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Afield exploration program was recently conducted to obtain general information on subsurface conditions <br />encountered at the site. Material samples obtained during the subsurface investigation were tested in our <br />laboratory to provide data on the classification and engineering chazacteristics of the on-site soils and <br />bedrock materials. The results of the field and laboratory investigations aze presented herein. <br />This report has been prepared to summarize the data obtained and to present our conclusions and <br />preliminary recommendations for stabilizing and/or reconstructing the failed slope. <br />Site Conditions <br />The subject site is located several hundred feet east of County Road #37 and within the extreme western <br />edge of the Yoast Mine in Routt County, Colorado. A site plan showing the existing features, as well as <br />the approximate location of the test holes and test pits that were excavated within the slide area are shown <br />in Figure #2. <br />The subject slide is located to the north and northeast of Pond 12, which we understand was constructed in <br />1999. The failure area is located along a southwest facing slope situated immediately uphill of the pond <br />• and the drainage that flows into the pond from the east. The approximate limits of the slope failure are <br />shown in Figure #2. It is our understanding that a haul road was constructed along this slope as the pond <br />was being constructed. It is also our understanding that a considerable amount of site grading, consisting <br />of cuts on the uphill portion of the roadway and the placement of fill materials on the downhill side of the <br />roadway, was required during the construction of the haul road. It should also be noted that the haul road <br />site has since been reclaimed and additional fill materials were brought to the site to fill in the road cut <br />section as it was reclaimed. <br />Based on our observations, it appears that the head scarps for the slide are situated in the areas that were <br />reclaimed after the haul road was abandoned. The head scarps appear to range from approximately 500 to <br />550 feet in length and anywhere from 1 to 15 feet in height. The approximate location of the larger head <br />scarp is shown in Figure #2. The debris flow from the slope failure has encroached into the eastern and <br />northern sections of the pond. It is our understanding that some additional site grading has taken place in <br />this area since the original slope failure occurred to try and repair the slide. However, the previous site <br />grading does not appear to have mitigated the failure. Based on our observations, it appears that the failure <br />has increased in size since our first visit to the site in August of 2007. <br />A rip rap lined drainage channel that discharges into the pond is located east of the pond and south of the <br />. failed area. Water was observed to be flowing in the drainage channel in an east to west direction at the <br />Job Number: 07-7600 NWCC, Inc. Page 2 <br />