304 SE EVERETT MALL WAY PANERA BREAD Geotech Report 2025-07-25

KA No. 092-12004 August 24,2012 Page No.4 those encountered during the construction phase of the project. The evaluation of such factors is beyond the scope of this report. GEOLOGIC HAZARDS Erosion Concern/Hazard The Natural Resources Conservation Services(NRCS)maps for Snohomish County indicate that the site is underlain by Alderwood-Urban Land Complex(2 to 8 percent slopes). This soil type in relatively flat to gently sloping terrain has a moderate potential for erosion in areas that have been disturbed. It has been our experience that soil erosion potential can be minimized through landscaping and surface water runoff control. Typically erosion of exposed soils will be most noticeable during periods of rainfall and may be controlled by the use of normal temporary erosion control measures, i.e., silt fences, hay bales, mulching, control ditches or diversion trenching, and contour furrowing. Erosion control measures should be in place before the onset of wet weather. Seismic Hazard The soil borings indicate that the site is underlain by medium dense sand and gravel. In our opinion,the overall soil profile corresponds to a soil profile Site Class D as defined by Table 1613.5.2 of the 2009 International Building Code. Site Class D applies to a stiff soil profile. We referred to the U.S. Geological Survey(USGS)Earthquake Hazards Program Website and 2009 IBC to obtain values for SS, Si, FA, and Fv. The USGS website includes the most updated published data on seismic conditions. The site specific seismic design parameters are as follows: Seismic Item Value IBC Reference Site Class D Table 1613.5.2 Site Coefficient Fa 1.000 Table 1613.5.3 (1) Ss 1.427 Figure 1613.5 (3) SMs 1.427 Table 1613.5.3 SDS 0.951 Table 1613.5.4 Site Coefficient F„ 1.500 Table 1613.5.3 (2) Si 0.550 Figure 1613.5 (4) SM1 0.825 Section 1613.5.3 SD1 0.550 Section 1613.5.4 Krazan&Associates,Inc. Eleven Offices Serving The Western United States