju

    2007-08-01

    In this study, we attempted to treat groundwater contaminated with nitrate using a two-stage removal system: one is biological treatment using the nitrate-degrading bacteria Pseudomonas sp. RS-7 and the other is chemical treatment using a coagulant. For the biological system, the effect of carbon sources on nitrate removal was first investigated using mineral salt medium (MSM) containing 500 mg l(-1) nitrate to select the most effective carbon source. Among three carbon sources, namely, glucose, starch and cellulose, starch at 1% was found to be the most effective. Thus, starch was used as a representative carbon source for the remaining part of the biological treatment where nitrate removal was carried out for MSM solution and groundwater samples containing 500 mg l(-1) and 460 mg l(-1) nitrate, respectively. About 86% and 89% of nitrate were removed from the MSM solution and groundwater samples, respectively at 72 h. Chemical coagulants such as alum, lime and poly aluminium chloride were tested for the removal of nitrate remaining in the samples. Among the coagulants, lime at 150 mg l(-1) exhibited the highest nitrate removal efficiency with complete disappearance for the MSM solutions. Thus, a combined system of biological and chemical treatments was found to be more effective for the complete removal of nitrate from groundwater.

  1. 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

  2. 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.

  3. Groundwater-quality data in the Santa Barbara study unit, 2011: results from the California GAMA Program

    USGS Publications Warehouse

    Davis, Tracy A.; Kulongoski, Justin T.; Belitz, Kenneth

    2013-01-01

    Groundwater quality in the 48-square-mile Santa Barbara study unit was investigated by the U.S. Geological Survey (USGS) from January to February 2011, 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 Santa Barbara study unit was the thirty-fourth study unit to be sampled as part of the GAMA-PBP. The GAMA Santa Barbara 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 those parts of the aquifers corresponding to the perforation intervals of wells listed in the California Department of Public Health (CDPH) database for the Santa Barbara 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 Santa Barbara study unit located in Santa Barbara and Ventura Counties, groundwater samples were collected from 24 wells. Eighteen 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 six wells were selected to aid in evaluation of water-quality issues (understanding wells). The groundwater samples were analyzed for 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 (trace

  4. Status and understanding of groundwater quality in the Sierra Nevada Regional study unit, 2008: California GAMA Priority Basin Project

    USGS Publications Warehouse

    Fram, Miranda S.; Belitz, Kenneth

    2014-01-01

    Statistical tests were used to evaluate relations between constituent concentrations and potential explanatory factors descriptive of land use, geography, depth, geochemical conditions, and groundwater age. Higher concentrations of trace elements, radioactive constituents, and constituents with aesthetic-based benchmarks generally were associated with anoxic conditions, higher pH, and location within a particular compositional band in the Sierra Nevada batholith corresponding to the southwestern part of the study unit. High concentrations of organic constituents generally were associated with greater proportions of urban land use. No significant relations were observed between the concentrations of organic constituents and measures of well depth or groundwater age, perhaps because of the high proportions of springs and modern groundwater in the dataset.

  5. 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.

  6. 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

  7. Groundwater resource development

    SciTech Connect

    Hamill, L.

    1986-01-01

    This book provides engineers with a treatment of the steps involved in the exploration and evaluation of aquifers, the construction and testing of water supply boreholes, and the management of the resource. The important subjects of water quality criteria, pollution hazards and modeling techniques are also included. Contents: Development of Groundwater Resources; Groundwater: Fundamentals; Groundwater Exploration; Assessment of Aquifer Recharge and Potential Well Yield; Groundwater Quality; Well Design and Construction; Aquifer Hydraulics and Pumping Tests; Groundwater Pollution; Groundwater Management; Groundwater Modeling Techniques.

  8. 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.

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

    USGS Publications Warehouse

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

    1997-01-01

    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 1993-94 as part of the U.S. Geological Survey's National Water-Quality Assessment Program. Samples were collected from 5 drinking-water wells, 12 springs, and 1g3 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 8 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 9 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 lifetime 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 xylenes (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 nonpoint sources, such as recharge of precipitation and storm-water runoff.

  10. 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)

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

    PubMed

    Einsiedl, Florian; Radke, Michael; Maloszewski, Piotr

    2010-09-20

    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 (3)H samples in groundwater over 27years 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 (3)H 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 microg/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. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  12. Natural zeolite permeable treatment wall for removing Sr-90 from groundwater.

    PubMed

    Seneca, Shannon M; Rabideau, Alan J

    2013-02-05

    Experimental and modeling studies were completed to investigate the potential performance of a sorbing permeable treatment wall (PTW) comprised of natural zeolite for removal of strontium-90 (Sr-90) from groundwater at the West Valley Demonstration Project (WVDP) near Buffalo, NY. Multiple column tests were performed at the University at Buffalo (UB) and WVDP for periods ranging from 6 months to 2 years; UB columns were supplied with synthetic groundwater referenced to anticipated field conditions, while radioactive groundwater obtained on site was used for the WVDP columns. The primary focus was on quantifying the competitive cation reactions among five cations (Na(+), K(+), Ca(2+), Mg(2+), Sr(2+)) and Sr-90 with data obtained from the column studies used to estimate Gaines-Thomas (GT) selectivity coefficients. The resulting six-solute transport model provided flexibility to explore the influence of PTW parameters on long-term PTW performance, including variations in Sr-90 concentrations and groundwater geochemistry. The natural zeolite PTW is a viable method for in situ removal of Sr-90 from groundwater and potentially applicable to other sites contaminated by Sr-90.

  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. Trends in groundwater quality in principal aquifers of the United States, 1988-2012

    USGS Publications Warehouse

    Lindsey, Bruce D.; Rupert, Michael G.

    2014-01-01

    The U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program analyzed trends in groundwater quality throughout the nation for the sampling period of 1988-2012. Trends were determined for networks (sets of wells routinely monitored by the USGS) for a subset of constituents by statistical analysis of paired water-quality measurements collected on a near-decadal time scale. The data set for chloride, dissolved solids, and nitrate consisted of 1,511 wells in 67 networks, whereas the data set for methyl tert-butyl ether (MTBE) consisted of 1, 013 wells in 46 networks. The 25 principal aquifers represented by these networks account for about 75 percent of withdrawals of groundwater used for drinking-water supply for the nation. Statistically significant changes in chloride, dissolved-solids, or nitrate concentrations were found in many well networks over a decadal period. Concentrations increased significantly in 48 percent of networks for chloride, 42 percent of networks for dissolved solids, and 21 percent of networks for nitrate. Chloride, dissolved solids, and nitrate concentrations decreased significantly in 3, 3, and 10 percent of the networks, respectively. The magnitude of change in concentrations was typically small in most networks; however, the magnitude of change in networks with statistically significant increases was typically much larger than the magnitude of change in networks with statistically significant decreases. The largest increases of chloride concentrations were in urban areas in the northeastern and north central United States. The largest increases of nitrate concentrations were in networks in agricultural areas. Statistical analysis showed 42 or the 46 networks had no statistically significant changes in MTBE concentrations. The four networks with statistically significant changes in MTBE concentrations were in the northeastern United States, where MTBE was widely used. Two networks had increasing concentrations, and two

  15. Influence of thermal treatments on radiocarbon dating of groundwater samples

    NASA Astrophysics Data System (ADS)

    Stanciu, Iuliana Madalina; Sava, Tiberiu Bogdan; Pacesila, Doru Gheorghe; Gaza, Oana; Simion, Corina Anca; Stefan, Bianca Maria; Sava, Gabriela Odilia; Ghita, Dan Gabriel; Mosu, Vasile

    2017-06-01

    Radiocarbon measurements of dissolved inorganic carbon (DIC) in water provides information about the formation of oceanic circulation of the water volumes, the hydrogeological systems, and also valuable information can be gained about the aquifer storage and the degree of containment relative to the surface waters. Radiocarbon dating refers to the determination of small quantities of the naturally occurring carbon 14 in the water, which can be integrated in the groundwater mass through the gaseous CO2, carbonaceous deposits dissolved by water and organic remains. The aim of this study is to investigate the influence of the temperature and pressure over the amount of each isotope of carbon during the sample preparation stage. The first step was to evaporate several underground water samples at 65°C under different conditions until the carbonates were obtained, then the CO2 was extracted with orto-phosphoric acid and transformed to graphite. The second step was to obtain graphite from an untreated water sample. Finally, the samples were measured with the 1MV Cockcroft-Walton Tandetron Accelerator by Accelerator Mass Spectrometry.

  16. 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.

    2016-03-29

    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

  17. 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

  18. Groundwater treatment as a source of indoor radon.

    PubMed

    Jantsikene, Alar; Kiisk, Madis; Suursoo, Siiri; Koch, Rein; Lumiste, Liie

    2014-11-01

    New Viimsi Parish water treatment plant (Northern Estonia) was investigated in order to determine whether the open filter columns serve as a source of (222)Rn generation in the treatment process and whether they influence indoor air (222)Rn activity concentrations. (222)Rn measurements of indoor (222)Rn were performed at different locations of the treatment plant; water samples from incoming raw water, from all the purification stages, consumers water and solid filter material from two filtration stages were analyzed.

  19. Seasonal forecasting of groundwater levels in natural aquifers in the United Kingdom

    NASA Astrophysics Data System (ADS)

    Mackay, Jonathan; Jackson, Christopher; Pachocka, Magdalena; Brookshaw, Anca; Scaife, Adam

    2014-05-01

    Groundwater aquifers comprise the world's largest freshwater resource and provide resilience to climate extremes which could become more frequent under future climate changes. Prolonged dry conditions can induce groundwater drought, often characterised by significantly low groundwater levels which may persist for months to years. In contrast, lasting wet conditions can result in anomalously high groundwater levels which result in flooding, potentially at large economic cost. Using computational models to produce groundwater level forecasts allows appropriate management strategies to be considered in advance of extreme events. The majority of groundwater level forecasting studies to date use data-based models, which exploit the long response time of groundwater levels to meteorological drivers and make forecasts based only on the current state of the system. Instead, seasonal meteorological forecasts can be used to drive hydrological models and simulate groundwater levels months into the future. Such approaches have not been used in the past due to a lack of skill in these long-range forecast products. However systems such as the latest version of the Met Office Global Seasonal Forecast System (GloSea5) are now showing increased skill up to a 3-month lead time. We demonstrate the first groundwater level ensemble forecasting system using a multi-member ensemble of hindcasts from GloSea5 between 1996 and 2009 to force 21 simple lumped conceptual groundwater models covering most of the UK's major aquifers. We present the results from this hindcasting study and demonstrate that the system can be used to forecast groundwater levels with some skill up to three months into the future.

  20. [Mobile stroke unit for prehospital stroke treatment].

    PubMed

    Walter, S; Grunwald, I Q; Fassbender, K

    2016-01-01

    The management of acute stroke patients suffers from several major problems in the daily clinical routine. In order to achieve optimal treatment a complex diagnostic work-up and rapid initiation of therapy are necessary; however, most patients arrive at hospital too late for any type of acute stroke treatment, although all forms of treatment are highly time-dependent according to the generally accepted "time is brain" concept. Recently, two randomized clinical trials demonstrated the feasibility of prehospital stroke diagnostic work-up and treatment. This was accomplished by use of a specialized ambulance, equipped with computed tomography for multimodal imaging and a point-of-care laboratory system. In both trials the results demonstrated a clear superiority of the prehospital treatment group with a significant reduction of treatment times, significantly increased number of patients treated within the first 60 min after symptom onset and an optimized triage to the correct target hospital. Currently, mobile stroke units are in operation in various countries and should lead to an improvement in stroke treatment; nevertheless, intensive research is still needed to analyze the best framework settings for prehospital stroke management.

  1. Innovative Approaches to Collaborative Groundwater Governance in the United States: Case Studies from Three High-Growth Regions in the Sun Belt

    NASA Astrophysics Data System (ADS)

    Megdal, Sharon B.; Gerlak, Andrea K.; Huang, Ling-Yee; Delano, Nathaniel; Varady, Robert G.; Petersen-Perlman, Jacob D.

    2017-05-01

    Groundwater is an increasingly important source of freshwater, especially where surface water resources are fully or over-allocated or becoming less reliable due to climate change. Groundwater reliance has created new challenges for sustainable management. This article examines how regional groundwater users coordinate and collaborate to manage shared groundwater resources, including attention to what drives collaboration. To identify and illustrate these facets, this article examines three geographically diverse cases of groundwater governance and management from the United States Sun Belt: Orange County Water District in southern California; Prescott Active Management Area in north-central Arizona; and the Central Florida Water Initiative in central Florida. These regions have different surface water laws, groundwater allocation and management laws and regulations, demographics, economics, topographies, and climate. These cases were selected because the Sun Belt faces similar pressures on groundwater due to historical and projected population growth and limited availability of usable surface water supplies. Collectively, they demonstrate groundwater governance trends in the United States, and illustrate distinctive features of regional groundwater management strategies. Our research shows how geophysical realities and state-level legislation have enabled and/or stimulated regions to develop groundwater management plans and strategies to address the specific issues associated with their groundwater resources. We find that litigation involvement and avoidance, along with the need to finance projects, are additional drivers of regional collaboration to manage groundwater. This case study underscores the importance of regionally coordinated and sustained efforts to address serious groundwater utilization challenges faced by the regions studied and around the world.

  2. Innovative Approaches to Collaborative Groundwater Governance in the United States: Case Studies from Three High-Growth Regions in the Sun Belt.

    PubMed

    Megdal, Sharon B; Gerlak, Andrea K; Huang, Ling-Yee; Delano, Nathaniel; Varady, Robert G; Petersen-Perlman, Jacob D

    2017-05-01

    Groundwater is an increasingly important source of freshwater, especially where surface water resources are fully or over-allocated or becoming less reliable due to climate change. Groundwater reliance has created new challenges for sustainable management. This article examines how regional groundwater users coordinate and collaborate to manage shared groundwater resources, including attention to what drives collaboration. To identify and illustrate these facets, this article examines three geographically diverse cases of groundwater governance and management from the United States Sun Belt: Orange County Water District in southern California; Prescott Active Management Area in north-central Arizona; and the Central Florida Water Initiative in central Florida. These regions have different surface water laws, groundwater allocation and management laws and regulations, demographics, economics, topographies, and climate. These cases were selected because the Sun Belt faces similar pressures on groundwater due to historical and projected population growth and limited availability of usable surface water supplies. Collectively, they demonstrate groundwater governance trends in the United States, and illustrate distinctive features of regional groundwater management strategies. Our research shows how geophysical realities and state-level legislation have enabled and/or stimulated regions to develop groundwater management plans and strategies to address the specific issues associated with their groundwater resources. We find that litigation involvement and avoidance, along with the need to finance projects, are additional drivers of regional collaboration to manage groundwater. This case study underscores the importance of regionally coordinated and sustained efforts to address serious groundwater utilization challenges faced by the regions studied and around the world.

  3. 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

  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. 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...

  6. 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...

  7. 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...

  8. 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...

  9. Groundwater Quality Data for the Tahoe-Martis Study Unit, 2007: Results from the California GAMA Program

    USGS Publications Warehouse

    Fram, Miranda S.; Munday, Cathy; Belitz, Kenneth

    2009-01-01

    Groundwater quality in the approximately 460-square-mile Tahoe-Martis study unit was investigated in June through September 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 the quality of raw groundwater used for public water supplies within the Tahoe-Martis study unit (Tahoe-Martis) and to facilitate statistically consistent comparisons of groundwater quality throughout California. Samples were collected from 52 wells in El Dorado, Placer, and Nevada Counties. Forty-one of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study area (grid wells), and 11 were selected to aid in evaluation of specific water-quality issues (understanding wells). The groundwater samples were analyzed for a large number of synthetic organic constituents (volatile organic compounds [VOC], pesticides and pesticide degradates, and pharmaceutical compounds), constituents of special interest (perchlorate and N-nitrosodimethylamine [NDMA]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial indicators. Naturally occurring isotopes (tritium, carbon-14, strontium isotope ratio, and stable isotopes of hydrogen and oxygen of water), and dissolved noble gases also were measured to help identify the sources and ages of the sampled groundwater. In total, 240 constituents and water-quality indicators were investigated. Three types of quality-control samples (blanks, replicates, and samples for matrix spikes) each were collected at 12 percent of the wells, and the

  10. 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

  11. Predicting geogenic arsenic contamination in shallow groundwater of south Louisiana, United States.

    PubMed

    Yang, Ningfang; Winkel, Lenny H E; Johannesson, Karen H

    2014-05-20

    Groundwater contaminated with arsenic (As) threatens the health of more than 140 million people worldwide. Previous studies indicate that geology and sedimentary depositional environments are important factors controlling groundwater As contamination. The Mississippi River delta has broadly similar geology and sedimentary depositional environments to the large deltas in South and Southeast Asia, which are severely affected by geogenic As contamination and therefore may also be vulnerable to groundwater As contamination. In this study, logistic regression is used to develop a probability model based on surface hydrology, soil properties, geology, and sedimentary depositional environments. The model is calibrated using 3286 aggregated and binary-coded groundwater As concentration measurements from Bangladesh and verified using 78 As measurements from south Louisiana. The model's predictions are in good agreement with the known spatial distribution of groundwater As contamination of Bangladesh, and the predictions also indicate high risk of As contamination in shallow groundwater from Holocene sediments of south Louisiana. Furthermore, the model correctly predicted 79% of the existing shallow groundwater As measurements in the study region, indicating good performance of the model in predicting groundwater As contamination in shallow aquifers of south Louisiana.

  12. Interactions of water quality and integrated groundwater management: exampled from the United States

    USDA-ARS?s Scientific Manuscript database

    Groundwater is available in many parts of the world, but the quality of the water may limit its use. Contaminants can limit the use of groundwater through concerns associated with human health, aquatic health, economic costs, or even societal perception. Given this broad range of concerns, this chap...

  13. 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

  14. Ammonia-Oxidizing Bacteria and Archaea in Groundwater Treatment and Drinking Water Distribution Systems▿ †

    PubMed Central

    van der Wielen, Paul W. J. J.; Voost, Stefan; van der Kooij, Dick

    2009-01-01

    The ammonia-oxidizing prokaryote (AOP) community in three groundwater treatment plants and connected distribution systems was analyzed by quantitative real-time PCR and sequence analysis targeting the amoA gene of ammonia-oxidizing bacteria (AOB) and archaea (AOA). Results demonstrated that AOB and AOA numbers increased during biological filtration of ammonia-rich anoxic groundwater, and AOP were responsible for ammonium removal during treatment. In one of the treatment trains at plant C, ammonia removal correlated significantly with AOA numbers but not with AOB numbers. Thus, AOA were responsible for ammonia removal in water treatment at one of the studied plants. Furthermore, an observed negative correlation between the dissolved organic carbon (DOC) concentration in the water and AOA numbers suggests that high DOC levels might reduce growth of AOA. AOP entered the distribution system in numbers ranging from 1.5 × 103 to 6.5 × 104 AOPs ml−1. These numbers did not change during transport in the distribution system despite the absence of a disinfectant residual. Thus, inactive AOP biomass does not seem to be degraded by heterotrophic microorganisms in the distribution system. We conclude from our results that AOA can be commonly present in distribution systems and groundwater treatment, where they can be responsible for the removal of ammonia. PMID:19465520

  15. Ammonia-oxidizing bacteria and archaea in groundwater treatment and drinking water distribution systems.

    PubMed

    van der Wielen, Paul W J J; Voost, Stefan; van der Kooij, Dick

    2009-07-01

    The ammonia-oxidizing prokaryote (AOP) community in three groundwater treatment plants and connected distribution systems was analyzed by quantitative real-time PCR and sequence analysis targeting the amoA gene of ammonia-oxidizing bacteria (AOB) and archaea (AOA). Results demonstrated that AOB and AOA numbers increased during biological filtration of ammonia-rich anoxic groundwater, and AOP were responsible for ammonium removal during treatment. In one of the treatment trains at plant C, ammonia removal correlated significantly with AOA numbers but not with AOB numbers. Thus, AOA were responsible for ammonia removal in water treatment at one of the studied plants. Furthermore, an observed negative correlation between the dissolved organic carbon (DOC) concentration in the water and AOA numbers suggests that high DOC levels might reduce growth of AOA. AOP entered the distribution system in numbers ranging from 1.5 x 10(3) to 6.5 x 10(4) AOPs ml(-1). These numbers did not change during transport in the distribution system despite the absence of a disinfectant residual. Thus, inactive AOP biomass does not seem to be degraded by heterotrophic microorganisms in the distribution system. We conclude from our results that AOA can be commonly present in distribution systems and groundwater treatment, where they can be responsible for the removal of ammonia.

