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result in 26 hourly truck trips per hour during the nighttime hours. Based upon Table 7 of the BAC report, the average measured hourly background noise levels during the nighttime periods ranged between 59 dBA Leq and 62 dBA Leq at a distance of 60 feet from the centerline (Site 4). This corresponds with the closest building fariade to the roadway, as stated in the BAC report, if you use the lowest SEL value shown in the BAC report for truck passbys (79 dBA) at 60 feet, the Leq associated with the 26 trucks would be 62 dBA. Therefore, the nighttime noise levels would increase between 3 dBA and 4 dBA Leq. Based upon the F1CON criteria shown in Table 3 of the report, this would result in a significant increase in noise levels. What the analysis does not mention, is that the increase in noise levels which trigger a significant impact is based upon an increase in noise levels of the same character. So, if the ambient noise during the nighttime period is not a function of truck traffic, the increase in noise levels due to truck tragic could be more annoying than indicated. MITIGATION OPTIONS 19. Page 37 of the BAC report provides mitigation options. First of all we do not believe that the impacts have been adequately identified, and therefore,mitigation measures may not have been fully addressed. 20. The recommended mitigation measure for truck passbys seems unenforceable. Educating truck drivers on proper gear usage, speed and rpm of the engine is difficult to enforce,at best. 21. The mitigation measures indicate that upgrades to building facades is not recommended due to the fact that there would not be a significant impact associated with truck passbys. However, the ANSI procedure used by j.c. brennan & associates, Inc. indicates that the potential for sleep disturbance is 97%, which would indicate a significant impact. Building fagade upgrades would be a likely mitigation measure. A sound proofing analysis of the homes, conducted by an acoustical consultant would identify the appropriate upgrades to homes along East River Road. 22. There is no mention of mitigation for the asphalt plant. BAC staff have previously worked on an asphalt plant in Truckee California, where noise complaint resulted from nighttime operations. The installation of a silencer on the stack of the asphalt plant burner resulted in significant decreases in noise levels. 23.There is no mention of the use of strobes instead of back-up alarms on mobile equipment to reduce noise levels. 24.There is no mention of shielding of equipment through barriers or stockpiling of resource to reduce noise levels. 10