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42 U.S.C. 7401 et seq.
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Nomenclature changes to part 52 appear at 81 FR 74586, Oct. 26, 2016.
With the exceptions set forth in this subpart, the Administrator approves Montana's plans for the attainment and maintenance of the national standards under section 110 of the Clean Air Act. Furthermore, the Administrator finds the plans satisfy all requirements of Part D, Title I, of the Clean Air Act as amended in 1977, except as noted below.
[45 FR 2036, Jan. 10, 1980]