The U.S. Environmental Protection Agency proposed on July 1 the sixth Unregulated Contaminant Monitoring Rule (UCMR 6).
Under the Safe Drinking Water Act (SDWA), the UCMR program gathers data about unregulated contaminant occurrences in drinking water. The proposed UCMR 6 would require public water systems (PWSs) to collect national occurrence data for seven ultra-short organofluorine compounds (including certain PFAS), three pesticide metabolites, 13 semi-volatile organic compounds, and seven purgeable organic compounds.
Subject to the availability of appropriations, the EPA will require all community and non-transient non-community water systems (CWSs and NTNCWSs) serving 3300 or more people, and a representative sample of PWSs serving fewer than 3300 people, to conduct monitoring. These contaminants are not currently subject to national primary drinking water regulations (NPDWRs), and the EPA is proposing to require the collection of drinking water occurrence data to inform agency decisions. The data collected will be publicly available.
The EPA is also announcing two public meetings (via webinar) to discuss this proposal of the sixth Unregulated Contaminant Monitoring Rule (UCMR 6).
Eighty percent of community water systems are small groundwater-supplied water systems serving 10,000 or fewer people.
PFAS in the proposed rule include
- Perfluoropropanesulfonic acid (PFPrS)
- Perfluoropropanoic acid (PFPrA)
- Perfluoroethanesulfonic acid (PFEtS)
- Perfluoro-2-methoxyacetic acid (PFMOAA).
The full list of unregulated contaminants is available in the proposed rule and its preamble.
Comments must be received on or before August 31. Click here to read the proposed rule.