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The Table 5 data indicate that ambient noise conditions at the measurement sites varied, with average existing noise levels generally near or below the County's daytime and nighttime average (Leq) noise level thresholds of 50 dB Leq and 45 dB Leq, respectively, and computed Ldn values well below the County's 60 dB Ldn standard applied to residential uses. A notable exception is the data collected on October 2, 2008, in which the daytime ambient noise environment is believed to have been heavily influenced by almond harvesting activities. Average and maximum noise levels registered during the afternoon of October 2 were considerably higher than those collected during the other days of the sample. In fact, inspection _ of Appendices B-6 and B-12 reveals that local almond harvesting activities likely occurred during the noon to 5 pm hours, dramatically affecting the noise measurement results for that day. Because the data collected during the apparent almond harvesting activities near the noise �- monitoring sites is clearly anomalous, average and maximum daytime noise levels for October 2 were recalculated with the noise levels measured during those hours omitted. The recalculated noise levels for that day are included as the last rows of data for each site in Table 5. With respect to measured Leq values for individual hours during which the Munn & Perkins asphalt plant was operating (not averages for the complete daytime or nighttime periods), the Appendix B data indicate that noise levels varied. For example, on Sunday, September 28'h 2008, the Munn & Perkins asphalt plant operated during the hours of 7 am through 2 pm. Because these operations occurred during daytime hours (7 am — 10 pm), the average (Leq) and maximum (Lmax) noise level standards applicable to these operations at the nearest residences are 50 dB Leq and 70 dB Lmax. Examination of Appendix B-2, which contains the complete listing of noise measurement data for September 28'r' at measurement Site "A", as well as a visual indication of when the asphalt plant was in operation, reveals that average noise levels during the period during which the plant was operating ranged from 40 to 46 dB Leq. This range of noise levels is below the County's 50 dB Leq standard. In addition, measured maximum noise levels during that same period ranged from 49 to 62 dB Lmax during this period. also below the daytime 70 dB Lmax standard of the County. A similar finding of compliance w0 the County noise standards was made for this day of operations (September 28"') at noise measurement Site B with the exception of the 2 pm hour, during which time a clearly anomalous event resulted in an elevated Leq of 56 dB. This information pertaining to noise levels measured during individual hours on this Sunday is critically important because Sunday's are typically the quietest days of the week due to reduced traffic and human activity. Because the Munn & Perkins asphalt plant operations, which generate steady-state noise levels while the plant equipment is operating, satisfied the County's requirements on this Sunday period of low ambient conditions, it is reasonable to conclude that during periods when the County's noise level standards were exceeded during asphalt plant operation, those exceedances were caused by other local ambient noise sources and not the Munn & Perkins asphalt plant Environmental Norse Anafysis Munn&Perkins Expanded Hours of Operations— San Joaquin County Page 13