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<br />I ~ Foidel Creek Mine in Routt County, Colorado. The site was vacant at the time of our investigation. The <br />site was vegetated with grasses, weeds and sagebrush. <br />The topography of the site is variable and generally consists of rolling hills. The topography at the Intake <br />Shaft Pad slopes gently down to the northwest on the order of 3 to 5 percent. A seasonal drainage is <br />located to [he north of the shaft pad site. <br />Subsurface Conditions: To investigate the subsurface wnditions at the site, two test holes were advanced <br />at the shaft pad site and four test holes were advanced along the proposed access road on November 21, <br />2003 with anal!-terrain drill rig utilizing 4-inch diameter continuous flight power augers. The <br />approximate test hole locations aze shown in Figure #2. <br />The subsurface conditions encountered were variable and generally consisted of a layer of topsoil and <br />organics overlying natural clays and claystone bedrock to the maximtun depth investigated, 18 feet. <br />Graphic logs of the exploratory test holes are presented in Figure #3 and the associated Legend and Notes <br />are presented in Figure #4. <br />A layer of natural topsoil and organics was encountered at the ground surface in all of the test holes and <br />was approximately 3 to 6 inches in thickness. Natural clays were encountered below the layer of natural <br />topsoil and organics in all of the test holes and extended to depths of 4 to 7 feel The natural clays were <br />slightly sandy, moderately to highly plastic, stiff to very stiff, slightly moist to moist and brown in color. <br />Samples of the natural clays classified as CL to CL-CH soils in accordance with the Unified Soil <br />1 Classification System. claystone bedrock was encountered below the natural clays in test holes 5 and 6, at <br />a depth of 7 feet, and exended to the maximum depths investigated. The claystone bedrock materials <br />were nil to sandy, fine-grained, hard to very hard, moderately to highly plastic, slightly moist to moist and <br />brown to gray in color. Samples of the claystone bedrock classified as CL to CH soils in accordance with <br />the Unified Soil Classification System. <br />Swell-consolidation tests conducted on samples of the natural clays and claystone bedrock indicate that <br />the materials tested will exhibit a moderate to high swell potential when wetted under a constant load. <br />The swell-consolidation test results are shown in Figures #5, #6 and #7, and all of the other laboratory test <br />results are summarized in Table 1. <br />Groundwater seepage was not encountered in the lest holes ai the time of drilling or when measured 4 <br />days after drilling. However, it should be noted that the groundwater conditions at the site can be <br />expected to fluctuate with changes in precipitation and runoff. <br />Roadway Gravel Section Recommendations: It is our understanding that the new access road will <br />generally be subjected to low traffic volumes typically consisting of pickup wcks with occasional <br />delivery/haul woks during conswction of the shaft or support structures. Therefore, we have assumed an <br />18-kip equivalent single axle loading (ESAL) of 3,000 for the access road. Based on the field <br />A investigation and laboratory test results, we have correlated a soils resilient modulus of 5000 psi for the <br />on-site materials. <br />lob Number: 03.3838 IJWCC, Inc. Page 2 <br />