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City of Santa Ana <br />Environmental Checklist <br />issues relating to transportation, the economy, community development, and the environment. <br />SCAG is the federally designated metropolitan planning organization (MPO) for the majority of the <br />southern California region and is the largest MPO in the nation. With respect to air quality planning, <br />SCAG has prepared the Regional Comprehensive Plan and Guide (RCPG) for the region, which <br />includes Growth Management and Regional Mobility chapters that form the basis for the land use <br />and transportation components of the AQMP. These chapters are utilized in the preparation of air <br />quality forecasts and the consistency analysis that is included in the AQMP. <br />Methodology <br />Construction <br />Mass daily combustion emissions, fugitive PM10 and PM2.5, and off - gassing emissions (e.g., <br />evaporative emissions of volatile organic compounds [VOCs] from the application of architectural <br />coatings and asphalt paving) were compiled using CalEEMod, which is an emissions <br />estimation /evaluation model developed in collaboration with air quality management districts of <br />California. <br />The CalEEMod model separates the construction process into multiple phases that account for <br />everything from structure demolition and site clearing to asphalt paving and the application of <br />architectural coatings. Site preparation emissions (e.g., grading and excavation) would include <br />fugitive dust emissions from soil disturbance activity, as well as combustion exhaust emissions from <br />onsite construction equipment, haul truck trips, and worker commute trips. Structure erection and <br />finishing emissions would include combustion exhaust emissions from onsite construction <br />equipment, haul truck trips, and worker commute trips, as well as fugitive off - gassing emissions <br />from the application of architectural coatings and asphalt paving. <br />Assumptions regarding construction phasing and equipment use were developed based on <br />information received from the project applicant. A complete listing of the construction equipment by <br />phase, construction phase duration assumptions, and changes to modeling default values used in <br />this analysis is included within the CaiEEMod printout sheets that are provided in Appendix A of this <br />IS /MND. <br />Operations <br />The CalEEMod software was also used to compile the mass daily emissions estimates from mobile <br />and area sources that would occur during long -term project operations. In calculating mobile- source <br />emissions, the CalEEMod default trip assumptions were applied to arrive at the total vehicle miles <br />traveled (VMT). Area- source emissions were compiled using CalEEMod default assumptions. <br />The analysis of roadway CO impacts followed the protocol recommended by Caltrans and published <br />in their Transportation Project -Level Carbon Monoxide Protocol (Garza 1997). It is also consistent <br />with procedures identified through the SCAQMD's CO modeling protocol. For any intersection that <br />shows potential to generate a CO hotspot by failing SCAQMD- recommended screening criteria, local <br />area CO concentrations are evaluated using the CALiNE 4 line- source dispersion model developed <br />by the California Department of Transportation (Caltrans) combined with EMFAC2012 emission <br />factors. All emissions calculation worksheets and air quality modeling output files are provided in <br />Appendix A. <br />The Academy Charter High School 3 19 tune 2012 <br />Initial Study /Mitigated Negative Declaration ICF 00914.11 <br />