2009-10-06_REPORT - C1982056 - Laserfiche WebLink

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rthWest Colorado Consultants. Inc. Geotechnical / Environmental Engineering • Materials Testing October 6, 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, As requested, NWCC, Inc. (NWCC) has prepared this report outlining our observations made during the third quarter of 2009 at the Refuse Pile, which is located at Twentymile Coal Company's (TCC) Foidel Creek Mine in Routt County, Colorado. During this quarter, Brian Len and Tim Travis of NWCC visited the project site on September 28, 2009 to provide our quarterly inspection/observations. In addition, a representative of NWCC visited the refuse pile on August 3 and September 9, 2009 to take compaction tests in Area 4. A total of eight compaction tests (#422 to #429) were taken in Area 4 during these visits. 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. At the time of our site visit on September 28, 2009, we completed a cursory site inspection of the pile. Based on our observations made during this visit, it appeared that the contractor was presently stockpiling the refuse coal in Area 4 of the pile. 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. It should be noted that the internal roadways in the pile, as well as the haul road were in very good condition. 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 wash plants had produced approximately 118,700 tons of waste coal during the month of July 2009: approximately 102,650 tons during August 2009: and approximately 115,500 tons (970) 879-7888 • Fax (970) 879-7891 2580 Copper Ridge Drive • Steamboat Springs, CO 80487