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3. Response to Comments Bollard Acoustical Consultants.. Inc. (BAC) has completed SOLMOLAN modeling,of the project asphalt plant. Project asphalt plant noise contours are a result of this modeling effort. These contours are presented in BAC's report of September 1. 2011. The noise contours support BAC's noise level measunmellts/arlalysis that project asphalt plant noise exposure does not exceed the applicable 5 dB L ,l criterion at the closest residential receivers. The September 1, 201 l BAC report has been included as Appendix A of the Filial EIR. Response to Comment 1-27: The cclnunentel-questions the feasibility of the proposed "optimization of Ileavy trLlck operating pararimer-, to r111111i11rze passbY noise. It has been shown throw-h controlled measurements conducted by Bollard Acoustical Consultants. Inc. (BAC)that an avera0e noise level reduction of 4 dB (SEI_ per truck passby) call be provided by iniplellicat111g the proposed operating parameters. I hese parameters iticlude speeds of`38-43 mph at 700-800 rpm in 8`l` sear %lien arriving to the site empty, and speeds bclov, ')3-=5 mph at 1600-1800 rpn1 in 61' or 7"' gear. We agree with Both BAC and J.C. Brennan & Associates that these IlleaSUI-CS %Ould be difficult to enforcc, budge also agree Nvlth BAC that cvery noise level l'ednCt1011 MeaSllre had al *,first tlille." alld 1Llst becallse it i111`?Ilt 11C ClrffiClllt to ellforCe/t"COLllalte and maintain_ does not make it unreasonable or infeasible. At one point, noise-mitigating aircraft departure procedures at major U.S. airports (e.g., John Wayne Airport, Orange County) %'ere Clnestloned for the saline reasons. belt now benefit the CO111111L1111tieS around them. With appropriate t:dueatlon and enforceIllcnt, the: provided mitigation measure would be expected to benefit the residents on East River Road near the project site. Response to Comment 1-28: The commenter addresses the Methodology used ire the "probability of awakening" analysis %pilin the Bollard Acoustical ConSultants. [tic. (BAC) report of August 23, 2010. Atter aceept.in) that the project DEIR has utilized the ANSIIASA S 12.9-2008/Part 6 methodology for assessing probability of arvakenin�,z from p1-ojOct truck passbys.. the comincnter questions the reference noise level assumed for automobile passbys oil East River Road (i.e., at 60 feet. 75 dB SEI.. for autos compared to 83 dB SEL for heavy trucks) and the comparison of noise exposure front passing Milos relative to passing heavy trucks due to the different frequency content of the sources. First_ the pro?jeet DLI 1Z noise section does clot implement the FWAN sleep disturbance criteria implemented by BAC in their report of August 23. 2010. Instead, the DEIR has implemented the ANSI/ASA 512.9 methodolo4py to assess the probability of awakening duc to project truck passbys on East River Road. Its this case, art increase in the probability of 5% relative to the "no project" condition %as deemed significant. The reference noise exposure level ol'75 dB SEL I'm- automobile passbys was 1llcasured by BAC in 2008 during, their ambient noise measurement surveys in the project area. In their rllerllo of October 22, 2010, BAC refers to this noise level as a -conservative"estimate of single-event traffic (auto) noise exposure. For passenger cars/trucks tlavelin�T 55 mph an t1 rural raaclwtl}, this single-event noise exposure level is reasonable. Additionally_ this level is 8 dB lover than the level measltred/assurlicd for heavy truck passbys at -__-- Munn&Perkins Quarry Excavatio:r Permit 3-15 ESA 1 2110E3C, Final Envircnmental lMpad Report September 2011