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Less than Significant Potentially With Less Than Significant Mitigation Significant No 6. GEOLOGY AND SOILS. Would the project: Impact Incorporated Impact Impact (a) Expose people or structures to potential substantial adverse effects, including the risk of loss,injury,or death involving: i) Rupture of a known earthquake fault,as delineated on the most recent Alquist-Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other substantial evidence of a ❑ ❑ ® ❑ known fault? Refer to Division of Mines and Geology Special Publication 42. ii) Strong seismic ground shaking? iii) Seismic-related ground failure,including liquefaction? iv) Landslides? (b) Result in substantial soil erosion or the loss of topsoil? (c) Be located on a geologic unit or soil that is unstable,or that would become unstable as a result of the project,and potentially result in on-or off-site ❑ ❑ ® ❑ landslide,lateral spreading,subsidence,liquefaction or collapse? (d) Be located on expansive soil,as defined in Table 18-1-B of the Uniform ❑ ❑ �� ❑ Building Code(1994),creating substantial risks to life or property? (e) Have soils incapable of adequately supporting the use of septic tanks or alternative waste water disposal systems where sewers are not available for ❑ ❑ ❑ El the disposal of waste water? Impact Analysis: a.i) The project site is not located within an Alquist-Priolo Fault Rupture Hazard Zone',as designated through the Aiquist-Priolo Earthquake Fault Zoning Act(Bryant and Hart,2007).No active faults are known to pass through the immediate project areal.The nearest active faults to the project site are the San Andreas Fault,located approximately 6 miles west of the site,and the Hayward Fault,located approximately 13 miles east of the site.Although fault rupture is not necessarily bound by the limits of a fault rupture hazard zone,ground displacement is most commonly seen along traces of active faults during major earthquakes that result in observable offsets. Because the site is not located on or relatively close to an active or potentially active fault,the potential for surface rupture is low and the impact would be less than significant. a.ii-iii) The project site is located in the San Francisco Bay Area,a seismically active region of California with numerous active faults. Seismic activity in the region is dominated by the San Andreas Fault system, which includes the San Andreas,Hayward,and Calaveras faults.According to the U.S. Geological Survey(USGS)Working Group on Earthquake Probabilities(2008),the probability of one or more earthquakes of Richter magnitude 6.7 or higher occurring in the San Francisco Bay Area for the 30-year period from 2008 to 2038 is 62 percent. The Hayward and San Andreas are the most likely of the Bay Area faults to experience a major earthquake.The probability of an earthquake magnitude 6.7 or higher occurring anywhere along the Hayward Fault during this period was determined to be 27 percent; and 21 percent for the San Andreas Fault. In the event of a large earthquake on one of these faults,the project site is expected to experience strong to very strong ground shaking(ABAG,2009a). Alquist-Priolo Zones designate areas most likely to experience fault rupture,although surface fault rupture is not necessarily restricted to those specifically zoned areas. 2 Active faults are defined as those faults which show evidence of movement within the last 11,000 years(Holocene);potentially active faults are defined as those that have shown evidence of surface displacement over the last 1.6 million years(Quaternary). Port of Redwood City Multi-Agency Maritime Facility 25 February 2010 Initial Study