Evidence of Remediation-Induced Alteration of Subsurface Poly- and Perfluoroalkyl Substance Distribution at a Former Firefighter Training Area

• Published in: Environmental science & technology 2014-06, Vol.48 (12), p.6644-6652
• Main Authors: McGuire, Meghan E, Schaefer, Charles, Richards, Trenton, Backe, Will J, Field, Jennifer A, Houtz, Erika, Sedlak, David L, Guelfo, Jennifer L, Wunsch, Assaf, Higgins, Christopher P
• Format: Article
• Language: English
• Subjects: Alkanesulfonic Acids - analysis; Applied sciences; Biological and physicochemical properties of pollutants. Interaction in the soil; Chemicals; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Environmental Restoration and Remediation; Exact sciences and technology; Firefighters; Fluorocarbons - analysis; Geography; Groundwater; Groundwater - chemistry; Groundwater pollution; Groundwaters; Natural water pollution; Perfluoroalkyl & polyfluoroalkyl substances; Pollution; Pollution control; Pollution studies; Pollution, environment geology; Soil - chemistry; Soil and sediments pollution; Soil Pollutants - analysis; South Dakota; Sulfonic Acids - analysis; Surface Properties; Water Pollutants, Chemical - analysis; Water treatment and pollution
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es5006187

Poly- and perfluoroalkyl substances (PFASs) are a class of fluorinated chemicals that are utilized in firefighting and have been reported in groundwater and soil at several firefighter training areas. In this study, soil and groundwater samples were collected from across a former firefighter training area to examine the extent to which remedial activities have altered the composition and spatial distribution of PFASs in the subsurface. Log K oc values for perfluoroalkyl acids (PFAAs), estimated from analysis of paired samples of groundwater and aquifer solids, indicated that solid/water partitioning was not entirely consistent with predictions based on laboratory studies. Differential PFAA transport was not strongly evident in the subsurface, likely due to remediation-induced conditions. When compared to the surface soil spatial distributions, the relative concentrations of perfluorooctanesulfonate (PFOS) and PFAA precursors in groundwater strongly suggest that remedial activities altered the subsurface PFAS distribution, presumably through significant pumping of groundwater and transformation of precursors to PFAAs. Additional evidence for transformation of PFAA precursors during remediation included elevated ratios of perfluorohexanesulfonate (PFHxS) to PFOS in groundwater near oxygen sparging wells.