This chapter compiles available chemical and radiation toxicity information for plants and animals from the scientific literature on naturally occurring uranium and associated radionuclides. Specifically, chemical and radiation hazards associated with radionuclides in the uranium decay series including uranium, thallium, thorium, bismuth, radium, radon, protactinium, polonium, actinium, and francium were the focus of the literature compilation. In addition, exposure pathways and a food web specific to the segregation areas were developed. Major biological exposure pathways considered were ingestion, inhalation, absorption, and bioaccumulation, and biota categories included microbes, invertebrates, plants, fishes, amphibians, reptiles, birds, and mammals. These data were developed for incorporation into a risk assessment to be conducted as part of an environmental impact statement for the Bureau of Land Management, which would identify representative plants and animals and their relative sensitivities to exposure of uranium and associated radionuclides. This chapter provides pertinent information to aid in the development of such an ecological risk assessment but does not estimate or derive guidance thresholds for radionuclides associated with uranium.
Previous studies have not attempted to quantify the risks to biota caused directly by the chemical or radiation releases at uranium mining sites, although some information is available for uranium mill tailings and uranium mine closure activities. Research into the biological impacts of uranium exposure is strongly biased towards human health and exposure related to enriched or depleted uranium associated with the nuclear energy industry rather than naturally occurring uranium associated with uranium mining. Nevertheless, studies have reported that uranium and other radionuclides can affect the survival, growth, and reproduction of plants and animals.
Exposure to chemical and radiation hazards is influenced by a plant’s or an animal’s life history and surrounding environment. Various species of plants, invertebrates, fishes, amphibians, reptiles, birds, and mammals found in the segregation areas that are considered species of concern by State and Federal agencies were included in the development of the site-specific food web. The utilization of subterranean habitats (burrows in uranium-rich areas, burrows in waste rock piles or reclaimed mining areas, mine tunnels) in the seasonally variable but consistently hot, arid environment is of particular concern in the segregation areas. Certain species of reptiles, amphibians, birds, and mammals in the segregation areas spend significant amounts of time in burrows where they can inhale or ingest uranium and other radionuclides through digging, eating, preening, and hibernating. Herbivores may also be exposed though the ingestion of radionuclides that have been aerially deposited on vegetation. Measured tissues concentrations of uranium and other radionuclides are not available for any species of concern in the segregation areas. The sensitivity of these animals to uranium exposure is unknown based on the existing scientific literature, and species-specific uranium presumptive effects levels were only available for two endangered fish species known to inhabit the segregation areas.
Overall, the chemical toxicity data available for biological receptors of concern were limited, although chemical and radiation toxicity guidance values are available from several sources. However, caution should be used when directly applying these values to northern Arizona given the unique habitat and life history strategies of biological receptors in the segregation areas and the fact that some guidance values are based on models rather than empirical (laboratory or field) data. No chemical toxicity information based on empirical data is available for reptiles, birds, or wild mammals; therefore, the risks associated with uranium and other radionuclides are unknown for these biota.
","largerWorkType":{"id":18,"text":"Report"},"largerWorkTitle":"Hydrological, geological, and biological site characterization of breccia pipe uranium deposits in Northern Arizona (Scientific Investigations Report 2010-5025)","largerWorkSubtype":{"id":5,"text":"USGS Numbered Series"},"language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20105025D","usgsCitation":"Hinck, J.E., Linder, G.L., Finger, S.E., Little, E.E., Tillitt, D.E., and Kuhne, W., 2010, Biological pathways of exposure and ecotoxicity values for uranium and associated radionuclides: Chapter D in Hydrological, geological, and biological site characterization of breccia pipe uranium deposits in Northern Arizona: U.S. Geological Survey Scientific Investigations Report 2010-5025, 69, https://doi.org/10.3133/sir20105025D.","productDescription":"69","startPage":"283","endPage":"351","costCenters":[{"id":192,"text":"Columbia Environmental Research Center","active":true,"usgs":true}],"links":[{"id":344076,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"},{"id":372514,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/sir/2010/5025/pdf/sir2010-5025_biology.pdf","linkFileType":{"id":1,"text":"pdf"}}],"country":"United States","state":"Arizona","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -114,\n 37.1\n ],\n [\n -111.5,\n 37.1\n ],\n [\n -111.5,\n 35.5\n ],\n [\n -114,\n 35.5\n ],\n [\n -114,\n 37.1\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"59706fdfe4b0d1f9f065ab0c","contributors":{"authors":[{"text":"Hinck, Jo Ellen 0000-0002-4912-5766 jhinck@usgs.gov","orcid":"https://orcid.org/0000-0002-4912-5766","contributorId":2743,"corporation":false,"usgs":true,"family":"Hinck","given":"Jo","email":"jhinck@usgs.gov","middleInitial":"Ellen","affiliations":[{"id":192,"text":"Columbia Environmental Research Center","active":true,"usgs":true}],"preferred":true,"id":705694,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Linder, Greg L. linder2@usgs.gov","contributorId":1766,"corporation":false,"usgs":true,"family":"Linder","given":"Greg","email":"linder2@usgs.gov","middleInitial":"L.","affiliations":[{"id":192,"text":"Columbia Environmental Research Center","active":true,"usgs":true}],"preferred":false,"id":705695,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Finger, Susan E. sfinger@usgs.gov","contributorId":1317,"corporation":false,"usgs":true,"family":"Finger","given":"Susan","email":"sfinger@usgs.gov","middleInitial":"E.","affiliations":[],"preferred":true,"id":705696,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Little, Edward E. 0000-0003-0034-3639 elittle@usgs.gov","orcid":"https://orcid.org/0000-0003-0034-3639","contributorId":1746,"corporation":false,"usgs":true,"family":"Little","given":"Edward","email":"elittle@usgs.gov","middleInitial":"E.","affiliations":[{"id":192,"text":"Columbia Environmental Research Center","active":true,"usgs":true}],"preferred":true,"id":705697,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Tillitt, Donald E. 0000-0002-8278-3955 dtillitt@usgs.gov","orcid":"https://orcid.org/0000-0002-8278-3955","contributorId":1875,"corporation":false,"usgs":true,"family":"Tillitt","given":"Donald","email":"dtillitt@usgs.gov","middleInitial":"E.","affiliations":[{"id":192,"text":"Columbia Environmental Research Center","active":true,"usgs":true}],"preferred":true,"id":705698,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Kuhne, Wendy","contributorId":194911,"corporation":false,"usgs":false,"family":"Kuhne","given":"Wendy","affiliations":[],"preferred":false,"id":705699,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":98407,"text":"sir20105024 - 2010 - Quality of Source Water from Public-Supply Wells in the United States, 1993-2007","interactions":[],"lastModifiedDate":"2012-02-02T00:15:05","indexId":"sir20105024","displayToPublicDate":"2010-05-22T00:00:00","publicationYear":"2010","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":334,"text":"Scientific Investigations Report","code":"SIR","onlineIssn":"2328-0328","printIssn":"2328-031X","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2010-5024","title":"Quality of Source Water from Public-Supply Wells in the United States, 1993-2007","docAbstract":"More than one-third of the Nation's population receives their drinking water from public water systems that use groundwater as their source. The U.S. Geological Survey (USGS) sampled untreated source water from 932 public-supply wells, hereafter referred to as public wells, as part of multiple groundwater assessments conducted across the Nation during 1993-2007. The objectives of this study were to evaluate (1) contaminant occurrence in source water from public wells and the potential significance of contaminant concentrations to human health, (2) national and regional distributions of groundwater quality, and (3) the occurrence and characteristics of contaminant mixtures. Treated finished water was not sampled. \r\n\r\nThe 932 public wells are widely distributed nationally and include wells in selected parts of 41 states and withdraw water from parts of 30 regionally extensive aquifers used for public water supply. These wells are distributed among 629 unique public water systems-less than 1 percent of all groundwater-supplied public water systems in the United States-but the wells were randomly selected within the sampled hydrogeologic settings to represent typical aquifer conditions. Samples from the 629 systems represent source water used by one-quarter of the U.S. population served by groundwater-supplied public water systems, or about 9 percent of the entire U.S. population in 2008. \r\n\r\nOne groundwater sample was collected prior to treatment or blending from each of the 932 public wells and analyzed for as many as six water-quality properties and 215 contaminants. Consistent with the terminology used in the Safe Drinking Water Act (SDWA), all constituents analyzed in water samples in this study are referred to as 'contaminants'. More contaminant groups were assessed in this study than in any previous national study of public wells and included major ions, nutrients, radionuclides, trace elements, pesticide compounds, volatile organic compounds (VOCs), and fecal-indicator microorganisms. Contaminant mixtures were assessed in subsets of samples in which most contaminants were analyzed. \r\n\r\nContaminant concentrations were compared to human-health benchmarks-regulatory U.S. Environmental Protection Agency (USEPA) Maximum Contaminant Levels (MCLs) for contaminants regulated in drinking water under the SDWA or non-regulatory USGS Health-Based Screening Levels (HBSLs) for unregulated contaminants, when available. Nearly three-quarters of the contaminants assessed in this study are unregulated in drinking water, and the USEPA uses USGS data on the occurrence of unregulated contaminants in water resources to fulfill part of the SDWA requirements for determining whether specific contaminants should be regulated in drinking water in the future.\r\n\r\nMore than one in five (22 percent) source-water samples from public wells contained one or more naturally occurring or man-made contaminants at concentrations greater than human-health benchmarks, and 80 percent of samples contained one or more contaminants at concentrations greater than one-tenth of benchmarks. Most individual contaminant detections, however, were less than one-tenth of human-health benchmarks. Public wells yielding water with contaminant concentrations greater than benchmarks, as well as those with concentrations greater than one-tenth of benchmarks, were distributed throughout the United States and included wells that withdraw water from all principal aquifer rock types included in this study. \r\n\r\nTen contaminants individually were detected at concentrations greater than human-health benchmarks in at least 1 percent of source-water samples and collectively accounted for most concentrations greater than benchmarks. Seven of these 10 contaminants occur naturally, including three radionuclides (radon, radium, and gross alpha-particle radioactivity) and four trace elements (arsenic, manganese, strontium, and boron); three of these 10 contaminants (dieldrin, nitrate, and perchl","language":"ENGLISH","publisher":"U.S. Geological Survey","doi":"10.3133/sir20105024","collaboration":"National Water-Quality Assessment Program","usgsCitation":"Toccalino, P., Norman, J.E., and Hitt, K.J., 2010, Quality of Source Water from Public-Supply Wells in the United States, 1993-2007: U.S. Geological Survey Scientific Investigations Report 2010-5024, Report: xiv, 126 p.; Appendixes, https://doi.org/10.3133/sir20105024.","productDescription":"Report: xiv, 126 p.; Appendixes","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":451,"text":"National Water Quality Assessment Program","active":true,"usgs":true}],"links":[{"id":125407,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/sir_2010_5024.jpg"},{"id":13658,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/sir/2010/5024/","linkFileType":{"id":5,"text":"html"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4afce4b07f02db696895","contributors":{"authors":[{"text":"Toccalino, Patricia L. 0000-0003-1066-1702","orcid":"https://orcid.org/0000-0003-1066-1702","contributorId":41089,"corporation":false,"usgs":true,"family":"Toccalino","given":"Patricia L.","affiliations":[{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"preferred":true,"id":305225,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Norman, Julia E. 0000-0002-2820-6225 jnorman@usgs.gov","orcid":"https://orcid.org/0000-0002-2820-6225","contributorId":3832,"corporation":false,"usgs":true,"family":"Norman","given":"Julia","email":"jnorman@usgs.gov","middleInitial":"E.","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true},{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true},{"id":518,"text":"Oregon Water Science Center","active":true,"usgs":true}],"preferred":true,"id":305224,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hitt, Kerie J.","contributorId":54565,"corporation":false,"usgs":true,"family":"Hitt","given":"Kerie","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":305226,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":98191,"text":"ds474 - 2010 - Groundwater-quality data in the Colorado River study unit, 2007: Results from the California GAMA Program","interactions":[],"lastModifiedDate":"2022-07-20T12:11:49.113236","indexId":"ds474","displayToPublicDate":"2010-02-13T00:00:00","publicationYear":"2010","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":310,"text":"Data Series","code":"DS","onlineIssn":"2327-638X","printIssn":"2327-0271","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"474","title":"Groundwater-quality data in the Colorado River study unit, 2007: Results from the California GAMA Program","docAbstract":"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 approximately 30 percent of the wells, and the results were used to evaluate the quality of the data obtained from the groundwater samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that contamination was not a significant source of bias in the data. Differences between replicate samples were within acceptable ranges and matrix-spike recoveries were within acceptable ranges for most compounds.
