Association of California Water Agencies
EPARulemakingEPA-HQ-OW-2023-0469

Revisions to Establish the Sixth Unregulated Contaminant Monitoring Rule (UCMR 6) for Public Water Systems

RIN
2040-AG33
Last modified
Sep 4, 2026
Comment window
closed 20d ago
Association of California Water Agencies filings
1

Activity

Association of California Water Agencies filed 1 comment on this docket between Sep 1, 2026 and Sep 1, 2026. 24 other organizations filed here. The comment window closed 20d ago.

What Association of California Water Agencies filed (1)

Sep 1, 2026· Comment submitted by Association of California Water Agencies (ACWA)· EPA-HQ-OW-2023-0469-0243

Filed on regulations.gov — full text not in the inline record.

Abstract

The Safe Drinking Water Act (SDWA), as amended in 1996, requires that the EPA establish a program to monitor up to 30 unregulated contaminants every five years. EPA published the rule defining the fifth cycle of monitoring (UCMR 5) on December 27, 2021 (86 FR 73131). This action meets the SDWA requirement by establishing the terms for the next (sixth) cycle of monitoring and identifying the new unregulated contaminants to be monitored during the five-year UCMR 6 period of 2027-2031. Monitoring preparations are anticipated in 2027, with sample collection between 2028-2030 and reporting concluding in 2031. Related Docket: EPA-HQ-OW-2020-0530

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