The Environmental Protection Agency said yesterday it will finally propose an enforceable limit for perchlorate in tap water, and it is doing it because a federal court left the agency no choice. EPA officials framed the move as compliance with a judicial order even while arguing that the rule will yield only modest public health gains for most communities.
According to The Associated Press, the EPA will seek public comment on possible limits of 20, 40 and 80 parts per billion and would require water utilities to begin monitoring for perchlorate. The agency told reporters it expects fewer than one tenth of 1% of regulated systems to find perchlorate above any of those options, while roughly 66,000 systems would fall under the new rule.
How This Fight Landed Back On EPA’s Desk
The proposal is the latest turn in a long legal and regulatory loop that started when EPA decided in 2011 that perchlorate met the Safe Drinking Water Act criteria for a national standard. In 2019 the agency floated a proposal that revisited the technical basis for possible limits, then in 2020 tried to withdraw its earlier determination. The U.S. Court of Appeals for the D.C. Circuit stepped in, vacated that withdrawal and sent the issue back to EPA to finish the job, as detailed in the Federal Register and the court’s opinion.
What Could Change For Water Systems
If finalized, the rule would set a National Primary Drinking Water Regulation for perchlorate and trigger mandatory monitoring, public reporting and, where needed, treatment for systems that exceed the chosen limit. EPA materials point out that analytical methods and treatment technologies already exist, but also acknowledge that smaller systems in particular could face significant administrative and compliance costs. State and federal funding programs could help communities pay for monitoring and treatment if they are pushed over the threshold.
Why Perchlorate Worries Health Officials
Perchlorate can interfere with the thyroid’s ability to take up iodide, a pathway that matters most for fetal and infant brain development. That is why regulators and health agencies focus on exposures for pregnant people and very young children. In California, the Office of Environmental Health Hazard Assessment has set a public health goal of 1 part per billion, and the state’s enforceable maximum contaminant level is 6 ppb, benchmarks public health advocates frequently cite as tougher than the federal options now on the table.
Bay Area Hot Spots And Local Scrutiny
Monitoring and NGO surveys have found perchlorate in multiple California counties, including Santa Clara and Sonoma, so Bay Area water utilities and local health agencies are expected to comb through the EPA docket closely. Local outlets and national coverage, including reporting by The San Diego Union-Tribune, picked up the announcement. EPA has said it will stick to the court ordered timeline under the consent decree while still allowing a public comment period as it finalizes its approach.
Politics, Public Comments And The Number To Watch
The proposal kicks off a months long rulemaking process. EPA will take technical comments and feedback from states, utilities and advocates before choosing a final standard, and communities will be watching to see whether that number lands closer to state health goals or to the agency’s higher proposed options. Environmental and public health groups have welcomed the return of this rulemaking, if not the pace. As NRDC attorney Sarah Fort put it, “Members of the public deserve to know whether there’s rocket fuel in their tap water,” a line that has echoed through national coverage of the announcement.
