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j.c. brennan & associates <br /> consultants in acoustics <br /> P.O. Box 6748 -Auburn,California 95604 <br /> 263 Nevada Street•Auburn,California 95603 <br /> p.530.823.0%0 - f.530A23.0961 - www jcbrennanassoc.cnm <br /> August 16, 2011 <br /> Mr.Tom Terpstra <br /> Law Office of Thomas H. Terpstra <br /> 578 N. Wilma Avenue, Suite A <br /> Ripon, CA 95366 <br /> Subject: Review of Munn& Perkins EIR <br /> Dear Mr. Terpstra: <br /> j.c. brennan & associates, Inc. has reviewed the Noise Section of the Draft EIR for the 1-22 <br /> above referenced project. The Noise Section utilizes both the Bollard Acoustical <br /> Consultants (BAC) technical noise analysis, and the peer review/comments we have <br /> previously provided on the BAC study. <br /> Comment 1. <br /> The EIR utilizes noise level data previously collected by BAC in 2008 to characterize the <br /> ambient noise environment. The noise measurement data collected by BAC continues to <br /> be suspect,when characterizing noise levels associated with the batch plant at the nearest <br /> residences to the east. The BAC report utilizes the noise measurement data collected at <br /> Sites A and B to isolate the asphalt plant noise levels. This process was used to <br /> determine the potential noise levels during nighttime operations. The report concludes <br /> that the asphalt plant noise levels will be between 35 and 45 dB Leq. First off, the noise <br /> measurement locations do not accurately represent potential noise levels at the elevated <br /> residences. This is due to the fact that the noise measurement sites used for evaluating 1-23 <br /> the asphalt plant operations were located in depressions. <br /> In addition, since the noise measurement data used to extrapolate the asphalt plant <br /> operations were due to daytime asphalt plant operations, and were collected at a distance <br /> of over 2,000 feet from the plant, the expected nighttime noise levels, due to atmospheric <br /> conditions could increase by as much as 5 dBA to 10 dBA. It has been well docurnented <br /> that industrial noise sources during the daytime hours may not even be audible at <br /> distances of 2,000 feet. However, during the nighttime hours,the noise levels associated <br /> with these sources may very well increase by as much as 10 dBA due to atmospheric <br /> conditions. Therefore, we do not believe that the asphalt batch plant noise levels have <br /> accurately been identified. An accurate method for evaluating asphalt plant noise levels <br /> is to run the plant during the nighttime hours, and collect noise level data during the <br /> operations. This would provide an accurate representation of potential noise impacts. At <br /> 1 <br />