SU0004094 - Laserfiche WebLink

Home Browse Search

4.Environmental Analysis - TABLE 4.5-5 - EXISTING AND PROJECTED MORNING PEAK-HOUR TRAFFIC NOISE LEVELS ALONG LOCAL ROADWAYS (dBA, Leq'-"-c) Cumulative Existing Plus Haul Route Plus Haul Route Segment Roadway Cumulative No. Segment Existing Opt.1 Opt.2 Opt.3 No Project Opt.1 Opt 2 Opt.3 - Koster Road south 1 63.9 76.4 76.4 76.4 70.0 of Blewett Road Blewett Road east - 2 58.8 58.8 58.8 77.1 65.4 65.4 65.4 77.3 of Koster Road 3 Welty Road north 64.6 64.6 64.6 76.4 66.8 66.8 66.8 76.6 of Blewett Road 4 Welty Road south 65.4 65.4 65.4 65.4 66.8 66.8 66.8 66.8 of Blewett Road Koster Road south 5 65.8 65.8 74.5 65.8 71.6 71.6 75.9 71.6 of State Route 132 State Route 132 6 east of Koster 75.6 76.4 76.4 76.4 83.2 83.3 83.3 83.3 Road State Route 132 7 west of Koster 75.4 76.1 77.1 76.1 83.2 83.3 83.5 83.3 Road Blewett Road east 8 68.9 77.7 75.0 66.9 73.7 78.7 76.8 73.7 of Bird Road Slate Route 33 9 west of Welty 66.9 NA NA 77.0 74.9 NA NA 78.8 Road ' Noise levels were calculated using the FHWA Traffic Noise Prediction Model for weekday morning peak-hour conditions during periods of maximum production.Noise levels were calculated at roughly 50 feet from the centerline of the roadway. ° The proportion of trucks and automobiles and their respective speeds differ for each of the modeled road segments based on the professional assumptions of Peters Engineenng Group and ESA. ` The Cumulative No Project scenario is based on Future No Project plus Granite Operation and the Cumulative Plus Haul Route - scenarios are based on Future No Project plus Granite Operation plus respective Haul Route traffic. Bold and underlined values show potentially significant noise increases prior to any mitigation.NA= Not Available. SOURCE: Environmental Science Associates,2006 To assess potential noise impacts,the project and cumulative scenarios are compared to existing _ conditions using Significance Criteria 1 and 2 (discussed above): 1. A 3 dBA DNL increase in noise as a result of project operations if the resulting level - exceeds the "normally acceptable range"for the land use(65 dBA DNL or less for residential development). 2. A 5 dBA DNL increase in noise as a result of project operations if the resulting level is within the"normally acceptable range"for the land use. In analyzing noise effects from the haul routes,the general rule is applied that in areas where - traffic dominates the noise environment, the L,during the peak-hour is roughly,equivalent (within about 2 dBA)to the DNL at that location. RMC Pacific Vernalis Quarry Mining and Reclamation Project 4.5-20 ESA/203015 Draft Environmental Impact Report May 2006