SU0004657 - Laserfiche WebLink

Home Browse Search

r Dominant portions of all undisturbed habitat types exeept the annual grassland will not be disturbed. The blue oak woodlands type occupying some of the drainages will not experience d'istur- bance with the exception of some fringe elements which lie' above the- aggregate floor. The two manmade impoundments of greatest value to wildlife will also remain intact due to locations in major drainage floors which will not be excavated. Thus, ,habitat needs for species like the giant garter snake will be met throughout the quarry's life. Buffer zones on the permit perimeter and aqueduct will pro- r vide annual grassland habitat for the burrowing owl and other !, species should they move onto the permit area. Impacts are viewed as insignificant in consideration of the preceding factors and absence of sensitive animal species isight- ings. ight-Ings. 5.5 Noise A reconnaissance survey was performed to determine current j noise levels around the operating site and to indicate whether or not there were sites where noise at the property boundary ,;might have a significant impact. The date chosen was a Tuesday to i assure that the current facility was in normal operation. The { weather was calm with a high fog-condition that will allow the maximum travel for noise. The survey was performed by a licensed civil engineer using a Wartsila Type 7078 Integrating Sound Meter. ' Fifteen sites were monitored to obtain equivalent noise levels (Le on the weighted A-scale) . The sites were chosen to represent nearest residences, various sites around the plant, and property boundaries. At several sites, readings were taken facing the plant to obtain the maximum reading, and in a direc- tion facing away form the plant to obtain the minimum ambient reading. Results of the various measurements are presented in Table 5. 5. 1, and a map of the site locations is presented as Figure 5. As is evident, the ambient noise level is within the range of 30- 50 dB(A) . This is normally classified as Very Quiet to Quiet. The noise emanating from the mine and plant is audible atlthe property boundaries, but it ranges about 3-5 dB(A) . The only distinct sound is that from the mandated backup alarms installed on mobile equipment. Within the operating area, noise levels are about 50 dB adjacent ,to the office, and as high as 72 dB beneath the main screening plant. These higher noises within the plant operating site are equivalent to those measured along Brandt road and less than those measured at the crossing of Brandt Road and Clements Road some three miles to the West. No haul trucks were involved in the measuring with the exception of a single passing haul " truck negotiating the turn at the end of Brandt Road. this truck caused a reading of 70 dB(A) at a distance of about 70 feet. ' KRC Aggregate, Inc. - 6 - April 1, 1994