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o c.onsuitants. inc Geotechnical /Environmental Engineering • Materials Testing ~/+E, V vD July 3, 2007 UV` Q 61p01 Twentymile Coal Company ~eotacna~tpP' 29515 RCR #27 D`v`SOO of C gatetY Oak Creek, CO 80467 Msntn9 ao Attn: Mr. Jerry Nettleton Job Number: 99-3983 Subject: Quarterly Observation Report, Refuse Pile, Foidel Creek Mine, Routt County, Colorado. Mr. Nettleton, As requested, NWCC, Inc. has prepared this report outlining our observations made during the second quarter of 2007 at the Refuse Pile, which is located a[ Twentymile Coal Company's (TCC) Foidel Creek Mine in Routt County, Colorado. During this quarter, we visited the project site on June 1 and June 29, 2007 [o provide our quarterly inspection/observations. In addition, we visited the refuse pile on June 1, 2007 to take compaction tests in Areas 2 and 2'/z. Six compaction tests (#348 to #353) were taken on June 1, 2007. 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 aze 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 visits on June 1 and June 29, 2007, we completed site inspections of the pile. Based on our observations made during this visit, it appeared that the contractor was presently stockpiling the refuse coal in Areas 2 and 2 t/z of the pile. It should be noted that they had also placed the first lift of refuse coal in the north east end of Area 3 at the time of our visit on June 1, 2007. The surface drainage conditions generally appeared to be adequate 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. As suggested, the water levels in the monitor wells installed on October 23, 1997 and December 9, 1999 were measured during this quarter on a monthly basis. A table and graphs showing the monthly water levels are attached. We were advised that the mine had produced approximately 26,903 tons of waste coal during the month of April 2007: 27,719 tons during May 2007: and approximately 23,334 tons during June 2007. It is our understanding that the fines being produced at the wash plant, which consists of 10 to 20 percent of the total materials being produced, aze being pumped underground into the mine. (970) 879-7888 • Fax (970) 879-7891 2580 Copper Ridge Drive • Steamboat Springs, CO 80487