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Former National Compliance Initiative: Reducing Air Pollution from the Largest Sources

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

The EPA returned work in these areas to the core enforcement and compliance assurance program at the end of FY 2019. The EPA and state regulatory approaches and enforcement efforts in the coal-fired utilities sector have resulted in a 89 percent reduction in sulfur dioxide emissions and an 83 percent reduction in nitrogen oxide emissions since 1999.  The EPA has  also required controls or commenced investigations at 100 percent, 93 percent, and 90 percent of facilities in the cement, glass 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 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. 


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