EPA Publishes Changes to Cross-State Air Pollution Rule

On Monday, the U.S. Environmental Protection Agency (EPA) announced that it finalized revisions to the Cross-State Air Pollution Rule (CSAPR) Update. The rule reportedly assists areas affected by power plant pollution from upwind states in attaining the 2008 national ambient air quality standards (NAAQS) for ground-level ozone, commonly known as smog. The EPA’s public comment period for the proposed rule closed last December.

The agency’s press release explained that the rule responds to a September 2019 decision by the D.C. Circuit Court by addressing the “significant contribution” of pollution from particular upwind states to downwind states under the Clean Air Act’s “good neighbor” provision. More recently, several states filed a lawsuit challenging the agency’s inaction regarding the CASPR Update.

Under the EPA’s proposal, beginning this summer, power plants located in 12 states — Illinois, Indiana, Kentucky, Louisiana, Maryland, Michigan, New Jersey, New York, Ohio, Pennsylvania, Virginia, and West Virginia — must cut smog-forming nitrogen oxide emissions that exacerbate unhealthy air quality in downwind communities. Those power plants will be required to install and improve pollution controls.

The press release explained that nitrogen oxides cause respiratory issues and aggravate conditions like asthma, leading to school and work absences, emergency room visits, and even premature death. The EPA estimated that the CSAPR Update will reduce these emissions in the eastern United States by 17,000 tons beginning in 2021 compared to projections without the rule. 

When combined with the impact of initiatives already underway, the agency projects that nitrogen oxide emissions will be approximately 19% lower in 2021 than they were in 2019. The reduction is expected to have a direct impact on “asthma events” and related hospital visits and fatalities, returning public health and climate benefits at a value of $2.8 billion per year from 2021 to 2040.