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Geotechnlcal / EmArpnmental Engineering • Materials <br />10 Celebrating 20 Years of Service <br />1992 -2012 <br />October 1, 2012 <br />Peabody Energy <br />P.O. Box 670 <br />Hayden, CO 81639 <br />Attn: Mr. Roy Karo <br />Job Number: 08 -8099 <br />Subject: Site Observations and Slope Repair <br />Recommendations, Pit Ramp Slide, Seneca II -W <br />Mine, Routt County, Colorado. <br />Gentl6men: <br />As requested, NWCC, Inc. (NWCC) visited the Pit Ramp Slide situated NN7thin the Seneca II -W Mine in Routt County, <br />Colorado and has prepared this report to summarize our observations and recommendations. NWCC_ 's first visit to the <br />site was on July 7, 2011. Our second site visit was made on September 18, 2012, <br />Site Observations: At the time of our first site visit 3n July 7, 2011 we observed the conditions at the Pit Ramp Slide <br />site with Jill Carlson of the Colorado Geologic Survey '(CG`S); Sandy Brown and Susan Burgmaier of CoJorado <br />Division of Reclamatibt`i, Mining and Safety (CDRMS); find Dennis Bugay and Artil Ray of Peabody Energy <br />(Peabody). At the time of our visit, we observed a head scarp ranging from 3 to 5 feet in height situated at the uphill <br />side of the reclaimed pit ramp road. The head scarp appeared to be several hundred feet in length and running parallel <br />to the top of the previous road cut. Debris flow from the slope failure had encroached onto the existing access road <br />situated downslope of the failure'and towards the west end of the slide area. In the eastern half of the slide, the toe of <br />the debris flow was situated above the access road. The debris flow appeared to range from 2 to 5 feet in height and <br />water was observed seeping from the debris flow that had encroached onto the access road. NWCC was advised that <br />the previous road cut was filled in at the time the road was originally reclaimed and that several attempts have been <br />made to stabilize the failure by regrading the slide area. <br />At the time of our second visit on September 18, 2012, we visited the slide area with Marsha Talvitie of CDRMS and <br />Jay James of Peabody. At the time of this visit, we observed that two new surface drainage ditches had been <br />constructed across the failure areas. The ditches had been constructed in a V configuration and ranged from 2 to 3 feet <br />in depth. The ditches had been lined with Turf Reinforcement Material (TRM). The eastern most ditch is situated in <br />the central portion/midpoint of the slide area and the second ditch is situated near the western edge of the slide area. <br />The ditches angled down to the existing roadway in a southeast to northwest direction and discharged into the ditch <br />located on the uphill side of the access road. It should be noted that we observed undisturbed bedrock materials within <br />1 foot of the ground surface and in the base of rills located downslope of the debris flow toe in the eastern half of the <br />slide area. <br />(970) 879 -7888 • Fax (970) 879 -7891 <br />2580 Copper Ridge Drive • Steamboat Springs, CO 80487 <br />