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i; sss III IIIIII~IIIII~ III West Colorado Consultants, Inc. Geocechnical! Environmental Engineering • Materials Testing - RECE! V` L August I I, 2001 Twentymile Coal Company AUr7 `~ Q 2001 29515 RCR #27 Oak Creek, CO 80467 Division oJh{ntarals 6 Oeo,c; Attn: Mr. Rick Mills Job Number: 99-3983 Subject: Quarterly Observation Report, Refuse Pile, Foidel Creek Mine, Rnutt County, Colorado. Ladies & Gentlemen; As requested, NWCC, Inc. (Notthwest Colorado Consultants, Inc.) has prepared this letter outlining our observations made during the second quarter of 2001 at the Refuse Pile, which is located at the Foidel Creek Mine in Routt County, Colorado. During this quarter, we visited the project site on May 31 and June 14, 2001 to test the compaction of the materials being placed and compacted, as well as to provide our quarterly observations. At the time of our site visit on May 3 I, 2001, we conducted six (ti) compaction tests (# 195 to #200) across the portion of the refuse pile in which the compacted lift had been placed in Area I. A copy of the compaction test results and daily report are also attached. Based on the compaction test results, it appears that the fill materials are being placed and compacted in general accordance with the project specifications. It should be noted that the abbreviations given in the Nuclear Density Tes[ 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 June 14, 2001, we met with Mr. Rick Mills and Dave Wallace of Twentymile Coal Company to observe the conditions at the Refuse Pile. At the time of our visit, we observed that the majority of the refuse materials (waste coal) were being stockpiled and placed in Area 1. We also observed that the client had removed the majority of the previously stockpiled materials from the south end of the refuse pile and had exposed the underlying, natural clays. During this visit, we also observed some seepage and standing water along the toe of the embankment at the north end of the refuse pile. We recommended that the areas in which the standing water was observed be regraded so that the seepage is not allowed to pond at the toe of the slope. It should be noted that the east face of the refuse pile was dry and we did not observe any seepage or wet areas along this face of the embankment at the time of our visit. We were advised that they had produced approximately 27,100 cubic yards of waste coal in April; approximately 22,200 cubic yards in May and approximately 9,200 cubic yards in June. (970) 879-7888 • Fax (970) 879.7891 2580 Copper Ridge Drive, P.O. Box 775226 • Steamboat Springs, CO 80477