1718 ENGLAND AVE 2016-01-01 MF Import

� Gcotcchnical Enginccring l�v:�luation England Avcnue Lot ' Jmic 2, 2005 NGA File No.41 ISOS Pagc 3 I mapped as Esper.mce Sand (Qe1. This unit is described as nuudium to coarse sand. WhiJbcy Formation � (Qw) and Vashon Till (Qvt) arc also mappcd ��car this site. Our esplontions generally encountercd sanJ � consisteut with the description of Esperance Sand. q Eaplur:�tions: Thc subsurfacc conditions within thc sitc wcrc cxplon�d on March 22, 2005 by drilling � four borings to depths r.mgino from 41.5 ro and 51.5 fect bclow the existing surface using a tr;�ck � mountcd limited :�ccess Jrill rig. The approximate locations of our esplorations are shown on Figure 2. A o�ologist from NGA ��as prescnt durin� thc cxplorations, cxamincd thc soils and gcologic conditions Ii�acountercd, obtained samplcs of thc differcnt soil types, and maintained logs of the explorations. A Standard Pcnctration Ter: (SPT) was performcd on each of the samples during drihing lo docwnent soil Idensity at depth. The SPT consists of driving a 2-inch outer-diameter, split-spoon sampler 18 inches using a 140-pound h.unmer with a drop of 30 in�hes. The number of blows requircd to drive the sampler Ithe linal 12 inches is referred to as the"N" value and is presentcJ on the boring lo��s. The N value is used to evaluatc tlie svength and density of thc deposit. IThe soils were visually classified in oener.�l accordance with the Unified Suil Classification System, Ipresented in �igure 4. Thc logs of our borings are attaclred ;o this report :md are prescntcd as Fivures 5 through 8. �Ve prescnt a bricf summary of thc subsurface conditions in the (ollo�ving paragrapns. For a Idetailcd dcscription of thc subsurfacc conditions, thc boring logs should bc rcvic�vcd. Boring I encountercd loose to dcnse, finc to medium sand with laycrs of vcry stiff to hard silt extending to 13 feet below the existing surface. Below 13 fect in Boring I, we encountered medium dense to veq� Jense sand extending to thc bottom of thc cxploration at d1.5 feet belo�v the surface. This soil was interpreted asthe Esperance Sand. II3orings 2, 3,and 4 encountered a thin I:ryer of organic topsoil overlying the�sperance sand deposit. Thc upper two to eight feet o(the sand was loose. Belo�v this loose zone, these borinas encountemd medium � dense or better native ti:lll(I (IC[1O51Iti CSlCO(III7�' IO lI1C �C(7(I15 CX�IOfC(I at 41.5 to 5 LS feet below the surface. All borings were tcrminated in thc Esperance Sand deposit. I NELSON GEOTECHNICAL ASSOCIATES, INC. I