This assessment of groundwater-quality conditions of the Columbia Plateau, Snake River Plain, and Oahu for the period 1992–2010 is part of the U.S. Geological Survey’s National Water Quality Assessment (NAWQA) program. It shows where, when, why, and how specific water-quality conditions occur in groundwater of the three study areas and yields science-based implications for assessing and managing the quality of these water resources. The primary aquifers in the Columbia Plateau, Snake River Plain, and Oahu are mostly composed of fractured basalt, which makes their hydrology and geochemistry similar. In spite of the hydrogeologic similarities, there are climatic differences that affect the agricultural practices overlying the aquifers, which in turn affect the groundwater quality. Understanding groundwater-quality conditions and the natural and human factors that control groundwater quality is important because of the implications to human health, the sustainability of rural agricultural economies, and the substantial costs associated with land and water management, conservation, and regulation.
\nThe principal regional aquifers of the Columbia Plateau, Snake River Plain, and Oahu are highly vulnerable to contamination by chemicals applied at the land surface; essentially, they are as vulnerable as many shallow surficial aquifers elsewhere. The permeable and largely unconfined character of principal aquifers in the Columbia Plateau, Snake River Plain, and Oahu allow water and chemicals to infiltrate to the water table despite depths to water commonly in the hundreds of feet. The aquifers are essentially unconfined over large areas, having few extensive clay layers to impede infiltration through permeable volcanic rock and alluvial sediments. Agriculture is intensive in all three study areas, and heavy irrigation has imposed large artificial flows of irrigation recharge that rival or exceed natural recharge rates. Fertilizers and pesticides applied at land surface are leached from soil and transported to deep water tables with the infiltrating irrigation recharge, resulting in a layer of degraded water quality overlying better quality regional groundwater beneath. This “irrigation-recharge layer” is best known on Oahu, where it has been studied since the 1960s; however, the extent of nitrate and pesticide contamination in the Columbia Plateau and Snake River Plain indicate that the same situation exists in those areas. Contamination from agricultural and urban activities is present not only at shallow depths in surficial materials of the three areas, but extends regionally in the deep, principal bedrock aquifers that are tapped for drinking water by domestic and public-supply wells.
\nNaturally occurring constituents and nitrate concentrations above human-health benchmarks—Maximum Contaminant Levels (MCLs), and Health-Based Screening Levels (HBSLs)—were more common in the Columbia Plateau and the Snake River Plain than in Oahu. Concentrations of anthropogenic constituents (constituents related to human activities) above human-health benchmarks were more common in Oahu. Naturally occurring contaminants, such as arsenic and radon, may be present in groundwater at concentrations of potential concern for human health in relatively undeveloped settings that otherwise may not be perceived as susceptible to contamination. Even though the median depth to groundwater in Oahu is more than 300 feet, the common occurrence of anthropogenic compounds in groundwater indicates that Oahu has a high susceptibility to contamination.
\nNitrate concentrations in groundwater were above the national background concentrations of 1 milligram per liter (mg/L) in all three study areas. In the Columbia Plateau, nitrate exceeded the human-health benchmark of 10 mg/L in 20 percent of the wells sampled. In the Snake River Plain, nitrate exceeded the human-health benchmark of 10 mg/L in 3 percent of the wells sampled. Nitrate can persist in groundwater for years and even decades in the oxygen-rich groundwater of the Columbia Plateau and the Snake River Plain, so prudent groundwater protection measures are critical to protect drinking water resources by reducing nitrate leaching from the land surface.
\nNitrate logistic regression models indicated that areas with a high percentage of land in crops (such as potatoes or sugarcane) and soils with low amounts of organic matter are most likely to have elevated nitrate concentrations in the groundwater. Areas where agricultural activities were absent had much lower probabilities of detecting elevated nitrate concentrations. The Columbia Plateau had a much higher probability of having elevated nitrate concentrations, with most of the land area having greater than a 50 percent probability of elevated nitrate concentrations. Oahu and the Snake River Plain had a much lower probability of having elevated nitrate concentrations because of their lower percentage of agricultural land.
\nPesticides were detected at many sites in groundwater of the Columbia Plateau, Snake River Plain, and Oahu but generally at low concentrations below human-health benchmarks. Atrazine and its degradate (a compound produced from the breakdown of a parent pesticide), deethylatrazine, were the most commonly detected pesticides in groundwater sampled in the Columbia Plateau and Snake River Plain. Bromacil was the most commonly detected pesticide on Oahu. The other pesticides most commonly detected in the study areas include simazine, hexazinone, metribuzin, diuron, prometon, metolachlor, p,p’-DDE, dieldrin, 2-4-D, and alachlor. DDE (a degradate of DDT) and dieldrin are still being detected in groundwater despite having been banned for more than 30 years. Codetection of multiple pesticides in water from a single well was common. The widespread occurrence of pesticides in groundwater in the study areas indicates that the groundwater is highly susceptible to pesticide contamination.
\nSome pesticides were detected in groundwater samples from all three study areas, but other pesticides were detected only in samples from Oahu, or only in samples from the Columbia Plateau and Snake River Plain. This is because some pesticides (such as atrazine) are broad-spectrum pesticides that are used on many crops in many different areas of the United States. Other pesticides (such as simazine, metribuzin, and metolachlor) are used on row crops (such as potatoes, barley, and alfalfa) grown in the Columbia Plateau and Snake River Plain, but not on pineapple or sugarcane grown in Oahu.
\nAtrazine logistic-regression models indicate that areas with a high percentage of land in crops (such as potatoes or sugarcane), a low percentage of fallow land, and highly permeable soils with low amounts of organic matter are most likely to have atrazine detected in the groundwater. Areas where agricultural activities were absent had much lower probabilities of atrazine being detected. The Snake River Plain had a much higher probability of atrazine detections, with more than 50 percent of the land area having greater than a 50 percent probability of atrazine contamination. Oahu had a much lower probability of atrazine contamination, with only 24 percent of the land area having greater than a 50 percent probability of atrazine contamination.
\nOahu and the Columbia Plateau had some of the highest percentages of soil fumigant detections in groundwater in the United States. Soil fumigants are volatile organic compounds (VOCs) used as pesticides, which are applied to soils to reduce populations of plant parasitic nematodes (harmful rootworms), weeds, fungal pathogens, and other soil-borne microorganisms. They are used in Oahu and the Columbia Plateau on crops such as pineapple and potatoes. All three areas (Columbia Plateau, Snake River Plain, and Oahu) had fumigant concentrations exceeding human-health benchmarks for drinking water.
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The NAWQA Program has published findings in local study-unit reports encompassing parts of the Cambrian-Ordovician aquifer system. Data collected from the aquifer system were used in national synthesis reports on selected topics such as specific water-quality constituent classes, well type, or aquifer material; however, a synthesis of groundwater quality at the principal aquifer scale has not been completed and is therefore the major purpose of this report. Water samples collected by the NAWQA Program were analyzed for various classes of characteristics including physical properties, major ions, trace elements, nutrients and dissolved organic carbon, radionuclides (tritium, radon, and radium), pesticides, and volatile organic compounds. Subsequent sections of this report provide discussions on these classes of characteristics. The assessment objectives of this report are to (1) summarize constituent concentrations and compare them to human-health benchmarks and non-health guidelines; (2) determine the geographic distribution of constituent concentrations and relate them to various factors such as confining conditions, well type, land use, and groundwater age; and (3) evaluate near-decadal-scale changes in nitrate concentrations and pesticide detections. The most recent sample collected from each well by the NAWQA Program was used for most analyses. Near-decadal-scale changes in nitrate concentrations and pesticide detections were evaluated for selected well networks by using the most recent sample from each well and comparing it to the results from a sample collected 7 or 11 years earlier. Because some of the NAWQA well networks provide a limited areal coverage of the aquifer system, data for raw water samples from other USGS sources and state agencies were included to expand the data coverage into areas between the NAWQA well networks and into northeastern Missouri. Many of the maps in this report that show concentrations of selected constituents include data from other sources to expand on the geographic area covered by the NAWQA data.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20115229","collaboration":"National Water-Quality Assessment Program","usgsCitation":"Wilson, J.T., 2012, Water-quality assessment of the Cambrian-Ordovician aquifer system in the northern Midwest, United States: U.S. Geological Survey Scientific Investigations Report 2011-5229, xvi, 129 p.; Appendices; Maps ; PDF Download of Appendix 1; PDF Download of Appendix 3, https://doi.org/10.3133/sir20115229.","productDescription":"xvi, 129 p.; Appendices; Maps ; PDF Download of Appendix 1; PDF Download of Appendix 3","startPage":"i","endPage":"154","numberOfPages":"170","onlineOnly":"N","additionalOnlineFiles":"Y","costCenters":[{"id":346,"text":"Indiana Water Science Center","active":true,"usgs":true}],"links":[{"id":254770,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/sir_2011_5229.gif"},{"id":254764,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/sir/2011/5229/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","otherGeospatial":"Midwest;Cambrian-ordovician Aquifer System","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bcdafe4b08c986b32e0a6","contributors":{"authors":[{"text":"Wilson, John T. 0000-0001-6752-4069 jtwilson@usgs.gov","orcid":"https://orcid.org/0000-0001-6752-4069","contributorId":1954,"corporation":false,"usgs":true,"family":"Wilson","given":"John","email":"jtwilson@usgs.gov","middleInitial":"T.","affiliations":[{"id":346,"text":"Indiana Water Science Center","active":true,"usgs":true},{"id":35860,"text":"Ohio-Kentucky-Indiana Water Science Center","active":true,"usgs":true}],"preferred":false,"id":463968,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70038331,"text":"70038331 - 2012 - An investigation of submarine groundwater—borne nutrient fluxes to the west Florida shelf and recurrent harmful algal blooms","interactions":[],"lastModifiedDate":"2025-05-13T18:16:43.562686","indexId":"70038331","displayToPublicDate":"2012-05-04T09:30:00","publicationYear":"2012","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2620,"text":"Limnology and Oceanography","active":true,"publicationSubtype":{"id":10}},"title":"An investigation of submarine groundwater—borne nutrient fluxes to the west Florida shelf and recurrent harmful algal blooms","docAbstract":"A cross‐shelf, water‐column mass balance of radon‐222 (222Rn) provided estimates of submarine groundwater discharge (SGD), which were then used to quantify benthic nutrient fluxes. Surface water and groundwater were collected along a shore‐normal transect that extended from Tampa Bay, Florida, across the Pinellas County peninsula, to the 10‐m isobath in the Gulf of Mexico. Samples were analyzed for 222Rn and radium‐223,224,226 (223,224,226Ra) activities as well as inorganic and organic nutrients. Cross‐shore gradients of 222Rn and 223,224,226Ra activities indicate a nearshore source for these isotopes, which mixes with water characterized by low activities offshore. Radon‐based SGD rates vary between 2.5 and 15 cm d−1 proximal to the shoreline and decrease offshore. The source of SGD is largely shallow exchange between surface and pore waters, although deeper groundwater cycling may also be important. Enrichment of total dissolved nitrogen and soluble reactive phosphorus in pore water combined with SGD rates results in specific nutrient fluxes comparable to or greater than estuarine fluxes from Tampa Bay. The significance of these fluxes to nearshore blooms of Karenia brevis is highlighted by comparison with prescribed nutrient demands for bloom maintenance and growth. Whereas our flux estimates do not indicate SGD and benthic fluxes as the dominant nutrient source to the harmful algal blooms, SGD‐derived loads do narrow the deficit between documented nutrient supplies and bloom demands.
