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National Compliance Initiative: Reducing Air Pollution from the Largest Sources

a coal-fired power plant
A coal-fired power plant


The New Source Review (NSR) and Prevention of Significant Deterioration (PSD) requirements of the CAA require certain large industrial facilities to install state-of-the-art air pollution controls when they build new facilities or make significant modifications to existing facilities. The EPA began this initiative as it relates to the power sector in 1998, after EPA investigations revealed that many facilities had failed to install pollution controls after modifications, causing them to emit pollutants that can impact air quality and public health. 

FY2019 Update

The EPA and state regulatory approaches and enforcement efforts in this sector have resulted in a 90 percent reduction in sulfur dioxide emissions and an 83 percent reduction in nitrogen oxide emissions since 1997, while gross generation has increased by 10 percent. The EPA has required controls or commenced investigations at 91 percent, 96 percent, and 90 percent of facilities in the glass, cement, and acid manufacturing sectors, respectively. Accordingly, the Agency believes that this NCI no longer presents a significant opportunity to affect nonattainment areas or vulnerable populations nationwide. The EPA is proposing to return work in these areas to the core program in FY 2020.

EPA will continue to monitor the progress of existing settlement agreements to ensure actions required under those settlements are implemented and air pollution reduction targets are met. 


The following map and charts show EPA’s actions in targeting and reducing air pollution from the largest sources.

Map of coal-fired electric utilities: current level of NSR/PSD air pollution controls