The U.S. Geological Survey, in cooperation with the Minnesota Pollution Control Agency, conducted a study to determine the occurrence of micropollutants in: (1) shallow groundwater near large subsurface treatment systems and rapid infiltration basins and (2) shallow groundwater and soil from an agricultural field that land applies domestic wastewater. Water samples were analyzed with enzyme linked immunosorbent assay (ELISA) methods at the U.S. Geological Survey Minnesota Water Science Center for carbamazepine and sulfamethoxazole. These data support the following publication: Krall, A.L., Elliott, S.M., Erickson, M.L., and Adams, B.A., 2018, Detecting sulfamethoxazole and carbamazepine in groundwater: Is ELISA a reliable screening tool?, Environmental Pollution, 234, p. 420-428. doi:10.1016/j.envpol.2017.11.065.

The U.S. Geological Survey, in cooperation with the Minnesota Department of Health, conducted a study to determine the occurrence of six unregulated contaminants in source and finished drinking-water samples collected from 67 public water supply systems throughout Minnesota. Minnesota relies on groundwater and surface water sources for drinking water. Land use, such as wastewater discharge and agriculture, is a factor that determines groundwater and surface water quality. The public water supply systems were categorized based on whether the source water is from surface water or groundwater. Groundwater sites were further categorized by expected sources of contamination based on land use: wastewater, agriculture, and mix of wastewater and agriculture. The 67 public water supply systems sampled during this study were composed of 16 surface water (SW), 22 groundwater influenced by wastewater (GWWW), 21 groundwater influenced by agriculture (GWAg), and 8 groundwater influenced by both wastewater and agriculture (GWWW/Ag) facility types. Minnesota finished drinking water from public water supply systems is seldom directly from the source without some degree of treatment. Typically, treatment is to satisfy regulatory requirements or provide aesthetic value rather than designed for the removal of unregulated contaminants. To identify the presence of unregulated contaminants in source and finished drinking water from public water supply facilities, water samples were analyzed for three commonly detected pesticides (atrazine, imidacloprid, and pyrethroids) and three commonly detected pharmaceuticals (caffeine, carbamazepine, and sulfamethoxazole). Concentrations of three target contaminants (atrazine, imidacloprid, and pyrethroids) plus several immunologically similar contaminants and/or three target pharmaceuticals (caffeine, carbamazepine, and sulfamethoxazole) plus several immunologically similar contaminants were determined in source and finished drinking-water samples collected from 22 GWWW, 21 GWAg, 8 GWWW/Ag, and 16 SW public water supply facilities. The target contaminant plus immunologically similar contaminants (as defined by ELISA specifications) are referred to as contaminant groups. Note that each contaminant group may represent a different set of compounds across analyzing laboratories. Samples collected from SW (66 samples) and GWWW/Ag (16 samples) public water supply facilities were analyzed for all six contaminant groups. Samples collected from GWAg (40 samples) facilities were analyzed for the three pesticide groups and samples collected from GWWW (40 samples) facilities were analyzed for the three pharmaceutical groups. A total of 162 water-quality samples were analyzed by three different laboratory entities. All samples were analyzed at the USGS Upper Midwest Water Science Center using the enzyme-linked immunosorbent assay (ELISA) analytical method. All samples were analyzed at the U.S. Geological Survey National Water Quality Laboratory (NWQL) where samples collected for pesticide analysis were analyzed by direct aqueous injection with liquid chromatography and tandem mass spectrometry (LC-MS/MS), except for the target contaminant, atrazine (ATZ1), and samples collected for pharmaceuticals and ATZ1 analysis were analyzed by direct aqueous injection with high performance liquid chromatography and tandem mass spectrometry (HPLC/MS/MS). Samples were also analyzed for select pharmaceuticals at SGS AXYS Services Ltd. (AXYS) by LC-MS/MS. These data are a part of the associated U.S. Geological Survey Scientific Investigations Report 2022-5066 (https://doi.org/10.3133/sir20225066).

The U.S. Geological Survey, in cooperation with the Minnesota Department of Health, conducted a study to determine the occurrence of unregulated contaminants in source and finished drinking waters throughout Minnesota. Minnesota relies on both groundwater and surface water sources for drinking water, which may be vulnerable to influences such as wastewater discharge and/or agricultural activities. Thus, drinking water facilities apply some form of treatment to source waters prior to distribution. Although drinking water treatment is mostly focused on satisfying regulatory requirements, it may provide secondary benefits for removal of unregulated contaminants. In 2019, 2021, and 2022, paired source and finished drinking water was collected from 100 facilities and characterized for select organic contaminants. Samples were analyzed for some combination of alkylphenols, benzotriazoles/benzothiazoles, hormones, illicit drugs, personal care products, pesticides, per- and polyfluoroalkyl substances, pharmaceuticals, plasticizers, and wastewater indicators, depending on potential influences from the watershed.

