Section 52.1387 - Visibility protection(a) The requirements of section 169A of the Clean Air Act are not met because the plan does not include approvable procedures for protection of visibility in mandatory Class I Federal areas.(c) Montana's November 7, 2017 Progress Report meets the applicable regional haze requirements set forth in § 51.308(g) and (h) .52 FR 45138, Nov. 24, 1987, as amended at 82 FR 3129 , Jan. 10 2017; 84 FR 53061 , Oct. 4, 2019 As amended at 82 FR 3129 , 1/10/2017; 84 FR 53061 , 11/4/2019