The U.S. Environmental Protection Agency (EPA) announced on March 31, 2022 that it does not intend to regulate perchlorate in drinking water, retaining its July 2020 decision.The EPA concluded that the previous decision was based on the best available science.It’s been a long road since Massachusetts became one of the first states to regulate perchlorate in drinking water in 2006.(See the Holland & Knight newsletter, “Massachusetts first proposes 2 ppb drinking water and purification standard chemical perchlorate.”) Ironically, it was the swift and decisive action taken by states years ago that led the EPA to 2020 concluded that perchlorate levels in the environment decreased over time and did not meet the regulatory standards of the Safe Drinking Water Act (SDWA).
To recap, in June 2020, the EPA announced that it had determined that perchlorate did not meet SDWA’s regulatory standards as a drinking water contaminant, thus rescinding the 2011 regulatory decision.(See Holland & Knight’s Energy and Natural Resources Blog, “EPA Finalizes Its Perchlorate Decision,” June 23, 2020.) EPA’s final decision was published July 21, 2020.Specifically, the EPA determined that perchlorates are not “frequent and frequent.”levels of public health concern within the meaning of SDWA” and that regulation of perchlorate does not “provide meaningful opportunities to reduce health risks to those serving public water systems.”
Specifically, the EPA re-evaluated the 2011 regulatory decision and conducted multiple analyses over the years evaluating occurrence data collected from the Unregulated Contaminant Monitoring Rule (UCMR) and other monitoring in Massachusetts and California.(See Holland & Knight Alert, “EPA Proposes Perchlorate Rule After Years of Research,” June 10, 2019.) Reassessing based on this data, EPA concludes that there are only 15 regulated public water supplies in the U.S. The system will even exceed the recommended minimum value (18 µg/L).Therefore, pursuant to SDWA Section 1412(b)(4)(C), EPA determined that, based on available information, the benefits of establishing a national perchlorate primary drinking water regulation do not justify the associated costs.During the SDWA assessment and rulemaking process, EPA needs to determine whether regulation provides a meaningful opportunity to reduce health risks provided by the public water system before regulating.
The Natural Resources Defense Council immediately issued a statement condemning the action.Given its previous lawsuit challenging the 2020 decision, it remains to be seen whether that decision is really the end of the road.stay tuned.