chemical concentrations. This dataset is associated with the following publication: Falzone, S., C. Schaefer, E. Siegenthaler, K. Keating, D. Werkema, and L. Slater. Geophysical Signatures of Soil AFFF Contamination from Spectral Induced Polarization and Low Field Nuclear Magnetic Resonance Methods. JOURNAL OF CONTAMINANT HYDROLOGY. Elsevier Science Ltd, New York, NY, USA, 260: 104268, (2024).

Per- and polyfluoroalkyl substances (PFAS) chemicals are known to strongly sorb onto soils when being transported downward through the vadose zone. The degree to which this sorption occurs depends on the length of the specific PFAS molecular chain and the properties of the soil. The properties with greatest influence on the soils PFAS sorption potential are percent silt and clay, and organic matter content (Fabregat-Palau and others, 2021), which have small size fractions that provide more sorption sites. In addition to sorption, the estimated long-term mean-annual vertical transport velocity of any chemical in a soil zone can be calculated given the recharge rate and volumetric water content. The latter can be calculated given the recharge rate, percent clay, and saturated hydraulic conductivity (Clapp and Hornberger, 1978). Also, the retardation factor can be calculated if the bulk density and water content are known. Given these requirements, raster data of these soil properties, in addition to several others, were downloaded from the Polaris Soils database made available in 2019, and used in preliminary analyses to assess the vulnerability of shallow groundwater to perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) contamination at a national scale. The POLARIS data that were chosen in this study were percent silt, percent clay, percent sand, percent organic matter, saturated water content, saturated hydraulic conductivity, and bulk density. Rasters of these soil properties for each of the six depth layers included in the database were created for the contiguous United States (see compressed files percentclay.7z, percentsilt.7z, percentsand.7z, bulkdensity_bd.7z, saturatedhydraulicconductivity_ksat.7z, soilwatercontent_theta_s.7z, and soilorganicmatter_om.7z in Child Item section). The resulting rasters were used in analyses to create rasters of PFOS and PFOA sorption distribution coefficients (Kd values) as well as a classified soil raster based on the classic ternary diagram of the U.S. Department of Agriculture (Davis and Bennett, 1927). A 250-m resolution was chosen to be coincident with the 1-kilometer resolution grid of the USGS national hydrogeologic framework (Brassington and Younger, 2010). The POLARIS data are well represented at this, and even finer, resolutions (Chaney and others 2016). Future analyses to be conducted include combining these files with other existing rasters of mean-annual recharge and depth to the water table (Zell and Sanford, 2020) to develop a raster representing the vulnerability of shallow groundwater to PFOA and PFOS contamination for the contiguous United States.

In the current study, soils obtained from a collaboration with a fluorotelomer-based polymer manufacturing facility in New Jersey, USA were subjected to both targeted and non-targeted analysis of PFCA precursors. Surface soil samples were screened for twenty-two volatile PFAS precursors using GC-positive chemical ionization (PCI)-MS (targeted) including eight nFTOHs, four secondary FTOHs (sFTOHs), six FT-acrylates (FT-Acrs) and four FT-acetates (Table S1) as well as the concentrations of their terminal transformation products (i.e., PFCAs, n=16) determined by LC-MS/MS. Targeted analysis confirmed the presence of these series, specifically the nFTOHs, and non-targeted analysis highlighted additional known and novel industrial manufacturing by-products likely unintentionally produced during the FT-polymerization process. This dataset is associated with the following publication: Henderson, W., M. Evich, J. Washington, T. Ward, B. Schumacher, J. Zimmerman, Y. Kim, E. Weber, A. Williams, M. Smeltz, and D. Glinski. Analysis of Legacy and Novel Neutral Per- and Polyfluoroalkyl Substances in Soils from an Industrial Manufacturing Facility. ENVIRONMENTAL SCIENCE & TECHNOLOGY. American Chemical Society, Washington, DC, USA, 58(24): 10729–10739, (2024).

