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associated with such development includes that from air conditioning equipment,voices,and amplified music.
<br /> New residential uses under the proposed project would result in only minor increases in ambient noise levels,
<br /> primarily during the day and evening hours and less frequently at night, as perceived at the closest residential
<br /> receptors.Noise levels generated by stationary sources,primarily residential central air conditioning units,
<br /> averages approximately 60 dBA at 3 feet from the source(EPA 1971).Assuming a traditional side yard minimum
<br /> setback of 5 feet,noise levels generated by air conditioning units could exceed the MHMP daytime and nighttime _
<br /> noise standards of 55 dBA Ley and 50 dBA Ley,respectively,on adjacent residential properties.However,because
<br /> noise generated by residential air conditioning units is exempt from the noise standards for non-transportation
<br /> noise sources,this impact would be less than significant.
<br /> Commercial, Office, and Industrial Uses
<br /> The proposed project includes plans for the development of neighborhood commercial,office commercial,and
<br /> limited industrial uses on a total of 104.8 acres(Figure 3-6b). Potential sources of noise associated with these
<br /> types of land uses can vary substantially.Noise associated with office uses is typically limited to occasional
<br /> parking-lot-related noise(e.g.,opening and closing of vehicle doors,people talking)and would not result in an -
<br /> exceedance of the MHMP thresholds. Commercial and limited industrial land uses,however, often include
<br /> loading docks where noise from idling trucks,vehicle backup alarms,decompression of trailer track brakes,
<br /> forklifts,and other loading and unloading activities can reach maximum levels of approximately 90 dBA at 50
<br /> feet from the source(EPA 1971). Although these levels would be intermittent and not sustained for extended
<br /> periods such that they would exceed the hourly Ley thresholds of the MHMP,they could result in increased sleep
<br /> disruption to nearby residential dwellings during nighttime hours.In addition, some commercial uses may also
<br /> include operational processes that use outdoor equipment that can emit noise levels that would exceed the MHMP
<br /> hourly Ley thresholds.For instance,a backup generator producing 70 dBA Ley at a distance of 50 feet would
<br /> exceed MHMP's daytime threshold of 55 dBA Leq at residences within 300 feet, and MHMP's nighttime
<br /> threshold of 50 dBA Leq at dwellings within 500 feet.A significant impact could occur.
<br /> School, Community College, Neighborhood Park, and Community Park Uses
<br /> Noise typically associated with schools,college campuses,neighborhood parks,and community parks includes
<br /> the voices of adults and children,group recreation,and the opening and closing of vehicle doors in parking lots.
<br /> During periods when children, students,and community members are using exterior recreational areas, exterior _
<br /> noise levels can exceed 60 dBA Leq at 50 feet(EDAW 2001).Noise sources commonly associated with these
<br /> types of events include elevated voices from crowds and exterior public address systems. Noise levels typically
<br /> associated with recreational events, including noise from spectators and players,can reach approximately 75 dBA
<br /> L.at 50 feet (EDAW 2001).Hourly Leq sound levels would attenuate to a level below MHMP's daytime
<br /> threshold of 55 dBA Leq at a distance of 90 feet and below the nighttime threshold of 50 dBA Leq at a distance of
<br /> 160 feet. At the proposed community park,where night lighting would be provided at the athletic fields and the
<br /> skate park,these noise levels could extend into evening and nighttime hours.
<br /> The proposed project would include the development of two elementary schools,a community college,two
<br /> neighborhood parks,and a community park. As indicated in Figure 3-6b,most of the proposed school,community
<br /> college, and park development would be developed internal to the project site and/or away from existing land
<br /> uses. However,there are some exceptions:
<br /> the proposed schools and one neighborhood park would be developed across the street from the four existing
<br /> residences located in the center of the project site;
<br /> one proposed neighborhood park would be developed adjacent to Grant Line Village; and
<br /> the proposed schools,community college, and parks would be developed adjacent to or across the street from
<br /> proposed residential uses.
<br /> EDAW College Park at Mountain House Specific Plan III Draft EIR
<br /> Noise 4.13-18 San Joaquin County
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