","language":"English","publisher":"Association for the Sciences of Limnology and Oceanography","doi":"10.4319/lo.2012.57.2.0471","usgsCitation":"Smith, C.G., and Swarzenski, P.W., 2012, An investigation of submarine groundwater—borne nutrient fluxes to the west Florida shelf and recurrent harmful algal blooms: Limnology and Oceanography, v. 57, no. 2, p. 471-485, https://doi.org/10.4319/lo.2012.57.2.0471.","productDescription":"15 p.","startPage":"471","endPage":"485","costCenters":[{"id":574,"text":"St. Petersburg Coastal and Marine Science Center","active":true,"usgs":true}],"links":[{"id":381844,"rank":2,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":474511,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.4319/lo.2012.57.2.0471","text":"Publisher Index Page"}],"country":"United States","state":"Florida","county":"Pinellas","city":"Tampa Bay","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -82.77099609375,\n 27.449790329784214\n ],\n [\n -82.11181640625,\n 27.449790329784214\n ],\n [\n -82.11181640625,\n 28.22697003891834\n ],\n [\n -82.77099609375,\n 28.22697003891834\n ],\n [\n -82.77099609375,\n 27.449790329784214\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"57","issue":"2","noUsgsAuthors":false,"publicationDate":"2012-04-10","publicationStatus":"PW","scienceBaseUri":"5059ea91e4b0c8380cd4894d","contributors":{"authors":[{"text":"Smith, Christopher G. 0000-0002-8075-4763 cgsmith@usgs.gov","orcid":"https://orcid.org/0000-0002-8075-4763","contributorId":3410,"corporation":false,"usgs":true,"family":"Smith","given":"Christopher","email":"cgsmith@usgs.gov","middleInitial":"G.","affiliations":[{"id":574,"text":"St. Petersburg Coastal and Marine Science Center","active":true,"usgs":true},{"id":186,"text":"Coastal and Marine Geology Program","active":true,"usgs":true},{"id":24708,"text":"Lower Mississippi-Gulf Water Science Center","active":true,"usgs":true}],"preferred":true,"id":463902,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Swarzenski, Peter W. 0000-0003-0116-0578 pswarzen@usgs.gov","orcid":"https://orcid.org/0000-0003-0116-0578","contributorId":1070,"corporation":false,"usgs":true,"family":"Swarzenski","given":"Peter","email":"pswarzen@usgs.gov","middleInitial":"W.","affiliations":[{"id":520,"text":"Pacific Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":true,"id":463901,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70038021,"text":"ofr20121045 - 2012 - Groundwater quality in the Upper Susquehanna River Basin, New York, 2009","interactions":[],"lastModifiedDate":"2012-04-30T16:43:35","indexId":"ofr20121045","displayToPublicDate":"2012-04-11T00:00:00","publicationYear":"2012","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":"2012-1045","title":"Groundwater quality in the Upper Susquehanna River Basin, New York, 2009","docAbstract":"Water samples were collected from 16 production wells and 14 private residential wells in the Upper Susquehanna River Basin from August through December 2009 and were analyzed to characterize the groundwater quality in the basin. Wells at 16 of the sites were completed in sand and gravel aquifers, and 14 were finished in bedrock aquifers. In 2004–2005, six of these wells were sampled in the first Upper Susquehanna River Basin study. Water samples from the 2009 study were analyzed for 10 physical properties and 137 constituents that included nutrients, organic carbon, major inorganic ions, trace elements, radionuclides, pesticides, volatile organic compounds, and 4 types of bacterial analyses. Results of the water-quality analyses are presented in tabular form for individual wells, and summary statistics for specific constituents are presented by aquifer type. The results are compared with Federal and New York State drinking-water standards, which typically are identical. The results indicate that groundwater genrally is of acceptable quality, although concentrations of some constituents exceeded at least one drinking-water standard at 28 of the 30 wells. These constituents include: pH, sodium, aluminum, manganese, iron, arsenic, radon-222, residue on evaporation, total and fecal coliform including Escherichia coli and heterotrophic plate count.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/ofr20121045","collaboration":"Prepared in cooperation with New York State Department of Environmental Conservation","usgsCitation":"Reddy, J.E., and Risen, A.J., 2012, Groundwater quality in the Upper Susquehanna River Basin, New York, 2009: U.S. Geological Survey Open-File Report 2012-1045, v, 12 p.; Appendix, https://doi.org/10.3133/ofr20121045.","productDescription":"v, 12 p.; Appendix","startPage":"i","endPage":"30","numberOfPages":"35","onlineOnly":"Y","costCenters":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"links":[{"id":254485,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ofr_2012_1045.gif"},{"id":254480,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/of/2012/1045/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"New York","otherGeospatial":"Susquehanna River Basin","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a2dbbe4b0c8380cd5bfdb","contributors":{"authors":[{"text":"Reddy, James E. 0000-0002-6998-7267 jreddy@usgs.gov","orcid":"https://orcid.org/0000-0002-6998-7267","contributorId":1080,"corporation":false,"usgs":true,"family":"Reddy","given":"James","email":"jreddy@usgs.gov","middleInitial":"E.","affiliations":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"preferred":true,"id":463260,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Risen, Amy J.","contributorId":88070,"corporation":false,"usgs":true,"family":"Risen","given":"Amy","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":463261,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70007180,"text":"ofr20111320 - 2012 - Groundwater quality in the Delaware and St. Lawrence River Basins, New York, 2010","interactions":[],"lastModifiedDate":"2012-03-08T17:16:42","indexId":"ofr20111320","displayToPublicDate":"2012-01-23T10:22:00","publicationYear":"2012","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":"2011-1320","title":"Groundwater quality in the Delaware and St. Lawrence River Basins, New York, 2010","docAbstract":"Water samples were collected from 10 production and domestic wells in the Delaware River Basin in New York and from 20 production and domestic wells in the St. Lawrence River Basin in New York from August through November 2010 to characterize groundwater quality in the basins. The samples were collected and processed by standard U.S. Geological Survey procedures and were analyzed for 147 physiochemical properties and constituents, including major ions, nutrients, trace elements, pesticides, volatile organic compounds (VOCs), radionuclides, and indicator bacteria.
\nThe Delaware River Basin covers 2,360 square miles in New York, and is underlain mainly by shale and sandstone bedrock with other types of bedrock present locally. The bedrock is overlain by till in much of the basin, but surficial deposits of saturated sand and gravel are present in some areas. Five of the wells sampled in the Delaware study area are completed in sand and gravel deposits, and five are completed in bedrock. Groundwater in the Delaware study area was typically neutral or slightly acidic; the water typically was soft. Bicarbonate, chloride, and calcium were the major ions with the greatest median concentrations; the dominant nutrient was nitrate. Strontium, barium, iron, and boron were the trace elements with the highest median concentrations. Radon was detected in all samples with activities greater than 300 picocuries per liter; the greatest radon activities were in samples from bedrock wells. Four pesticides, all herbicides or their degradates, were detected in four samples at trace levels; five VOCs, including four trihalomethanes and tetrachloromethane, were detected in two samples. Coliform bacteria were detected in five samples, but fecal coliform bacteria and Escherichia coli (E. coli) were not detected in any samples from the Delaware study area.
\nThe St. Lawrence River Basin covers 5,650 square miles in New York. The St. Lawrence River Basin in New York is underlain by crystalline, carbonate, and sandstone bedrock. The bedrock is overlain by till or lacustrine and marine deposits in much of the basin. Surficial deposits of saturated sand and gravel are present locally, but most wells in the basin are completed in bedrock. Five of the wells sampled in the St. Lawrence study area are completed in sand and gravel deposits, and 15 are completed in bedrock. Groundwater in the St. Lawrence study area was typically neutral or slightly basic; the water typically was hard. Bicarbonate, sulfate, and calcium were the major ions with the greatest median concentrations; the dominant nutrient was nitrate. Strontium, iron, barium, and boron were the trace elements with the highest median concentrations. Radon was detected in two-thirds of samples with activities greater than 300 picocuries per liter; the greatest radon activities were in samples from bedrock wells. Seven pesticides, including 5 herbicides, an herbicide degradate, and an insecticide, were detected in 11 samples at trace levels; 3 VOCs (tetrachloroethene, toluene, and trichloromethane, or chloroform) were detected in 2 samples. Coliform bacteria were detected in 7 samples, and E. coli were detected in two samples in the St. Lawrence study area.
\nWater quality in both study areas is generally good, but concentrations of some constituents equaled or exceeded current or proposed Federal or New York State drinking-water standards. The standards exceeded are color (one sample in the St. Lawrence study area), pH (three samples in the Delaware study area), sodium (one sample in the St. Lawrence study area), total dissolved solids (one sample in the St. Lawrence study area), aluminum (one sample in the Delaware study area and one sample in the St. Lawrence study area), iron (seven samples in the St. Lawrence study area), manganese (one sample in the Delaware study area and five samples in the St. Lawrence study area), gross alpha radioactivity (one sample in the St. Lawrence study area), radon-222 (10 samples in the Delaware study area and 14 samples in the St. Lawrence study area), and bacteria (5 samples in the Delaware study area and 10 samples in the St. Lawrence study area). E. coli bacteria were detected in samples from two wells in the St. Lawrence study area. Concentrations of chloride, fluoride, sulfate, nitrate, nitrite, antimony, arsenic, barium, beryllium, cadmium, chromium, copper, lead, mercury, selenium, silver, thallium, zinc, and uranium did not exceed existing drinking-water standards in any of the samples collected.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/ofr20111320","collaboration":"Prepared in cooperation with the New York State Department of Environmental Conservation","usgsCitation":"Nystrom, E.A., 2012, Groundwater quality in the Delaware and St. Lawrence River Basins, New York, 2010: U.S. Geological Survey Open-File Report 2011-1320, vii, 24 p.; Appendices, https://doi.org/10.3133/ofr20111320.","productDescription":"vii, 24 p.; Appendices","onlineOnly":"Y","costCenters":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"links":[{"id":116369,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ofr_2011_1320.gif"},{"id":115678,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/of/2011/1320/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"New York","otherGeospatial":"Delaware River Basin;St. Lawrence River Basin","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -75.66666666666667,41.25 ], [ -75.66666666666667,42.5 ], [ -74.25,42.5 ], [ -74.25,41.25 ], [ -75.66666666666667,41.25 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a2db1e4b0c8380cd5bfb9","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":356023,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70042820,"text":"70042820 - 2012 - Physical setting and natural sources of exposure to carcinogenic trace elements and radionuclides in Lahontan Valley, Nevada","interactions":[],"lastModifiedDate":"2013-03-12T16:00:08","indexId":"70042820","displayToPublicDate":"2012-01-01T00:00:00","publicationYear":"2012","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1219,"text":"Chemico-Biological Interactions","active":true,"publicationSubtype":{"id":10}},"title":"Physical setting and natural sources of exposure to carcinogenic trace elements and radionuclides in Lahontan Valley, Nevada","docAbstract":"In Lahontan Valley, Nevada, arsenic, cobalt, tungsten, uranium, radon, and polonium-210 are carcinogens that occur naturally in sediments and groundwater. Arsenic and cobalt are principally derived from erosion of volcanic rocks in the local mountains and tungsten and uranium are derived from erosion of granitic rocks in headwater reaches of the Carson River. Radon and 210Po originate from radioactive decay of uranium in the sediments. Arsenic, aluminum, cobalt, iron, and manganese concentrations in household dust suggest it is derived from the local soils. Excess zinc and chromium in the dust are probably derived from the vacuum cleaner used to collect the dust, or household sources such as the furnace. Some samples have more than 5 times more cobalt in the dust than in the local soil, but whether the source of the excess cobalt is anthropogenic or natural cannot be determined with the available data. Cobalt concentrations are low in groundwater, but arsenic, uranium, radon, and 210Po concentrations often exceed human-health standards, and sometime greatly exceed them. Exposure to radon and its decay products in drinking water can vary significantly depending on when during the day that the water is consumed. Although the data suggests there have been no long term changes in groundwater chemistry that corresponds to the Lahontan Valley leukemia cluster, the occurrence of the very unusual leukemia cluster in an area with numerous 210Po and arsenic contaminated wells is striking, particularly in conjunction with the exceptionally high levels of urinary tungsten in Lahontan Valley residents. Additional research is needed on potential exposure pathways involving food or inhalation, and on synergistic effects of mixtures of these natural contaminants on susceptibility to development of leukemia.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Chemico-Biological Interactions","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/j.cbi.2011.04.004","usgsCitation":"Seiler, R.L., 2012, Physical setting and natural sources of exposure to carcinogenic trace elements and radionuclides in Lahontan Valley, Nevada: Chemico-Biological Interactions, v. 196, no. 3, p. 79-86, https://doi.org/10.1016/j.cbi.2011.04.004.","productDescription":"8 p.","startPage":"79","endPage":"86","numberOfPages":"8","additionalOnlineFiles":"N","ipdsId":"IP-023222","costCenters":[{"id":465,"text":"Nevada Water Science Center","active":true,"usgs":true}],"links":[{"id":269184,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":269183,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.cbi.2011.04.004"}],"country":"United States","state":"Nevada","otherGeospatial":"Lahontan Valley","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -119.127414,39.463302 ], [ -119.127414,39.766719 ], [ -118.724621,39.766719 ], [ -118.724621,39.463302 ], [ -119.127414,39.463302 ] ] ] } } ] }","volume":"196","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"51404e8ae4b089809dbf44b9","contributors":{"authors":[{"text":"Seiler, Ralph L.","contributorId":13609,"corporation":false,"usgs":true,"family":"Seiler","given":"Ralph","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":472326,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70197908,"text":"70197908 - 2012 - Chemical mixtures in untreated water from public-supply wells in the U.S. — Occurrence, composition, and potential toxicity","interactions":[],"lastModifiedDate":"2018-06-26T11:41:06","indexId":"70197908","displayToPublicDate":"2012-01-01T00:00:00","publicationYear":"2012","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3352,"text":"Science of the Total Environment","active":true,"publicationSubtype":{"id":10}},"title":"Chemical mixtures in untreated water from public-supply wells in the U.S. — Occurrence, composition, and potential toxicity","docAbstract":"Chemical mixtures are prevalent in groundwater used for public water supply, but little is known about their potential health effects. As part of a large-scale ambient groundwater study, we evaluated chemical mixtures across multiple chemical classes, and included more chemical contaminants than in previous studies of mixtures in public-supply wells. We (1) assessed the occurrence of chemical mixtures in untreated source-water samples from public-supply wells, (2) determined the composition of the most frequently occurring mixtures, and (3) characterized the potential toxicity of mixtures using a new screening approach. The U.S. Geological Survey collected one untreated water sample from each of 383 public wells distributed across 35 states, and analyzed the samples for as many as 91 chemical contaminants. Concentrations of mixture components were compared to individual human-health benchmarks; the potential toxicity of mixtures was characterized by addition of benchmark-normalized component concentrations. Most samples (84%) contained mixtures of two or more contaminants, each at concentrations greater than one-tenth of individual benchmarks. The chemical mixtures that most frequently occurred and had the greatest potential toxicity primarily were composed of trace elements (including arsenic, strontium, or uranium), radon, or nitrate. Herbicides, disinfection by-products, and solvents were the most common organic contaminants in mixtures. The sum of benchmark-normalized concentrations was greater than 1 for 58% of samples, suggesting that there could be potential for mixtures toxicity in more than half of the public-well samples. Our findings can be used to help set priorities for groundwater monitoring and suggest future research directions for drinking-water treatment studies and for toxicity assessments of chemical mixtures in water resources.
