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SITE CONDITIONS AND GEOLOGIC SETTING <br />The project site is located approximately 1 mile west of Routt County Road 27 in the southern portion of [he • <br />Yoast Mine area. The project site was vacant at the time of this investigation and was generally weU vegetated <br />with weeds, grasses, scrub oak brush and other miscellaneous deciduous brush. Aspen trees also line the west <br />side of the drainage. An existing stock pond, which consists of an 8 to 10 foot high eazthen embankment, was <br />observed several hundred yards upstream of the project site. The pond appeared to be at least several feet deep <br />and an overflow spillway had been constructed for the pond along its east side. However, the spillway did not <br />appear to have had received any flow recently. <br />The proposed embankment will be constructed within a small, umamed seasonal drainage which generally <br />drains down to [he southeast into the Grassy Creek drainage which is located just south of the project site. The <br />drainage generally slopes down to the southeast on [be order of 10 percent in the vicinity of the project site and <br />was not flowing at [he time of this investigation. <br />The project site is located within a relatively small drainage which is bordered on both the southwest and <br />northeast by steep to very steep natural slopes which slope down into [he drainage on the order of 35 [0 60 <br />percent. The drainage is deleted by [he surrounding ridge lines and a well detmed channel was not observed. <br />Sandstone bedrock outcrops were observed northeast and southwest of the proposed pond site and the outcrops <br />appear to be dipping steeply to the east-southeast. The topography of the pond site is somewhat variable and • <br />generally slopes moderately down the drainage on the order of 10 percent. A maximum elevation difference of <br />approximately 25 Feet exists across the pond and embankment sites. <br />Regional geologic mapping indicates that the near surface bedrock underlying the project site consists of <br />interbedded sandstones, shales and coal of the Cretaceous Iles and Williams Fork Formations. These Mesozoic <br />sedimentary beds also display a steep dip to the east and southeast and mapping indicates the site is along the <br />west Rank of a syncline structure. <br />FIELD INVESTIGATION <br />The field investigation for the project was conducted on May 5, 1997. Seven (7) test holes were drilled a[ the <br />approximate locations shown on Figure #2 to explore the subsurface conditions. Locations of the test holes <br />were determined by pacing from features as staked by the client. The elevations of the test holes were <br />determined by interpolating between the contours shown on the site plan provided by the client. <br />The test holes were advanced through the overburden soils and bedrock with atrack-mounted CME 45 drill rig <br />utilizing flinch diameter continuous flight power augers. The test holes were logged by a representative, of <br />Northwest Colorado Consultants, Inc. <br /> <br />]ob No. 97-3(p0 Northwcs~ Coloratlo Consultan~s, Inc. Page ? <br />