This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, raw groundwater typically is treated, disinfected, or blended with other waters to maintain acceptable water quality. Regulatory thresholds apply to water that is served to the consumer, not to raw groundwater. However, to provide some context for the results, concentrations of constituents measured in the raw groundwater were compared to regulatory and nonregulatory health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and the California Department of Public Health (CDPH) and to thresholds established for aesthetic concerns by CDPH. Comparisons between data collected for this study and drinking-water thresholds are for illustrative purposes only and do not indicate compliance or noncompliance with those thresholds.
The concentrations of most constituents detected in groundwater samples were below drinking-water thresholds. Volatile organic compounds (VOC) were detected in approximately 35 percent of grid well samples; all concentrations were below health-based thresholds. Pesticides and pesticide degradates were detected in about 20 percent of all samples; detections were below health-based thresholds. No concentrations of constituents of special interest or nutrients were detected above health-based thresholds. Most of the major and minor ion constituents sampled do not have health-based thresholds; the exception is chloride. Concentrations of chloride, sulfate, and total dissolved solids detected in some of the well samples were above the nonenforceable thresholds for aesthetic concerns. Concentrations of fluoride were detected in 5 samples (from 4 grid wells and 1 understanding well) above the maximum contaminant level for California (MCL-CA). Concentrations of most of the trace elements in samples from the COLOR study were below health-based thresholds; exceptions included arsenic above the MCL-US, boron above the notification level for California (NL-CA), iron and manganese above the secondary maximum contaminant level for California (SMCL-CA), and molybdenum and strontium above the lifetime health advisory level (HAL-US) threshold. Most detections of radioactive constituents were below health-based thresholds; exceptions were alpha, uranium, and radon radioactivity. Alpha radioactivity with 72 hour count detections occurred in four grid wells and one understanding well, and 30-day count detections in two grid wells above the MCL-US. Uranium was detected twice in grid wells above the MCL-US threshold. Also, radon-222 was detected at concentrations above the proposed MCL-US in 19 samples (14 grid and 5 understanding wells). No radon-222 was detected above the proposed MCL-US upper threshold.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ds474","collaboration":"Prepared in cooperation with the California State Water Resources Control Board","usgsCitation":"Goldrath, D., Wright, M.T., and Belitz, K., 2010, Groundwater-quality data in the Colorado River study unit, 2007: Results from the California GAMA Program: U.S. Geological Survey Data Series 474, x, 66 p., https://doi.org/10.3133/ds474.","productDescription":"x, 66 p.","onlineOnly":"N","additionalOnlineFiles":"N","temporalStart":"2007-10-01","temporalEnd":"2007-12-31","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":199350,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"},{"id":13435,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/ds/474/","linkFileType":{"id":5,"text":"html"}},{"id":404080,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_91388.htm","linkFileType":{"id":5,"text":"html"}}],"projection":"Albers Equal Area Conic Projection","country":"United States","state":"California","otherGeospatial":"Colorado River study unit","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -114.9167,\n 32.7203\n ],\n [\n -114.4167,\n 32.7203\n ],\n [\n -114.4167,\n 35.0667\n ],\n [\n -114.9167,\n 35.0667\n ],\n [\n -114.9167,\n 32.7203\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a94e4b07f02db65897b","contributors":{"authors":[{"text":"Goldrath, Dara A.","contributorId":59896,"corporation":false,"usgs":true,"family":"Goldrath","given":"Dara A.","affiliations":[],"preferred":false,"id":304624,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wright, Michael T. 0000-0003-0653-6466 mtwright@usgs.gov","orcid":"https://orcid.org/0000-0003-0653-6466","contributorId":1508,"corporation":false,"usgs":true,"family":"Wright","given":"Michael","email":"mtwright@usgs.gov","middleInitial":"T.","affiliations":[],"preferred":false,"id":304623,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Belitz, Kenneth 0000-0003-4481-2345 kbelitz@usgs.gov","orcid":"https://orcid.org/0000-0003-4481-2345","contributorId":442,"corporation":false,"usgs":true,"family":"Belitz","given":"Kenneth","email":"kbelitz@usgs.gov","affiliations":[{"id":27111,"text":"National Water Quality Program","active":true,"usgs":true},{"id":466,"text":"New England Water Science Center","active":true,"usgs":true},{"id":451,"text":"National Water Quality Assessment Program","active":true,"usgs":true},{"id":503,"text":"Office of Water Quality","active":true,"usgs":true},{"id":376,"text":"Massachusetts Water Science Center","active":true,"usgs":true}],"preferred":true,"id":304622,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":98181,"text":"ofr20091273 - 2010 - Investigation of submarine groundwater discharge along the tidal reach of the Caloosahatchee River, southwest Florida","interactions":[],"lastModifiedDate":"2023-12-07T14:32:15.739899","indexId":"ofr20091273","displayToPublicDate":"2010-02-10T00:00:00","publicationYear":"2010","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":330,"text":"Open-File Report","code":"OFR","onlineIssn":"2331-1258","printIssn":"0196-1497","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2009-1273","title":"Investigation of submarine groundwater discharge along the tidal reach of the Caloosahatchee River, southwest Florida","docAbstract":"The tidal reach of the Caloosahatchee River is an estuarine habitat that supports a diverse assemblage of biota including aquatic vegetation, shellfish, and finfish. The system has been highly modified by anthropogenic activity over the last 150 years (South Florida Water Management District (SFWMD), 2009). For example, the river was channelized and connected to Lake Okeechobee in 1881 (via canal C-43). Subsequently, three control structures (spillway and locks) were installed for flood protection (S-77 and S-78 in the 1930s) and for saltwater-intrusion prevention (S-79, W.P. Franklin Lock and Dam in 1966). The emplacement of these structures and their impact to natural water flow have been blamed for water-quality problems downstream within the estuary (Flaig and Capece, 1998; SFWMD, 2009). Doering and Chamberlain (1999) found that the operation of these control structures caused large and often rapid variations in salinity during various times of the year. Variable salinities could have deleterious impacts on the health of organisms in the Caloosahatchee River estuary.
Flow restriction along the Caloosahatchee has also been linked to surface-water eutrophication problems (Doering and Chamberlain, 1999; SFWMD, 2009) and bottom-sediment contamination (Fernandez and others, 1999). Sources of nutrients (nitrogen and phosphorous) that cause eutrophication are primarily from residential sources and agriculture, though wastewater-treatment-plant discharges can also play a major role (SFWMD, 2009). The pathway for many of these nutrients is by land runoff and direct discharge from stormwater drains. An often overlooked source of nutrients and other chemical constituents is from submarine groundwater discharge (SGD). SGD can be either a diffuse or point source (for example, submarine springs) of nutrients and other chemical constituents to coastal waters (Valiela and others, 1990; Swarzenski and others, 2001; 2006; 2007; 2008). SGD can be composed of either fresh or marine water or various mixed ratios of fresh and marine water (Martin and others, 2007). In coastal areas where water-table elevations (hydraulic gradients) are steep, such as in Hood Canal, Washington (Swarzenski and others, 2007; Simonds and others, 2008), groundwater entering the coastal marine waters can be fresh (~1-4 parts per thousand, ppt). SGD in coastal locations that have low relief (low hydraulic gradients) such as the study area or other locations in Florida are typically driven by tidal pumping (Reich and others, 2002; 2008; Swarzenski and others, 2008), and water advecting into surface water is composed of recirculated marine water mixed with either fresh or brackish groundwaters.
The importance of SGD in the delivery of nutrients and trace elements to coastal environments has been shown to be both beneficial and deleterious to ecosystem health (Valiela and others, 1990). The logical step in studying SGD is to map areas where SGD occurs. Methods such as continuous surface-water radon-222 (222Rn) mapping and electrical resistivity (continuous resistivity profiles, CRP) have been developed and used to identify potential SGD sites (Dulaiova and others, 2005; Swarzenski and others 2004; 2006; 2007; 2008; Reich and others, 2008). CRP data record subsurface, bulk-resistivity measurements to depths up to 25 meters (m). The bulk resistivity can be representative of changes in porewater salinity or in lithology (Reich and others, 2008; Swarzenski and others, 2008). Radon-222 (half-life = 3.28 days) is a natural tracer of groundwater, because sediments and rocks, containing uranium-bearing materials such as limestone and phosphatic material, continually produce 222Rn. Rn-222 (also referred to simply as radon) is an ideal tracer, because there is a constant source. Since radon is a gas, 222Rn does not build up in the surface water but rather evades directly to the atmosphere (Burnett and Dulaiova, 2003; Burnett and others, 2003; Dulaiova and Burnett, 2006).
