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special options for modeling air quality near intersections, street canyons and parking facilities. — CALINE4 used the EMFAC2002 emission factors as part of its analysis. In general, the transport and concentration of pollutants from vehicular sources are influenced by three principal meteorological factors: wind direction,wind speed, and atmospheric stability, which accounts for the effects of dispersion or mixing in the atmosphere. Wind direction,which — influences the accumulation of pollutants at a particular receptor location,was chosen to maximize pollutant concentrations at the receptor. In applying the CALINE4 modeling, the wind angle was varied to determine the worst-case wind direction resulting in the maximum — concentrations. For short-term average impacts,computations was performed using a wind speed of 1 meter/second, stability class F"very stable",representing a worst case assumption of conditions and an aerodynamic roughness coefficient of 400 cm,typical of the environment surrounding the Proposed Project. The SJVQMD has a significance threshold for health risk exposure to diesel emissions of 10 cancers per million for 70-year exposure. Accordingly, the SJVAQMD CEQA Guidelines indicate the primary concern from diesel engine exhaust emissions is a potential long-term health — risk to sensitive receptors. Receptors were placed at distances of 1090, 1190, and 1500 meters from the source(designated as the center of the Project site).. Annualized average emissions from 2007 and 2021 from onsite equipment were determined. A generalized emission area source with dimensions of 300 by 300 meters with a height of 5 meters was used. Rural dispersion coefficients were used. Refined Dispersion Modeling This section presents the methodology used for the refined dispersion modeling analysis. This section addresses all of the fundamental components of an air dispersion modeling analysis including: • Model selection and options; • Receptor spacing and location; • Meteorological data; and — • Source release characteristics. The dispersion modeling analysis estimated ambient DPM concentrations as a result of — incremental project emission increases and then determined differential cancer risk. The dispersion modeling included onsite equipment. MODEL SELECTIONAND OPTIONS The AERMOD dispersion model(Version 9935 1) was used for the modeling analysis. AERMOD is the U.S. EPA preferred dispersion model for general industrial purposes. The 16