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northeast of Phase IV. The resulting, maximum exterior noise levels are estimated to be 61 dBA Leq (71 - 10) at residence R3 and 55 dBA Leq (55- 0) at residences Ra and R2 (earthen berms ofsufficient height already appear to be in place to protect these residences). Solid fences approximately 8 feet in height along the exposed property boundary would be expected to attenuate noise generated by surface-level mining by an additional 5 to 8 dBA in outdoor activity areas. The solid fences would block views in some directions and could potentially affect views of the Coastal Range Mountains from residences R4 and R5. However, these homes are oriented away from these views now and any impact would be less than significant because of the minor overall change that the fences would have in the context of the large,fat area that defines the project site and surrounding vicinity. The solid fences would not obstruct or substantially impair views of the Coastal Range Mountains and the San Joaquin Valley (see Impact 4.12.1). Mitigation Measures 4.5.1 a-d are feasible noise reduction measures that can be implemented for the project. It is likely that noise levels could still exceed the San Joaquin County Development Title daytime Leq standard of 50 dBA at the exterior property line of the three residences nearest to the project site (R3, R4, and R5)for a short period of time until mining moves deeper or further away from the residences. Thus the noise impact of the project would remain significant and unavoidable at these residences. Based on the whole record, the Board finds there are no additional feasible mitigation measures available to further reduce this impact to ambient noise levels at the nearest residence(s). This impact is therefore considered significant and unavoidable. (Draft EIR,pp. 4.5-16 to 4.5-17.) Impact 4.5.3 Traffic associated with operation of the project would result in an increase in ambient noise levels on nearby roadways used to access the mine. (Draft EIR, p. 4.5-19.) Significance Before Mitigation: Potentially Significant Facts: Cumulative traffic in combination with the project would increase noise levels haul routes. See Draft EIR,pp. 4.5-19 to 4.5-22. Mitigation Measures: Mitigation Measure 4.5.3: Depending on the selected Haul Route Option, the Applicant shall notify the homeowners(located along the roadway segments that would experience significant traffic-related noise)of the noise impacts associated with traffic from project operations. At the request of homeowners along the affected segments (limited to a reasonable number of complaints as determined by the County and not to exceed one year), the Applicant shall retain a qualified acoustical consultant to evaluate outdoor activity area and interior noise levels to determine if roadway traffic associated with the project is resulting in exterior noise levels that exceed 65 dBA DNL or interior noise levels that exceed 45 dBA DNL(the exterior and interior noise level standards contained in the San Joaquin County Development Title,respectively). For interior noise measurements, residences with air-conditioning units will be evaluated with 33