ARCHIVED REPORTS_DRAFT ENVIRONMENTAL IMPACT REPORT

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the existing roadways where the trunk sewers would be installed,the principal noise source is vehicle traffic on adjacent roadways. Some of the roadways where sewers would be installed are currently rarely used or may not exist. In these areas,noise from agricultural equipment and aircraft overflight may be as noticeable as vehicle noise. The UPRR mainline track runs diagonally through Manteca in a southeast-to-northwest direction. There are about 18-23 freight trains on the track per day(City of Manteca 2003a).Noise from railroad operations (e.g,train pass-bys and warning horns) is also a dominant noise source for receptors near the tracks. The UPRR is also considered to be a source of groundborne vibration in the immediate vicinity of the tracks. REGULATORY SETTING Federal Plans, Policies, Regulations, and Laws The Federal Highway Administration(FHWA),the Federal Aviation Administration(FAA),and the U.S. Department of Housing and Urban Development(HUD)provide standards for noise levels in relation to highway projects, aircraft standards, and federally funded housing,respectively.None of these standards are relevant to this project. U.S. Department of Transportation To address the human response to groundborne vibration,the U.S. Department of Transportation(DOT),FTA has set forth guidelines for maximum-acceptable vibration criteria for different types of land uses. These include 65 VdB referenced to 1 gin/sec and based on the RMS velocity amplitude for land uses where low ambient vibration is essential for interior operations(e.g.,hospitals,high-tech manufacturing, laboratory facilities); 80 VdB for residential uses and buildings where people normally sleep; and 83 VdB for institutional land uses with primarily daytime operations (e.g., schools,churches, clinics, offices) (FTA 2006). Standards have also been established to address the potential for groundborne vibration to cause structural damage to buildings. These standards were developed by the Committee of Hearing,Bio Acoustics, and Bio Mechanics (CHABA)at the request of the U.S. Environmental Protection Agency(FTA 2006). For fragile structures, CHABA recommends a maximum limit of 0.25 inch per second(in/sec)PPV(FTA 2006). State Plans, Policies, Regulations, and Laws Governor's Office of Planning and Research The State of California Governor's Office of Planning and Research(OPR)published the State of California General Plan Guidelines(OPR 2003),which provide guidance for the acceptability of projects within specific day-night average noise level(Ld„) contours. Table 4.4-3 summarizes acceptable and unacceptable community noise exposure limits for various land use categories. Generally,residential uses (e.g.,mobile homes)are considered to be acceptable in areas where exterior noise levels do not exceed 60 dBA Ld,,. Residential uses are normally unacceptable in areas exceeding 70 dBA Ldn and conditionally acceptable within 55-70 dBA Ldn- Schools are normally acceptable in areas up to 70 dBA Ldn and normally unacceptable in areas exceeding 70 dBA Ldn. Commercial uses are normally acceptable in areas up to 70 dBA CNEL. Between 67.5 and 77.5 dBA Ld,,, commercial uses are conditionally acceptable, depending on the noise insulation features and the noise reduction requirements. The guidelines also present adjustment factors that may be used to arrive at noise acceptability standards that reflect the noise control goals of the community,the particular community's sensitivity to noise, and the community's assessment of the relative importance of noise pollution. Table 4.4-3 Summary of Land Use Noise Compatibility Guidelines Land Use Category Community Noise Exposure(dBA Ldn) Manteca WQCF and Collection System Master Plans EIR EDAW City of Manteca 4.4-7 Noise