2930 MAPLE ST KAISER PERMANENTE Geotech Report 2025-03-07

Geotechnical Engineering Report-Revised lrerracon Kaiser Everett Medical Center Everett,Washington -- s--- y� December 18, 2019 Terracon Project No. 81195071 GeoReport Description Value FPCA—Peak Ground Acceleration Site Coefficient 1.000 The IBC requires a site profile extending to a depth of 100 feet for seismic site classification. Borings were extended to a maximum depth of 40 feet. The site properties below the boring depth to 100 feet were estimated based on our experience and knowledge of geologic conditions of the general area. 2. These values were obtained using online seismic design maps and tools provided by OSHPD (https://seismicmaps.org ). ASCE 7 allows site coefficients Fa and Fy to be determined assuming that liquefaction does not occur for structures with fundamental periods of vibration less than 0.5 second. Based on the results of the exploration program,Site Class C may be used to determine the values of Fa and F,,.The fundamental period of vibration for the structure should be verified by the structural engineer. Surface-Fault Rupture The hazard of damage from onsite fault rupture appears to be low based on review of the USGS Earthquake Hazards Program Quaternary Faults and Folds Database available online (https://usgs.maps.arcgis.com/apps/webappviewer/index.html?id=5a6O38b3a1684561 a9bOaadf 88412fcf) accessed on June 10, 2019. The closest mapped fault is the Southern Whidbey Island fault zone, which lies approximately 6.8 miles to the southwest of the site. LIQUEFACTION Liquefaction is the phenomenon where saturated soils develop high porewater pressures during seismic shaking and lose their strength characteristics. This phenomenon generally occurs in areas of high seismicity, where groundwater is shallow and loose granular soils or relatively non- plastic fine-grained soils are present. Based on the site geology and subsurface groundwater conditions, we anticipate that the risk of liquefaction of the site soils is low. FLOOR SLABS Design parameters for floor slabs assume the requirements for Earthwork have been followed. Specific attention should be given to positive drainage away from the structure and positive drainage of the aggregate base beneath the floor slab. Floor Slab Design Parameters Item Description Minimum 6 inches of capillary break material consisting of free-draining, Floor Slab Support granular material with less than 3% retained on the#200 sieve) Responsive ■ Resourceful ■ Reliable