3431 NASSAU ST 2018-01-02 MF Import

04/14/04 07:15 FAX 4253476588 C99A EyERL71' Q 009/032 Geolol'ic lmvertignirnn mul (icnteclinical Cneineerin¢Itatxrrt 00-02-20 NI: Comer 35" St. and Nassau St. Evercit, Washhaglon developed following the Unified Soil Classification torinat. A copy of this format is contained in Appendix 1 of this report in general, good correlation exists between the soil found underlying this site and that mapped on the surficial geologic map of the area. However, due to the depth of fill found over the southern portion of the site, the contact between the fill and the underlying natural soil was not observed in this area. The actual depth, declination and condition of this contact is unknown. The recommendations contained in this report reflect this unknown parameter. Due to the inherit variability of the shallow subsurface soil found below this site, the actual subsurface soil profile at any one location may vary somewhat from those described on the logs and from the interpretations and correlation's made herein. Based on the limited site data, it appears that the site is underlain at depth by 'transitional Beds (Qtb) or the structural equivalent Whidby Formation (Qw) as shown on the 1976 geologic niap of the site area. The basal Transitional Beds (Qlb) consist of dense, gray brown to blue gray, damp to moist, sandy silt to silt. The soil may contain small lenses of very fine- grained sand. This soil was found approximately two and one-half (2-112) feet below ground surface elevation at approximate elevation el 172.5. and is considered bearing soil for foundation support. This nasal soil was covered with up to 20 feet of uncontrolled till across most of the site. The uncontrolled fill contains concrete, asph•ilt, rock, stumps, lumber, glass, metal and paper. The origin of the uncontrolled fill is unknown. 3,4 Liquefaction Potential The project site is located within the Puget Sound Lowland Physiographic Province, a seismically active region with historic occurrences of earthquakes and other seismic actions. Liquefaction refers to a Phenomenon in which a saturated, loose, cotiesionless soil looses strength during an earthquake — allowing it to move vertically and/or laterally. The movement of liquefied soil can effect man made improvements and the general behavior ol' a structure in the area during a seismic event. The potential for soil liquefaction is dependent upon several factors GES, Inc.