Proposed MCLGs and MCLs for PFAS

Read the full post from TRC.

On March 3, 2021, the Environmental Protection Agency (EPA) published a Final Regulatory Determination for Contaminants on the Fourth Drinking Water Contaminant Candidate List (86 FR 12272). There were 109 contaminants on the Fourth Contaminant Candidate List, and of those, EPA made final regulatory determinations for eight of those contaminants. Of those eight, only two, perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), were determined to warrant further regulation following the process in the Safe Drinking Water Act (SDWA). Statutory criteria for pursuing a National Primary Drinking Water Regulation (NPDWR) are as follows:

(a) The contaminant may have an adverse effect on the health of persons;

(b) The contaminant is known to occur or there is a substantial likelihood that the contaminant will occur in public water systems with a frequency and at levels of public health concern; and

(c) In the sole judgment of the Administrator, regulation of such contaminant presents a meaningful opportunity for health risk reduction for persons served by public water systems.

After making the determination that the three criteria apply, as the EPA did for PFOS and PFOA², the EPA was required to propose a regulation within 24 months, by March 3, 2023, and take action on a final regulation within 18 months of the proposal.