Method and apparatus for removal of per- and polyfluoroalkyl substances (pfas) from groundwater

Abstract

A decontamination method for subsurface aquifers having per- and polyfluoroalkyl substances (PFAS) contaminants by injecting gas through a screened well or open tube through a porous media to form buoyant material where the PFAS contaminants accumulate on and/or in the buoyant material and rise to the water table or top of the aquifer with PFAS that desorbs from the buoyant material and concentrates in the shallow groundwater, and extracting or sequestering the groundwater near the water table or top of the confined aquifer and/or collecting the buoyant material for treatment. The method may include treatment of aquifer material consisting of gravel, sand, silt, clay, or fractured geologic media, or combination, and extraction through phytoremediation, groundwater extraction wells, wellpoint systems, or groundwater extraction trenches and include a seal and/or check valve near the water table in the trench to selectively permit water and buoyant material to flow upward.