The U.S. Environmental Protection Agency ("EPA") announces the finalization of a rule designating PFOA and PFOS as CERCLA hazardous substances.

On April 19, 2024, EPA announced its highly anticipated final rule designating two polyfluoroalkyl substances ("PFAS")—perfluorooctanoic acid ("PFOA") and perfluorooctanesulfonic acid ("PFOS")—as "hazardous substances" under the Comprehensive Environmental Response, Compensation, and Liability Act ("CERCLA"), making sites contaminated with PFOA and PFOS subject to response actions conducted under the auspices of CERCLA.

PFAS, including PFOA and PFOS, are synthetic chemicals with wide commercial and industrial applications, including firefighting foams, greaseproof food wrapping, nonstick cookware, water-repellent fabrics, carpets, and textiles.

CERCLA, also known as "Superfund," authorizes the federal government to take response actions at sites to address releases or threatened releases of hazardous substances, or to order potentially responsible parties ("PRPs") to do or pay for that work. PRPs may include current and former site owners and operators, as well as certain generators and transporters of hazardous substances. Accordingly, under the final rule, agencies or other parties conducting CERCLA response actions to address PFOS and PFOA contamination will be permitted to seek to recover the costs of the response action from PRPs.

In addition, under CERCLA, any person in charge of a facility or vessel must immediately report a release of a hazardous substance at or above its reportable quantity to federal, state, tribal, and local authorities as soon as he or she has knowledge of any such release. EPA finalized a reportable quantity of one pound or more in a 24-hour period for PFOA and PFOS. Additionally, the CERCLA hazardous substance designation triggers additional reporting requirements under the Emergency Planning and Community Right-to-Know Act ("EPCRA"). EPCRA mandates reporting requirements on the storage, usage, and release of CERCLA-designated hazardous substances, including follow-up written reporting within 30 days of a reportable release.

In conjunction with the final rule, EPA released a PFAS Enforcement Discretion and Settlement Policy, indicating it will consider exercising discretion to refrain from bringing CERCLA actions against a number of categories of potential PRPs, including public water systems, publicly owned treatment works, and publicly owned or operated municipal solid waste landfills.

The final rule will be effective 60 days after publication in the Federal Register. The final rule is expected to have significant and costly consequences on Superfund liability. Moreover, it is expected that the rule will be subject to legal challenge, which could result in an order to stay its imposition until the challenges are resolved.