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Noise Criteria Used to Assess Impacts Associated with this Project Any noise impact analysis should consider where and when the noise-sensitivity of those potentially affected by a project exists. For this project, noise will be periodically generated by Munn & Perkins on-site equipment (asphalt plant) and off-site truck traffic during the hours of 9 p.m. to 5 a.m., as it historically has while servicing night paving projects. As noted previously, however, such operations would continue to occur only when nighttime paving projects require materials during these hours. One of the critical questions in terms of the noise impact analysis is where will the sensitivity of noise exist during those nighttime hours? It is reasonable to assume that noise-sensitivity at outdoor activity areas of the residences constructed within the project area will be severely limited, if it exists at all, during the nighttime hours which would be affected by the project. For example, it is highly unlikely that outdoor activities would be taking place between 1 a.m. and 3 a.m., the quietest measured hours, on nights when the facility would be operating due to a project's requirement for nighttime paving materials. Because the hours affected by the project are nighttime hours (with the exception of the 9 p.m. hour, which technically is considered daytime), it is equally reasonable to assume that the vast majority of the noise-sensitivity during those hours will be within bedrooms while residents are sleeping. In light of these reasonable assumptions regarding the realistic locations where and when project noise impacts would be likely to occur, the focus of this analysis is on noise impacts associated with sleep disturbance caused by the project. In light of recent findings that the potential for awakenings is less than 5% for interior SEL values of 65 dB or less, potential noise impacts are identified in cases where interior SEL values would exceed that level within bedrooms due to project traffic. Although there is likely very little (if any), nighttime sensitivity at the exterior areas of residences located along East River Road, the County's nighttime noise standards for outdoor activity areas of residential uses are nonetheless addressed in this assessment as well. Specifically, potential noise impacts are identified if the nighttime operation of on-site sources (i.e. those sources involved with the nighttime production of asphalt materials) would cause noise levels to exceed the County's 45 dB Leq and 65 dB Lmax noise standards at the exterior space of the nearest residential uses. Finally, because CEQA requires that impacts be considered if a project would result in either substantial short-term 1 temporary, or permanent, increases in ambient noise levels, this analysis provides an assessment of project-related noise increases using the FICON methodology identified in Table 4. Environmental Noise analysis Munn&Perkins Expanded Hours of Operations—San Joaquin County Page 10