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EPA Reverses Its ‘Once In, Always In’ Air Pollution Policy (1)

Oct. 1, 2020, 7:09 PMUpdated: Oct. 1, 2020, 7:46 PM

The EPA will no longer enforce its “once in, always in” toxic air policy that meant industrial sources, such as chemical plants and refineries, were locked into years of pollution controls based on their estimated emissions, the agency announced Thursday.

Under the rule (RIN:2060-AM75), the Environmental Protection Agency determined it has no authority, under the plain language of the Clean Air Act, to restrict when a source of air emissions may be classified as relatively large or small.

“This rule, which follows on a 2018 guidance memorandum, will end regulatory interpretations that discourage facilities from investing in better emissions technology,” EPA Administrator Andrew Wheeler said in a statement.

That allows facilities to switch statuses depending on the scale of their emissions. A facility’s status determine whether it must install more or fewer emissions controls.

The rule is likely to draw legal attention, said Debra Jezouit, partner and deputy department chair of the environmental practice at Baker Botts LLP in Washington. Both the Sierra Club and the Natural Resources Defense Council said Thursday they will challenge the rule.

“There is no question that the rule will be appealed by environmental groups and potentially some states who are concerned that sources could increase their emissions above the level that they currently must meet under the NESHAPs,” or National Emission Standards for Hazardous Air Pollutants, she said.

The agency’s decades-old “once in, always in” policy required sources of toxic air pollution to implement strict “major” pollution controls, even if their emissions of such pollutants fell below mandated Clean Air Act thresholds.

Major sources are required to install the maximum level of pollution controls.

Major Versus ‘Area’ Source

The definitions of “major source” of emissions and “area source” of emissions “contain no language fixing a source’s status at any particular point in time,” the agency said in the rule.

The thresholds for area and major sources are 10 tons for a single hazardous pollutant and 25 tons for two or more pollutants.

The rule also clarifies compliance dates, notification, and record-keeping requirements that apply when sources choose to reclassify to “area source” status, or when sources revert back to “major source” status.

Manufacturers, petroleum companies, and pulp mills affected by the rule support the EPA’s reversal. Environmental groups and the state of California challenged the EPA when it tried enforcing a reversal of the toxic air pollution policy through guidance.

The rule allows industrial polluters to skirt the Clean Air Act’s intended restrictions on air emissions, the Sierra Club said in a statement.

“We will fight this reckless and unlawful rollback, in order to ensure that the American public is safe from dangerous air pollution,” Mary Anne Hitt, national director of campaigns for the Sierra Club, said in a statement.

The Sierra Club has received funding from Bloomberg Philanthropies, the charitable organization founded by Michael Bloomberg. Bloomberg Law is operated by entities controlled by Michael Bloomberg.

The rule hasn’t yet been published in the Federal Register.

(Updates with additional reporting throughout.)

To contact the reporter on this story: Sylvia Carignan in Washington at

To contact the editor responsible for this story: Anna Yukhananov at