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ofr20091273","usgsCitation":"Reich, C.D., 2010, Investigation of submarine groundwater discharge along the tidal reach of the Caloosahatchee River, southwest Florida: U.S. Geological Survey Open-File Report 2009-1273, Report: v, 20 p.; Appendix, https://doi.org/10.3133/ofr20091273.","productDescription":"Report: v, 20 p.; Appendix","onlineOnly":"N","additionalOnlineFiles":"Y","costCenters":[{"id":574,"text":"St. Petersburg Coastal and Marine Science Center","active":true,"usgs":true},{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"links":[{"id":423292,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_91390.htm","linkFileType":{"id":5,"text":"html"}},{"id":199286,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"},{"id":13425,"rank":2,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/of/2009/1273/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"Florida","otherGeospatial":"Caloosahatchee River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -81.6903,\n 26.7333\n ],\n [\n -82,\n 26.7333\n ],\n [\n -82,\n 26.5\n ],\n [\n -81.6903,\n 26.5\n ],\n [\n -81.6903,\n 26.7333\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4883e4b07f02db5180e8","contributors":{"authors":[{"text":"Reich, Christopher D. 0000-0002-2534-1456 creich@usgs.gov","orcid":"https://orcid.org/0000-0002-2534-1456","contributorId":900,"corporation":false,"usgs":true,"family":"Reich","given":"Christopher","email":"creich@usgs.gov","middleInitial":"D.","affiliations":[{"id":574,"text":"St. Petersburg Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":true,"id":304577,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":98159,"text":"fs20103002 - 2010 - Assessing the vulnerability of public-supply wells to contamination: Glacial aquifer system in Woodbury, Connecticut","interactions":[],"lastModifiedDate":"2021-11-04T18:14:32.80229","indexId":"fs20103002","displayToPublicDate":"2010-01-29T00:00:00","publicationYear":"2010","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":313,"text":"Fact Sheet","code":"FS","onlineIssn":"2327-6932","printIssn":"2327-6916","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2010-3002","title":"Assessing the vulnerability of public-supply wells to contamination: Glacial aquifer system in Woodbury, Connecticut","docAbstract":"This fact sheet highlights findings from the vulnerability study of a public-supply well in Woodbury, Connecticut. The well typically produces water at the rate of 72 gallons per minute from the glacial aquifer system in the Pomperaug River Basin. Water samples were collected at the public-supply well and at monitoring wells installed in or near the simulated zone of contribution to the supply well. Samples of untreated water from the public-supply wellhead contained several types of undesirable constituents, including 11 volatile organic compounds (VOCs), nitrate, pesticides, uranium, and radon. Most of these constituents were detected at concentrations below drinking-water standards, where such standards exist. Only concentrations of the VOC trichlorethylene exceeded the Maximum Contaminant Level (MCL) of 5 micrograms per liter (ug/L) established by U.S. Environmental Protection Agency for drinking water. Radon concentrations exceeded a proposed-but not finalized-MCL of 300 picocuries per liter (pCi/L). \n\nOverall, the study findings point to four main factors that affect the movement and fate of contaminants and the vulnerability of the public-supply well in Woodbury: (1) groundwater age (how long ago water entered, or recharged, the aquifer); (2) the percentage of recharge received through urban areas; (3) the percentage of recharge received through dry wells and their proximity to the public-supply well; and (4) natural geochemical processes occurring within the aquifer system; that is, processes that affect the amounts and distribution of chemical substances in aquifer sediments and groundwater.\n\nA computer-model simulation of groundwater flow to the public-supply well was used to estimate the age of water particles entering the well along the length of the well screen. About 90 percent of the simulated flow to the well consists of water that entered the aquifer 9 or fewer years ago. Such young water is vulnerable to contaminants resulting from human activities, as indicated by the solvents, fuel components, road salt, and septic-system leachate that were detected in the glacial aquifer system during the current study. Age-dating combined with chemical modeling suggests that less than 2 percent of water produced by the public-supply well is water from the deep bedrock that is \"old\" (water that recharged, or entered, the aquifer before 1952). Such a small percentage of old groundwater entering the public-supply well offers little potential for dilution of young waters containing contaminants from human activities. \n\nShallow groundwater that originated as recharge through urban areas generally had higher median concentrations and more detections of volatile organic compounds (VOCs) than did groundwater from the deep glacial deposits or fractured bedrock that originated mainly as recharge through agricultural and undeveloped land. Shallow groundwater was also found to be affected by road salt and septic-system leachate. A chemical mixing model indicates that up to 15 percent of nitrate in water from the supply well is likely from septic-system leachate.\n\nThe Connecticut Department of Public Health has identified several potential sources of contamination in the commercial area of Woodbury (several light industrial or commercial properties where hazardous materials and petroleum products are used and stored). To reduce stormwater runoff in the commercial area, water from the parking lots and pavement is channeled into dry wells-drains that shunt water directly into the aquifer system, bypassing the soil and unsaturated zones. A computer-model simulation of groundwater flow indicates that approximately 16 percent of the water produced by the public-supply well is derived from runoff captured by these drains. Traveltime for water from the dry wells to the public-supply well ranges from about 1.5 to less than 4 years. Dry wells have the potential to enhance contaminant movement to the supply well, suggesting that stormwater-control methods cannot be considered separately from groundwater quality—they are linked. \n\nWater-quality protection in this setting depends on the entire community. If residents and businesses take steps to reduce input of manmade contaminants to groundwater, a positive effect on quality of the supply-well water might begin to be seen in less than 10 years, owing to the short residence time of water in the aquifer.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/fs20103002","usgsCitation":"Jagucki, M.L., Brown, C., Starn, J.J., and Eberts, S., 2010, Assessing the vulnerability of public-supply wells to contamination: Glacial aquifer system in Woodbury, Connecticut: U.S. Geological Survey Fact Sheet 2010-3002, 6 p., https://doi.org/10.3133/fs20103002.","productDescription":"6 p.","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":451,"text":"National Water Quality Assessment Program","active":true,"usgs":true}],"links":[{"id":125804,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/fs_2010_3002.jpg"},{"id":13402,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/fs/2010/3002/","linkFileType":{"id":5,"text":"html"}},{"id":391387,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_91356.htm"}],"country":"United States","state":"Connecticut","city":"Woodbury","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -73.25202941894531,\n 41.49314949080981\n ],\n [\n -73.13529968261719,\n 41.49314949080981\n ],\n [\n -73.13529968261719,\n 41.57127917558171\n ],\n [\n -73.25202941894531,\n 41.57127917558171\n ],\n [\n -73.25202941894531,\n 41.49314949080981\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4abbe4b07f02db672a82","contributors":{"authors":[{"text":"Jagucki, Martha L. 0000-0003-3798-8393 mjagucki@usgs.gov","orcid":"https://orcid.org/0000-0003-3798-8393","contributorId":1794,"corporation":false,"usgs":true,"family":"Jagucki","given":"Martha","email":"mjagucki@usgs.gov","middleInitial":"L.","affiliations":[{"id":513,"text":"Ohio Water Science Center","active":true,"usgs":true}],"preferred":true,"id":304489,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Brown, Craig J.","contributorId":104450,"corporation":false,"usgs":true,"family":"Brown","given":"Craig J.","affiliations":[],"preferred":false,"id":304492,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Starn, J. Jeffrey","contributorId":101617,"corporation":false,"usgs":true,"family":"Starn","given":"J.","email":"","middleInitial":"Jeffrey","affiliations":[],"preferred":false,"id":304491,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Eberts, Sandra M. smeberts@usgs.gov","contributorId":2264,"corporation":false,"usgs":true,"family":"Eberts","given":"Sandra M.","email":"smeberts@usgs.gov","affiliations":[{"id":513,"text":"Ohio Water Science Center","active":true,"usgs":true}],"preferred":false,"id":304490,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70034370,"text":"70034370 - 2010 - Calibration and use of continuous heat-type automated seepage meters for submarine groundwater discharge measurements","interactions":[],"lastModifiedDate":"2012-03-12T17:21:47","indexId":"70034370","displayToPublicDate":"2010-01-01T00:00:00","publicationYear":"2010","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1587,"text":"Estuarine, Coastal and Shelf Science","active":true,"publicationSubtype":{"id":10}},"title":"Calibration and use of continuous heat-type automated seepage meters for submarine groundwater discharge measurements","docAbstract":"Submarine groundwater discharge (SGD) assessments were conducted both in the laboratory and at a field site in the northeastern Gulf of Mexico, using a continuous heat-type automated seepage meter (seepmeter). The functioning of the seepmeter is based on measurements of a temperature gradient in the water between downstream and upstream positions in its flow pipe. The device has the potential of providing long-term, high-resolution measurements of SGD. Using a simple inexpensive laboratory set-up, we have shown that connecting an extension cable to the seepmeter has a negligible effect on its measuring capability. Similarly, the observed influence of very low temperature (???3 ??C) on seepmeter measurements can be accounted for by conducting calibrations at such temperatures prior to field deployments. Compared to manual volumetric measurements, calibration experiments showed that at higher water flow rates (>28 cm day-1 or cm3 cm-2 day-1) an analog flowmeter overestimated flow rates by ???7%. This was apparently due to flow resistance, turbulence and formation of air bubbles in the seepmeter water flow tubes. Salinity had no significant effect on the performance of the seepmeter. Calibration results from fresh water and sea water showed close agreement at a 95% confidence level significance between the data sets from the two media (R2 = 0.98). Comparatively, the seepmeter SGD measurements provided data that are comparable to manually-operated seepage meters, the radon geochemical tracer approach, and an electromagnetic (EM) seepage meter. ?? 2009 Elsevier Ltd.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Estuarine, Coastal and Shelf Science","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/j.ecss.2009.12.001","issn":"02727714","usgsCitation":"Mwashote, B., Burnett, W.C., Chanton, J., Santos, I., Dimova, N., and Swarzenski, P., 2010, Calibration and use of continuous heat-type automated seepage meters for submarine groundwater discharge measurements: Estuarine, Coastal and Shelf Science, v. 87, no. 1, p. 1-10, https://doi.org/10.1016/j.ecss.2009.12.001.","startPage":"1","endPage":"10","numberOfPages":"10","costCenters":[],"links":[{"id":216559,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.ecss.2009.12.001"},{"id":244437,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"87","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f30fe4b0c8380cd4b59a","contributors":{"authors":[{"text":"Mwashote, B.M.","contributorId":27709,"corporation":false,"usgs":true,"family":"Mwashote","given":"B.M.","email":"","affiliations":[],"preferred":false,"id":445463,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Burnett, W. C.","contributorId":39779,"corporation":false,"usgs":false,"family":"Burnett","given":"W.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":445465,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Chanton, J.","contributorId":10641,"corporation":false,"usgs":true,"family":"Chanton","given":"J.","affiliations":[],"preferred":false,"id":445462,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Santos, I.R.","contributorId":94499,"corporation":false,"usgs":true,"family":"Santos","given":"I.R.","email":"","affiliations":[],"preferred":false,"id":445467,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Dimova, N.","contributorId":66051,"corporation":false,"usgs":true,"family":"Dimova","given":"N.","affiliations":[],"preferred":false,"id":445466,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Swarzenski, P.W. 0000-0003-0116-0578","orcid":"https://orcid.org/0000-0003-0116-0578","contributorId":29487,"corporation":false,"usgs":true,"family":"Swarzenski","given":"P.W.","affiliations":[],"preferred":false,"id":445464,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":98118,"text":"ofr20091257 - 2009 - Groundwater Quality in Central New York, 2007","interactions":[],"lastModifiedDate":"2012-03-08T17:16:29","indexId":"ofr20091257","displayToPublicDate":"2010-01-16T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":330,"text":"Open-File Report","code":"OFR","onlineIssn":"2331-1258","printIssn":"0196-1497","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2009-1257","title":"Groundwater Quality in Central New York, 2007","docAbstract":"Water samples were collected from 7 production wells and 28 private residential wells in central New York from August through December 2007 and analyzed to characterize the chemical quality of groundwater. Seventeen wells are screened in sand and gravel aquifers, and 18 are finished in bedrock aquifers. The wells were selected to represent areas of greatest groundwater use and to provide a geographical sampling from the 5,799-square-mile study area. Samples were analyzed for 6 physical properties and 216 constituents, including nutrients, major inorganic ions, trace elements, radionuclides, pesticides, volatile organic compounds, phenolic compounds, organic carbon, and 4 types of bacteria.