EPA Disapproves Oklahoma's PM 2.5 Implementation Plan Provisions

Summary

The Environmental Protection Agency (EPA) has disapproved certain provisions of Oklahoma's State Implementation Plan (SIP) related to particulate matter less than 2.5 micrometers in diameter (PM 2.5 ) due to inconsistencies with federal laws and regulations. The disapproval affects the adoption and implementation of PM 2.5 significant impact levels (SILs) and significant monitoring concentration (SMC) in the state's PSD permitting requirements.