SU0007300 - Laserfiche WebLink

Home Browse Search

The introduction of haul trucks vs. automobiles is a completely different noise source. The frequency content (low rumble) of trucks vs. the tire-on-pavement higher frequency content of an automobile is distinctly different. Based upon the Appendix C I of the Draft EIR, the existing roadway traffic volumes along East River Road during the nighttime hours is as little as 3 automobiles between the hours of 1:00 a.m. and 2:00 am. The project is expected to result in one haul truck passby every two minutes during that period. Even with the proposed mitigation, background hourly noise levels are still expected to increase by over 10 dBA. Generally, CEQA considers a significant increase in noise to be 3 dBA. Lets not forget that the mitigation was supposed to be implemented during the temporary permit in August 2011. The noise measurement results did not support that the mitigation was effective. Overall Reporting of Noise Impacts I think that it is interesting that the original noise analysis indicated that the noise levels from the asphalt plant would be as low as 35 dBA Leq during operations, based upon noise measurement data collected by Bollard. Now, as the process has continued, the predicted noise levels are equal to the nighttime standard of 45 dBA I.eq. However, no noise measurements have ever been conducted by Bollard at the Adrienne residence. The j.c. brennan data indicates that noise levels from the batch plant could be as high as 55 dBA Leq, and is consistently above 45 dBA Leq. It is also interesting that the original analysis by Bollard estimated the sleep disturbance to be approximately 5% to 10% using an antiquated method for calculating the potential for sleep disturbance. This analysis was used even though Bollard was fully aware of the more recent research in calculating sleep disturbance. Now the EIR states that there is a 99% to 100% chance for sleep disturbance or potential for awakening. However, the conclusions are still misleading, due to the fact that they assume that the majority of people are awakening due to existing traffic and that the trucks (1 every 2 minutes) will not significantly affect the potential for awakening. If you or the county staff has questions,please contact me. Respectfully submitted, j.c. brennan &,associates, Inc. sident Member: Institute of Noise Control Engineering file: 2011-148 Munn Perkins-February 2012 - VI 3