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December 22, 2010 <br />1.0 Introduction <br />2 <br />In compliance with Rule 4.09.1 (11) of the Regulations of the Colorado Mined Land Reclamation Board <br />for Coal Mining, a quarterly inspection and report on the construction and associated activities of the <br />Horse Gulch Fill (HGF) at Trapper Mine in Craig, Colorado has been completed. The quarterly inspection <br />was conducted on December 22, 2010, by Seth A. Puls, a licensed professional engineer in the State of <br />Colorado. <br />Construction activity related to the fill has been consistent with the approved design. Details of this <br />design can be found in Agapito Associates, Inc.'s (AAI) Horse Gulch Fill Stability Analysis, dated May 29, <br />2009. <br />No appearances of instability, structural weakness, or other hazardous conditions were observed. <br />2.0 Critical Construction Periods <br />2.1 Removal of All Organic Material and Topsoil <br />Topsoil and organic material removal activities were conducted during fourth quarter of 2010. Topsoil <br />removal occurred from the K1-08 topsoil pile. This material was taken to a new stockpile location, and <br />staged for replacement on reclaimed portions of the fill to occur next summer. All topsoil and organic <br />material is removed prior to placement of fill materials. <br />2.2 Placement of Underdrainage Systems <br />The underdrainge system was completed in the first quarter of 2010; additional work on this system is <br />not anticipated. <br />2.3 Installation of Surface Drainage Systems <br />Initial backfilling of the North and South rip-rap channels with rip-rap occurred during the fourth quarter <br />of 2010. Construction of these channels was not completed during this quarter. Triangular ditches are <br />designed for each of the benches along the face of the fill. Rough grading for these ditches was <br />completed during the quarter, though final grading of these channels was not completed during this <br />quarter. <br />2.4 Placement and Compaction of Fill Materials <br />Fill material was placed during this quarter. Fill was placed along the Northern edge of the HGF by <br />dozers and the Molly Brown dragline. This portion of the fill was inspected for stability, and no <br />appearances of instability, structural weakness, or other hazardous conditions were observed. <br />The bulk of fill material for this quarter was placed by Komatsu 830E-AC haul trucks. Dump areas were <br />limited to 50' in height, in accordance with the approved design, though 30' - 35' lifts were the typical <br />dump height for all lifts during the quarter. GPS equipped dozers were used to knock down truck placed <br />spoils, assuring construction consistent with the approved design.