42 U.S.C. § 7471 : US Code - Section 7471: Plan requirements

Search 42 U.S.C. § 7471 : US Code - Section 7471: Plan requirements

In accordance with the policy of section 7401(b)(1) of this
title, each applicable implementation plan shall contain emission
limitations and such other measures as may be necessary, as
determined under regulations promulgated under this part, to
prevent significant deterioration of air quality in each region (or
portion thereof) designated pursuant to section 7407 of this title
as attainment or unclassifiable.