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CASCADE GEOTECHNICAL INC. <br />June 2, 1994 <br />Job No. 9405-02G <br />The DCPT logs provide a continuous profile of the consistency of the soils with depth. <br />Interpretation of the DCPT data was done in accordance with guidelines contained in Triggs and <br />Simpson (1992)1. <br />The soil conditions within the proposed Wetland Mitigation Area consisted of variably thick <br />layers of uncontrolled fill overlying glacially consolidated soils. Soils encountered in the <br />proposed building and paved areas located at the northern portion of the site, generally consisted <br />of a thin layer of forest duff overlying variably thick layers of weathered and unweathered <br />glacially -derived soils. <br />The traruhoe test pits excavated within the proposed wetlands mitigation area showed <br />uncontrolled fill comprised of brown to blue -gray, silty fine-gralied sand with some gravel, <br />occasional cobbles, and organics to depths ranging between seven and one-half (7 'A) and nine <br />(9) feet. A layer of buried wood and logs was observed in all of the test pits between depths <br />of six (6) and seven (7) feet. <br />The test pits also showed native soils underlying the uncontrolled fill. These soils consisted of <br />blue -gray to brown -gray, silty very fine to medium -grained r A (SM), and medium -grained sand <br />(SP), that was medium dense to very dense, and wet to sa sled. <br />DCPT/MSS Test Borings Ml through #5, conducted within the proposed pavement and building <br />areas, showed a thin layer of forest duff overlying native, glacially -derived soils. Each of these <br />test holes showed glacial till soil comprised of gray to brown, mottled, moist silty sand with <br />some gravel (SM) to a maximum depth of three and one-half (3 1/2) feet as shown by <br />DCPT/MSS #3 and k5. Weathered horizons of the glacial till were observed to be loose to <br />medium dense, while the unweathered till was dense to very dense. DCPT/MSS #1 and #2 were <br />terminated within this soil unit. <br />`Triggs, J.F., and Simpson, P.D., 1992, "A Portable Dynamic Penetrometer for <br />Geotechnical Investigations": Unpublished Technical Paper <br />5 <br />