","language":"English","publisher":"Elsevier","doi":"10.1016/j.scitotenv.2012.05.044","usgsCitation":"Toccalino, P.L., Norman, J.E., and Scott, J.C., 2012, Chemical mixtures in untreated water from public-supply wells in the U.S. — Occurrence, composition, and potential toxicity: Science of the Total Environment, v. 431, p. 262-270, https://doi.org/10.1016/j.scitotenv.2012.05.044.","productDescription":"9 p.","startPage":"262","endPage":"270","ipdsId":"IP-030178","costCenters":[],"links":[{"id":355349,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","volume":"431","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5b46f6ece4b060350a15d3be","contributors":{"authors":[{"text":"Toccalino, Patricia L. 0000-0003-1066-1702 ptocca@usgs.gov","orcid":"https://orcid.org/0000-0003-1066-1702","contributorId":933,"corporation":false,"usgs":true,"family":"Toccalino","given":"Patricia","email":"ptocca@usgs.gov","middleInitial":"L.","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":false,"id":739023,"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":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true},{"id":518,"text":"Oregon Water Science Center","active":true,"usgs":true},{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":739024,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Scott, Jonathon C. jcscott@usgs.gov","contributorId":5449,"corporation":false,"usgs":true,"family":"Scott","given":"Jonathon","email":"jcscott@usgs.gov","middleInitial":"C.","affiliations":[],"preferred":true,"id":739025,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70005677,"text":"ofr20101094 - 2011 - Continuous resistivity profiling data from the Corsica River Estuary, Maryland","interactions":[],"lastModifiedDate":"2018-05-02T21:29:11","indexId":"ofr20101094","displayToPublicDate":"2011-10-04T00:00:00","publicationYear":"2011","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":"2010-1094","title":"Continuous resistivity profiling data from the Corsica River Estuary, Maryland","docAbstract":"Submarine groundwater discharge (SGD) into Maryland's Corsica River Estuary was investigated as part of a larger study to determine its importance in nutrient delivery to the Chesapeake Bay. The Corsica River Estuary represents a coastal lowland setting typical of much of the eastern bay. An interdisciplinary U.S. Geological Survey (USGS) science team conducted field operations in the lower estuary in April and May 2007. Resource managers are concerned about nutrients that are entering the estuary via SGD that may be contributing to eutrophication, harmful algal blooms, and fish kills. Techniques employed in the study included continuous resistivity profiling (CRP), piezometer sampling of submarine groundwater, and collection of a time series of radon tracer activity in surface water. A CRP system measures electrical resistivity of saturated subestuarine sediments to distinguish those bearing fresh water (high resistivity) from those with saline or brackish pore water (low resistivity). This report describes the collection and processing of CRP data and summarizes the results. Based on a grid of 67.6 kilometers of CRP data, low-salinity (high-resistivity) groundwater extended approximately 50-400 meters offshore from estuary shorelines at depths of 5 to >12 meters below the sediment surface, likely beneath a confining unit. A band of low-resistivity sediment detected along the axis of the estuary indicated the presence of a filled paleochannel containing brackish groundwater. The meandering paleochannel likely incised through the confining unit during periods of lower sea level, allowing the low-salinity groundwater plumes originating from land to mix with brackish subestuarine groundwater along the channel margins and to discharge. A better understanding of the spatial variability and geological controls of submarine groundwater flow beneath the Corsica River Estuary could lead to improved models and mitigation strategies for nutrient over-enrichment in the estuary and in other similar settings.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/ofr20101094","usgsCitation":"Cross, V., Bratton, J., Worley, C., Crusius, J., and Kroeger, K., 2011, Continuous resistivity profiling data from the Corsica River Estuary, Maryland: U.S. Geological Survey Open-File Report 2010-1094, HTML Document; DVD-ROM, https://doi.org/10.3133/ofr20101094.","productDescription":"HTML Document; DVD-ROM","temporalStart":"2007-04-01","temporalEnd":"2007-05-31","costCenters":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"links":[{"id":116026,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ofr_2010_1094.gif"},{"id":94293,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/of/2010/1094/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"Maryl","otherGeospatial":"Corsica River Estuary","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -76.15083333333334,39.05 ], [ -76.15083333333334,39.1 ], [ -76.1,39.1 ], [ -76.1,39.05 ], [ -76.15083333333334,39.05 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4afde4b07f02db696aac","contributors":{"authors":[{"text":"Cross, V.A.","contributorId":88687,"corporation":false,"usgs":true,"family":"Cross","given":"V.A.","email":"","affiliations":[],"preferred":false,"id":353055,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bratton, J.F.","contributorId":94354,"corporation":false,"usgs":true,"family":"Bratton","given":"J.F.","email":"","affiliations":[],"preferred":false,"id":353056,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Worley, C.R.","contributorId":43479,"corporation":false,"usgs":true,"family":"Worley","given":"C.R.","email":"","affiliations":[],"preferred":false,"id":353054,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Crusius, John 0000-0003-2554-0831 jcrusius@usgs.gov","orcid":"https://orcid.org/0000-0003-2554-0831","contributorId":2155,"corporation":false,"usgs":true,"family":"Crusius","given":"John","email":"jcrusius@usgs.gov","affiliations":[{"id":114,"text":"Alaska Science Center","active":true,"usgs":true},{"id":119,"text":"Alaska Science Center Geology Minerals","active":true,"usgs":true}],"preferred":true,"id":353053,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Kroeger, K.D.","contributorId":26060,"corporation":false,"usgs":true,"family":"Kroeger","given":"K.D.","email":"","affiliations":[],"preferred":false,"id":353052,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70005456,"text":"ds609 - 2011 - Groundwater-quality data in the northern Coast Ranges study unit, 2009: Results from the California GAMA Program","interactions":[],"lastModifiedDate":"2012-03-08T17:16:40","indexId":"ds609","displayToPublicDate":"2011-09-20T00:00:00","publicationYear":"2011","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":"609","title":"Groundwater-quality data in the northern Coast Ranges study unit, 2009: Results from the California GAMA Program","docAbstract":"Groundwater quality in the 633-square-mile Northern Coast Ranges (NOCO) study unit was investigated by the U.S. Geological Survey (USGS) from June to November 2009, as part of the California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and Assessment (GAMA) Program's Priority Basin Project (PBP) and the U.S. Geological Survey National Water-Quality Assessment Program (NAWQA). The GAMA-PBP was developed in response to the California Groundwater Quality Monitoring Act of 2001 and is being conducted in collaboration with the SWRCB and Lawrence Livermore National Laboratory (LLNL). The NOCO study unit was the thirtieth study unit to be sampled as part of the GAMA-PBP.\nThe GAMA Northern Coast Ranges study was designed to provide a spatially unbiased assessment of untreated-groundwater quality in the primary aquifer systems, and to facilitate statistically consistent comparisons of untreated groundwater quality throughout California. The primary aquifer systems (hereinafter referred to as primary aquifers) are defined as that part of the aquifer corresponding to the perforation intervals of wells listed in the California Department of Public Health (CDPH) database for the NOCO study unit. The quality of groundwater in shallow or deep water-bearing zones may differ from the quality of groundwater in the primary aquifers; shallow groundwater may be more vulnerable to surficial contamination.\nIn the NOCO study unit, groundwater samples were collected from 58 wells in 2 study areas (Interior Basins and Coastal Basins) in Napa, Lake, Mendocino, Glenn, Humboldt, and Del Norte Counties. The 58 wells were selected by using a spatially distributed, randomized grid-based method to provide statistical representation of the study areas. GAMA-PBP wells sampled as part of the spatially-distributed, randomized grid-cell network are referred to as \"grid wells.\"The groundwater samples were analyzed for organic and special-interest constituents (volatile organic compounds [VOC], pesticides and pesticide degradates, and perchlorate), naturally occurring inorganic constituents (trace elements, nutrients, dissolved organic carbon [DOC], major and minor ions, silica, total dissolved solids [TDS], and alkalinity), radioactive constituents (radon-222, radium isotopes, gross alpha and gross beta radioactivity, lead-210, and polonium-210), and microbial indicators (F-specific and somatic coliphage, Escherichia coli [E. coli] and total coliform). Naturally occurring isotopes (stable isotopes of hydrogen and oxygen in water, stable isotopes of carbon in dissolved inorganic carbon, activities of tritium, and carbon-14 abundance), and dissolved noble gases also were measured to identify the sources and ages of the sampled groundwater. In total, 239 constituents and 12 field water-quality indicators were measured.\nThree types of quality-control samples (blanks, replicates, and matrix-spikes) were collected at up to 12 percent of the wells in the NOCO study unit, and the results for these samples were used to evaluate the quality of the data for the groundwater samples. Blanks rarely contained detectable concentrations of any constituent, suggesting that contamination from sample collection procedures was not a significant source of bias in the data for the groundwater samples. Replicate samples generally were within the limits of acceptable analytical reproducibility. Matrix-spike recoveries were within the acceptable range (70 to 130 percent) for approximately 89 percent of the compounds.\nThis study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, untreated groundwater typically is treated, disinfected, and (or) blended with other waters to maintain water quality. Regulatory benchmarks apply to water that is served to the consumer, not to untreated groundwater. However, to provide some context for the results, concentrations of constituents measured in the untreated groundwa","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/ds609","collaboration":"A product of the California Groundwater Ambient Monitoring and Assessment (GAMA) Program Prepared in cooperation with the California State Water Resources Control Board and the U.S. Geological Survey National Water-Quality Assessment Program","usgsCitation":"Mathany, T., Dawson, B.J., Shelton, J.L., and Belitz, K., 2011, Groundwater-quality data in the northern Coast Ranges study unit, 2009: Results from the California GAMA Program: U.S. Geological Survey Data Series 609, x, 65 p.; Appendix, https://doi.org/10.3133/ds609.","productDescription":"x, 65 p.; Appendix","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":116320,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ds_609.jpg"},{"id":94152,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/ds/609/","linkFileType":{"id":5,"text":"html"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4afbe4b07f02db69621c","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":352554,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Dawson, Barbara J. 0000-0002-0209-8158 bjdawson@usgs.gov","orcid":"https://orcid.org/0000-0002-0209-8158","contributorId":1102,"corporation":false,"usgs":true,"family":"Dawson","given":"Barbara","email":"bjdawson@usgs.gov","middleInitial":"J.","affiliations":[],"preferred":true,"id":352552,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Shelton, Jennifer L. 0000-0001-8508-0270 jshelton@usgs.gov","orcid":"https://orcid.org/0000-0001-8508-0270","contributorId":1155,"corporation":false,"usgs":true,"family":"Shelton","given":"Jennifer","email":"jshelton@usgs.gov","middleInitial":"L.","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":352553,"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":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":352551,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70005297,"text":"sir20115059 - 2011 - Trace elements and radon in groundwater across the United States, 1992-2003","interactions":[],"lastModifiedDate":"2012-03-08T17:16:40","indexId":"sir20115059","displayToPublicDate":"2011-08-30T00:00:00","publicationYear":"2011","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":"2011-5059","title":"Trace elements and radon in groundwater across the United States, 1992-2003","docAbstract":"Trace-element concentrations in groundwater were evaluated for samples collected between 1992 and 2003 from aquifers across the United States as part of the U.S. Geological Survey National Water-Quality Assessment Program. This study describes the first comprehensive analysis of those data by assessing occurrence (concentrations above analytical reporting levels) and by comparing concentrations to human-health benchmarks (HHBs). Data from 5,183 monitoring and drinking-water wells representing more than 40 principal and other aquifers in humid and dry regions and in various land-use settings were used in the analysis. Trace elements measured include aluminum (Al), antimony (Sb), arsenic (As), barium (Ba), beryllium (Be), boron (B), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb), lithium (Li), manganese (Mn), molybdenum (Mo), nickel (Ni), selenium (Se), silver (Ag), strontium (Sr), thallium (Tl), uranium (U), vanadium (V), and zinc (Zn). Radon (Rn) gas also was measured and is included in the data analysis. Climate influenced the occurrence and distribution of trace elements in groundwater whereby more trace elements occurred and were found at greater concentrations in wells in drier regions of the United States than in humid regions. In particular, the concentrations of As, Ba, B, Cr, Cu, Mo, Ni, Se, Sr, U, V, and Zn were greater in the drier regions, where processes such as chemical evolution, ion complexation, evaporative concentration, and redox (oxidation-reduction) controls act to varying degrees to mobilize these elements. Al, Co, Fe, Pb, and Mn concentrations in groundwater were greater in humid regions of the United States than in dry regions, partly in response to lower groundwater pH and (or) more frequent anoxic conditions. In groundwater from humid regions, concentrations of Cu, Pb, Rn, and Zn were significantly greater in drinking-water wells than in monitoring wells. Samples from drinking-water wells in dry regions had greater concentrations of As, Ba, Pb, Li, Sr, V, and Zn, than samples from monitoring wells. In humid regions, however, concentrations of most trace elements were greater in monitoring wells than in drinking-water wells; the exceptions were Cu, Pb, Zn, and Rn. Cu, Pb, and Zn are common trace elements in pumps and pipes used in the construction of drinking-water wells, and contamination from these sources may have contributed to their concentrations. Al, Sb, Ba, B, Cr, Co, Fe, Mn, Mo, Ni, Se, Sr, and U concentrations were all greater