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oiora Geotechnical /Environmental Engineering • Materials Testing ~~/~u/ ~~~ r,<- ~~ i, ~w ~~ u September 14, 2004 Twentymile Coal Company 29515 RCR #27 Oak Creek, CO 80467 Atm; Mr. Jerry Nettleton Job Number: 99-3983 RECEi\/ED SEP 2 2 2004 -'-^_'-'~-_"~, -- ~--`~ '- - - - --~-'~Divisionof-Minerals and Geology-- Subject: Quarterly Observation Report, Refuse Pile, Foidel Creek Mine, Routt County, Colorado. Mr. Nettleton, As requested, NWCC, Inc. has prepazed this report outlining our observations made during the second quartet of 2004 at the Refuse Pile, which is located at Twenrymile Coal Company's (TCC) Foidel Creek Mine in Routt County, Colorado. Dttring this quarter, we visited the project site on May 19 and 26, and June 15, 2004 to test the compaction of the waste coal materials being placed and compacted in Areas 1, 2 and 2'/s. We also visited the project site on June 29, 2004 to provide our quarterly inspection/observations. At the time of our site visit on May 19, 2004, we took eight (8) compaction tests (#263 to #270) across Areas 2 and 2'/ of the refuse pile. All but two of the tests taken (#263 & #269) met the minimum compaction requirement of 90% of the maxdmum standard Proctor density. Dave Wallace of TCC was advised of the areas in which the failing tests were recorded. We revisited the site on May 26, 2004 and took retests in the areas in which the failing tests were recorded on May 19, 2004. These aeeas had been reworked and recompacted and the two retests (#263A and #269A) met the required compaction specification of 90% of the maximum standard Proctor density. We visited the site a third time on June 15, 2004 and took compaction tests on the fill materials placed in Areas 1 and 2'/,. We took seven (7) compaction tests (#271 to #277) on this date. All of the tests taken on this date met the minimum cmnpaction 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 abbret~ations given in the Nuclear Density Test Results (Proctor Data) are as follows: Maximum DD =Maximum Dry Density and OMC = Optimum Moistwe Content. Both of these values have been determined in accordance with ASTM D698/AASH'I'O T99. At the time of our site visit on June 29, 2004 we met with 3erry Nettleton and Sandra White of RAG/Twenrymile Coal Company at their office. We. also conducted a site inspection on this date. Based on our observations made during this visit, it appeazed that the contractor was pushing the previously stockpiled materials in Area 3 to Area 2 % and then compacting them with the dozer. We also observed that they were currently stockpiling the refuse materials in Areas 1 and 2. (970) 879.7888 • Fax (970) 879.7891 2580 Copper Ridge Drive • P.O. Box 775226 • Steamboat Springs, CO 80477