Section 52.1165 - Significant deterioration of air quality(a) The requirements of sections 160 through 165 of the Clean Air Act are not met, since the plan does not include approvable procedures for preventing the significant deterioration of air quality.(b) Regulation for preventing significant deterioration of air quality. The provisions of § 52.21 except paragraph (a)(1) are hereby incorporated and made a part of the applicable State plan for the State of Massachusetts.43 FR 26410, June 19, 1978, as amended at 68 FR 11323, Mar. 10, 2003; 68 FR 74489, Dec. 24, 2003