Why EPA Chose Not to Repeal the PFAS Drinking Water Rule (and What That Really Means)

Per- and polyfluoroalkyl substances—PFAS, the so-called “forever chemicals”—have been under the regulatory microscope for years. PFAS stands for per- and polyfluoroalkyl substances. These are a large class of human-made chemicals that are resistant to water, oil, and heat. They are persistent in the environment and in human bodies (hence the nickname “forever chemicals”). In April 2024, EPA finalized the first nationwide drinking-water standards for several PFAS under the Safe Drinking Water Act (SDWA). In 2025, the agency—now under new leadership—floated rollbacks for parts of that package, including plans to rescind standards for certain newer PFAS and to extend deadlines for compliance. But amid those changes, EPA made a consequential decision: it would not repeal the core rule for the two most notorious PFAS, PFOA and PFOS. Instead, the agency affirmed that the enforceable Maximum Contaminant Levels (MCLs) for PFOA and PFOS would remain in place, while offering more time and flexibility for systems to comply. 

Below, I break down why EPA took this “hold the line” approach—and what it means for utilities, ratepayers, and communities.

The science for PFOA and PFOS is overwhelming.

EPA’s initial 2024 rule rested on a deep evidence base linking PFOA and PFOS to cancer, immune suppression, cholesterol dysregulation, and other adverse health effects at very low concentrations. Rolling back PFOA/PFOS standards outright would have been at odds with a record that EPA itself assembled over multiple administrations. Keeping the MCLs for these legacy PFAS avoids contradicting that record and preserves protections for the chemicals most consistently associated with serious health harms. EPA’s 2025 press statement explicitly framed the decision as “upholding nationwide standards to protect Americans from PFOA and PFOS,” underscoring that public-health imperative.

Legal defensibility matters (a lot).

Under the SDWA, EPA must base standards on the best available science and demonstrate that benefits justify costs to the extent feasible. Because the docket for PFOA and PFOS is robust, scrapping their MCLs would invite immediate litigation from states and NGOs arguing the agency was abandoning a defensible rule without a scientific or statutory basis. By keeping those MCLs—but reconsidering newer substances (PFHxS, PFNA, GenX/HFPO-DA, and the hazard-index mixture) and stretching timelines—EPA reduces its litigation exposure while still showing responsiveness to feasibility concerns. EPA has already signaled it will defend the PFOA/PFOS standards in court, even as it proposes compliance extensions. 

Implementation challenges are real—so EPA opted for flexibility, not repeal.

Water systems—especially small and rural ones—must pilot treatment options, secure funding, design and build facilities, and hire and train operators. EPA acknowledged these realities by announcing it would propose a two-year extension of the compliance date (from 2029 to 2031) and launch a PFAS outreach initiative to connect utilities with technical assistance and financing (e.g., Drinking Water SRF, WIFIA). That approach addresses the practical crunch without sacrificing the protective standards themselves. Trade and state associations representing small systems praised the delay as “reasonable and flexible,” a political signal that flexibility can calm implementation headwinds better than repeal. 

A targeted rollback elsewhere bought room to keep the core intact

In the same breath that EPA preserved PFOA/PFOS limits, it announced plans to rescind and reconsider standards for other PFAS (PFHxS, PFNA, GenX, and the hazard-index mixture). That targeted retreat helped the agency balance competing pressures: it addressed industry and utility critiques that some elements of the 2024 rule overreached or were too costly to implement on the same timeline, while signaling to health advocates and states that the most consequential protections would stand. Legal and trade press uniformly described this as a partial rollback that left the PFOA/PFOS MCLs in place but reopened the rest. 

“Polluter pays” politics and practicalities.

EPA’s statement emphasized that public water systems are passive receivers: they don’t create PFAS; they inherit them from upstream dischargers and legacy contamination. Keeping the PFOA/PFOS rule tight gives EPA a stronger hand to push upstream controls (like effluent guidelines) and to pursue enforcement or settlements that shift costs from ratepayers to polluters. Politically, that’s easier to defend than making utilities—and their customers—shoulder the burden without a clear federal standard that anchors liability and cleanup expectations. 

National consistency and state momentum.

Many states have already moved the lever on PFAS controls. Thus, eliminating the rule would cause inconsistency between states.