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Gcotechnical Enginccring Report <br /> 51 17 23"� Ave W <br /> January 2, 2009 <br /> RMI File No. 50909 <br /> Pagc 2 <br /> 1. Review oeologic maps of the area and information in our files. <br /> 2. Perform a walk-through evaluation of existing geo'.:chnical, erosion and relative stability <br /> conditions at the site, including stcep slopes. <br /> 3. Provide a geotechnical report discussing our findings,opinions, and recommendations. <br /> EX'STING CONDITIONS <br /> Generai <br /> We reviewed the general geologic conditions of the site, which are shown on the Distribution and <br /> Description of Geologic Units in the Mukilteo Quadrangle, Washinb�ton by Minard, J. P. (USGS, 1982). <br /> The site area, slope profiles, observed conditions, existing features, and the recommended construction <br /> auproach are shown on the Site Plan(�igure 2)or the Schematic Cross-Section (Figure 3). <br /> Surface Conditions <br /> The site consists of a developed residential lot with an existing home. It is on the east-facing steep slope <br /> overlooking a deep erosion cha�nel, Narbeck Creek. A concrete slab behind the house was underpinned <br /> in .lanuary 2002. A wooden (railroad ties) retaining well is situated at the top of the steep slope about 6 <br /> feet from the rear concrete slab. The general site conditions, the schematic slope geometry and our <br /> interpretation of existing conditions within this area are shown on the enciosed Site Plan (Figure 2) or the <br /> Schematic Cross-Section in Pigure 3. <br /> Thc slope is at about 41 degrces and has many alders and some Inrge wniferous trecs on it. <br /> The Cross-Section was constnicted ;r�m mcasurements with a tape and digital level. <br /> Geologic Conditions <br /> Landfortns within this region comprise a :ystem of glacially sculptured features, which have been <br /> exposcd by post-glacial erosion. Tlic icrrain oi this area has been glacially modified, and the soils have <br /> been placed either prior to, or during the latest glaciation of the Puget Lowland area. Glacial ice last <br /> occupicd the region during the late Plcisrocene epoch, some 10,000 to 13,000 years before present. The <br /> latcst glacial advance over the arca is referted to as the Vashon Stade of the Fraser Glaciation, which <br /> deposited the glacial materials on site. <br /> R. 11 ASSOCIATES LLC �� ��`' <br />