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US level for approximately 60 minutes due to the use of fumigation equipment at a nearby orchard. It should also be noted that the largest piece of equipment at the site referred to as the "hydroseeder"was loaded and idled for five minutes within five feet of the meter before leaving the yard at 7:38 a.m. and registered a short-term reading of 67dBA. The readings collected during the delivery of material by the"18-wheeler" registered between 66-68dBA during the time when it was most active. A short term reading of 72dBA was recorded from the 18-wheeler at 2:15 p.m. when the truck was positioning to exit the driveway, shut trailer doors then stopped and idled less than 10 feet from the meter. Although the site was active throughout the day the only activity which resulted in reading between 70-79dBA was the use of a power washer that was used to clean trucks and equipment from approximately 5:20 p.m. to 5:50p.m. During the majority of the other activities at the site the background sound pressure level originating from State Route 99 was the dominating perceivable noise source. Conclusions and Recommendations It is clear that if attenuation strategies such as limit time of operation, limit of time deliveries and/or construction of a fence, mechanisms and structural features are properly addressed exceeding the 70dBA maximum level should be greatly reduced. Exceeding the 50dBA standard is likely to continue to occur and is expected given the higher ambient levels due to traffic noise from State Route 99. It is difficult to ascertain how the ambient or background noise can be brought into the hourly 50dBA or lower range to meet the CNEL standard specified in the San Joaquin Noise Element. According to the San Joaquin Public Health and Safety Noise Element, Section 4, Part III.D-8, "...The 1978 COG study estimated the number ofpeople who were exposed to noise levels greater than 60 dB. About 7% of the population resided in areas exposed to Ldn levels of 60-65dB. Considered conditionally acceptable according to State guidelines. About 12%of the population was exposed to noise levels of 65- 65(70)[sic]dB, again conditionally acceptable. Approximately 3%of the population resided in areas considered normally unacceptable for residential development, 70-74 dB. Finally, one-half of l% were found to live in noise exposure areas that were clearly unacceptable, 75dB or greater. The number of affected residents has certainly increased since 1975... " It is quite likely that the noise level increases from 1975 are indeed greater than the figures quoted in the COG study due to the increases in development and traffic in the area and the county must address these issues in a reassessment of the noise element. Noise Survey Report 5 Premier Environmental Services, Inc 01/31/01