3505 SHORE AVE 2016-01-01 MF Import

Gaotxhnical Engineering Letter 3505 Shocc Avcnuc Deck Addition Everett,Washingcon May 26,2010 NGA File No. 827110 Page 3 to thc bottom of thc slope and awey Crom tL+e face of the stap alope, including the water collecud in the surface drains on yrour proptrty. SubsurfAce Condltlona Ceology: 7'he geologic units for this aiee aro shown on 1Le Diauibution and Descrintion of Geolomc Units. btuldlteo Ouadran 1�Washinetoa by James P. Minard (U.S.G.S., 1982). The siu is mapped aa Transitional Beds(Qtb). This unii is described az thick beds of clay, silt,and fine sand. Our enplorations generalfy encountered sand end silt deposiu consistent with the desaiption of the Transitional Beds. Exploratfons: Tlte subsurface conditions within the site were ezplored on Mey I1, 2010, in t6ree hand tool excevations ranging in dcpth from 4.0 to 7.5 feet below ''ae eaisting surface. Tho epproximau locations of our explorations are shown on Figure 2. An cngincer hom NGA was p�ssent during the explorations,examined the soils and geolopc conditions encounttred, obtained samples of the different soil types, and maintained loga of tLe explorations. T6e soils wae visually classified in general accordance with the Unified Soil Clessi6cation System,preseatad in Figure 4. T6e]ogs of our hand tool exploratioat are attachod to this Ictter as Figure 5. We preseat a brief summary of the subsurface conditions in the following patagraph. For a detailed description of the subsurface conditions,the boring logs should be reviewed. Each of the explorations exposed a surficial layer of loose, silty fine sand with abundmt organics extending to depth of 0.5 to 1.5 feet below t6e surface, which was inte�piUed as topsoil and 611. Below the topsoil and fill, eecb of the exploradons encountered loose to medium dense fine to coarse sand with silt and varying amounts of gravel extending dept6s of 4.0 to 7.0 feet below the surface. Below 7.0 foet, HA-1 near the planned dxk encounteted intecbedded dense sand and very stiff silt to the depth explored at 7.5 Cett. Hydrologic Conditions (:rvundwater sapage was not encountered within any of the explorations eztending to depUss of up to 7.5 fect below the adjacent ground surface. However, it is our opinion that a perched p+oundwater condition could develop on this siro during wotter times of thc year. Pe�hcd wata occucs when sudace water NELSON GEOTECHNICAL ASSOCIATES, INC. `l��p