Rescission of Regulatory Determinations and Removal of Related Provisions for Four PFAS Substances (PFHxS, PFNA, HFPO-DA (GenX), and the Mixture of These Three PFAS Plus PFBS)

What it does

The Environmental Protection Agency (EPA) is proposing to rescind its regulatory determinations to regulate four per- and polyfluoroalkyl substances (PFAS)--perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), hexafluoropropylene oxide dimer acid and its ammonium salt (HFPO-DA, commonly known as GenX chemicals), and mixtures of these three PFAS plus perfluorobutane sulfonic acid (PFBS)--under the Safe Drinking Water Act (SDWA). The EPA is also proposing to rescind all associated regulatory provisions currently codified in the EPA's 2024 PFAS National Primary Drinking Water Regulations (NPDWR) exclusive to these PFAS that were promulgated pursuant to the regulatory determinations that the EPA is now proposing to rescind, including the final Maximum Contaminant Levels (MCLs) that would have required monitoring, and where necessary, treatment by public water systems (PWSs). This proposed action is necessary to correct the unlawful procedure under which these regulations were promulgated. Under the EPA's prior interpretation, the EPA proposed and finalized regulatory determinations and regulations for these PFAS simultaneously and in tandem. Under the best reading of the statute, the EPA is not authorized to take such actions simultaneously and therefore, the Agency proposes to rescind those regulatory determinations, Maximum Contaminant Level Goals (MCLGs) and associated portions of the 2024 PFAS NPDWR. The EPA is seeking public comment on this proposal.

The Environmental Protection Agency's summary, as published in the Federal Register.

What it would change

2 parts of Title 40 of the Code of Federal Regulations:

40 CFR 141, 40 CFR 142

Before this

No earlier Federal Register document under regulation identifier 2040-AG53 since Jan. 1, 2025.

What happens next and when

Comments must be received on or before July 20, 2026.

The agency's dates, word for word.

Check it yourself

• The document in the Federal Register
• Docket EPA-HQ-OW-2025-0654 on Regulations.gov
• Title 40 on eCFR

The record as published

Source: the Federal Register (public domain). The document in the Federal Register