  16. Ground-Water Quality Data in the Middle Sacramento Valley Study Unit, 2006 - Results from the California GAMA Program

    USGS Publications Warehouse

    Schmitt, Stephen J.; Fram, Miranda S.; Milby Dawson, Barbara J.; Belitz, Kenneth

    2008-01-01

    Ground-water quality in the approximately 3,340 square mile Middle Sacramento Valley study unit (MSACV) was investigated from June through September, 2006, as part of the California 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 Middle Sacramento Valley study was designed to provide a spatially unbiased assessment of raw ground-water quality within MSACV, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 108 wells in Butte, Colusa, Glenn, Sutter, Tehama, Yolo, and Yuba Counties. Seventy-one wells were selected using a randomized grid-based method to provide statistical representation of the study unit (grid wells), 15 wells were selected to evaluate changes in water chemistry along ground-water flow paths (flow-path wells), and 22 were shallow monitoring wells selected to assess the effects of rice agriculture, a major land use in the study unit, on ground-water chemistry (RICE wells). The 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, and pharmaceutical compounds), constituents of special interest (perchlorate, N-nitrosodimethylamine [NDMA], and 1,2,3-trichloropropane [1,2,3-TCP]), 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. Quality-control samples (blanks

  17. Implications of Projected Climate Change for Groundwater Recharge in the Western United States

    NASA Technical Reports Server (NTRS)

    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.; hide

    2016-01-01

    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 degrees 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

  18. Implications of Projected Climate Change for Groundwater Recharge in the Western United States

    NASA Technical Reports Server (NTRS)

    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, Kristin L.; Niraula, Rewati; Rodell, Matthew; Scanlon, Bridget R.; Singha, Kamini; Walvoord, Michelle A.

    2016-01-01

    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 degrees 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

  19. Electrically Induced Redox Barriers for Treatment of Groundwater

    DTIC Science & Technology

    2008-12-01

    2  Methods and Materials...9  Methods and Materials...electrodes that provide equivalent or better performance in terms of electrode longevity and/or treatment efficacy. Methods and Materials Primary

  20. Laboratory evaluation of the potential for in situ treatment of chromate-contaminated groundwater by chemical precipitation

    SciTech Connect

    Thornton, E.C.; Beck, M.A.; Jurgensmeier, C.A.

    1995-03-01

    The objective of this paper is to present the results of a series of small-scale batch tests performed to assess the effectiveness of chemical precipitation in the remediation of chromate-contaminated groundwater. These tests involved treatment of chromate solutions with ferrous and sulfide ions. In addition, tests were conducted that involved treatment of mixtures of chromate-contaminated groundwater and uncontaminated soil with the ferrous ion. A combination of ferrous sulfate and sodium sulfide was also tested in the groundwater treatment tests, since this approach has been shown to be an efficient method for treating electroplating wastewaters.

  1. 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.

  2. 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

  3. An Effect Analysis of Comprehensive Treatment of Groundwater Over-Exploitation in Cheng’an County, Hebei Province, China

    PubMed Central

    Shao, Weiwei; Zhou, Jinjun; Liu, Jiahong; Zhang, Haixing; Wang, Jianhua; Xiang, Chenyao; Yang, Guiyu; Tang, Yun

    2017-01-01

    The comprehensive treatment project of groundwater over-exploitation in Hebei Province has been implemented for more than a year, and the effect of exploitation restriction is in urgent need of evaluation. This paper deals with Cheng’an County of Hebei Province as the research subject. Based on collected hydro-meteorological, socioeconomic, groundwater, and other related data, together with typical regional experimental research, this study generates the effective precipitation–groundwater exploitation (P-W) curve and accompanying research methods, and calculates the quantity of groundwater exploitation restriction. It analyzes the target completion status of groundwater exploitation restriction through water conservancy measures and agricultural practices of the groundwater over-exploitation comprehensive treatment project that was implemented in Cheng’an County in 2014. The paper evaluates the treatment effect of groundwater over-exploitation, as well as provides technical support for the effect evaluation of groundwater exploitation restriction of agricultural irrigation in Cheng’an County and relevant areas. PMID:28054979

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. Probability of detecting perchlorate under natural conditions in deep groundwater in California and the southwestern United States.

    PubMed

    Fram, Miranda S; Belitz, Kenneth

    2011-02-15

    We use data from 1626 groundwater samples collected in California, primarily from public drinking water supply wells, to investigate the distribution of perchlorate in deep groundwater under natural conditions. The wells were sampled for the California Groundwater Ambient Monitoring and Assessment Priority Basin Project. We develop a logistic regression model for predicting probabilities of detecting perchlorate at concentrations greater than multiple threshold concentrations as a function of climate (represented by an aridity index) and potential anthropogenic contributions of perchlorate (quantified as an anthropogenic score, AS). AS is a composite categorical variable including terms for nitrate, pesticides, and volatile organic compounds. Incorporating water-quality parameters in AS permits identification of perturbation of natural occurrence patterns by flushing of natural perchlorate salts from unsaturated zones by irrigation recharge as well as addition of perchlorate from industrial and agricultural sources. The data and model results indicate low concentrations (0.1-0.5 μg/L) of perchlorate occur under natural conditions in groundwater across a wide range of climates, beyond the arid to semiarid climates in which they mostly have been previously reported. The probability of detecting perchlorate at concentrations greater than 0.1 μg/L under natural conditions ranges from 50-70% in semiarid to arid regions of California and the Southwestern United States to 5-15% in the wettest regions sampled (the Northern California coast). The probability of concentrations above 1 μg/L under natural conditions is low (generally <3%).

  9. Probability of detecting perchlorate under natural conditions in deep groundwater in California and the Southwestern United States

    USGS Publications Warehouse

    Fram, Miranda S.; Belitz, Kenneth

    2011-01-01

    We use data from 1626 groundwater samples collected in California, primarily from public drinking water supply wells, to investigate the distribution of perchlorate in deep groundwater under natural conditions. The wells were sampled for the California Groundwater Ambient Monitoring and Assessment Priority Basin Project. We develop a logistic regression model for predicting probabilities of detecting perchlorate at concentrations greater than multiple threshold concentrations as a function of climate (represented by an aridity index) and potential anthropogenic contributions of perchlorate (quantified as an anthropogenic score, AS). AS is a composite categorical variable including terms for nitrate, pesticides, and volatile organic compounds. Incorporating water-quality parameters in AS permits identification of perturbation of natural occurrence patterns by flushing of natural perchlorate salts from unsaturated zones by irrigation recharge as well as addition of perchlorate from industrial and agricultural sources. The data and model results indicate low concentrations (0.1-0.5 μg/L) of perchlorate occur under natural conditions in groundwater across a wide range of climates, beyond the arid to semiarid climates in which they mostly have been previously reported. The probability of detecting perchlorate at concentrations greater than 0.1 μg/L under natural conditions ranges from 50-70% in semiarid to arid regions of California and the Southwestern United States to 5-15% in the wettest regions sampled (the Northern California coast). The probability of concentrations above 1 μg/L under natural conditions is low (generally <3%).

  10. 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.

  11. Electrokinetic treatment of hazardous wastes in soil and groundwater

    SciTech Connect

    Loo, W.W.

    1995-09-01

    Electrokinetic (EK) treatment processes are recognized by the US department of Defense, US Department of Energy, and the US EPA as the most potentially cost effective treatment of hazardous wastes. Recently, EK has attracted the attention of Dupont, General Electric, and Monsanto for various aspects of hazardous waste treatment. Electrolysis and electro-osmosis are known electrokinetic processes. Electrolysis is one of the principal industrial process used in the production of aluminum, chlorine, metal plating, welding, corrosion protection, etc. Electro-osmosis is a very well established process used to dewater and stabilize the clayey foundations of buildings and structures. These processes are very effective in the treatment of hazardous metals and organic compounds in soil, sludge, and water. Electrolysis can be applied in both permeable and impermeable media. It can be used as a neutralization process for pH control. It can also be used for the isolation or capture of metallic ions, or positively charged ions, at and near the cathode electrode. and negatively charged ions at and near the anode electrode. Electrolyis will also oxidize petroleum hydrocarbons and benzene-based organic chemicals such as PCBs, pesticides, and PAHs. Electro-osmosis can be used in the treatment of hazardous chemicals in silty and clayey material. The electro-osmotic process causes and imbalance of charge bonds in clayey material that results in clay compaction and chemical desorption. The compaction and desorption processes will reduce the cleanup time and are particularly successful in the desorption of organic chemicals and metals from clayey materials. This accelerates and improves the performance of typically inefficient pump and treat projects. Electrokinetic processes can be applied both above ground (ex situ) or in the subsurface (in situ).

  12. 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).

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

    USGS Publications Warehouse

    Bennett, George Luther; 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

  14. Ex situ groundwater treatment triggering the mobilization of geogenic uranium from aquifer sediments.

    PubMed

    Banning, Andre; Pawletko, Nadine; Röder, Julia; Kübeck, Christine; Wisotzky, Frank

    2017-06-01

    Uranium (U) concentrations in groundwater extracted for drinking water usage from a Quaternary fluvial aquifer partly exceed the German drinking water guideline of 10μgL(-1). Responsible sources and mobilization processes were unknown and gave rise to this study. Land use of the watershed is mainly agricultural leading to groundwater nitrate concentrations >50mgL(-1) and a need for water treatment prior to utilization as drinking water. This is successfully accomplished by addition of nutrients triggering bacterial nitrate reduction, followed by the addition of NaOH for water softening and CO2 for pH adjustment, with subsequent reinfiltration into the aquifer. Three boreholes were drilled to obtain a total of 127 solid samples from Quaternary and underlying Tertiary sediments. Geochemistry and mineralogy were assessed using elemental analysis (CS, ICP-MS), X-ray diffraction and scanning electron microscopy to complement hydrochemical data and unravel U occurrence in the subsurface. Solid phase U fractionation was characterized by a sequential extraction procedure, U remobilization potential by a 137days column experiment. Shallow Quaternary sediments yielded low U contents <1μgg(-1), higher values were found in depths of more than 20m below ground surface. Here, strata of elevated Corg and Cinorg contain up to 14μgg(-1) U, mainly bound in organic and carbonate fractions. Groundwater U concentrations >10μgL(-1) almost exclusively appear in this same depth range, and only in wells influenced by water treatment runoff. Results suggest that the applied water treatment approach triggers U remobilization from geogenic sources in the aquifer. The most probable mechanism is dissolution of U bearing calcite induced by CO2 application; redox reactions and pH-driven desorption appear to play a minor role in mobilization. We conclude that groundwater treatment should carefully account for unwanted hydrogeochemical side effects triggering the mobilization of geogenic trace

  15. Edible Oil Barriers for Treatment of Chlorinated Solvent and Perchlorate-Contaminated Groundwater

    DTIC Science & Technology

    2010-02-01

    OBJECTIVES OF THE DEMONSTRATION The project goals were to: (1) demonstrate and evaluate use of an edible -oil-in- water emulsion as the substrate for...ESTCP Cost and Performance Report ENVIRONMENTAL SECURITY TECHNOLOGY CERTIFICATION PROGRAM U.S. Department of Defense (ER-0221) Edible Oil Barriers...AND SUBTITLE Edible Oil Barriers for Treatment of Chlorinated Solvent and Perchlorate-Contaminated Groundwater 5a. CONTRACT NUMBER 5b. GRANT NUMBER

  16. Proven Alternatives for Aboveground Treatment of Arsenic in Groundwater

    DTIC Science & Technology

    2002-10-01

    nanofiltration and reverse osmosis treatment systems, both of which have been used to treat arsenic. Although nanofiltration and reverse osmosis are...UF) • Nanofiltration (NF) • Reverse osmosis (RO) Technology Description and Principles Contaminated Water Membranes RejectRecycle Effluent Model of a...Membrane Filtration System 5.0 MEMBRANE FILTRATION FOR ARSENIC There are four types of membrane processes: reverse osmosis (RO), nanofiltration (NF

  17. 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)

  18. Pesticides in groundwater of the United States: decadal-scale changes, 1993-2011

    USGS Publications Warehouse

    Toccalino, Patricia L.; Gilliom, Robert J.; Lindsey, Bruce D.; Rupert, Michael G.

    2014-01-01

    The national occurrence of 83 pesticide compounds in groundwater of the United States and decadal-scale changes in concentrations for 35 compounds were assessed for the 20-year period from 1993–2011. Samples were collected from 1271 wells in 58 nationally distributed well networks. Networks consisted of shallow (mostly monitoring) wells in agricultural and urban land-use areas and deeper (mostly domestic and public supply) wells in major aquifers in mixed land-use areas. Wells were sampled once during 1993–2001 and once during 2002–2011. Pesticides were frequently detected (53% of all samples), but concentrations seldom exceeded human-health benchmarks (1.8% of all samples). The five most frequently detected pesticide compounds—atrazine, deethylatrazine, simazine, metolachlor, and prometon—each had statistically significant (p < 0.1) changes in concentrations between decades in one or more categories of well networks nationally aggregated by land use. For agricultural networks, concentrations of atrazine, metolachlor, and prometon decreased from the first decade to the second decade. For urban networks, deethylatrazine concentrations increased and prometon concentrations decreased. For major aquifers, concentrations of deethylatrazine and simazine increased. The directions of concentration changes for individual well networks generally were consistent with changes determined from nationally aggregated data. Altogether, 36 of the 58 individual well networks had statistically significant changes in concentrations of one or more pesticides between decades, with the majority of changes attributed to the five most frequently detected pesticide compounds. The magnitudes of median decadal-scale concentration changes were small—ranging from −0.09 to 0.03 µg/L—and were 35- to 230,000-fold less than human-health benchmarks.

  19. Pesticides in groundwater of the United States: decadal-scale changes, 1993-2011.

    PubMed

    Toccalino, Patricia L; Gilliom, Robert J; Lindsey, Bruce D; Rupert, Michael G

    2014-09-01

    The national occurrence of 83 pesticide compounds in groundwater of the United States and decadal-scale changes in concentrations for 35 compounds were assessed for the 20-year period from 1993-2011. Samples were collected from 1271 wells in 58 nationally distributed well networks. Networks consisted of shallow (mostly monitoring) wells in agricultural and urban land-use areas and deeper (mostly domestic and public supply) wells in major aquifers in mixed land-use areas. Wells were sampled once during 1993-2001 and once during 2002-2011. Pesticides were frequently detected (53% of all samples), but concentrations seldom exceeded human-health benchmarks (1.8% of all samples). The five most frequently detected pesticide compounds-atrazine, deethylatrazine, simazine, metolachlor, and prometon-each had statistically significant (p < 0.1) changes in concentrations between decades in one or more categories of well networks nationally aggregated by land use. For agricultural networks, concentrations of atrazine, metolachlor, and prometon decreased from the first decade to the second decade. For urban networks, deethylatrazine concentrations increased and prometon concentrations decreased. For major aquifers, concentrations of deethylatrazine and simazine increased. The directions of concentration changes for individual well networks generally were consistent with changes determined from nationally aggregated data. Altogether, 36 of the 58 individual well networks had statistically significant changes in concentrations of one or more pesticides between decades, with the majority of changes attributed to the five most frequently detected pesticide compounds. The magnitudes of median decadal-scale concentration changes were small-ranging from -0.09 to 0.03 µg/L-and were 35- to 230,000-fold less than human-health benchmarks.

  20. The use of zero-valent iron for groundwater remediation and wastewater treatment: a review.

    PubMed

    Fu, Fenglian; Dionysiou, Dionysios D; Liu, Hong

    2014-02-28

    Recent industrial and urban activities have led to elevated concentrations of a wide range of contaminants in groundwater and wastewater, which affect the health of millions of people worldwide. In recent years, the use of zero-valent iron (ZVI) for the treatment of toxic contaminants in groundwater and wastewater has received wide attention and encouraging treatment efficiencies have been documented. This paper gives an overview of the recent advances of ZVI and progress obtained during the groundwater remediation and wastewater treatment utilizing ZVI (including nanoscale zero-valent iron (nZVI)) for the removal of: (a) chlorinated organic compounds, (b) nitroaromatic compounds, (c) arsenic, (d) heavy metals, (e) nitrate, (f) dyes, and (g) phenol. Reaction mechanisms and removal efficiencies were studied and evaluated. It was found that ZVI materials with wide availability have appreciable removal efficiency for several types of contaminants. Concerning ZVI for future research, some suggestions are proposed and conclusions have been drawn. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Net recharge vs. depth to groundwater relationship in the Platte River Valley of Nebraska, United States.

    PubMed

    Szilagyi, Jozsef; Zlotnik, Vitaly A; Jozsa, Janos

    2013-01-01

    One-km resolution MODIS-based mean annual evapotranspiration (ET) estimates in combination with PRISM precipitation rates were correlated with depth to groundwater (d) values in the wide alluvial valley of the Platte River in Nebraska for obtaining a net recharge (Rn) vs. d relationship. MODIS cells with irrigation were excluded, yielding a mixture of predominantly range, pasture, grass, and riparian forest covers on sandy soils with a shallow groundwater table. The transition depth (dt ) between negative and positive values of the net groundwater recharge was found to be at about 2 (±1) m. Within 1 (±1) m of the surface and at a depth larger than about 7 to 8 (±1) m, the mean annual net recharge became independent of d at a level of about -4 (±12)% and 13 (±10)%, respectively, of the mean annual precipitation rate. The obtained Rn(d) relationship is based on a calibration-free ET estimation method and may help in obtaining the net recharge in shallow groundwater areas of negligible surface runoff where sufficient groundwater-depth data exist. © 2012, The Author(s). Groundwater © 2012, National Ground Water Association.

  2. 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

  3. 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

  4. 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

  5. Application of Horizontal Flow Treatment Wells for In Situ Treatment of MTBE-Contaminated GroundWater

    DTIC Science & Technology

    2004-03-01

    these properties, some remediation technologies such as vapor extraction and granular activated carbon adsorption are not as effective for MTBE as...contaminated groundwater. HFTWs consist of two dual-screened treatment wells. One well operates in an upflow mode, with MTBE-contaminated water extracted ...mode, extracting water through the upper screen and injecting it through the lower. As the MTBE-contaminated water flows through the wells, an

  6. 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

  7. Chloroethene dechlorination in acidic groundwater: Implications for combining fenton's treatment with natural attenuation

    USGS Publications Warehouse

    Bradley, Paul M.; Singletary , Michael A.; Chapelle, Francis H.

    2007-01-01

    A sulfuric acid leak in 1988 at a chloroethene-contaminated groundwater site at the Naval Air Station Pensacola has resulted in a long-term record of the behavior of chloroethene contaminants at low pH and a unique opportunity to assess the potential impact of source area treatment technologies, which involve acidification of the groundwater environment (e.g., Fenton's-based in situ chemical oxidation), on downgradient natural attenuation processes. The greater than 75 percent decrease in trichloroethene (TCE) concentrations and the shift in contaminant composition toward predominantly reduced daughter products (dichloroethene [DCE] and vinyl chloride [VC]) that were observed along a 30-m groundwater flow path characterized by highly acidic conditions (pH = 3.5 ± 0.4) demonstrated that chloroethene reductive dechlorination can continue to be efficient under persistent acidic conditions. The detection of Dehalococcoides-type bacteria within the sulfuric acid/chloroethene co-contaminant plume was consistent with biotic chloroethene reductive dechlorination. Microcosm studies conducted with 14C-TCE and 14C-VC confirmed biotic reductive dechlorination in sediment collected from within the sulfuric acid/chloroethene co-contaminant plume. Microcosms prepared with sediment from two other locations within the acid plume, however, demonstrated only a limited mineralization to 14CO2 and 14CO, which was attributed to abiotic degradation because no significant differences were observed between experimental and autoclaved control treatments. These results indicated that biotic and abiotic mechanisms contributed to chloroethene attenuation in the acid plume at NAS Pensacola and that remediation techniques involving acidification of the groundwater environment (e.g., Fenton's-based source area treatment) do not necessarily preclude efficient chloroethene degradation.

  8. Risk of nitrate in groundwaters of the United States - A national perspective

    USGS Publications Warehouse

    Nolan, B.T.; Ruddy, B.C.; Hitt, K.J.; Helsel, D.R.

