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LJ <br />• <br />u <br />rolling topography in outcrop. The formations dip at ap- <br />proximately two to five degrees to the north-northeast. <br />colluvial soils generally cover the bedrock formations <br />to varying depths. Thicknesses of up to approximately 100- <br />feet were encountered during our field exploration Grogram; <br />however, lesser thicknesses, on the order of five to twenty <br />feet, are generally more typical, particularly on the more <br />steeply inclined slopes. These soils are generally silty to <br />sandy clays with gravel and cobbles (I•iL in the Unified Soil <br />Classification System, Plate A-1). <br />The colluvial soils that outcrop in the large cut above <br />the diversion channel (above the fan level) were investigated <br />in more detail during the recent studies. Three test pits <br />(TP-1 through TY-3) were excavated and two borings(B-1 and <br />B-2) were drilled in these deposits. <br />The purpose of this investigation was to assess the geo- <br />morphic character of these soils; specifically, the investi- <br />gation was to show whether the soils comprise an old land- <br />slide sediment. The test pits were excavated close to the <br />rock-soil contact and examined in detail for any signs of old <br />deformations (slickensides, etc.). <br />lde feel that the deposits do not comprise an old land- <br />slide as they have a distinct character of soils deposited <br />either by gravitational processes, or more probably, by a <br />short transport by wa[er. It appears that their classification <br />as colluvial soils is not accurate; their thickness is too <br />excessive and they carry numerous, partly subangular boulders <br />of young volcanic rocks that show clear signs of a short <br />transport. <br />We beliove,r.herefore, that the soils comprise the fill <br />- 6 - <br />~eornoQOCa+winH~.wc. <br />