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City of Pleasanton—Hidden Canyon Residences and Preserve Draft EIR Geology, Soils, and Seismicity FirstCarbon Solutions 3.6-19 https://adecinnovations.sharepoint.com/sites/PublicationsSite/Shared Documents/Publications/Client (PN-JN)/2148/21480016/EIR/3 - Draft EIR/21480016 Sec03-06 Geology.docx The SVP’s Standard Guidelines identify that project sites with rock units having high, undetermined, and low potential should perform a paleontological resource impact assessment before ground- disturbing activities begin, including performing a literature review, field survey, and consulting with a certified repository institution with localities in the project region. Project sites that contain rock units having high or undetermined potential should prepare a paleontological resource impact mitigation plan including monitoring ground-disturbing activities, and appropriate methods for salvaging, sampling, identifying, preparing, cataloging, curating, and storing significant paleontological resources uncovered during ground-disturbing activities. Most practicing professional paleontologists in the nation adhere to the SVP’s Standard Guidelines. State Alquist-Priolo Earthquake Fault Zoning Act The Alquist-Priolo Earthquake Fault Zoning Act (Public Resources Code [PRC] Sections 2621 to 2630) was passed in 1972 to provide a statewide mechanism for reducing the hazard of surface fault rupture to structures used for human occupancy. The main purpose of the Act is to prevent the siting of buildings used for human occupancy across the traces of active faults. It should be noted that the Act addresses the potential hazard of surface fault rupture and is not directed toward other earthquake hazards, such as seismically induced ground shaking or landslides. The law requires the State Geologist to identify regulatory zones (known as Earthquake Fault Zones or Alquist-Priolo Earthquake Fault Zones) around the surface traces of active faults, and to depict these zones on topographic base maps, typically at a scale of 1 inch to 2,000 feet. Earthquake Fault Zones vary in width, although they are often 0.75-mile wide. Once published, the maps are distributed to the affected cities, counties, and State agencies for their use in planning and controlling new or renewed construction. With the exception of single-family wood frame and steel frame dwellings that are not part of a larger development (i.e., four units or more), local agencies are required to regulate development within the mapped zones. In general, construction within 50 feet of an active fault zone is prohibited. Seismic Hazards Mapping Act The Seismic Hazards Mapping Act (PRC §§ 2690–2699.6), which was passed in 1990, addresses earthquake hazards other than surface fault rupture. These hazards include strong ground shaking, earthquake-induced landslides, liquefaction, or other ground failures. Much like the Alquist-Priolo Earthquake Fault Zoning Act discussed above, these seismic hazard zones are mapped by the State Geologist to assist local government in the land use planning process. The Seismic Hazards Mapping Act states, “it is necessary to identify and map seismic hazard zones in order for cities and counties to adequately prepare the safety element of their general plans and to encourage land use management policies and regulations to reduce and mitigate those hazards to protect public health and safety.” The Seismic Hazards Mapping Act also states, “cities and counties shall require, prior to the approval of a project located in a seismic hazard zone, a geotechnical report defining and delineating any seismic hazard.”