Field Demonstration to Enhance PFAS Degradation and Mass Removal using Thermally-Enhanced Low-pH ISCO followed by Pump-and-Treat
Remediation of PFAS-impacted sites is a formidable challenge due to the complex mixture of hundreds of PFASs present in aqueous film-forming foams (AFFF), limitations of analytical capabilities, low (part per trillion) levels of concern in the environment, and inherent stability of many perfluoroalkyl substances including perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). The goal of this project is to evaluate the efficacy of in situ thermally-enhanced persulfate oxidation to degrade PFOA and other perfluorinated carboxylic acids (PFCAs) as well as a significant "hidden" long-term source of PFCAs (i.e., polyfluoroalkyl substances that are known PFCA precursors and degrade slowly over time in the environment to form PFCAs). The technology is not expected to oxidize PFOS and other perfluorinated sulfonic acids (PFSAs). Hence, the in situ persulfate oxidation will be paired with pump-and-treat using GAC sorption. Pre-treatment using in situ persulfate oxidation would remove source area mass to the extent practicable and may decrease life-cycle costs and duration of pump-and-treat.
