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Environmental Checklist Geology and Soils <br /> Initial Study – Mitigated Negative Declaration 35 <br />Landslides and Erosion <br />Landslides are relatively common in the East Bay Hills, particularly during high intensive bouts of <br />rainfall. A majority of landslides occur naturally, however their impacts can be induced by excessive <br />grading, improper construction, and poor drainage. The City enforces grading and erosion control <br />ordinances to reduce erosion hazards such as landslides, siltation of streams, undermining of <br />foundations, and loss of structures. <br />Lateral Spreading <br />Lateral spreading is horizontal/lateral ground movement of relatively flat-lying soil deposits towards <br />a free face such as an excavation, channel, or open body of water. Typically, lateral spreading is <br />associated with liquefaction of one or more subsurface layers near the bottom of the exposed slope. <br />As failure tends to propagate as block failures, it is difficult to analyze and estimate where the first <br />tension crack will form (Cornerstone 2016). <br />Ground Shaking <br />Ground shaking occurs as a result of energy released during faulting, which could potentially result <br />in the damage or collapse of buildings and other structures, depending on the magnitude of the <br />earthquake, the location of the epicenter, and the character and duration of the ground motion. <br />Regulatory Setting <br />California Building Code (CBC) <br />The CBC is Part 2 of Title 24 of the California Code of Regulations and is updated every three years. <br />With the exception of certain enforcement provisions, the City of San Leandro adopted the CBC by <br />reference pursuant to Title 7, Chapter 7-5, Article 1, Section 7-5-100 of the San Leandro Municipal <br />Code (SLMC). Through the CBC, the state provides a minimum standard for building design and <br />construction. Of particular relevance, Chapter 16 of the CBC contains specific requirements for <br />structural (building) design, including seismic loads. Chapter 18 of the CBC includes requirements for <br />soil testing, excavation and grading, and foundation design (San Leandro 2016f). Section 1803A <br />requires geotechnical investigations for all new construction except for one-story, wood-frame and <br />light steel frame buildings with 4,000 square feet or less in floor area. <br />San Leandro Municipal Code <br />Chapter 7-5, Building Code, of the SLMC adopts the 2016 California Building Code as the City’s <br />Building Code. Chapter 7-12 of the SLMC (Grading, Excavations, and Fills) includes a grading <br />ordinance that seeks to mitigate hazards associated with erosion and land stability. The ordinance <br />establishes requirements for grading permits, including submittal and construction requirements. <br />An erosion and sedimentation control plan must be submitted with a grading permit application, <br />along with a drainage plan and pollution control plan (San Leandro 2016f). <br />Impact Analysis <br />a.1. Expose people or structures to potential substantial adverse effects, including the risk of loss, <br />injury, or death involving rupture of a known earthquake fault, as delineated on the most <br />recent Alquist-Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area or <br />based on other substantial evidence of a known fault? <br />332