These data were collected to understand the occurrence of per- and polyfluoroalkyl substances (PFAS) in drinking water samples at selected public water systems in West Virginia identified to have detections for PFAS above laboratory reporting levels in previously collected raw-water samples (McAdoo and others, 2022). These data are stored in the USGS National Water Information System (NWIS) but are not available to the public from that platform because West Virginia State Law §22-26-4, and USGS policy concerning the release of sensitive water related information, prohibits the release of public water system infrastructure location information. This USGS data release serves as the public release of available data for this project and provides a reference location for all users. Description of Available Datasets: These data are available in Excel (.xlsx) files that contain water-quality and quality-assurance results. The Excel files are duplicated as tab-delimited text files to increase accessibility to nonproprietary formats. The files titled WVDEP_PFAS_FinishedWater_Results contain analytical results for PFAS in drinking water collected at 107 sites located in West Virginia. The files titled WVDEP_PFAS_FinishedWater_Quality_Assurance contain associated field blanks, lab blanks, and replicates used for quality control. Lab blanks are used to assess contamination imparted by the analytical process. Field blanks were collected using certified analyte-free water at the sampling point and used to assess possible cross contamination from sampling materials and sampling technique in the field. Field replicates were collected concurrently with the environmental sample and used to understand the variability of results. The attached XML file titled WVDEP_PFAS_FinishedWater_Metadata contains metadata explaining the provenance of the data and should be thoroughly read to understand data structure and limitations. The files titled WVDEP_PFAS_FinishedWater_Data_Dictionary may be used as a reference to explain codes, terms, and abbreviations used in these datasets. The files titled WVDEP_PFAS_Ongoing_Precision_and_Recovery contain quality assurance samples reported by the laboratory which establishes additional confidence in results over time. Sample Collection, Data Validation, and Quality Assurance: Samples were collected at each public water system’s main finished-water sampling point. U.S. Environmental Protection Agency (EPA) Method 533 (Rosenblum and Wendelken, 2019) and EPA Method 537.1 (Shoemaker, 2020) were used to determine PFAS concentrations in all samples. Samples were analyzed at SGS Wilmington in North Carolina. Reporting and detection levels for PFAS results are specific to the analyte, sample matrix, instrumentation, and laboratory performance. Results throughout this dataset that are reported with a "less than" qualifier represent values that were not detected above the reporting level for that sample and specific analyte. The reporting levels shown in this dataset are synonymous with the minimum reporting level as defined by Rosenblum and Wendelken (2019). A combination of field blanks, laboratory method blanks, isotopically labeled compound recoveries, and ongoing precision and recovery samples were used to assess field techniques and validity of the reported results. Finished water results recorded in the file titled WV_PFAS_Finished_Water_Results met all quality assurance criteria, and no additional qualification was required. References: McAdoo, M.A., Connock, G.T., and Messinger, T., 2022, Occurrence of per- and polyfluoroalkyl substances and inorganic analytes in groundwater and surface water used as sources for public water supply in West Virginia: U.S. Geological Survey Scientific Investigations Report 2022–5067, 37 p., https://doi.org/10.3133/sir20225067. Rosenblum, L., and Wendelken, S.C., 2019, Method 533, Determination of per- and polyfluoroalkyl substances in drinking water by isotope dilution anion exchange

Source water for West Virginia’s public water systems is pumped from groundwater aquifers or withdrawn from the state’s rivers and lakes. These systems provide drinking water to a majority of the state’s population and require constant monitoring for known and emerging contaminants. Groundwater contamination from per- and polyfluoroalkyl substances (PFAS) has occurred in West Virginia around industrial facilities and military installations. To understand the potential impact of PFAS contamination in the state’s source waters, West Virginia Department of Environmental Protection (WVDEP) and West Virginia Department of Health and Human Resources (WVDHHR) required information on the state-wide distribution of the contaminant. From May 2019 through May 2021, samples of un-treated water were collected from raw-water supplies at 279 public water systems in West Virginia. Parameters collected at the time of sampling included pH, specific conductance, water temperature, dissolved oxygen, turbidity, and alkalinity. Samples were analyzed at the US Geological Survey (USGS) National Water Quality Laboratory for several inorganic analytes including major ions, trace elements, and nutrients. Samples were also analyzed for 28 PFAS compounds at a contract laboratory that is accredited under the Department of Defense (DoD) Environmental Laboratory Accreditation Program for PFAS analysis compliant with DoD Quality Systems Manual table B15. These data are stored in the USGS National Water Information System (NWIS) but are not available to the public from that platform because West Virginia State Law §22-26-4 and USGS policy concerning the release of sensitive water related information prohibits the release of public water system infrastructure location information. This USGS data release serves as the public release of available data and provides a reference location for associated reports.

