10105 19TH AVE SE Geotech Report 2018-01-02 MF Import (2)

i i KA No. 092-06160 Octobcr 25,2006 Page 2 Gcoloelc SettinE The site lies within the central Puget Lowland. Thc lowland is part of a regional north-south tretiiding trough that extcnds from southwestern BrilisU Columbia to neur Eugene, Oregon. NoRh of Olympia, Washington, this lowland is glacially carved, witlt a depositional and erosional history including at least fo�lr separate glacial advances/retreats. Thc Pugct Lowland is bounded to the west by the Olympic Mountains and to the east by the Cascade Rangc. The lowland is filled with glacial and nonglacial sedimcnts consisting of interbedded gravet,sand,silt, till, and peat lenscs. 1'he Washington Division of Geology and CaRh Resourecs, Misccllancous Ficld Studies Map MP-1541, �! Geologic Map of The Edmonds Edmonds Fast and Part of 'I'he Edmonds West Quadrangles, Washington, indicales that the prope�ty is located in an area that is predominantly underlain by Vaslion I Glacial Till. Thc Vashon Glacial Till is typically characterized by an unsorted, nonstratificd mixture of clay, silt, sand, gravcl, cobbles and boulders in variable quantities. The Vashon Glacial Till is lypically dense to very dense and relatively impermcablc. 'i Ftcld InvcsHeation A ficld investigation consisting of excavating and sumpling two exploratory test pits that provided gencral covcrage of?he property to be developcd was complctcd to evaluate the subsurface soil and groundwatcr conditions. Thc exploratory test pits were eYcavatcd to approximatcly 5.5 feet below existing sitc grades. Norihwcst Excavating & Trucking, Ine. (a Krazan subcontractor) performed the excnvation work on October 6, 2006. The exploratory test pits were excavated with a Hobcat 120 Trackhoe. Represenlativc samples of thc subsurface soils encountcred in the test pits werc collectcd and sealed in plastic `:ags. Thcse samples were transporied to our Woodinville offiee for 30 day storage. The excavated soils wcre continuously examined and visually classified in accordanec with lhe Unificd Soil Classification Systcm(USCS). Soil Profile and Subsurface Conditions Thc subsurfacc conditions encountered within thc shallow exploratory tcst pils appcar to be typical of thosc encountered in die geologic region of the sitc. Soils cncountcrcd within the two explorarory test pits ('Pest Pit 1'P-1 and 1'est Pit TP-2) consistcd of approximately 2.5 to 3.5 feet of loose to medium riense, silty fine to coarse grained sand with variablc amounts of debris (Fill). 7'he fill soil is undedain 6y medium dense to dense, fine to coarse grained sand wilh variablc amounts of silt and gravel (Glacial 'Cill). 'Cbis material was encounrered down lo thc termination dcpth of the test p:ts (approzimately 5.5 feet bclow existing grades). Groundwatcr The cxplcratory test pits were checked for the presenec of groundwater during and immediately following tiie excavation operations. Groundwater was not encountcrcd in the explorarory test pits at the time of our cxploration. It sltould be recognized tliat �vater tabte elcvations may fluctuatc with time. 'I7te grouadwater level will be dependent upon seasonal precipitation, irrigation, land usc, and climatic conditions, as well as other factors. 7'herefore, water levels at the time of thc ficld invcstigation may be diffetent from those Krezan&Assoclatn,Inc. � Offices Swing'Ihe`Ncstem Unitcd Stetes I f �i