EPA has drinking water regulations for more than 90 contaminants. The Safe Drinking Water Act (SDWA) requires EPA to list unregulated contaminants which are known or anticipated to occur in public water systems and which may require a national drinking water regulation in the future. Every five years, EPA must publish a list of contaminants called the Contaminant Candidate List (CCL). After publishing, EPA must also decide whether to regulate at least five contaminants from the list (called Regulatory Determinations). EPA uses the CCL to prioritize research and data collection efforts to inform the Agency's decision on whether we should regulate a specific contaminant.
In September 2009, EPA published the final version of the third Drinking Water Contaminant Candidate List (CCL 3).
In February 2008, EPA announced the draft third Drinking Water Contaminant Candidate List (CCL 3) and described the process and rationale used to develop the list.
The links below provide more information about Contaminant Candidate Lists and Regulatory Determinations.
- Basic Information - This page answers questions about how the CCL is developed, how it fits into the regulatory development process and links to data and information on CCL contaminants.
- CCL 3 List - This page describes the CCL 3 process and provides relevant links to documents and information used to compile the Final CCL 3 List.
- CCL 2 List and Regulatory Determinations - These pages provide the contaminants listed on the second CCL and the CCL 2 Regulatory Determinations.
- CCL 1 List and Regulatory Determinations - These pages provide the contaminants listed on the first CCL and the CCL 1 Regulatory Determinations.
- Related Activities & Dates - This page includes key meetings, Federal Register Notices and dates related to the CCL.