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. Specifically, the SIP revisions add and update several definitions for consistency with the Federal regulations, update public participation requirements for PSD, clarify the applicability of ``source impact analysis'' for PSD, add an emissions offset banking provision for NNSR, and make administrative updates, such as typographical corrections and renumbering. Finally, the changes incorporate language that addresses the public notice rule provisions for NNSR, which removes the mandatory requirements to provide public notice in a newspaper and instead allows for electronic notice (``e- notice'') as an alternate noticing option for the State. EPA is approving these revisions pursuant to the Clean Air Act (CAA or Act) and implementing Federal regulations.