Draft CCL5 Released

On July 12, 2021, the Environmental Protection Agency (EPA) announced the availability of the draft Contaminant Candidate List 5 (CCL5).  A link to a copy of the pre-publication Federal Register notice is here (prepublication_draft_ccl_5_federal_register_notice).  Public comments will be due 60 days after publication in the Federal Register.

From the EPA Press Release: “The Draft CCL5 includes 66 individual chemicals, 12 microbes, and three chemical groups – per- and polyfluoroalkyl substances (PFAS), cyanotoxins, and disinfection byproducts (DBPs). These contaminants have been identified as agency priorities and contaminants of concern for drinking water. PFAS are proposed as a group, with the exception of PFOA and PFOS because the agency is moving forward with national primary drinking water standards for these two contaminants.”

EPA plans to meet with the Science Advisory Board regarding the draft CCL5 during fall 2021, and expects to publish the final CCL5 during the summer of 2022.

EPA Press Release



Within 18 months of enactment of the 1996 Safe Drinking Water Act Amendments, and then every five years thereafter, EPA is required to propose and finalize a 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….”  After publication of the CCL, EPA then goes through a review process (referred to as a Regulatory Determination) and makes an assessment as to whether a drinking water regulation should be promulgated for at least five of the constituents on the CCL.