Section 52.923 - Approval status(a) With the exceptions set forth in this subpart, the Administrator approves Kentucky's plan for the attainment and maintenance of the national standards under section 110 of the Clean Air Act. Furthermore, the Administrator finds that the plan satisfies all requirements of part D, title 1, of the Clean Air Act as amended in 1977.(b) New Source review permits issued pursuant to Section 173 of the Clean Air Act will not be deemed valid by EPA unless the provisions of Section V of Appendix S of 40 CFR part 51 are met.45 FR 72157, Oct. 31, 1980, as amended at 79 FR 30050 , May 27, 2014