Section 52.833 - Significant deterioration of air quality(a) The requirements of sections 160 through 165 of the Clean Air Act are met, except for sources seeking permits to locate on Indian lands in the state of Iowa; and certain sources affected by the stack height rules described in a letter from Iowa dated April 22, 1987.(b) Regulations 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 Iowa for sources wishing to locate on Indian lands; and certain sources as identified in Iowa's April 22, 1987, letter. 71 FR 16053 , Mar. 30, 2006