This data release includes tables and time-series plots of results for volatile organic compounds (VOCs) analyzed in samples of groundwater used for public supply that were collected by the USGS National Water-Quality Assessment (NAWQA) Project and the California State Water Resources Control Board’s Groundwater Ambient Monitoring and Assessment Program Priority Basin Project (GAMA-PBP) during 2013-19; results for associated quality-control samples also are included. All samples were analyzed by the USGS National Water Quality Laboratory (NWQL) using laboratory schedules 4436 and 4437. The table of groundwater data includes VOC results as reported by the laboratory, along with results that represent the application of censoring approaches described in the metadata file and associated journal article. The other seven tables included in this data release contain VOC results for the following types of quality-control samples: field blanks and replicates collected at field sites; laboratory blanks, reagent spikes, and matrix spikes prepared by the NWQL; and third-party blind blanks and blind spikes prepared by the USGS Quality Systems Branch. The tables of VOC results for matrix spikes and field replicates include the paired groundwater results. For convenience, plots are provided of reported VOC detections and concentrations in groundwater samples, field blanks, and laboratory blanks for individual compounds by analysis date. Plots also are provided of recoveries for laboratory reagent spikes, laboratory matrix spikes, and third-party blind spikes for individual VOCs by analysis date. This data release includes 8 tables and 2 series of laboratory results plots: Table1_GroundwaterData2013_2019.csv: VOC results for samples collected by NAWQA and GAMA-PBP of groundwater used for public supply, 2013-19. This table includes VOC results as reported by the laboratory, along with results that represent the application of censoring approaches described in the associated journal article. Results that were rejected or censored for data analysis for reasons described in the metadata document and in the associated journal article are identified using attribute values described in the process steps for this table. Table2_FieldBlankData2013_2019.csv: VOC results for field blanks collected at applicable groundwater sites by NAWQA and GAMA-PBP, 2013-19. Results that were rejected for data analysis for reasons described in the metadata document and in the associated journal article are identified using attribute values described in the process steps for this table. Table3_MatrixSpikeData2013_2019.csv: VOC results for samples collected for laboratory matrix spikes at applicable groundwater sites by NAWQA and GAMA-PBP, 2013-19. Results of paired groundwater samples are included. Results that were rejected for data analysis for reasons described in the metadata document and in the associated journal article are identified using attribute values described in the process steps for this table. Fields needed to calculate spike recovery as described in the data processing steps of the metadata file are included. Table4_FieldRepData2013_2019.csv: VOC results for field replicates collected at groundwater sites by NAWQA and GAMA-PBP, 2013-19. Results of paired groundwater samples are included. Fields needed to calculate variability in detection and (or) concentration as described in the data processing steps of the metadata file are included. Table5_LabBlankData2013_2019.csv: VOC results for laboratory blanks prepared by the National Water Quality Laboratory, 2013-19. Table6_LabReagentSpikeData2013_2019.csv: VOC results for laboratory reagent spikes prepared by the National Water Quality Laboratory, 2013-19. Table7_QSBBlindBlankData2016_2019.csv: VOC results for third-party blind blanks prepared by the Quality Systems Branch, 2016-19. Table8_QSBBlindSpikeData2013_2019.csv: VOC results for third-party blind spikes prepared by the Quality Systems Branch,

The U.S. Geological Survey, in cooperation with the Minnesota Department of Health, conducted a study to determine the occurrence of unregulated contaminants in source and finished drinking waters throughout Minnesota. Minnesota relies on both groundwater and surface water sources for drinking water, which may be vulnerable to influences such as wastewater discharge and/or agricultural activities. Thus, drinking water facilities apply some form of treatment to source waters prior to distribution. Although drinking water treatment is mostly focused on satisfying regulatory requirements, it may provide secondary benefits for removal of unregulated contaminants. In 2019, 2021, and 2022, paired source and finished drinking water was collected from 100 facilities and characterized for select organic contaminants. Samples were analyzed for some combination of alkylphenols, benzotriazoles/benzothiazoles, hormones, illicit drugs, personal care products, pesticides, per- and polyfluoroalkyl substances, pharmaceuticals, plasticizers, and wastewater indicators, depending on potential influences from the watershed.

The U.S. Geological Survey, in cooperation with the Minnesota Department of Health, conducted a study to determine the occurrence of unregulated contaminants in source and finished drinking waters throughout Minnesota. Minnesota relies on both groundwater and surface water sources for drinking water, which may be vulnerable to influences such as wastewater discharge and/or agricultural activities. Thus, drinking water facilities apply some form of treatment to source waters prior to distribution. Although drinking water treatment is mostly focused on satisfying regulatory requirements, it may provide secondary benefits for removal of unregulated contaminants. In 2019, 2021, and 2022, paired source and finished drinking water was collected from 100 facilities and characterized for select organic contaminants. Samples were analyzed for some combination of alkylphenols, benzotriazoles/benzothiazoles, hormones, illicit drugs, personal care products, pesticides, per- and polyfluoroalkyl substances, pharmaceuticals, plasticizers, and wastewater indicators, depending on potential influences from the watershed.