in monitoring wells than in drinking-water wells in humid regions. Groundwater from wells in agricultural settings had greater concentrations of As, Mo, and U than groundwater from wells in urban settings, possibly owing to greater pH in the agricultural wells. Significantly greater concentrations of B, Cr, Se, Ag, Sr, and V also were found in agricultural wells in dry regions. Groundwater from dry-region urban wells had greater concentrations of Co, Fe, Pb, Li, Mn, and specific conductance than groundwater from agricultural wells. The geologic composition of aquifers and aquifer geochemistry are among the major factors affecting trace-element occurrence. Trace-element concentrations in groundwater were characterized in aquifers from eight major groups based on geologic material, including (1) unconsolidated sand and gravel; (2) glacial unconsolidated sand and gravel; (3) semiconsolidated sand; (4) sandstone; (5) sandstone and carbonate rock; (6) carbonate rock; (7) basaltic and other volcanic rock; and (8) crystalline rock. The majority of groundwater samples and the largest percentages of exceedences of HHBs were in the glacial and nonglacial unconsolidated sand and gravel aquifers; in these aquifers, As, Mn, and U are the most common trace elements exceeding HHBs. Overall, 19 percent of wells (962 of 5,097) exceeded an HHB for at least one trace element. The trace elements with HHBs included in this summary were Sb, As, Ba, Be, B, Cd, Cr, ","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20115059","usgsCitation":"Ayotte, J., Gronberg, J., and Apodaca, L.E., 2011, Trace elements and radon in groundwater across the United States, 1992-2003: U.S. Geological Survey Scientific Investigations Report 2011-5059, xi, 77 p.; Appendices, https://doi.org/10.3133/sir20115059.","productDescription":"xi, 77 p.; Appendices","startPage":"i","endPage":"115","numberOfPages":"126","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":468,"text":"New Hampshire-Vermont Water Science Center","active":false,"usgs":true}],"links":[{"id":126234,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/sir_2011_5059.gif"},{"id":91872,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/sir/2011/5059/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -175,7 ], [ -175,74 ], [ -65,74 ], [ -65,7 ], [ -175,7 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a4ee4b07f02db627e10","contributors":{"authors":[{"text":"Ayotte, Joseph D. jayotte@usgs.gov","contributorId":1802,"corporation":false,"usgs":true,"family":"Ayotte","given":"Joseph D.","email":"jayotte@usgs.gov","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"preferred":false,"id":352238,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Gronberg, Jo Ann M.","contributorId":18342,"corporation":false,"usgs":true,"family":"Gronberg","given":"Jo Ann M.","affiliations":[],"preferred":false,"id":352240,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Apodaca, Lori E. lapodaca@usgs.gov","contributorId":1844,"corporation":false,"usgs":true,"family":"Apodaca","given":"Lori","email":"lapodaca@usgs.gov","middleInitial":"E.","affiliations":[{"id":432,"text":"National Minerals Information Center","active":true,"usgs":true}],"preferred":true,"id":352239,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70005189,"text":"ofr20111180 - 2011 - Groundwater quality in the Lake Champlain Basin, New York, 2009","interactions":[],"lastModifiedDate":"2012-03-08T17:16:41","indexId":"ofr20111180","displayToPublicDate":"2011-08-15T00:00:00","publicationYear":"2011","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":"2011-1180","title":"Groundwater quality in the Lake Champlain Basin, New York, 2009","docAbstract":"Water was sampled from 20 production and domestic wells from August through November 2009 to characterize groundwater quality in the Lake Champlain Basin in New York. Of the 20 wells sampled, 8 were completed in sand and gravel, and 12 were completed in bedrock. The samples were collected and processed by standard U.S. Geological Survey procedures and were analyzed for 147 physiochemical properties and constituents, including major ions, nutrients, trace elements, pesticides, volatile organic compounds (VOCs), radionuclides, and indicator bacteria.\n\n Water quality in the study area is generally good, but concentrations of some constituents equaled or exceeded current or proposed Federal or New York State drinking-water standards; these were color (1 sample), pH (3 samples), sodium (3 samples), total dissolved solids (4 samples), iron (4 samples), manganese (3 samples), gross alpha radioactivity (1 sample), radon-222 (10 samples), and bacteria (5 samples). The pH of all samples was typically neutral or slightly basic (median 7.1); the median water temperature was 9.7°C. The ions with the highest median concentrations were bicarbonate [median 158 milligrams per liter (mg/L)] and calcium (median 45.5 mg/L). Groundwater in the study area is soft to very hard, but more samples were hard or very hard (121 mg/L or more as CaCO3) than were moderately hard or soft (120 mg/L or less as CaCO3); the median hardness was 180 mg/L as CaCO3. The maximum concentration of nitrate plus nitrite was 3.79 mg/L as nitrogen, which did not exceed established drinking-water standards for nitrate plus nitrite (10 mg/L as nitrogen). The trace elements with the highest median concentrations were strontium (median 202 micrograms per liter [μg/L]), and iron (median 55 μg/L in unfiltered water). Six pesticides and pesticide degradates, including atrazine, fipronil, disulfoton, prometon, and two pesticide degradates, CIAT and desulfinylfipronil, were detected among five samples at concentrations of 0.02 μg/L or less; they included herbicides, herbicide degradates, insecticides, and insecticide degradates. Six VOCs were detected among six samples; these included a solvent, the gasoline additive methyl tert-butyl ether (MTBE), and four trihalomethanes. The highest radon-222 activities were in samples from crystalline bedrock wells (maximum 4,100 picocuries per liter [pCi/L]); half of all samples exceeded a proposed U.S. Environmental Protection Agency (USEPA) drinking-water standard of 300 pCi/L. Total coliform bacteria were detected in five samples, fecal coliform bacteria were detected in one sample, and Escherichia coli (E. coli) were not detected in any sample.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/ofr20111180","collaboration":"Prepared in cooperation with the New York State Department of Environmental Conservation","usgsCitation":"Nystrom, E.A., 2011, Groundwater quality in the Lake Champlain Basin, New York, 2009: U.S. Geological Survey Open-File Report 2011-1180, vi, 21 p.; Appendices, https://doi.org/10.3133/ofr20111180.","productDescription":"vi, 21 p.; Appendices","onlineOnly":"N","costCenters":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"links":[{"id":116873,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ofr_2011_1180.JPG"},{"id":24577,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/of/2011/1180/","linkFileType":{"id":5,"text":"html"}}],"scale":"100000","projection":"Universal Transverse Mercator","country":"United States","state":"New York","county":"Clinton;Essex;Franklin;Warren;Washington","otherGeospatial":"Lake Champlain Basin","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -74.5,43 ], [ -74.5,45 ], [ -73,45 ], [ -73,43 ], [ -74.5,43 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a95e4b07f02db659f5a","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":352054,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70005167,"text":"sir20115115 - 2011 - Factors affecting groundwater quality in the Valley and Ridge aquifers, eastern United States, 1993-2002","interactions":[],"lastModifiedDate":"2012-03-08T17:16:41","indexId":"sir20115115","displayToPublicDate":"2011-08-11T00:00:00","publicationYear":"2011","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":"2011-5115","title":"Factors affecting groundwater quality in the Valley and Ridge aquifers, eastern United States, 1993-2002","docAbstract":"Chemical and microbiological analyses of water from 230 wells and 35 springs in the Valley and Ridge Physiographic Province, sampled between 1993 and 2002, indicated that bedrock type (carbonate or siliciclastic rock) and land use were dominant factors influencing groundwater quality across a region extending from northwestern Georgia to New Jersey. The analyses included naturally occurring compounds (major mineral ions and radon) and anthropogenic contaminants [pesticides and volatile organic compounds (VOCs)], and contaminants, such as nitrate and bacteria, which commonly increase as a result of human activities. Natural factors, such as topographic position and the mineral composition of underlying geology, act to produce basic physical and geochemical conditions in groundwater that are reflected in physical properties, such as pH, temperature, specific conductance, and alkalinity, and in chemical concentrations of dissolved oxygen, radon, and major mineral ions. Anthropogenic contaminants were most commonly found in water from wells and springs in carbonate-rock aquifers. Nitrate concentrations exceeded U.S. Environmental Protection Agency maximum contaminant levels in 12 percent of samples, most of which were from carbonate-rock aquifers. Escherichia coli (E. coli), pesticide, and VOC detection frequencies were significantly higher in samples from sites in carbonate-rock aquifers. Naturally occurring elements, such as radon, iron, and manganese, were found in higher concentrations in siliciclastic-rock aquifers. Radon levels exceeded the proposed maximum contaminant level of 300 picocuries per liter in 74 percent of the samples, which were evenly distributed between carbonate- and siliciclastic-rock aquifers. The land use in areas surrounding wells and springs was another significant explanatory variable for the occurrence of anthropogenic compounds. Nitrate and pesticide concentrations were highest in samples collected from sites in agricultural areas and lowest in samples collected from sites in undeveloped areas. Volatile organic compounds were detected most frequently and in highest concentrations in samples from sites in urban areas, and least frequently in agricultural and undeveloped areas. No volatile organic compound concentrations and concentrations from only one pesticide, dieldrin, exceeded human-health benchmarks.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20115115","collaboration":"National Water-Quality Assessment Program","usgsCitation":"Johnson, G.C., Zimmerman, T.M., Lindsey, B., and Gross, E.L., 2011, Factors affecting groundwater quality in the Valley and Ridge aquifers, eastern United States, 1993-2002: U.S. Geological Survey Scientific Investigations Report 2011-5115, xii, 70 p., https://doi.org/10.3133/sir20115115.","productDescription":"xii, 70 p.","temporalStart":"1992-10-01","temporalEnd":"2002-09-30","costCenters":[{"id":532,"text":"Pennsylvania Water Science Center","active":true,"usgs":true}],"links":[{"id":116142,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/sir_2011_5115.jpg"},{"id":24570,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/sir/2011/5115/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"Alabama;Georgia;Tennessee;North Carolina;Virginia;Kentucky;West Virginia;Pennsylvania;Maryl;New Jersey;New York","otherGeospatial":"Valley And Ridge Aquifers;Delaware River Basin;Susquehanna River Basin;Potomac River Basin;Tennessee River Basin","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -90,32 ], [ -90,42 ], [ -73.5,42 ], [ -73.5,32 ], [ -90,32 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a05e4b07f02db5f8819","contributors":{"authors":[{"text":"Johnson, Gregory C. 0000-0003-3683-5010 gcjohnso@usgs.gov","orcid":"https://orcid.org/0000-0003-3683-5010","contributorId":1420,"corporation":false,"usgs":true,"family":"Johnson","given":"Gregory","email":"gcjohnso@usgs.gov","middleInitial":"C.","affiliations":[{"id":581,"text":"Tennessee Water Science Center","active":true,"usgs":true},{"id":24708,"text":"Lower Mississippi-Gulf Water Science Center","active":true,"usgs":true}],"preferred":true,"id":352034,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Zimmerman, Tammy M. 0000-0003-0842-6981 tmzimmer@usgs.gov","orcid":"https://orcid.org/0000-0003-0842-6981","contributorId":2359,"corporation":false,"usgs":true,"family":"Zimmerman","given":"Tammy","email":"tmzimmer@usgs.gov","middleInitial":"M.","affiliations":[{"id":532,"text":"Pennsylvania Water Science Center","active":true,"usgs":true}],"preferred":false,"id":352035,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lindsey, Bruce D. 0000-0002-7180-4319 blindsey@usgs.gov","orcid":"https://orcid.org/0000-0002-7180-4319","contributorId":434,"corporation":false,"usgs":true,"family":"Lindsey","given":"Bruce D.","email":"blindsey@usgs.gov","affiliations":[{"id":532,"text":"Pennsylvania Water Science Center","active":true,"usgs":true}],"preferred":false,"id":352033,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Gross, Eliza L. 0000-0002-8835-3382 egross@usgs.gov","orcid":"https://orcid.org/0000-0002-8835-3382","contributorId":430,"corporation":false,"usgs":true,"family":"Gross","given":"Eliza","email":"egross@usgs.gov","middleInitial":"L.","affiliations":[{"id":532,"text":"Pennsylvania Water Science Center","active":true,"usgs":true}],"preferred":true,"id":352032,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70004636,"text":"ds598 - 2011 - Groundwater quality of the Gulf Coast aquifer system, Houston, Texas, 2010","interactions":[],"lastModifiedDate":"2016-08-11T15:30:40","indexId":"ds598","displayToPublicDate":"2011-06-15T13:50:03","publicationYear":"2011","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":"598","title":"Groundwater quality of the Gulf Coast aquifer system, Houston, Texas, 2010","docAbstract":"During March–December 2010, the U.S. Geological Survey, in cooperation with the city of Houston, collected source-water samples from 60 municipal supply wells in the Houston area. These data were collected as part of an ongoing study to determine concentrations, spatial extent, and associated geochemical conditions that might be conducive for mobility and transport of selected naturally occurring contaminants (selected trace elements and radionuclides) in the Gulf Coast aquifer system in the Houston area. In the summers of 2007 and 2008, a reconnaissance-level survey of these constituents in untreated water from 28 municipal supply wells was completed in the Houston area. Included in this report are the complete analytical results for 47 of the 60 samples collected in 2010—those results which were received from the laboratories and reviewed by the authors as of December 31, 2010. All of the wells sampled were screened in the Gulf Coast aquifer system; 22 were screened entirely in the Evangeline aquifer, and the remaining 25 wells contained screened intervals that intersected both Evangeline and Chicot aquifers. The data documented in this report were collected as part of an ongoing study to characterize source-water-quality conditions in untreated groundwater prior to drinking-water treatment. An evaluation of contaminant occurrence in source water provides background information regarding the presence of a contaminant in the environment. Because source-water samples were collected prior to any treatment or blending that potentially could alter contaminant concentrations, the water-quality results documented by this report represent the quality of the source water, not the quality of finished drinking water provided to the public.