\r\n\r\nResults indicate that groundwater used for drinking supply is generally of acceptable quality, although concentrations of some constituents or bacteria exceeded at least one drinking-water standard at several wells. The cations detected in the highest concentrations were calcium, magnesium, and sodium; anions detected in the highest concentrations were bicarbonate, chloride, and sulfate. The predominant nutrients were nitrate and ammonia, but no nutrients exceeded Maximum Contaminant Levels (MCLs). The trace elements barium, boron, lithium, and strontium were detected in every sample; the trace elements present in the highest concentrations were barium, boron, iron, lithium, manganese, and strontium. Fifteen pesticides, including seven pesticide degradates, were detected in water from 17 of the 35 wells, but none of the concentrations exceeded State or Federal MCLs. Sixteen volatile organic compounds were detected in water from 15 of the 35 wells.\r\n\r\nNine analytes and three types of bacteria were detected in concentrations that exceeded Federal and State drinking-water standards, which typically are identical. One sample had a water color that exceeded the U.S. Environmental Protection Agency (USEPA) Secondary Maximum Contaminant Level (SMCL) and the New York State MCL of 10 color units. Sulfate concentrations exceeded the USEPA SMCL and the New York State MCL of 250 milligrams per liter (mg/L) in two samples, and chloride concentrations exceeded the USEPA SMCL and the New York State MCL of 250 mg/L in two samples. Sodium concentrations exceeded the USEPA Drinking Water Health Advisory of 60 mg/L in eight samples. Iron concentrations exceeded the USEPA SMCL and the New York State MCL of 300 micrograms per liter (ug/L) in 10 filtered samples. Manganese exceeded the USEPA SMCL of 50 ug/L in 10 filtered samples and the New York State MCL of 300 ug/L in 1 filtered sample. Barium exceeded the MCL of 2,000 ug/L in one sample, and aluminum exceeded the SMCL of 50 ug/L in three samples. Radon-222 exceeded the proposed USEPA MCL of 300 picocuries per liter in 12 samples. One sample from a private residential well had a trichloroethene concentration of 50.8 ug/L, which exceeded the MCL of 5 ug/L. Any detection of coliform bacteria indicates a potential violation of New York State health regulations; total coliform bacteria were detected in 19 samples, and fecal coliform bacteria were detected in one sample. The plate counts for heterotrophic bacteria exceeded the MCL (500 colony-forming units per milliliter) in three samples.","language":"ENGLISH","publisher":"U.S. Geological Survey","doi":"10.3133/ofr20091257","collaboration":"Prepared in cooperation with the New York State Department of Environmental Conservation","usgsCitation":"Eckhardt, D., Reddy, J., and Shaw, S.B., 2009, Groundwater Quality in Central New York, 2007: U.S. Geological Survey Open-File Report 2009-1257, vi, 39 p., https://doi.org/10.3133/ofr20091257.","productDescription":"vi, 39 p.","onlineOnly":"N","additionalOnlineFiles":"N","temporalStart":"2007-08-01","temporalEnd":"2007-12-31","costCenters":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"links":[{"id":125636,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ofr_2009_1257.jpg"},{"id":13358,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/of/2009/1257/","linkFileType":{"id":5,"text":"html"}}],"geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -78,42 ], [ -78,44 ], [ -75,44 ], [ -75,42 ], [ -78,42 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a90e4b07f02db655990","contributors":{"authors":[{"text":"Eckhardt, David A.V.","contributorId":80233,"corporation":false,"usgs":true,"family":"Eckhardt","given":"David A.V.","affiliations":[],"preferred":false,"id":304223,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Reddy, J.E.","contributorId":32943,"corporation":false,"usgs":true,"family":"Reddy","given":"J.E.","email":"","affiliations":[],"preferred":false,"id":304221,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Shaw, Stephen B.","contributorId":40700,"corporation":false,"usgs":true,"family":"Shaw","given":"Stephen","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":304222,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":98060,"text":"sir20095051 - 2009 - Aquifer chemistry and transport processes in the zone of contribution to a public-supply well in Woodbury, Connecticut, 2002-06","interactions":[],"lastModifiedDate":"2019-08-13T12:29:12","indexId":"sir20095051","displayToPublicDate":"2009-12-19T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":334,"text":"Scientific Investigations Report","code":"SIR","onlineIssn":"2328-0328","printIssn":"2328-031X","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2009-5051","title":"Aquifer chemistry and transport processes in the zone of contribution to a public-supply well in Woodbury, Connecticut, 2002-06","docAbstract":"A glacial aquifer system in Woodbury, Connecticut, was studied to identify factors that affect the groundwater quality in the zone of contribution to a community public-supply well. Water samples were collected during 2002-06 from the public-supply well and from 35 monitoring wells in glacial stratified deposits, glacial till, and fractured bedrock. The glacial aquifer is vulnerable to contamination from a variety of sources due to the short groundwater residence times and the urban land use in the contributing recharge area to the public-supply well. The distribution and concentrations of pH, major and trace elements, stable isotope ratios, recharge temperatures, dissolved organic carbon (DOC), and volatile organic compounds (VOCs), and the oxidation-reduction (redox) conditions, were used to identify recharge source areas, aquifer source material, anthropogenic sources, chemical processes, and groundwater-flow paths from recharge areas to the public-supply well, PSW-1.\r\n\r\nThe major chemical sources to groundwater and the tracers or conditions used to identify them and their processes throughout the aquifer system include (1) bedrock and glacial stratified deposits and till, characterized by high pH and concentrations of sulfate (SO42-), bicarbonate, uranium (U), radon-222, and arsenic (As) relative to those of other wells, reducing redox conditions, enriched delta sulfur-34 (d34S) and delta carbon-13 (d13C) values, depleted delta oxygen-18 (d18O) and delta deuterium (dD) values, calcite near saturation, low recharge temperatures, and groundwater ages of more than about 9 years; (2) natural organic matter, either in sediments or in an upgradient riparian zone, characterized by high concentrations of DOC or manganese (Mn), low concentrations of dissolved oxygen (DO) and nitrate (NO3-), enriched d34S values, and depleted d18O and dD values; (3) road salt (halite), characterized by high concentrations of sodium (Na), chloride (Cl-), and calcium (Ca), and indicative chloride/bromide (Cl:Br) mass concentration ratios; (4) septic-system leachate, characterized by high concentrations of NO3-, DOC, Na, Cl-, Ca, and boron (B), delta nitrogen-15 (d15N) and d18O values, and indicative Cl:Br ratios; (5) organic solvent spills, characterized by detections of perchloroethene (PCE), trichloroethene (TCE), and 1,1-dichloroethene (1,1-DCE); (6) gasoline station spills, characterized by detections of fuel oxygenates and occasionally benzene; and (7) surface-water leakage, characterized by enriched d18O and dD values and sometimes high DOC and Mn-reducing conditions. Evaluation of Cl- concentrations and Cl:Br ratios indicates that most samples were composed of mixtures of groundwater and some component of road salt or septic-system leachate. Leachate from septic-tank drainfields can cause locally anoxic conditions with NO3- concentrations of as much as 19 milligrams per liter (mg/L as N) and may provide up to 15 percent of the nitrogen in water from well PSW-1, based on mixing calculations with d15N of NO3-.\r\n\r\nMost of the water that contributes to PSW-1 is young (less than 7 years) and derived from the glacial stratified deposits. Typically, groundwater is oxic, but localized reducing zones that result from abundances of organic matter can affect the mobilization of trace elements and the degradation of VOCs. Groundwater from fractured bedrock beneath the valley bottom, which is old (more than 50 years), and reflects a Mn-reducing to methanic redox environment, constitutes as much as 6 percent of water samples collected from monitoring wells screened at the bottom of the glacial aquifer. Dissolved As and U concentrations generally are near the minimum reporting level (MRL) (0.2 micrograms per liter or ?g/L and 0.04 ?g/L, respectively), but water from a few wells screened in glacial deposits, likely derived from underlying organic-rich Mesozoic rocks, contain As concentrations up to 7 ?g/L. At one location, concentrations of As and U were high ","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20095051","isbn":"9781411325470","usgsCitation":"Brown, C., Starn, J.J., Stollenwerk, K.G., Mondazzi, R.A., and Trombley, T.J., 2009, Aquifer chemistry and transport processes in the zone of contribution to a public-supply well in Woodbury, Connecticut, 2002-06: U.S. Geological Survey Scientific Investigations Report 2009-5051, xiv, 158 p., https://doi.org/10.3133/sir20095051.","productDescription":"xiv, 158 p.","onlineOnly":"N","additionalOnlineFiles":"N","temporalStart":"2002-01-01","temporalEnd":"2006-12-31","costCenters":[{"id":196,"text":"Connecticut Water Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":125771,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/sir_2009_5051.jpg"},{"id":13294,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/sir/2009/5051/","linkFileType":{"id":5,"text":"html"}}],"geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -74,40 ], [ -74,46 ], [ -69,46 ], [ -69,40 ], [ -74,40 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ac5e4b07f02db679fd1","contributors":{"authors":[{"text":"Brown, Craig J.","contributorId":104450,"corporation":false,"usgs":true,"family":"Brown","given":"Craig J.","affiliations":[],"preferred":false,"id":304042,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Starn, J. Jeffrey","contributorId":101617,"corporation":false,"usgs":true,"family":"Starn","given":"J.","email":"","middleInitial":"Jeffrey","affiliations":[],"preferred":false,"id":304041,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Stollenwerk, Kenneth G. kgstolle@usgs.gov","contributorId":578,"corporation":false,"usgs":true,"family":"Stollenwerk","given":"Kenneth","email":"kgstolle@usgs.gov","middleInitial":"G.","affiliations":[],"preferred":true,"id":304038,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Mondazzi, Remo A.","contributorId":77898,"corporation":false,"usgs":true,"family":"Mondazzi","given":"Remo","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":304040,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Trombley, Thomas J. trombley@usgs.gov","contributorId":1803,"corporation":false,"usgs":true,"family":"Trombley","given":"Thomas","email":"trombley@usgs.gov","middleInitial":"J.","affiliations":[{"id":196,"text":"Connecticut Water Science Center","active":true,"usgs":true}],"preferred":true,"id":304039,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":98056,"text":"ds479 - 2009 - Groundwater-quality data in the Antelope Valley study unit, 2008: Results from the California GAMA Program","interactions":[],"lastModifiedDate":"2022-07-20T12:12:41.782134","indexId":"ds479","displayToPublicDate":"2009-12-18T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":310,"text":"Data Series","code":"DS","onlineIssn":"2327-638X","printIssn":"2327-0271","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"479","title":"Groundwater-quality data in the Antelope Valley study unit, 2008: Results from the California GAMA Program","docAbstract":"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-control samples (blanks, replicates, and samples for matrix spikes) were collected at 12 percent of the wells, and the results for these samples were used to evaluate the quality of the data for the groundwater samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that contamination was not a noticeable source of bias in the data for the groundwater samples. Differences between replicate samples generally were within acceptable ranges, indicating acceptably low variability. Matrix spike recoveries were within acceptable ranges for most compoundsThis study did not evaluate the quality of water delivered to consumers; after withdrawal from the ground, water typically is treated, disinfected, or blended with other waters to maintain water quality. Regulatory thresholds apply to water that is served to the consumer, not to raw groundwater. However, to provide some context for the results, concentrations of constituents measured in the raw groundwater were compared with regulatory and non-regulatory health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CDPH) and thresholds established for aesthetic concerns (secondary maximum contaminant levels, SMCL-CA) by CDPH. Comparisons between data collected for this study and drinking-water thresholds are for illustrative purposes only, and are not indicative of compliance or non-compliance with drinking water standards.
