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Proposal for Geotechnical Engineering Services <br />Proposed Bank: 1515 132"d Street Southeast, Everett, Washington <br />March 15, 2019 <br />3.0 SUBSURFACE EXPLORATIONS <br />3.1 SITE GEOLOGY <br />General geologic information for the project area was obtained by reviewing the Geologic <br />Map of the Everett 7.5-Minute Quadrangle, Snohomish County, Washington (Minard <br />1985). Based on our review, the geologic units in the vicinity of the site consist of Vashon <br />Till — Geologic Map Unit Qvt. Vashon Till consists of an unsorted deposit (diamict) of <br />clay, silt, sand and gravel that has been glacially transported and deposited. This soil has <br />been directly deposited by a glacier and overridden by several thousand feet of glacial ice <br />and is typically dense to very dense. <br />3.2 SUBSURFACE EXPLORATION <br />We drilled three borings at the site on March 6, 2019. The borings were drilled using a <br />trailer -mounted drill rig owned and operated by Geologic Drill, Inc. under subcontract to <br />PanGEO and were logged by a geologist with our firm. The borings were drilled to a <br />maximum depth of 20V2 feet below existing grade. The approximate boring locations were <br />located in the field by measuring from property corners and site features and are shown on <br />Figure 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 Sampling <br />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 A- <br />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 contacts <br />indicated on the boring logs represent the approximate depth to boundaries between soil <br />units. Actual transitions between soil units may be more gradual or occur at different <br />elevations. The descriptions of groundwater conditions and depths are likewise <br />19-049 1515 132nd St SE Page 3 PanGEO, Inc. <br />