2009-02-09_REPORT - C1982056 (2)

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North West Colorado Consulta Geotechnical ! Environmental Engineering • Materials Testing January 7, 2009 Twentymile Coal Company 29515 RCR #27 Oak Creek, CO 80467 Attn: Mr. Jerry Nettleton Job Number: 99-3983 Subject: Quarterly Observation Report, Refuse Pile, Foidel Creek Mine, Routt County, Colorado. Mr. Nettleton, RECEIVED F EB 0 9 2009 %JIVIJ?V 1, U, reclamation, Mining and Safety As requested, NWCC, Inc. has prepared this report outlining our observations made during the fourth quarter of 2008 at the Refuse Pile, which is located at Twentymile Coal Company's (TCC) Foidel Creek Mine in Routt County, Colorado. During this quarter, we visited the project site on December 29, 2008 to provide our quarterly inspection/observations. In addition, we visited the refuse pile on November 7, 2008 to take compaction tests in Areas 2 through 3%. Six compaction tests (#396 to #401) were taken on this date. All of the tests taken met the minimum compaction requirement of 90% of the maximum standard Proctor density. Copies of the compaction test results and the daily field report are attached. It should be noted that the abbreviations given in the Nuclear Density Test Results (Proctor Data) are as follows: Maximum DD = Maximum Dry Density and OMC = Optimum Moisture Content. Both of these values have been determined in accordance with ASTM D698/AASHTO T99. At the time of our site visit on December 29, 2008, we completed site inspections of the pile. It should be noted that the majority of the pile was covered with 6 to 12 inches of snow at the tune of our site visit. Based on our observations made during this visit, it appeared that the contractor was presently stockpiling the refuse coal in Areas 2 to 3 1/, of the pile. We also observed that a separate subcontractor was removing the snow from the north end of Area I and beginning to place the soil cover materials at the northeast corner of Area 1. The contractor was excavating the soils cover materials from a borrow area located west- southwest of the refuse pile. The surface drainage conditions generally appeared to be in very good condition across the top and sides of the pile. It should be noted that at the time of our visit, we did not observe any signs of instability, structural weakness or hazardous conditions at the pile. However, as noted before the majority of the pile was covered with 6 to 12 inches of snow, which somewhat limited our observations of the surface materials. (870) 879-7888 • Fax (970) 879-7891 2580 Copper Ridge Drive • Steamboat Springs, CO 80487