Per- and polyfluoroalkyl substances (PFAS) and related chemical and physical data are presented from shallow soil and groundwater at two sites in New Hampshire. The two sites, the former Brentwood Fire Training Area and White Farm, were selected because materials known to contain PFAS were used at each site. White Farm is an active farm where biosolids have been applied for several years. At the former Brentwood Fire Training Area, PFAS-containing aqueous film-forming foams were applied as part of regular fire training exercises. At each site, soil samples were collected in a gridded pattern over the site. Soil horizons within the sampling intervals were described using the National Soil Survey Center Natural Resources Conservation Service U.S. Department of Agriculture Field Book for Describing and Sampling Soils (Schoeneberger and others, 2012). Analyses included 36 PFAS compounds, 36 PFAS compounds post-total oxidizable precursor assay (TOPA), total organic carbon (TOC), moisture content, pH, autoclaved-citrate extractable protein, grain size, major ions and other physical and physicochemical parameters. Groundwater samples were collected and analyzed for PFAS during two sampling events at each site from temporary wells, existing monitoring wells, and/or pushpoint samplers. Additionally, a lysimeter was installed at the center of each site and a composite sample through the duration of each water sampling event (approximately 7 days) was collected. Quality control samples included source-solution blanks, equipment blanks, and replicates. Reference: Schoeneberger, P.J., Wysocki, D.A., Benham, E.C., and Soil Survey Staff, 2012, Field book for describing and sampling soils, Version 3.0: Natural Resources Conservation Service, National Soil Survey Center, Lincoln, NE.

This data release contains concentration and isotope-dilution standard (IDS) recovery data from individual samples that are summarized and interpreted in the U.S. Geological Survey (USGS) Techniques and Methods (T&M) Report "Determination of Per- and Polyfluoroalkyl Substances in Water by Direct Injection of Matrix-Modified Centrifuge Supernatant and Liquid Chromatography-Tandem Mass Spectrometry with Isotope Dilution". This includes results from method validation experiments and quality control data collected in conjunction with custom sample analysis for customers using USGS National Water Quality Laboratory (NWQL) Laboratory Code 9660 between December 15, 2020 and March 2, 2022. Results in the T&M Report are presented as statistical summaries of data from multiple related samples, the individual sample data that underlie those summaries are presented here.

The California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project (GAMA-PBP) analyzed for per-and polyfluoroalkyl substances (PFAS) in groundwater samples collected from domestic and public drinking water supply wells in California. GAMA-PBP is a cooperative program between the U.S. Geological Survey and the California State Water Resources Control Board. This data release contains data for samples collected from May 2019 through December 2022 and includes revisions to earlier data (Kent, 2021) that were either screened or removed after analysis of quality-control data. Please see the quality-control and other descriptions of the data in the processing steps in the xml file. Subsequent updates will include data for samples collected after December 2022. Data are also publicly available for download from Jurgens and others (2018). The dataset consists of 4 tables. Table 1 lists the names and abbreviations of the twenty-eight PFAS constituents analyzed. Table 2 contains information about each site visited, including location and well depth information. Table 3 contains results for each PFAS constituent analyzed and includes quality-control sample results where applicable. Table 4 contains a list of every sample collected at each site and has a summary of all the PFAS detections for each sample. This data release supercedes previous PFAS data release versions reported by Kent (2021). Version 2.0 of the previous data release (Kent, 2021) contained data for samples collected from May 2019 through June 2021. Data from Kent (2021) is available upon request from the authors of this data release. References: Kent, R.H., 2021, Data sets for: Sampling for Per-and Polyfluoralkly Substances (PFAS) by the GAMA Priority Basin Project (GAMA-PBP)(2019-2021) (ver. 2.0, October 2021): U.S. Geological Survey data release, https://doi.org/10.5066/P92IPRJD. Jurgens, B.C., Jasper, M., Nguyen, D.H., and Bennett, G.L., 2018, USGS CA GAMA-PBP Groundwater Quality Results--Assessment and Trends: U.S. Geological Survey website, available at https://doi.org/10.5066/P91WJ2G1.

