RES 06035 - Laserfiche WebLink

Chapter 4 Environmental Setting, Impacts, and Mitigation Measures J. Noise "normally acceptable" at a setback of 250 feet or farther from the center of Bernal Avenue. The potential Native American history reflective area (sub-area 14) is located more than 250 feet from the centerline of Bernal Avenue and noise levels would be less than 60 dBA Ldn. East of Valley Avenue (sub-areas 5, 3, and 2), unshielded noise levels would be 70 dBA Ldn at a distance of about 150 feet from the centerline of the roadway and noise levels would be 65 dBA Ldn at a distance of about 300 feet from the centerline of the roadway. The potential child-care facility (sub-area 5) would be shielded by the existing commercial uses at the southeast corner of Bernal Avenue and Valley Avenue. Without additional noise reduction techniques such as berms or barriers built along Bernal Avenue, noise levels at outdoor noise sensitive uses associated with the Bernal Community Park and the potential youth/community center (sub-area 2) would exceed those considered "normally acceptable" at distances of 300 feet or less from the center of the roadway. West of Pleasanton Avenue (sub-area 1), unshielded noise levels would be 70 dBA Ldn at a distance of about 90 feet or farther from the centerline of the roadway, 65 dBA Ldn at a distance of about 200 feet or farther from the centerline of the roadway, and 60 dBA Ldn at a distance of about 400 feet or farther from the centerline of the roadway. Depending on the design of the potential cultural arts center, some areas could be exposed to high noise levels. Without additional noise reduction techniques such as berms or barriers built along Bernal Avenue, noise levels at outdoor noise sensitive uses associated with the cultural arts center (sub-area 1) would exceed those considered "normally acceptable" at distances of 400 feet or less from the center of the roadway. Interior noise levels could also exceed 45 dBA Ldn. Valley Avenue. Based on traffic volumes supplied by Dowling Associates, Inc., planned areas would be exposed to traffic noise levels of about 70 dBA Ldn at a distance of 50 feet from the center of the roadway and about 65 dBA Ldn at a distance of about 100 feet from the center of the roadway. Potential land uses adjacent to Valley Avenue (sub-areas 2, 3, 5, 6, 7,8, and 9) include open space, trails, agriculture, Hearst Elementary School, and the pre- treatment marsh. The majority of these land uses would be considered compatible without addition noise reduction measures. However, the child care facility and Hearst Elementary School would be located in areas that would be considered to be "conditionally compatible." Interior noise levels could also exceed 45 dBA Ldn. Mitigation Measures Built Into the Specific Plan The following site planning and noise attenuation measures have been included in the Specific Plan to use when planning noise sensitive uses adjacent to noise sources to ensure noise and land use compatibility. . Noise levels at Hearst Elementary School (sub-area 8), the child care facilities (sub- area 5), and the cultural arts center (sub-area 1) should not exceed 60 dBA Ldn in outdoor noise sensitive areas and that interior noise levels do not exceed 45 dBA Ldn. A qualified acoustical consultant should be involved in the design of these noise sensitive uses to ensure compliance with the General Plan. 107