Most constituents that were detected in groundwater samples were found at concentrations below drinking-water thresholds. Volatile organic compounds (VOCs) were detected in about one-half of the samples and pesticides detected in about one-third of the samples; all detections of these constituents were below health-based thresholds. Most detections of trace elements and nutrients in samples from ANT wells were below health-based thresholds. Exceptions include: one detection of nitrite plus nitrate as nitrogen (NO2+NO3) above the USEPA maximum contaminant level (MCL-US: 10 mg/L), five detections of arsenic above the MCL-US (6 μg/L), one detection of boron above the CDPH notification level (NL-CA: 1,000 μg/L), and two detections of vanadium above the NL-CA (50 μg/L). Most detections of radioactive constituents were below health-based thresholds. Exceptions include two detections of gross alpha radioactivity (72-hour and 30-day counts) above the MCL-US (15 pCi/L). Also, radon-222 was detected above the proposed MCL-US (300 pCi/L) in 14 grid wells and the understanding well, but no wells had detections above the proposed alternative MCL-US (4,000 pCi/L). Most of the samples from ANT wells had concentrations of major elements, total dissolved solids (TDS), and trace elements below the non-enforceable thresholds set for aesthetic concerns. Three samples contained sulfate and four samples contained total dissolved solids at concentrations above the SMCL-CA thresholds (250 mg/L and 500 mg/L, respectively). Two of the total dissolved solids detections were above the upper SMCL-CA (1,000 mg/L). Samples from four wells had field pH values above the SMCL-US (>pH 8.5). Field-measured specific conductance values were above the SMCL-CA (900 μS/cm at 25°C) at eight wells with four of these measurements above the upper SMCL-CA threshold (1,600 μS/cm at 25°C).
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ds479","collaboration":"Prepared in cooperation with the California State Water Resources Control Board","usgsCitation":"Schmitt, S., Milby Dawson, B.J., and Belitz, K., 2009, Groundwater-quality data in the Antelope Valley study unit, 2008: Results from the California GAMA Program: U.S. Geological Survey Data Series 479, x, 80 p., https://doi.org/10.3133/ds479.","productDescription":"x, 80 p.","temporalStart":"2008-01-01","temporalEnd":"2008-04-30","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":125856,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ds_479.jpg"},{"id":404079,"rank":2,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_89341.htm","linkFileType":{"id":5,"text":"html"}},{"id":13290,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/ds/479/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"California","otherGeospatial":"Antelope Valley study unit","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -118.7458,\n 34.3667\n ],\n [\n -117.5167,\n 34.3667\n ],\n [\n -117.5167,\n 35.3667\n ],\n [\n -118.7458,\n 35.3667\n ],\n [\n -118.7458,\n 34.3667\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a93e4b07f02db65881e","contributors":{"authors":[{"text":"Schmitt, Stephen J.","contributorId":85283,"corporation":false,"usgs":true,"family":"Schmitt","given":"Stephen J.","affiliations":[],"preferred":false,"id":304024,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Milby Dawson, Barbara J.","contributorId":57133,"corporation":false,"usgs":true,"family":"Milby Dawson","given":"Barbara","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":304023,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Belitz, Kenneth 0000-0003-4481-2345 kbelitz@usgs.gov","orcid":"https://orcid.org/0000-0003-4481-2345","contributorId":442,"corporation":false,"usgs":true,"family":"Belitz","given":"Kenneth","email":"kbelitz@usgs.gov","affiliations":[{"id":503,"text":"Office of Water Quality","active":true,"usgs":true},{"id":466,"text":"New England Water Science Center","active":true,"usgs":true},{"id":27111,"text":"National Water Quality Program","active":true,"usgs":true},{"id":376,"text":"Massachusetts Water Science Center","active":true,"usgs":true},{"id":451,"text":"National Water Quality Assessment Program","active":true,"usgs":true}],"preferred":true,"id":304022,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":98035,"text":"ds452 - 2009 - Groundwater quality data for the northern Sacramento Valley, 2007: Results from the California GAMA Program","interactions":[],"lastModifiedDate":"2022-07-20T21:52:01.334436","indexId":"ds452","displayToPublicDate":"2009-12-12T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":310,"text":"Data Series","code":"DS","onlineIssn":"2327-638X","printIssn":"2327-0271","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"452","title":"Groundwater quality data for the northern Sacramento Valley, 2007: Results from the California GAMA Program","docAbstract":"Groundwater quality in the approximately 1,180-square-mile Northern Sacramento Valley study unit (REDSAC) was investigated in October 2007 through January 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 REDSAC and to facilitate statistically consistent comparisons of groundwater quality throughout California. Samples were collected from 66 wells in Shasta and Tehama Counties. Forty-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 23 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 constituents. Naturally occurring isotopes (tritium, and carbon-14, and stable isotopes of nitrogen and oxygen in nitrate, 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 ground water. In total, over 275 constituents and field water-quality indicators were investigated.
Three types of quality-control samples (blanks, replicates, and sampmatrix spikes) were collected at approximately 8 to 11 percent of the wells, and the results for these samples were used to evaluate the quality of the data obtained from the groundwater samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that contamination was not a noticeable source of bias in the data for the groundwater samples. Differences between replicate samples were within acceptable ranges for nearly all compounds, indicating acceptably low variability. Matrix-spike recoveries were within acceptable ranges for most compounds.
This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, raw groundwater typically is treated, disinfected, or blended with other waters to maintain water quality. Regulatory thresholds apply to water that is served to the consumer, not to raw ground water. However, to provide some context for the results, concentrations of constituents measured in the raw groundwater were compared with regulatory and nonregulatory health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CDPH) and with aesthetic and technical thresholds established by CDPH. Comparisons between data collected for this study and drinking-water thresholds are for illustrative purposes only and do not indicate compliance or noncompliance with those thresholds.
The concentrations of most constituents detected in groundwater samples from REDSAC were below drinking-water thresholds. Volatile organic compounds (VOC) and pesticides were detected in less than one-quarter of the samples and were generally less than a hundredth of any health-based thresholds. NDMA was detected in one grid well above the NL-CA. Concentrations of all nutrients and trace elements in samples from REDSAC wells were below the health-based thresholds except those of arsenic in three samples, which were above the USEPA maximum contaminant level (MCL-US). However, none of these wells were public-supply wells. Concentrations of all radioactive constituents were below health-based thresholds except radon-222, which was detected above the proposed MCL-US of 300 pCi/L in samples from 11 grid wells. Most of the samples from REDSAC wells had concentrations of major elements, total dissolved solids, and trace elements below the non-enforceable thresholds set for aesthetic or technical concerns. A few samples contained iron, manganese, or pH at levels above the SMCL-CA or SMCL-US thresholds.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ds452","collaboration":"Prepared in cooperation with the California State Water Resources Control Board; A product of the California Groundwater Ambient Monitoring and Assessment (GAMA) Program","usgsCitation":"Bennett, P., Bennett, G.L., and Belitz, K., 2009, Groundwater quality data for the northern Sacramento Valley, 2007: Results from the California GAMA Program: U.S. Geological Survey Data Series 452, x, 91 p., https://doi.org/10.3133/ds452.","productDescription":"x, 91 p.","temporalStart":"2007-10-01","temporalEnd":"2008-01-31","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":125388,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ds_452.jpg"},{"id":404175,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_88758.htm","linkFileType":{"id":5,"text":"html"}},{"id":13251,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/ds/452/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"California","otherGeospatial":"northern Sacramento Valley","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -122.6272,\n 39.8914\n ],\n [\n -121.9456,\n 39.8914\n ],\n [\n -121.9456,\n 40.6667\n ],\n [\n -122.6272,\n 40.6667\n ],\n [\n -122.6272,\n 39.8914\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a96e4b07f02db65a1a1","contributors":{"authors":[{"text":"Bennett, Peter A.","contributorId":25824,"corporation":false,"usgs":true,"family":"Bennett","given":"Peter A.","affiliations":[],"preferred":false,"id":303964,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bennett, George L. V 0000-0002-6239-1604 georbenn@usgs.gov","orcid":"https://orcid.org/0000-0002-6239-1604","contributorId":1373,"corporation":false,"usgs":true,"family":"Bennett","given":"George","suffix":"V","email":"georbenn@usgs.gov","middleInitial":"L.","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":303963,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Belitz, Kenneth 0000-0003-4481-2345 kbelitz@usgs.gov","orcid":"https://orcid.org/0000-0003-4481-2345","contributorId":442,"corporation":false,"usgs":true,"family":"Belitz","given":"Kenneth","email":"kbelitz@usgs.gov","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true},{"id":27111,"text":"National Water Quality Program","active":true,"usgs":true},{"id":503,"text":"Office of Water Quality","active":true,"usgs":true},{"id":376,"text":"Massachusetts Water Science Center","active":true,"usgs":true},{"id":451,"text":"National Water Quality Assessment Program","active":true,"usgs":true}],"preferred":true,"id":303962,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":98017,"text":"sir20095147 - 2009 - Factors Affecting Water Quality in Domestic Wells in the Upper Floridan Aquifer, Southeastern United States, 1998-2005","interactions":[],"lastModifiedDate":"2012-02-02T00:15:08","indexId":"sir20095147","displayToPublicDate":"2009-12-01T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":334,"text":"Scientific Investigations Report","code":"SIR","onlineIssn":"2328-0328","printIssn":"2328-031X","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2009-5147","title":"Factors Affecting Water Quality in Domestic Wells in the Upper Floridan Aquifer, Southeastern United States, 1998-2005","docAbstract":"The Floridan aquifer system is a highly productive carbonate aquifer that provides drinking water to about 10 million people in Florida, Georgia, and South Carolina. Approximately 1.6 million people rely on domestic wells (privately owned household wells) for drinking water. Withdrawals of water from the Floridan aquifer system have increased by more than 500 percent from 630 million gallons per day (2.38 cubic meters per day) in 1950 to 4,020 million gallons per day (15.2 cubic meters per day) in 2000, largely due to increases in population, tourism, and agriculture production.\r\n\r\nWater samples were collected from 148 domestic wells in the Upper Floridan aquifer in Florida, Georgia, South Carolina, and Alabama during 1998-2005 as part of the U.S. Geological Survey (USGS) National Water-Quality Assessment Program. The wells were located in different hydrogeologic settings based on confinement of the Upper Floridan aquifer. Five networks of wells were sampled con-sisting of 28 to 30 wells each: two networks were in unconfined areas, two networks were in semiconfined areas, and one network was in the confined area. Physical properties and concentrations of major ions, trace elements, nutrients, radon, and organic compounds (volatile organic compounds and pesticides) were measured in water samples. Concentrations were compared to water-quality benchmarks for human health, either U.S. Environmental Protection Agency (USEPA) Maximum Contaminant Levels (MCLs) for public water supplies or USGS Health-Based Screening Levels (HBSLs). The MCL for fluoride of 4 milligrams per liter (mg/L) was exceeded for two samples (about 1 percent of samples). A proposed MCL for radon of 300 picocuries per liter was exceeded in about 40 percent of samples.\r\n\r\nNitrate concentrations in the Upper Floridan aquifer ranged from less than the laboratory reporting level of 0.06 to 8 mg/L, with a median nitrate concentration less than 0.06 mg/L (as nitrogen). Nitrate concentrations did not exceed the MCL of 10 mg/L. Statistical comparisons indicated that median nitrate concentrations were significantly different by degree of confinement where the highest median nitrate concentration was 1.46 mg/L for 58 samples from unconfined areas, and by network, where the highest median nitrate concentration was 2.43 mg/L in 28 samples from unconfined areas in southwestern Georgia. Nitrate concentrations in unconfined areas were positively correlated to: (1) the percentage of agricultural land use around the well, (2) the amount of nitrogen fertilizer applied, and (3) the dissolved oxygen concentrations in groundwater.