    1997-01-01

    Nitrate contamination of groundwater occurs in predictable patterns, based on findings of the U.S. Geological Survey's (USGS) National Water Quality Assessment (NAWQA) Program. The NAWQA Program was begun in 1991 to describe the quality of the Nation's water resources, using nationally consistent methods. Variables affecting nitrate concentration in groundwater were grouped as 'input' factors (population density end the amount of nitrogen contributed by fertilizer, manure, and atmospheric sources) and 'aquifer vulnerability' factors (soil drainage characteristic and the ratio of woodland acres to cropland acres in agricultural areas) and compiled in a national map that shows patterns of risk for nitrate contamination of groundwater. Areas with high nitrogen input, well-drained soils, and low woodland to cropland ratio have the highest potential for contamination of shallow groundwater by nitrate. Groundwater nitrate data collected through 1992 from wells less than 100 ft deep generally verified the risk patterns shown on the national map. Median nitrate concentration was 0.2 mg/L in wells representing the low-risk group, and the maximum contaminant level (MCL) was exceeded in 3% of the wells. In contrast, median nitrate concentration was 4.8 mg/L in wells representing the high-risk group, and the MCL was exceeded in 25% of the wells.Nitrate contamination of groundwater occurs in predictable patterns, based on findings of the U.S. Geological Survey's (USGS) National Water Quality Assessment (NAWQA) Program. The NAWQA Program was begun in 1991 to describe the quality of the Nation's water resources, using nationally consistent methods. Variables affecting nitrate concentration in groundwater were grouped as `input' factors (population density and the amount of nitrogen contributed by fertilizer, manure, and atmospheric sources) and `aquifer vulnerability' factors (soil drainage characteristic and the ratio of woodland acres to cropland acres in agricultural areas

  9. Hydrogeology, distribution, and volume of saline groundwater in the southern midcontinent and adjacent areas of the United States

    USGS Publications Warehouse

    Osborn, Noël I.; Smith, S. Jerrod; Seger, Christian H.

    2013-01-01

    The hydrogeology, distribution, and volume of saline water in 22 aquifers in the southern midcontinent of the United States were evaluated to provide information about saline groundwater resources that may be used to reduce dependency on freshwater resources. Those aquifers underlie six States in the southern midcontinent—Arkansas, Kansas, Louisiana, Missouri, Oklahoma, and Texas—and adjacent areas including all or parts of Alabama, Colorado, Florida, Illinois, Kentucky, Mississippi, Nebraska, New Mexico, South Dakota, Tennessee, and Wyoming and some offshore areas of the Gulf of Mexico. Saline waters of the aquifers were evaluated by defining salinity zones; digitizing data, primarily from the Regional Aquifer-System Analysis Program of the U.S. Geological Survey; and computing the volume of saline water in storage. The distribution of saline groundwater in the southern midcontinent is substantially affected by the hydrogeology and groundwater-flow systems of the aquifers. Many of the aquifers in the southern midcontinent are underlain by one or more aquifers, resulting in vertically stacked aquifers containing groundwaters of varying salinity. Saline groundwater is affected by past and present hydrogeologic conditions. Spatial variation of groundwater salinity in the southern midcontinent is controlled primarily by locations of recharge and discharge areas, groundwater-flow paths and residence time, mixing of freshwater and saline water, and interactions with aquifer rocks and sediments. The volume calculations made for the evaluated aquifers in the southern midcontinent indicate that about 39,900 million acre-feet (acre-ft) of saline water is in storage. About 21,600 million acre-ft of the water in storage is slightly to moderately saline (1,000–10,000 milligrams per liter [mg/L] dissolved solids), and about 18,300 million acre-ft is very saline (10,000–35,000 mg/L dissolved solids). The largest volumes of saline water are in the coastal lowlands (about

  10. Estimates of groundwater age from till and carbonate bedrock hydrogeologic units at Jefferson Proving Ground, Southeastern Indiana, 2007-08

    USGS Publications Warehouse

    Buszka, Paul M.; Lampe, David C.; Egler, Amanda L.

    2010-01-01

    During 2007-08, the U.S. Geological Survey, in cooperation with the U.S. Department of the Army, conducted a study to evaluate the relative age of groundwater in Pre-Wisconsinan till and underlying shallow and deep carbonate bedrock units in and near an area at Jefferson Proving Ground (JPG), southeastern Indiana, which was used during 1984-94 to test fire depleted uranium (DU) penetrators. The shallow carbonate unit includes about the upper 40 feet of bedrock below the bedrock-till surface; the deeper carbonate unit includes wells completed at greater depth. Samples collected during April 2008 from 15 wells were analyzed for field water-quality parameters, dissolved gases, tritium, and chlorofluorocarbon (CFC) compounds; samples from 14 additional wells were analyzed for tritium only. Water-level gradients in the Pre-Wisconsinan till and the shallow carbonate unit were from topographically higher areas toward Big Creek and Middle Fork Creek, and their tributaries. Vertical gradients were strongly downward from the shallow carbonate unit toward the deep carbonate unit at 3 of 4 paired wells where water levels recovered after development; indicating the general lack of flow between the two units. The lack of post development recovery of water levels at 4 other wells in the deep carbonate unit indicate that parts of that unit have no appreciable permeability. CFC and tritium-based age dates of Pre-Wisconsinan till groundwater are consistent with infiltration of younger (typically post-1960 age) recharge that 'mixes' with older recharge from less permeable or less interconnected strata. Part of the recharge to three till wells dated from the early to mid-1980s (JPG-DU-03O, JPG-DU-09O, and JPG-DU-10O). Age dates of young recharge in water from two till wells predated 1980 (JPG-DU-04O and JPG-DU-06O). Tritium-based age dates of water from seven other till wells indicated post-1972 age recharge. Most wells in the Pre-Wisconsinan till have the potential to produce

  11. 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

  12. 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

  13. 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.

  14. Treatment of landfill leachate-impacted groundwater using cascade aeration and constructed wetlands

    SciTech Connect

    Loer, J.; O`Flanagan, B.; Fellows, W.

    1995-12-31

    At an unlined municipal solid waste landfill, heavy metal and toxic organic compounds present in leachate have impacted groundwater, necessitating extraction and treatment of the contaminated groundwater. A remedial design relying on a natural systems engineering approach will take advantage of existing contours (gravity flow) and surroundings (wetlands), and will limit energy inputs and eliminate chemical inputs. Impacted groundwater will be extracted, and aerated via a cascade constructed of polypropylene sheets fabricated into {open_quotes}step{close_quotes} sections and set into a side slope of the landfill. Volatilization of organics and oxidation of iron and heavy metals to insoluble compounds will occur during cascading and will continue within a sedimentation basin where settling of iron precipitates will induce co-settling of heavy metal precipitates. Following the sedimentation basin, a constructed wetland containing both aerobic zones and anaerobic zones will provide additional treatment of remaining solids and heavy metals, before surface discharge. Use of a natural systems approach significantly reduces operating costs compared to a mechanical-aeration, chemical-precipitation system, and is more aesthetically pleasing and suited to the remote locale. The system is under construction and seasonal operation will begin in spring 1996.

  15. Ground-water flow in the Gulf Coast aquifer systems, south central United States; a preliminary analysis

    USGS Publications Warehouse

    Williamson, A.K.; Grubb, H.F.; Weiss, J.S.

    1990-01-01

    A major objective of the Gulf Coast Regional Aquifer-System Analysis is to use digital models of regional groundwater flow systems to develop better understanding and to improve management of the resource. Modeling is used to synthesize information about the aquifer systems and to test hypotheses about the relative importance of the components of the systems. The 290,000-sq mile study area in the Gulf of Mexico Coastal Plain includes the Mississippi embayment, Gulf Coastal Plain of Texas, and the Continental Shelf that are underlain by deposits of Tertiary and younger age, which contain fresh and saline water. A 10-layer, finite-difference, variable density model, with blocks 10 miles on a side, was used to simulate groundwater flow before development and in 1980, assuming steady- state conditions. Preliminary results indicate that the major factors controlling predevelopment regional flow are the topography, land-surface outcrop pattern, and geometry of aquifers and confining units. Geologic structure and the distribution of precipitation were less significant factors. The density of saline water in the deeper parts of the aquifer system probably has a substantial effect on regional groundwater flow that extends into the freshwater part of the system. Variable water density may be a significant driving force that transports salt great distances in many directions, including updip. The distribution and rates of regional recharge and discharge have been substantially changed by development. Groundwater pumpage in 1980 was about five times the value of predevelopment regional recharge. About 80% of the pumpage was supplied from increased regional recharge. Also resistance to vertical flow caused by many fine-grained beds within the permeable zones can be as important as resistance caused by regional confining units. (USGS)

  16. Groundwater-quality data in the Tulare Shallow Aquifer Study Unit, 2014-2015: Results from the California GAMA Priority Basin Project

    USGS Publications Warehouse

    Bennett, George L.; Fram, Miranda S.; Johnson, Tyler

    2017-01-01

    The U.S. Geological Survey collected groundwater samples from 95 domestic wells in Tulare and Kings Counties, California in 2014-2015. The wells were sampled for the Tulare Shallow Aquifer Study Unit of the California State Water Resources Control Board Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project’s assessment of the quality of groundwater resources used for domestic drinking water supply. Domestic wells commonly are screened at shallower depths than are public-supply wells. The Tulare Shallow Aquifer Study Unit includes the Kaweah, Tule, and Tulare Lake subbasins of the San Joaquin Valley groundwater basin and adjacent areas of the Sierra Nevada. The study unit was divided into equal area grid cells and one domestic well was sampled in each cell. Groundwater samples were analyzed for field water-quality parameters, volatile organic compounds, pesticides and pesticide degradates, nutrients, major ions and trace elements, gross alpha and gross beta particle activities, noble gases, tritium, carbon-14 in dissolved inorganic carbon, stable isotopic ratios of water and dissolved nitrate, and microbial indicators.These data support the following publication:Fram, M.S., 2017, Groundwater Quality in the Shallow Aquifers of the Tulare, Kaweah, and Tule Groundwater Basins and Adjacent Highlands areas, Southern San Joaquin Valley, California: U.S. Geological Survey Fact Sheet 2017–3001, 4 p., http://dx.doi.org/10.3133/fs20173001.

  17. 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

  18. 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

  19. 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

  20. 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

  1. Groundwater quality in the Northern Atlantic Coastal Plain aquifer system, eastern United States

    USGS Publications Warehouse

    Lindsey, Bruce; Belitz, Kenneth

    2017-01-19

    Groundwater provides nearly 50 percent of the Nation’s drinking water. To help protect this vital resource, the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Project assesses groundwater quality in aquifers that are important sources of drinking water. The Northern Atlantic Coastal Plain aquifer system constitutes one of the important areas being evaluated. One or more inorganic constituents with human-health benchmarks were detected at high concentrations in about 15 percent of the study area and at moderate concentrations in about 17 percent. Organic constituents were not detected at high concentrations in the study area.

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

    USGS Publications Warehouse

    Wieczorek, Michael; 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

  3. 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.

  4. Variations in hydrostratigraphy and groundwater quality between major geomorphic units of the Western Ganges Delta plain, SW Bangladesh

    NASA Astrophysics Data System (ADS)

    Mahmud, Md. Ilias; Sultana, Sarmin; Hasan, M. Aziz; Ahmed, Kazi Matin

    2017-06-01

    Relationships among geomorphology, hydrostratigraphy, and groundwater quality with special emphasis on arsenic and salinity have been analyzed in the Bangladesh part of the Western Ganges Delta (WGD). On the basis of the presence of characteristic geomorphic features, the study area is divided into two geomorphic units: fluvial deltaic plain (FDP) and fluvio-tidal deltaic plain (FTDP). Lithostratigraphic sections demonstrate that FDP is composed predominately of sandy material whereas FTDP is characterized by alternation of sand and clay/silty clay material. Hydrostratigraphically, FDP is characterized as a single aquifer system, whereas FTDP is a complex multi-aquifer system. Spatial distributions of arsenic concentrations in groundwater reveal that elevated arsenic (>0.01 mg/l) occurs mostly in the FDP. Occurrences of high arsenic in deeper part of the aquifer system (>100 m) in the FDP, particularly in the south-western part, is probably due to the absence of any prominent impermeable layer between the shallow and deeper part of the aquifer system. Distributions of chloride concentrations show an increasing trend in groundwater salinity from north to south, i.e., from FDP to FTDP.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. Ground-Water Quality Data in the Santa Clara River Valley Study Unit, 2007: Results from the California GAMA Program

    USGS Publications Warehouse

    Montrella, Joseph; Belitz, Kenneth

    2009-01-01

    Ground-water quality in the approximately 460-square-mile Santa Clara River Valley study unit (SCRV) was investigated from April to June 2007 as part of the statewide Priority Basin project of the Ground-Water 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 ground water used for public water supplies within SCRV, and to facilitate a statistically consistent basis for comparing water quality throughout California. Fifty-seven ground-water samples were collected from 53 wells in Ventura and Los Angeles Counties. Forty-two wells were selected using a randomized grid-based method to provide statistical representation of the study area (grid wells). Eleven wells (understanding wells) were selected to further evaluate water chemistry in particular parts of the study area, and four depth-dependent ground-water samples were collected from one of the eleven understanding wells to help understand the relation between water chemistry and depth. The ground-water samples were analyzed for a large number of synthetic organic constituents (volatile organic compounds [VOC], pesticides and pesticide degradates, potential wastewater-indicator compounds, and pharmaceutical compounds), a constituent of special interest (perchlorate), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial constituents. Naturally occurring isotopes (tritium, carbon-13, carbon-14 [abundance], stable isotopes of hydrogen and oxygen in water, stable isotopes of nitrogen and oxygen in nitrate, chlorine-37, and bromine-81), and dissolved noble gases also were measured to help identify the source

  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. Laboratory Column Experiments for Sequential Treatment of Nitrate and Phosphate in Groundwater

    NASA Astrophysics Data System (ADS)

    Jeen, S. W.; Jin, T. U.; Ha, J. H.

    2016-12-01

    Nitrogen and phosphorous are known as primary nutrients to cause eutrophication in surface water. Considering surface water and groundwater interactions, reduction in nutrients load from groundwater to surface water may alleviate possible outbreak of eutrophication. In this study, laboratory column experiments were performed to sequentially treat nitrate and phosphate in groundwater. Two columns were set up: the first column was targeted to treat nitrate using organic carbon materials and the second column was to treat phosphate using basic oxygen furnace (BOF) slag. The two columns were then connected to sequentially treat the two nutrients. The results showed that 20 mg/L NO3-N was completely reduced within 40 cm distance at a flow velocity of 20 cm/day through microbial denitrification process. Small amounts of nitrite and ammonia were detected, but the majority of nitrate is considered to be transformed to nitrogen gas. Phosphate (10 mg/L as PO4-P) was rapidly removed within less than 5 cm distance by phosphate mineral (e.g., hydroxyapatite) precipitation due to increases in pH, alkalinity, and calcium concentrations. When the two columns were sequentially connected, the general performances were similar to those when each column was assessed separately. However, additional phosphate removal in the first column was observed, possibly due to adsorption of phosphate onto the organic carbon materials. This study shows that nitrate and phosphate in groundwater can be effectively treated through passive treatment systems, such as permeable reactive barriers (PRBs), and they can contribute to reduction in nutrients load to surface water.

  13. 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

  14. 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.

  15. Vulnerability of recently recharged groundwater in principal [corrected] aquifers of the United States to nitrate contamination.

    PubMed

    Gurdak, Jason J; Qi, Sharon L

    2012-06-05

    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.

  16. 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.

  17. 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.

  18. 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.

  19. Ground-water hydrology and simulation of ground-water flow at Operable Unit 3 and surrounding region, U.S. Naval Air Station, Jacksonville, Florida

    USGS Publications Warehouse

    Davis, J.H.

    1998-01-01

    The Naval Air Station, Jacksonville (herein referred to as the Station), occupies 3,800 acres adjacent to the St. Johns River in Duval County, Florida. Operable Unit 3 (OU3) occupies 134 acres on the eastern side of the Station and has been used for industrial and commercial purposes since World War II. Ground water contaminated by chlorinated organic compounds has been detected in the surficial aquifer at OU3. The U.S. Navy and U.S. Geological Survey (USGS) conducted a cooperative hydrologic study to evaluate the potential for ground water discharge to the neighboring St. Johns River. A ground-water flow model, previously developed for the area, was recalibrated for use in this study. At the Station, the surficial aquifer is exposed at land surface and forms the uppermost permeable unit. The aquifer ranges in thickness from 30 to 100 feet and consists of unconsolidated silty sands interbedded with local beds of clay. The low-permeability clays of the Hawthorn Group form the base of the aquifer. The USGS previously conducted a ground-water investigation at the Station that included the development and calibration of a 1-layer regional ground-water flow model. For this investigation, the regional model was recalibrated using additional data collected after the original calibration. The recalibrated model was then used to establish the boundaries for a smaller subregional model roughly centered on OU3. Within the subregional model, the surficial aquifer is composed of distinct upper and intermediate layers. The upper layer extends from land surface to a depth of approximately 15 feet below sea level; the intermediate layer extends from the upper layer down to the top of the Hawthorn Group. In the northern and central parts of OU3, the upper and intermediate layers are separated by a low-permeability clay layer. Horizontal hydraulic conductivities in the upper layer, determined from aquifer tests, range from 0.19 to 3.8 feet per day. The horizontal hydraulic

  20. Experiences with groundwater contamination

    SciTech Connect

    Not Available

    1984-01-01

    This book discusses developments in combating groundwater contamination. The papers include: Regulation of Groundwater; Utility Experiences Related to Existing and Proposed Drinking Water Regulations; Point-of-Use Treatment Technology to Control Organic and Inorganic Contamination; Hazardous Waste Disposal Practices and Groundwater Contamination; Reverse Osmosis Treatment to Control Inorganic and Volatile Organic Contamination; The Dilemma of New Wells Versus Treatment; Characteristics and Handling of Wastes From Groundwater Treatment Systems; and Removing Solvents to Restore Drinking Water at Darien, Connecticut.

  1. Advanced oxidation technologies for the treatment of contaminated groundwater. Book chapter

    SciTech Connect

    Lewis, N.M.; Topudurti, K.

    1994-01-01

    The paper presents information on two pilot-field applications of advanced oxidation technologies for contaminated groundwater with organics. The Ultrox technology was demonstrated in 1989 with the U.S. Environmental Protection Agency's Superfund Innovative Technology Evaluation (SITE) program at the Lorentz Barrel and Drum (LB D) site in San Jose, California. Peroxidation Systems technology was applied at the Old O-Field site located within the Aberdeen Proving Ground, in Maryland. The information presented includes a description of the technologies, factors affecting the technologies, and results from the two pilot-scale studies of the UV/oxidation treatment system applications.

  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. 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

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

    USGS Publications Warehouse

    Fram, Miranda S.; Belitz, Kenneth

    2007-01-01

    Ground-water quality in the approximately 1,800 square-mile Southern Sierra study unit (SOSA) was investigated in June 2006 as part of the Statewide Basin Assessment Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Statewide 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 Southern Sierra study was designed to provide a spatially unbiased assessment of raw ground-water quality within SOSA, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from fifty wells in Kern and Tulare Counties. Thirty-five of the wells were selected using a randomized grid-based method to provide statistical representation of the study area, and fifteen were selected to evaluate changes in water chemistry along ground-water flow paths. The ground-water samples were analyzed for a large number of synthetic organic constituents [volatile organic compounds (VOCs), pesticides and pesticide degradates, pharmaceutical compounds, and wastewater-indicator 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], radioactive constituents, and microbial indicators. Naturally occurring isotopes [tritium, and carbon-14, and stable isotopes of hydrogen and oxygen in water], 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 samples for matrix spikes) were collected for approximately one-eighth of the wells, and the results for these samples were used to evaluate the quality of the data for the ground-water samples. Assessment of the

  6. Ground-Water Quality Data in the San Francisco Bay Study Unit, 2007: Results from the California GAMA Program

    USGS Publications Warehouse

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

    2009-01-01

    Ground-water quality in the approximately 620-square-mile San Francisco Bay study unit (SFBAY) was investigated from April through June 2007 as part of the Priority Basin project of the Ground-Water 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 quality, as well as a statistically consistent basis for comparing water quality throughout California. Samples in SFBAY were collected from 79 wells in San Francisco, San Mateo, Santa Clara, Alameda, and Contra Costa Counties. Forty-three of the wells sampled were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells). Thirty-six wells were sampled to aid in evaluation of specific water-quality issues (understanding wells). The ground-water samples were analyzed for a large number of synthetic organic constituents (volatile organic compounds [VOC], pesticides and pesticide degradates, pharmaceutical compounds, and potential wastewater-indicator compounds), constituents of special interest (perchlorate and N-nitrosodimethylamine [NDMA]), naturally occurring inorganic constituents (nutrients, major and minor ions, trace elements, chloride and bromide isotopes, and uranium and strontium isotopes), radioactive constituents, and microbial indicators. Naturally occurring isotopes (tritium, carbon-14 isotopes, and stable isotopes of hydrogen, oxygen, nitrogen, boron, and carbon), and dissolved noble gases (noble gases were analyzed in collaboration with Lawrence Livermore National Laboratory) also were measured to help identify the source and age of the sampled ground water. Quality-control samples (blank samples

  7. 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.

