Radionuclides in Drinking Water Rule
In 2000, EPA revised the radionuclides regulation, which had been in effect since 1977. The revisions required new monitoring provisions to ensure that all customers of community water systems will receive water that meets the Maximum Contaminant Levels for radionuclides in drinking water. EPA also issued a standard for uranium, as required by the 1986 amendments to the Safe Drinking Water Act. The current standards are: combined radium 226/228 of 5 pCi/L; a gross alpha standard for all alphas of 15 pCi/L (not including radon and uranium); a combined standard of 4 mrem/year for beta emitters. The new MCL for uranium is 30 µg/L.
- Radionuclides final rule (December 7, 2000)
- Fact Sheet on Final Rule
- Quick Reference Guide for the Radionuclides Rule (PDF 2 pp, 107 K) (About PDF)
- National Primary Drinking Water Regulations - Code of Federal Regulations 40 CFR Part 141
In 2004, EPA issued a final rule with three additional analytical methods that use inductively coupled plasma mass spectrometry (ICP-MS) technology for compliance determinations of Uranium in drinking water.
- August 25, 2005, Federal Register Notice
In 2004, EPA published minor corrections to the Radionuclides Rule to identify a detection limit for uranium and to clarify text in the rule.
- June 29, 2004 - National Primary Drinking Water Regulations: Minor Corrections and Clarification to Drinking Water Regulations; National Primary Drinking Water Regulations for Lead and Copper
In 2000, EPA published a Notice of Data Availability (NODA) to update the public and the regulated community with new information that had become available since the 1991 proposal. The Agency also developed a Technical Support Document, which provides background information and further describes the analyses discussed in the NODA, and the preliminary Health Risk Reduction and Cost Analysis, which presents the analyses of projected impacts, costs, risk reductions, and benefits for the uranium NPDWR and the new monitoring requirement for radium-228.
- Notice of Data Availability – April 21, 2000
- Technical Support Document (PDF 164 pp, 505 K) (About PDF)
- Preliminary HRCCA (PDF 183 pp, 743 K) (About PDF)
In 1997, EPA held a public meeting to discuss regulatory issues associated with the 1991 Radionuclides Rule proposal.
In 1991, EPA proposed revisions to the July 9, 1976 rule. The final rule published in 2000 finalized this 1991 proposal.
- 1991 Proposal (July 18, 1991) - 56 Federal Register 33050