An official website of the United States government.

We've made some changes to If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Contaminant Candidate List (CCL) and Regulatory Determination

CCL 4 Technical Support Documents

EPA developed several technical support documents it utilized to produce the Final CCL 4. These documents include a: 
  • Summary of nominations received from the public for CCL 4.
  • Listing and description of data sources used to evaluate the nominated contaminants.
  • Description of the process used to screen and evaluate the nominated contaminants for potential inclusion on the Preliminary Contaminant Candidate List.
  • Detailed contaminant information summary sheet for each contaminant on the Final CCL 4.
Read the technical support documents for the Final CCL 4.
You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.