\nSamples were analyzed for major ions (calcium, magnesium, potassium, sodium, bromide, chloride, fluoride, silica, and sulfate), residue on evaporation (dissolved solids), trace elements (arsenic, barium, boron, chromium, iron, lithium, manganese, molybdenum, selenium, strontium, and vanadium), and selected radionuclides (gross alpha- and beta-particle activity [at 72 hours and 30 days], carbon-14, radium-226, radon-222, and uranium). Field measurements were made of selected physicochemical (relating to both physical and chemical) properties (oxidation-reduction potential, turbidity, dissolved-oxygen concentration, pH, specific conductance, water temperature, and alkalinity) and unfiltered sulfides.
\nSimilar to the results from the reconnaissance survey, physicochemical properties, major ions, and trace elements varied considerably. The ranges of selected physicochemical properties were as follows: oxidation-reduction potential ranged from -173 to 466 millivolts, dissolved oxygen ranged from less than 0.1 to 4.4 milligrams per liter, pH ranged from 7.2 to 7.8, specific conductance ranged from 439 to 724 microsiemens per centimeter at 25 degrees Celsius, and alkalinity ranged from 159 to 276 milligrams per liter as calcium carbonate. The largest ranges in concentration for filtered major ion constituents were obtained for cations sodium and calcium and for anions chloride and sulfate. Arsenic concentrations measured in samples from the 47 wells ranged from 1.6 to 23.5 micrograms per liter. The maximum concentration of arsenic (23.5 micrograms per liter) was measured in the source-water sample from well LJ-65-12-328.
\nQuantifiable concentrations of barium, boron, lithium, molybdenum, and strontium were measured in all 47 filtered, source-water samples. Quantifiable concentrations of manganese were measured in 46 source-water samples, and an estimated concentration of manganese was measured in 1 sample. Chromium, iron, selenium, and vanadium were detected in 24 or more of the 47 source-water samples.
\nGross alpha-particle activities and beta-particle activities for all 47 samples were analyzed at 72 hours after sample collection and again at 30 days after sample collection, allowing for the measurement of the activity of short-lived isotopes. Gross alpha-particle activities reported in this report were not adjusted for activity contributions by radon or uranium and, therefore, are conservatively high estimates if compared to the U.S. Environmental Protection Agency National Primary Drinking Water Regulation for adjusted gross alpha-particle activity. The gross alpha-particle activities at 30 days in the samples ranged from R0.60 to 25.5 picocuries per liter and at 72 hours ranged from 2.58 to 39.7 picocuries per liter, and the \"R\" preceding the value of 0.60 picocuries per liter refers to a nondetected result less than the sample-specific critical level. Gross beta-particle activities measured at 30 days ranged from 1.17 to 14.4 picocuries per liter and at 72 hours ranged from 1.97 to 4.4 picocuries per liter. Filtered uranium was detected in quantifiable amounts in all of the 47 wells sampled. The uranium concentrations ranged from 0.03 to 42.7 micrograms per liter. One sample was analyzed for carbon-14, and the amount of modern atmospheric carbon was reported as 0.2 percent. Six source-water samples collected from municipal supply wells were analyzed for radium-226, and all of the concentrations were considered detectable concentrations (greater than their associated sample-specific critical level). Three source-water samples collected were analyzed for radon-222, and all of the concentrations were substantially greater than the associated sample-specific critical level.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/ds598","usgsCitation":"Oden, J.H., Brown, D.W., and Oden, T., 2011, Groundwater quality of the Gulf Coast aquifer system, Houston, Texas, 2010: U.S. Geological Survey Data Series 598, iv, 18 p.; Tables, https://doi.org/10.3133/ds598.","productDescription":"iv, 18 p.; Tables","startPage":"i","endPage":"64","numberOfPages":"68","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":583,"text":"Texas Water Science Center","active":true,"usgs":true}],"links":[{"id":116134,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ds_598.gif"},{"id":21880,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/ds/598/","linkFileType":{"id":5,"text":"html"}}],"scale":"2000000","projection":"Universal Transverse Mercator projection","datum":"North American Datum of 1983","country":"United States","state":"Texas","city":"Houston","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -95.66666666666667,29.583333333333332 ], [ -95.66666666666667,30.133333333333333 ], [ -95.16666666666667,30.133333333333333 ], [ -95.16666666666667,29.583333333333332 ], [ -95.66666666666667,29.583333333333332 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a94e4b07f02db658f88","contributors":{"authors":[{"text":"Oden, Jeannette H. 0000-0002-6473-1553 jhoden@usgs.gov","orcid":"https://orcid.org/0000-0002-6473-1553","contributorId":1152,"corporation":false,"usgs":true,"family":"Oden","given":"Jeannette","email":"jhoden@usgs.gov","middleInitial":"H.","affiliations":[{"id":583,"text":"Texas Water Science Center","active":true,"usgs":true}],"preferred":true,"id":350910,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Brown, Dexter W. dwbrown@usgs.gov","contributorId":3062,"corporation":false,"usgs":true,"family":"Brown","given":"Dexter","email":"dwbrown@usgs.gov","middleInitial":"W.","affiliations":[],"preferred":true,"id":350912,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Oden, Timothy D. toden@usgs.gov","contributorId":1284,"corporation":false,"usgs":true,"family":"Oden","given":"Timothy D.","email":"toden@usgs.gov","affiliations":[],"preferred":true,"id":350911,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70004584,"text":"ofr20111112 - 2011 - Groundwater quality in the Chemung River Basin, New York, 2008","interactions":[],"lastModifiedDate":"2012-03-08T17:16:40","indexId":"ofr20111112","displayToPublicDate":"2011-06-07T16:50:09","publicationYear":"2011","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":"2011-1112","title":"Groundwater quality in the Chemung River Basin, New York, 2008","docAbstract":"The second groundwater quality study of the Chemung River Basin in south-central New York was conducted as part of the U.S. Geological Survey 305(b) water-quality-monitoring program. Water samples were collected from five production wells and five private residential wells from October through December 2008. The samples were analyzed to characterize the chemical quality of the groundwater. Five of the wells are screened in sand and gravel aquifers, and five are finished in bedrock aquifers. Two of these wells were also sampled for the first Chemung River Basin study of 2003. Samples were analyzed for 6 physical properties and 217 constituents, including nutrients, major inorganic ions, trace elements, radionuclides, pesticides, volatile organic compounds, phenolic compounds, organic carbon, and four types of bacterial analyses. Results of the water-quality analyses for individual wells are presented in tables, and summary statistics for specific constituents are presented by aquifer type. The results are compared with Federal and New York State drinking-water standards, which typically are identical.\n\nWater quality in the study area is generally good, but concentrations of some constituents equaled or exceeded current or proposed Federal or New York State drinking-water standards; these were: sodium (one sample), total dissolved solids (one sample), aluminum (one sample), iron (one sample), manganese (four samples), radon-222 (eight samples), trichloroethene (one sample), and bacteria (four samples). The pH of all samples was typically neutral or slightly basic (median 7.5); the median water temperature was 11.0 degrees Celsius (?C). The ions with the highest median concentrations were bicarbonate (median 202 milligrams per liter [mg/L]) and calcium (median 59.0 mg/L). Groundwater in the study area is moderately hard to very hard, but more samples were hard or very hard (121 mg/L as calcium carbonate (CaCO3) or greater) than were moderately hard (61-120 mg/L as CaCO3); the median hardness was 205 mg/L as CaCO3. The maximum concentration of nitrate plus nitrite was 3.67 mg/L as nitrogen, which did not exceed established drinking-water standards for nitrate plus nitrite (10 mg/L as nitrogen). The trace elements with the highest median concentrations were strontium (median 196.5 micrograms per liter [(u or mu)g/L]), barium (median 186 (u or mu)g/L), and iron (median 72.5 (u or mu)g/L in unfiltered water). Five pesticides and pesticide degradates were detected among four samples at concentrations of 0.11 (u or mu)g/L or less; they included herbicides and herbicide degradates. Six volatile organic compounds (VOCs) were detected among four samples; these included four solvents, methyl tert-butyl ether, and one trihalomethane. Trichloroethene, a solvent, was detected in one production well at 5.5 (u or mu)g/L; the Federal and New York State Maximum Contaminant Level (MCL) (5 (u or mu)g/L) was exceeded. The highest radon-222 activities were in samples from bedrock wells [maximum 1,740 picocuries per liter (pCi/L)]; eight of the wells sampled exceeded a proposed U.S. Environmental Protection Agency (USEPA) drinking-water standard of 300 pCi/L. Any detection of coliform bacteria indicates a potential violation of New York State health regulations; total coliform bacteria were detected in four samples, and fecal coliform bacteria were detected in one sample.μμμ","doi":"10.3133/ofr20111112","usgsCitation":"Risen, A.J., and Reddy, J.E., 2011, Groundwater quality in the Chemung River Basin, New York, 2008: U.S. Geological Survey Open-File Report 2011-1112, iv, 10 p.; Appendix, https://doi.org/10.3133/ofr20111112.","productDescription":"iv, 10 p.; Appendix","additionalOnlineFiles":"N","costCenters":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"links":[{"id":116201,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ofr_2011_1112.gif"},{"id":21856,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/of/2011/1112/","linkFileType":{"id":5,"text":"html"}}],"projection":"Universal Transverse Mercator projection","state":"New York","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -78,42 ], [ -78,42.75 ], [ -76.5,42.75 ], [ -76.5,42 ], [ -78,42 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a95e4b07f02db65976a","contributors":{"authors":[{"text":"Risen, Amy J.","contributorId":88070,"corporation":false,"usgs":true,"family":"Risen","given":"Amy","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":350802,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Reddy, James E. 0000-0002-6998-7267 jreddy@usgs.gov","orcid":"https://orcid.org/0000-0002-6998-7267","contributorId":1080,"corporation":false,"usgs":true,"family":"Reddy","given":"James","email":"jreddy@usgs.gov","middleInitial":"E.","affiliations":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"preferred":true,"id":350801,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":99176,"text":"ofr20111074 - 2011 - Groundwater quality in the Eastern Lake Ontario Basin, New York, 2008","interactions":[],"lastModifiedDate":"2021-11-03T18:18:39.31246","indexId":"ofr20111074","displayToPublicDate":"2011-04-01T00:00:00","publicationYear":"2011","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":"2011-1074","title":"Groundwater quality in the Eastern Lake Ontario Basin, New York, 2008","docAbstract":"Water samples were collected from nine production wells and nine private residential wells in the Eastern Lake Ontario Basin of New York from August through October 2008 and analyzed to characterize the chemical quality of groundwater. The wells were selected to provide adequate spatial coverage of the 3,225-square-mile study area; areas of greatest groundwater use were emphasized. Eight of the 18 wells sampled, were screened in sand and gravel aquifers, and 10 were finished in bedrock aquifers. The samples were collected and processed by standard U.S. Geological Survey procedures and were analyzed for 223 physical properties and constituents, including major ions, nutrients, trace elements, radon-222, pesticides, volatile organic compounds (VOCs), and indicator bacteria.