  8. Groundwater quality in the Southeastern Coastal Plain aquifer system, southeastern United States

    USGS Publications Warehouse

    Barlow, Jeannie; Lindsey, Bruce; Belitz, Kenneth

    2017-01-19

    Groundwater provides nearly 50 percent of the Nation’s drinking water. To help protect this vital resource, the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Project assesses groundwater quality in aquifers that are important sources of drinking water. The Southeastern Coastal Plain aquifer system constitutes one of the important areas being evaluated. One or more inorganic constituents with human-health benchmarks were detected at high concentrations in about 6 percent of the study area and at moderate concentrations in about 13 percent. One or more organic constituents with human-health benchmarks were detected at moderate concentrations in about 3 percent of the study area.

  9. Groundwater quality in the Coastal Lowlands aquifer system, south-central United States

    USGS Publications Warehouse

    Barlow, Jeannie R.B.; Belitz, Kenneth

    2017-01-19

    Groundwater provides nearly 50 percent of the Nation’s drinking water. To help protect this vital resource, the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Project assesses groundwater quality in aquifers that are important sources of drinking water. The Coastal Lowlands aquifer system constitutes one of the important areas being evaluated. One or more inorganic constituents with human-health benchmarks were detected at high concentrations in about 12 percent of the study area and at moderate concentrations in about 18 percent. Organic constituents were not detected at high or moderate concentrations in the study area.

  10. Groundwater quality in the Basin and Range Basin-Fill Aquifers, southwestern United States

    USGS Publications Warehouse

    Musgrove, MaryLynn; Belitz, Kenneth

    2017-01-19

    Groundwater provides nearly 50 percent of the Nation’s drinking water. To help protect this vital resource, the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Project assesses groundwater quality in aquifers that are important sources of drinking water. The Basin and Range basin-fill aquifers constitute one of the important areas being evaluated. One or more inorganic constituents with human-health benchmarks were detected at high concentrations in about 20 percent of the study area and at moderate concentrations in about 49 percent. Organic constituents were not detected at high concentrations in the study area. One or more organic constituents with human-health benchmarks were detected at moderate concentrations in about 3 percent of the study area.

  11. Adsorption of arsenic from a Nova Scotia groundwater onto water treatment residual solids.

    PubMed

    Gibbons, Meaghan K; Gagnon, Graham A

    2010-11-01

    Water treatment residual solids were examined in batch adsorption and column adsorption experiments using a groundwater from Halifax Regional Municipality that had an average arsenic concentration of 43 μg/L (±4.2 μg/L) and a pH of 8.1. The residual solids studied in this paper were from five water treatment plants, four surface water treatment plants that utilized either alum, ferric, or lime in their treatment systems, and one iron removal plant. In batch adsorption experiments, iron-based residual solids and lime-based residual solids pre-formed similarly to GFH, a commercially-available adsorbent, while alum-based residual solids performed poorly. Langmuir isotherm modeling showed that ferric residuals had the highest adsorptive capacity for arsenic (Q(max) = 2230 mg/kg and 42,910 mg/kg), followed by GFH (Q(max) = 640 mg/kg), lime (Q(max) = 160 mg/kg) and alum (Q(max) = <1 mg/kg and 3 mg/kg). Similarly, the maximum arsenic removal was >93% for the ferric and lime residuals and GFH, while the maximum arsenic removal was <49% for the alum residuals under the same conditions. In a column adsorption experiment, ferric residual solids achieved arsenic removal of >26,000 bed volumes before breakthrough past 10 μg As/L, whereas the effluent arsenic concentration from the GFH column was under the method detection limit at 28,000 bed volumes. Overall, ferric and lime water treatment residuals were promising adsorbents for arsenic adsorption from the groundwater, and alum water treatment residuals did not achieve high levels of arsenic adsorption.

  12. 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

  13. 2015 Groundwater Monitoring Report Project Shoal Area: Subsurface Correction Unit 447

    SciTech Connect

    Findlay, Rick

    2016-04-01

    The Project Shoal Area in Nevada was the site of a 12-kiloton-yield 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. The corrective action strategy is currently focused on revising the site conceptual model (SCM) and evaluating the adequacy of the 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. Although 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 evaluation of the groundwater monitoring network will be conducted when water levels at the site have stabilized to the agreement of both the U.S. Department of Energy Office of Legacy Management and the Nevada Division of Environmental Protection.

  14. 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.

  15. 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

  16. 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...

  17. 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...

  18. 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...

  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. Ex situ treatment of N-nitrosodimethylamine (NDMA) in groundwater using a fluidized bed reactor.

    PubMed

    Webster, Todd S; Condee, Charles; Hatzinger, Paul B

    2013-02-01

    N-nitrosodimethylamine (NDMA) is a suspected human carcinogen that has traditionally been treated in water using ultraviolet irradiation (UV). The objective of this research was to examine the application of a laboratory-scale fluidized bed reactor (FBR) as an alternative technology for treating NDMA to part-per-trillion (ng/L) concentrations in groundwater. Previous studies have shown that the bacterium Rhodococcus ruber ENV425 is capable of cometabolizing NDMA during growth on propane as a primary substrate in batch culture (Fournier et al., 2009) and in a bench-scale membrane bioreactor (Hatzinger et al., 2011) to low ng/L concentrations. R. ruber ENV425 was inoculated into the FBR during this study. With a hydraulic residence time (HRT) of 20 min, the FBR was found to be an effective means to treat 10-20 μg/L of NDMA to effluent concentrations less than 100 ng/L. When the HRT was increased to 30 min and oxygen and propane addition rates were optimized, the FBR system demonstrated treatment of the NDMA to effluent concentrations of less than 10 ng/L. Short-term shutdowns and the presence of trichloroethene (TCE) at 6 μg/L as a co-contaminant had minimal effect on the treatment of NDMA in the FBR. The data suggest that the FBR technology can be a viable alternative to UV for removing NDMA from groundwater. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. 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

  2. Field evaluation of a granular activated carbon fluid-bed bioreactor for treatment of chlorobenzene in groundwater

    SciTech Connect

    Klecka, G.M.; McDaniel, S.G.; Wilson, P.S.

    1996-12-31

    Although granular activated carbon (GAC), fluidized-bed bioreactors have been used for treatment of groundwater containing readily biodegradable organic compounds, there is only limited experience with treatment of chlorinated organics found at many industrial sites. This paper describes a field evaluation of a GAC fluid-bed bioreactor operated at various chlorobenzene concentrations and organic loading rates over a 7-month period. Microorganisms used to seed the bioreactor were provided by activated sludge form the site, as well as indigenous chlorobenzene-degrading bacteria present in the groundwater. Removal efficiencies exceeding 99.99% were achieved at organic loading rates between 6 and 10 pounds of total oxygen demand (lb TOD) per 25 cubic feet per day. Influent chlorobenzene concentrations ranging form 100 to 170 ppm were consistently reduced to below the detection limit of 10 ppb. Economic evaluation indicates that groundwater treatment costs for the bioreactor were lower than other conventional technologies. 44 refs., 9 figs., 5 tabs.

  3. 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.

  4. 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

  5. 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

  6. Remediation of Explosives in Groundwater Using Zero-Valent Iron In Situ Treatment Wells

    DTIC Science & Technology

    2008-03-01

    Phase 1) ................................................................. 14 3.6.1 Groundwater Chemical Analysis ...27 5.2 Performance Confirmation Methods ...5.3 Data Analysis , Interpretation, and Evaluation ........................................................................ 29 5.3.1 Groundwater Pumping

  7. Groundwater flow, velocity, and age in a thick, fine-grained till unit in southeastern Wisconsin

    NASA Astrophysics Data System (ADS)

    Simpkins, W. W.; Bradbury, K. R.

    1992-03-01

    Piezometer nests were installed at study sites in each of five north-south-trending end moraines of the late Pleistocene Oak Creek Formation in southeastern Wisconsin. The formation is composed primarily of a fine-grained glacial diamicton (till) and laterally continuous and discontinuous, coarse-grained lake and meltwater stream sediment. It overlies the Silurian dolomite aquifer, which is a source of drinking water to rural areas. The average vertical linear velocity and age of ground water in the Oak Creek Formation were estimated by three methods: Darcy's Law, environmental isotopes including 3H, δ2H, δ18O, and 14C (dissolved inorganic carbon), and solute transport modeling of 18O. The F-1 and Metro sites in the Tinley moraine showed excellent agreement among the three estimates of vertical velocity and showed the lowest velocity values (0.3-0.5 cm year -1 downward), which suggests that diffusion controls vertical mass transport at these sites. Although the extrapolated maximum age of ground water is 35 000 years, ground water below 75 m at these sites is probably not older than 15 000 years, which is the maximum age of the formation. Estimates of velocity showed less agreement at study sites in the Lake Border moraine system to the east and ranged from about 0.2 to 20.7 cm year -1; maximum groundwater age could range from 213 to 6000 years. Higher and more variable velocities, perhaps owing to thinner and more heterogeneous sediment in these areas, suggest that diffusion may not dominate vertical mass transport. Heterogeneity and fractures may also promote the development of groundwater flow systems dominated by lateral flow. Because of the uncertainty about the nature of groundwater flow, velocity, and age in the formation east of the Tinley moraine, future waste-disposal activity in southeastern Wisconsin should be confined to the thickest parts of the Tinley moraine near the present F-1 and Metro sites.

  8. Groundwater flow, velocity, and age in a thick, fine-grained till unit in southeastern Wisconsin

    USGS Publications Warehouse

    Simpkins, W.W.; Bradbury, K.R.

    1992-01-01

    Piezometer nests were installed at study sites in each of five north-south-trending end moraines of the late Pleistocene Oak Creek Formation in southeastern Wisconsin. The formation is composed primarily of a fine-grained glacial diamicton (till) and laterally continuous and discontinuous, coarse-grained lake and meltwater stream sediment. It overlies the Silurian dolomite aquifer, which is a source of drinking water to rural areas. The average vertical linear velocity and age of ground water in the Oak Creek Formation were estimated by three methods: Darcy's Law, environmental isotopes including 3H, ??2H, ??18O, and 14C (dissolved inorganic carbon), and solute transport modeling of 18O. The F-1 and Metro sites in the Tinley moraine showed excellent agreement among the three estimates of vertical velocity and showed the lowest velocity values (0.3-0.5 cm year-1 downward), which suggests that diffusion controls vertical mass transport at these sites. Although the extrapolated maximum age of ground water is 35 000 years, ground water below 75 m at these sites is probably not older than 15 000 years, which is the maximum age of the formation. Estimates of velocity showed less agreement at study sites in the Lake Border moraine system to the east and ranged from about 0.2 to 20.7 cm year-1; maximum groundwater age could range from 213 to 6000 years. Higher and more variable velocities, perhaps owing to thinner and more heterogeneous sediment in these areas, suggest that diffusion may not dominate vertical mass transport. Heterogeneity and fractures may also promote the development of groundwater flow systems dominated by lateral flow. Because of the uncertainty about the nature of groundwater flow, velocity, and age in the formation east of the Tinley moraine, future waste-disposal activity in southeastern Wisconsin should be confined to the thickest parts of the Tinley moraine near the present F-1 and Metro sites. ?? 1992.

  9. Examining mechanisms of groundwater Hg(II) treatment by reactive materials: an EXAFS study.

    PubMed

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

    2011-12-15

    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(-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 Å, 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 Å were observed for Hg in Cu+S, ATP-a, and ATP-d treatments, suggesting the formation of Hg-S bonds.

  10. 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.

  11. 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.

  12. Using groundwater age distributions to understand changes in methyl tert-butyl ether (MtBE) concentrations in ambient groundwater, northeastern United States

    USGS Publications Warehouse

    Lindsey, Bruce; Ayotte, Joseph; Jurgens, Bryant; DeSimone, Leslie

    2017-01-01

    Temporal changes in methyl tert-butyl ether (MtBE) concentrations in groundwater were evaluated in the northeastern United States, an area of the nation with widespread low-level detections of MtBE based on a national survey of wells selected to represent ambient conditions. MtBE use in the U.S. peaked in 1999 and was largely discontinued by 2007. Six well networks, each representing specific areas and well types (monitoring or supply wells), were each sampled at 10 year intervals between 1996 and 2012. Concentrations were decreasing or unchanged in most wells as of 2012, with the exception of a small number of wells where concentrations continue to increase. Statistically significant increasing concentrations were found in one network sampled for the second time shortly after the peak of MtBE use, and decreasing concentrations were found in two networks sampled for the second time about 10 years after the peak of MtBE use. Simulated concentrations from convolutions of estimates for concentrations of MtBE in recharge water with age distributions from environmental tracer data correctly predicted the direction of MtBE concentration changes in about 65 percent of individual wells. The best matches between simulated and observed concentrations were found when simulating recharge concentrations that followed the pattern of national MtBE use. Some observations were matched better when recharge was modeled as a plume moving past the well from a spill at one point in time. Modeling and sample results showed that wells with young median ages and narrow age distributions responded more quickly to changes in the contaminant source than wells with older median ages and broad age distributions. Well depth and aquifer type affect these responses. Regardless of the timing of decontamination, all of these aquifers show high susceptibility for contamination by a highly soluble, persistent constituent.

  13. 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)

  14. 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).

  15. 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.

  16. Electrochemical treatment of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) in groundwater impacted by aqueous film forming foams (AFFFs).

    PubMed

    Schaefer, Charles E; Andaya, Christina; Urtiaga, Ana; McKenzie, Erica R; Higgins, Christopher P

    2015-09-15

    Laboratory experiments were performed to evaluate the use of electrochemical treatment for the decomposition of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), as well as other perfluoroalkyl acids (PFAAs), in aqueous film forming foam (AFFF)-impacted groundwater collected from a former firefighter training area and PFAA-spiked synthetic groundwater. Using a commercially-produced Ti/RuO2 anode in a divided electrochemical cell, PFOA and PFOS decomposition was evaluated as a function of current density (0-20 mA/cm(2)). Decomposition of both PFOA and PFOS increased with increasing current density, although the decomposition of PFOS did not increase as the current density was increased above 2.5 mA/cm(2). At a current density of 10 mA/cm(2), the first-order rate constants, normalized for current density and treatment volume, for electrochemical treatment of both PFOA and PFOS were 46 × 10(-5) and 70 × 10(-5) [(min(-1)) (mA/cm(2))(-1) (L)], respectively. Defluorination was confirmed for both PFOA and PFOS, with 58% and 98% recovery as fluoride, respectively (based upon the mass of PFOA and PFOS degraded). Treatment of other PFAAs present in the groundwater also was observed, with shorter chain PFAAs generally being more recalcitrant. Results highlight the potential for electrochemical treatment of PFAAs, particularly PFOA and PFOS, in AFFF-impacted groundwater. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. 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.

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

    SciTech Connect

    Hutton, Rick

    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.

  19. Numerical Groundwater-Flow Model of the Minnelusa and Madison Hydrogeologic Units in the Rapid City Area, South Dakota

    USGS Publications Warehouse

    Putnam, Larry D.; Long, Andrew J.

    2009-01-01

    The city of Rapid City and other water users in the Rapid City area obtain water supplies from the Minnelusa and Madison aquifers, which are contained in the Minnelusa and Madison hydrogeologic units. A numerical groundwater-flow model of the Minnelusa and Madison hydrogeologic units in the Rapid City area was developed to synthesize estimates of water-budget components and hydraulic properties, and to provide a tool to analyze the effect of additional stress on water-level altitudes within the aquifers and on discharge to springs. This report, prepared in cooperation with the city of Rapid City, documents a numerical groundwater-flow model of the Minnelusa and Madison hydrogeologic units for the 1,000-square-mile study area that includes Rapid City and the surrounding area. Water-table conditions generally exist in outcrop areas of the Minnelusa and Madison hydrogeologic units, which form generally concentric rings that surround the Precambrian core of the uplifted Black Hills. Confined conditions exist east of the water-table areas in the study area. The Minnelusa hydrogeologic unit is 375 to 800 feet (ft) thick in the study area with the more permeable upper part containing predominantly sandstone and the less permeable lower part containing more shale and limestone than the upper part. Shale units in the lower part generally impede flow between the Minnelusa hydrogeologic unit and the underlying Madison hydrogeologic unit; however, fracturing and weathering may result in hydraulic connections in some areas. The Madison hydrogeologic unit is composed of limestone and dolomite that is about 250 to 610 ft thick in the study area, and the upper part contains substantial secondary permeability from solution openings and fractures. Recharge to the Minnelusa and Madison hydrogeologic units is from streamflow loss where streams cross the outcrop and from infiltration of precipitation on the outcrops (areal recharge). MODFLOW-2000, a finite-difference groundwater

  20. 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.

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

    PubMed

    Squillace, Paul J; Scott, Jonathon C; Moran, Michael J; Nolan, B T; Kolpin, Dana W

    2002-05-01

    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 > or = 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 microg/L, with a median of 0.02 microg/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.

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. Treatment of Chlorinated Aliphatic Contamination of Groundwater by Horizontal Recirculation Wells and by Constructed Vertical Flow Wetlands

    DTIC Science & Technology

    2002-03-01

    term remediation at hundreds of sites across the Air Force. Complementary modeling and column studies examined the potential for controlling and...the treatment phase after pumping. Complementary modeling and column studies examined the potential for controlling and treating groundwater...possible by the highly chemically reducing environment created in the organic-rich wetland sediment. This dynamic and productive region

  8. EVALUATION OF DEMONSTRATED AND EMERGING TECHNOLOGIES FOR THE TREATMENT AND CLEAN-UP OF CONTAMINATED LAND AND GROUNDWATER

    EPA Science Inventory

    This article provides an overview of the Phase III Pilot Study on the Evaluation of Demonstrated and Emerging Technologies for Treatment and Clean Up of Contaminated Land and Groundwater. It also contains the key conclusions of the Pilot Study and recommendations for further act...

  9. EVALUATION OF DEMONSTRATED AND EMERGING TECHNOLOGIES FOR THE TREATMENT AND CLEAN-UP OF CONTAMINATED LAND AND GROUNDWATER

    EPA Science Inventory

    This article provides an overview of the Phase III Pilot Study on the Evaluation of Demonstrated and Emerging Technologies for Treatment and Clean Up of Contaminated Land and Groundwater. It also contains the key conclusions of the Pilot Study and recommendations for further act...

  10. 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

  11. Factors affecting groundwater quality in the Valley and Ridge aquifers, eastern United States, 1993-2002

    USGS Publications Warehouse

    Johnson, Gregory C.; Zimmerman, Tammy M.; Lindsey, Bruce D.; Gross, Eliza L.

    2011-01-01

    Chemical and microbiological analyses of water from 230 wells and 35 springs in the Valley and Ridge Physiographic Province, sampled between 1993 and 2002, indicated that bedrock type (carbonate or siliciclastic rock) and land use were dominant factors influencing groundwater quality across a region extending from northwestern Georgia to New Jersey. The analyses included naturally occurring compounds (major mineral ions and radon) and anthropogenic contaminants [pesticides and volatile organic compounds (VOCs)], and contaminants, such as nitrate and bacteria, which commonly increase as a result of human activities. Natural factors, such as topographic position and the mineral composition of underlying geology, act to produce basic physical and geochemical conditions in groundwater that are reflected in physical properties, such as pH, temperature, specific conductance, and alkalinity, and in chemical concentrations of dissolved oxygen, radon, and major mineral ions. Anthropogenic contaminants were most commonly found in water from wells and springs in carbonate-rock aquifers. Nitrate concentrations exceeded U.S. Environmental Protection Agency maximum contaminant levels in 12 percent of samples, most of which were from carbonate-rock aquifers. Escherichia coli (E. coli), pesticide, and VOC detection frequencies were significantly higher in samples from sites in carbonate-rock aquifers. Naturally occurring elements, such as radon, iron, and manganese, were found in higher concentrations in siliciclastic-rock aquifers. Radon levels exceeded the proposed maximum contaminant level of 300 picocuries per liter in 74 percent of the samples, which were evenly distributed between carbonate- and siliciclastic-rock aquifers. The land use in areas surrounding wells and springs was another significant explanatory variable for the occurrence of anthropogenic compounds. Nitrate and pesticide concentrations were highest in samples collected from sites in agricultural areas and

  12. 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.

