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August 13,2008 <br /> Project No. T-6241 <br /> 4.3 Seismic Hazard <br /> Title 19,Chapter 4.020 of the EMC defines seismic hazard areas as "those areas of the city subject to severe risk <br /> of earthquake damage as a result of seismically induced ground shaking, settlement, or soil liquefaction". <br /> Potential landslide hazard areas in the City of Everett are classified based on the risk as determined by the <br /> publication Dames and Moore Methodology for the Inventory, Classification and Designation of Geologically <br /> Hazardous Areas, City of Everett, Washington:July 1, 1991. <br /> Section 19.37.080(A)(2)of the EMC defines seismic hazard areas as: <br /> a. Those areas mapped as seismic/liquefaction hazards per the Dames and Moore Methodology for the <br /> Inventory, Classification and Designation of Geologically Hazardous Areas, City of Everett,Washington: <br /> July 1, 1991. <br /> b. Those areas mapped as high and moderate to high liquefaction susceptibility on the Liquefaction <br /> ' Susceptibility Map of Snohomish County, Washington, Washington State Department of Natural <br /> Resources,Palmer,Stephen,et al.,September,2004. <br /> Considering the site is underlain by glacially consolidated and overridden sediments, it is our opinion that the <br /> potential for earthquake damage at the site resulting from seismically induced differential settlement, and ground <br /> shaking is negligible. <br /> Liquefaction is a phenomenon where there is a reduction or complete loss of soil strength due to an increase in <br /> ' water pressure induced by vibrations. Liquefaction mainly affects geologically recent deposits of fine-grained <br /> sands that are below the groundwater table. Based on the soil and groundwater conditions we observed in our <br /> site explorations, it is our opinion that there is no risk for liquefaction to occur at this site during a severe seismic <br /> event. <br /> Seismic Site Class <br /> Based on soil conditions observed in our site explorations and our review of local geologic literature, per the <br /> 2006 International Building Code(WC),site class"C"should be used in structural design. <br /> 5.0 DISCUSSION AND RECOMMENDATIONS <br /> 5.1 General <br /> Based on our study, there are no geotechnical conditions that would preclude the planned development. <br /> Commercial structures can be supported on conventional spread footings bearing on competent native soils <br /> ' underlying the organic surficial soils, or on structural fill placed on a subgrade of competent native soils. Floor <br /> slabs and pavements can be similarly supported. <br /> I <br /> ' Page No. 6 <br />