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Geotechnical Report <br /> Proposed Student Housing: 931 Broadway Street, Everett, Washington <br /> December 8, 2015 <br /> 3.0 SUBSURFACE EXPLORATIONS <br /> 3.1 SITE GEOLOGY <br /> General geologic information for the project area was obtained by reviewing the <br /> Geologic Map of the Marysville Quadrangle, Snohomish County, Washington (Minard <br /> 1985). Based on our review, the project site is underlain by Vashon Till — Geologic Map <br /> Unit Qvt. Vashon Till consists of an unsorted deposit (diamict) of clay, silt, sand and <br /> gravel that has been glacially transported and deposited. This soil has been directly <br /> deposited by a glacier and overridden by several thousand feet of glacial ice and is <br /> typically dense to very dense. <br /> 3.2 SUBSURFACE EXPLORATION <br /> Three borings (PG-1 through PG-3) were drilled at the subject site on November 23, <br /> 2015. The borings were drilled using a track-mounted drill rig operated by Boretec, Inc. <br /> subcontracted to PanGEO and were logged by a geologist with our firm. The borings <br /> were drilled to a maximum depth of 16 feet below existing grade. The approximate <br /> boring locations were located in the field by measuring from property corners and site <br /> features and are shown on Figure 2, Site and Exploration Plan. <br /> Standard Penetration Tests (SPT) were performed at 21/4- to 5-foot depth intervals using a <br /> standard, 2-inch diameter split-spoon sampler. The sampler was advanced with a 140- <br /> pound drop hammer falling a distance of 30 inches for each strike, in general accordance <br /> with ASTM D-1586, Standard Test Method for Penetration Test and Split Barrel <br /> Sampling of Soils. <br /> The soils were logged in general accordance with ASTM D-2487 Standard Practice for <br /> Classification of Soils for Engineering Purposes and the system summarized on Figure <br /> A-1, Terms and Symbols for Boring and Test Pit Logs. Summary boring logs are <br /> included as Figures A-2 through A-4 in Appendix A. <br /> 3.3 SOIL CONDITIONS <br /> For a detailed description of the subsurface conditions encountered at each exploration <br /> location, please refer to our boring logs provided in Appendix A. The stratigraphic <br /> contacts indicated on the boring logs represent the approximate depth to boundaries <br /> between soil units. Actual transitions between soil units may be more gradual or occur at <br /> 15-275 931 Broadway,Everett P % PanGEO,Inc. <br />