For several years, many in the legal and environmental communities have wondered what the reach of enforcement by the EPA might be if the agency were to determine that per- and polyfluoroalkyl substances (PFAS) were hazardous substances under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA, or, more informally known as Superfund). EPA proposed Superfund designations in 2022 for two PFAS (perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS)). Superfund provides a mechanism for the EPA to force the parties responsible for the contamination at a designated Superfund site to either perform the cleanups with EPA oversight or reimburse the EPA if the EPA leads the cleanup activities. To date, EPA has identified nearly 200 Superfund sites where PFAS are present.

In October, as reported by Inside EPA, EPA’s chief of the Resource Conservation and Recovery Office’s cleanup programs branch, Charlotte Mooney, spoke about PFAS at Superfund sites at the Association of State and Territorial Solid Waste Management Officials’ annual conference. During that session, Mooney confirmed that the EPA’s proposed designation of PFAS as a hazardous substance could lead the agency to reopen sites where cleanup had previously been considered complete. Mooney stated the analysis would be done on a “case-by-case basis” but the criteria for that analysis has not been disclosed to date.