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4, ENVIRONMENTAL ANALYSIS <br /> 4.6 AIR QUALrrY <br /> This analysis was completed in the same manner as for CO impacts and was completed to assess _ <br /> impacts along the truck haul routes. Using CALWFA, an annual DPM concentration was <br /> determined. First, assuming the peak hour trips occurs throughout the year(very conservative), <br /> the predicted DPM concentrations due to the Proposed Project would be 1.13 µg/m;and 0.482 w <br /> µg/m3 on an annual basis for Haul Route Options I and 2, respectively. Ambient DPM <br /> concentrations have been reported to range between 0.2 through 3.6µg/m3 depending on the <br /> location (urban vs.nonurban)(EPA, 2002). Using the DPM unit risk factor,as established by <br /> OEHHA,the maximum incremental carcinogenic risk is estimated to be 340 and 145 in a million <br /> for Haul Route Options 1 and 2,respectively. <br /> However,adjusting the hourly trips to an annualized average,the predicted DPM concentrations — <br /> due to the Proposed Project would be 0.216µg/m3 and 0.092 gg/m; on an annual basis for Haul <br /> Route Options 1 and 2,respectively. Using the DPM unit risk factor,as established by OEHHA, <br /> the maximum incremental carcinogenic risk is estimated to be 65 and 28 in a million for Haul <br /> Route Options 1 and 2,respectively. Thus,project-related and cumulative traffic would have a <br /> significant impact on local DPM concentrations within the Haul Route Options 1 and 2 _ <br /> scenarios. <br /> Mitigation Measure 4.6.6: Project DPM Impact of Haul Trucks. Retrofit non-road <br /> equipment engines with CARB-certified DPM filters and catalysts while using ULSD,when <br /> available. This would reduce DPM emissions from equipment by 85 percent. <br /> Implementation of ULSD and DPM filters on all haul trucks would reduce the carcinogenic _ <br /> risk to an estimated 9.72 and 4.13 cancers per million for Haul Route Options 1 and 2, <br /> respectively. <br /> Significance after Mitigation: By installing DPM filters on all haul trucks,impacts would be <br /> less-than-significant. However,this mitigation measure may not be feasible(i.e.,haul trucks not <br /> owned by project sponsor)and/or technically possible. Therefore,DPM impacts associated with <br /> haul truck generated by the project are considered significant and unavoidable. <br /> RMC Pacific Vemahs Quarry Mining and Reclamation Project 4.6-28 ESA/203015 ^ <br /> Administrative Draft EIR March 2004 <br />