allowed on State authority on a case-by-case basis. Such allowances must also not cause exacerbate a violation of the NAAQS nor impeded an area’s attainment strategy in any way. 

## 8.1.2.3. Air Quality Modeling for CO and PM 

Under General Conformity, the state agency responsible for preparing the SIP can allow either an area-wide or local-scale dispersion assessment of CO or PM as a means of demonstrating General Conformity. The results of the air quality modeling must show that the action does not cause or contribute to any new violation of any NAAQS in any area and does not increase the frequency or severity in any area. 

## 8.1.2.4. Commitment to Revise the SIP 

If direct and indirect emissions attributable to an action cannot be identified in an approved SIP, cannot be demonstrated via air quality modeling that a violation or exacerbation of the NAAQS would not be incurred, and/or cannot be mitigated or offset to zero, the only remaining option to demonstrate General Conformity is to petition the state Governor (or their designee) to revise the SIP. The Governor or their designee (i.e., the air agency) must then submit a commitment to EPA providing the following: 

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

• Identification of specific measures for incorporation into the SIP which would result in a level of emissions which, together with all other emissions in the nonattainment 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 implement additional requirements has been fully pursued; 

• A determination that the responsible f ederal agencies have required all reasonable mitigation measures associated with their action; and 

• Written documentation including all air quality analyses supporting the conformity determination. 

Generally speaking, a SIP including the commitments above must be submitted to EPA for approval within 18 months of the Conformity Determination and the agency cannot undertake the action prior to final approval of the SIP revision by EPA. 

## 8.1.3. Interagency and Public Review 

When a Draft General Conformity Determination is prepared, public and agency involvement is required. The Draft must be advertised via public notice in a daily newspaper of local circulation and air quality stakeholders (including EPA, state/local air quality government, and the general public) are allowed to provide comment for a 30- day period. The General Conformity Rule allows for this comment period to run concurrent with any other public involvement, including 

