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Contaminant Candidate List (CCL) and Regulatory Determination

Regulatory Determination 4

The Safe Drinking Water Act (SDWA) directs EPA to publish a list of contaminants (referred to as the Contaminant Candidate List, or CCL) to assist in priority-setting efforts. The SDWA also directs EPA to select no fewer than five contaminants from the current CCL and determine whether to regulate these contaminants with a National Primary Drinking Water Regulation (NPDWR). A regulatory determination is a decision on whether EPA should initiate a rulemaking process to develop an NPDWR for a specific contaminant. Learn more.

Final Regulatory Determinations for CCL 4

On February, 22, 2021, EPA reissued final regulatory determinations for contaminants on the fourth Contaminant Candidate List (CCL 4). EPA is making final determinations to regulate two contaminants, perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), in drinking water and to not regulate six contaminants (i.e., 1,1-dichloroethane, acetochlor, methyl bromide (bromomethane), metolachlor, nitrobenzene, and RDX). With the final Regulatory Determinations for PFOA and PFOS, EPA will move forward to implement the national primary drinking water regulation development process for these two PFAS. The Regulatory Determinations also outline avenues that the agency is considering to further evaluate additional PFAS chemicals and provide flexibility for the agency to consider groups of PFAS as supported by the best available science.

Supporting Materials 

Preliminary Regulatory Determinations for CCL 4

On February 20, 2020, EPA announced and requested public comment on the preliminary regulatory determinations for eight CCL 4 contaminants. EPA made preliminary determinations to regulate PFOS and PFOA in drinking water and to not regulate six contaminants (i.e., 1,1-dichloroethane, acetochlor, methyl bromide (bromomethane), metolachlor, nitrobenzene, and RDX).

Supporting Materials