  13. Treatment of Perchlorate-Contaminated Groundwater Using Highly Selective, Regenerable Ion-Exchange Technologies

    SciTech Connect

    Gu, Baohua; Brown, Gilbert M

    2007-01-01

    Treatment of perchlorate-contaminated water using highly selective, regenerable ion-exchange and perchlorate-destruction technologies was demonstrated at a field site in California. Four treatment and four regeneration cycles were carried out, and no significant deterioration of resin performance was noted in two years. The bifunctional resin (Purolite A-530E) treated about 37,000 empty bed volumes (BVs) of groundwater before a significant breakthrough of perchlorate occurred at an average flow rate of 150 gpm (or 1 BV/min) and a feed perchlorate concentration of about 860 g/L. Sorbed perchlorate (~20 kg) was quantitatively recovered by eluting with as little as 1 BV of the FeCl3-HCl regenerant solution. The eluted ClO4- was highly concentrated in the third quarter of the first BV of the regenerant solution with a concentration up to 100,000 mg/L. This concentrated effluent greatly facilitated subsequent perchlorate destruction or recovery by precipitation as KClO4 salts. High perchlorate destruction efficiency (92 V97%) was observed by reduction with FeCl2 in a thermo-reactor, which enabled recycling of the FeCl3-HCl regenerant solution, thereby minimizing the need to dispose of secondary wastes containing ClO4-. This study demonstrates that a combination of novel selective, regenerable ion-exchange and perchlorate-destruction and/or recovery technologies could potentially lead to enhanced treatment efficiency and minimized secondary waste production.

  14. 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)

  15. 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

  16. 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

  17. As(III) oxidation by MnO2 during groundwater treatment.

    PubMed

    Gude, J C J; Rietveld, L C; van Halem, D

    2017-03-15

    The top layer of natural rapid sand filtration was found to effectively oxidise arsenite (As(III)) in groundwater treatment. However, the oxidation pathway has not yet been identified. The aim of this study was to investigate whether naturally formed manganese oxide (MnO2), present on filter grains, could abiotically be responsible for As(III) oxidation in the top of a rapid sand filter. For this purpose As(III) oxidation with two MnO2 containing powders was investigated in aerobic water containing manganese(II) (Mn(II)), iron(II) (Fe(II)) and/or iron(III) (Fe(III)). The first MnO2 powder was a very pure - commercially available - natural MnO2 powder. The second originated from a filter sand coating, produced over 22 years in a rapid filter during aeration and filtration. Jar test experiments showed that both powders oxidised As(III). However, when applying the MnO2 in aerated, raw groundwater, As(III) removal was not enhanced compared to aeration alone. It was found that the presence of Fe(II)) and Mn(II) inhibited As(III) oxidation, as Fe(II) and Mn(II) adsorption and oxidation were preferred over As(III) on the MnO2 surface (at pH 7). Therefore it is concluded that just because MnO2 is present in a filter bed, it does not necessarily mean that MnO2 will be available to oxidise As(III). However, unlike Fe(II), the addition of Fe(III) did not hinder As(III) oxidation on the MnO2 surface; resulting in subsequent effective As(V) removal by the flocculating hydrous ferric oxides.

  18. 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.

  19. 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

  20. 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

  1. Superfund Record of Decision (EPA Region 6): United Nuclear Corporation, Mckinley County, New Mexico, ground-water operable unit (first remedial action) September 1988

    SciTech Connect

    Not Available

    1988-09-30

    The United Nuclear Corporation (UNC) site is located approximately 17 miles northeast of Gallup, New Mexico in McKinley County. The site operated as a State-licensed uranium mill facility from June 1977 to May 1982. It includes an ore-processing mill (about 25 acres) and an unlined tailings pond area (about 100 acres). In July 1979, approximately 23 million gallons of tailings and pond water were released to a nearby river as a result of a dam breach in the tailings pond area. The site damage was repaired; however, attention was focused on ground-water contamination resulting from tailings seepage. Nevertheless, the offsite migration of radionuclides and chemical constituents from uranium milling byproduct materials into the ground water, as well as to surface water and air, are still principal threats at the site. The remedial action will address onsite ground water contamination. Source control and onsite surface reclamation will be implemented under the direction of the Nuclear Regulatory Commission and integrated with this ground water operable unit. The primary contaminants of concern affecting the ground water are metals including arsenic, and radioactive substances including radium-226/228 and gross alpha. The selected remedial action for the site is included.

  2. 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.

  3. 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.

  4. 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.

  5. Vulnerability of shallow groundwater and drinking-water wells to nitrate in the United States.

    PubMed

    Nolan, Bernard T; Hitt, Kerie J

    2006-12-15

    Two nonlinear models were developed at the national scale to (1) predict contamination of shallow ground water (typically < 5 m deep) by nitrate from nonpoint sources and (2) to predict ambient nitrate concentration in deeper supplies used for drinking. The new models have several advantages over previous national-scale approaches. First, they predict nitrate concentration (rather than probability of occurrence), which can be directly compared with water-quality criteria. Second, the models share a mechanistic structure that segregates nitrogen (N) sources and physical factors that enhance or restrict nitrate transport and accumulation in ground water. Finally, data were spatially averaged to minimize small-scale variability so that the large-scale influences of N loading, climate, and aquifer characteristics could more readily be identified. Results indicate that areas with high N application, high water input, well-drained soils, fractured rocks or those with high effective porosity, and lack of attenuation processes have the highest predicted nitrate concentration. The shallow groundwater model (mean square error or MSE = 2.96) yielded a coefficient of determination (R(2)) of 0.801, indicating that much of the variation in nitrate concentration is explained by the model. Moderate to severe nitrate contamination is predicted to occur in the High Plains, northern Midwest, and selected other areas. The drinking-water model performed comparably (MSE = 2.00, R(2) = 0.767) and predicts that the number of users on private wells and residing in moderately contaminated areas (>5 to < or =10 mg/L nitrate) decreases by 12% when simulation depth increases from 10 to 50 m.

  6. Vulnerability of shallow groundwater and drinking-water wells to nitrate in the United States

    USGS Publications Warehouse

    Nolan, Bernard T.; Hitt, Kerie J.

    2006-01-01

    Two nonlinear models were developed at the national scale to (1) predict contamination of shallow ground water (typically < 5 m deep) by nitrate from nonpoint sources and (2) to predict ambient nitrate concentration in deeper supplies used for drinking. The new models have several advantages over previous national-scale approaches. First, they predict nitrate concentration (rather than probability of occurrence), which can be directly compared with water-quality criteria. Second, the models share a mechanistic structure that segregates nitrogen (N) sources and physical factors that enhance or restrict nitrate transport and accumulation in ground water. Finally, data were spatially averaged to minimize small-scale variability so that the large-scale influences of N loading, climate, and aquifer characteristics could more readily be identified. Results indicate that areas with high N application, high water input, well-drained soils, fractured rocks or those with high effective porosity, and lack of attenuation processes have the highest predicted nitrate concentration. The shallow groundwater model (mean square error or MSE = 2.96) yielded a coefficient of determination (R2) of 0.801, indicating that much of the variation in nitrate concentration is explained by the model. Moderate to severe nitrate contamination is predicted to occur in the High Plains, northern Midwest, and selected other areas. The drinking-water model performed comparably (MSE = 2.00, R2 = 0.767) and predicts that the number of users on private wells and residing in moderately contaminated areas (>5 to ≤10 mg/L nitrate) decreases by 12% when simulation depth increases from 10 to 50 m.

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. Annual drought flow and groundwater storage trends in the eastern half of the United States during the past two-third century

    NASA Astrophysics Data System (ADS)

    Brutsaert, Wilfried

    2010-03-01

    Low flow drainage from a river system, in the absence of precipitation or snowmelt, derives directly from the water stored in the upstream aquifers in the basin; therefore, observations of the trends of the annual lowest flows can serve to deduce quantitative estimates of the evolution of the basin-scale groundwater storage over the period of the streamflow record. Application of this method has allowed for the first time to determine the magnitudes of the trends in groundwater storage over the past two-third century in some 41 large prototypical basins in the United States east of the Rocky Mountains. It was found that during the period 1940-2007 groundwater storage has generally been increasing in most areas; these positive trends were especially pronounced in the Ohio and Upper Mississippi Water Resources Regions, but they were weaker in most other regions. Notable exceptions are the northern New England and especially the South Atlantic-Gulf regions, which saw prolonged declines in groundwater levels over this nearly 70-year long period. These observed long-term trends are generally in agreement with previous studies regarding trends of other components of the water cycle, such as precipitation, total runoff, and terrestrial evaporation. Over the most recent 20 years, from 1988 through 2007, except for the Ohio and the Souris-Red-Rainy regions, most regions have experienced declining average groundwater levels to varying degrees, with maximal values of the order of -0.2 mm a-1.

  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. Interactions of water quality and integrated groundwater management: Examples from the United States and Europe: Chapter 14

    USGS Publications Warehouse

    Warner, Kelly L.; Barataud, Fabienne; Hunt, Randall J.; Benoit, Marc; Anglade, Juliette; Borchardt, Mark A.

    2015-01-01

    Groundwater is available in many parts of the world, but the quality of the water may limit its use. Contaminants can limit the use of groundwater through concerns associated with human health, aquatic health, economic costs, or even societal perception. Given this broad range of concerns, this chapter focuses on examples of how water quality issues influence integrated groundwater management. One example evaluates the importance of a naturally occurring contaminant Arsenic (As) for drinking water supply, one explores issues resulting from agricultural activities on the land surface and factors that influence related groundwater management, and the last examines unique issues that result from human-introduced viral pathogens for groundwater-derived drinking water vulnerability. The examples underscore how integrated groundwater management lies at the intersections of environmental characterization, engineering constraints, societal needs, and human perception of acceptable water quality. As such, water quality factors can be a key driver for societal decision making.

  14. The electrocoagulation/advanced oxidation treatment of the groundwater used for human consumption.

    PubMed

    Orescanin, Visnja; Kollar, Robert; Nad, Karlo

    2011-01-01

    The purpose of this work was development and application of the purification system suitable for the treatment of groundwater used for human consumption, satisfying following criteria: (a) no need for external addition of the chemicals; (b) simultaneous removal of wide range of contaminants present in the treated water; (c) low sensitivity to the changes in the composition of the treated water; (d) high quality of treated water with regards to all measured parameters. Therefore the well water from the 60 m deep water layer situated near the city of Osijek (Eastern Croatia) with elevated values of heavy metals, color, turbidity, suspended solids, ammonia and organic contaminants was processed. Due to the complex composition of the treated water, the purification system required the combination of electroreduction/electrocoagulation, using iron and aluminum electrode plates followed by the simultaneous ozonation/UV treatment. The electroreduction/electrocoagulation approach was used for the removal of heavy metals, suspended solids, color and turbidity, while the organic contaminants and ammonia were removed by the ozonation/UV treatment. All measured parameters in the purified water were significantly lower compared to the regulated values. Under the optimum treatment conditions, the removal efficiencies for color, turbidity, nickel and arsenic were 100%. The removal efficiencies of V, Cr, Mn, Fe, Cu, Zn, Pb, ammonia, fluorides, sulfates and COD were 94.5%, 96.0%, 98.3%, 99.6%, 99.7%, 97.8%, 96.7%, 96,7%, 93.4%, 51.4%, 72.2% and 93.8%, respectively, increasing with the increased initial concentrations.

  15. 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

  16. 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...

  17. Alternative ponderosa pine restoration treatments in the western United States

    Treesearch

    James McIver; Phillip Weatherspoon; Carl Edminster

    2001-01-01

    Compared to presettlement times, many ponderosa pine forests of the United States are now more dense and have greater quantities of fuels. Widespread treatments are needed in these forests to restore ecological integrity and to reduce the risk of uncharacteristically severe fires. Among possible restorative treatments, however, the appropriate balance among cuttings,...

  18. 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...

  19. Enhanced nitrogen removal with an onsite aerobic cyclic biological treatment unit.

    PubMed

    Babcock, Roger W; Senthill, Atiim; Lamichhane, Krishna M; Agsalda, Jessica; Lindbo, Glen D

    2015-01-01

    Coastal Zone Act Reauthorization Amendments (CZARA, Section 6217) necessitate the requirement that onsite wastewater disposal units located near impaired surface waters or groundwater to provide at least 50% nitrogen removal. Approximately 38% of Hawaii households use onsite systems including septic tanks and cesspools that cannot meet this requirement. Upgrades to aerobic treatment units (ATUs) are a possible compliance solution. In Hawaii, ATUs must meet National Sanitation Foundation Standard 40 (NSF40) Class I effluent criteria. Previously, a multi-chamber, flow-through, combined attached/suspended growth type ATU (OESIS-750) and presently, a sequencing batch type ATU (CBT 0.8KF-210) were evaluated for NSF40 compliance, nutrient removal capability (NSF245), and adaptability for water reuse (NSF350). Both units easily achieved the NSF40 Class I effluent criteria. While the OESIS-750 achieved only 19% nitrogen removal, the CBT unit achieved 81% nitrogen removal, meeting the NSF245 criteria and CZARA requirements for applications in critical wastewater disposal areas. In addition, the CBT consistently produced effluent with turbidity less than 2 NTU (NSF350) and UVT254 greater than 70%, facilitating the production of unrestricted-use recycled water.

  20. 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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  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.; 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. 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.

  3. In Situ Catalytic Groundwater Treatment Using Pd-Catalysts and Horizontal Flow Treatment Wells

    DTIC Science & Technology

    2007-02-01

    35 Figure 4-4: HFTW System at Site 19 Edwards AFB (After McCarty et al., 1998)...................... 42 Figure 4-5: Simulated TCE Concentrations...constructed to simulate operation of an HFTW system at Site 19 Edwards AFB. The HFTW system consists of upflow and downflow treatment wells, with Pd...APPENDIX A Analytical Methods Supporting the Experimental Design An ASAP system was used to collect and process ground water samples for this

  4. 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.

  5. 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

  6. 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

  7. 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.

  8. 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.

  9. Online flow cytometry reveals microbial dynamics influenced by concurrent natural and operational events in groundwater used for drinking water treatment

    PubMed Central

    Besmer, Michael D.; Epting, Jannis; Page, Rebecca M.; Sigrist, Jürg A.; Huggenberger, Peter; Hammes, Frederik

    2016-01-01

    Detailed measurements of physical, chemical and biological dynamics in groundwater are key to understanding the important processes in place and their influence on water quality – particularly when used for drinking water. Measuring temporal bacterial dynamics at high frequency is challenging due to the limitations in automation of sampling and detection of the conventional, cultivation-based microbial methods. In this study, fully automated online flow cytometry was applied in a groundwater system for the first time in order to monitor microbial dynamics in a groundwater extraction well. Measurements of bacterial concentrations every 15 minutes during 14 days revealed both aperiodic and periodic dynamics that could not be detected previously, resulting in total cell concentration (TCC) fluctuations between 120 and 280 cells μL−1. The aperiodic dynamic was linked to river water contamination following precipitation events, while the (diurnal) periodic dynamic was attributed to changes in hydrological conditions as a consequence of intermittent groundwater extraction. Based on the high number of measurements, the two patterns could be disentangled and quantified separately. This study i) increases the understanding of system performance, ii) helps to optimize monitoring strategies, and iii) opens the possibility for more sophisticated (quantitative) microbial risk assessment of drinking water treatment systems. PMID:27924920

  10. 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.

  11. Online flow cytometry reveals microbial dynamics influenced by concurrent natural and operational events in groundwater used for drinking water treatment.

    PubMed

    Besmer, Michael D; Epting, Jannis; Page, Rebecca M; Sigrist, Jürg A; Huggenberger, Peter; Hammes, Frederik

    2016-12-07

    Detailed measurements of physical, chemical and biological dynamics in groundwater are key to understanding the important processes in place and their influence on water quality - particularly when used for drinking water. Measuring temporal bacterial dynamics at high frequency is challenging due to the limitations in automation of sampling and detection of the conventional, cultivation-based microbial methods. In this study, fully automated online flow cytometry was applied in a groundwater system for the first time in order to monitor microbial dynamics in a groundwater extraction well. Measurements of bacterial concentrations every 15 minutes during 14 days revealed both aperiodic and periodic dynamics that could not be detected previously, resulting in total cell concentration (TCC) fluctuations between 120 and 280 cells μL(-1). The aperiodic dynamic was linked to river water contamination following precipitation events, while the (diurnal) periodic dynamic was attributed to changes in hydrological conditions as a consequence of intermittent groundwater extraction. Based on the high number of measurements, the two patterns could be disentangled and quantified separately. This study i) increases the understanding of system performance, ii) helps to optimize monitoring strategies, and iii) opens the possibility for more sophisticated (quantitative) microbial risk assessment of drinking water treatment systems.

  12. Viruses in soil and groundwater

    SciTech Connect

    Vaughn, J.M.; Landry, E.F.

    1981-01-01

    Human viruses usually gain access to soil systems through intentional or unintentional discharges of domestic wastewater. Intentional land treatment/disposal systems represent an attractive alternative to surface water discharges, providing both economic and environmental advantages. Major concerns over the possible threat to human health as a result of the large-scale use of such systems are as yet unresolved. One such concern involves the potential for viral contamination of groundwater systems which currently supply the drinking-water needs of half the United States population. While no groundwater-borne disease outbreaks of viral etiology have as yet been associated with land treatment use, the potential for their occurrence has been clearly indicated by epidemiological studies of outbreaks associated with groundwater pollution from unintentional modes of soil application. Epidemiological evidence has been supported by an increasing number of field studies which have demonstrated viral contamination of shallow aquifers resulting from the use of various land treatment modes, such as rapid infiltration/recharge systems. More recent studies have indicated that soil-associated microbial pollution of groundwater may be abated by the use of systems management practices based upon an understanding of the physical and chemical factors which influence viral retention in soil including: temperature; pH; moisture, clay and ion content; depth to groundwater; infiltration rate; and soil continuity. The proper manipulation of these principles in the operation of land treatment schemes which utilize high-quality wastewater effluents should provide the means for significantly diminishing the likelihood of viral movement to groundwater systems.

  13. 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.

  14. 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.

  15. 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

  16. 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...

  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. 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

  19. An Analysis of Groundwater Flow Patterns in a Constructed Treatment Wetland Cell

    DTIC Science & Technology

    2008-03-01

    Difference Ground-Water Flow Model, more commonly referred to as MODFLOW . It was developed in the early 1980’s by the U.S. Geological Survey to... MODFLOW has been upgraded many times since then and in 1990s MODFLOW became the most widely used groundwater flow modeling suite. In MODFLOW 2000...hydraulic system to be simulated (Harbaugh, 2006). MODFLOW is a deterministic and numeric type of modeling suite using the finite differences method to

  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. 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

  2. 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.

  3. Status and understanding of groundwater quality in the North San Francisco Bay Shallow Aquifer study unit, 2012; California GAMA Priority Basin Project

    USGS Publications Warehouse

    Bennett, George L.

