OAR 340-225-0040: Air Quality Models

All modeled estimates of ambient concentrations required under this division must be based on the applicable air quality models, data bases, and other requirements specified in 40 CFR part 51, Appendix W, "Guidelines on Air Quality Models (Revised)." Where an air quality impact model specified in 40 CFR part 51, Appendix W is inappropriate, the methods published in the FLAG are generally preferred for analyses in PSD Class I areas. Where an air quality impact model other than that specified in 40 CFR part 51, Appendix W is appropriate in PSD Class II and III areas, the model may be modified or another model substituted. Any change or substitution from models specified in 40 CFR part 51, Appendix W is subject to notice and opportunity for public comment and must receive prior written approval from DEQ and the EPA. [NOTE: This rule is included in the State of Oregon Clean Air Act Implementation Plan that EQC adopted under OAR 340-020-0040.] [NOTE: View a PDF of 40 C.F.R. Part 51, Appendix W by clicking on "Tables" link below.] [ED. NOTE: To view attachments referenced in rule text, click here to view rule.]