EXHIBIT 4-1_55A_BRISTOL WIDENING EIS-EIR

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holidays) when noise intrusion is less disruptive. The local noise ordinance specifies which hours each day construction activities can occur. Federal Standards: The "Federal Highway Program Manual" (F— PM 7-7-3) requires that land use activities which may be affected by highway construction noise be identified. In addition, the measures needed in the plans and speci- fications to minimize or eliminate construction noise impacts must- be determined. However, no specific guidelines are available for assessing the significance of construction noise impacts. The 1981 California Standard Specifications Section 7- 1.0IN, Section 42 -1.02, and Section 42 -2.02 (as shown in the Appendix) and Standard Caltrans Special Provisions Section 5 -1 (Sound Control Requirements) may be referenced in the project plans and specifications when they apply to minimise or eliminate construction noise impacts. A diagram illustrating various construction noise control strategies developed by Caltrans is included on page 18 of the Appendix to the Technical Appendix. Long -Term Acoustic Impacts Daily traffic data for future conditions with and without the project was provided by Willdan Associates. The findings of the traffic study indicate that daily traffic volumes would not change with the proposed project versus the no- project alternative. However, traffic congestion along Bristol Street would decrease, and a consistent set of improvement standards would also improve safety and other operational characteristics. Future noise levels within the project area, expressed as contour lines at varying distances from the centerline of the roadway, were projected by employing the FHWA RD -77 -108 Highway Traffic Noise Prediction Model. Noise contours serve as a planning tool for local agencies to assist in future land use decisions on undeveloped sites and to help select sensitive receptor sites for analysis of traffic noise impacts. Noise emission levels were obtained from National Reference Energy Mean Emission Levels as a Function of Speed (per paragraph 14 of FHPM 7 -7 -3). The posted speed limit was assumed to be representative of future mid -block conditions with the proposed project and the no- project scenarios as a "worst case" assumption. A 2.58 percent truck mix was assumed along Bristol Street. City Standards: Table 16 shows the community noise equivalent levels which can be expected adjacent to each roadway link within the project area for design year (2006) conditions with the proposed project and the no- project alternative. As shown, future noise levels adjacent to Bristol Street will be higher with the proposed project than with the "no- build" alternative because of the wider pavement width. The increase would amount to 1 dBA or less. IV -23