United States Government Publishing Office publisher pbl distributor dst United States National Archives and Records Administration Office of the Federal Register author aut Government Organization text government publication eng FR Regulatory Information 2026_register executive 2026-07-01 article Proposed Rules D09002ee1e4125b5f D09002ee1e4125be1 United States Environmental Protection Agency originator org United States Government Agency or Subagency The U.S. Environmental Protection Agency (EPA or agency) is proposing the sixth Unregulated Contaminant Monitoring Rule (UCMR 6). Under the Safe Drinking Water Act (SDWA), the UCMR program gathers data about unregulated contaminant occurrence in drinking water. The proposed UCMR 6 would require public water systems (PWSs) to collect national occurrence data for seven ultrashort organofluorine compounds (including certain PFAS), three pesticide metabolites, 13 semivolatile 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 3,300 or more people, and a representative sample of PWSs serving fewer than 3,300 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). 91 FR 39952 https://www.govinfo.gov/app/details/FR-2026-07-01/2026-13263 2026-13263 fr01jy26-21 RIN 2040-AG33 6560-50-P EPA-HQ-OW-2023-0469 FRL-10857-03-OW https://www.govinfo.gov/app/details/FR-2026-07-01/2026-13263 https://www.govinfo.gov/content/pkg/FR-2026-07-01/html/2026-13263.htm https://www.govinfo.gov/content/pkg/FR-2026-07-01/pdf/2026-13263.pdf 22 p. 39952 39973 91 FR 39952 Title 40 Part 141 40 CFR Part 141 RIN 2040-AG33 Revisions To Establish the Sixth Unregulated Contaminant Monitoring Rule (UCMR 6) for Public Water Systems; Federal Register Vol. 91, Issue PRORULE 2026-13263 ENVIRONMENTAL PROTECTION AGENCY 2026-07-31 2026-08-31 EPA-HQ-OW-2023-0469 FRL-10857-03-OW 6560-50-P 2026-13263 Proposed rule; notice of public meeting.

The U.S. Environmental Protection Agency (EPA or agency) is proposing the sixth Unregulated Contaminant Monitoring Rule (UCMR 6). Under the Safe Drinking Water Act (SDWA), the UCMR program gathers data about unregulated contaminant occurrence in drinking water. The proposed UCMR 6 would require public water systems (PWSs) to collect national occurrence data for seven ultrashort organofluorine compounds (including certain PFAS), three pesticide metabolites, 13 semivolatile 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 3,300 or more people, and a representative sample of PWSs serving fewer than 3,300 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).

Comments must be received on or before August 31, 2026. Comments on the information collection provisions of the proposed rule under the Paperwork Reduction Act (PRA) must be received by the Office of Management and Budget's Office of Information and Regulatory Affairs (OMB-OIRA) on or before July 31, 2026. Please refer to the PRA section under "Statutory and Executive Order Reviews" in this preamble for specific instructions. Public meeting: the EPA will hold two identical virtual, public meetings on August 11, 2026 and August 12, 2026 at https://www.epa.gov/dwucmr/unregulated-contaminant-monitoring-rule- ucmr-meetings-and-materials. Please refer to the SUPPLEMENTARY INFORMATION section for additional information on the public meetings. Brenda Bowden, Standards and Risk Management Division (SRMD), Office of Ground Water and Drinking Water (OGWDW) (MS 140), Environmental Protection Agency, 26 West Martin Luther King Drive, Cincinnati, Ohio 45268; telephone number: 513-569- Vol. 91, no. 125 Office of the Federal Register, National Archives and Records Administration 2026-07-01 continuing daily deposited born digital 517 p. Table of Contents: AE 2.7: GS 4.107: AE 2.106: KF70.A2 https://www.govinfo.gov/app/details/FR-2026-07-01 P0b002ee1e40feaa8 0097-6326 0042-1219 0364-1406 769-004-00000-9 000582072 f:fr01jy26 https://www.govinfo.gov/app/details/FR-2026-07-01 https://www.govinfo.gov/content/pkg/FR-2026-07-01/pdf/FR-2026-07-01.pdf https://www.govinfo.gov/content/pkg/FR-2026-07-01/xml/FR-2026-07-01.xml fdlp 39843 40351 DGPO 2026-07-01 2026-07-01 FR-2026-07-01 machine generated eng FR FR-2026-07-01 91 125