EPA’s PFAS Water Rule Faces Legal Scrutiny Over Cost Estimates

The Environmental Protection Agency’s efforts to regulate harmful PFAS chemicals in drinking water have come under increased legal and public scrutiny due to concerns about the accuracy of its cost estimates. According to a report released by the U.S. Government Accountability Office (GAO), the EPA followed legal requirements by publishing and soliciting public input on its projected costs. However, the matter remains in court as water utilities and industry groups challenge the financial feasibility of compliance.

The EPA proposed limits in 2023 for six types of per- and polyfluoroalkyl substances—often called “forever chemicals” due to their persistence in the environment—citing health risks such as cancer. Initially, the agency issued a cost-benefit analysis as required by the Safe Drinking Water Act, and after receiving public feedback, it revised its estimate upward in April 2024 to reflect new data and concerns from stakeholders. These revised estimates factored in higher potential expenses for treatment methods, such as the need for additional pilot testing of filtration systems.

While the agency also addressed potential unquantified costs—such as more frequent replacement of treatment media when multiple PFAS are present—it acknowledged significant uncertainty in the overall cost projections. Critics argue that the EPA’s estimates still fall short of capturing the true financial burden on water systems, especially smaller utilities, prompting at least three legal challenges since June 2024. As of late July 2025, the rule remains under litigation, and EPA has announced plans to reconsider portions of the regulation, including rescinding some contaminant limits.

The cost and feasibility of implementing this regulation could have long-term consequences for public water systems and, by extension, ratepayers. If the regulation proceeds as finalized, residents may face higher water bills to cover system upgrades needed to comply with the new standards.

Article by multiple contributors, based upon information from a GAO press release.

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