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i <br /> <br />• <br />Purpose and Scope of Study <br />This report presents the results of a geotechnical evaluation for the slope failure situated to the east and <br />northeast of Pond 16 at the Seneca H W Mine. The site is more specifically located in Section 26, Township 5 <br />North, Range 88 West in Routt County Colorado. The approximate location of the project site is shown in <br />Figure # 1. <br />Field exploration programs were conducted to obtain general information on subsurface conditions <br />encountered at the site. Material samples obtained during the subsurface investigations were tested in our <br />laboratory to provide data on the classification and engineering characteristics of the on-site soils and bedrock <br />materials. The results of the field and laboratory investigations are presented herein. <br />This report has been prepared to summarize the data obtained and to present our conclusions and preliminary <br />recommendations for stabilizing and/or reconstructing the failed slope. <br />Site Conditions <br />The subject site is located in the southwestern end of the Seneca IIW Mine and the ramp for the reclaimed <br />surface mine is situated several hundred feet east of the subject slide area and Pond 16A. A site plan showing <br />the existing features, as well as the approximate location of the test holes and test pits that were advanced <br />within the slide area (Test Holes 1-6 and Test Pits 1-5) and the test holes drilled outside of the slide area (Test <br />Holes 7-11) are shown in Figure #2. <br />The subject slide is located to the east and northeast of Pond 16 and northwest and west of Pond 16A. Based <br />on our discussions with Jay James of Peabody and our review of the available aerial photographs and <br />topographic surveys provided by the client, it appears that the construction of Pond 16 and the haul road that <br />previously crossed the failure was completed in August 2000; whereas, Pond 16A was constructed in the <br />summer of 2004 to provide additional sedimentation storage capacity, as the mined areas to the east were <br />expanded. The portion of the haul road that crossed the slide area was reclaimed in 2007 by the placement of <br />additional fill materials along the uphill side of the existing roadway alignment. It is our understanding that <br />the subject slope failure was first observed in the spring of 2008; however, based on our review of the aerial <br />photograph taken in 2004, it appears that a scarp is located at the southwest end of the failure area and between <br />the pond and haul road in an undisturbed area. <br />Job Number: 08-8099 Nwcc, Inc. Page 2