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Nomenclature changes to part 52 appear at 81 FR 74586, Oct. 26, 2016.
(a) The requirements of section 169A of the Clean Air Act (CAA) are met because the Regional Haze plan submitted by Iowa on March 25, 2008, and supplemented on May 14, 2019, includes fully approvable measures for meeting the requirements of the Regional Haze Rule including 40 CFR 51.308(d)(3) and (e) with respect to emissions of NOX and SO2 from electric generating units.
(b) The requirements of section 169A of the CAA are met because the Regional Haze plan submitted by Iowa on August 15, 2023, includes fully approvable measures for meeting the requirements of the Regional Haze Rule in 40 CFR 51.308.
[90 FR 37403, Aug. 5, 2025]