Data from a laboratory study undertaken at the U.S. Geological Survey to investigate solid/water partitioning of per- and polyfluoroalkyl substances (PFAS) in New Hampshire soils and biosolids are presented here. Soils and biosolids used for the experiments were collected using PFAS-free sampling equipment, air dried, gently homogenized, and sieved (soils only). Soil samples were collected from locations with known PFAS contamination (n = 5) and nearby sites with similar soil characteristics but low expected PFAS concentrations (n = 4). Finished biosolids were collected directly from facilities at the final stage of processing and before distribution. Air-dried soils and biosolids were then used for a series of batch and column experiments to determine water/solid distribution coefficient (Kd) values. This study investigated the impact of pH, ionic strength, adsorption versus desorption, soil/biosolid type, experimental setup (batch versus column), and influence of sodium azide on Kd values. All batch and column experiments were run for 10 days as determined by a 16-day kinetics test. The dataset presented here includes concentration of PFAS, concentration of PFAS post total oxidizable precursor assay (TOPA), pH, moisture content, total organic carbon concentrations, aluminum concentrations, iron concentrations, sodium concentrations, cation exchange capacity, anion exchange capacity, grain size, and protein concentrations for the unprocessed soil and biosolids collected from the site (soils) or facility (biosolids). These are denoted as "Environmental - Biosolid" or "Environmental - Soil" samples in the data release. The dataset also includes the solid and water results (PFAS, TOPA, pH, specific conductivity, dissolved organic carbon, major anions, and metals) from the batch and column experiments, along with the calculated Kd values. Calculated Kd values are presented for every PFAS compound with detections in the solid and water phases and, with caution, can be used to help constrain estimates for PFAS mobility in the New Hampshire environment.

The U.S. Geological Survey Groundwater Ambient Monitoring and Assessment-Priority Basin Project (USGS GAMA-PBP) collected samples to be analyzed for per-and polyfluoroalkyl substances (PFAS) from domestic and public supply wells from May 2019 to June 2021. The datasets presented here include identification of the 28 PFAS constituents monitored by the project, Identification and brief characterization of the 395 GAMA-PBP wells for which samples were analyzed for PFAS during the study period, and analytical results for those groundwater samples, along with results for quality control samples.

Concentrations of tetrachloroethylene (PCE) in interpolated soil surface boundary points at the Vienna Wells Site: Maries County, Missouri. This boundary is composed of points with an assumed PCE concentration of 11 micrograms per kilogram (detection limit) and was used with the soil sample dataset (doi: 10.5066/F71835D8) to create an interpolated surface.

Data for per- and polyfluoroalkyl substances (PFAS) and related chemical and physical characteristics are presented from 30 soil sampling locations within the State of New Hampshire. A total of 15 sites were chosen based on the results of sampling efforts published in Santangelo and others(2022). Sites with relatively high concentrations of PFAS observed during the first study were selected for resampling to better understand the range of concentrations of PFAS in the area. At each of the 15 sites, soil samples were collected as near to the original site as possible (site A), and a second set of soil samples were collected at a secondary location (site B) 50 to 600 feet away from the original location for a total of 30 sampling locations. At each location, soils were collected in 6-inch intervals to a maximum depth of 12 inches. Soil horizons were described using the National Soil Survey Center Natural Resources Conservation Service U.S. Department of Agriculture Field Book for Describing and Sampling Soils (Schoeneberger and others, 2012). Analyses included 36 PFAS compounds, total organic carbon (TOC), moisture content, pH, and autoclaved-citrate extractable protein. Quality control samples included source-solution blanks, equipment blanks, and replicates (duplicates). References: Santangelo, L.M., Tokranov, A.K., Welch, S.M., Schlosser, K.E.A., Marts, J.M., Drouin, A.F., Ayotte, J.D., Rousseau, A.E., and Harfmann, J.L., 2022, Statewide survey of shallow soil concentrations of per- and polyfluoroalkyl substances (PFAS) and related chemical and physical data across New Hampshire, 2021: U.S. Geological Survey data release, https://doi.org/10.5066/P9KG38B5. Schoeneberger, P.J., Wysocki, D.A., Benham, E.C., and Soil Survey Staff, 2012, Field book for describing and sampling soils, Version 3.0: Natural Resources Conservation Service, National Soil Survey Center, Lincoln, NE, https://www.nrcs.usda.gov/resources/guides-and-instructions/field-book-for-describing-and-sampling-soils.