EPA is taking final action to approve portions of a revision to the Tennessee State Implementation Plan (SIP), submitted by the Tennessee Department of Environment and Conservation (TDEC) through the Division of Air Pollution Control, to EPA on October 4, 2012, for parallel processing. TDEC submitted the final version of this SIP revision on May 10, 2013. The SIP revision approved in this action modifies Tennessee's New Source Review (NSR) Prevention of Significant Deterioration (PSD) program to adopt, into the Tennessee SIP, federal regulatory requirements regarding PSD increments for fine particles with an aerodynamic diameter of less than or equal to 2.5 micrometers. EPA is approving portions of Tennessee's May 10, 2013, SIP revision because the Agency has made the determination that these portions of the SIP revision are in accordance with the Clean Air Act (CAA or Act) and EPA regulations regarding NSR permitting.