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Table 2 <br /> Unmitigated Mining Equipment Noise Levels <br /> DeSilva Gates Quarry Project - San Joaquin County <br /> Combined Standard <br /> Day/Night <br /> — <br /> Reference Level at 50 ft. 80 N/A <br /> Receiver <br /> NI 47 60/57 <br /> N2 47 60/57 <br /> N3 50 60/57 <br /> N5 53 60/57 <br /> N6 38 60/57 <br /> N7 41 60/57 <br /> N8 41 60/57 <br /> r. W 1 46 50/45 <br /> W2 45 50/45 <br /> W3 47 50/45 <br /> E1 54 50/45 <br /> _ Notes: <br /> 1. Reference level from BAC measurements of similar sized quarries. <br /> 2. Distances from noise sources to receivers were scaled from project site plans and aerial photographs. <br /> .. 3. Levels were projected using 6 dB decrease per doubling of distance from reference location with additional <br /> -1.5 dB attenuation for atmospheric absorption and excess ground attenuation. <br /> 4. Noise standards for residences north of SR 132 are higher than those further south due to elevated <br /> ambient conditions north of SR 132. Please see discussion under standards of significance. <br /> 5. a-5 dB offset was applied to the mining levels to account for shielding provided by the proposed berms <br /> (10 feet)and existing canal embankment(15 feet). <br /> 6. Numbers marked as bold/underline represent exceedances of the day and/or nighttime standards <br /> established for this project. <br /> The Table 2 data indicate that mining related noise levels are predicted to satisfy the project <br /> standards of significance at all nearby residences during daytime hours with the exception of E1, <br /> _ but that the standards could be exceeded at 3locations during nighttime hours. Without additional <br /> mitigation,this would constitute a significant noise impact. Specific noise mitigation measures for <br /> mining operations are provided in a subsequent section of this report. <br /> — <br /> Page -5- <br />