\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 (2 samples), pH (1 sample), sodium (5 samples), chloride (1 sample), aluminum (2 samples), iron (5 unfiltered samples), manganese (3 samples), radon-222 (13 samples), and bacteria (4 samples). Dissolved-oxygen concentrations in samples from wells finished in sand and gravel [median 3.8 milligrams per liter (mg/L)] were greater than those from wells finished in bedrock (median less than 0.7 mg/L). The pH of all samples was typically neutral or slightly basic (median 7.4); the median water temperature was 11.3 degrees Celsius. The ions with the highest concentrations were bicarbonate (median 174 mg/L) and calcium (median 24.1 mg/L). Groundwater in the basin ranges from soft to moderately hard [less than or equal to 120 mg/L as CaCO3] and median hardness was 90 mg/L as CaCO3. Concentrations of nitrate plus nitrite in samples from sand and gravel wells (median concentration 0.42 mg/L as nitrogen) were generally higher than those in samples from bedrock wells (median <0.04 mg/L as nitrogen). The trace elements with the highest concentrations were strontium [median 138 micrograms per liter (mug/L)], barium (median 38.2 mug/L) and iron (median 44 mug/L). Radon-222 activities were generally high [median 500 picocuries per liter (pCi/L)]; 72 percent of all samples exceeded a proposed U.S. Environmental Protection Agency (USEPA) drinking-water standard of 300 pCi/L. Five pesticides and pesticide degradates were detected among 6 samples at concentrations of 0.03 mug/L or less; most were herbicides or their degradates. Six VOCs were detected among 9 samples at concentrations of 1.2 mug/L or less; these included 3 trihalomethanes, benzene, toluene, and xylenes. Total coliform bacteria were detected in 3 samples, and the heterotrophic plate count exceeded the USEPA maximum contaminant level (MCL) of 500 colony forming units in one sample. Fecal coliform bacteria, including Escherichia coli, were not detected in any sample.","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ofr20111074","usgsCitation":"Risen, A.J., and Reddy, J.E., 2011, Groundwater quality in the Eastern Lake Ontario Basin, New York, 2008: U.S. Geological Survey Open-File Report 2011-1074, v, 32 p., https://doi.org/10.3133/ofr20111074.","productDescription":"v, 32 p.","onlineOnly":"N","additionalOnlineFiles":"N","temporalStart":"2008-08-01","temporalEnd":"2008-10-31","costCenters":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"links":[{"id":116276,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ofr_2011_1074.gif"},{"id":391331,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_95115.htm"},{"id":14589,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/of/2011/1074/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"New York","otherGeospatial":"eastern Lake Ontario basin","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -76.5,43.25 ], [ -76.5,44.5 ], [ -74.5,44.5 ], [ -74.5,43.25 ], [ -76.5,43.25 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a95e4b07f02db659982","contributors":{"authors":[{"text":"Risen, Amy J.","contributorId":88070,"corporation":false,"usgs":true,"family":"Risen","given":"Amy","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":307672,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Reddy, James E. 0000-0002-6998-7267 jreddy@usgs.gov","orcid":"https://orcid.org/0000-0002-6998-7267","contributorId":1080,"corporation":false,"usgs":true,"family":"Reddy","given":"James","email":"jreddy@usgs.gov","middleInitial":"E.","affiliations":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"preferred":true,"id":307671,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70032514,"text":"70032514 - 2011 - Pseudospectral modeling and dispersion analysis of Rayleigh waves in viscoelastic media","interactions":[],"lastModifiedDate":"2012-03-12T17:21:21","indexId":"70032514","displayToPublicDate":"2011-01-01T00:00:00","publicationYear":"2011","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3418,"text":"Soil Dynamics and Earthquake Engineering","active":true,"publicationSubtype":{"id":10}},"title":"Pseudospectral modeling and dispersion analysis of Rayleigh waves in viscoelastic media","docAbstract":"Multichannel Analysis of Surface Waves (MASW) is one of the most widely used techniques in environmental and engineering geophysics to determine shear-wave velocities and dynamic properties, which is based on the elastic layered system theory. Wave propagation in the Earth, however, has been recognized as viscoelastic and the propagation of Rayleigh waves presents substantial differences in viscoelastic media as compared with elastic media. Therefore, it is necessary to carry out numerical simulation and dispersion analysis of Rayleigh waves in viscoelastic media to better understand Rayleigh-wave behaviors in the real world. We apply a pseudospectral method to the calculation of the spatial derivatives using a Chebyshev difference operator in the vertical direction and a Fourier difference operator in the horizontal direction based on the velocity-stress elastodynamic equations and relations of linear viscoelastic solids. This approach stretches the spatial discrete grid to have a minimum grid size near the free surface so that high accuracy and resolution are achieved at the free surface, which allows an effective incorporation of the free surface boundary conditions since the Chebyshev method is nonperiodic. We first use an elastic homogeneous half-space model to demonstrate the accuracy of the pseudospectral method comparing with the analytical solution, and verify the correctness of the numerical modeling results for a viscoelastic half-space comparing the phase velocities of Rayleigh wave between the theoretical values and the dispersive image generated by high-resolution linear Radon transform. We then simulate three types of two-layer models to analyze dispersive-energy characteristics for near-surface applications. Results demonstrate that the phase velocity of Rayleigh waves in viscoelastic media is relatively higher than in elastic media and the fundamental mode increases by 10-16% when the frequency is above 10. Hz due to the velocity dispersion of P and S waves. ?? 2011 Elsevier Ltd.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Soil Dynamics and Earthquake Engineering","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/j.soildyn.2011.05.004","issn":"02677261","usgsCitation":"Zhang, K., Luo, Y., Xia, J., and Chen, C., 2011, Pseudospectral modeling and dispersion analysis of Rayleigh waves in viscoelastic media: Soil Dynamics and Earthquake Engineering, v. 31, no. 10, p. 1332-1337, https://doi.org/10.1016/j.soildyn.2011.05.004.","startPage":"1332","endPage":"1337","numberOfPages":"6","costCenters":[],"links":[{"id":213723,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.soildyn.2011.05.004"},{"id":241378,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"31","issue":"10","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a8fc5e4b0c8380cd7f961","contributors":{"authors":[{"text":"Zhang, K.","contributorId":71724,"corporation":false,"usgs":true,"family":"Zhang","given":"K.","email":"","affiliations":[],"preferred":false,"id":436574,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Luo, Y.","contributorId":28417,"corporation":false,"usgs":true,"family":"Luo","given":"Y.","email":"","affiliations":[],"preferred":false,"id":436572,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Xia, J.","contributorId":63513,"corporation":false,"usgs":true,"family":"Xia","given":"J.","email":"","affiliations":[],"preferred":false,"id":436573,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Chen, C.","contributorId":98490,"corporation":false,"usgs":true,"family":"Chen","given":"C.","email":"","affiliations":[],"preferred":false,"id":436575,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70035806,"text":"70035806 - 2011 - 210Po in Nevada groundwater and its relation to gross alpha radioactivity","interactions":[],"lastModifiedDate":"2013-02-26T12:18:18","indexId":"70035806","displayToPublicDate":"2011-01-01T00:00:00","publicationYear":"2011","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1861,"text":"Ground Water","active":true,"publicationSubtype":{"id":10}},"title":"210Po in Nevada groundwater and its relation to gross alpha radioactivity","docAbstract":"Polonium-210 (210Po) is a highly toxic alpha emitter that is rarely found in groundwater at activities exceeding 1 pCi/L. 210Po activities in 63 domestic and public-supply wells in Lahontan Valley in Churchill County in northern Nevada, United States, ranged from 0.01 ± 0.005 to 178 ± 16 pCi/L with a median activity of 2.88 pCi/L. Wells with high 210Po activities had low dissolved oxygen concentrations (less than 0.1 mg/L) and commonly had pH greater than 9. Lead-210 activities are low and aqueous 210Po is unsupported by 210Pb, indicating that the 210Po is mobilized from aquifer sediments. The only significant contributors to alpha particle activity in Lahontan Valley groundwater are 234/238U, 222Rn, and 210Po. Radon-222 activities were below 1000 pCi/L and were uncorrelated with 210Po activity. The only applicable drinking water standard for 210Po in the United States is the adjusted gross alpha radioactivity (GAR) standard of 15 pCi/L. 210Po was not volatile in a Nevada well, but volatile 210Po has been reported in a Florida well. Additional information on the volatility of 210Po is needed because GAR is an inappropriate method to screen for volatile radionuclides. About 25% of the samples had 210Po activities that exceed the level associated with a lifetime total cancer risk of 1× 10−4 (1.1 pCi/L) without exceeding the GAR standard. In cases where the 72-h GAR exceeds the uranium activity by more than 5 to 10 pCi/L, an analysis to rule out the presence of 210Po may be justified to protect human health even though the maximum contaminant level for adjusted GAR is not exceeded.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Ground Water","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Wiley","publisherLocation":"Hoboken, NJ","doi":"10.1111/j.1745-6584.2010.00688.x","issn":"0017467X","usgsCitation":"Seiler, R.L., 2011, 210Po in Nevada groundwater and its relation to gross alpha radioactivity: Ground Water, v. 49, no. 2, p. 160-171, https://doi.org/10.1111/j.1745-6584.2010.00688.x.","productDescription":"12 p.","startPage":"160","endPage":"171","costCenters":[{"id":465,"text":"Nevada Water Science Center","active":true,"usgs":true}],"links":[{"id":216353,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1111/j.1745-6584.2010.00688.x"},{"id":244217,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Nevada","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -120.0,35.0 ], [ -120.0,42.0 ], [ -114.0,42.0 ], [ -114.0,35.0 ], [ -120.0,35.0 ] ] ] } } ] }","volume":"49","issue":"2","noUsgsAuthors":false,"publicationDate":"2011-02-22","publicationStatus":"PW","scienceBaseUri":"5059e252e4b0c8380cd45aae","contributors":{"authors":[{"text":"Seiler, R. L.","contributorId":87546,"corporation":false,"usgs":true,"family":"Seiler","given":"R.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":452514,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70036073,"text":"70036073 - 2011 - Evaluation of groundwater discharge into small lakes based on the temporal distribution of radon-222","interactions":[],"lastModifiedDate":"2021-02-03T22:01:42.739416","indexId":"70036073","displayToPublicDate":"2011-01-01T00:00:00","publicationYear":"2011","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2620,"text":"Limnology and Oceanography","active":true,"publicationSubtype":{"id":10}},"title":"Evaluation of groundwater discharge into small lakes based on the temporal distribution of radon-222","docAbstract":"In order to evaluate groundwater discharge into small lakes we constructed a model that is based on the budget of 222Rn (radon, t1/2=3.8 d) as a tracer. The main assumptions in our model are that the lake's waters are well‐mixed horizontally and vertically; the only significant 222Rn source is via groundwater discharge; and the only losses are due to decay and atmospheric evasion. In order to evaluate the groundwater‐derived 222Rn flux, we monitored the 222Rn concentration in lake water over periods long enough (usually 1–3 d) to observe changes likely caused by variations in atmospheric exchange (primarily a function of wind speed and temperature). We then attempt to reproduce the observed record by accounting for decay and atmospheric losses and by estimating the total 222Rn input flux using an iterative approach. Our methodology was tested in two lakes in central Florida: one of which is thought to have significant groundwater inputs (Lake Haines) and another that is known not to have any groundwater inflows but requires daily groundwater augmentation from a deep aquifer (Round Lake). Model results were consistent with independent seepage meter data at both Lake Haines (positive seepage of ∼ 1.6 × 104 m3 d−1 in Mar 2008) and at Round Lake (no net groundwater seepage)
","language":"English","publisher":"Association for the Sciences of Limnology and Oceanography","doi":"10.4319/lo.2011.56.2.0486","issn":"00243590","usgsCitation":"Dimova, N.T., and Burnett, W.C., 2011, Evaluation of groundwater discharge into small lakes based on the temporal distribution of radon-222: Limnology and Oceanography, v. 56, no. 2, p. 486-494, https://doi.org/10.4319/lo.2011.56.2.0486.","productDescription":"9 p.","startPage":"486","endPage":"494","costCenters":[],"links":[{"id":475100,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.4319/lo.2011.56.2.0486","text":"Publisher Index Page"},{"id":246327,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"56","issue":"2","noUsgsAuthors":false,"publicationDate":"2011-02-03","publicationStatus":"PW","scienceBaseUri":"505a0c85e4b0c8380cd52ba4","contributors":{"authors":[{"text":"Dimova, N. T.","contributorId":30080,"corporation":false,"usgs":true,"family":"Dimova","given":"N.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":454028,"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":454029,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70034199,"text":"70034199 - 2011 - Radionuclides, trace elements, and radium residence in phosphogypsum of Jordan","interactions":[],"lastModifiedDate":"2012-03-12T17:21:44","indexId":"70034199","displayToPublicDate":"2011-01-01T00:00:00","publicationYear":"2011","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1538,"text":"Environmental Geochemistry and Health","active":true,"publicationSubtype":{"id":10}},"title":"Radionuclides, trace elements, and radium residence in phosphogypsum of Jordan","docAbstract":"Voluminous stockpiles of phosphogypsum (PG) generated during the wet process production of phosphoric acid are stored at many sites around the world and pose problems for their safe storage, disposal, or utilization. A major concern is the elevated concentration of long-lived 226Ra (half-life = 1,600 years) inherited from the processed phosphate rock. Knowledge of the abundance and mode-of-occurrence of radium (Ra) in PG is critical for accurate prediction of Ra leachability and radon (Rn) emanation, and for prediction of radiation-exposure pathways to workers and to the public. The mean (??SD) of 226Ra concentrations in ten samples of Jordan PG is 601 ?? 98 Bq/kg, which falls near the midrange of values reported for PG samples collected worldwide. Jordan PG generally shows no analytically significant enrichment (< 10%) of 226Ra in the finer (< 53 ??m) grain size fraction. Phosphogypsum samples collected from two industrial sites with different sources of phosphate rock feedstock show consistent differences in concentration of 226Ra and rare earth elements, and also consistent trends of enrichment in these elements with increasing age of PG. Water-insoluble residues from Jordan PG constitute <10% of PG mass but contain 30-65% of the 226Ra. 226Ra correlates closely with Ba in the water-insoluble residues. Uniformly tiny (< 10 ??m) grains of barite (barium sulfate) observed with scanning electron microscopy have crystal morphologies that indicate their formation during the wet process. Barite is a well-documented and efficient scavenger of Ra from solution and is also very insoluble in water and mineral acids. Radium-bearing barite in PG influences the environmental mobility of radium and the radiation-exposure pathways near PG stockpiles. ?? 