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Proposal for Geotechnical Engineering Services <br />Proposed Apartments: 1020 North Broadway, Everett, Washington <br />September 27, 2017 <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 were drilled on the property on August 10, 2017. The borings were drilled <br />using a track -mounted drill rig operated by Boretec, Inc. under subcontract to PanGEO <br />and were logged by a geologist with our firm. The borings were drilled to a maximum <br />depth of 15 %2 feet below existing grade. The approximate boring locations were located <br />in the field by measuring from property corners and site features and are shown on Figure <br />2, Site and Exploration Plan. <br />Standard Penetration Tests (SPT) were performed at 2%2- 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. <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 />different elevations. The descriptions of groundwater conditions and depths are likewise <br />17-233 1020 North Broadway Page 3 PanGEO, Inc. <br />