The Environmental Protection Agency (EPA) on March 15 issued the final “Good Neighbor Plan,” its latest iteration of the Cross-State Air Pollution Rule (CSAPR) that could require coal, oil, or gas steam power plants in 22 states to reduce their nitrogen oxide (NOx) emissions levels by 50% by 2027 compared to the 2021 ozone season.
Issued under the Clean Air Act’s (CAA’s) “good neighbor” or “interstate transport” provision, the EPA’s new “Good Neighbor Plan” essentially seeks to ensure that the nearly two dozen “upwind” states will incrementally tamp down their annual emissions of NOx—an ozone-precursor pollutant—during ozone seasons that run from May through September. The effort is geared to help “downwind” states attain and maintain the EPA’s 2015 Ozone National Ambient Air Quality Standards (NAAQS), an Obama-era smog rule.
The EPA said the plan will ensure “that emissions reductions will happen as quickly as possible and be aligned with Clean Air Act deadlines for states to achieve the 2015 ozone NAAQS—which vary according to the severity of nonattainment.” The initial phase of NOx emissions reductions will take effect “as soon as possible” to meet the Aug. 3, 2024, attainment date for areas classified as “moderate attainment.” However, more emissions reductions will be required at the beginning of the 2026 ozone season to meet the Aug. 3, 2027, attainment date for “serious” nonattainment areas, it said.