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Sul surface Exploration, Geologic Hazard, and <br />St. Mary Magdalen Sport Court Prelintinary Geoiechnical Engineering Report <br />Everett, Washington _ Project and Site Conditions <br />sometimes be present due to the random nature of deposition and the alteration of topography <br />by past grading and/or filling. The nature and extent of any variations between the field <br />explorations may not become fully evident until construction. If variations are observed at that <br />time, it may be necessary to re-evaluate specific recommendations in this report and make <br />appropriate changej. <br />3.1 Exploration Pits <br />The exploration pits were excavated using a rubber -tired backhoe. The pits permitted direct, <br />visual observation of subsurface conditions. Materials encountered in the exploration pits were <br />studied and classified in the field by a geotechnical engineer from our firm. All exploration <br />pits were backfilled immediately after examination and logging. Selected samples were then <br />transported to our laboratory for further visual classification and testing, as necessary. <br />4.0 SUBSURFACE CONDITIONS <br />Subsurface conditions at the project site were inferred from the three field explorations <br />accomplished for this study, visual reconnaissance of the site, and review of selected geologic <br />literature. As shown on the field logs, the explorations generally encountered limited amounts <br />of fill soils over weathered and unweathered lodgement till. <br />4.1 Stratigraphy <br />We encountered fill soils within exploration pits EP-2 and EP-3. These fill soils generally <br />consisted of loose to medium dense, light brown, moist, silty sand with gravel aad some <br />cobbles. Fill soils were observed up to a depth of 1 to 2 feet below existing grade. These fill <br />soils were likely placed during the development of the surrounding infrastructure to create the <br />slope immediately north of the portable buildings and are not suitable for the support of <br />foun9ations or slabs. <br />Lodgement Till <br />Exploration pits ER--1, EP-2, and EP-3 encountered medium dense to dense„ mo`.�t, silty sand <br />with gravel interpreted as lodgement till. The lodgement till was observed below the top soil <br />and/or fill soils and extended to a depth beyond 7 feet. Lodgement till was deposited at the <br />base of the most recent continental glacier (Vashen Stade) some 12,000 to 15,000 years before <br />present and was subsequently compacted by the weight of.the overlying glacial ice. Due to the <br />April 24, 2006 ASSOCIATED EARTH SCIENCES, INC. <br />RAPrm-ki06026(1V- ProjMt12006026aIKENP Page 3 <br />