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(��otcchnical l�{ncinccrin� Rc��uri <br /> Sin��lc-Pmnil�' I.�,si�lcncc <br /> C•��crctt, Washington <br /> Dcccmbcr�. 200> <br /> CG Pil� Nu. 2U17 <br /> Pagc 3 <br /> Gcolohy <br /> Most uf tl�c Pugrt Sound Rcgion �ca� al Ccctcd hy p,ist intrusion uC contincntal elaciutiun. 'I hc last period <br /> , uf glaciation, Qie Vashon Stade of the Frascr Glaciation, ended approaimately I 1,000 years ago. Many of <br /> U�e geomorphic features secn today are a result of scouring and ocemding by glacial ice. During Uie <br /> IVashon Stade, much of the Puget Saund region was overridden by over 3,000 fect of ice. Soil la}crs <br /> o��erridden by the ice shect wcre compacted to a much greatcr extent than those that �vere not. <br /> Thc gcologic unit mapped for this arca is sho�m on thc Gcolosic �1�n of thc li�crctt Z�-\tinutc <br /> puadran[;lc Snohomish Countv. Washineton, by James P. Minard (USGS 195�). Thc sitc is sho�ec !o bc <br /> undcrlain by glacial till or ad��ance outwash. Glacial till consists of an assortment of sand, silt and gravel <br /> depositcd at thc leading edge of the advancing glacier. Advance ouhvash is the sediment deposited by <br /> mclhvater strcams from the advancing glacier. This sediment typically consists of sand and gravel, but <br /> may contain laycrs of silt or clay. Our ;itc c.eplorati�ns cncountcrcd matcrial that ���c hacc characrerixed <br /> � <br /> � as advancc oiu�vash. <br /> I Explorations <br /> Subsurfacc cunditions ��'crc c�plorcd at Ihc srtc un Nu:cmhcr 23 and 3S, 2005, by r.�c�ca[in� a total uf <br /> � four test pi[s, hvo hand pils, and rivo Dynamic Cone Penetrameter Tests. "the test pits and hand pits were <br /> excavated to depths of 3.0 to 7.5 fcet below the ground surface. The explorations were located in the field <br /> by a representative from this tirm ��•ho also ezamined the soils and geologic con_'i:ions encountered, and <br /> Imaintaincd logs of the test pits. The approximate location, of the explorations are sho��m on the Site Plan <br /> in Figure 2. The soils were visually classificd in ecncral accordancc ��ith thc Unified Soil Clas�ification <br /> �, System, a copy of which is presented as Figure +. <br /> The hand pits ���cre explored using hand tools to dcpths ranging lrom 3.0 to 3.� fect. Samplcs �cerc <br /> obtained for the different soils encountcred. Thc hand pi;logs are shown in Figure 4. <br /> The Dynamic Cone Penetrometcr Tests (DCPTs) consistcd of driving a 10-square-centimcter poinl using <br /> a 35-pound hammer falling 15 inches. The standard mediod is to rewrd the blows for each 10 <br /> centimetcrs of pcnetiation. A computer program converts the counts into the Standard Penetratioa <br /> I <br /> Resistancc hlow cuunt or "N-���lue" (units: bla«�s per fuot). Piguns > and C prescnt the results of the <br /> � DCP"fs. <br /> � Cornerstone Geeiechnical, Inc. ��ZS <br />