Groundwater, surface-water, and associated quality assurance samples were collected downgradient of an abandoned fire training area and wastewater infiltration beds on western Cape Cod, Massachusetts and analyzed for per- and polyfluoroalkyl substances (PFAS) from 2014-2019. Water-quality properties measured at the time of sample collection include pH, specific conductance, temperature, and dissolved oxygen. Samples were also analyzed for other chemical constituents including major and selected minor inorganic constituents, nutrients, and UV absorbance. Although selected results have been previously published in several data releases, this data release includes the entire suite of field and chemical constituents. PFAS data tables are derived from multiple data sources: Barber and others, 2017; Ruyle and others, 2021; and Tokranov and others, 2021. Other field and chemical data were derived from those sources as well as from Hull and others, 2021 and Repert and others, 2023. PFAS data from different sources were converted to a uniform format. See related external resources for listed citations.