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Geotechnical / Environmental Engineering • Materials Testing <br />Celebrating 20 Years of Service <br />1992-2012 <br />July 12, 2013 <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 Additional Slope <br />Repair Recommendations, Pit Ramp Slide, Seneca II- <br />W Mine, Routt County, Colorado. <br />Dear Roy, <br />As requested, NWCC, Inc. (NWCC) recently visited the Pit Ramp Slide situated within the Seneca II -W Mine in Routt <br />County, Colorado and has prepared this report to summarize our observations and recommendations. NWCC <br />previously prepared a Site Observations and Slope Repair Recommendations for this site under the above job number <br />and dated October 1, 2012. <br />Site Observations: As requested, NWCC visited the site on June 27, 2013 to observe the conditions at the Pit Ramp <br />Slide site. At the time of our visit, we observed that no apparent movement of the slide area has occurred since the <br />repairs were made in 2012 and our previous site visits. The repairs that were completed in 2012 consisted of the <br />installation of two surface drainage ditches that were constructed to collect and divert surface away from the upper <br />portions and face of the slide area. The ditches were constructed in a V configuration and ranged from 2 to 3 feet in <br />depth. The ditches had been lined with Turf Reinforcement Material (TRM). The eastern most ditch is situated in the <br />central portion/midpoint of the slide area and the second ditch is situated near the western edge of the slide area. The <br />ditches angled down to the existing roadway in a southeast to northwest direction and discharged into the ditch located <br />on the uphill side of the access road. <br />Recommendations: Based on our recent observations made at the site and our previous observations, it appears that <br />the slide area has stabilized. No apparent downslope movement was observed within the slide area or near the access <br />road that runs along the toe of the slide area. Based on the present condition of the slide area, NWCC does not believe <br />that the subsurface trench drains need to be installed at this time. NWCC recommends that the slide area be observed <br />for at least one more year. If future movement is to occur, it will most likely occur during next spring's snowmelt. If <br />movement is observed next year, then the subsurface trench drains should be installed as per our previous <br />recommendations. <br />(970) 879 -7888 • Fax (970) 879 -7891 <br />2580 Copper Ridge Drive - Steamboat Springs, CO 80487 <br />