ARCHIVED REPORTS_DRAFT ENVIRONMENTAL IMPACT REPORT

Home Browse Search

Section 17.13.030 specifies the point of measurement for both the noise and vibration standards. Measurements necessary for enforcement of performance standards shall be taken at the lot line of the establishment or use in any district, except in the M-1 and M-2 districts measurements shall be taken at the district boundary of 500 feet to the exterior wall of the establishment or use,whichever is less. 4.4.2 ENVIRONMENTAL IMPACTS ANALYSIS METHODOLOGY Noise-sensitive land uses and noise sources in the vicinity of the proposed project sites were identified based on existing documentation, aerial photos,and site reconnaissance data. To assess potential construction-noise and stationary-source noise impacts, sensitive receptors and their potential exposure, as a function of distance and ground cover,were identified. Typical noise levels associated with the specific types of construction equipment anticipated to be used for project construction were determined, and resultant potential noise levels at those receptors were calculated based on accepted relationships for noise attenuation. Potential vibration impacts were assessed according to methods recommended by FTA(FTA 2006). THRESHOLDS OF SIGNIFICANCE For the purpose of this analysis,the following applicable thresholds of significance, as identified by the State CEQA Guidelines (Appendix G), San Joaquin County, and the City of Manteca,have been used to determine whether implementing the proposed project would result in significant noise impacts. The proposed project would result in significant noise impacts if project implementation would do any of the following: ► Short-Term Construction Source Noise Levels. Short-term noise impacts would be significant if construction of the proposed project would expose persons to or generate noise levels in excess of applicable standards (e.g., City of Manteca and San Joaquin County general plan and municipal codes) or result in a substantial temporary or periodic increase in ambient noise above levels existing without the project(e.g., 5 dBA Ldn or greater) at nearby existing noise-sensitive receptors during the more noise-sensitive early morning, evening, and nighttime periods of the day(i.e., 7 p.m. to 7 a.m. in the City of Manteca and 9 p.m. to 6 a.m. in San Joaquin County). ► Long-Term Increases in Traffic Source Noise Levels. Long-term noise impacts would be significant if project-generated increases in traffic would expose persons to or generate noise levels in excess of applicable standards (e.g., City of Manteca and San Joaquin County general plans and municipal codes)or result in a permanent increase in ambient noise levels above levels existing without the project(e.g., 5 dBA Ldn or greater) at nearby existing noise-sensitive receptors. ► Long-Term Stationary-and Area-Source Noise Levels. Long-term noise impacts would be significant if project-generated stationary or area sources would expose persons to or generate noise levels in excess of applicable standards (e.g., City of Manteca and San Joaquin County general plans and municipal codes)or result in a permanent increase in ambient noise levels above levels existing without the project(e.g., 5 dBA Ldn or greater) at nearby existing noise-sensitive receptors. ► Compatibility of Proposed Land Uses with On-site Noise Levels. Long-term noise impacts would be significant if on-site noise levels would expose persons to or generate noise levels in excess of applicable standards (e.g., City of Manteca and San Joaquin County general plans and municipal codes) at proposed noise-sensitive receptors. ► Exposure of Sensitive Receptors to or Generation of Excessive Ground-Borne Vibration or Noise Levels. Vibration impacts would be significant if construction or operation of the proposed project would expose persons to or generate excessive groundborne vibration or groundborne noise levels(e.g., exceed EDAW Manteca WQCF and Collection System Master Plans EIR Noise 4.4-16 City of Manteca