Subsurface transport potential of perfluoroalkyl acids (PFAAs): Column experiments and modeling.

Transport of ten perfluoroalkyl acids (PFAAs) was studied with one-dimensional (1-D) saturated column experiments using four soil types with an organic carbon fraction (f) range of ~0-0.045. Columns were operated under conditions relevant to aqueous film-forming foam (AFFF)-impacted fire protection training areas to determine the ability of equilibrium transport parameters to describe 1-D PFAA transport, if rate-limited sorption influences PFAA transport, and if kinetic parameters can be used to evaluate factors causing rate-limited sorption.

Evidence of remediation-induced alteration of subsurface poly- and perfluoroalkyl substance distribution at a former firefighter training area.

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 Koc 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.

Metal release from sandstones under experimentally and numerically simulated CO2 leakage conditions.

Leakage of CO2 from a deep storage formation into an overlying potable aquifer may adversely impact water quality and human health. Understanding CO2-water-rock interactions is therefore an important step toward the safe implementation of geologic carbon sequestration. This study targeted the geochemical response of siliclastic rock, specifically three sandstones of the Mesaverde Group in northwestern Colorado.

Geochemical implications of brine leakage into freshwater aquifers.

CO(2) injection into deep saline formations as a way to mitigate climate change raises concerns that leakage of saline waters from the injection formations will impact water quality of overlying aquifers, especially underground sources of drinking water (USDWs). This paper aims to characterize the geochemical composition of deep brines, with a focus on constituents that pose a human health risk and are regulated by the U.S.