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Hacienda Mixed Use Rezoning Initial Study Less Than Potentially Significant with Less Than No Significant Mitigation Significant Impact Impact Incorporation Impact 11. Noise Would the project result in: a) Exposure of persons to or generation of noise levels in X excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies? b) Exposure of persons to or generation of excessive X groundbome vibration or groundbome noise levels? c) A substantial permanent increase in ambient noise levels X in the project vicinity above levels existing without the project? d) A substantial temporary or periodic increase in ambient X noise levels in the project vicinity above levels existing without the project? e) For a project located within an airport land use plan or, X where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project expose people residing or working in the project area to excessive noise levels? 0 For a project within the vicinity of a private airstrip, would X the project expose people residing or working in the project area to excessive noise levels? Environmental Setting The Noise Element of Pleasanton's General Plan incorporates State noise land -use compatibility guidelines for various land uses. The noise goal for noise sensitive land uses including residential development is an interior noise level of 45 L. L accounts for the difference in response of people to daytime and nighttime noises by weighting the noise decibels generated during the nighttime when background noise is generally less and people are more sensitive to noise events. To compensate for people's increased sensitivity during nighttime hours, the L measurement multiplies each nighttime noise event by a factor of ten, approximately equal to a doubling in perceived loudness. Existing noise levels around the project site derive mainly from vehicular sources on I -580, including BART, and vehicle traffic on roadways within Hacienda. Figure 11 -2 of the 2005 -2025 General Plan (Future (2025) Noise Contours) shows outdoor noise levels at the more northerly sites in excess of 70 dBA. Regarding airport noise, all three project sites are located more than 2 miles from the Livermore Airport. Significance Criteria The impact questions above constitute the significance criteria for this environmental topic. Discussion of Checklist Items Less than Signific Impacts The Pleasanton Municipal Code limits construction- related noise from any one piece of equipment to 83 dBA with up to 86 dBA total. Note that such noise levels would be sporadir rather than— continuous -in- nature because diff erenttypes- o ¢eonstruction equipment would be used throughout the construction process. As the receptor moves away from the noise source, the rate Draft, Subject to Revision 20 8/31/2009