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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.
The Denver Regional Council of Governments (DRCOG) submitted a NOX exemption petition to the EPA on May 25, 1994 and submitted supporting documentation via a letter dated August 1, 1994. This petition requested that the Denver metropolitan area, a transitional ozone nonattainment area, be exempted from the requirement to meet the NOX provisions of the Federal transportation and general conformity rule with respect to ozone. The exemption request was based on monitoring data which demonstrated that the National Ambient Air Quality Standard for ozone had been attained in this area for the 3 years prior to the petition. The EPA approved this exemption request on July 28, 1995.
[60 FR 40291, Aug. 8, 1995]