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Detailed Analysis The detailed analysis utilized the FHWA Traffic Noise Prediction Model and focused on the noise levels at specific receptors located along the five roadway segments passing the screening analysis discussed above.The detailed analysis included as inputs: ► the receptors' distance from the modeled road; ► the proposed widening of the road where applicable(Grant Line Road); and ► existing traffic conditions with and without implementation of the proposed projece.The effectiveness of any required noise barrier was also analyzed. Table 4.13-9 presents the predicted traffic noise levels at the property line of the existing sensitive noise receptors (residential)along the five roadway segments under existing and project conditions.Figure 4.13-2 shows the locations of sensitive receptors along the roadway segments that were the subject of the detailed analysis _ (identified by red squares and circled numbers in the figure). As shown by Table 4.13-9,the addition of College Park traffic to existing traffic volumes would not result in exceedance of the 65 dBA Ldn threshold and would not increase traffic noise by 3.0 dBA or greater at the existing noise-sensitive receptors along Byron Road,Mountain House Parkway,or the south side of Grant Line Road. In contrast, existing traffic noise levels could decrease along one or more of these roadway segments under the proposed project.Although this may seem counterintuitive, each of these roadways would be widened as part of the future roadway network under the MHMP(see Figure 4.11-11 in Section 4.11,"Transportation").This widening would distribute traffic to four rather than the existing two lanes of each of these roadways, thus decreasing existing traffic volumes in the travel lanes nearest the existing noise-sensitive receptors. See Section 4.11,"Transportation,"for further discussion. As indicated in Table 4.13-9,although the project would result in less-than-significant traffic noise impacts to existing noise-sensitive receptors along the majority of the roadway segments analyzed,project traffic would increase existing traffic noise at Receptor 14(the five existing homes on the north side of Grant Line Road, between Central Parkway and the Alameda County Line)by 3.57 dBA,from 65.54 dBA CNEL/Ld,to 69.11 dBA Ld./CNEL.This would represent a significant impact. Traffic noise impacts on existing noise-sensitive uses(impact analysis above)are determined based on existing traffic conditions with and without implementation of the proposed project.This is compared with traffic noise impacts on proposed noise-sensitive uses("Impact Analysis"under Impact 4.13-4),which are determined based on cumulative traffic conditions with and without implementation of the proposed project.Although Grant Line Village is an existing use,and thus subjected to the traffic noise analysis above,which is based on existing traffic — conditions with and without the proposed project,the residents of Grant Line Village raised concern about cumulative traffic noise impacts(i.e.,impacts of development of the College Park project combined with those of Specific Plans I and II along with other area growth)during the CEQA scoping meeting. Although cumulative noise impacts are evaluated in Chapter 6 of this Draft EIR, a detailed analysis of the cumulative traffic noise impacts on Grant Line Village is provided below in response to the comments received at the CEQA scoping meeting. 2 Traffic noise impacts on existing noise-sensitive uses are determined based on existing traffic conditions with and without _ implementation of the proposed project.This is compared with traffic noise impacts on proposed noise-sensitive uses that are determined based on cumulative traffic conditions with and without implementation of the proposed project. EDAW College Park at Mountain House Specific Plan III Draft EIR — Noise 4.13-22 San Joaquin County