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36 FR 22398, Nov. 25, 1971, unless otherwise noted.
69 FR 23996, Apr. 30, 2004, unless otherwise noted.
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Upon a determination by EPA that an area designated nonattainment for the 8-hour ozone NAAQS has attained the standard, the requirements for such area to submit attainment demonstrations and associated reasonably available control measures, reasonable further progress plans, contingency measures, and other planning SIPs related to attainment of the 8-hour ozone NAAQS shall be suspended until such time as: the area is redesignated to attainment, at which time the requirements no longer apply; or EPA determines that the area has violated the 8-hour ozone NAAQS.
[70 FR 71702, Nov. 29, 2005]