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COBALT <br />GEOSCIENCES <br />October 19, 2021 <br />Rick Hardt <br />rvhardt(d)gmail.com <br />RE: Geotechnical Evaluation <br />Proposed Residential Development <br />953o Holly Drive <br />Everett, Washington <br />Cobalt Geosciences, LLC <br />P.O. Box 82243 <br />Kenmore, Washington 98028 <br />In accordance with your authorization, Cobalt Geosciences, LLC has prepared this letter to <br />discuss the results of our geotechnical evaluation at the referenced site. <br />The purpose of our evaluation was to provide recommendations for foundation design, grading, <br />and earthwork. <br />Sife Descripfion <br />The site is located at 953o Holly Drive in Everett, Washington. The site consists of one irregularly <br />shaped parcel (No. 003787002oo600) with a total area of 1.21 acres. <br />The southeast portion of the site is developed with a residence and driveway. The remainder of <br />the properties are vegetated with grasses, bushes, trees, and blackberry vines. <br />The site is mostly level to slightly sloping downward to the south. The site is locally undulating <br />with total relief of about 6 feet. <br />The site is bordered to the north and east by residences, to the west by a school, and to the south <br />by Holly Drive. <br />The proposed development includes 7 residential lots, access roadways, stormwater management <br />systems, and utilities. Stormwater will include infiltration or other systems depending on <br />feasibility. Site grading may include cuts and fills of 4 feet or less and foundation loads are <br />expected to be light. We should be provided with the final plans to verify that our <br />recommendations remain valid and do not require updating. <br />Area Geology <br />The Geologicp of the Everett Quadrangle, indicates that the site is underlain by Vashon <br />Glacial Till. <br />Vashon Glacial Till includes mixtures of silt, sand, clay, and gravel. These materials are usually <br />impermeable and are typically dense to very dense below a weathered zone. <br />Soil & Groundwafer Condifions <br />As part of our evaluation, we excavated two test pits and two hand borings within the property, <br />where accessible. There was limited space for additional test pits. <br />The explorations encountered approximately 6 to 24 inches of grass and topsoil underlain by <br />approximately 3 to 3.5 feet of loose to medium dense, silty -fine to fine grained sand trace to with <br />gravel (Weathered Glacial Till). These materials were underlain by dense to very dense, silty -fine <br />www.cobaltgeo.com (2o6) 331-1097 <br />