EPA’s Unregulated Contaminant Monitoring Rule 5 to Include an Expanded List of PFAS Constituents and Additional Public Water Systems
The Safe Drinking Water Act (SDWA), as amended in 1996, requires that EPA establish a program to monitor specified unregulated contaminants every five years from Public Water Systems (PWS). The monitoring effort historically consisted of data collection from large PWS systems (serving > 10,000 people) and representative small PWS serving less than or equal to 10,000 people. EPA published the first Unregulated Contaminant Monitoring Rule (UCMR) in 1999. Twenty-plus years later, EPA is gearing up for its 5th cycle of unregulated contaminant monitoring under the pending UCMR 5. The data collected through UCMR 5 will be stored in the National Contaminant Occurrence Database and will be used to support the EPA Administrator’s determination as to whether regulation of previously unregulated contaminants is warranted. The selection of contaminants in the pending UCMR 5 cycle is based on a review of the Contaminant Candidate List (CCL), which is a list of contaminants that are not currently regulated by EPA under the national drinking water regulations.
As part of the pending UCMR 5 rulemakings, EPA is set to propose monitoring for over 20 different types of Per- and Polyfluoroalkyl Substances (PFAS). The proposed UCMR 5 rulemaking was originally scheduled for publication in 2020, however due to delays, we now anticipate it to be early 2021. Following a public comment period, the final UCMR 5 rulemaking is scheduled to be released by the end of 2021. Once finalized, the UCMR 5 monitoring period will cover the years 2022 through 2026. The inclusion of an expanded list of PFAS in the UCMR 5 would fulfill a key commitment in EPA's 2019 PFAS Action Plan by proposing the collection of more drinking water occurrence data for a broader group of PFAS, utilizing newer analytical methods at lower minimum reporting levels than previously possible.
Also of importance to the UCMR 5 rulemaking efforts, the SDWA amendments under P.L. 115–270, known as America’s Water Infrastructure Act of 2018 (AWIA), will now expand unregulated contaminant monitoring requirements to include all public water systems serving 3,300-10,000 individuals. This requirement will take effect on October 23, 2021 (three years after the enactment of AWIA). This amendment to the SDWA could result in approximately 5,000 additional PWS being brought into the UCMR 5 monitoring program.