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  2. Contaminant Candidate List (CCL) and Regulatory Determination

Regulatory Determination 3

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. SDWA also directs the Agency to select five or more contaminants from the current CCL and determine whether to regulate these contaminants with a National Primary Drinking Water Regulation (NPDWR).
 
To regulate a contaminant SDWA requires that EPA determine whether:
  1. The contaminant may have an adverse effect on the health of persons;
  2. The contaminant is known to occur or there is a substantial likelihood the contaminant will occur in public water systems with a frequency and at levels of public health concern; and
  3. In the sole judgment of the Administrator, regulation of the contaminant presents a meaningful opportunity for health risk reductions for persons served by public water systems.

Final Regulatory Determinations for CCL 3

On January 4, 2016, EPA announced the final determinations not to regulate four contaminants on the Third Contaminant Candidate List (CCL 3) – dimethoate, 1,3-dinitrobenzene, terbufos, and terbufos sulfone. The agency delayed the final regulatory determination on strontium to consider additional data and decide whether there is a meaningful opportunity for health risk reduction by regulating strontium in drinking water.

  • Federal Register Notice: Announcement of Final Regulatory Determinations for the Third Drinking Water Contaminant Candidate List
  • Other support documents for the final regulatory determinations can be found at www.regulations.gov under Docket ID EPA-HQ-OW-2012-0155

Preliminary Regulatory Determinations for CCL 3

EPA announced and requested public comment on the preliminary regulatory determinations for five CCL 3 contaminants. EPA made preliminary determinations to regulate strontium in drinking water and to not regulate four contaminants (i.e., dimethoate, 1,3-dinitrobenzene, terbufos, and terbufos sulfone).
 
  • Federal Register Notice: Announcement of Preliminary Regulatory Determinations for the Third Drinking Water Contaminant Candidate List
  • Technical support documents for the preliminary regulatory determinations can be found at Regulations.gov using docket ID EPA-HQ-OW-2012-0155
  • Fact Sheet: Preliminary Regulatory Determinations for the Third Drinking Water Contaminant Candidate List

Public Meetings Held On Preliminary Regulatory Determinations for the CCL3

EPA hosted a public stakeholder meeting on December 9, 2014, in Washington, DC, to discuss the Agency’s Regulatory Determination 3. For more information see the slides presented.

  • Slides Presented at the December 9th Public Meeting on Preliminary Regulatory Determinations for the CCL3
  • EPA hosted a public stakeholder meeting on June 16, 2011, in Washington, DC, to discuss the Agency’s Regulatory Determination 3. For more information see the slides presented.
    • Slides Presented at the June 16th Public Meeting on Preliminary Regulatory Determinations for the CCL3

Contaminant Candidate List (CCL) and Regulatory Determination

  • Basic Information
  • Draft Contaminant Candidate List 6
  • Contaminant Candidate List 5
  • Contaminant Candidate List 4
  • Contaminant Candidate List 3
  • Contaminant Candidate List 2
  • Contaminant Candidate List 1
  • Regulatory Determination 5
  • Regulatory Determination 4
  • Regulatory Determination 3
  • Regulatory Determination 2
  • Regulatory Determination 1
  • Types of Drinking Water Contaminants
Contact Us About the CCL and Regulatory Determinations
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on February 11, 2025
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