Source water for West Virginia’s public water systems is pumped from groundwater aquifers or withdrawn from the state’s rivers and lakes. These systems provide drinking water to a majority of the state’s population and require constant monitoring for known and emerging contaminants. Groundwater contamination from per- and polyfluoroalkyl substances (PFAS) has occurred in West Virginia around industrial facilities and military installations. To understand the potential impact of PFAS contamination in the state’s source waters, West Virginia Department of Environmental Protection (WVDEP) and West Virginia Department of Health and Human Resources (WVDHHR) required information on the state-wide distribution of the contaminant. From May 2019 through May 2021, samples of un-treated water were collected from raw-water supplies at 279 public water systems in West Virginia. Parameters collected at the time of sampling included pH, specific conductance, water temperature, dissolved oxygen, turbidity, and alkalinity. Samples were analyzed at the US Geological Survey (USGS) National Water Quality Laboratory for several inorganic analytes including major ions, trace elements, and nutrients. Samples were also analyzed for 28 PFAS compounds at a contract laboratory that is accredited under the Department of Defense (DoD) Environmental Laboratory Accreditation Program for PFAS analysis compliant with DoD Quality Systems Manual table B15. These data are stored in the USGS National Water Information System (NWIS) but are not available to the public from that platform because West Virginia State Law §22-26-4 and USGS policy concerning the release of sensitive water related information prohibits the release of public water system infrastructure location information. This USGS data release serves as the public release of available data and provides a reference location for associated reports.

This data release provides concentration results for per- and polyfluoroalkyl substances (PFAS) collected by volunteer community members, in tapwater samples from 84 private residences, in select areas within the United States. Samples were collected July 1, 2023, through October 3, 2024. Samples were analyzed at the U.S. Geological Survey National Water Quality Laboratory (NWQL) in Denver, Colorado. Exact site location information for these sites is not available because of privacy concerns.

Data are the source water and treated drinking water concentrations for 17 PFAS. This dataset is associated with the following publication: Boone, J.S., C. Vigo, T. Boone, C. Byrne, J. Ferrario, B. Benson, J. Donohue, J. Simmons, D. Kolpin, E. Furlong, and S. Glassmeyer. Per- and polyfluoroalkyl substances in source and treated drinking waters of the United States.. SCIENCE OF THE TOTAL ENVIRONMENT. Elsevier BV, AMSTERDAM, NETHERLANDS, 653: 359-369, (2019).

Data are the source water and treated drinking water concentrations for 17 PFAS. This dataset is associated with the following publication: Boone, J.S., C. Vigo, T. Boone, C. Byrne, J. Ferrario, B. Benson, J. Donohue, J. Simmons, D. Kolpin, E. Furlong, and S. Glassmeyer. Per- and polyfluoroalkyl substances in source and treated drinking waters of the United States.. SCIENCE OF THE TOTAL ENVIRONMENT. Elsevier BV, AMSTERDAM, NETHERLANDS, 653: 359-369, (2019).

