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

The Environmental Protection Agency (EPA) is approving a revision to the Washington State Implementation Plan (SIP) pertaining to adoption by reference of a Low Emission Vehicle (LEV) program by the State of Washington. The Clean Air Act (CAA) grants authority to the EPA to adopt Federal standards relating to the control of emissions from new motor vehicles, and generally preempts states from doing so.

The Environmental Protection Agency (EPA) is finalizing approval of State Implementation Plan (SIP) revisions submitted by the State of South Carolina, through the South Carolina Department of Health and Environmental Control (SCDHEC or Department), on April 24, 2020. The SIP revisions update the State's Prevention of Significant Deterioration (PSD) and Nonattainment New Source Review (NNSR) regulations.

The Environmental Protection Agency (EPA) is taking final action to approve a Nevada State Implementation Plan (SIP) revision submitted by the Nevada Department of Environmental Protection (NDEP). On September 27, 2010, the EPA redesignated the Las Vegas Valley area from nonattainment to attainment for the carbon monoxide (CO) national ambient air quality standard (NAAQS) and approved the State's CO maintenance plan ensuring the area would maintain the NAAQS for ten years through 2020.