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.~ Geotechnical I Environmental Engineering • Materials Testing Jnly 7, 2006 Twentymile Coal Company 29515 RCR #27 Oak Creek, CO 80467 RECEIVEp Attn: Mr. Jerry Nettleton JUC Job Number: 99-3983 2 ~ 2006 Vision ofryinera/S ~ OeologY Subject: Quarterly Observation Report, Refuse Pile, Foidel Creek Mine, Routt County, Colorado. Dear Mr. Nettleton, As requested, NWCC, Inc. has prepared this report outlining our observations made during the second quarter of 2006 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 April 17, May 22 and June 26, 2006 to test the compaction of the processed waste coal being placed in Areas 2 and 2 lh. We also visited the project site on June 3Q 2006 to provide our quarterly inspection/observations. At [he time of our site visit on April 17, 2006, we took 4 compaction tests (#307 to #310) in Area 2i/z of [he refuse pile and 5 compaction tests (#311 to #315) in Area 2 of the refuse pile. At the time of our site visit on May 22, 2006, we took 4 compac5on tests (#316 to #319) in Area 21/z of the refuse pile. A[ the time of our site visit on June 26, 2006, we took 4 compaction tests (#320 to #323) in Area 2'h of the refuse pile and 4 compaction tests (#324 to #327) in Area 2 of the refuse pile. 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/AASH1'O T99. At the time of our site visit on June 30, 2006, we completed a site inspection of the pile. Based on om observations made during this visit, it appeared that the contractor was presently stockpiling the refuse coal in Areas 2 and 2'/z. The surface drainage conditions appeared [o be adequate across the top of the pile. At [he 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 [he 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 aze attached. (970) 879.7888 • Fax (970) 879.7891 2580 Copper Ridge Drive • Steamboat Springs, CO 80487