    2017-07-20

    Groundwater quality in the North San Francisco Bay Shallow Aquifer study unit (NSF-SA) was investigated as part of the Priority Basin Project of the California Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is in Marin, Mendocino, Napa, Solano, and Sonoma Counties and included two physiographic study areas: the Valleys and Plains area and the surrounding Highlands area. The NSF-SA focused on groundwater resources used for domestic drinking water supply, which generally correspond to shallower parts of aquifer systems than that of groundwater resources used for public drinking water supply in the same area. The assessments characterized the quality of untreated groundwater, not the quality of drinking water.This study included three components: (1) a status assessment, which characterized the status of the quality of the groundwater resources used for domestic supply for 2012; (2) an understanding assessment, which evaluated the natural and human factors potentially affecting water quality in those resources; and (3) a comparison between the groundwater resources used for domestic supply and those used for public supply.The status assessment was based on data collected from 71 sites sampled by the U.S. Geological Survey for the GAMA Priority Basin Project in 2012. To provide context, concentrations of constituents measured in groundwater were compared to U.S. Environmental Protection Agency (EPA) and California State Water Resources Control Board Division of Drinking Water regulatory and non-regulatory benchmarks for drinking-water quality. The status assessment used a grid-based method to estimate the proportion of the groundwater resources that has concentrations of water-quality constituents approaching or above benchmark concentrations. This method provides statistically unbiased results at the study-area scale and permits comparisons to other GAMA Priority Basin Project study areas.In the NSF-SA study unit as a whole, inorganic

  4. Monitor Unit Checking in Heterogeneous Stereotactic Body Radiotherapy Treatment Planning

    SciTech Connect

    Higgins, Patrick D.; Adolfson, Troy; Cho, L. Chinsoo; Saxena, Rishik

    2011-10-01

    Treatment of lung cancer using very-high-dose fractionation in small fields requires well-tested dose modeling, a method for density-averaging compound targets constructed from different parts of the breathing cycle, and monitor unit verification of the heterogeneity-corrected treatment plans. The quality and safety of each procedure are dependent on these factors. We have evaluated the dosimetry of our first 26 stereotactic body radiotherapy (SBRT) patients, including 260 treatment fields, planned with the Pinnacle treatment planning system. All targets were combined from full expiration and inspiration computed tomography scans and planned on the normal respiration scan with 6-MV photons. Combined GTVs (cGTVs) have been density-averaged in different ways for comparison of the effect on total monitor units. In addition, we have compared planned monitor units against hand calculations using 2 classic 1D correction methods: (1) effective attenuation and (2) ratio of Tissue-Maximum Ratios (TMRs) to determine the range of efficacy of simple verification methods over difficult-to-perform measurements. Different methods of density averaging for combined targets have been found to have minimal impact on total dose as evidenced by the range of total monitor units generated for each method. Nondensity-corrected treatment plans for the same fields were found to require about 8% more monitor units on average. Hand calculations, using the effective attenuation method were found to agree with Pinnacle calculations for nonproblematic fields to within {+-}10% for >95% of the fields tested. The ratio of TMRs method was found to be unacceptable. Reasonable choices for density-averaging of cGTVs using full inspiration/expiration scans should not strongly affect the planning dose. Verification of planned monitor units, as a check for problematic fields, can be done for 6-MV fields with simple 1D effective attenuation-corrected hand calculations.

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

    SciTech Connect

    Ruskauff, Greg

    2006-06-01

    A steady-state groundwater flow model of the Pahute Mesa Corrective Action Unit (CAU) has been constructed using a suite of hydrostratigraphic frameworks, recharge distributions, and hydraulic parameter assignment conceptualizations. Model calibration and sensitivity analyses, and geochemical verification were conducted and documented. The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office initiated the Underground Test Area Project to assess and evaluate the effects of the underground nuclear weapons tests on groundwater on the Nevada Test Site and vicinity through the Federal Facility Agreement and Consent Order (FFACO). The processes that will be used to complete Underground Test Area corrective actions are described in the "Corrective Action Strategy" in the FFACO Appendix VI, Rev. 1 (December 7, 2000). The objective of the strategy is to analyze and evaluate each Underground Test Area CAU through a combination of data and information collection and evaluation, and modeling groundwater flow and contaminant transport, including uncertainty. The FFACO corrective action process for the Central and Western Pahute Mesa CAUs was initiated with the Corrective Action Investigation Plan. This Corrective Action Investigation Plan identified a three-step model development process to evaluate the impact of testing on groundwater and simulate a contaminant boundary. The first step is the compilation and evaluation of existing and new data for use in the flow model and is documented in a series of data compilation and analysis reports, including Hydrologic Data for Groundwater Flow and Contaminant Transport Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nye County, Nevada. The second step is the development of the groundwater flow model, documented in this report. The third step is the development of the transport model to assess the migration of radionuclides away from underground nuclear test cavities on

  6. 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

  7. 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

  8. 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)

  9. 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.

  10. Groundwater-quality data for the Madera/Chowchilla–Kings shallow aquifer study unit, 2013–14: Results from the California GAMA Program

    USGS Publications Warehouse

    Shelton, Jennifer L.; Fram, Miranda S.

    2017-02-03

    Groundwater quality in the 2,390-square-mile Madera/Chowchilla–Kings Shallow Aquifer study unit was investigated by the U.S. Geological Survey from August 2013 to April 2014 as part of the California State Water Resources Control Board Groundwater Ambient Monitoring and Assessment Program’s Priority Basin Project. The study was designed to provide a statistically unbiased, spatially distributed assessment of untreated groundwater quality in the shallow aquifer systems of the Madera, Chowchilla, and Kings subbasins of the San Joaquin Valley groundwater basin. The shallow aquifer system corresponds to the part of the aquifer system generally used by domestic wells and is shallower than the part of the aquifer system generally used by public-supply wells. This report presents the data collected for the study and a brief preliminary description of the results.Groundwater samples were collected from 77 wells and were analyzed for organic constituents, inorganic constituents, selected isotopic and age-dating tracers, and microbial indicators. Most of the wells sampled for this study were private domestic wells. Unlike groundwater from public-supply wells, the groundwater from private domestic wells is not regulated for quality in California and is rarely analyzed for water-quality constituents. To provide context for the sampling results, however, concentrations of constituents measured in the untreated groundwater were compared with regulatory and non-regulatory benchmarks established for drinking-water quality by the U.S. Environmental Protection Agency, the State of California, and the U.S. Geological Survey.Of the 319 organic constituents assessed in this study (90 volatile organic compounds and 229 pesticides and pesticide degradates), 17 volatile organic compounds and 23 pesticides and pesticide degradates were detected in groundwater samples; concentrations of all but 2 were less than the respective benchmarks. The fumigants 1,2-dibromo-3-chloropropane (DBCP

  11. 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.

  12. 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.

  13. Beyond Ebola treatment units: severe infection temporary treatment units as an essential element of Ebola case management during an outbreak.

    PubMed

    Janke, Christian; Heim, Katrin Moira; Steiner, Florian; Massaquoi, Moses; Gbanya, Miatta Zenabu; Frey, Claudia; Froeschl, Guenter

    2017-02-06

    In the course of the Ebola outbreak in West Africa that was witnessed since early 2014, the response mechanisms showed deficits in terms of timeliness, volume and adequacy. The authors were deployed in the Ebola campaign in the West African country Liberia, where by September 2014 the changing epidemiological pattern made reconsiderations of guidelines and adopted procedures necessary. A temporary facility set up as a conventional Ebola Treatment Unit in the Liberian capital Monrovia was re-dedicated into a Severe Infections Temporary Treatment Unit. This facility allowed for stratification based on the nosocomial risk of exposure to Ebola virus for a growing subgroup of admitted patients that in the end would turn out as Ebola negative cases. At the same time, adequate diagnostic measures and treatment for the non-Ebola conditions of these patients could be provided without compromising work safety of the employed staff. The key elements of the new unit comprised a Suspect Cases Area similar to that of conventional Ebola treatment units for newly arriving patients, an Unlikely Cases Area for patients with a first negative Ebola PCR result, and a Confirmed Negative Cases Area for patients in whom Ebola could be ruled out. The authors, comprising representatives of the Liberian Ministry of Health and Social Welfare, as well as infectious disease specialists from the German Ebola Task Force are presenting key features of the adapted concept, and are highlighting its relevance in raising acceptance for outbreak counter-measures within the population at stake.

  14. Leishmaniasis in the United States: Treatment in 2012

    PubMed Central

    Murray, Henry W.

    2012-01-01

    Although civilian physicians in the United States seldom encounter patients with leishmaniasis, therapeutic advances in endemic regions have opened the door to approaches that can be applied in this country. Advances revolve around the use of oral miltefosine in all forms of leishmaniasis and the use of short-course intravenous liposomal amphotericin B in visceral and possibly cutaneous infection. Lengthy, traditional intravenous treatment with pentavalent antimony (sodium stibogluconate) still has a role in the United States; however, although expensive, miltefosine and liposomal amphotericin B are considerably more appealing selections for initial therapy. PMID:22403313

  15. Status and understanding of groundwater quality in the Bear Valley and Lake Arrowhead Watershed Study Unit, 2010: California GAMA Priority Basin Project

    USGS Publications Warehouse

    Mathany, Timothy; Burton, Carmen

    2017-06-20

    Groundwater quality in the 112-square-mile Bear Valley and Lake Arrowhead Watershed (BEAR) study unit was investigated as part of the Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit comprises two study areas (Bear Valley and Lake Arrowhead Watershed) in southern California in San Bernardino County. The GAMA-PBP is conducted by the California State Water Resources Control Board (SWRCB) in cooperation with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory.The GAMA BEAR study was designed to provide a spatially balanced, robust assessment of the quality of untreated (raw) groundwater from the primary aquifer systems in the two study areas of the BEAR study unit. The assessment is based on water-quality collected by the USGS from 38 sites (27 grid and 11 understanding) during 2010 and on water-quality data from the SWRCB-Division of Drinking Water (DDW) database. The primary aquifer system is defined by springs and the perforation intervals of wells listed in the SWRCB-DDW water-quality database for the BEAR study unit.This study included two types of assessments: (1) a status assessment, which characterized the status of the quality of the groundwater resource as of 2010 by using data from samples analyzed for volatile organic compounds, pesticides, and naturally present 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 BEAR study unit, not the treated drinking water delivered to consumers. Bear Valley study area and the Lake Arrowhead Watershed study area were also compared statistically on the basis of water-quality results and factors potentially affecting the groundwater quality.Relative concentrations (RCs

  16. 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.

  17. 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...

  18. 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...

  19. 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.

  20. 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...

  1. 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...

  2. Treatment of Chlorinated Solvents in Groundwater Beneath an Occupied Building at the Young-Rainey STAR Center, Pinellas, FL

    SciTech Connect

    Daniel, Joe; Surovchak, Scott; Tabor, Charles

    2016-03-01

    Groundwater contamination, consisting of two dissolved-phase plumes originating from chlorinated solvent source areas, in the southeastern portion of the Young- Rainey Star Center (also known as the Pinellas County, Florida, Site) in Largo, Florida, has migrated beyond the property boundary, beneath the roadways, and beneath adjacent properties to the south and east. Groundwater contamination will persist as long as the onsite contaminant source remains. The origin of the contamination appears to be multiple long-term point sources beneath Building 100, a 4.5 ha (11 acre) building that housed manufacturing facilities during US DOE operations at the site. The site is now owned by Pinellas County, and most of the space inside the building is leased to private companies, so DOE chose not to conduct characterization or remediation through the floor of the building, instead choosing to conduct all work from outside the building. Injection of emulsified soybean oil and a microbial culture has been used at other areas of the site to accelerate naturally occurring bacterial processes that degrade groundwater contaminants to harmless compounds, and that same approach was chosen for this task. The technical approach consisted of installing horizontal wells from outside the building footprint, extending through and around the identified subsurface treatment areas, and terminating beneath the building. Two 107 m (350 ft) long wells, two 122 m (400 ft) long wells, and four 137 m (450 ft) long wells have been installed to intersect the inferred source areas and confirmed contaminant plumes beneath the building. DOE then injected emulsified vegetable oil and a microbial culture into the horizontal wells at each of several target areas beneath the building where the highest groundwater contaminant concentrations have been detected. The target areas are the northwest corner of the building between the old drum storage pad locations and monitoring well PIN12-S35B, the vicinity of

  3. Stable isotope compositions of waters in the Great Basin, United States 3. Comparison of groundwaters with modern precipitation

    USGS Publications Warehouse

    Smith, G.I.; Friedman, I.; Veronda, G.; Johnson, C.A.

    2002-01-01

    Groundwater samples from wells and springs, scattered over most of the Great Basin province, were collected and analyzed for their isotopic makeup. They were augmented by previously published isotopic data on groundwaters from southeast California and by several hundred unpublished isotopic analyses. The ratio of 2H (deuterium, D) to 1H, in water samples from valleys in parts of California, Idaho, Nevada, Oregon, and Utah, are here compared with the winter, summer, and annual isotopic compositions of precipitation falling in or near the sampled areas. The main goal of this study was to identify basins where the groundwaters have isotopic compositions that are "lighter" (depleted in the heavier isotope, D) relative to modern winter precipitation. Where these basins do not adjoin substantially higher terrain, we consider those light groundwaters to be of Pleistocene age and thus more than 10,000 years old. Where the groundwater is 10 to 19??? lighter than local winter precipitation, we consider it to be possibly an indication of Pleistocene water; where the ??D makeup is >20??? lighter, we consider it to be probably Pleistocene water. More than 80 sites underlain by waters of possible or probable Pleistocene age were identified.

  4. Simulation of ground-water flow in the lower sand unit of the Potomac-Raritan-Magothy aquifer system, Philadelphia, Pennsylvania

    USGS Publications Warehouse

    Sloto, R.A.

    1988-01-01

    Ground-water flow in the lower sand unit of the Potomac-Raritan-Magothy aquifer system in Philadelphia was simulated with a two-dimensional finite- difference ground-water model. The modeled 133-square-mile area also included parts of Delaware County, Pennsylvania, and Camden and Gloucester Counties, New Jersey. The lower sand unit is Cretaceous in age and consists of well- sorted coarse sand and fine gravel that grades upward into medium to fine sand containing a few thin beds of clay. The modeled aquifer consists of the lower sand unit in Philadelphia and the lowermost sand unit of the Potomac-Raritan-Magothy aquifer system in New Jersey. Throughout most of the area, the lower sand unit is overlain by a clay confining unit. Where the clay is absent, the lower sand unit is unconfined. A hydraulic conductivity of 1.6 x 10-3 foot per second and a storage coefficient of 3.0 x 10-4 was assigned to the lower sand unit based on 15 aquifer tests, and a hydraulic conductivity of 4.0 x 10-8 foot per second was assigned to the upper confining unit based on transient-flow sensitivity analysis. Water levels were not sensitive to changes in the value for specific storage of the upper confining unit, indicating that most vertical leakage occurs as steady leakage. Changes in the potentiometric surface of the lower sand unit for 1904-78 simulated. Differences between simulated and observed head generally were less than 10 feet. Simulations were made to determine the effects on hydraulic head of increases in industrial pumpage of 5 and 10 Mgal/d (million gallons per day) and of an emergency 60 Mgal/d municipal water supply in Philadelphia. A 5- and 10-Mgal/d increase in industrial pumpage would lower heads in the lower sand unit by as much as 33 and 66 feet, respectively. Pumping 60 Mgal/d for 30 days for an emergency municipal supply would lower heads in the lower sand unit by as much as 121 feet.

  5. 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.

  6. 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

    2017-03-01

    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

  7. 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

  8. 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

  9. 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

    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

  10. Transsexual legal rights in the United States and United kingdom: employment, medical treatment, and civil status.

    PubMed

    Green, Richard

    2010-02-01

    Whereas hormonal and surgical sex change have been increasingly refined and accepted medically during the past 40 years, legal protections have only recently received attention. This overview focuses on employment, medical treatment, and civil status as male or female in the United States and the United Kingdom. Employment protection in the UK is assured since a court decision in 1994, but in the U.S. is generally uncertain and inconsistent between states. Health care, including surgery, under the UK National Health Service, is assured since a court decision in 1996. In the U.S., the absence of a national insurance program and the reluctance of private insurers to fund treatment remains an obstacle. Military personnel and prisoners are provided treatment in the UK but there is no military-provided treatment in the U.S. and prison treatment is limited. Change in birth certificate sex status is available in the UK since 2004. This permits heterosexual marriage as a person of the reassigned sex. In the U.S., whereas nearly all states permit birth certificate modification, obstacles remain to recognition across state jurisdictions. Some states forbid marriage for a transsexual as a person of their reassigned sex. This can impact on transsexuals as parents.

  11. Technico-economic assessment of groundwater treatment by palladium-on-zeolite-catalyst in comparison to GAC fixed bed adsorbers.

    PubMed

    Bayer, P; Schüth, C

    2010-01-01

    A technico-economic comparison between palladium-on-zeolite (Pd/Y), and granular activated carbon (GAC) based methods of groundwater clean-up is presented. The treatment concepts are assessed by means of process-based cost functions that can be applied to a broad range of case-specific conditions. The analysis accounts for variability in cost and performance parameters and reduces the interplay of multiple factors to expressive indifference curves that can be used for identifying a favorable technology. The findings for the treatment of halogenated hydrocarbons reveal that the Pd/Y offers advantages compared to GAC use in case of high contaminant concentrations and for the treatment of lower halogenated compounds such as cis-Dichloroethene.

  12. Geohydrology of Storage Unit III and a combined flow model of the Santa Barbara and foothill ground-water basins, Santa Barbara County, California

    USGS Publications Warehouse

    Freckleton, John R.; Martin, Peter; Nishikawa, Tracy

    1998-01-01

    The city of Santa Barbara pumps most of its ground water from the Santa Barbara and Foothill ground-water basins. The Santa Barbara basin is subdivided into two storage units: Storage Unit I and Storage Unit III. The Foothill basin and Storage Unit I of the Santa Barbara basin have been studied extensively and ground-water flow models have been developed for them. In this report, the geohydrology of the Santa Barbara ground- water basin is described with a special emphasis on Storage Unit III in the southwestern part of the basin. The purposes of this study were to summarize and evaluate the geohydrology of Storage Unit III and to develop an areawide model of the Santa Barbara and Foothill basins that includes the previously unmodeled Storage Unit III. Storage Unit III is in the southwestern part of the city of Santa Barbara. It is approximately 3.5 miles long and varies in width from about 2,000 feet in the southeast to 4,000 feet in the north-west. Storage Unit III is composed of the Santa Barbara Formation and overlying alluvium. The Santa Barbara Formation (the principal aquifer) consists of Pleistocene and Pliocene(?) unconsolidated marine sand, silt, and clay, and it has a maximum saturated thickness of about 160 feet. The alluvium that overlies the Santa Barbara Formation has a maximum saturated thickness of about 140 feet. The storage unit is bounded areally by faults and low-permeability deposits and is underlain by rocks of Tertiary age. The main sources of recharge to Storage Unit III are seepage from Arroyo Burro and infiltration of precipitation. Most of the recharge occurs in the northwest part of the storage unit, and ground water flows toward the southeast along the unit's long axis. Lesser amounts of recharge may occur as subsurface flow from the Hope Ranch subbasin and as upwelling from the underlying Tertiary rocks. Discharge from Storage Unit III occurs as pumpage, flow to underground drains, underflow through alluvium in the vicinity of Arroyo

  13. 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

  14. 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

  15. Status and understanding of groundwater quality in the Northern Coast Ranges study unit, 2009: California GAMA Priority Basin Project

    USGS Publications Warehouse

    Mathany, Timothy M.; Belitz, Kenneth

    2015-01-01

    Chloroform, simazine, and perchlorate were observed in the Interior Basins and Coastal Basins study areas, predominantly at shallow sites with top-of-perforation depths ≤70 feet below land surface, with modern water (post-1950s), and with oxic groundwater conditions.

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

    Treesearch

    Daniel R. Hitckcock; Christopher D. Barton; Karin T. Rebel; Julian Singer; John C. Seanman; J. Dan Strawbridge; Susan J. Riha; John I. Blake

    2005-01-01

    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 Fourmile 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...

  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. 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...

  19. 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.

  20. Drinking-water treatment, climate change, and childhood gastrointestinal illness projections for northern Wisconsin (USA) communities drinking untreated groundwater

    NASA Astrophysics Data System (ADS)

    Uejio, Christopher K.; Christenson, Megan; Moran, Colleen; Gorelick, Mark

    2017-01-01

    This study examined the relative importance of climate change and drinking-water treatment for gastrointestinal illness incidence in children (age <5 years) from period 2046-2065 compared to 1991-2010. The northern Wisconsin (USA) study focused on municipalities distributing untreated groundwater. A time-series analysis first quantified the observed (1991-2010) precipitation and gastrointestinal illness associations after controlling for seasonality and temporal trends. Precipitation likely transported pathogens into drinking-water sources or into leaking water-distribution networks. Building on observed relationships, the second analysis projected how climate change and drinking-water treatment installation may alter gastrointestinal illness incidence. Future precipitation values were modeled by 13 global climate models and three greenhouse-gas emissions levels. The second analysis was rerun using three pathways: (1) only climate change, (2) climate change and the same slow pace of treatment installation observed over 1991-2010, and (3) climate change and the rapid rate of installation observed over 2011-2016. The results illustrate the risks that climate change presents to small rural groundwater municipalities without drinking water treatment. Climate-change-related seasonal precipitation changes will marginally increase the gastrointestinal illness incidence rate (mean: ˜1.5%, range: -3.6-4.3%). A slow pace of treatment installation somewhat decreased precipitation-associated gastrointestinal illness incidence (mean: ˜3.0%, range: 0.2-7.8%) in spite of climate change. The rapid treatment installation rate largely decreases the gastrointestinal illness incidence (mean: ˜82.0%, range: 82.0-83.0%).

