The Environmental Protection Agency has closed the public comment period on two proposed rules that would materially reshape the federal regulatory framework for per- and polyfluoroalkyl substances (PFAS) in drinking water. The comment period closed on July 20, 2026, following a virtual public hearing conducted on July 7, 2026. Together, these proposals signal a potential recalibration of the current PFAS regime and could have significant implications for public water systems, manufacturers, and other stakeholders navigating PFAS-related compliance and litigation exposure.
The first proposal would rescind the Maximum Contaminant Levels (MCLs) established for PFHxS, PFNA, HFPO-DA (commonly known as GenX), and the hazard index mixture applicable to combinations of those compounds. If finalized, this action would narrow the scope of federal PFAS drinking water regulation to PFOA and PFOS, leaving the four rescinded compounds and their mixture outside the current enforceable federal standard. Stakeholders should recognize that a narrower federal framework does not necessarily reduce exposure at the state level, where independent PFAS standards and enforcement priorities continue to evolve.
The second, companion proposal would extend the compliance deadlines for PFOA and PFOS for qualifying public water systems. Under the proposal, the applicable compliance date would move from April 26, 2029 to April 26, 2031. This additional runway is designed to provide public water systems with greater flexibility for treatment planning, technology evaluation, procurement, and capital deployment associated with meeting the retained PFOA and PFOS standards.
For public water systems, industrial users, and downstream commercial parties, these proposals may influence near-term decisions on capital projects, treatment infrastructure investments, vendor contracts, and disclosure obligations. They may also affect the trajectory of ongoing and anticipated PFAS-related litigation and cost-recovery efforts, particularly where compliance timelines and the scope of regulated substances inform damages theories and remediation planning. Clients should continue to monitor the EPA's next steps, including any final rule issuance, as well as parallel activity by state regulators.
This update is provided for general informational purposes only and does not constitute legal advice. Clients facing PFAS-related regulatory, compliance, or litigation questions should seek tailored advice based on their specific circumstances.