2010 US Government.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Environmental Geochemistry and Health","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/s10653-010-9328-4","issn":"02694042","usgsCitation":"Zielinski, R.A., Al-Hwaiti, M.S., Budahn, J., and Ranville, J., 2011, Radionuclides, trace elements, and radium residence in phosphogypsum of Jordan: Environmental Geochemistry and Health, v. 33, no. 2, p. 149-165, https://doi.org/10.1007/s10653-010-9328-4.","startPage":"149","endPage":"165","numberOfPages":"17","costCenters":[],"links":[{"id":216877,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s10653-010-9328-4"},{"id":244775,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"33","issue":"2","noUsgsAuthors":false,"publicationDate":"2010-07-11","publicationStatus":"PW","scienceBaseUri":"505a9423e4b0c8380cd81221","contributors":{"authors":[{"text":"Zielinski, R. A. 0000-0002-4047-5129","orcid":"https://orcid.org/0000-0002-4047-5129","contributorId":106930,"corporation":false,"usgs":true,"family":"Zielinski","given":"R.","email":"","middleInitial":"A.","affiliations":[{"id":164,"text":"Central Energy Resources Science Center","active":true,"usgs":true}],"preferred":false,"id":444570,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Al-Hwaiti, M. S.","contributorId":38392,"corporation":false,"usgs":true,"family":"Al-Hwaiti","given":"M.","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":444567,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Budahn, J. R. 0000-0001-9794-8882","orcid":"https://orcid.org/0000-0001-9794-8882","contributorId":83914,"corporation":false,"usgs":true,"family":"Budahn","given":"J. R.","affiliations":[],"preferred":false,"id":444569,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Ranville, J. F.","contributorId":54245,"corporation":false,"usgs":true,"family":"Ranville","given":"J. F.","affiliations":[],"preferred":false,"id":444568,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70157933,"text":"70157933 - 2011 - Natural radium and radon tracers to quantify water exchange and movement in reservoirs","interactions":[],"lastModifiedDate":"2025-05-13T18:18:35.832062","indexId":"70157933","displayToPublicDate":"2011-01-01T00:00:00","publicationYear":"2011","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"Natural radium and radon tracers to quantify water exchange and movement in reservoirs","docAbstract":"Radon and radium isotopes are routinely used to quantify exchange rates between different hydrologic reservoirs. Since their recognition as oceanic tracers in the 1960s, both radon and radium have been used to examine processes such as air-sea exchange, deep oceanic mixing, benthic inputs, and many others. Recently, the application of radon-222 and the radium-quartet (223,224,226,228Ra) as coastal tracers has seen a revelation with the growing interest in coastal groundwater dynamics. The enrichment of these isotopes in benthic fluids including groundwater makes both radium and radon ideal tracers of coastal benthic processes (e.g. submarine groundwater discharge). In this chapter we review traditional and recent advances in the application of radon and radium isotopes to understand mixing and exchange between various hydrologic reservoirs, specifically: (1) atmosphere and ocean, (2) deep and shallow oceanic water masses, (3) coastal groundwater/benthic pore waters and surface ocean, and (4) aquifer-lakes. While the isotopes themselves and their distribution in the environment provide qualitative information about the exchange processes, it is mixing/exchange and transport models for these isotopes that provide specific quantitative information about these processes. Brief introductions of these models and mixing parameters are provided for both historical and more recent studies.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Handbook of environmental isotope geochemistry","largerWorkSubtype":{"id":15,"text":"Monograph"},"language":"English","publisher":"Springer","publisherLocation":"Heidelberg [Germany]; New York","usgsCitation":"Smith, C.G., 2011, Natural radium and radon tracers to quantify water exchange and movement in reservoirs, chap. of Handbook of environmental isotope geochemistry, p. 345-365.","productDescription":"21 p.","startPage":"345","endPage":"365","onlineOnly":"N","additionalOnlineFiles":"N","ipdsId":"IP-025686","costCenters":[{"id":574,"text":"St. Petersburg Coastal and Marine Science Center","active":true,"usgs":true}],"links":[{"id":308915,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"560bb6d9e4b058f706e53da3","contributors":{"editors":[{"text":"Baskaran, Mark","contributorId":87867,"corporation":false,"usgs":false,"family":"Baskaran","given":"Mark","email":"","affiliations":[{"id":7147,"text":"Wayne State University","active":true,"usgs":false}],"preferred":false,"id":574473,"contributorType":{"id":2,"text":"Editors"},"rank":1}],"authors":[{"text":"Smith, Christopher G. 0000-0002-8075-4763 cgsmith@usgs.gov","orcid":"https://orcid.org/0000-0002-8075-4763","contributorId":3410,"corporation":false,"usgs":true,"family":"Smith","given":"Christopher","email":"cgsmith@usgs.gov","middleInitial":"G.","affiliations":[{"id":24708,"text":"Lower Mississippi-Gulf Water Science Center","active":true,"usgs":true},{"id":574,"text":"St. Petersburg Coastal and Marine Science Center","active":true,"usgs":true},{"id":186,"text":"Coastal and Marine Geology Program","active":true,"usgs":true}],"preferred":true,"id":574472,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70006089,"text":"sir20105206 - 2010 - Occurrence and distribution of organic chemicals and nutrients and comparison of water-quality data from public drinking-water supplies in the Columbia aquifer in Delaware, 2000-08","interactions":[],"lastModifiedDate":"2023-03-10T12:40:21.808021","indexId":"sir20105206","displayToPublicDate":"2011-11-29T00:00:00","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":"2010-5206","title":"Occurrence and distribution of organic chemicals and nutrients and comparison of water-quality data from public drinking-water supplies in the Columbia aquifer in Delaware, 2000-08","docAbstract":"The U.S. Geological Survey, in cooperation with the Delaware Department of Natural Resources and Environmental Control and the Delaware Geological Survey, conducted a groundwater-quality investigation to (a) describe the occurrence and distribution of selected contaminants, and (b) document any changes in groundwater quality in the Columbia aquifer public water-supply wells in the Coastal Plain in Delaware between 2000 and 2008. Thirty public water-supply wells located throughout the Columbia aquifer of the Delaware Coastal Plain were sampled from August through November of 2008. Twenty-two of the wells in the sampling network for this project were previously sampled in 2000. Eight new wells were selected to replace wells no longer in use. Groundwater collected from the wells was analyzed for the occurrence and distribution of selected pesticides, pesticide degradates, volatile organic compounds, nutrients, and major inorganic ions. Nine of the wells were analyzed for radioactive elements (radium-226, radium-228, and radon). Groundwater-quality data were compared for sites sampled in both 2000 and 2008 to document any changes in water quality. One or more pesticides were detected in samples from 29 of the 30 wells. There were no significant differences in pesticide and pesticide degradate concentrations and similar compounds were detected when comparing sampling results from 2000 and 2008. Pesticide and pesticide degradate concentrations were generally less than 1 microgram per liter. Twenty-four compounds, 14 pesticides, and 10 pesticide degradates were detected in at least one sample; the pesticide degradates, metolachlor ethanesulfonic acid, deethylatrazine, and alachlor ethanesulfonic acid were the most frequently detected compounds, each found in more than 50 percent of samples. Almost 80 percent of the detected pesticides were agricultural herbicides, which reflects the prevalence and wide distribution of agriculture in sampled areas, as well the dominance of agricultural pesticides among the target analytes for this study. No concentration of a pesticide or pesticide degradate exceeded any regulatory standard. Dieldrin, an insecticide that has been banned for several decades, was detected at a concentration that exceeded a non-regulatory health-based screening level of 0.002 micrograms per liter at nine sites. Volatile organic compounds (VOCs) were generally detected at concentrations of less than 1 microgram per liter, although 7 of the 31 detected VOCs had concentrations greater than 1 microgram per liter. There were no significant differences in VOC concentrations from 2000 to 2008; however, among the resampled wells, the mean number of VOCs detected per well was significantly different over the 8-year period. The number of VOCs detected per well decreased in 73 percent of the resampled wells; the decrease ranged from one to eight fewer detections in 2008 than in 2000. Chloroform and methyl tert-butyl ether were the most frequently detected VOCs, at 90 percent and 63 percent, respectively, among the 30 wells. Solvents were the most frequently detected class of VOCs. All measured concentrations of VOCs in groundwater were below established standards for drinking water and below other health-based guidelines. There were no significant differences in nutrient or major-ion concentrations between 2000 and 2008, however, the medians of two field measurements, pH and dissolved oxygen, were significantly higher in 2008 than in 2000 in the resampled wells. Although pH and dissolved oxygen were higher, water was still acidic and predominantly oxic. Nitrate was the predominant nutrient species in the Columbia aquifer, with a 90-percent detection frequency. The median nitrate concentration in groundwater was 4.88 milligrams per liter, which was slightly lower than, but not significantly different from, the median of 5.23 milligrams per liter for the 2000 samples. Concentrations of nitrate exceeded the U.S. Environmental Protection Agency's Maximum Contaminant Level or Federal drinking-water standard of 10 milligrams per liter as nitrogen in samples from two wells. Eight of the 30 wells sampled had iron or manganese concentrations that exceeded the U.S. Environmental Protection Agency's Secondary Maximum Contaminant Level; nine samples exceeded the Health Advisory Limit set by the Delaware Division of Public Health of 20 milligrams per liter for sodium in drinking water. Two radiochemical isotopes, radium-226 and radon-222, were detected in all nine groundwater samples analyzed; five samples had detectable levels of radium-228 activity. None of the samples exceeded the U.S Environmental Protection Agency's Maximum Contaminant Level for radium or radon in drinking water. Although radioactive elements were more frequently detected in 2008 than in 2000, this increased detection frequency is more likely due to lower detection levels in 2008 than 2000. The average age of groundwater entering the screens of the production wells sampled in 2008 ranged from 6 to 35 years, with a median groundwater age of 22 years. Groundwater age was positively correlated with well depth and negatively correlated with dissolved oxygen. Data from the 22 resampled wells indicate a significant positive difference in the average modeled groundwater-sample-age results. The average groundwater age from samples collected in 2008 was generally 7 years older than the average groundwater age from samples collected in 2000.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/sir20105206","collaboration":"Prepared in cooperation with the Delaware Department of Natural Resources and Environmental Control and the Delaware Geological Survey","usgsCitation":"Reyes, B., 2010, Occurrence and distribution of organic chemicals and nutrients and comparison of water-quality data from public drinking-water supplies in the Columbia aquifer in Delaware, 2000-08: U.S. Geological Survey Scientific Investigations Report 2010-5206, Report: vii, 37 p.; Appendices, https://doi.org/10.3133/sir20105206.","productDescription":"Report: vii, 37 p.; Appendices","costCenters":[{"id":41514,"text":"Maryland-Delaware-District of Columbia Water Science Center","active":true,"usgs":true}],"links":[{"id":116710,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/sir_2010_5206.gif"},{"id":110946,"rank":2,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/sir/2010/5206/","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"Delaware","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -76,38.46666666666667 ], [ -76,40 ], [ -74.83333333333333,40 ], [ -74.83333333333333,38.46666666666667 ], [ -76,38.46666666666667 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4799e4b07f02db48faba","contributors":{"authors":[{"text":"Reyes, Betzaida 0000-0002-1398-0824 breyes@usgs.gov","orcid":"https://orcid.org/0000-0002-1398-0824","contributorId":2250,"corporation":false,"usgs":true,"family":"Reyes","given":"Betzaida","email":"breyes@usgs.gov","affiliations":[{"id":374,"text":"Maryland Water Science Center","active":true,"usgs":true}],"preferred":true,"id":353812,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":98961,"text":"ds548 - 2010 - Groundwater quality of the Gulf Coast aquifer system, Houston, Texas, 2007-08","interactions":[],"lastModifiedDate":"2016-08-11T16:15:08","indexId":"ds548","displayToPublicDate":"2010-12-18T00:00:00","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":"548","title":"Groundwater quality of the Gulf Coast aquifer system, Houston, Texas, 2007-08","docAbstract":"In the summers of 2007 and 2008, the U.S. Geological Survey (USGS), in cooperation with the City of Houston, Texas, completed an initial reconnaissance-level survey of naturally occurring contaminants (arsenic, other selected trace elements, and radionuclides) in water from municipal supply wells in the Houston area. The purpose of this reconnaissance-level survey was to characterize source-water quality prior to drinking water treatment. Water-quality samples were collected from 28 municipal supply wells in the Houston area completed in the Evangeline aquifer, Chicot aquifer, or both. This initial survey is part of ongoing research to determine concentrations, spatial extent, and associated geochemical conditions that might be conducive for mobility