42 U.S.C. § 7514

section 7407(d) of this titleNovember 15, 1990Any State containing an area designated or redesignated under as nonattainment with respect to the national primary ambient air quality standards for sulfur oxides, nitrogen dioxide, or lead subsequent to , shall submit to the Administrator, within 18 months of the designation, an applicable implementation plan meeting the requirements of this part.

section 7407(d)(1)(C)(i) of this titleNovember 15, 1990November 15, 1990section 7514a of this titleAny State containing an area designated nonattainment with respect to national primary ambient air quality standards for sulfur oxides or nitrogen dioxide under , but lacking a fully approved implementation plan complying with the requirements of this chapter (including this part) as in effect immediately before , shall submit to the Administrator, within 18 months of , an implementation plan meeting the requirements of subpart 1 (except as otherwise prescribed by ).