This data release presents chemical and biological results from an investigation of the uptake of per- and polyfluoroalkyl substances (PFAS) from groundwater contaminated by fire training activities on Cape Cod, Massachusetts. Exposure experiments were conducted from August 29 to September 21, 2018 using groundwater from a relatively uncontaminated reference site and a fire training area contaminated site. To assess the uptake characteristics of the PFAS mixtures present in the 2 groundwater sources, 21-day mobile laboratory exposure experiments were conducted using fathead minnows (Pimephales promelas), polar organic chemical integrative samplers, and polyethylene tube samplers. Freshwater mussel (Ligumia subrostrata) exposure experiments were conducted for 14 days, beginning on day 7 of the fish and passive sampler exposures. Groundwater samples were collected daily (with a few exceptions). Samples for male fish and passive samplers were collected on days 0, 4, 7, 14, and 21. Samples for female fish were collected on days 0, 7, 14, and 21. The 14 day mussel exposures began on day 7 of the fish and passive sampler exposures, and mussel samples were collected on days 7, 11, 14, and 21. Groundwater site locations and well characteristics are presented in Table 1. Information on the various PFAS and co-occurring contaminants measured in the different media are presented in Table 2. Quality assurance results for PFAS analysis of the different media are presented in Table 3. Results for PFAS in groundwater are presented in Table 4. Results for co-occurring contaminants in groundwater are presented in Table 5. Results for fish biomarkers are presented in Table 6. Results for PFAS in male and female fish tissue are presented in Table 7. Results for PFAS in mussel tissue are presented in Table 8. Results for PFAS in polar organic chemical integrative samplers are presented in Table 9. Results for PFAS in polyethylene tube samplers are presented in Table 10.