1315 MADRONA AVE 2016-01-01 MF Import

G2otechnical Engineenng Report 1313 Madrona Avenue Evere[t, Washington March 11, 2013 RN File No. 27�3-00 � A Page 2 SITE CONDITIONS Surface Conditions The roughly rectangular shaped pro�ect srte �s about 1 acre in sre ane has maxirnum dimensions of approximately 120 feet in the east-west direction and 200 feet in tha nortf�.-south direction. Access to the site is provided by Niadrona Avenue to the scuth. Tne site is also bordered by existing residentiaf acreage to the east and west A layeut o( the sav is si�own on the Site Plan m Figure 2. The ground surface within the site is generally moderately sloping down to the north, untd approximately the last 30 feet where it drops steeply do�vn to the railroad tracks. A 6-foot high post ano lagging retaining wall is located at the bottom of the steep slope The slope is weil vegeiated wrth trees and bushes There was a moderate arnount of water running off the slope at the retaming wall. One smgle-famdy residence with outbuildmgs currently srts wrthin the s�te. The site is vegetated mostly with grass, with landsczped areas surrounding ihe existing residence. Geology tviost of the Puget Sound Region was affected by past intrusion of continental glaciation. The last period of glaciation, the Vashon Stade o` the Fraser Glaciation, ended approximately 14,OOG years ago. Many of the geomorphic features seen roday are a result o( scounng and overndu g by glacial ice. During the Vashon Stade, areas of the Puget Sound region were overr,dden by over 3,000 feet of ice Soil layers overridden by thc ice sheet were compac[ed to a much greater extent than those that were not. Part of a typical glacial sequence witfun the area or the srte includes the (ollowing sod depos:ts from newest to oldest Artificial Fill �afJ - Fill material is oiten locally placed by human activities, consistency will depend en the source oi the fill The th�ckness and expanse of U�is matenal wdl be dependent on extent of fill required to grade land to the desired elevaucns Densrty oi the fdl will depend on earthworl activiues and compaction efforts made during the placement of the matenal. Recessional Outwash (Qvr) - These deposits were derived hom the stagnat�ng and receding Vashon c�lac�er and consist ot mostiy of sUatif�ed sand and gravel, but indude unstra[died ablation and meli-out deposi[s Recessional deposits were not compacted by the glac�er and are rypically not as dense as those that were. Vashon Till (Qvt� - The till is a non-sorted mixture of clay. sand, pebbles, mbbles and boulders, all in variable amounis. The till was deposited directly by the ica as it advanced over and eroded uregular surfaces of prev�ously depos�ted formauons and sediments. The till was well compacted by the advancing glacier and exhibrts high strength and stabdity Drainage is considered very poor in the t�ll. Advance Outwash (Qva) - The advance outwash typically is a thick section of mostly clean, peb6ly sand vnth �ncreasmg amounts of gravel higher m the section The Robinson Nohle. Inc