Laserfiche WebLink
Liquefaction and Differential Settlement <br /> Liquefaction is the result of seismic activity and is characterized as the transformation of loose water <br /> saturated soils from a solid state to a liquid state during ground shaking. Soils most susceptible to <br /> liquefaction are loose to moderately dense, saturated,non-cohesive soils with poor drainage. <br /> Differential settlement is the unequal settlement of material that causes a gradual,uneven downward <br /> movement of a structure's foundation. According to the California Department of Conservation,the <br /> project site is located in an area with historical occurrences of liquefaction, or local geological, <br /> geotechnical, and groundwater conditions that indicate the potential for permanent ground <br /> displacements.13 <br /> Lateral Spreading <br /> Lateral spreading is a type of ground failure related to liquefaction. It consists of the horizontal <br /> displacement of flat-lying alluvial material toward an open area, such as the steep bank of a stream <br /> channel. There are no creek banks or other open areas in the project vicinity; therefore,the risk of <br /> lateral spreading at the site is low. <br /> 4.6.2 Environmental Checklist and Discussion of Imnacts <br /> GEOLOGY AND SOILS <br /> Potentially Less Than SigniYicani Less Than Beneficial Information <br /> Significant With Mitigation Significant No Impact �p�� Source(s) <br /> Impact Inco orated Im act <br /> Would the project: <br /> 1) Expose people or structures to <br /> potential substantial adverse effects, <br /> including the risk of loss,injury, or <br /> death involving: <br /> a) Rupture of a known earthquake � � � � � 1,2,3,9 <br /> fault, as described on the most <br /> recent Alquist-Priolo Earthquake <br /> Fault Zoning Map issued by the <br /> State Geologist for the area or <br /> based on other substantial <br /> evidence of a known fault? <br /> (Refer to Division of Mines and <br /> Geology Special Publication 42.) <br /> b) Strong seismic ground shaking? � � � � � 1,2,3 <br /> c) Seismic-related ground failure, � � � � � 1,2,3 <br /> including liquefaction? <br /> d) Landslides? � � � � � 1,2,3 <br /> 2) Result in substantial soil erosion or � � � � � 1,2,3 <br /> the loss of to soil? <br /> 13California Department of Conservation. Seismic Hazards Zones,Palo fllto Quadrangle. October 18,2006. <br /> <http://�mw.consrv.ca.gov/slun�/download/pdf/ozn paloa.pdf> Accessed July 26,2012. <br /> Kensington Assisted Living Facility Project 37 Initial Study <br /> Redwood City Apri12013 <br />