CERCLA and PFAS Superfund Designations
The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) — commonly known as Superfund — provides EPA authority to compel cleanup of contaminated sites and recover costs from responsible parties. In 2024, EPA designated PFOA and PFOS as CERCLA hazardous substances, a pivotal decision that enables Superfund enforcement actions for PFAS contamination. This designation subjects parties responsible for PFAS releases to potentially significant cleanup liability and creates a formal mechanism for EPA-led site cleanup at PFAS-contaminated sites where responsible parties cannot or will not remediate.
Risk-Based Prioritization
Contaminated site cleanup prioritization uses risk assessment frameworks that consider PFAS concentration, proximity to water supplies, population served by affected water sources, and available exposure pathways. Sites with direct impact on drinking water — particularly those affecting public water supplies serving large populations — receive the highest prioritization. The National Priorities List (NPL) under CERCLA provides formal site ranking, and PFAS-contaminated military sites have been among the most prominent recent additions to the NPL.
Responsible Party Liability
CERCLA’s strict, joint and several liability framework means that any party that contributed to PFAS contamination at a site can be held responsible for the full cleanup cost, regardless of the proportion of their contribution. This broad liability exposure has driven cleanup engagement by PFAS manufacturers and users who might otherwise defer remediation. The CERCLA hazardous substance designation for PFAS opens liability claims against PFAS manufacturers and users at previously unregulated sites.
Interim Remedial Measures
While long-term site cleanup plans are developed and implemented, EPA and state agencies often require interim remedial measures to protect drinking water at contaminated sites. These typically include providing alternative water supplies — bottled water delivery or connection to uncontaminated water systems — to affected residents, installation of point-of-entry treatment at affected homes, or accelerated treatment system installation at affected water utilities. These interim measures address immediate public health needs while long-term remediation planning proceeds.