a) An action required under Section 255.120(b)(1) and (2) of this Part to have a conformity determination for a specific pollutant will be determined to conform to the applicable SIP if, for each pollutant that exceeds the rates in Section 255.120(b)(1) and (2) of this Part, or otherwise requires a conformity determination due to the total of direct and indirect emissions from the action, the action meets the requirements of subsection (c) of this Section, and meets any of the following requirements:

1. 1) For any criteria pollutant, the total of direct and indirect emissions from the action are specifically identified and accounted for in the applicable SIP's attainment or maintenance demonstration;
2. 2) For ozone or nitrogen dioxide, the total of direct and indirect emissions from the action are fully offset within the same nonattainment or maintenance area through a revision to the applicable SIP or a similarly enforceable measure that effects emission reductions so that there is no net increase in emissions of that pollutant;

3. 3) For any criteria pollutant, except ozone and nitrogen dioxide, the total of direct and indirect emissions from the action meets the requirements specified in:

   1. A) Subsection (b) of this Section, based on areawide air quality modeling analysis and local air quality modeling analysis; or
   2. B) Subsection (a)(5) of this Section and, for local air quality modeling analysis, the requirement of subsection (b) of this Section;

4. 4) For CO or PM-10:

   1. A) Where the IEPA advises that an areawide air quality modeling analysis is not needed, the total of direct and indirect emissions from the action meets the requirements specified in subsection (b) of this Section, based on local air quality modeling analysis; or
   2. B) Where the IEPA advises that an areawide air quality modeling analysis is appropriate and that a local air quality modeling analysis is not needed, the total of direct and indirect emissions from the action meets the requirements specified in subsection (b) of this Section, based on areawide modeling, or meets the requirements of subsection (a)(5) of this Section; or

5. 5) For ozone or nitrogen dioxide, and for purposes of subsections (a)(3)(B) and (a)(4)(B) of this Section, each portion of the action or the action as a whole meets any of the following requirements:

   1. A) Where USEPA has approved a revision to an area's attainment or maintenance demonstration after 1990 and IEPA makes a determination as provided in subsection (a)(5)(A)(i) of this Section or where the State makes a commitment as provided in subsection (a)(5)(A)(ii) of this Section:

      1. i) The total of direct and indirect emissions from the action (or portion thereof) is determined and documented by IEPA to result in a level of emissions which, together with all other emissions in the nonattainment (or maintenance) area, would not exceed the emissions budgets specified in the applicable SIP;

      2. ii) The total of direct and indirect emissions from the action (or portion thereof) is determined by IEPA to result in a level of emissions which, together with all other emissions in the nonattainment (or maintenance) area, would exceed an emissions budget specified in the applicable SIP and the Director of IEPA makes a written commitment to USEPA which includes the following:

         a schedule for adoption and submittal of a revision to the SIP which would achieve the needed emission reductions prior to the time emissions from the Federal action would occur;

         identification of measures for incorporation into the SIP which would result in a level of emissions which, together with all other emissions in the nonattainment or maintenance area, would not exceed any emissions budget specified in the applicable SIP;

         a demonstration that all existing applicable SIP requirements are being implemented in the area for the pollutants affected by the Federal action, and that local authority to implement additional requirements has been fully pursued;

         a determination that the responsible Federal agencies have required all reasonable mitigation measures associated with their action; and

         written documentation including all air quality analyses supporting the conformity determination;

   2. B) The action (or portion thereof), as determined by the MPO, is specifically included in a current transportation plan and transportation improvement program which have been found to conform to the applicable SIP;
   3. C) The action (or portion thereof) fully offsets its emissions within the same nonattainment or maintenance area through a revision to the applicable SIP or an equally enforceable measure that effects emission reductions equal to or greater than the total of direct and indirect emissions from the action so that there is no net increase in emissions of that pollutant;

   4. D) Where USEPA has not approved a revision to the relevant SIP attainment or maintenance demonstration since 1990, the total of direct and indirect emissions from the action for the future years (described in Section 255.230 of this Part) do not increase emissions with respect to the baseline emissions:

      1. i) The baseline emissions reflect the historical activity levels that occurred in the geographic area affected by the proposed Federal action during:

         calendar year 1990;

         the calendar year that is the basis for the classification (or, where the classification is based on multiple years, the most representative year), if a classification is promulgated in 40 CFR 81, incorporated by reference in Section 255.160 of this Part; or

         the year of the baseline inventory in the PM-10 applicable SIP;

      2. ii) The baseline emissions are the total of direct and indirect emissions calculated for the future years (described in Section 255.230(d) of this Part using the historic activity levels (described in subsection (a)(5)(D)(i) of this Section) and appropriate emission factors for the future years; or
   5. E) Where the action involves regional water and/or wastewater projects, such projects are sized to meet only the needs of population projections that are in the applicable SIP.

b) The areawide and/or local air quality modeling analyses must:

1. 1) Meet the requirements in Section 255.230 of this Part; and

2. 2) Show that the action does not:

   1. A) Cause or contribute to any new violation of any standard in any area; or
   2. B) Increase the frequency or severity of any existing violation of any standard in any area.