Group A Public Water Supplies - PFAS - Current Rulemakings


Chapter 246-290 WAC sets rules for large public water systems. These rules ensure public water systems are safe and reliable to protect public health. The EPA just announced new standards that affect the rule. The Board is exploring how to align with the federal standard and keep drinking water safe.

For More Information

Statutory Authority: RCW 43.20.050, RCW 70A.125, and RCW 70A.130
State Board of Health Contact:  Shay Bauman

Department of Health Contacts: Kseniya Efremova,, and 
Mike Means,

Additional Background

On April 10, 2024, the U.S. Environmental Protection Agency (EPA) published the first national standards related to per- and polyfluoroalkyl substances (PFAS) in drinking water. The EPA officially adopted the standards on June 24, 2024.

The federal standards affect the Board’s Group A Public Water Supplies rule, chapter 246-290 WAC. The Board adopted state action levels and other requirements for PFAS in drinking water in 2021. These rules include criteria that would apply when the EPA adopts a federal maximum contaminant level (MCL) that has a state action level (SAL) set in rule. This provision states that when the EPA adopts MCLs, those MCLs and their requirements, including for monitoring and public notice, replace what rule establishes for SALs.

The EPA adopted the rule on June 24, 2024, but the MCLs do not take effect until April 2029. This would mean that the current protections provided under the SALs would go away until 2029. This includes the requirement that water companies notify customers of dangerous detections of PFAS within 30-days of the detection. To prevent this and preserve public health, the Board adopted an emergency amendment to the rule on June 12, 2024. This amendment clarifies that the MCLs and associated requirements would replace the SALs when the MCLs are effective, instead of when they are adopted. The amendment takes effect June 24, 2024, and stays in effect for 120 days. The Board will consider additional filings to keep the change until the protections are permanent in rule.

In addition to the emergency amendment, the Board initiated rulemakings to adopt the federal standards and relative effective dates into rule, and to explore adopting more stringent PFAS standards before the federal MCLs take effect.

Emergency Rulemaking

Adopted Rule (English)
Adopted Rule (Spanish)

Related Links

June 12, 2024, Board Meeting