These data were collected in cooperation with the Virginia Department of Environmental Quality (VADEQ) to document the occurrence of Per- and Polyfluoroalkyl Substances (PFAS) in streams and rivers of Virginia. Specifically, this effort was initiated to: 1. Collect and analyze samples for PFAS at USGS-sampling stations in the Chesapeake Bay River Input Monitoring Network and Non-Tidal Network; 2. Collect and analyze samples for PFAS at VADEQ Probabilistic Monitoring stations; 3. Collect and analyze samples for PFAS at additional DEQ-selected locations; and 4. Quality Assure all data collected in accordance with USGS policies and publicly release those data as a citable USGS Data Release. Description of Available Datasets: These data are available in 2 Excel (.xlsx) files that contain water-quality and quality-assurance results. The Excel files are duplicated as tab-delimited text files to increase accessibility to nonproprietary formats. The files titled VA_StateWide_Surface_Water_Results contain analytical results for 166 samples of PFAS in surface water collected at 73 locations in the State. These files also contain associated field blanks, lab blanks, and replicates used for quality control. Lab blanks are used to assess contamination imparted by the analytical process. Field blanks were collected using certified analyte-free water at the sampling point and used to assess possible cross contamination from sampling materials and sampling technique in the field. Field replicates were collected concurrently with the environmental sample and used to understand the variability of results. The attached XML file titled VA_StateWide_Metadata contains metadata explaining the provenance of the data and should be thoroughly read to understand data structure and limitations. The files titled Data_Dictionary may be used as a reference to explain codes, terms, and abbreviations used in these datasets. The files titled Ongoing_Precision_and_Recovery contain quality assurance samples reported by the lab which establishes additional confidence in results over time. Data Validation and Quality Assurance: U.S. Environmental Protection Agency (EPA) Draft Method 1633 (U.S. Environmental Protection Agency, 2021) was used to determine PFAS concentrations in surface water. Samples were analyzed at SGS AXYS in British Columbia, Canada, which is accredited by the U.S. Department of Defense Environmental Laboratory Accreditation Program for analysis of PFAS using Draft Method 1633. Reporting and detection levels for PFAS results are specific to the analyte, sample matrix, instrumentation, and laboratory performance. Results throughout this dataset that are reported with a less than qualifier represent values that were not detected above the reporting level for that sample and specific analyte. The reporting levels show in this dataset are synonymous with the minimum level of quantitation as defined by U.S. Environmental Protection Agency (2021). A combination of field blanks, laboratory method blanks, isotopically labeled compound recoveries, and ongoing precision and recovery samples were used to assess field techniques and validity of the reported results. Three samples for 6:2 fluorotelomersulfonate (6:2 FTS), two samples for perfluorooctanesulfonamide (PFOSA), and one sample for perfluorooctanesulfonate (PFOS) did meet quality assurance criteria. Analytical results for these analytes were rejected in six different samples and are represented in the dataset with an “R” qualifier. References: U.S. Environmental Protection Agency, 2021, Draft Method 1633 - Analysis of Per- and Polyfluoroalkyl Substances (PFAS) in Aqueous, Solid, Biosolids, and Tissue Samples by LC-MS/MS: U.S. Environmental Protection Agency Document EPA 821-D-21-001, 65 p., accessed July 14, 2022, at https://www.epa.gov/system/files/documents/2021-09/method_1633_draft_aug-2021.pdf.

These data were collected in cooperation with the Virginia Department of Environmental Quality (VADEQ) to document the occurrence of Per- and Polyfluoroalkyl Substances (PFAS) in streams and rivers of Virginia. Specifically, this effort was initiated to: 1. Collect and analyze samples for PFAS at USGS-sampling stations in the Chesapeake Bay River Input Monitoring Network and Non-Tidal Network; 2. Collect and analyze samples for PFAS at VADEQ Probabilistic Monitoring stations; 3. Collect and analyze samples for PFAS at additional DEQ-selected locations; and 4. Quality Assure all data collected in accordance with USGS policies and publicly release those data as a citable USGS Data Release. Description of Available Datasets: These data are available in 2 Excel (.xlsx) files that contain water-quality and quality-assurance results. The Excel files are duplicated as tab-delimited text files to increase accessibility to nonproprietary formats. The files titled VA_StateWide_Surface_Water_Results contain analytical results for 166 samples of PFAS in surface water collected at 73 locations in the State. These files also contain associated field blanks, lab blanks, and replicates used for quality control. Lab blanks are used to assess contamination imparted by the analytical process. Field blanks were collected using certified analyte-free water at the sampling point and used to assess possible cross contamination from sampling materials and sampling technique in the field. Field replicates were collected concurrently with the environmental sample and used to understand the variability of results. The attached XML file titled VA_StateWide_Metadata contains metadata explaining the provenance of the data and should be thoroughly read to understand data structure and limitations. The files titled Data_Dictionary may be used as a reference to explain codes, terms, and abbreviations used in these datasets. The files titled Ongoing_Precision_and_Recovery contain quality assurance samples reported by the lab which establishes additional confidence in results over time. Data Validation and Quality Assurance: U.S. Environmental Protection Agency (EPA) Draft Method 1633 (U.S. Environmental Protection Agency, 2021) was used to determine PFAS concentrations in surface water. Samples were analyzed at SGS AXYS in British Columbia, Canada, which is accredited by the U.S. Department of Defense Environmental Laboratory Accreditation Program for analysis of PFAS using Draft Method 1633. Reporting and detection levels for PFAS results are specific to the analyte, sample matrix, instrumentation, and laboratory performance. Results throughout this dataset that are reported with a less than qualifier represent values that were not detected above the reporting level for that sample and specific analyte. The reporting levels show in this dataset are synonymous with the minimum level of quantitation as defined by U.S. Environmental Protection Agency (2021). A combination of field blanks, laboratory method blanks, isotopically labeled compound recoveries, and ongoing precision and recovery samples were used to assess field techniques and validity of the reported results. Three samples for 6:2 fluorotelomersulfonate (6:2 FTS), two samples for perfluorooctanesulfonamide (PFOSA), and one sample for perfluorooctanesulfonate (PFOS) did meet quality assurance criteria. Analytical results for these analytes were rejected in six different samples and are represented in the dataset with an “R” qualifier. References: U.S. Environmental Protection Agency, 2021, Draft Method 1633 - Analysis of Per- and Polyfluoroalkyl Substances (PFAS) in Aqueous, Solid, Biosolids, and Tissue Samples by LC-MS/MS: U.S. Environmental Protection Agency Document EPA 821-D-21-001, 65 p., accessed July 14, 2022, at https://www.epa.gov/system/files/documents/2021-09/method_1633_draft_aug-2021.pdf.

