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Drinking Water Contaminant Candidate List (CCL) and Regulatory Determination

  • Regulatory Determination 4

    January 19, 2021 - EPA announced final regulatory determinations for eight contaminants listed on the fourth Contaminant Candidate List, including PFOA and PFOS. Read more.

  • EPA evaluates substances that may be in your drinking water by developing Contaminant Candidate Lists and periodically issuing a Regulatory Determination. Learn about the CCL and Regulatory Determination.

About the Drinking Water CCL

Drinking Water Reservior
The Contaminant Candidate List (CCL) is a list of drinking water contaminants that are known or anticipated to occur in public water systems and are not currently subject to EPA drinking water regulations.
  • Basic information about the CCL
  • What EPA does with the CCL

Current and Previous CCLs

Lists
Read about the most recent and prior CCLs.
  • Draft CCL 5
  • CCL 4 (2016)
  • CCL 3 (2009)
  • CCL 2 (2005)
  • CCL 1 (1998)

What is a Contaminant?

Drinking water contaminants
  • Definition of "contaminant"
  • Types of drinking water contaminants

Regulatory Determination

gavel
The Safe Drinking Water Act requires EPA to periodically decide whether or not to regulate at least five contaminants on the contaminant candidate list. This action is called regulatory determination.
  • Basic information about Regulatory Determination
  • Regulatory Determination 4
  • Regulatory Determination 3
  • Regulatory Determination 2
  • Regulatory Determination 1
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on July 29, 2021
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