51.915—What emissions inventory requirements apply under the 8-hour NAAQS?
For each nonattainment area subject to subpart in accordance with § 51.903, the emissions inventory requirements in sections 182(a)(1) and 182(a)(3) of the Act shall apply, and such SIP shall be due no later 2 years after designation. For each nonattainment area subject only to title I, part D, subpart 1 of the Act in accordance with § 51.902(b), the emissions inventory requirement in section 172(c)(3) of the Act shall apply, and an emission inventory SIP shall be due no later 3 years after designation. For purposes of defining the data elements for the emissions inventories for these areas, the ozone-relevant data element requirements under 40 CFR part 51 subpart A apply.