Understanding How EPA Develops a New Drinking Water Regulation (Text only)

EPA works to ensure that drinking water is safe by developing National Primary Drinking Water Regulations (NPDWRs) for new contaminants under the Safe Drinking Water Act. Below demonstrates the steps EPA takes when developing new drinking water regulations:

Step 1: Identification

• Identify unregulated contaminants
• Publish a list of unregulated contaminants in a Contaminant Candidate List (CCL)
• Prioritize the contaminants using monitoring data, risk assessments and other relevant information

Step 2: Evaluation

EPA then makes a decision on whether they should start the rulemaking process to develop a national primary drinking water regulation (NPDWR) for a specific contaminant based on three criteria:

1. Health Risk. The contaminant may have an adverse effect on a person’s health.
2. High Occurrence. The contaminant is known to occur or there is a high chance that the contaminant will occur in public water systems often enough and at levels of public health concern.
3. Reduction of Risk.  In the sole judgment of the Administrator, regulation of the contaminant presents a meaningful opportunity for health risk reductions served by public water systems.

Then EPA: 

• Publishes a preliminary regulatory determination report in the Federal Register.
• Allows the public to comment and consults with states and other federal agencies.
• Reviews and considers comments and recommendations.
• Publishes a final notice in the Federal Register.

Step 3. Regulation

Yes to Regulating the Contaminant: Start the rulemaking process to establish the NPDWR.  EPA  also reviews all NPDWRs every six years to determine whether changes are needed. 

No to Regulating the Contaminant:  May develop a health advisory, as appropriate, or take no additional action