AgdaPkt 2013-09-09 - Laserfiche WebLink

Browse Search

a,7.A. - Page 29 Finding: Implementation of Mitigation 15-2 would reduce these potential groundwater impacts to a less-than-significant level. Facts in Support of Finding: Implementation of Mitigation 15-2 would reduce potential high groundwater impacts to a less-than-significant level by requiring detailed, site- specific geotechnical investigations and solutions prepared by a registered engineering geologist or geotechnical engineer, with review and approval authority by the City Engineer. These facts are described in Draft EIR chapter 15 (Geology and Soils) on pages 15-1 through 15-15, which is hereby incorporated by reference. Impact: Impact 15-3: Soil Erosion. Project development would disturb the site's existing cover of buildings, pavements and landscaping, potentially leaving soils exposed to wind and water erosion during the construction period. Eroded soils would be washed into on-site drainage facilities that discharge to the Bayfront Canal and San Francisco Bay. Deposition of these soils through natural sedimentation could adversely affect the carrying capacity of drain lines, pumping equipment and open channels, increasing flooding potential and maintenance requirements. In addition, suspended sediment would degrade water quality in the canal and in the bay by increasing turbidity levels. Mitigation: Mitigation 15-3. The applicant shall develop an erosion control plan in accordance with the provisions of the project's City-approved Stormwater Pollution Prevention Plan (SWPPP). The erosion control plan would be implemented throughout project construction, and would include measures for the post-construction stabilization of all disturbed ground. Finding: Implementation of Mitigation 15-3 would reduce these potential soil erosion impacts to a less-than-significant level. Facts in Support of Finding: Implementation of Mitigation 15-3 would reduce potential soil erosion impacts to a less-than-significant level by requiring detailed, site-specific geotechnical investigations and solutions prepared by a registered engineering geologist or geotechnical engineer, with review and approval authority by the City Engineer. These facts are described in Draft EIR chapter 15 (Geology and Soils) on pages 15-1 through 15-15, which is hereby incorporated by reference. Impact: Impact 15-4: Settlement and Foundation Movement. The project's preliminary geotechnical studies determined that structural loads imposed by buildings more than approximately three stories in height would likely exceed the bearing capacity of either fill or weakly consolidated Bay mud underlying conventional shallow foundations. Such buildings would potentially experience gradual but excessive long-term total and differential settlements. Mitigation: Mitigation 15-4. The detailed, design-level geotechnical investigations required under Mitigation 15-1 for each project construction phase shall include a thickness and consolidation analysis of all clay soils underlying proposed building locations. This analysis shall be sufficient to accurately estimate the rate and total amount of consolidation expected to occur in response to building construction, as well as the likely magnitude of differential settlement. Building ATTY/RES0.2901/STANFORD EIR CERTIFICATION REV:08-29-13 VR Page 19 of 56