and transport of these constituents in the Gulf Coast aquifer system in the Houston area. Samples were analyzed for major ions (calcium, magnesium, potassium, sodium, bromide, chloride, fluoride, silica, and sulfate), selected chemically related properties (residue on evaporation [dissolved solids] and chemical oxygen demand), dissolved organic carbon, arsenic species (arsenate [As(V)], arsenite [As(III)], dimethylarsinate [DMA], and monomethylarsonate [MMA]), other trace elements (aluminum, antimony, arsenic, barium, beryllium, boron, cadmium, chromium, cobalt, copper, iron, lead, lithium, manganese, molybdenum, nickel, selenium, silver, strontium, thallium, vanadium, and zinc), and selected radionuclides (gross alpha- and beta-particle activity [at 72 hours and 30 days], carbon-14, radium isotopes [radium-226 and radium-228], radon-222, tritium, and uranium). Field measurements were made of selected physicochemical (relating to both physical and chemical) properties (oxidation-reduction potential, turbidity, dissolved oxygen concentration, pH, specific conductance, water temperature, and alkalinity) and unfiltered sulfides. Dissolved organic carbon and chemical oxygen demand are presented but not discussed in the report. Physicochemical properties, major ions, and trace elements varied considerably. The pH ranged from 7.2 to 8.1 (median 7.6); specific conductance ranged from 314 to 856 microsiemens per centimeter at 25 degrees Celsius, with a median of 517 microsiemens per centimeter; and alkalinity ranged from 126 to 324 milligrams per liter as calcium carbonate (median 167 milligrams per liter). The range in oxidation-reduction potential was large, from -212 to 244 millivolts, with a median of -84.6 millivolts. The largest ranges in concentration for filtered major ion constituents were obtained for cations sodium and calcium and for anions chloride and bicarbonate (bicarbonate was calculated from the measured alkalinity). Filtered arsenic was detected in all 28 samples, ranging from 0.58 to 15.3 micrograms per liter (median 2.5 micrograms per liter), and exceeded the maximum contaminant level established by the U.S. Environmental Protection Agency of 10 micrograms per liter in 2 of the 28 samples. As(III) was the most frequently detected arsenic specie. As(III) concentrations ranged from less than 0.6 to 14.9 micrograms arsenic per liter. The range in concentrations for the arsenic species As(V) was from less than 0.8 to 3.3 micrograms arsenic per liter. Barium, boron, lithium, and strontium were detected in quantifiable (equal to or greater than the laboratory reporting level) concentrations in all samples and molybdenum in all but one sample. Filtered iron, manganese, nickel, and vanadium were each detected in at least 18 of the 28 samples. All other selected trace elements were each detected in 16 or fewer samples. Radionuclides were detected in most samples. The gross alpha-particle activities at 30 days and 72 hours ranged from R-0.94 to 15.5 and R-1.1 to 17.2 picocuries per liter, respectively ('R' indicates nondetected result less than the sample-specific critical level). The combined radium (radium-226 plus radium-228) concentrations ranged from an estimat
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, Virginia","doi":"10.3133/ds548","collaboration":"Prepared in cooperation with the City of Houston","usgsCitation":"Oden, J.H., Oden, T., and Szabo, Z., 2010, Groundwater quality of the Gulf Coast aquifer system, Houston, Texas, 2007-08: U.S. Geological Survey Data Series 548, v, 65 p., https://doi.org/10.3133/ds548.","productDescription":"v, 65 p.","onlineOnly":"N","additionalOnlineFiles":"N","temporalStart":"2007-06-20","temporalEnd":"2008-09-23","costCenters":[{"id":583,"text":"Texas Water Science Center","active":true,"usgs":true}],"links":[{"id":126167,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ds_548.png"},{"id":14391,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/ds/548/","linkFileType":{"id":5,"text":"html"}}],"scale":"2000000","projection":"Universal Transverse Mercator Projection","country":"United States","state":"Texas","otherGeospatial":"Houston area","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -95.61666666666666,29.666666666666668 ], [ -95.61666666666666,30.116666666666667 ], [ -95.16666666666667,30.116666666666667 ], [ -95.16666666666667,29.666666666666668 ], [ -95.61666666666666,29.666666666666668 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a94e4b07f02db658e61","contributors":{"authors":[{"text":"Oden, Jeannette H. 0000-0002-6473-1553 jhoden@usgs.gov","orcid":"https://orcid.org/0000-0002-6473-1553","contributorId":1152,"corporation":false,"usgs":true,"family":"Oden","given":"Jeannette","email":"jhoden@usgs.gov","middleInitial":"H.","affiliations":[{"id":583,"text":"Texas Water Science Center","active":true,"usgs":true}],"preferred":true,"id":307089,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Oden, Timothy D. toden@usgs.gov","contributorId":1284,"corporation":false,"usgs":true,"family":"Oden","given":"Timothy D.","email":"toden@usgs.gov","affiliations":[],"preferred":true,"id":307090,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Szabo, Zoltan 0000-0002-0760-9607 zszabo@usgs.gov","orcid":"https://orcid.org/0000-0002-0760-9607","contributorId":2240,"corporation":false,"usgs":true,"family":"Szabo","given":"Zoltan","email":"zszabo@usgs.gov","affiliations":[{"id":451,"text":"National Water Quality Assessment Program","active":true,"usgs":true}],"preferred":false,"id":307091,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":98782,"text":"ds534 - 2010 - Groundwater-quality data for the Sierra Nevada study unit, 2008: Results from the California GAMA program","interactions":[],"lastModifiedDate":"2022-07-19T20:21:45.820456","indexId":"ds534","displayToPublicDate":"2010-10-02T00:00:00","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":"534","title":"Groundwater-quality data for the Sierra Nevada study unit, 2008: Results from the California GAMA program","docAbstract":"Groundwater quality in the approximately 25,500-square-mile Sierra Nevada study unit was investigated in June through October 2008, as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The Sierra Nevada study was designed to provide statistically robust assessments of untreated groundwater quality within the primary aquifer systems in the study unit, and to facilitate statistically consistent comparisons of groundwater quality throughout California. The primary aquifer systems (hereinafter, primary aquifers) are defined by the depth of the screened or open intervals of the wells listed in the California Department of Public Health (CDPH) database of wells used for public and community drinking-water supplies. The quality of groundwater in shallower or deeper water-bearing zones may differ from that in the primary aquifers; shallow groundwater may be more vulnerable to contamination from the surface.
In the Sierra Nevada study unit, groundwater samples were collected from 84 wells (and springs) in Lassen, Plumas, Butte, Sierra, Yuba, Nevada, Placer, El Dorado, Amador, Alpine, Calaveras, Tuolumne, Madera, Mariposa, Fresno, Inyo, Tulare, and Kern Counties. The wells were selected on two overlapping networks by using a spatially-distributed, randomized, grid-based approach. The primary grid-well network consisted of 30 wells, one well per grid cell in the study unit, and was designed to provide statistical representation of groundwater quality throughout the entire study unit. The lithologic grid-well network is a secondary grid that consisted of the wells in the primary grid-well network plus 53 additional wells and was designed to provide statistical representation of groundwater quality in each of the four major lithologic units in the Sierra Nevada study unit: granitic, metamorphic, sedimentary, and volcanic rocks. One natural spring that is not used for drinking water was sampled for comparison with a nearby primary grid well in the same cell.
Groundwater samples were analyzed for organic constituents (volatile organic compounds [VOC], pesticides and pesticide degradates, and pharmaceutical compounds), constituents of special interest (N-nitrosodimethylamine [NDMA] and perchlorate), naturally occurring inorganic constituents (nutrients, major ions, total dissolved solids, and trace elements), and radioactive constituents (radium isotopes, radon-222, gross alpha and gross beta particle activities, and uranium isotopes). Naturally occurring isotopes and geochemical tracers (stable isotopes of hydrogen and oxygen in water, stable isotopes of carbon, carbon-14, strontium isotopes, and tritium), and dissolved noble gases also were measured to help identify the sources and ages of the sampled groundwater.
Three types of quality-control samples (blanks, replicates, and samples for matrix spikes) each were collected at approximately 10 percent of the wells sampled for each analysis, 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 from sample collection, handling, and analytical procedures was not a significant source of bias in the data for the groundwater samples. Differences between replicate samples were within acceptable ranges, with few exceptions. 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, groundwater typically is treated, disinfected, or blended with other waters to maintain water quality. Regulatory benchmarks apply to finished drinking 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 groundwater were compared with regulatory and nonregulatory health-based benchmarks established by the U.S. Environmental Protection Agency (USEPA) and CDPH and with nonregulatory aesthetic and technical benchmarks established by CDPH. Comparisons between data collected for this study and drinking-water benchmarks are for illustrative purposes only and do not indicate compliance or noncompliance with regulatory benchmarks.
All organic constituents and most inorganic constituents that were detected in groundwater samples from the 30 primary grid wells in the Sierra Nevada study unit were detected at concentrations less than drinking-water benchmarks.
Of the 150 organic and special-interest constituents analyzed, 21 were detected in groundwater samples; all concentrations were less than regulatory and nonregulatory health-based benchmarks, and most were less than 1/10th of benchmark levels. One or more organic constituents were detected in 37 percent of the primary grid wells, and perchlorate was detected in 27 percent of the primary grid wells.
Most samples analyzed for inorganic and radioactive constituents had concentrations or activities less than regulatory and nonregulatory health-based benchmarks. Nutrients were not detected at concentrations greater than health-based benchmarks. Six of the 30 primary grid wells (20 percent) and 7 of the 53 lithologic grid wells had concentrations of or activities for one or two constituents that were greater than the benchmarks. Constituents present in one or more samples at concentrations or activities greater than health-based benchmarks were arsenic (5 wells, MCL-US), gross alpha particle activity (4 wells, MCL-US), boron (2 wells, NL-CA), fluoride (1 well, MCL-CA), and selenium (1 well, MCL-US). Two of the wells that had high gross alpha particle activities had uranium concentrations (MCL-CA) and uranium activities (MCL-CA) greater than the benchmark levels. Four of the 29 samples analyzed had activities of radon-222 greater than the proposed alternative MCL-US.
Most samples analyzed for inorganic constituents that had nonregulatory, aesthetic-based benchmarks (SMCLs) had concentrations less than these benchmarks. Total dissolved solids concentrations were less than the upper SMCL-CA in all 83 primary and lithologic grid well samples, and TDS concentrations were less than the recommended SMCL-CA in 79 of these samples. Manganese concentrations were greater than the SMCL-CA in 2 of the 30 primary grid wells (7 percent) and in 6 of the 53 lithologic grid wells, and iron concentrations were greater than the SMCL-CA in the same 2 primary grid wells and in 5 of the same lithologic grid wells.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ds534","collaboration":"Prepared in cooperation with the California State Water Resources Control Board","usgsCitation":"Shelton, J.L., Fram, M.S., Munday, C.M., and Belitz, K., 2010, Groundwater-quality data for the Sierra Nevada study unit, 2008: Results from the California GAMA program: U.S. Geological Survey Data Series 534, ix, 82 p., https://doi.org/10.3133/ds534.","productDescription":"ix, 82 p.","additionalOnlineFiles":"N","temporalStart":"2008-01-01","temporalEnd":"2008-12-31","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":126102,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/ds_534.jpg"},{"id":404074,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_94351.htm","linkFileType":{"id":5,"text":"html"}},{"id":14192,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/ds/534/","linkFileType":{"id":5,"text":"html"}}],"projection":"Albers Equal Area Conic Projection","country":"United States","state":"California","otherGeospatial":"Sierra Nevada study unit","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -121.7333,\n 34.7756\n ],\n [\n -117.9167,\n 34.7756\n ],\n [\n -117.9167,\n 40.4297\n ],\n [\n -121.7333,\n 40.4297\n ],\n [\n -121.7333,\n 34.7756\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a94e4b07f02db658ff9","contributors":{"authors":[{"text":"Shelton, Jennifer L. 0000-0001-8508-0270 jshelton@usgs.gov","orcid":"https://orcid.org/0000-0001-8508-0270","contributorId":1155,"corporation":false,"usgs":true,"family":"Shelton","given":"Jennifer","email":"jshelton@usgs.gov","middleInitial":"L.","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":306456,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"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":306457,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Munday, Cathy M. cmunday@usgs.gov","contributorId":3173,"corporation":false,"usgs":true,"family":"Munday","given":"Cathy","email":"cmunday@usgs.gov","middleInitial":"M.","affiliations":[],"preferred":true,"id":306458,"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":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},{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"preferred":true,"id":306455,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ]}