\r\n\r\nVolatile organic compounds (VOCs) were detected in about 63 percent of all samples. Chloroform, carbon disulfide, and 1,2-dichloropropane were the most frequently detected VOCs. Chloroform, a byproduct of water chlorination, was most frequently detected in unconfined urban areas. Carbon disulfide, a solvent, was most frequently detected in confined areas in southeastern Georgia. Pesticides were detected in about 21 percent of all samples, but were detected in about 69 percent of the 28 samples from unconfined areas in southwestern Georgia. The herbicides atrazine, deethylatrazine, and metolachlor were the most frequently detected pesticides.\r\n","language":"ENGLISH","publisher":"U.S. Geological Survey","doi":"10.3133/sir20095147","collaboration":"Prepared as part of the\r\nNational Water-Quality Assessment Program","usgsCitation":"Berndt, M., Crandall, C.A., Deacon, M., Embry, T.L., and Howard, R.S., 2009, Factors Affecting Water Quality in Domestic Wells in the Upper Floridan Aquifer, Southeastern United States, 1998-2005: U.S. Geological Survey Scientific Investigations Report 2009-5147, ix, 39 p., https://doi.org/10.3133/sir20095147.","productDescription":"ix, 39 p.","onlineOnly":"N","additionalOnlineFiles":"Y","costCenters":[{"id":281,"text":"Florida Integrated Science Center-Tallahassee","active":false,"usgs":true}],"links":[{"id":125795,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/sir_2009_5147.jpg"},{"id":13406,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/sir/2009/5147/","linkFileType":{"id":5,"text":"html"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e49d8e4b07f02db5df8be","contributors":{"authors":[{"text":"Berndt, Marian P.","contributorId":45296,"corporation":false,"usgs":true,"family":"Berndt","given":"Marian P.","affiliations":[],"preferred":false,"id":303899,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Crandall, Christy A. crandall@usgs.gov","contributorId":1091,"corporation":false,"usgs":true,"family":"Crandall","given":"Christy","email":"crandall@usgs.gov","middleInitial":"A.","affiliations":[],"preferred":true,"id":303897,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Deacon, Michael mdeacon@usgs.gov","contributorId":1213,"corporation":false,"usgs":true,"family":"Deacon","given":"Michael","email":"mdeacon@usgs.gov","affiliations":[],"preferred":true,"id":303898,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Embry, Teresa L.","contributorId":61503,"corporation":false,"usgs":true,"family":"Embry","given":"Teresa","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":303900,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Howard, Rhonda S.","contributorId":66804,"corporation":false,"usgs":true,"family":"Howard","given":"Rhonda","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":303901,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":97991,"text":"ds432 - 2009 - Groundwater quality data for the Tahoe-Martis study unit, 2007: Results from the California GAMA Program","interactions":[],"lastModifiedDate":"2022-07-19T20:12:12.143918","indexId":"ds432","displayToPublicDate":"2009-11-12T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":310,"text":"Data Series","code":"DS","onlineIssn":"2327-638X","printIssn":"2327-0271","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"432","title":"Groundwater quality data for the Tahoe-Martis study unit, 2007: Results from the California GAMA Program","docAbstract":"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 results obtained from these samples were used to evaluate the quality of the data for the groundwater samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that data for the groundwater samples were not compromised by possible contamination during sample collection, handling or analysis. Differences between replicate samples were within acceptable ranges. Matrix spike recoveries were within acceptable ranges for most compounds.
This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, raw water typically is treated, disinfected, or blended with other waters to maintain water quality. Regulatory thresholds apply to water that is served to the consumer, not to raw groundwater. However, to provide some context for the results, concentrations of constituents measured in the raw groundwater were compared with regulatory and nonregulatory health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and the California Department of Public Health (CDPH), and with aesthetic and technical thresholds established by CDPH. Comparisons between data collected for this study and drinking-water thresholds are for illustrative purposes only and do not indicate of compliance or noncompliance with regulatory thresholds.
The concentrations of most constituents detected in groundwater samples from the Tahoe–Martis wells were below drinking-water thresholds. Organic compounds (VOCs and pesticides) were detected in about 40 percent of the samples from grid wells, and most concentrations were less than 1/100th of regulatory and nonregulatory health-based thresholds, although the conentration of perchloroethene in one sample was above the USEPA maximum contaminant level (MCL-US). Concentrations of all trace elements and nutrients in samples from grid wells were below regulatory and nonregulatory health-based thresholds, with five exceptions. Concentrations of arsenic were above the MCL-US in 20 percent of the samples from grid wells. Gross alpha particle activity (MCL-US), boron (CDPH notification level, NL-CA), and molybdenum (USEPA lifetime health advisory, HAL-US) were each detected above thresholds in two of the samples from grid wells, and radon (proposed alternative MCL-US) was detected above the threshold in one sample from a grid well. Most of the samples from Tahoe–Martis grid wells had concentrations of major elements, total dissolved solids, and trace elements below the CDPH secondary maximum contaminant levels, nonenforceable thresholds set for aesthetic and technical concerns. Fifteen percent of the samples from grid wells contained iron, manganese, or total dissolved solids at concentrations above these levels.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ds432","collaboration":"Prepared in cooperation with the California State Water Resources Control Board","usgsCitation":"Fram, M.S., Munday, C., and Belitz, K., 2009, Groundwater quality data for the Tahoe-Martis study unit, 2007: Results from the California GAMA Program: U.S. Geological Survey Data Series 432, x, 89 p., https://doi.org/10.3133/ds432.","productDescription":"x, 89 p.","temporalStart":"2007-06-01","temporalEnd":"2007-09-30","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":125385,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ds_432.jpg"},{"id":404072,"rank":2,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_87733.htm","linkFileType":{"id":5,"text":"html"}},{"id":13167,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/ds/432/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"California, Nevada","otherGeospatial":"Tahoe-Martis study unit","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -120.3194,\n 38.7617\n ],\n [\n -119.8833,\n 38.7617\n ],\n [\n -119.8833,\n 39.425\n ],\n [\n -120.3194,\n 39.425\n ],\n [\n -120.3194,\n 38.7617\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a96e4b07f02db65a1b0","contributors":{"authors":[{"text":"Fram, Miranda S. 0000-0002-6337-059X mfram@usgs.gov","orcid":"https://orcid.org/0000-0002-6337-059X","contributorId":1156,"corporation":false,"usgs":true,"family":"Fram","given":"Miranda","email":"mfram@usgs.gov","middleInitial":"S.","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":303821,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Munday, Cathy","contributorId":57538,"corporation":false,"usgs":true,"family":"Munday","given":"Cathy","affiliations":[],"preferred":false,"id":303822,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Belitz, Kenneth 0000-0003-4481-2345 kbelitz@usgs.gov","orcid":"https://orcid.org/0000-0003-4481-2345","contributorId":442,"corporation":false,"usgs":true,"family":"Belitz","given":"Kenneth","email":"kbelitz@usgs.gov","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true},{"id":27111,"text":"National Water Quality Program","active":true,"usgs":true},{"id":451,"text":"National Water Quality Assessment Program","active":true,"usgs":true},{"id":503,"text":"Office of Water Quality","active":true,"usgs":true},{"id":376,"text":"Massachusetts Water Science Center","active":true,"usgs":true}],"preferred":true,"id":303820,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":97978,"text":"ofr20091240 - 2009 - Ground-Water Quality in the Upper Hudson River Basin, New York, 2007","interactions":[],"lastModifiedDate":"2012-03-08T17:16:30","indexId":"ofr20091240","displayToPublicDate":"2009-11-10T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":330,"text":"Open-File Report","code":"OFR","onlineIssn":"2331-1258","printIssn":"0196-1497","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"2009-1240","title":"Ground-Water Quality in the Upper Hudson River Basin, New York, 2007","docAbstract":"Water samples were collected from 25 production and domestic wells in the Upper Hudson River Basin (north of the Federal Dam at Troy, N.Y.) from August through November 2007 to characterize the ground-water quality. The Upper Hudson River Basin covers 4,600 square miles in upstate New York, Vermont, and Massachusetts; the study area encompasses the 4,000 square miles that lie within New York. The basin is underlain by crystalline and sedimentary bedrock, including gneiss, shale, and slate; some sandstone and carbonate rocks are present locally. The bedrock in some areas is overlain by surficial deposits of saturated sand and gravel. Of the 25 wells sampled, 13 were finished in sand and gravel deposits, and 12 were finished in bedrock. The samples were collected and processed by standard U.S. Geological Survey procedures and were analyzed for 225 physical properties and constituents, including major ions, nutrients, trace elements, radon-222, pesticides, volatile organic compounds (VOCs), and indicator bacteria.\r\n\r\nWater quality in the study area is generally good, but concentrations of some constituents exceeded current or proposed Federal or New York State drinking-water standards; these were: color (1 sample), pH (2 samples), sodium (5 samples), nitrate plus nitrite (2 samples), aluminum (3 samples), iron (1 sample), manganese (7 samples), radon-222 (11 samples), and bacteria (1 sample). Dissolved-oxygen concentrations in samples from wells finished in sand and gravel [median 5.4 milligrams per liter (mg/L)] were greater than those from wells finished in bedrock (median 0.4 mg/L). The pH of all samples was typically neutral or slightly basic (median 7.6); the median water temperature was 9.7 deg C. The ions with the highest concentrations were bicarbonate (median 123 mg/L) and calcium (median 33.9 mg/L). Ground water in the basin is generally soft to moderately hard (less than or equal to 120 mg/L as CaCO3) (median hardness 110 mg/L as CaCO3). Concentrations of nitrate plus nitrite in samples from sand and gravel wells (median concentration 0.47 mg/L as nitrogen) were generally higher than those in samples from bedrock wells (median estimated 0.05 mg/L as nitrogen), and concentrations in two samples exceeded established drinking-water standards for nitrate (10 mg/L as nitrogen). The trace elements with the highest concentrations were strontium [median 217 micrograms per liter (ug/L)] and iron (median 39 ug/L). The highest radon-222 activities were in samples from bedrock wells [maximum 2,930 picocuries per liter (pCi/L)] and 44 percent of all samples exceeded a proposed U.S. Environmental Protection Agency (USEPA) drinking-water standard of 300 pCi/L. Ten pesticides and pesticide degradates were detected among 11 samples at concentrations of 1.47 ug/L or less; most were herbicides or their degradates. Six VOCs were detected among 10 samples at concentrations of 4.2 ug/L or less; these included three trihalomethanes and methyl tert-butyl ether, tetrachloroethene, and toluene. Most detections were in samples from sand and gravel wells and none exceeded drinking-water standards. Total coliform bacteria were detected in only one sample, and fecal coliform bacteria, including Escherichia coli, were not detected in any sample.","language":"ENGLISH","publisher":"U.S. Geological Survey","doi":"10.3133/ofr20091240","collaboration":"Prepared in cooperation with the New York State Department of Environmental Conservation","usgsCitation":"Nystrom, E.A., 2009, Ground-Water Quality in the Upper Hudson River Basin, New York, 2007: U.S. Geological Survey Open-File Report 2009-1240, vi, 39 p., https://doi.org/10.3133/ofr20091240.","productDescription":"vi, 39 p.","onlineOnly":"Y","temporalStart":"2007-01-01","temporalEnd":"2007-12-31","costCenters":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"links":[{"id":125513,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ofr_2009_1240.jpg"},{"id":13156,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/of/2009/1240/","linkFileType":{"id":5,"text":"html"}}],"geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -74.75,42.5 ], [ -74.75,44.25 ], [ -73,44.25 ], [ -73,42.5 ], [ -74.75,42.5 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ab0e4b07f02db66d4db","contributors":{"authors":[{"text":"Nystrom, Elizabeth A. 0000-0002-0886-3439 nystrom@usgs.gov","orcid":"https://orcid.org/0000-0002-0886-3439","contributorId":1072,"corporation":false,"usgs":true,"family":"Nystrom","given":"Elizabeth","email":"nystrom@usgs.gov","middleInitial":"A.","affiliations":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"preferred":true,"id":303787,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":97914,"text":"ds440 - 2009 - Groundwater quality data in the Mojave study unit, 2008: Results from the California GAMA Program","interactions":[],"lastModifiedDate":"2022-07-19T20:16:33.323921","indexId":"ds440","displayToPublicDate":"2009-10-10T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":310,"text":"Data Series","code":"DS","onlineIssn":"2327-638X","printIssn":"2327-0271","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"440","title":"Groundwater quality data in the Mojave study unit, 2008: Results from the California GAMA Program","docAbstract":"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 ground water. In total, over 230 constituents and water-quality indicators (field parameters) were investigated.
