5A Public Hearing 2019 0204 - Laserfiche WebLink

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3.0 ENVIRONMENTAL CHECKLIST 1388 Bancroft Avenue Project City of San Leandro Initial Study/Mitigated Negative Declaration November 2018 3.0-32 • Hayward fault (Southern Extension): 0.5 mile • Hayward fault (Northern Extension): 1 mile • Calaveras fault (North–South): 10.2 miles • San Andreas fault (Peninsula): 18.1 miles Moderate to severe earthquakes can cause strong ground shaking, which is the case for most sites in the Bay Area. A peak ground acceleration analysis was prepared, in accordance with the California Building Code, as detailed in Appendix GEO. Plans submitted in conjunction with building permit applications would be designed in accordance with the latest California Building Code requirements. The City would review and approve the plans as part of the standard building permit plan check process. In addition, mitigation measure MM GEO-1 would require the project applicant to incorporate the recommendations of the geotechnical report. With these measures, the potential for the proposed project to expose people to risk as a result of ground shaking would be less than significant. iii) Less Than Significant Impact with Mitigation Incorporated. The project site is within a State- designated Liquefaction Hazard Zone (Cornerstone 2016). The factors known to influence liquefaction potential include grain size, relative density, groundwater conditions, effective confining pressures, and intensity and duration of ground shaking. Loose, saturated, near- surface, cohesionless soils exhibit the highest liquefaction potential, while dense, cohesionless soils and cohesive soils exhibit low to negligible liquefaction potential. The geotechnical investigation primarily encountered stiff cohesive and dense granular soils below the groundwater level of 30 feet. Therefore, the site is considered to have low potential for liquefaction (Cornerstone 2016). As described above, the project applicant would be required to implement MM GEO-1, which includes measures to reduce or avoid the potential for significant impacts related to liquefaction. Therefore, this impact would be less than significant with mitigation incorporated. iv) Less Than Significant Impact. The project site is generally flat, there are no stream channels within 500 feet of the site, and the potential for liquefaction is considered low (Therefore, the potential for lateral spreading is also considered low (Cornerstone 2016). This impact would be less than significant. b) Less Than Significant Impact. The proposed project would replace existing structures and paved areas with new buildings, parking, landscaping, and open space. Excavation and grading could result in short-term erosion or loss of topsoil. However, project construction would not change the local topography and would not result in an increased potential for erosion. Because the project would disturb over 1 acre of land, the project applicant would be required to obtain coverage under the General Permit for Discharges of Storm Water Associated with Construction Activity (Construction General Permit Order 2009- 0009-DWQ or 2009-0009-DWQ General Permit) to comply with CWA National Pollutant Discharge Elimination System (NPDES) requirements. Compliance with these requirements would include preparation of a stormwater pollution prevention plan (SWPPP), which would specify best management practices (BMP) to quickly contain and clean up any accidental spills or leaks. In accordance with San Leandro Municipal Code Section 7-12- 230, the project applicant is required to prepare and implement an erosion and sedimentation control plan and a drainage plan. The plans would be required to include interim erosion and sedimentation control measures (such as containment structures or control devices) to be taken during the wet season until permanent erosion and sedimentation control measures can adequately minimize erosion, excessive stormwater