In the latest federal action on PFAS, the EPA published announcement of final regulatory determinations for eight contaminants on the fourth drinking water Contaminant Candidate List. The determinations are effective March 3, 2021. The final regulatory determinations for eight of the 109 contaminants listed on the Fourth Contaminant Candidate List are:

• Regulate: perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA).
• Not Regulate: 1,1-dichloroethane, acetochlor, methyl bromide (bromomethane), metolachlor, nitrobenzene, and RDX.

This regulatory determination means that the EPA will begin the process to propose and promulgate a national primary drinking water regulation (MCL) for PFOS and PFOA.

“The latest EPA PFAS actions add PFOS and PFOA to national primary drinking water regulation. We are closely monitoring that process.”

Kelly Collins, Managing Principal, Geology/Hydrogeology