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1 ,W,h,21, �� � Northern, ►��. <br /> Proj.et No.2se-aa <br /> � The wbsurface waditions observed in Teu Pit#3 �nsistad of approximately <br /> o�(1)foot t6ick layer of 1 'h inch minus crushed rock underlain by uncoovdlcd fill(with <br /> � abundant organics and coasauction debris)to a dapth of four(4)feet bgs. Aa old wpsoil <br /> laya and was encountercd to a depth of approximately five(5)feet bgs. A silty saod(SIvn <br /> was obsmed underlying the old topsoil to a depth of approximately six and one-half(6 �i4) <br /> � feet bgs. 'fhis silry saad is brown in color and exhibited medium dease coasisteney. A SaY <br /> to brow0.dense, sandy gravel(GP)was observed below the sihy sand w the ter�nination <br /> depth of the test pit(approximately 9.5 feec bgs). <br /> � For detailed tat pit and boring logs, please rofer to Appendix B. <br /> I4.2.3 Grouadwater <br /> � � Heavy ground water seepage was mcountered in all of the test pits and tat boring at <br /> ' apProximately seven and one-half(7 �b)fat to aght(8)feet below the acis�ng ground <br /> wrface. This groundwater appesrs to represent the regional groundwater table within the <br /> sand and sandy gravel layus encountered in the test pits and test boring at a depth of betwan <br /> ( 7.5 to 8 feet bgs. <br /> . f �.3 Pu6lished Geo/ogy <br /> � - Smith(1976)has mapped the geology of the site� as artificial fiq and Quatamary <br /> ' � Vaslwn Tiil(Qvt). The aative sihy sand oburved in Test Boring#1 at a depth of <br /> approximat�ly fourteen(14)feet bgs wrrespoads welt with the mapped ciassificatio�of the <br /> Vashon Till(Qvt). Howeva,the narive sand and gravelly soiis obsecved at the site overlying <br /> � � the tiil coaespond with the classification of glacial outwash deposits(recessional)of the <br /> Vashon DriR(Qvr)• <br /> � 5.0 CONCLUSIONS <br /> We conclude that the site is geotechaically witable for the development of the <br /> � proposed project provided that our geotechnical recommendations are followrod dwing the <br /> desiga ar►d coaswccion phases of the pmject. <br /> � The site is undulain by a variable thickneu of uacontroUed fill,organic�oils snd <br /> loose native soils. The rewlts of our field investigation show that an adequate baeing soil is <br /> present at approximately seven and onahalf(7 'h)fea bgs in the area o�Test Pit#1,at <br /> � approximately one(1)foot bgs in the area of Test Pit#2,and approximately five(S)feet bgs <br /> in the azea of Test Pit#3 and Test Boring#1. Thae bearing soils ate witable for tlu�pport <br /> of rngineered loads designed for a maximum safe beariag capacity of 2000 psf. <br /> � The vay dense sandy gravel and silty sand observed at approximately 6ve(5)&et bgs <br /> ' and approximately fourtan(14)feet bgs respectively are witable as bearing aoils for the <br /> proposed UST's. <br /> � 15miM, M., 1976, Prdiminary Surficial Geabgk MaD of Ne Muldltco and Everett Qu�dranOks. <br /> Snohomish County,Washinqton,MaD GM 20. <br /> r 4 � <br />