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the potential for sleep.disturbance. -It establishes athreshold for a single event.for Which the-A-weighted sound exposure.level (ASEL) which occurs within a-room at 50 MA and not 65 dBA- as described in Me resort. ANS-1 procedure calculates elle probabilit.) I L ,of awakening based upon the men 9E and:the number of events which occur during the nightdfte hours {10:00 p.m. — 7:00 a m.). The ANSI procedure for estimating-the probability ofawakening:qalcul4tes a 97%probability of awakening,based upon an exterior SEL of 79 dRA and 182 truck trips during the highttihie period, as-indioaled in the BAC report. This is clearly a-major difference in the over-all analysis. The polefiii a'l f6rT82 heavy truck trips 'passing by at a distance 6 r 16ss.thari Wfeot from a residence duting a typical night, and not having-a major impact on steep disturbance does not pass the test of being an intuitively reasonable-analysis, D. The BAC report utilizes the noise measurement data a ryas at Sites A-and B to isolate the asphalt plant noise, levels. This process as used to determine the potential noise levels during ni&tfime operations. The roport concludes that the asphalt'plant noise level's will be between 35 and 45 dI3 Leq. First off, the n.oise. measurement locations do not accurately represent potential noise levels at the elevated residences. This is due to the fact that thel noise,MeasilreAnelit'SiteSL-Used for evaluating the asphalt plant operations were located-in depressions- In addition,since the noise ineasurement,data used to:-ex-tr4polqte the asphalt plant operations were due to.daytime asphalt plant operations,and Were,coll.eOted,at it distance of over 2,000 feet from the plant, the expected jaigi.ittinic noise bevels, due to'al-rnospheric conditions could increase by as much .as 5 4A to. 1.0 dBA, j,c. brerman &associates, Inc. staff have had first-hand experience in nieasurin.g industrial noise sources during the daytime and nighttime hours. It..has,been well documented that industrial noise-sources during the daytime hours.may. not even be audible at distances of 2,000 .feet.. I-lowcver, during the nighttime.hours;.the noise levels associated with these sources will increase by 10 dBA duo to latmospheric conditions. Therefore, we do not believe that the asphalt batch pWit noise. levels have accurately been identified. An accurate method for evaluating asphalt plant noise levels is to run the plant during- the nighttime hours, and collect noise level data during the operations. This would provide an accurate representation of potential noise impacts. At the very least, reference noise level measurements of the asphalt plant should have been conducted on the Munn Perkins site. These reference measurements could have been used to generate, noise contours associated with the operations. The noise-level data can be used as direct inputs into a model which can account for prevailing wind direction, wind rrt speed,temperature,atmospheric conditions and topography. C. The BAC report provides a discussion on "Optimization of Heavy Ttvck Operating Parameters to Minimize Passby Noise". This analysis provides good insight into the variations in operating conditions and how they affect the noise generated by the trucks. However, the education of individuals on the use 2