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Contaminant Candidate List (CCL) and Regulatory Determination

Contaminant Candidate List 5 (CCL 5)

EPA is beginning the development of the fifth Contaminant Candidate List (CCL 5). The CCL is a list of contaminants that are currently not subject to any proposed or promulgated national primary drinking water regulations, but are known or anticipated to occur in public water systems. Contaminants listed on the CCL may require future regulation under the Safe Drinking Water Act (SDWA). 

October 4, 2018 - EPA  is requesting nominations of chemicals, microbes, or other materials for consideration on the CCL 5. The public may nominate contaminants by following the instructions contained in the Federal Register notice for CCL 5 nominations. The deadline for nominations is December 4, 2018.