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Subsurface Exploration,Geologic Hazards,and <br /> Former Brien Ford Preliminary Geotechnical Engineering Report <br /> Everett, Washington Project and Site Conditions <br /> 4.1 Stratigraphy <br /> Asphalt/Concrete <br /> A surficial layer of existing asphalt was encountered at the location of EB-1. The asphalt was <br /> approximately 2 inches in thickness. In the push-probe explorations the asphalt ranged in <br /> thickness from 3 to 4 inches. Concrete slabs were also encountered in our push-probe <br /> explorations and ranged in thickness from 3 to 8 inches. <br /> Fill <br /> Fill soils (those not naturally placed) were encountered in location EB-1 directly below the <br /> surficial asphalt.The fill consisted of loose to dense, slightly moist, brownish gray with oxidation <br /> staining, fine to medium sand with variable amounts of silt and gravel, and trace amounts of <br /> wood debris. The fill material appeared to consist primarily of materials derived onsite and <br /> moved or disturbed during earlier site work. Existing fill was also encountered in 27 of the <br /> push-probe explorations below the asphalt or concrete surface and extended to approximate <br /> depths ranging from 2 to 11 feet below the surface. The fill in these explorations generally <br /> consisted of loose to dense, silty to very silty sand or sand with trace silt and varying amounts <br /> of gravel. Existing fill soils are not suitable for support of foundation underpinning elements. <br /> Uncontaminated existing fill may be reused as structural fill if allowed by project specifications <br /> and all deleterious materials are removed. <br /> Ice-Contact Deposits <br /> Ice-contact deposits were encountered in 28 of 29 direct-push probe explorations completed <br /> for the previous studies. These deposits were generally encountered underlying asphalt or <br /> concrete surfacing or underlying existing fill soils. Where encountered, these deposits <br /> extended to the depths explored of 15 feet or less or were underlain by Vashon advance <br /> outwash sediments. The ice-contact sediments generally consisted of moist to wet, fine to <br /> coarse sand, silty or very silty fine to coarse sand, sandy silt, silt with trace sand, and clay all <br /> with variable gravel content. The ice-contact deposits were not consolidated by an overriding <br /> glacier but were deposited in topographic depressions by the meltwater of the receding glacier. <br /> The ice-contact deposits were over optimum in moisture content at the time of the exploration <br /> and would require drying during favorable weather prior to compaction and potential reuse in <br /> structural fill applications. <br /> Vashon Advance Outwash <br /> Advance outwash sediments were encountered in exploration EB-1 directly below the fill soils <br /> and were also encountered underlying ice-contact sediments in several of the push-probe <br /> explorations. Advance outwash sediments were deposited in rivers and streams flowing ahead <br /> of an advancing glacier, and were subsequently compacted by the weight of the overlying <br /> May 16,2017 ASSOCIATED EARTH SCIENCES,INC. <br /> AWR/Id-160594V003-2-Projects\201605941KV1WP Page 4 <br />