Water sector weighs in on legal challenge to EPA PFAS rule

The American Water Works Association (AWWA) and the Association of Metropolitan Water Agencies (AMWA) are urging the D.C. Circuit Court to send EPA’s PFAS drinking water rule back to the agency for further consideration — but without vacating the regulation.

In a reply brief filed in No. 24-1188, the utility groups argue that while they support regulating PFAS under the Safe Drinking Water Act, EPA’s final National Primary Drinking Water Regulation contains legal and technical flaws that warrant reconsideration. Specifically, the associations challenge aspects of EPA’s Maximum Contaminant Level Goals (MCLGs), feasibility determinations, and the agency’s interpretation of statutory requirements when setting enforceable limits for PFOA and PFOS and adopting a hazard index approach for additional PFAS.

However, AWWA and AMWA stop short of seeking to strike down the rule outright. Instead, they request a remand without vacatur, emphasizing that utilities across the country are already moving forward with compliance planning, pilot testing, design work, and financing for treatment upgrades. Vacating the rule, they contend, would create regulatory whiplash, undermine long-term capital planning, and disrupt access to state revolving fund financing and other funding mechanisms tied to federal standards.

By seeking a remand rather than invalidation, the associations frame their position as balancing legal concerns with practical implementation realities. The Court’s handling of the case could determine whether EPA revisits key elements of the PFAS rule — and whether utilities continue compliance efforts under the current regulatory framework while that review proceeds.