Three types of quality-control samples (blanks, replicates, and matrix spikes) each were collected at approximately 5–8 percent of the wells, and the results for these samples were used to evaluate the quality of the data for the groundwater samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that contamination was not a significant source of bias in the data for the groundwater samples. Differences between replicate samples generally were within acceptable ranges, indicating acceptable analytical reproducibility. Matrix spike recoveries were within acceptable ranges for most compounds.
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, or blended with other waters to maintain water quality. Regulatory thresholds apply to water that is served to the consumer, not to untreated ground water. However, to provide some context for the results, concentrations of constituents measured in the untreated ground water were compared with regulatory and non-regulatory health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CDPH) and thresholds established for aesthetic and technical concerns by CDPH. Comparisons between data collected for this study and thresholds for drinking-water are for illustrative purposes only, and are not indicative of compliance or non-compliance with those thresholds.
Most constituents that were detected in groundwater samples in the 59 wells in MOJO were found at concentrations below drinking-water thresholds. In MOJO’s 52 grid wells, volatile organic compounds (VOCs) were detected in 40 percent of the wells, and pesticides and pesticide degradates were detected in 23 percent of the grid wells. Results for health-based thresholds in MOJO grid wells showed that all of the detections of organic compounds in samples from MOJO grid wells were below health-based thresholds, with the exception of a single detection of NDMA above the California Department of Public Health notification level (NL-CA).
Trace elements and radioactive constituents were sampled for at 19 MOJO grid wells and most detections were below health-based thresholds. Exceptions include: six detections of arsenic above the USEPA maximum contaminant level (MCL-US), two detections of boron and one detection of vanadium above the NL-CA, one detection each of molybdenum and strontium that were above the USEPA lifetime health advisory level (HAL-US), and one detection of fluoride just above the MCL-CA of 2 µg/L. Most detections of radioactive constituents in the MOJO grid wells were below health-based thresholds, with the exception of one detection of gross alpha radioactivity (72-hour count and 30-day count) above the MCL-CA, and 17 grid wells (of 19 sampled) that had activities of radon-222 above the proposed MCL-US of 300 pCi/L, but all were below the proposed alternative MCL-US of 4,000 pCi/L.
All of the samples collected from the 19 MOJO grid wells for trace elements, and most of the samples for major ions and total dissolved solids (TDS), had measured concentrations below the non-enforceable thresholds set for aesthetic concerns. Four grid wells had TDS concentrations above the California Department of Public Health secondary maximum contaminant level (SMCL-CA) recommended threshold of 500 mg/L, and three of these wells were also above the SMCL-CA upper threshold of 1,000 mg/L. Four grid wells (of 19 sampled) had sulfate measured at concentrations above the recommended SMCL-CA threshold of 250 mg/L, and one of these detections was also above the upper SMCL-CA threshold of 500 mg/L. One grid well had chloride levels at a concentration above the upper SMCL-CA threshold of 500 mg/L. Eleven grid wells (of 52 sampled) had pH values outside of the SMCL-US range for pH.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ds440","collaboration":"Prepared in cooperation with the California State Water Resources Control Board; A product of the California Groundwater Ambient Monitoring and Assessment (GAMA) Program","usgsCitation":"Mathany, T., and Belitz, K., 2009, Groundwater quality data in the Mojave study unit, 2008: Results from the California GAMA Program: U.S. Geological Survey Data Series 440, x, 81 p., https://doi.org/10.3133/ds440.","productDescription":"x, 81 p.","temporalStart":"2008-02-01","temporalEnd":"2008-04-30","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":118585,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ds_440.jpg"},{"id":13086,"rank":100,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/ds/440/","text":"Index page","linkFileType":{"id":5,"text":"html"}},{"id":360778,"rank":3,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/ds/440/pdf/ds440.pdf","text":"Report","size":"12.3 MB","linkFileType":{"id":1,"text":"pdf"}}],"country":"United States","state":"California","otherGeospatial":"Mojave study unit","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -117.7333,\n 34.2833\n ],\n [\n -116.35,\n 34.2833\n ],\n [\n -116.35,\n 35.0708\n ],\n [\n -117.7333,\n 35.0708\n ],\n [\n -117.7333,\n 34.2833\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a95e4b07f02db659f54","contributors":{"authors":[{"text":"Mathany, Timothy M. 0000-0002-4747-5113","orcid":"https://orcid.org/0000-0002-4747-5113","contributorId":99949,"corporation":false,"usgs":true,"family":"Mathany","given":"Timothy M.","affiliations":[],"preferred":false,"id":303577,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Belitz, Kenneth 0000-0003-4481-2345 kbelitz@usgs.gov","orcid":"https://orcid.org/0000-0003-4481-2345","contributorId":442,"corporation":false,"usgs":true,"family":"Belitz","given":"Kenneth","email":"kbelitz@usgs.gov","affiliations":[{"id":376,"text":"Massachusetts Water Science Center","active":true,"usgs":true},{"id":451,"text":"National Water Quality Assessment Program","active":true,"usgs":true},{"id":27111,"text":"National Water Quality Program","active":true,"usgs":true},{"id":466,"text":"New England Water Science Center","active":true,"usgs":true},{"id":503,"text":"Office of Water Quality","active":true,"usgs":true}],"preferred":true,"id":303576,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":97840,"text":"ds463 - 2009 - Groundwater-quality data in the South Coast Interior Basins study unit, 2008: Results from the California GAMA Program","interactions":[],"lastModifiedDate":"2022-07-19T21:01:03.316013","indexId":"ds463","displayToPublicDate":"2009-09-22T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":310,"text":"Data Series","code":"DS","onlineIssn":"2327-638X","printIssn":"2327-0271","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"463","title":"Groundwater-quality data in the South Coast Interior Basins study unit, 2008: Results from the California GAMA Program","docAbstract":"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], and radioactive constituents [gross alpha and gross beta radioactivity and radon-222]. Naturally occurring isotopes [stable isotopes of hydrogen, oxygen, and carbon, and activities of tritium and carbon-14] and dissolved noble gases also were measured to help identify the sources and ages of the sampled groundwater. In total, 288 constituents and water-quality indicators (field parameters) were investigated.
Three types of quality-control samples (blanks, replicates, and matrix spikes) each were collected at approximately 4–11 percent of the wells, and the results for these samples were used to evaluate the quality of the data for the groundwater samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that contamination was not a significant source of bias in the data obtained from the groundwater samples. Differences between replicate samples generally were less than 10 percent relative standard deviation, indicating acceptable analytical reproducibility. Matrix spike recoveries were within the acceptable range (70 to 130 percent) for most compounds.
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 thresholds 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 groundwater were compared with regulatory and nonregulatory health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CDPH), and to nonregulatory thresholds established for aesthetic and technical concerns by CDPH. Comparisons between data collected for this study and thresholds for drinking water are for illustrative purposes only, and are not indicative of compliance or noncompliance with those thresholds.
Most inorganic constituents that were detected in groundwater samples from the 35 grid wells in the SCI study unit were found at concentrations below drinking-water thresholds; additionally, all detections of organic constituents in SCI grid well samples were below health-based thresholds.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ds463","collaboration":"Prepared in cooperation with the California State Water Resources Control Board","usgsCitation":"Mathany, T., Kulongoski, J., Ray, M.C., and Belitz, K., 2009, Groundwater-quality data in the South Coast Interior Basins study unit, 2008: Results from the California GAMA Program: U.S. Geological Survey Data Series 463, xii, 83 p., https://doi.org/10.3133/ds463.","productDescription":"xii, 83 p.","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":118588,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ds_463.jpg"},{"id":13013,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/ds/463/","linkFileType":{"id":5,"text":"html"}},{"id":404082,"rank":2,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_87388.htm","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"California","otherGeospatial":"South Coast Interior Basins study unit","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -121.9833,\n 37.5833\n ],\n [\n -121.650,\n 37.5833\n ],\n [\n -121.650,\n 37.7833\n ],\n [\n -121.9833,\n 37.7833\n ],\n [\n -121.9833,\n 37.5833\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a94e4b07f02db658d8f","contributors":{"authors":[{"text":"Mathany, Timothy M. 0000-0002-4747-5113","orcid":"https://orcid.org/0000-0002-4747-5113","contributorId":99949,"corporation":false,"usgs":true,"family":"Mathany","given":"Timothy M.","affiliations":[],"preferred":false,"id":303311,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kulongoski, Justin T. 0000-0002-3498-4154","orcid":"https://orcid.org/0000-0002-3498-4154","contributorId":94750,"corporation":false,"usgs":true,"family":"Kulongoski","given":"Justin T.","affiliations":[],"preferred":false,"id":303310,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Ray, Mary C.","contributorId":65945,"corporation":false,"usgs":true,"family":"Ray","given":"Mary","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":303309,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Belitz, Kenneth 0000-0003-4481-2345 kbelitz@usgs.gov","orcid":"https://orcid.org/0000-0003-4481-2345","contributorId":442,"corporation":false,"usgs":true,"family":"Belitz","given":"Kenneth","email":"kbelitz@usgs.gov","affiliations":[{"id":503,"text":"Office of Water Quality","active":true,"usgs":true},{"id":376,"text":"Massachusetts Water Science Center","active":true,"usgs":true},{"id":451,"text":"National Water Quality Assessment Program","active":true,"usgs":true},{"id":466,"text":"New England Water Science Center","active":true,"usgs":true},{"id":27111,"text":"National Water Quality Program","active":true,"usgs":true}],"preferred":true,"id":303308,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":97829,"text":"ds314 - 2009 - Selected ground-water-quality data in Pennsylvania - 1979-2006","interactions":[],"lastModifiedDate":"2017-06-22T08:33:24","indexId":"ds314","displayToPublicDate":"2009-09-17T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":310,"text":"Data Series","code":"DS","onlineIssn":"2327-638X","printIssn":"2327-0271","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"314","title":"Selected ground-water-quality data in Pennsylvania - 1979-2006","docAbstract":"This study, by the U.S. Geological Survey (USGS) in cooperation with the Pennsylvania Department of Environmental Protection (PADEP), provides a compilation of ground-water-quality data for a 28-year period (January 1, 1979, through December 31, 2006) based on water samples from wells and springs. The data are from 14 source agencies or programs—Borough of Carroll Valley, Chester County Health Department, Montgomery County Health Department, Pennsylvania Department of Agriculture, Pennsylvania Department of Environmental Protection 2002 Pennsylvania Water-Quality Assessment, Pennsylvania Department of Environmental Protection Agency Act 537 Sewage Facilities Program, Pennsylvania Department of Environmental Protection-Ambient and Fixed Station Network, Pennsylvania Department of Environmental Protection–North-Central Region, Pennsylvania Department of Environmental Protection–South-Central Region, Pennsylvania Drinking Water Information System, Pennsylvania Topographic and Geologic Survey, Susquehanna River Basin Commission, U.S. Environmental Protection Agency, and the U.S. Geological Survey. The ground-water-quality data from the different source agencies or programs varied in type and number of analyses; however, the analyses are represented by 11 major analyte groups: antibiotics, major ions, microorganisms (bacteria, viruses, and other microorganisms), minor ions (including trace elements), nutrients (predominantly nitrate and nitrite as nitrogen), pesticides, pharmaceuticals, radiochemicals (predominantly radon or radium), volatiles (volatile organic compounds), wastewater compounds, and water characteristics (field measurements, predominantly field pH, field specific conductance, and hardness). For the USGS and the PADEP–North-Central Region, the pesticide analyte group was broken down into fungicides, herbicides, and insecticides.
