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orthWest Colorado Consultan <br />Geotechnical / Environmental Engineering • Materials Testing <br />July 9, 2009 <br />Twentymile Coal Company <br />29515 RCR #27 <br />Oak Creek, CO 80467 <br />Attn: Mr. Jerry Nettleton <br />Job Number: 99-3983 <br />Subject: Quarterly Observation Report, Refuse Pile, <br />Foidel Creek Mine, Routt County, Colorado. <br />Mr. Nettleton, <br />As requested, NWCC, Inc. has prepared this report outlining our observations made during the second <br />quarter of 2009 at the Refuse Pile, which is located at Twentymile Coal Company's (TCC) Foidel Creek <br />Mine in Routt County, Colorado. During this quarter, we visited the project site on June 30, 2009 to <br />provide our quarterly inspection/observations. In addition, we visited the refuse pile on April 3, May 28 <br />and June 29, 2009 to take compaction tests in Area 4. A total of eleven compaction tests (#411 to #421) <br />were taken in Area 4 during these visits. All of the tests taken met the minimum compaction requirement <br />of 90% of the maximum standard Proctor density. Copies of the compaction test results and the daily field <br />report are attached. It should be noted that the abbreviations given in the Nuclear Density Test Results <br />(Proctor Data) are as follows: Maximum DD = Maximum Dry Density and OMC = Optimum Moisture <br />Content. Both of these values have been determined in accordance with ASTM D698. <br />At the time of our site visit on June 30, 2009, we completed a cursory site inspection of the pile. Based on <br />our observations made during this visit, it appeared that the contractor was presently stockpiling the refuse <br />coal in Areas 2, 3 and 4 of the pile. <br />The surface drainage conditions generally appeared to be adequate across the top and sides of the pile. It <br />should be noted that at the time of our visit, we did not observe any signs of instability, structural weakness <br />or hazardous conditions at the pile. It should also be noted that the roadways throughout the pile were in <br />much better condition than at the time of our last site visit in March. <br />As suggested, the water levels in the monitor wells installed on October 23, 1997 and December 9, 1999 <br />were measured during this quarter on a monthly basis. A table and graphs showing the monthly water <br />levels are attached. It should be noted that well 4MW was damaged/buried during movement of topsoil on <br />the refuse pile. It is our understanding that a permit revision will be submitted to eliminate the monitoring <br />at this well site. However, the water levels in the remaining four monitor wells will continue to be <br />measured on a monthly basis. <br />(970) 879-7888 • Fax (970) 879-7891 <br />2580 Copper Ridge Drive • Steamboat Springs, CO 80487