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Geotechnical /Environmental Engineering RECEIVED JUN :0 q 2004. Division °f~Minerals and Geology Subject: Quarterly Observation Report, Refuse Pile, Foidel Creek Mine, Routt County, Colorado. Ladies & Gentlemen; April 6, 2004 Twentymile Coal Company 29515 RCR #27 Oak Creek, CO 80467 Atlas: Mr. Sandra White Job Number: 99-3983 As requested, NWCC, Inc. (Northwest Colorado Consultants, Inc.) has prepared this letter outlining our obscrvations made during the first quarto of 2(104 at the Refuse Pile, which is located at the Foidel Creek Mine in Routt County, Colorado. During lltis quarter, we visited the project site on February 6, 2004 [o test dte compaction of the waste coal materials being placed and compacted in Area 1; we also visited the project site on March 30, 2004 to provide our quanerly observations. At the time of our site visit on February 6, 2004, we took three (3) compaction tests (#260 to #262) across Area 1 of the refuse pile. All of the tests taken met dte minimum compaction requirement of 90% of the maximwn standard Proctor density. All of the tests taken met the minimum compaction requirement of 90°/a 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 = Maximwn 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 March 30, 2004 we met with Dave Wallace of RAG/Twentymile Coal Company at the pile. It appeared llrat dte contractor was knocking down and leveling the materials that had been stockpiled in Area 2 ''/z. Mr. Wallace stated that they would be ready for compaction testing in this area in the nest several weeks. We also observed [hat they were currently stockpiling the refuse materials in the north and east edges of Area 2. Based on our cursory observations, we did not observe any signs of adverse drainage conditions on the pile or in the haul roads. In fact, the contractor was in the process of cleaning out the surface drainage ditches that are located along the edges of the haul roads at the time of our visit. Based on our limited observations, i1 appears that the pile is currently being consUucted in general accordance with the project specifications. (970) 879.7888 • Fax (970) 879.7891 • nwccl @mindspring.com 2580 Copper Ridge Drive • P.O. Box 775226 • Steamboat Springs, CO 80477