902 PINE ST NORTH SOUND BEHAVIORAL HEALTH TREATMENT CENTER 2025-11-04

GeoTest Services,Inc. November 16,2018 North Puget Sound Behavioral Health—Treatment Center Addition Job No. 18-0770 Site Class Definition I For structures designed using the seismic design provisions of the 2015 International Building Code, the underlying till soils interpreted to underlie the site within the upper 100 feet classifies as Site Class D according to 2010 ASCE -7 Standard — Table 20.3-1, Site Class Definitions. The corresponding values for calculating a design response spectrum for the assumed soil profile type is considered appropriate for the site. I Please use the following values for seismic structural design purposes: Conterminous 48 States—2015 International Building Code Zip Code 98201 Central Latitude = 48.005478, Central Longitude = -122.192360 I Short Period (0.2 sec) Spectral Acceleration Maximum Considered Earthquake (MCE) Value of Ss= 1.248 (g) Site Response Coefficient, Fa= 1.001 (Site Class D) Adjusted spectral response acceleration for Site Class D, SMs = Ssx Fa = 1.249 (g) Design spectral response acceleration for Site Class D, SDS = 2/3 x SMs= 0.833 (g) I One Second Period (1 sec) Spectral Acceleration Maximum Considered Earthquake (MCE)Value of Si = 0.476 (g) Site Response Coefficient, Fv= 1.524 (Site Class D) Adjusted spectral response acceleration for Site Class D, SMi = Si x Fv = 0.725 (g) Design spectral response acceleration for Site Class D, So, = 2/3 x SM1 = 0.484(g) ' Foundation Support and Settlement We recommend that all footing locations be placed on dense to very dense native soil, ' which was found shallowly at about 1-foot BGS across most exploration locations at the project site. We recommend that all topsoil, organic soil, existing fill soils, or deleterious material be removed from below footing areas. We recommend recompaction and proof rolling along with verification by a GTS representative of all building foot print area soils prior to placement of foundation elements. GTS should be present during site stripping activities to confirm the removal of the topsoil or any potential unsuitable soil from construction areas. Foundation support for the proposed improvements may be provided by continuous or isolated spread footings founded on proof-rolled or recompacted, undisturbed, firm and unyielding glacial till soils or on properly compacted structural fill placed directly over firm and unyielding glacial till. In areas requiring overexcavation to competent soils, the limits of the overexcavation should extend laterally beyond the edge of each side of the footing a distance equal to the depth of the fill. If structural fill is used to backfill the overexcavation, the limits of the overexcavation need only extend a nominal distance beyond the width of the footing. All continuous and isolated spread footings should be founded a minimum of 18 inches I below the lowest adjacent final grade for freeze/thaw protection. Page 8 of 17