Abstract: Method for in situ removal of a surface-active compound, such as per- and polyfluoroalkyl substances (PFAS), from groundwater are described. A trench is prepared that is arranged to capture groundwater flow. A diffuser is placed in the trench. The trench is backfilled with a permeable, inert solid to an elevation below ground elevation. A platform that floats on water is placed within the trench. The platform includes a perimeter support structure and one or more perforated crossbeams connected to a vacuum source. A compressed gas is provided to the diffuser within the trench to generate a foam containing the surface-active compound above the groundwater. A vacuum is applied through the one or more perforated crossbeams of the platform to collect the foam containing the surface-active compound.

Abstract: Method of removing of per- and polyfluoroalkyl substances (PFAS) from water are described. The methods involve sparging a gas into a container of water; and collecting an aerosol released in a volume above the water.