The U.S. Environmental Protection Agency held a public meeting on July 16 in Cincinnati, Ohio, to discuss potential approaches to developing a proposal for the fifth Unregulated Contaminant Monitoring Rule (UCMR 5) for public drinking water systems. The meeting was also broadcast on the web.
The EPA discussed analytical methods and analytes the agency is considering, including per- and polyfluoroalkyl substances (PFAS); sampling design; minimum reporting levels; and other possible requirements. A proposed rule is expected by summer 2020 with a final rule in winter 2021.
The EPA is considering UCMR 5 to be conducted similarly to previous unregulated contaminant monitoring cycles every five years: a stratified random sample of 800 small water systems serving 10,000 or fewer people by ground and surface water source and size and a census of all community water systems serving more than 10,000 people.
The EPA will cover the costs of small water system sample testing. The EPA is considering reducing the sampling points for these systems to reduce burden and cost.
The EPA addressed monitoring of PFAS in more detail. In addition to PFAS compounds monitoring, seven specific PFAS analytes were nominated on the Contaminant Candidate List 5 for consideration in UCMR 5. EPA officials noted that the EPA PFAS Action Plan committed the EPA to monitor for more PFAS compounds in UCMR 5. Relative to the priority for PFAS compounds to be included, EPA officials indicated they would be awaiting input to assist the agency in making decisions on priority for monitoring.
The EPA noted the agency did not have health advisories for many PFAS compounds, but that did not preclude the agency from monitoring them under UCMR 5, which would be useful in developing such advisories.
UCMR 5 monitoring would begin in January 2023 and be completed by 2026.