DC Circuit grills EPA over reclassification of toxic chemical emission standard

In January 2020, the agency enacted new standards allowing industrial facilities to emit up to 25 tons of chemicals like mercury and arsenic.WASHINGTON (CN) — A D.C. Circuit panel on Monday seemed likely to strike down a new set of EPA regulations that allows thousands of industrial polluters to increase emissions of toxic chemicals like mercury and arsenic.The three-judge panel heard extensive arguments brought by a coalition of environmental advocacy groups who assert that the new regulations unraveled standards set by Section 112 of the Clean Air Act by allowing polluters to emit up to 10 tons of one chemical or 25 tons of several per year.Sanjay Narayan, attorney for the Sierra Club and representing the coalition, argued the new standards — enacted in January 2020 — effectively permitted such facilities to escape “Maximum Achievable Control Technology" standards and increase their toxic pollution. If a polluter emits just 9.9 tons of mercury they still comply with the standards under the EPA’s Reclassification Rule, Narayan said.“These are substances like mercury, dioxins, arsenic, cyanide substances that are extremely dangerous, even in very, very small quantities, sometimes a pound, sometimes a gram, sometimes less,” Narayan said. “What the rule says is that if a source complies with a MACT standard, compliance brings its emissions below 10 0r 25 tons, that major source threshold, then the source can stop complying with the standard, the standard is no longer applicable, and so long as the source remains below that 10-25 ton threshold, MACT does not apply.”U.S. Circuit Judge Gregory Katsas, a Donald Trump appointee, noted that the ultimate question in the case seemed to be what exactly counts as a major source of pollution, and whether the EPA has the discretion under the Clean Air Act to be more permissive in regulating emissions.Narayan argued that while the EPA can make distinctions between major sources of pollution and the lower “area sources,” the question should be whether polluters labeled an area source is then able to stop complying with the emissions standards.He argued that can’t be the case, otherwise it would be impossible to fully eliminate those sources of toxic chemical pollution, a major goal of the Clean Air Act.Katsas also noted that the panel, in a post-Chevrondeference world, did not have to defer to the agency’s interpretation of its authority under the Clean Air Act and could instead determine the proper reading themselves.The Supreme Court’s 2024 decision in *Loper Bright Enterprises v. Raimondo*gutted the deference, ending a long-standing practice that largely allowed executive agencies to operate under limited judicial review.Narayan agreed and said the EPA had abused its discretion by “shuffling these sources” into the new standards without any adequate explanation behind the decision.But Laura Glickman, representing the EPA, argued that the agency’s final reclassification rule reflected the best reading of the statute, where Congress specifically used the present tense to ensure it applied contemporaneously instead of historically.“A major source emits or has the potential to emit 10 tons per year of a single hazardous air pollutant, or 25 tons per year or more of multiple hazardous air pollutants,” Glickman said. “By contrast, an area source is anything that is not a major source. By using the present tense, ‘emit or has the potential to emit,’ Section 112’s definition of major source reflects a source’s current emissions.”U.S. Circuit Judge Robert Wilkins, a Barack Obama appointee, asked how the EPA squared that argument with Congress’ apparent intent to avoid “significant deterioration of air quality” via the Clean Air Act.Glickman asserted that Congress knew exactly how to prevent any backsliding if it wanted to, but did not include any such restrictions on reclassification.“If it were concerned about past emissions, it should have said a source that ‘at one point emitted 10 tons or more per year,’ but it did not say that, and the use of the present tense here and permitting reclassification is not inconsistent with the structure of the statute here,” Glickman said.U.S. Chief Circuit Judge Sri Srinivasan rounded out the three-judge panel.According to the Sierra Club, the Trump administration moved in February 2026 to allow coal-burning plants to emit 50% more mercury and in May 2025, exempted 68 power plants from emission standards after soliciting exemption requests.Subscribe to our free newslettersOur weekly newsletter Closing Arguments offers the latest about ongoing trials, major litigation and rulings in courthouses around the U.S. and the world, while the monthly Under the Lights dishes the legal dirt from Hollywood, sports, Big Tech and the arts.Additional Reads