  1. Drinking-water treatment, climate change, and childhood gastrointestinal illness projections for northern Wisconsin (USA) communities drinking untreated groundwater

    NASA Astrophysics Data System (ADS)

    Uejio, Christopher K.; Christenson, Megan; Moran, Colleen; Gorelick, Mark

    2017-06-01

    This study examined the relative importance of climate change and drinking-water treatment for gastrointestinal illness incidence in children (age <5 years) from period 2046-2065 compared to 1991-2010. The northern Wisconsin (USA) study focused on municipalities distributing untreated groundwater. A time-series analysis first quantified the observed (1991-2010) precipitation and gastrointestinal illness associations after controlling for seasonality and temporal trends. Precipitation likely transported pathogens into drinking-water sources or into leaking water-distribution networks. Building on observed relationships, the second analysis projected how climate change and drinking-water treatment installation may alter gastrointestinal illness incidence. Future precipitation values were modeled by 13 global climate models and three greenhouse-gas emissions levels. The second analysis was rerun using three pathways: (1) only climate change, (2) climate change and the same slow pace of treatment installation observed over 1991-2010, and (3) climate change and the rapid rate of installation observed over 2011-2016. The results illustrate the risks that climate change presents to small rural groundwater municipalities without drinking water treatment. Climate-change-related seasonal precipitation changes will marginally increase the gastrointestinal illness incidence rate (mean: ˜1.5%, range: -3.6-4.3%). A slow pace of treatment installation somewhat decreased precipitation-associated gastrointestinal illness incidence (mean: ˜3.0%, range: 0.2-7.8%) in spite of climate change. The rapid treatment installation rate largely decreases the gastrointestinal illness incidence (mean: ˜82.0%, range: 82.0-83.0%).

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

    NASA Astrophysics Data System (ADS)

    Webb, Robert H.; Leake, Stanley A.

    2006-04-01

    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. 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.

  4. Treatment of co-mingled benzene, toluene and TCE in groundwater.

    PubMed

    Chen, Liang; Liu, Yulong; Liu, Fei; Jin, Song

    2014-06-30

    This work addressed a hypothetical but practical scenario that includes biological oxidation and reductive dechlorination in treating groundwater containing co-mingled plume of trichloroethene (TCE), benzene and toluene. Groundwater immediately downgradient from the commonly used zero-valent iron (ZVI) has shown alkaline pH (up to 10.7). The elevated pH may influence BTEX compounds (i.e., benzene, toluene, ethyl benzene, and xylenes) biodegradation, which could also be inhibited by elevated concentrations of TCE. Data from this work suggests that the inhibition coefficients (IC) value for 100 μg/L and 500 μg/L of TCE on benzene and toluene degradation are 2.1-2.8 at pH 7.9, and 3.5-6.1 at pH 10.5. For a co-mingled plume, it appears to be more effective to reduce TCE by ZVI before addressing benzene and toluene biodegradation. The ample buffering capacity of most groundwater and the adaptation of benzene and toluene-degrading microbes are likely able to eliminate the adverse influence of pH shifts downgradient from a ZVI-PRB. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. 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.

  6. 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.

  7. Groundwater pollution microbiology

    SciTech Connect

    Bitton, G.; Gerba, C.P.

    1984-01-01

    This book provides a survey of available information on groundwater pollution microbiology. It is useful as a starting point for students and professionals investigating this topic. Subjects discussed include bacteria and virus movement through soils, carcinogenicity of some organic chemicals detected in groundwater, sampling techniques, and land treatment systems. Include references to the journal literature and a subject index.

  8. 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.

  9. 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

  10. 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

  11. 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

  12. 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

  13. Ground-water quality in three urban areas in the Coastal Plain of the southeastern United States, 1995

    USGS Publications Warehouse

    Berndt, M.P.; Galeone, D.R.; Spruill, T.B.; Crandall, C.A.

    1998-01-01

    Ground-water quality is generally good in three urban areas studied in the Coastal Plain of the southeastern United States?Ocala and Tampa, Florida, and Virginia Beach, Virginia. The hydrology of these areas differs in that Ocala has many karst depressions but virtually no surface-water features, and Tampa and Virginia Beach have numerous surface-water features, including small lakes, streams, and swamps. Samples were collected in early 1995 from 15 wells in Ocala (8 in the surficial aquifer and 7 in the Upper Floridan aquifer), 17 wells in Tamps (8 in the surficial aquifer and 9 in the Upper Floridan aquifer), and in the summer of 1995 from 15 wells in Virginia Beach (all in the surficial aquifer). In the surficial aquifer in Ocala, the major ion water type was calcium bicarbonate in five samples and mixed (no dominant ions) in three samples, with dissolved-solids concentrations ranging from 78 to 463 milligrams per liter. In Tampa, the water type was calcium bicarbonate in one sample and mixed in seven samples, with dissolved-solids concentrations ranging from 38 to 397 milligrams per liter. In Virginia Beach, water types were primarily calcium and sodium bicarbonate water, with dissolved-solids concentrations ranging from 89 to 740 milligrams per liter. The water types and dissolved-solids concentrations reflect the presence of carbonates in the surficial aquifer materials in the Ocala and Virginia Beach areas. The major ion water type was calcium bicarbonate for all 16 samples from the upper Floridan aquifer in both Florida cities. Dissolved-solids concentrations ranged from 210 to 551 milligrams per liter in Ocala, with a median of 287 milligrams per liter, and from 187 to 362 milligrams per liter in Tampa, with a median of 244 milligrams per liter. Concentrations of nitrate nitrogen were highest in the surficial aquifer in Ocala, and one sample exceeded 10 milligrams per liter, the U.S. Environmental Protection Agency maximum contaminant level for drinking

  14. 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; 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).

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

    MedlinePlus

    ... Cats Reported in the United States, 2008 Rabid Dogs Reported in the United States, 2008 Rabid Cattle ... Reported in the United States during 2009 Rabid Dogs Reported in the United States during 2009 Rabid ...

  16. Groundwater quality in the Valley and Ridge and Piedmont and Blue Ridge carbonate-rock aquifers, eastern United States

    USGS Publications Warehouse

    Lindsey, Bruce; Belitz, Kenneth

    2017-01-19

    Groundwater provides nearly 50 percent of the Nation’s drinking water. To help protect this vital resource, the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Project assesses groundwater quality in aquifers that are important sources of drinking water. The Valley and Ridge and Piedmont and Blue Ridge carbonate-rock aquifers constitute two of the important areas being evaluated. One or more inorganic constituents with human-health benchmarks were detected at high concentrations in about 15 percent of the study area and at moderate concentrations in about 17 percent. Organic constituents were not detected at high concentrations in the study area. One or more organic constituents with human-health benchmarks were detected at moderate concentrations in about 2 percent of the study area.

  17. Report for Full-Scale Mulch Wall Treatment of Chlorinated Hydrocarbon-Impacted Groundwater

    DTIC Science & Technology

    2006-05-31

    MW-33S MW-34S MW-31S MW-32S B301-MP5S ND B301- MP6S 1.2 SB9 SB7 SB3 SB5 SB2 HP4 SB1 HP1 A’ A MW-30S MW-27S 4/13/04 FULL-SCALE MULCH WALL Site B... MP6S 1.2 SB9 SB7 SB3 SB5 SB2 HP4 SB1 HP1 A’ A MW-30S MW-27S INSET MAP N Inset Scale (ft) 500 10000 Groundwater Flow 4 in steel gas main 24 in CMP

  18. 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

  19. Operable Unit 3-14, Tank Farm Soil and INTEC Groundwater Remedial Design/Remedial Action Scope of Work

    SciTech Connect

    D. E. Shanklin

    2007-07-25

    This Remedial Design/Remedial Action (RD/RA) Scope of Work pertains to OU 3-14 Idaho Nuclear Technology and Engineering Center and the Idaho National Laboratory and identifies the remediation strategy, project scope, schedule, and budget that implement the tank farm soil and groundwater remediation, in accordance with the May 2007 Record of Decision. Specifically, this RD/RA Scope of Work identifies and defines the remedial action approach and the plan for preparing the remedial design documents.

  20. 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. Published by Elsevier B.V.

  1. 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.

  2. Field Testing of Bimetallic Nanoscale Particle Technology for In-Situ Groundwater Treatment of a Fractured Rock DNAPL Zone

    NASA Astrophysics Data System (ADS)

    Zhang, W.; Walata, L.; Nash, R.; Gheorghiu, F.; Glazier, R.; Venkatakrishnan, R.

    2003-04-01

    This study has been carried out as part of the Corrective Measure Study (CMS) at a property owned by GlaxoSmithKline in Research Triangle Park, North Carolina, USA. The study area is located in the Durham subbasin of the Deep River Triassic Basin and is underlain by interbedded siltstone and sandstone sequences. Groundwater underlying portions of the site has been impacted by historical industrial activities conducted by previous owners; groundwater contaminants consist mainly of chlorinated volatile organic compounds. Golder conducted an initial review of potentially applicable remediation technologies and retained the Bimetallic Nanoscale Particle (BNP) technology for further evaluation. BNP consists of nanoscale particles (~ 60 nm) of zero valent iron (Fe0) with a trace coating of noble metal catalyst (palladium). The rapid destruction of a wide range of recalcitrant contaminants is based on a surface-catalyzed redox process where the contaminant serves as an electron acceptor and BNP as the electron donor and can be accomplished either in situ or ex situ (Wei-xian Zhang, 1997, 1999, 2000). This study presents the field demonstration of the BNP effectiveness to treat in-situ chlorinated VOCs in a complex fractured bedrock aquifer setting. During the field pilot test 11 kilograms of BNP mixed in water-based slurry were injected into the shallow bedrock groundwater suspected to contain dense non-aqueous phase liquids (DNAPLs). The results of the test indicated rapid treatment of chlorinated VOCs 7 m to 14 m around the injection well. In addition, the oxidation-reduction potential (ORP) and dissolved oxygen (DO) values have decreased and persisted at very low levels of -450 millivolts and less than 0.001 milligrams per liter, respectively, indicating favorable conditions for reductive dechlorination. Interpretation of pre- and post-test data on the in-situ microbiological community in the test area indicate that the changes in ORP and DO have resulted in inhibition

  3. Ground-Water Quality Data in the Owens and Indian Wells Valleys Study Unit, 2006: Results from the California GAMA Program

    USGS Publications Warehouse

    Densmore, Jill N.; Fram, Miranda S.; Belitz, Kenneth

    2009-01-01

    Ground-water quality in the approximately 1,630 square-mile Owens and Indian Wells Valleys study unit (OWENS) was investigated in September-December 2006 as part of the Priority Basin Project of 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 collaboration with the California State Water Resources Control Board (SWRCB). The Owens and Indian Wells Valleys study was designed to provide a spatially unbiased assessment of raw ground-water quality within OWENS study unit, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 74 wells in Inyo, Kern, Mono, and San Bernardino Counties. Fifty-three of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study area (grid wells), and 21 wells were selected to evaluate changes in water chemistry in areas of interest (understanding wells). The ground-water samples were analyzed for a large number of synthetic organic constituents [volatile organic compounds (VOCs), pesticides and pesticide degradates, pharmaceutical compounds, and potential wastewater- indicator 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], radioactive constituents, and microbial indicators. Naturally occurring isotopes [tritium, and carbon-14, and stable isotopes of hydrogen and oxygen in water], and dissolved noble gases also were measured to help identify the source and age of the sampled ground water. This study evaluated the quality of raw ground water in the aquifer in the OWENS study unit and did not attempt to evaluate the quality of treated water

  4. Combining ground-based and airborne EM through Artificial Neural Networks for modelling hydrogeological units under saline groundwater conditions

    NASA Astrophysics Data System (ADS)

    Gunnink, J. L.; Bosch, J. H. A.; Siemon, B.; Roth, B.; Auken, E.

    2012-03-01

    Airborne Electro Magnetic (EM) methods supply data over large areas in a cost-effective way. We used Artificial Neural Networks (ANN) to classify the geophysical signal into a meaningful geological parameter. By using examples of known relations between ground-based geophysical data (in this case electrical conductivity, EC, from Electrical Cone Penetration Tests) and geological parameters (presence of glacial till), we extracted learning rules that could be applied to map the presence of a glacial till using the EC profiles from the airborne EM data. The saline groundwater in the area was obscuring the EC signal from the till but by using ANN we were able to extract subtle and often non-linear, relations in EC that were representative for the presence of the till. The ANN results were interpreted as the probability of having till and showed a good agreement with drilling data. The glacial till is acting as a layer that inhibits groundwater flow, due to its high clay-content, and is therefore an important layer in hydrogeological modelling and for predicting the effects of climate change on groundwater quantity and quality.

  5. Treatment of four psychiatric emergencies in the intensive care unit.

    PubMed

    Bienvenu, O Joseph; Neufeld, Karin J; Needham, Dale M

    2012-09-01

    To review the diagnosis and management of four selected psychiatric emergencies in the intensive care unit: agitated delirium, neuroleptic malignant syndrome, serotonin syndrome, and psychiatric medication overdose. Review of relevant medical literature. Standardized screening for delirium should be routine. Agitated delirium should be managed with an antipsychotic and, possibly, dexmedetomidine in treatment-refractory cases. Delirium management should also include ensuring a calming environment and adequate pain control, minimizing benzodiazepines and anticholinergics, normalizing the sleep-wake cycle, providing sensory aids as required, and providing early physical and occupational therapy. Neuroleptic malignant syndrome should be treated by discontinuing dopamine blockers, providing supportive therapy, and possibly administering medications (benzodiazepines, dopamine agonists, and/or dantrolene) or electroconvulsive therapy, if indicated. Serotonin syndrome should be treated by discontinuing all serotonergic agents, providing supportive therapy, controlling agitation with benzodiazepines, and possibly administering serotonin2A antagonists. It is often unnecessary to restart psychiatric medications upon which a patient has overdosed in the intensive care unit, though withdrawal syndromes should be prevented, and communication with outpatient prescribers is vital. Understanding the diagnosis and appropriate management of these four psychiatric emergencies is important to provide safe and effective care in the intensive care unit.

  6. 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.

  7. Small systems meet superfund challenge with point-of-entry treatment units

    SciTech Connect

    Goodrich, J.A.; Stevens, T.; Walsh, C.

    1991-12-01

    Several small systems and individual homeowners have been faced with the task of treating their groundwater that has been contaminated with various organic contaminants. Contamination is such that the locations described in this presentation have been designated Federal Superfund sites undergoing emergency or remedial actions. These sites have utilized point-of-entry water treatment devices to treat their groundwater. The devices used include: single and dual granular activated carbon (GAC) columns; air stripping in series with GAC; and ozone/UV followed by GAC. Cost (capital and operating) contaminant removal performance, GAC breakthrough and disinfection byproduct formation will be discussed for several Superfund or state led cleanup actions.

  8. 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.

  9. Biological treatment of groundwater contaminated with mixtures of aromatic compounds. Final report, August-December 1990

    SciTech Connect

    Pettigrew, C.A.; Spain, J.; Vogel, C.M.

    1993-03-01

    This report presents the results of a 3-week preliminary field demonstration using an aboveground fixed-film bioreactor to biodegrade chlorinated aromatic compounds. The site at Kelly AFB, TX is an abandoned waste storage area where the soil and groundwater is contaminated with a mixture of chlorinated solvents. Contaminant removal by a reactor colonized with Pseudomonas sp. JS150 was compared to that of a reactor colonized with indigenous groundwater bacteria. Other process measurements included temperature, pH, dissolved oxygen, and fluctuations in microbial populations. Both biofilm populations degraded the organic compounds when the reactors were operated at a hydraulic residence time of 40 minutes. The concentrations of volatile organic compounds were reduced from the mg/l to the low ug/l range when sufficient dissolved oxygen was maintained. These results indicate that high removal efficiencies for complex mixtures of organic compounds can be achieved by immobilized bacterial populations. Bioremediation, Fixed-film bioreactor, Pseudomonas strain JS150, Chlorinated aromatic compounds.

  10. Sulfur-based autotrophic denitrification with eggshell for nitrate-contaminated synthetic groundwater treatment.

    PubMed

    Xu, Yaxian; Chen, Nan; Feng, Chuanping; Hao, Chunbo; Peng, Tong

    2016-12-01

    Eggshell is considered to be a waste and a significant quantity of eggshell waste is generated from food processing, baking and hatching industries. In this study, the effect of different sulfur/eggshell (w/w) ratios and temperatures was investigated to evaluate the feasibility of the sulfur-based autotrophic denitrification with eggshell (SADE) process for nitrate removal. The results showed eggshell can maintain a neutral condition in a range of pH 7.05-7.74 in the SADE process, and remove 97% of nitrate in synthetic groundwater. Compared with oyster shell and limestone, eggshell was found to be a desirable alkaline material for sulfur-based autotrophic denitrification (SAD) with no nitrite accumulation and insignificant sulfate production. Denitrification reaction was found to follow the first-order kinetic models (R(2) > .9) having nitrate removal rate constants of 0.85 and 0.93 d(-1) for raw eggshell and boiled eggshell, respectively. Sulfur/eggshell ratio of 2:3 provided the best efficiency on nitrate removal. Nitrate was removed completely by the SADE process at a low temperature of 15°C. Eggshell could be used for the SAD process due to its good effect for nitrate removal from groundwater.

  11. 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

  12. Outpatient hypertension treatment, treatment intensification, and control in Western Europe and the United States.

    PubMed

    Wang, Y Richard; Alexander, G Caleb; Stafford, Randall S

    2007-01-22

    Hypertension guidelines in the United States tend to have more aggressive treatment recommendations than those in European countries. To explore international differences in hypertension treatment, treatment intensification, and hypertension control in western Europe and the United States, we conducted cross-sectional analyses of the nationally representative CardioMonitor 2004 survey, which included 21 053 hypertensive patients visiting 291 cardiologists and 1284 primary care physicians in 5 western European countries and the United States. The main outcome measures were latest systolic and diastolic blood pressure (BP) levels, hypertension control (latest BP level, <140/90 mm Hg), and medication increase (dose escalation or an addition to or switch of drug therapy) for inadequately controlled hypertension. At least 92% of patients in each country received antihypertensive drug treatment. The initial pretreatment BP levels were lowest and the use of combination drug therapy (>or=2 antihypertensive drug classes) was highest in the United States. Multivariate analyses controlling for age, sex, current smoking, and physician specialty indicated that, compared with US patients, European patients had higher latest systolic BP levels (by 5.3-10.2 mm Hg across countries examined) and diastolic BP levels (by 1.9-5.3 mm Hg), a smaller likelihood of hypertension control (odds ratios, 0.27-0.50), and a smaller likelihood of medication increase for inadequately controlled hypertension (odds ratios, 0.29-0.65) (all P<.001). In addition, controlling for initial pretreatment BP level attenuated the differences in latest systolic and diastolic BP levels and the likelihood of hypertension control. Lower treatment thresholds and more intensive treatment contribute to better hypertension control in the United States compared with the western European countries studied.

  13. Detection of pharmaceuticals and other personal care products in groundwater beneath and adjacent to onsite wastewater treatment systems in a coastal plain shallow aquifer.

    PubMed

    Del Rosario, Katie L; Mitra, Siddhartha; Humphrey, Charles P; O'Driscoll, Michael A

    2014-07-15

    Onsite wastewater treatment systems (OWTS) are the predominant disposal method for human waste in areas without municipal sewage treatment alternatives. Relatively few studies have addressed the release of pharmaceuticals and personal care products (PPCPs) from OWTS to groundwater. PPCP fate and transport from OWTS are important, particularly where these systems are adjacent to sensitive aquatic ecosystems such as coastal areas or wetlands. The objectives of this study were to identify PPCPs in residential wastewater and groundwater beneath OWTS and to characterize the environmental conditions affecting the OWTS discharge of PPCPs to nearby streams. The study sites are in coastal plain aquifers, which may be considered vulnerable "end-members" for subsurface PPCP transport. The PPCPs most commonly detected in the OWTS, at concentrations ranging from 0.12 μg L(-1) to 12.04 μg L(-1) in the groundwater, included: caffeine, ibuprofen, DEET, and homosalate. Their presence was related to particulate and dissolved organic carbon abundance.

