Background
In 2024, the Environmental Protection Agency designated perfluorooctanoic acid and perfluorooctanesulfonic acid—PFOA and PFOS—as “hazardous substances” under the Comprehensive Environmental Response, Compensation, and Liability Act. EPA relied on studies linking the chemicals to cancer, developmental effects, cardiovascular conditions, and other harms, as well as evidence that they persist in the environment and accumulate in human bodies.
Seven industry groups whose members use, transport, or discharge PFOA or PFOS petitioned for review. They argued that EPA misread CERCLA’s requirement that a substance “may present substantial danger,” failed to provide adequate notice of its final cost-benefit analysis, performed that analysis arbitrarily, and improperly regulated despite uncertainty about cleanup sites, costs, liability, and other consequences.
The Court’s Holding
The D.C. Circuit denied the petitions. Interpreting CERCLA independently under Loper Bright, the court held that “may present substantial danger” covers a scientifically possible, serious, and real risk of harm; EPA did not have to establish that substantial harm would certainly follow every release. That interpretation was consistent with CERCLA’s text and context and raised no nondelegation or due-process problem.
The court also held that EPA satisfied the Administrative Procedure Act. Its final Regulatory Impact Analysis was a logical outgrowth of the proposed rule and earlier Economic Assessment, and its additional data and quantitative estimates supplemented the analysis in response to public comments. EPA reasonably evaluated cleanup costs and benefits, industry effects, and small-business impacts, and adequately explained why acknowledged uncertainties did not prevent designation at this initial stage. The court assumed without deciding that CERCLA required EPA to consider costs.
Key Takeaways
- CERCLA permits EPA to designate a substance when its release poses a scientifically possible substantial danger; certainty of harm is not required.
- A final quantitative analysis may satisfy APA notice requirements when it logically develops from an earlier qualitative analysis and responds to comments requesting greater quantification.
- Uncertainty about future site-specific cleanups and liability did not invalidate the designation because CERCLA requires additional investigations, cost reviews, public participation, and liability determinations before cleanup costs are imposed.
Why It Matters
The decision leaves PFOA and PFOS designated as CERCLA hazardous substances, preserving reporting and transportation obligations and allowing EPA, governments, and private parties to invoke CERCLA’s cleanup and cost-recovery mechanisms when statutory requirements are met.
The opinion also provides significant guidance on post-Loper Bright statutory review, the APA’s logical-outgrowth doctrine, and the degree of economic precision required when an agency takes an initial regulatory step whose downstream consequences depend on later, site-specific decisions.