The D.C. Circuit Court of Appeals today upheld the Environmental Protection Agency’s (EPA) cross-state ozone rule, which requires upwind states to reduce pollution from power plants.

Environmental groups defended EPA’s Revised Cross-State Air Pollution Update Rule after industry challenged it in court in July 2021. While the new rule improves air quality by requiring coal-burning power plants to reduce emissions that cause the formation of ozone — the main component of smog — greater reductions are still needed. Ground-level ozone causes asthma attacks and other respiratory problems and is even linked to premature deaths. It also damages plants and forests, stunting tree and crop growth.

“We are pleased that the Court has recognized the need for EPA to reduce cross-state ozone pollution as expeditiously as practicable so that people in both upwind and downwind states can breathe easier,” said Earthjustice Attorney Kathleen Riley. “We expect EPA to carry this win forward and finalize a strong, new cross-state ozone rule, the Good Neighbor Rule, on March 15.”

In this lawsuit, Earthjustice represents Downwinders at Risk, Texas Environmental Justice Advocacy Services, Appalachian Mountain Club, Sierra Club, and Environmental Defense Fund. Clean Air Task Force represents Clean Wisconsin.