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URS .i attributed to some of the data acquired. The Micro-15 was used during the sampling activity on December 12-13, 2000 to acquire a better understanding of the noise levels acquired during noise generating activities and at some of the nearby receptors during those activities. The noise data collected was compared to the San Joaquin County Noise Element Standard and an assessment was made of the ability to meet that standard. In brief, the standard for day/night(7:00 a.m. to 10:00 p.m.) community noise level is set at an hourly equivalency of 50dBA with a maximum of 70 dBA. A 5dBA reduction in the standard is applied to noise that is due primarily due to speech or music. In evaluating the data, the 5dBA reduction was not included since it was not applicable to this agricultural use situation. The following sections describing the data results will be presented in two categories. The fust assessment sections will present the results of the hourly equivalency levels related to the 50dBA criteria level. The second discussion of the results will present the 70dBA maximum level. 50dBA Hourly Equivalent Data Results After assessing the data collected during the December 12, 2000 event (a total of 1,678 minutes sampled) it is evident from the 10-minute histogram for the percent time statistical distribution that 61.21% of the time (1,027 minutes out of 1,678 minutes) the 50dBA level was not exceeded. It should be further noted that 30.29%of the time (508 minutes out of 1,678) the sound pressure level was between 50dBA and 55dBA. The data indicates that approximately 5% of the time (84 minutes out of 1,678 minutes) measured between 55dBA and 60dBA. Correlating this data to the San Joaquin County "community noise element level (CNEL)" during the 7:00 a.m. to 10:00 p.m. period, it becomes evident that the average day-night level is approximately 53.56dBA. This figure includes the time for placement of the sampling equipment. If the sound pressure levels associated with the installation of the equipment are factored out,the resulting day- night level is 52.27dBA. A particular interest to the sampling event is the results from the 10:00 p.m. to 7:00 a.m. data, which indicates that an average night-day level is 52.78dBA with a factor correction for removal of the sampling equipment to 52.50dBA. According to the San Joaquin County Public Health and Safety Noise Element, Section IIID-1 of the General Plan dated July 1992 "... Various studies of community responses reveal the following implications of changes to ambient noise levels: • Except in carefully controlled laboratory experiments, an increase or decrease of only one dBA cannot be perceived, Noise Survey Report 2 Premier Environmental Services, Inc 01/31/01