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SAN LEANDRO SHORELINE DEVELOPMENT DRAFT EIR <br />CITY OF SAN LEANDRO <br />GEOLOGY, SOILS, AND SEISMICITY <br />4.5 GEOLOGY, SOILS, AND SEISMICITY <br />This chapter provides an overview of the regulatory framework and existing geologic conditions on the <br />Project site and evaluates potential environmental impacts of the Project related to geology, soils, and <br />seismicity. <br />4.5.1 ENVIRONMENTAL SETTING <br />4.5.1.1 REGULATORY FRAMEWORK <br />This section summarizes key State and local regulations pertaining to geology, soils, and seismicity that are <br />applicable to the Project. There are no federal regulations relating to geology, soils, and seismicity <br />applicable to the Project. <br />State Regulations <br />Alquist-Priolo Earthquake Fault Zoning Act <br />The Alquist-Priolo Earthquake Fault Zoning Act was passed in 1972 to mitigate the hazard of surface <br />faulting to structures used for human occupancy.` The main purpose of the Act is to prevent the <br />construction of buildings used for human occupancy on top of active faults. The Act only addresses the <br />hazard of surface fault rupture and is not directed toward other earthquake hazards, such as ground <br />shaking or landslides.' <br />The law requires the State Geologist to establish regulatory zones (known as Earthquake Fault Zones or <br />Alquist-Priolo Zones) around the surface traces of active faults, and to issue appropriate maps.' The maps <br />are then distributed to all affected cities, counties, and State agencies for their use in planning and <br />controlling new or renewed construction. Generally, construction within 50 feet of an active fault zone is <br />prohibited. <br />San Leandro is listed as a city affected by Alquist-Priolo Earthquake Fault Zones.' <br />Seismic Hazards Mapping Act <br />The Seismic Hazards Mapping Act, passed in 1990, addresses non -surface fault rupture earthquake <br />hazards, including liquefaction and seismically induced landslides.' Under this Act, seismic hazard zones <br />are mapped by the State Geologist to assist local governments in land use planning. Section 2691(c) of the <br />1 Called the Alquist-Priolo Special Studies Zones Act until renamed in 1993. <br />2 California Geological Survey, Alquist-Priolo Earthquake Fault Zones, http://www.consry.ca.gov/CGS/rghm/ap/Pages/ <br />Index.aspx, accessed on July 17, 2014. <br />3 Earthquake Fault Zones are regulatory zones around active faults. The zones vary in width, but average about X -mile -wide. <br />http://www.consrv.ca.gov/cgs/rghm/ap/Pages/main.aspx, accessed on July 17, 2014. <br />' California Geological Survey, Cities and Counties Affected by Alquist-Priolo Earthquake Fault Zones as of January 2010, <br />http://www.conservation.ca.gov/cgs/rghm/ap/Pages/affected.aspx, accessed on July 23, 2014. <br />5 California Geological Survey, Alquist-Priolo Earthquake Fault Zoning Act, http://www.consry.ca.gov/cgs/rghm/ap/Pages/ <br />main.aspx, accessed on July 17, 2014. <br />PLACEWORKS 4.5-1 <br />