40 CFR 51.907
§ 51.907 For an area that fails to attain the 8-hour NAAQS by its attainment date, how does EPA interpret sections 172(a)(2)(C)(ii) and 181(a)(5)(B) of the CAA?
United States · 40 CFR — Protection of Environment · Status: effective
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- 40 CFR 51.907, § 51.907 For an area that fails to attain the 8-hour NAAQS by its attainment date, how does EPA interpret sections 172(a)(2)(C)(ii) and 181(a)(5)(B) of the CAA?, United States, version 1 as recorded 2026-07-09, yourstate.us, https://yourstate.us/provision/169884
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Full text
For purposes of applying sections 172(a)(2)(C) and 181(a)(5) of the CAA, an area will meet the requirement of section 172(a)(2)(C)(ii) or 181(a)(5)(B) of the CAA pertaining to 1-year extensions of the attainment date if:
(a) For the first 1-year extension, the area's 4th highest daily 8-hour average in the attainment year is 0.084 ppm or less.
(b) For the second 1-year extension, the area's 4th highest daily 8-hour value, averaged over both the original attainment year and the first extension year, is 0.084 ppm or less.
(c) For purposes of paragraphs (a) and (b) of this section, the area's 4th highest daily 8-hour average shall be from the monitor with the highest 4th highest daily 8-hour average of all the monitors that represent that area.
Legislative history
This is a federal regulation, adopted through agency rulemaking under the Administrative Procedure Act — not enacted by a recorded vote of Congress.