Reso 2020-119 1388 Bancroft Apartments MND MMRP

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3.0 ENVIRONMENTAL CHECKLIST runoff, and sedimentation (containment structures, overhead coverage, control devices). With required implementation of these plans and BMPs, substantial erosion or the loss of topsoil would not occur at the project site. Impacts would be less than significant. c) Less Than Significant Impact with Mitigation Incorporated. As discussed above, the project area is relatively flat, and landslides are not anticipated. Loose, unsaturated sandy soils can settle during strong seismic shaking. Because the soils encountered at the project site are predominantly stiff to very stiff clays and medium dense to dense sands, the potential for differential seismic settlement is considered low (Cornerstone 2016). As described above, the project applicant would be required to implement mitigation measure MM GEO-1, which includes measures to reduce or avoid the potential for significant impacts related to landslides, lateral spreading, subsidence, liquefaction, or collapse. Therefore, this impact would be less than significant with mitigation incorporated. d) Less Than Significant Impact. The geotechnical investigation encountered up to 2 feet of undocumented fill underlain by alluvial deposits, consisting of medium stiff to very stiff clay with varying percentages of sand and silt and above stiff silty and dense sand and gravels (Cornerstone 2016). The fill consisted of clayey sand with gravel and well -graded sand. Therefore, the project would not be located on expansive soil. The impact would be less than significant. e) No Impact. The project would connect to the City's sewage system and does not propose the use or construction of septic tanks or alternative wastewater disposal systems. Therefore, there would be no impact. Mitigation Measures MIA GEO-1 The project applicant shall implement all measures and recommendations set forth in the geotechnical study prepared by Cornerstone Earth Group in May 2016. These include but are not limited to: City of San Leandro November 2018 • Approximately 2 feet of undocumented clayey to well -graded sand fill was encountered below the surface. This loose fill shall be overexcavated and re -compacted within the proposed building footprint. Any undocumented fills encountered during the demolition of the northern building basement level shall also be re -compacted prior to the placement of new fill. • A portion of the proposed building would straddle deeper fill that would be required in order to fill the existing basement. Deeper fill transitions shall be overexcavated at an inclination of 3:1 or flatter and rebuilt with engineered fill to reduce the potential for differential movement beneath at -grade structures. • The corrosion potential for buried metallic structures, such as metal pipes, is considered moderate. Metal pipes installed as part of the project shall have special protection incorporated. Timing/Implementation: During grading and construction Enforcement/Monitoring: City of San Leandro Community Development Department; and Engineering and Transportation Department 1388 Bancroft Avenue Project Initial Study/Mitigated Negative Declaration 3.0-33