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7.A. - Page 216 Pete's Harbor City of Redwood City EIR Addendum October 8, 2012 Page 3-53 3.10 NOISE The relationships of the current Pete's Harbor project to the 2003 EIR noise impact and mitigation conclusions are described below. Impact 13-1 Analysis: Project Compatibility with the Existing and Projected Noise Environment. The 2003 EIR indicated that residences on the uppermost stories of the project towers (up to 23 stories in height) would not be shielded from distant noise sources (e.g., U.S. 101 and aviation traffic), resulting in projected noise levels exceeding standards identified in the City's General Plan Noise Elementand in the San Carlos Airport Land Use Plan (ALUP). The associated 2003 EIR mitigation required an acoustical study for the multifamily residential component of the project in accordance with State Title 24 requirements, and implementation of measures (e.g., insulation, forced-air mechanical ventilation, sound-rated windows) sufficient to maintain interior noise levels at or below City and State standards (45Ld�)• Although the current Pete's Harbor project would reduce the project's maximum building height from 260 feet (23 stories) to 70 feet (5 stories), the multi-story residential wraparound building (see Figures 2.12 and 2.13) would still be the tallest building in the vicinity and, thus, would still not be shielded from distant noise sources. Impact 13-1 continues to apply to the current project. Conclusion. Modified impact and mitigation. The impact and mitigation have been modified to apply specifically to the current Pete's Harbor project. Mitigation 13-1, as modified, remains applicable to the current Pete's Harbor project and remains sufficient to reduce this impact to a less-than-significant level. Impact 13-2 Analysis: Ground-Borne Vibration Levels. According to the 2003 EIR, project construction would involve the driving of piles up to 95 feet in length (and potentially longer, depending on project final design and engineering), which could result in structural damage and interference with daily activities in the vicinity. The associated 2003 EIR identified mitigation included the following noise abatement measures: (1) restrictions on the hours of vibration- generating construction, (2) written notification of the construction schedule to nearby occupants, and (3) use of pre-drilled pile holes. Both the previous Marina Shores Village project and the current Pete's Harbor project would require building foundations supported on piles. However, since the current project proposes a reduction in building heights and a reduced project size compared to the previous project, the current Pete's Harbor project is expected to utilize auger cast piles, whose installation is typically substantially less noisy than driven piles. Although the potential pile-related vibration impact would be reduced accordingly, the impact conditions described in Impact 13-2 would still apply. Conclusion. Modified impact and mitigation. Because pile driving would be replaced with auger cast pile installation, Mitigation 13-2 has now been modified accordingly. The mitigation remains sufficient to reduce this impact to a less-than-significant level. Impact 13-3 Analysis: Project Demolition and Construction Noise. Project demolition and construction activities would temporarily elevate noise levels at adjacent residential areas (e.g., from Villas at Bair Island, Marina Pointe) as well as at on-site project residences constructed and inhabited during early phases of project construction. Although the current Pete's Harbor T.•1106951Addenduml3(10695-01).doc