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City of Pleasanton—Hidden Canyon Residences and Preserve Draft EIR Geology, Soils, and Seismicity FirstCarbon Solutions 3.6-25 https://adecinnovations.sharepoint.com/sites/PublicationsSite/Shared Documents/Publications/Client (PN-JN)/2148/21480016/EIR/3 - Draft EIR/21480016 Sec03-06 Geology.docx approximately 0.7 mile east and does not incorporate the project site. Since fault lines beneath the project site are considered inactive and the project site is not located within a Special Study Zone, impacts related to directly or indirectly causing loss, injury, or death involving fault rupture would be less than significant. ii) Strong Ground Shaking As previously mentioned, four major right lateral strike-slip faults part of the San Andreas Fault Zone are within 15 miles of the project site along with lesser-known faults. The Calaveras Fault, located approximately 0.7 mile east of the project site, is capable of generating an MMI VIII earthquake which is designated as very strong shaking that can damage buildings. In addition, the reoccurrence interval of the Southern Hayward segment of the Hayward Fault is approximately 150-205 years according to paleo seismic studies and the last maximum event occurred 157 years ago which produced a projected magnitude of 7.0 on the Richter Scale. As such, development of the proposed project may expose new residents to an area prone to strong seismic shaking which could result in the direct or indirect loss, injury, or death of those inhabiting the project site in the future. However, the proposed project would be required to incorporate building design standards based on Sound Engineer judgment and minimum seismic design provisions by the CBC. The intent of the CBC provisions is to enable structures to (i) resist minor earthquakes without damage, (ii) resist major earthquakes without structural damage but with some nonstructural damage, and (iii) resist major earthquakes without collapse but with some structural as well as nonstructural damage. In addition, the proposed project would be required to meet the goals, policies, and programs related to strong seismic shaking in the General Plan such as Policy 2 which requires the implementation of soil engineering and construction standards to minimize strong seismic shaking, Program 2.1 requiring geotechnical engineering studies for developments within areas capable of experiencing severe to violent strong seismic shaking, and Program 5.1 which mandates site-specific soil studies for new developments to address seismic shaking prior to the issuance of building permits. Further, Program 2.2 supplements minimum seismic design provisions from the CBC by requiring the implementation of CBC standards into all structures to address seismic hazards. Since the proposed project would adhere to seismic design provisions by the CBC and other requirements in the General Plan, impacts related to the direct or indirect risk of loss, injury, or death involving strong seismic shaking would be less than significant. iii) Ground Failure and Liquefaction Subsurface conditions within the main development area of the project site include residual and colluvium comprised of a thin layer of clay overlaying sedimentary bedrock with no groundwater present between three to 18 feet below the surface. As previously mentioned, soils susceptible to liquefaction are loose and saturated unconsolidated sands with a shallow water table. Based on the findings of the Updated Geotechnical and Geologic Report, the main development area and areas of higher elevation on the project site have a low liquefaction potential. While the project has been designed to avoid development within Liquefaction Zones, both the southeastern boundary of the project site and northeastern portion of the project site, which would redevelop two existing single- family homes, are located within a designated as a Liquefaction Zone of Required Investigation by