The Environmental Protection Agency (EPA) posted a pre-publication version of a final Regulatory Determination for eight contaminants that were listed on the fourth Contaminant Candidate List (CCL4). The final Regulatory Determination was signed by the EPA Administrator on January 15, 2021 and was submitted to the government printing office for publication in the Federal Register.
In the final Regulatory Determination EPA will proceed to regulate two PFAS: perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA).
Once the final Regulatory Determination is published in the Federal Register EPA has 24 months to publish for public comment proposed Maximum Contaminant Level Goals (MCLG) and MCLs for PFOA and PFOS. Following that deadline, EPA has 18 months to publish final MCLGs and MCLs.
As part of the final Regulatory Determination, EPA will not regulate 1,1-dichloroethane, acetochlor, methyl bromide (bromomethane), metolachlor, nitrobenzene, and RDX.
Copy of the pre-publication Federal Register notice is here (Fed Reg_ccl_reg_det_4.final_web ).
Under the Safe Drinking Water Act (SDWA) Amendments of 1996, every five years EPA is to make a Regulatory Determination (a decision whether or not to proceed with developing a drinking water regulation) for at least five constituents from the CCL. Constituents are included on the CCL that “…are not subject to any proposed or promulgated national primary drinking water regulation, which are known or anticipated to occur in public water systems, and which may require regulation….” The CCL4 was published in November 2016. In February 2020 EPA published the proposed Regulatory Determination for constituents on the CCL4 for public comment.