DC Cir Upholds EPA Rule Designating PFOA, PFOS as CERCLA Hazardous Substances
The D.C. Circuit has rejected industry challenges to the EPA's 2024 final rule designating PFOA and PFOS as 'hazardous substances' under CERCLA, a major decision solidifying the agency's authority to compel cleanup.
On August 18, 2026, the U.S. Court of Appeals for the D.C. Circuit upheld the Environmental Protection Agency’s 2024 rule designating perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) as “hazardous substances” under CERCLA. A panel of Circuit Judges rejected industry arguments that the EPA misinterpreted its statutory authority, violated the Administrative Procedure Act’s notice requirements, and acted arbitrarily and capriciously.
The ruling is a significant victory for the EPA, solidifying the legal foundation for the agency to compel responsible parties to pay for the cleanup of these two “forever chemicals.” The designation triggers stringent reporting obligations for releases exceeding one pound, new disclosure requirements for federal land sales, and hazardous-materials shipping rules. The decision has immediate and direct consequences for industries that manufacture, use, transport, or dispose of products containing PFOA and PFOS, as well as for adjacent sectors like waste management, construction, and water utilities. Although the court noted that numerous regulatory steps must occur before any party faces actual cleanup costs, the decision confirms the EPA’s authority to pursue those actions, exposing a wide array of companies to substantial potential liability. Counsel should advise potentially affected clients to evaluate their CERCLA exposure in light of this ruling.