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Construction-related activities associated with the proposed WQCF, outfall, and collection systems would result <br /> in project-generated emissions of criteria air pollutants (e.g.,PMIo) and precursors(e.g.,ROG and NOx) from site <br /> preparation(e.g., excavation,grading,pavement breaking, and clearing); off-road equipment,material transport, <br /> and worker commute exhaust emissions;paving; application of architectural coatings; and other miscellaneous <br /> activities. <br /> Worst-case project-generated, construction-related emissions of criteria air pollutants and precursors were <br /> modeled in accordance with SJVAPCD-recommended methodologies (SJVAPCD 2002 and 2006a). Exact <br /> project-specific data(e.g., construction equipment types and number requirements, and maximum daily acreage <br /> disturbed)were not available at the time of this analysis. Project-generated emissions were modeled based on <br /> general information provided in the project description(Refer to Table 3-4), and default and SJVAPCD- <br /> recommended model settings and parameters attributable to the construction period and site location. In order to <br /> reasonably estimate worst-case conditions,project-generated emissions were modeled based on the following <br /> assumptions: <br /> ► Construction of the proposed project is anticipated to occur in two, 2-year phases; Phase 1 beginning in June <br /> 2008, and Phase 2 in June 2018 (Refer to Table 3-4); <br /> ► At the WQCF site, all grading would take place at the start of each 2-year phase. Extensive grading would not <br /> be required because all improvements would be within the existing site,which is relatively flat and clear. <br /> ► All of the wastewater collection system pipeline installation would occur within Phase 1. To achieve this, <br /> there would be three separate construction teams; one each for the north trunk sewer, south trunk sewer, and a <br /> third for the outfall and central trunk sewer. At an average installation rate of 100 to 125 feet per day,the <br /> north and south trunk sewers would take 2 years to complete. <br /> ► At an average installation rate of 100 feet per day,the outfall and central trunk sewer project would take 9 <br /> months to complete and is assumed to occur during Phase 1. <br /> Emissions of Ozone Precursors <br /> With respect to ozone precursors,worst-case project-generated,construction-related emissions of ROG and NOx <br /> were modeled using the URBEMIS 2002 Version 8.7 computer program as recommended by the SJVAPCD <br /> (SJVAPCD 2002 and 2006a)based on the assumptions outlined above. Table 4.3-6 summarizes the modeled <br /> emissions for each year of Phase 1 and Phase 2. Construction-related air quality effects were determined by <br /> comparing these modeling results with applicable SJVAPCD significance thresholds. Refer to Appendix B for <br /> detailed modeling input parameters and results. <br /> Table 4.3-6 <br /> Summary of Modeled Short-Term Project-Generated Emissions from <br /> Construction Equipment (Unmitigated) <br /> Phase/Year/Mode Worst-Case Emissions(Tons Per Year) <br /> ROG NOx PM101 <br /> Phase 1,Year 1 (2008-2009) <br /> WQCF 0.16 1.12 0.32 <br /> Collection System and Outfall 2.19 13.48 0.96 <br /> Total 2.35 14.60 1.28 <br /> Phase 1,Year 2(2009-2010) <br /> WQCF 0.28 0.73 0.03 <br /> Collection System 1.58 9.42 0.59 <br /> EDAW Manteca WQCF and Collection System Master Plans EIR <br /> Air Quality 4.3-20 City of Manteca <br />