On April 17, 2024, the EPA released a final rule designating two perfluorinated chemicals—Perfluorooctanoic Acid (PFOA) and Perfluorooctanesulfonic Acid (PFOS)—as hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA).  EPA also released enforcement guidance explaining how it intends to apply the new listing with respect to certain types of potentially responsible parties.