Bloomberg Law
Sept. 21, 2020, 10:00 AM

EPA to Defend Clean Air Rule as Compliant With Ozone Limits

Amena H. Saiyid
Amena H. Saiyid

The EPA will be defending itself at the D.C. Circuit Tuesday against claims that it created illegal regulatory loopholes for communities that can’t meet national air quality limits for ozone.

A coalition of environmental groups, led by the Sierra Club, is challenging a 2018 rule that allows states to use a trading program to offset sources of ozone forming pollution, among other things.

The lawsuit in U.S. Court of Appeals for the District of Columbia Circuit also challenges the approaches the Environmental Protection Agency is giving communities to show they’ve made reasonable progress to meet ozone standards.

Ozone is one of six key pollutants for which the EPA has set national air quality standards. Ground level ozone, a key component of smog, is formed when fossil fuel combustion byproducts, nitrogen oxide and volatile organic compounds react in the presence of sunlight.

The agency updated the health-based standard of 70 parts per billion standard in 2015 because ozone is known to inflame the lungs, constrict breathing, cause asthma attacks and exacerbate other respiratory and cardiac illnesses enough to cause fatalities.

Clean Air Act Reading

Both sides intend to persuade D.C. Circuit Judges David S. Tatel, Gregory G. Katsas, and Harry T. Edwards to support their interpretation of the Clean Air Act and its application to ozone standards.

The Sierra Club coalition alleges the EPA’s 2018 rule should be vacated because it departs from the plain language of the Clean Air Act, which requires reductions in actual emissions of ozone precursors that cause an area to violate the national standard.

The EPA hasn’t explained why it chose to violate the plain language with its own interpretation, the plaintiffs allege. The agency argued that it’s exercised its discretion in a well-reasoned, technically sound manner.

The coalition also alleges that the EPA is illegally allowing major sources of air pollution to offset their increases in one ozone-forming pollutant owing to construction or expansion with reductions in another precursor through a trading program.

For instance, they claim when a pollution source has major status because of volatile organic compound emissions, the air pollutant in question is a “volatile organic compound.” The same holds for major sources for nitrogen oxides, they argue.

“Volatile organic compounds and oxides of nitrogen are not the same thing, and neither is a precursor of the other,” the groups told the court in their opening brief.

Moreover, the EPA allegedly is letting major sources such as power plants and refineries to use banked pollution credits for cuts that took place years earlier. Doing so allows them to meet their environmental obligations instead of making actual cuts to the targeted pollutants as the law requires, the plaintiffs allege.

Countering the coalition’s claims, the EPA said the rule doesn’t allow for trading of ozone-forming pollutants unless it achieves at least the same ozone reduction as an actual ton-for-ton cut in the targeted pollutant would.

State Compliance

The coalition also alleges that the EPA is illegally allowing states to show that non-compliant communities have met the pollution reduction requirements by relying on controls and measures that were previously predicted to achieve reductions without checking whether actual air emissions decreased.

The Clean Air Act requires these contingency measures to go into effect in areas that fail to attain the federal limits. However, the coalition said the EPA’s rule allows the contingency measures requirement to be met with steps that have already failed to meet the pollution reduction requirements.

“They have do something new—take new steps—because the steps they took have failed and led to continued nonattainment,” Earthjustice attorney Seth Johnson, who is representing the Sierra Club-led coalition, told Bloomberg Law.

Supporters for Each Side

The coalition’s stance is backed by the Texas-based nonprofit Caring for Pasadena communities that filed a friend-of-court brief because of the disproportionate impact that high ozone levels are having on environmental justice communities located along Houston’s Ship Channel.

In contrast, the Texas Commission on Environmental Quality is intervening on EPA’s behalf because it’s taking advantage of the trading program to meet federal ozone limits for its communities, including Houston.

Also backing the EPA’s stance are the American Chemistry Council, American Petroleum Institute, U.S. Chamber of Commerce, National Association of Manufacturers and National Mining Association, who have filed friend-of court briefs.

The Sierra Club coalition consists of Downwinders at Risk, Conservation Law Foundation, National Parks Conservation Association, and Physicians for Social Responsibility-Los Angeles.

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 case is Sierra Club v. EPA, D.C. Cir., No. 15-01465, oral arguments scheduled 9/22/20.

To contact the reporter on this story: Amena H. Saiyid in Washington at

To contact the editors responsible for this story: Anna Yukhananov at; Rebecca Baker at