On May 14, 2025, the US Environmental Protection Agency (EPA), under Administrator Lee Zeldin, announced its decision to retain the national enforceable drinking water standards for two of the most scrutinized per- and polyfluoroalkyl substances (PFAS): perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). This move maintains the Maximum Contaminant Levels (MCLs) promulgated by the Biden Administration in April 2024, which marked the first legally binding federal drinking water limits for individual PFAS chemicals. At the same time, the EPA signaled a shift in direction with respect to other PFAS regulations, announcing its intent to rescind and reconsider the regulatory determinations for PFHxS, PFNA, HFPO-DA (commonly known as GenX) and PFBS—chemicals previously subject to regulation under a cumulative hazard index.
This regulatory pivot reflects a nuanced recalibration of the federal government’s PFAS strategy by balancing ongoing public health protections with concerns about the feasibility of implementation, particularly for rural and small community water systems. In this context, the EPA’s decision has significant implications for three distinct constituencies: passive receivers, such as drinking water utilities; upstream chemical manufacturers and industrial dischargers; and communities facing long-term exposure to PFAS.
Most notably, the EPA’s reaffirmation of the PFOA and PFOS MCLs preserves a major element of the Biden-era regulatory framework. These limits remain enforceable nationwide. Administrator Zeldin’s statement that “we are on a path to uphold the agency’s nationwide standards” underscores the EPA’s ongoing commitment to protecting public health from legacy PFAS contamination. This stability is welcome news for affected communities and environmental advocates who feared a wholesale rollback of PFAS rules.
At the same time, the agency’s decision to extend compliance deadlines and provide regulatory “flexibility” acknowledges the considerable burdens faced by public water systems tasked with implementing these rules. The original compliance deadline of 2029 was already considered ambitious. Many utilities, especially smaller systems lacking technical and financial capacity, have struggled with pilot testing, engineering design, and capital planning necessary to bring PFAS concentrations into compliance. EPA’s new proposal to extend the deadline to 2031 and offer tailored assistance through the newly launched PFAS OUTreach Initiative reflects a pragmatic response to these concerns. As stated by the Association of State Drinking Water Administrators, the extension “will address the number of systems that would be out of compliance in 2029 due to not being able [to] complete all of these tasks on time.”
From a legal and policy standpoint, the most consequential rollback involves the hazard index regulation for PFHxS, PFNA, GenX and PFBS. The hazard index approach—developed under the Biden Administration—allowed EPA to regulate the cumulative risk of multiple PFAS with similar health endpoints. Its rescission will likely reduce near-term compliance burdens for utilities and industrial facilities. However, it also raises questions about EPA’s authority to regulate PFAS mixtures under the Safe Drinking Water Act and the scientific sufficiency of the remaining chemical-by-chemical framework. Zeldin’s EPA justified the rollback as necessary to ensure adherence to statutory procedures, but environmental groups will likely challenge the reversal as being too restrictive.
For manufacturers, this new regulatory posture carries mixed consequences. On the one hand, the rescission of additional MCLs and the delay in compliance timelines may reduce litigation exposure and capital outlays in the short term. On the other, EPA’s continued emphasis on holding polluters accountable—coupled with its coordination with the Department of Justice—signals that enforcement actions will remain a central part of the federal PFAS strategy. Zeldin’s invocation of the “polluter pays” principle suggests future rulemakings may seek to clarify the scope of liability for upstream contributors, particularly in CERCLA and Clean Water Act contexts.
EPA’s May 2025 announcement reveals a strategic recalibration, not abandonment, of PFAS regulation. It preserves core health protections while attempting to mitigate the real-world challenges of compliance and implementation. For passive receivers, the path forward remains arduous but better defined; for industry, the regulatory risks have shifted but not disappeared. Ultimately, the broader PFAS policy framework is still evolving—and this moment represents a critical inflection point in balancing environmental integrity, administrative feasibility, and legal defensibility.
