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Contaminant Candidate List (CCL) and Regulatory Determination

Contaminant Candidate List 4-CCL 4

The Contaminant Candidate List (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). EPA announced the Final CCL 4 on November 17, 2016.

Federal Register Notices

What's on the Final CCL 4

The Final CCL 4 includes 97 chemicals or chemical groups and 12 microbial contaminants. The list includes, among others, chemicals used in commerce, pesticides, biological toxins, disinfection byproducts, pharmaceuticals and waterborne pathogens. These lists can be read by selecting the links below.