  14. 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

  15. Ground-Water Quality Data in the Upper Santa Ana Watershed Study Unit, November 2006-March 2007: Results from the California GAMA Program

    USGS Publications Warehouse

    Kent, Robert; Belitz, Kenneth

    2009-01-01

    Ground-water quality in the approximately 1,000-square-mile Upper Santa Ana Watershed study unit (USAW) was investigated from November 2006 through 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 Upper Santa Ana Watershed study was designed to provide a spatially unbiased assessment of raw ground-water quality within USAW, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 99 wells in Riverside and San Bernardino Counties. Ninety of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells). Nine wells were selected to provide additional understanding of specific water-quality issues identified within the basin (understanding wells). The ground-water samples were analyzed for a large number of organic constituents (volatile organic compounds [VOCs], pesticides and pesticide degradates, pharmaceutical compounds, and potential wastewater-indicator compounds), constituents of special interest (perchlorate, N-nitrosodimethylamine [NDMA], 1,4-dioxane, 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 and oxygen in water) and dissolved noble gases also were measured to help identify sources and ages of the sampled ground water. Dissolved gases, and isotopes of nitrogen gas and of dissolved nitrate also were measured in order to investigate the sources and occurrence of

  16. Groundwater data network interoperability

    USGS Publications Warehouse

    Brodaric, Boyan; Booth, Nathaniel; Boisvert, Eric; Lucido, Jessica M.

    2016-01-01

    Water data networks are increasingly being integrated to answer complex scientific questions that often span large geographical areas and cross political borders. Data heterogeneity is a major obstacle that impedes interoperability within and between such networks. It is resolved here for groundwater data at five levels of interoperability, within a Spatial Data Infrastructure architecture. The result is a pair of distinct national groundwater data networks for the United States and Canada, and a combined data network in which they are interoperable. This combined data network enables, for the first time, transparent public access to harmonized groundwater data from both sides of the shared international border.

  17. 10 CFR 35.2652 - Records of surveys of therapeutic treatment units.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Records of surveys of therapeutic treatment units. (a) A licensee shall maintain a record of radiation... serial number of the treatment unit, source, and instrument used to measure radiation levels; (3) Each... 10 Energy 1 2010-01-01 2010-01-01 false Records of surveys of therapeutic treatment units. 35.2652...

  18. 10 CFR 35.2652 - Records of surveys of therapeutic treatment units.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Records of surveys of therapeutic treatment units. (a) A licensee shall maintain a record of radiation... serial number of the treatment unit, source, and instrument used to measure radiation levels; (3) Each... 10 Energy 1 2012-01-01 2012-01-01 false Records of surveys of therapeutic treatment units. 35.2652...

  19. 10 CFR 35.2652 - Records of surveys of therapeutic treatment units.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Records of surveys of therapeutic treatment units. (a) A licensee shall maintain a record of radiation... serial number of the treatment unit, source, and instrument used to measure radiation levels; (3) Each... 10 Energy 1 2014-01-01 2014-01-01 false Records of surveys of therapeutic treatment units. 35.2652...

  20. 10 CFR 35.2652 - Records of surveys of therapeutic treatment units.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Records of surveys of therapeutic treatment units. (a) A licensee shall maintain a record of radiation... serial number of the treatment unit, source, and instrument used to measure radiation levels; (3) Each... 10 Energy 1 2011-01-01 2011-01-01 false Records of surveys of therapeutic treatment units. 35.2652...

  1. 10 CFR 35.2652 - Records of surveys of therapeutic treatment units.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Records of surveys of therapeutic treatment units. (a) A licensee shall maintain a record of radiation... serial number of the treatment unit, source, and instrument used to measure radiation levels; (3) Each... 10 Energy 1 2013-01-01 2013-01-01 false Records of surveys of therapeutic treatment units. 35.2652...

  2. 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.

  3. 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.

  4. 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

    2013-05-07

    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.

  5. Dominance of sphingomonads in a copper-exposed biofilm community for groundwater treatment.

    PubMed

    Vílchez, R; Pozo, C; Gómez, M A; Rodelas, B; González-López, J

    2007-02-01

    The structure, biological activity and microbial biodiversity of a biofilm used for the removal of copper from groundwater were studied and compared with those of a biofilm grown under copper-free conditions. A laboratory-scale submerged fixed biofilter was fed with groundwater (2.3 l h(-1)) artificially polluted with Cu(II) (15 mg l(-1)) and amended with sucrose (150 mg l(-1)) as carbon source. Between 73 and 90 % of the Cu(II) was removed from water during long-term operation (over 200 days). The biofilm was a complex ecosystem, consisting of eukaryotic and prokaryotic micro-organisms. Scanning electron microscopy revealed marked structural changes in the biofilm induced by Cu(II), compared to the biofilm grown in absence of the heavy metal. Analysis of cell-bound extracellular polymeric substances (EPS) demonstrated a significant modification of the composition of cell envelopes in response to Cu(II). Transmission electron microscopy and energy-dispersive X-ray microanalysis (EDX) showed that copper bioaccumulated in the EPS matrix by becoming bound to phosphates and/or silicates, whereas copper accumulated only intracytoplasmically in cells of eukaryotic microbes. Cu(II) also decreased sucrose consumption, ATP content and alkaline phosphatase activity of the biofilm. A detailed study of the bacterial community composition was conducted by 16S rRNA-based temperature gradient gel electrophoresis (TGGE) profiling, which showed spatial and temporal stability of the species diversity of copper-exposed biofilms during biofilter operation. PCR reamplification and sequencing of 14 TGGE bands showed the prevalence of alphaproteobacteria, with most sequences (78 %) affiliated to the Sphingomonadaceae. The major cultivable colony type in plate counts of the copper-exposed biofilm was also identified as that of Sphingomonas sp. These data confirm a major role of these organisms in the composition of the Cu(II)-removing community.

  6. Groundwater quality in the Sierra Nevada, California

    USGS Publications Warehouse

    Fram, Miranda S.; 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 (PBP) of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. The Sierra Nevada Regional study unit constitutes one of the study units being evaluated.

  7. Environmental behavior of explosives in groundwater from the Milan Army Ammunition Plant in aquatic and wetland plant treatments. Removal, mass balances and fate in groundwater of TNT and RDX.

    PubMed

    Best, E P; Sprecher, S L; Larson, S L; Fredrickson, H L; Bader, D F

    1999-06-01

    Phytoremediation of 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in groundwater using constructed wetlands is a potentially economical remediation alternative. To evaluate Explosives removal and fate was evaluated using hydroponic batch incubations of plant and substrate treatments with explosives-contaminated groundwater amended with [U-14C]-TNT or [U-14C]-RDX. Plants and substrates were collected from a small-scale wetland constructed for explosives removal, and groundwater originated from a local aquifer at the Milan Army Ammunition Plant. The study surveyed three aquatic, four wetland plant species and two substrates in independent incubations of 7 days with TNT and 13 days with RDX. Parent compounds and transformation products were followed using 14C and chemical (HPLC) analyses. Mass balance of water, plants, substrates and air was determined. It was demonstrated that TNT disappeared completely from groundwater incubated with plants, although growth of most plants except parrot-feather was low in groundwater amended to contain 1.6 to 3.4 mg TNT L-1. Highest specific removal rates were found in submersed plants in water star-grass and in all emergent plants except wool-grass. TNT declined less with substrates, and least in controls without plants. Radiolabel was present in all plants after incubation. Mineralization to 14CO2 was very low, and evolution into 14C-volatile organics negligible. RDX disappeared less rapidly than TNT from groundwater. Growth of submersed plants was normal, but that of emergent plants reduced in groundwater amended to contain 1.5 mg RDX L-1. Highest specific RDX removal rates were found in submersed plants in elodea, and in emergent plants in reed canary grass. RDX failed to disappear with substrates. Mineralization to 14CO2 was low, but relatively higher than in the TNT experiment. Evolution into 14C-volatile organics was negligible. Important considerations for using certain aquatic and wetland

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

    USGS Publications Warehouse

    Belcher, Wayne R.; Sweetkind, Donald S.; Elliott, Peggy E.

    2002-01-01

    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 hydrologically 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 hydraulic 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.

  9. 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.

  10. 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

  11. 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.

  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. 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.

  14. 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.

  15. 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.

  16. 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).

  17. Bacterial Succession in a Petroleum Land Treatment Unit

    PubMed Central

    Kaplan, Christopher W.; Kitts, Christopher L.

    2004-01-01

    Bacterial community dynamics were investigated in a land treatment unit (LTU) established at a site contaminated with highly weathered petroleum hydrocarbons in the C10 to C32 range. The treatment plot, 3,000 cubic yards of soil, was supplemented with nutrients and monitored weekly for total petroleum hydrocarbons (TPH), soil water content, nutrient levels, and aerobic heterotrophic bacterial counts. Weekly soil samples were analyzed with 16S rRNA gene terminal restriction fragment (TRF) analysis to monitor bacterial community structure and dynamics during bioremediation. TPH degradation was rapid during the first 3 weeks and slowed for the remainder of the 24-week project. A sharp increase in plate counts was reported during the first 3 weeks, indicating an increase in biomass associated with petroleum degradation. Principal components analysis of TRF patterns revealed a series of sample clusters describing bacterial succession during the study. The largest shifts in bacterial community structure began as the TPH degradation rate slowed and the bacterial cell counts decreased. For the purpose of analyzing bacterial dynamics, phylotypes were generated by associating TRFs from three enzyme digests with 16S rRNA gene clones. Two phylotypes associated with Flavobacterium and Pseudomonas were dominant in TRF patterns from samples during rapid TPH degradation. After the TPH degradation rate slowed, four other phylotypes gained dominance in the community while Flavobacterium and Pseudomonas phylotypes decreased in abundance. These data suggest that specific phylotypes of bacteria were associated with the different phases of petroleum degradation in the LTU. PMID:15006804

  18. Prevention and treatment of aspiration pneumonia in intensive care units.

    PubMed

    d'Escrivan, Thibaud; Guery, Benoit

    2005-01-01

    Aspiration is a leading cause of nosocomial infection in the intensive care unit. Techniques to avoid or reduce aspiration are important in preventing pneumonia and pneumonitis. The most important preventive measures include the semi-recumbent position, the surveillance of enteral feeding, the use of promotility agents, and avoiding excessive sedation. The analysis of the pathogens involved in these syndromes usually shows a minor role for the anerobes. With regard to treatment, aspiration pneumonitis does not require any antimicrobials; on the contrary, aspiration pneumonia has to be treated. Empiric antimicrobials treatment should be started on clinical suspicion. The choice of the drug has to be guided by local pathogen epidemiology and clinical features; in fact, community type pneumonia requires a first-line antimicrobial such as amoxicillin/clavulanic acid. On the contrary, a nosocomial type of infection needs to be treated as a ventilator-associated pneumonia in agreement with published guidelines. Nevertheless, quantitative culture should be obtained in order to de-escalate antimicrobials. In conclusion, aspiration pneumonia is a frequently encountered disease that can be prevented by relatively simple measures.

  19. Bacterial succession in a petroleum land treatment unit.

    PubMed

    Kaplan, Christopher W; Kitts, Christopher L

    2004-03-01

    Bacterial community dynamics were investigated in a land treatment unit (LTU) established at a site contaminated with highly weathered petroleum hydrocarbons in the C(10) to C(32) range. The treatment plot, 3,000 cubic yards of soil, was supplemented with nutrients and monitored weekly for total petroleum hydrocarbons (TPH), soil water content, nutrient levels, and aerobic heterotrophic bacterial counts. Weekly soil samples were analyzed with 16S rRNA gene terminal restriction fragment (TRF) analysis to monitor bacterial community structure and dynamics during bioremediation. TPH degradation was rapid during the first 3 weeks and slowed for the remainder of the 24-week project. A sharp increase in plate counts was reported during the first 3 weeks, indicating an increase in biomass associated with petroleum degradation. Principal components analysis of TRF patterns revealed a series of sample clusters describing bacterial succession during the study. The largest shifts in bacterial community structure began as the TPH degradation rate slowed and the bacterial cell counts decreased. For the purpose of analyzing bacterial dynamics, phylotypes were generated by associating TRFs from three enzyme digests with 16S rRNA gene clones. Two phylotypes associated with Flavobacterium and Pseudomonas were dominant in TRF patterns from samples during rapid TPH degradation. After the TPH degradation rate slowed, four other phylotypes gained dominance in the community while Flavobacterium and Pseudomonas phylotypes decreased in abundance. These data suggest that specific phylotypes of bacteria were associated with the different phases of petroleum degradation in the LTU.

  20. 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.

  1. 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.

  2. In Situ Remediation of a TCE-Contaminated Aquifer Using a Short Rotation Woody Crop Groundwater Treatment System

    DTIC Science & Technology

    2006-05-01

    physiologically-based model (having the groundwater flow code MODFLOW ) was used to predict out-year transpiration rates and the magnitude and...to the difference in tree number). A groundwater flow model ( MODFLOW ) of the study area indicated the volume of water transpired from the aquifer...closes • MODFLOW (McDonald and Harbaugh, 1988)—A groundwater flow model used to predict observed effects of tree transpiration on the aquifer

  3. Fifteen-year assessment of a permeable reactive barrier for treatment of chromate and trichloroethylene in groundwater.

    PubMed

    Wilkin, Richard T; Acree, Steven D; Ross, Randall R; Puls, Robert W; Lee, Tony R; Woods, Leilani L

    2014-01-15

    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 source zone, reactive and hydraulic longevity of the PRB has outlived the mobile chromate plume. Chromium concentrations exceeding 3 μg/L have not been detected in regions located hydraulically down-gradient of the PRB. Trichloroethylene treatment has also been effective, although non-constant influent concentrations of trichloroethylene have at times resulted in incomplete dechlorination. Daughter products: cis-1,2-dichloroethylene, vinyl chloride, ethene, and ethane have been observed within and down-gradient of the PRB at levels <10% of the influent trichloroethylene. Analysis of potentiometric surfaces up-gradient and across the PRB suggests that the PRB may currently represent a zone of reduced hydraulic conductivity; however, measurements of the in-situ hydraulic conductivity provide values in excess of 200 m/d in some intervals and indicate no discernible loss of bulk hydraulic conductivity within the PRB. The results presented here are particularly significant because they provide the longest available record of performance of a PRB. The longevity of the Elizabeth City PRB is principally the result of favorable groundwater geochemistry and hydrologic properties of the site. © 2013.

  4. 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.

  5. Performance of electron beam irradiation for treatment of groundwater contaminated with acetone.

    PubMed

    Yoon, Y J; Jung, Y J; Han, B S; Kang, J W

    2009-01-01

    The purposes of this study were to evaluate the efficiency of acetone removal by electron beam irradiation in groundwater and the effect of various conditions. According to the results, the removal kinetics of acetone were pseudo first-order, and the removal efficiencies were expressed to the (%) removal and G-values. By adding sulfite, it was confirmed that acetone was mainly degraded by the reaction with the hydrated electrons. The presence of nitrate caused the removal of acetone to decrease. But there was no significant effect of alkalinity on the removal of acetone. The effect of the initial pH values (pH 5 to 9) on the acetone removal efficiency was negligible, but the pH value decreases due to the formation of acidic compounds after irradiation. Consequently, the radiation-induced removal reactions of acetone followed the pseudo-first-order kinetic model; in addition to the initial concentration of acetone, nitrate and the absorbed dose were important factors in removing acetone from an aqueous solution using electron beam irradiation. The effects of general pH and alkalinity on the degrading acetone were negligible.

  6. Effects of nitrate on the treatment of lead contaminated groundwater by nanoscale zerovalent iron.

    PubMed

    Su, Yiming; Adeleye, Adeyemi S; Zhou, Xuefei; Dai, Chaomeng; Zhang, Weixian; Keller, Arturo A; Zhang, Yalei

    2014-09-15

    Nanoscale zerovalent iron (nZVI) is efficient for removing Pb(2+) and nitrate from water. However, the influence of nitrate, a common groundwater anion, on Pb(2+) removal by nZVI is not well understood. In this study, we showed that under excess Fe(0) conditions (molar ratio of Fe(0)/nitrate>4), Pb(2+) ions were immobilized more quickly (<5 min) than in nitrate-free systems (∼ 15 min) due to increasing pH. With nitrate in excess (molar ratio of Fe(0)/nitrate<4), nitrate stimulated the formation of crystal PbxFe3-xO4 (ferrite), which provided additional Pb(2+) removal. However, ∼ 7% of immobilized Pb(2+) ions were released into aqueous phase within 2h due to ferrite deformation. Oxidation-reduction potential (ORP) values below -600 mV correlated with excess Fe(0) conditions (complete Pb(2+) immobilization), while ORP values ≥-475 mV characterized excess nitrate conditions (ferrite process and Pb(2+) release occurrence). This study indicates that ORP monitoring is important for proper management of nZVI-based remediation in the subsurface to avoid lead remobilization in the presence of nitrate.

  7. Alkaline Hydrolysis is an Effective Treatment Technology for RDX-Contaminated Groundwater

    SciTech Connect

    Hqang, Snagchul; Felt, Deborah R.; Bouwer, Edward J.; Brooks, Michael C.; Larson, Steven L.; Davis, Jeffrey L.

    2003-03-26

    Kinetics and treatability of alkaline hydrolysis were investigated in batch reactor and continuous flow-stirred tank reactor (CFSTR) for remediating groundwater contaminated with hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). The batch system (pH 11 to 13, RDX 1 to 10 mg/L) achieved pseudo first-order RDX transformation rates in the range of 0.2 to 47.5 min-1, corresponding to 57.8 to 0.2 hrs of half-life period, respectively. In the CFSTR system (pH 11 to 11.9, HRT 0.54 to 2 days), the best alkaline RDX transformation was achieved a 99% RDX removal with the longest HRT and the highest reaction pH. Formate ({approx}2 M/M RDXremoved) and nitrite ({approx}0.2 M/M RDXremoved) were produced as the major hydrolysates, indicative of a simultaneous transformation mechanism by RDX ring cleavage and ring nitrogen elimination. The net OH- demand was found to be 1.5, 390 and 130 M OH-/M RDXremoved at the pH of 11.9, 11.5 and 11.0, respectively, in the CFSTR system.

  8. 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.

  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. The bioelectric well: a novel approach for in situ treatment of hydrocarbon-contaminated groundwater.

    PubMed

    Palma, Enza; Daghio, Matteo; Franzetti, Andrea; Petrangeli Papini, Marco; Aulenta, Federico

    2017-07-11

    Groundwater contamination by petroleum hydrocarbons (PHs) is a widespread problem which poses serious environmental and health concerns. Recently, microbial electrochemical technologies (MET) have attracted considerable attention for remediation applications, having the potential to overcome some of the limiting factors of conventional in situ bioremediation systems. So far, field-scale application of MET has been largely hindered by the limited availability of scalable system configurations. Here, we describe the 'bioelectric well' a bioelectrochemical reactor configuration, which can be installed directly within groundwater wells and can be applied for in situ treatment of organic contaminants, such as PHs. A laboratory-scale prototype of the bioelectric well has been set up and operated in continuous-flow regime with phenol as the model contaminant. The best performance was obtained when the system was inoculated with refinery sludge and the anode potentiostatically controlled at +0.2 V versus SHE. Under this condition, the influent phenol (25 mg l(-1) ) was nearly completely (99.5 ± 0.4%) removed, with an average degradation rate of 59 ± 3 mg l(-1) d and a coulombic efficiency of 104 ± 4%. Microbial community analysis revealed a remarkable enrichment of Geobacter species on the surface of the graphite anode, clearly pointing to a direct involvement of this electro-active bacterium in the current-generating and phenol-oxidizing process. © 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  11. 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.

  12. Laboratory and pilot-scale evaluations of physical/chemical treatment technologies for MGP site groundwaters. Topical report, January 1989-May 1990

    SciTech Connect

    Weightman, R.L.; Smith, J.R.

    1990-05-01

    Treatability studies were performed to evaluate the treatment of Manufactured Gas Plant (MGP) site groundwaters using the following treatment