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Geotechnical Engineering Evaluation NGA File No. 1165620 Lyashenko Accessory Dwelling Unit Development April 10, 2020 Everett, Washington Page 2 SITE CONDITIONS Surface Conditions The site consists of a rectangular -shaped parcel covering approximately 0.81 acres. The property is currently occupied with an existing single-family residence within the central portion of the property. An asphalt driveway accessing South 2nd Avenue descends into the residence garage from the southwestern portion of the property. Topography within the site is generally relatively level to gently sloping from west to east. The ground surface is covered with mostly grass yard areas and young to mature trees around the perimeter of the site. The site is bordered to the north and south by existing residential properties, to the west by South 2nd Avenue, and to the east by undeveloped land. We did not observe surface water throughout the site during our visit on March 19, 2020. Subsurface Conditions Geology: The geologic units for this site are shown on Geologic map of the Everett 7.5 minute quadrangle, Snohomish County, Washington by Minard, J.P. (USGS, 1985). The site is mapped on the contact line of glacial till (Qvt) and transitional beds (Qtb) with advance outwash (Qva) in close proximity. Till is generally described as a compact, non -sorted mixture of clay, silt, sand, pebbles, cobbles, and boulders. Transitional Beds are described as deposits consisting of clay, silt, and very fine to fine sand. Advance outwash is described as clean, well stratified sand with gravel and cobbles. Our explorations typically encountered undocumented fill underlain by fine to medium sand with silt, silt lenses, and gravel which we interpreted as native advance outwash deposits. Explorations: The subsurface conditions within the site were explored on March 19, 2020 by excavating four test pits to approximate depths in the range of 5.0 to 10.0 feet below the existing ground surface using a mini-trackhoe. The approximate locations of our explorations are shown on the Site Plan in Figure 2. A geologist from NGA was present during the explorations, examined the soils and geologic conditions encountered, obtained samples of the different soil types, and maintained logs of the test pits. The soils were visually classified in general accordance with the Unified Soil Classification System, presented in Figure 3. The logs of our test pits are attached to this report and are presented as Figure 4. We present a brief summary of the subsurface conditions in the following paragraph. For a detailed description of the subsurface conditions, the logs of the test pits should be reviewed. NELSON GEOTECHNICAL ASSOCIATES, INC.