National Drinking Water Regulation for PFAS

A new, legally enforceable drinking water regulation of per-and polyfluoroalkyl substances (PFAS), also known as forever chemicals, has been mandated. The rule sets an enforceable Maximum Contaminant Level at 4 parts per trillion for PFOA and PFOS, the two most studied of the PFAS chemical class. The new regulation also sets an enforceable Maximum Contaminant Level at 10 parts per trillion for 4 other PFAS chemicals and creates an enforceable Hazard Index for 4 additional PFAS chemicals when they are found together in mixtures.

This final rule will be effective 60 days after publication in the Federal Register, which is expected in the coming weeks. Water systems have three years to complete the initial monitoring that is required (by 2027). The new regulation also requires local governments and water utilities to inform the public of the measured levels of PFAS in their drinking water beginning in 2027. Water systems have five years to implement solutions to reduce PFAS in their drinking water if they exceed the levels (by 2029). EPA estimates that approximately 4,000-7,000 (of the 66,000) public drinking water systems will have to take action to reduce PFAS to meet these new standards.

EPA has a number of resources on its website include fact sheets, a Q&A doc, a tool kit on communicating and educating the public, and a guide on which at-home filters can help reduce PFAS in drinking water.

Additionally, EPA held three informational webinars for communities, water systems, and other drinking water professionals about the final regulation.

Webinar recordings and materials:

Leandra Lipson
Author: Leandra Lipson