WAC 173-400-110, 173-400-111, 173-400-112, and 173-400-113 apply statewide except where a permitting authority has adopted its own new source review regulations. The permitting authority that is reviewing an application to establish a new source or modification in an attainment or unclassifiable area shall issue an order of approval if it determines that the proposed project satisfies each of the following requirements:

(1) The proposed new source or modification will comply with all applicable new source performance standards, national emission standards for hazardous air pollutants, national emission standards for hazardous air pollutants for source categories, emission standards adopted under chapter 70.94 RCW and, for sources regulated by an authority, the applicable emission standards of that authority.

(2) The proposed new source or modification will employ BACT for all pollutants not previously emitted or whose emissions would increase as a result of the new source or modification.

(3) Allowable emissions from the proposed new source or the increase in emissions from the proposed modification will not cause or contribute to a violation of any ambient air quality standard. If the modeled concentrations of allowable emissions from the proposed new source or the increase in emissions from the proposed modification are below the levels in Table 4a, the proposed source does not contribute to a violation of an ambient air quality standard.

(4)(a) If the projected impact of the allowable emissions from the proposed new major stationary source (as defined in WAC 173-400-810) or the projected impact of the increase in allowable emissions from the proposed major modification (as defined in WAC 173-400-810) at any location within a nonattainment area does not exceed the following levels for the pollutants for which the area has been designated nonattainment, then the proposed new source or modification will not be considered to cause or contribute to a violation of an ambient air quality standard:

(b) If the projected impact of the allowable emissions from the proposed new major stationary source (as defined in WAC 173-400-810) or the projected impact of the increase in allowable emissions from the proposed major modification (as defined in WAC 173-400-810) results in a projected impact at any location inside a nonattainment area above the appropriate value in Table 4a of this section may use an offsetting emission reduction or other method identified in 40 C.F.R. Part 51 Appendix S, Sections III and IV.A which reduce the projected impacts to the above values or less. If the owner or operator of the proposed new major stationary source or major source proposed to be modified is unable to reduce emissions or obtain offsetting emissions reductions adequate to reduce modeled impacts below the values in Table 4a of this section, then the permitting authority shall deny approval to construct and operate the proposed new major stationary source or major modification.

(5) If the proposal is a new major stationary source or a major modification as defined in WAC 173-400-720, then it must also comply with WAC 173-400-700 through 173-400-750.