Summary maps show the areal distribution of wells and springs with ground-water-quality data statewide by source agency or program. Summary data tables by source agency or program provide information on the number of wells and springs and samples collected for each of the 35 watersheds and analyte groups.
The number of wells and springs sampled for ground-water-quality data varies considerably across Pennsylvania. Of the 24,772 wells and springs sampled, the greatest concentration of wells and springs is in the southeast (Berks, Bucks, Chester, Delaware, Lancaster, Montgomery, and Philadelphia Counties) and in the northwest (Erie County). The number of wells and springs sampled is relatively sparse in north-central (Cameron, Elk, Forest, McKean, Potter, and Warren Counties) Pennsylvania. Little to no data are available for approximately one-fourth of the state. Nutrients and water characteristics were the most frequently sampled major analyte groups—43,025 and 30,583 samples, respectively. Minor ions and major ions were the next most frequently sampled major analyte groups–26,972 and 13,115 samples, respectively. For the remaining 10 major analyte groups, the number of samples collected ranged from a low of 24 samples (antibiotic compounds) to a high of approximately 4,674 samples (microorganisms).
The number of samples that exceeded a maximum contaminant level (MCL) or secondary maximum contaminant level (SMCL) by major analyte group also varied. Of the 4,674 samples in the microorganism analyte group, 50.2 percent had water that exceeded an MCL. Of the 4,528 samples collected and analyzed for volatile organic compounds, 23.5 percent exceeded an MCL. Other major analyte groups that frequently exceeded MCLs or SMCLs included major ions (18,343 samples and a 27.7 percent exceedence), minor ions (26,972 samples, 44.7 percent exceedence), pesticides (4,868 samples, 0.7 percent exceedence), water characteristics (30,583 samples, 19.3 percent exceedence), and radiochemicals (1,866 samples, 9.6 percent exceedence). Samples collected and analyzed for antibiotics (24 samples), fungicides (1,273 samples), herbicides (1,470 samples), insecticides (1,424 samples), nutrients (43,025 samples), pharmaceuticals (28 samples), and wastewater compounds (328 samples) had the lowest exceedences of 0.0, 2.4, 1.2, <1.0, 8.3, 0.0, and <1.0 percent, respectively.
Carbonate aquifers are an important source of water in the United States; however, these aquifers can be particularly susceptible to contamination from the land surface. The U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program collected samples from wells and springs in 12 carbonate aquifers across the country during 1993–2005; water-quality results for 1,042 samples were available to assess the factors affecting ground-water quality. These aquifers represent a wide range of climate, land-use types, degrees of confinement, and other characteristics that were compared and evaluated to assess the effect of those factors on water quality. Differences and similarities among the aquifers were also identified. Samples were analyzed for major ions, radon, nutrients, 47 pesticides, and 54 volatile organic compounds (VOCs).
Geochemical analysis helped to identify dominant processes that may contribute to the differences in aquifer susceptibility to anthropogenic contamination. Differences in concentrations of dissolved oxygen and dissolved organic carbon and in ground-water age were directly related to the occurrence of anthropogenic contaminants. Other geochemical indicators, such as mineral saturation indexes and calcium-magnesium molar ratio, were used to infer residence time, an indirect indicator of potential for anthropogenic contamination. Radon exceeded the U.S. Environmental Protection Agency proposed Maximum Contaminant Level (MCL) of 300 picocuries per liter in 423 of 735 wells sampled, of which 309 were drinking-water wells.
In general, land use, oxidation-reduction (redox) status, and degree of aquifer confinement were the most important factors affecting the occurrence of anthropogenic contaminants. Although none of these factors individually accounts for all the variation in water quality among the aquifers, a combination of these characteristics accounts for the majority of the variation. Unconfined carbonate aquifers that had high percentages of urban or agricultural land, or a combination of both, had higher concentrations and higher frequency of detections for most of the anthropogenic contaminants than areas with other combinations of land use and degree of aquifer confinement. Redox status is an indicator of more recently recharged water and affects the fate of some contaminants.
Median concentrations of nitrate were highest in the Valley and Ridge and Piedmont aquifers and lowest in the Biscayne and Silurian-Devonian/Upper carbonate aquifers. Nitrate concentrations were significantly higher in unconfined aquifers than in confined aquifers and semiconfined/mixed confined aquifers (wells in aquifers with breached confining layers or wells open to both a confined and an unconfined aquifer). Water recharged after 1953 had significantly higher concentrations of nitrate than water recharged prior to 1953. Redox status was also a key factor affecting nitrate concentrations; in recently recharged waters, samples in oxic waters had significantly higher concentrations of nitrate than anoxic waters, regardless of land use in the area around the well. Samples from 54 wells (5 percent) exceeded the U.S. Environmental Protection Agency MCL of 10 mg/L for nitrate in drinking water. Most of the samples exceeding the drinking-water standard (52 samples, or 5 percent) were in domestic supply wells in agricultural areas. The Piedmont and Valley and Ridge aquifers had the largest number of samples (45) exceeding the MCL; in the remaining aquifers only 9 samples had concentrations of nitrate that exceeded the MCL (about 1 percent). None of the water recharged prior to 1953 and only a single sample from a confined aquifer had nitrate concentrations that exceeded 10 mg/L as N.
Wells were sampled for a minimum of 47 pesticides. Detection frequencies and comparisons varied depending on the assessment level used. At least 1 of the 47 pesticides was detected at 510 (50 percent) of the 1,027 sites where pesticide data were available using the ‘all detections’ assessment level—that is, including any quantified detection as well as any estimated values where the compound was definitively detected. Multiple pesticides were frequently detected in a sample of water from a site; 34 percent of the samples had two to five pesticides detected in the same sample, and 4 percent of the samples had six or more pesticides detected. Dieldrin was detected at 20 sites, 9 of which were from either domestic or public supply wells, at a concentration above the Health-Based Screening Level (HBSL) of 0.002 µg/L. Diazinon was detected at a concentration greater than the HBSL of 1 µg/L at a single site, which was also a domestic supply well. These are the only samples where a pesticide exceeded a human-health benchmark.
The most frequently occurring pesticide compounds were four herbicides—atrazine, simazine, metolachlor, and prometon—and deethylatrazine, a degradate of atrazine. These pesticides typically were detected at concentrations that were less than 10 percent of a human-health benchmark. Of the four frequently occurring pesticides, only samples for atrazine (3 percent) and simazine (0.1 percent) had concentrations that exceeded 10 percent of the human-health benchmark; most of these cases were in agricultural areas. It is important to note, however, that the most frequently occurring pesticide degradate compound—deethylatrazine—has no human-health benchmark. Using a common assessment level of 0.01 µg/L, four of the aquifers—Biscayne, Mississippian, Piedmont, and Valley and Ridge—had at least one of these five compounds detected in more than 30 percent of the wells sampled. These four aquifers, along with the Ordovician, Ozark Plateaus, and Prairie du Chien aquifers were the aquifers or aquifer systems that had concentrations of pesticides that exceeded 10 percent of a human-health benchmark. Water recharged after 1953 had a significantly higher percentage of detections of pesticides than water recharged before 1953, and water from unconfined aquifers had a significantly higher percentage of detections of pesticides than water from confined or semiconfined/mixed confined aquifers. Water from sites in unconfined aquifers, where land use was agricultural or urban, accounted for the vast majority of detections of pesticides. Dissolved oxygen concentration was positively related to pesticide occurrence, which likely reflects the positive association between dissolved oxygen concentration and recently recharged water.
Water samples were collected for analysis of VOCs at 793 sites—154 samples were analyzed for 54 VOCs from 1993 through 1995 and 639 samples were analyzed for 86 VOCs from 1996 through 2005. Twenty percent of samples contained one or more VOCs at concentrations greater than or equal to 0.2 µg/L (159 of 793 samples). The aquifers with the highest percentage of samples containing one or more VOCs were the Castle Hayne (about 41 percent of samples) and Biscayne aquifers (34 percent). The most frequently detected VOCs were chloroform, tetrahydrofuran, tetrachloroethene (PCE), toluene, acetone, ethylmethylketone, methyl tert-butyl ether (MTBE), and trichloroethene (TCE). Low-level concentrations of VOCs occurred in a much larger percentage of a subset of the data (the 639 samples analyzed using a low-level analytical method). In these samples, 69 percent of the 639 samples contained 1 or more VOCs, indicating the vulnerability of the carbonate aquifers to low-level VOC contamination. Four VOCs were detected at concentrations exceeding their respective MCLs in five samples, all of which were from drinking-water wells. Vinyl chloride concentrations exceeded the MCL of 2 µg/L in two samples from urban areas in the unconfined Biscayne aquifer. PCE, TCE, and 1,2-dichloropropane each had one sample with a concentration greater than their MCLs of 5 µg/L; these samples were from agricultural and urban areas in the unconfined Mississippian aquifer.
Water quality in the 12 carbonate aquifers was highly variable. Most of the samples met drinking-water standards. The occurrence of anthropogenic contaminants was related to contaminant sources but also was affected by degree of aquifer confinement, ground-water age, and redox status. Areas with higher amounts of agricultural or urban land in unconfined aquifers were the most likely to have elevated concentrations of anthropogenic contaminants.