EPA published the proposed fifth Unregulated Contaminant Monitoring Rule (UCMR 5) in the Federal Register.
In the proposed rule, UCMR 5 would require sample collection for 29 per- and polyfluoroalkyl substances (PFAS) and lithium between 2023 and 2025. This sampling would use analytical methods developed by EPA and consensus organizations, according to the proposed rule.
The analytical methods, according to the proposed rule, include: monitoring time frame; sampling locations; data elements; data reporting timeframes; and conforming and editorial changes, such as those necessary to remove requirements solely related to UCMR 4.
In accordance with America's Water Infrastructure Act (AWIA), the UCMR 5 program will continue to include public water system (PWS) monitoring for utilities serving a population larger than 10,000 people. Additionally, all PWSs serving between 3,300 and 10,000 people must monitor for the contaminants in a particular UCMR cycle and only a nationally representative sample of PWSs serving fewer than 3,300 people are required to monitor for those contaminants.
The UCMR 5 proposal fulfills a key goal of the EPAs 2019 PFAS Action Plan by including the collection of drinking water occurrence data for a broader group of PFAS.
According to EPA, section 7311 of the National Defense Authorization Act for Fiscal Year 2020 (NDAA) specifies that EPA will include "all PFAS in UCMR 5 for which a drinking water method has been validated and that are not subject to a national primary drinking water regulation."
“EPA must also vary the frequency and schedule for monitoring based on the number of persons served, the source of supply, and the contaminants likely to be found,” according to the rule. It also stated that data collection for Legionella and four haloacetonitriles (dichloroacetonitrile, dibromoacetonitrile, trichloroacetonitrile, and bromochloroacetonitrile) would not be useful to EPA's regulatory deliberations.
The estimated total average national cost of this proposed action will be $21 million per year for the five-year effective period of the rule, according to EPA.
EPA will be hosting two identical virtual stakeholder meetings Apr. 6 from 9 to 12:30 p.m. EST and Apr. 7 from 1 to -4:30 p.m. EST, according to the EPA press release. The meeting will cover the proposed monitoring requirements, analyte selection, analytical methods, laboratory approval process, and groundwater representative monitoring plans (GWRMPs).
EPA will accept public comment on the proposed UCMR 5 for 60 days, added the press release, which can be submitted here.