The Marcellus Shale Energy and Environment Laboratory (MSEEL) is part of the Northeast Natural Energy LLC (NNE) production facility on the Monongahela River in Monongalia County, West Virginia, USA. Natural gas extraction in the area creates large volumes of wastewater that may contain chemical compounds that pose risks to humans, animals, and the environment. The U. S. Geological Survey (USGS) has been studying the organic compounds in water produced from shale gas wells and in 2014, NNE started drilling two production wells in the Marcellus Shale. The well, MIP (Morgantown Industrial Park) -5H, was completed the following year. Samples were collected from this well. Large volumes of wastewater fluids were produced from this well and contain a mixture of chemicals added during hydraulic fracturing of the formation and chemical constituents from the host rocks. The original hydraulic fracturing fluids and the wastewater contain organic materials that could be toxic or pose risks to the environment if leaked, spilled, or improperly disposed of. This project was designed to collect comprehensive data from multiple sample types, including Monongahela River water, wastewater collected at the separator (during the flowback and produced-water phase), storage tank wastewater, and field blanks. Water samples for the analyses contained in this release were collected from July 2015 through December 2018. Samples of Monongahela River water were collected from a lined holding pond adjacent to the MIP well pad on November 5, 2015. Wastewater was intermittently sampled from the MIP-5H separator on the well pad from December 10, 2015, to December 6, 2018. The wastewater produced during the first two weeks of production was labeled as flowback water until December 23, 2015, then the wastewater produced after this date was defined as produced water. A storage tank at the well pad site was sampled on December 6, 2018. This data release contains non-target liquid chromatography/high-resolution mass spectrometry data.

The Marcellus Shale Energy and Environment Laboratory (MSEEL) is part of the Northeast Natural Energy LLC (NNE) production facility on the Monongahela River in Monongalia County, West Virginia, USA. Natural gas extraction in the area creates large volumes of wastewater that may contain chemical compounds that pose risks to humans, animals, and the environment. The U. S. Geological Survey (USGS) has been studying the organic compounds in water produced from shale gas wells and in 2014, NNE started drilling two production wells in the Marcellus Shale. The well, MIP (Morgantown Industrial Park) -5H, was completed the following year. Samples were collected from this well. Large volumes of wastewater fluids were produced from this well and contain a mixture of chemicals added during hydraulic fracturing of the formation and chemical constituents from the host rocks. The original hydraulic fracturing fluids and the wastewater contain organic materials that could be toxic or pose risks to the environment if leaked, spilled, or improperly disposed of. This project was designed to collect comprehensive data from multiple sample types, including Monongahela River water, wastewater collected at the separator (during the flowback and produced-water phase), storage tank wastewater, and field blanks. Water samples for the analyses contained in this release were collected from July 2015 through December 2018. Samples of Monongahela River water were collected from a lined holding pond adjacent to the MIP well pad on November 5, 2015. Wastewater was intermittently sampled from the MIP-5H separator on the well pad from December 10, 2015, to December 6, 2018. The wastewater produced during the first two weeks of production was labeled as flowback water until December 23, 2015, then the wastewater produced after this date was defined as produced water. A storage tank at the well pad site was sampled on December 6, 2018. This data release contains non-target liquid chromatography/high-resolution mass spectrometry data.

The Marcellus Shale Energy and Environment Laboratory (MSEEL) is part of the Northeast Natural Energy LLC (NNE) production facility on the Monongahela River in Monongalia County, West Virginia, USA. Natural gas extraction in the area creates large volumes of wastewater that may contain chemical compounds that pose risks to humans, animals, and the environment. The U. S. Geological Survey (USGS) has been studying the organic compounds in water produced from shale gas wells and in 2014, NNE started drilling two production wells in the Marcellus Shale. The well, MIP (Morgantown Industrial Park) -5H, was completed the following year. Samples were collected from this well. Large volumes of wastewater fluids were produced from this well and contain a mixture of chemicals added during hydraulic fracturing of the formation and chemical constituents from the host rocks. The original hydraulic fracturing fluids and the wastewater contain organic materials that could be toxic or pose risks to the environment if leaked, spilled, or improperly disposed of. This project was designed to collect comprehensive data from multiple sample types, including Monongahela River water, wastewater collected at the separator (during the flowback and produced-water phase), storage tank wastewater, and field blanks. Water samples for the analyses contained in this release were collected from July 2015 through December 2018. Samples of Monongahela River water were collected from a lined holding pond adjacent to the MIP well pad on November 5, 2015. Wastewater was intermittently sampled from the MIP-5H separator on the well pad from December 10, 2015, to December 6, 2018. The wastewater produced during the first two weeks of production was labeled as flowback water until December 23, 2015, then the wastewater produced after this date was defined as produced water. A storage tank at the well pad site was sampled on December 6, 2018. This data release contains non-target liquid chromatography/high-resolution mass spectrometry data.

Surface-water organic contaminant concentration data for targeted chemical analysis of over 800 organic analytes in surface water from 38 stream site representing national gradients in urban and agricultural land use in the USA during 2012-14. ScienceBase Data Release for journal article entitled, "Expanded Target-Chemical Analysis Reveals Extensive Mixed-Organic-Contaminant Exposure in USA Streams"