Per- and Polyfluoroalkyl Substances (PFAS) Rule

EPA released the final drinking water regulation for six PFAS on April 10, 2024. The rule establishes individual maximum contaminant levels (MCLs) for five PFAS and a hazard index MCL for a mixture of four PFAS. Oregon has two years to adopt the regulations.

Compound	Final MCLG	Final MCL (enforceable levels)
PFOA	Zero	4.0 parts per trillion (ppt) (also expressed as ng/L)
PFOS	Zero	4.0 ppt
PFHxS	10 ppt	10 ppt
PFNA	10 ppt	10 ppt
HFPO-DA (commonly known as GenX chemicals)	10 ppt	10 ppt
Mixtures containing two or more PFHxS, PFNA, HFPO-DA, and PFBS	1 (unitless) Hazard Index	1 (unitless) Hazard Index

EPA’s rule includes routine monitoring of all Community (C) and Non-Transient Non-Community (NTNC) public water systems that must be completed by 2027. EPA's rule would also allow OHA to require action by 2029 at Oregon public water systems where PFAS exceed an MCL.

For more information on the the new PFAS rule, see EPA’s website.

Labs for PFAS Analysis in Drinking Water

Public water systems that are interested in testing for PFAS in their drinking water should use a lab that is accredited by the Oregon Environmental Laboratory Accreditation Program (ORELAP) and analyze the sample using EPA method 533 or 537.1 Version 2. See below for a list of ORELAP-accredited labs for the analysis of PFAS in drinking water:

List of ORELAP-Accredited Labs for PFAS Analysis in Drinking Water