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October 16,2020 <br /> Project No. T-8221 <br /> It should be noted that the recommendations outlined in this report regarding drainage are associated with soil <br /> strength,erosion,and stability. Design and performance issues with respect to moisture as it relates to the structure <br /> environment(i.e.,humidity,mildew,mold)are beyond Terra Associates' purview. A building envelope specialist <br /> or contractor should be consulted to address these issues, as needed. <br /> 3.0 SITE CONDITIONS <br /> 3.1 Surface <br /> Currently, the site is an undeveloped relatively flat parcel of land with sparse ground cover consisting of grass, <br /> moss,and scattered Scotch Broom and young tree saplings. There is a stockpile of large basalt rocks present in the <br /> east-central portion of the site. The site is bounded on three sides by water associated with the Snohomish River <br /> channel as it discharges into Possession Sound. The perimeter of the site adjacent the shoreline is heavily vegetated <br /> with blackberry brambles. The east side of the site is bounded by West Marine View Drive. The approximate <br /> location of the site is shown on Figure 1. <br /> Based on review of a previous July 1995 report,prepared by Landau Associates,Inc.historically the site was created <br /> by incremental infilling of the near shore tidelands and had been used by a sawmill producing timber products for <br /> 50 years. Sawmill operations ceased in 1979 and the site was then used as a log handling yard up until 1994. Site <br /> exploration completed by Landau in 1994 showed the site was covered by a significant amount of wood waste <br /> material with wood waste and organic soils observed to depths of two to eight feet below site grades that existed at <br /> that time. Recent work completed at the site by Shannon and Wilson for the Port of Everett indicates that this wood <br /> waste material was excavated and removed from the site in 1995 and site grades restored to match surrounding site <br /> grades with dredge sands from the Snohomish River channel. Site reconnaissance completed by Terra personnel <br /> for this report found no evidence of wood waste material near-surface. <br /> 3.2 Soils <br /> Previous and current site exploration data indicates soils in the upper approximately 10 to 12 feet consist of fill <br /> composed mostly of sand and silty sand mixed with occasional construction rubble including concrete, asphalt, <br /> geotextile fabric, and metal along with trace to little wood debris. Recent CPT exploration indicate the fill is <br /> moderately well compact below the upper one to two feet. Below the fills, alluvium composed initially of a thin <br /> one-to two-foot layer of very loose silt is indicated followed by sand and silty sand alluvium to depths of 50 to 65 <br /> feet below current site grades. The relative density of the sand alluvium was medium dense to a depth of about 25 <br /> feet with dense conditions indicated to the bottom of the layer. Below this sand unit, soft clayey silt/silty clay <br /> sediments are indicated to the CPT termination depths of 80 feet. <br /> Review of geologic information from the Washington Geologic Information Portal located at the web site <br /> https://geologyportal.dnr.wa.gov/maps the soils at the site as Qyal,Younger alluvium and estuarine deposits. The <br /> deposits are described as being largely sand, silt, and clay with considerable amount of organic matter. With the <br /> exception of the organic matter,this map unit is consistent with the native soils found beneath the fills. <br /> Page No. 2 <br />