The Environmental Protection Agency (EPA) is finalizing the approval of changes to the North Carolina State Implementation Plan (SIP), submitted by the State of North Carolina through the North Carolina Department of Environmental Quality (NCDEQ), Division of Air Quality (DAQ), through a letter dated April 13, 2021. This SIP revision includes changes to a subset of NCDEQ's regulations regarding emission control standards. EPA is approving these changes pursuant to the Clean Air Act (CAA or Act).

The Environmental Protection Agency (EPA) is approving a State Implementation Plan (SIP) revision submitted by the State of South Carolina, through the South Carolina Department of Health and Environmental Control (SC DHEC), on November 4, 2016. This revision was submitted by South Carolina in response to a finding of substantial inadequacy and SIP call published by EPA on June 12, 2015, of provisions in the South Carolina SIP related to excess emissions during startup, shutdown, and malfunction (SSM) events.

The Environmental Protection Agency (EPA) is approving a portion of a State Implementation Plan (SIP) revision to the Mecklenburg County portion of the North Carolina SIP, hereinafter referred to as the Mecklenburg County Local Implementation Plan (LIP). The revision was submitted through the North Carolina Division of Air Quality (NCDAQ), on behalf of Mecklenburg County Air Quality (MCAQ), via a letter dated April 24, 2020, which was received by EPA on June 19, 2020.

The Environmental Protection Agency (EPA) is finalizing the approval of a revision to the Kentucky State Implementation Plan (SIP), submitted by the Commonwealth of Kentucky, through the Kentucky Division for Air Quality (KDAQ), on March 29, 2021. The revision was submitted by KDAQ on behalf of the Louisville Metro Air Pollution Control District (District or Jefferson County), which has jurisdiction over Jefferson County, Kentucky.