State and local county health departments have detected per- and polyfluoroalkyl substances (PFAS) in groundwater downgradient of airports and military and firefighting training areas in Long Island, New York. However, the occurrence and spatial distribution of PFAS throughout the surficial aquifer is not well established. Shallow groundwater samples were collected in 2018 from two observation well networks; the Sentinel network and Wastewater Treatment Plant groundwater (WTPGW) network. The Sentinel network is an island-wide group of wells screened within the shallow upper glacial (surficial, <100 feet deep) aquifer, which were sampled to assess the occurrence of PFAS in different land-use settings. The WTPGW network consisted of shallow (<60 feet deep) wells located downgradient of decentralized wastewater treatment systems discharging to groundwater, which were sampled to determine if these systems are a source of PFAS to groundwater. Each sample was analyzed for 18 PFAS compounds. This sample collection documents the first Long Island-wide assessment for ambient PFAS contamination within the shallow aquifer system. An extensive quality-assurance and quality-control program developed specifically for the expected low level (<200 nanograms per liter [ng/L]) PFAS environmental concentrations within the groundwater networks revealed no detections of the 18 PFAS compounds analyzed. This indicates that selected equipment, cleaning, sampling, and handling procedures are sufficient to provide data that reflects environmental conditions. Twenty-six of the 37 wells sampled in the Sentinel network had one or more PFAS compounds detected, and up to 8 compounds were detected in a single sample. Ten PFAS compounds have been detected in these samples, with individual compound concentrations ranging from 3.4 to 93 ng/L. Land-use settings for these sample sites varied between medium- and high-density residential and mixed-use commercial properties. Seven monitoring wells surrounding leach fields from three different decentralized wastewater treatment systems (WTPGW network) found four or more PFAS in each groundwater sample. Twelve PFAS compounds have been detected in these samples, with individual compound concentrations ranging from 5 to 620 ng/L. The greatest variety of PFAS was detected at the site that served an assisted living and rehabilitation facility and a hotel while the highest PFAS concentrations were detected at the site that served a strip mall (commercial property).

State and local county health departments have detected per- and polyfluoroalkyl substances (PFAS) in groundwater downgradient of airports and military and firefighting training areas in Long Island, New York. However, the occurrence and spatial distribution of PFAS throughout the surficial aquifer is not well established. Shallow groundwater samples were collected in 2018 from two observation well networks; the Sentinel network and Wastewater Treatment Plant groundwater (WTPGW) network. The Sentinel network is an island-wide group of wells screened within the shallow upper glacial (surficial, <100 feet deep) aquifer, which were sampled to assess the occurrence of PFAS in different land-use settings. The WTPGW network consisted of shallow (<60 feet deep) wells located downgradient of decentralized wastewater treatment systems discharging to groundwater, which were sampled to determine if these systems are a source of PFAS to groundwater. Each sample was analyzed for 18 PFAS compounds. This sample collection documents the first Long Island-wide assessment for ambient PFAS contamination within the shallow aquifer system. An extensive quality-assurance and quality-control program developed specifically for the expected low level (<200 nanograms per liter [ng/L]) PFAS environmental concentrations within the groundwater networks revealed no detections of the 18 PFAS compounds analyzed. This indicates that selected equipment, cleaning, sampling, and handling procedures are sufficient to provide data that reflects environmental conditions. Twenty-six of the 37 wells sampled in the Sentinel network had one or more PFAS compounds detected, and up to 8 compounds were detected in a single sample. Ten PFAS compounds have been detected in these samples, with individual compound concentrations ranging from 3.4 to 93 ng/L. Land-use settings for these sample sites varied between medium- and high-density residential and mixed-use commercial properties. Seven monitoring wells surrounding leach fields from three different decentralized wastewater treatment systems (WTPGW network) found four or more PFAS in each groundwater sample. Twelve PFAS compounds have been detected in these samples, with individual compound concentrations ranging from 5 to 620 ng/L. The greatest variety of PFAS was detected at the site that served an assisted living and rehabilitation facility and a hotel while the highest PFAS concentrations were detected at the site that served a strip mall (commercial property).