The CERCLA Hazardous Substance Designation
In April 2024, the EPA finalized the designation of PFOA and PFOS as hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), commonly known as Superfund. This designation is one of the most consequential regulatory actions in PFAS policy, as it enables EPA to compel responsible parties to clean up contaminated sites and recover cleanup costs.
Under CERCLA, any party that released a hazardous substance — including manufacturers, users, and in some cases property owners — can be held strictly, jointly, and severally liable for cleanup costs regardless of fault. This means any one responsible party can be required to pay the full cost of remediation.
Who Is Exposed to Liability
PFAS manufacturers — primarily 3M and DuPont/Chemours — face the most significant liability under the Superfund designation. Both companies have already settled major lawsuits related to PFAS contamination, but the Superfund designation opens additional avenues for government cost recovery.
Municipal and airport fire departments, the military, and industrial facilities that used AFFF foam are also potentially liable as users who released PFAS into the environment. The EPA has signaled it will focus enforcement on largest contributors while providing liability protections for certain municipalities and wastewater treatment facilities that received PFAS-contaminated industrial discharges.
Cleanup Priorities and Challenges
Thousands of sites across the United States have documented PFAS contamination, far exceeding available Superfund resources. EPA must prioritize sites based on risk to human health and vulnerable populations. Sites near drinking water sources serving large populations are expected to receive early attention.
PFAS contamination presents unique cleanup challenges due to the compounds’ mobility in groundwater, resistance to degradation, and low cleanup thresholds mandated by drinking water standards. Technologies including in-situ chemical oxidation, electrochemical treatment, and thermal destruction are being evaluated at pilot scale for cost-effective remediation.