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13. Page 28 of the BAC report indicates that the analysis of truck noise impacts will assume that truck drivers are operating vehicles in the"quietest manner possible". This analysis does not appear to be a conservative approach to evaluating noise impacts. This would seem to indicate that there has been an identified significant impact,and that mitigation measures being implemented. 14.The analysis of sleep disturbance on pages 31 through 34 appears to be flawed. The American National Standards Institute (ANSI) has developed procedures for evaluating the potential for sleep disturbance. The Procedure ANSI/ASA S12.9-2008 / Part 6 sets the procedures for evaluating the potential for sleep disturbance. It establishes a threshold for a single event for which the A-weighted sound exposure level(ASEL)which occurs within a room at 50 dBA. The ANSI procedure calculates the probability of awakening based upon the interior mean SEL and the number of events which occur during the nighttime hours (10:00 p.m. — 7:00 a.m.). The BAC report indicates that there would only be a 5% probability of awakening. However,the ANSI procedure for estimating the probability of awakening calculates a 97% probability of awakening, based upon an exterior SEL of 79 dBA and 182 truck trips during the nighttime period, as indicated in the BAC report. This is clearly a major difference in the overall analysis. 15. Page 30 of the BAC report conducts an analysis of the "Traffic Noise Impacts Relative to County 65 dB Ldu Exterior Noise Standard". This analysis does not correctly address the County exterior noise level standard of 65 dB Ldn. The Ldn descriptor is a 24-hour average of all traffic noise. This analysis only evaluates the project traffic noise level. Although, later in the report, there is an evaluation of the over-all traffic noise, this analysis is misleading. A typical noise analysis for traffic noise impacts would first evaluate the existing traffic noise levels and compare them to the standard, and then evaluate the existing +project noise levels to show the comparison. The BAC report estimated the project-related truck trips to result in an Ldn of 63 dB at a distance of 60 feet. j.c. brennan & associates, Inc. utilized the Federal Highway Administration (FHWA PD77-108) traffic noise prediction model to evaluate the project-related truck traffic noise levels along E. River Road. The inputs assumed 248 total truck trips, with 66 of those trips occurring during the daytime hours. It assumed a speed of 40 mph (This is probably underestimating the actual travel speeds). The FHWA traffic noise prediction model resulted in an Ldn of 66 dBA. This would result in an exceedance of the San Joaquin County noise level criterion of 65 dB Ldn. 16.Page 30 of the BAC report conducts an analysis of the "Traffic Noise Impacts Relative to County 45 dB Ldn Interior Noise Standard". This analysis does not correctly address the County interior noise level standard of 45 dB Ldn. The Ldn descriptor is a 24-hour average of all traffic noise. This analysis only evaluates the project traffic noise level. Although, later in the report, there is an 7