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January 3, 2012 <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 20, 2012, by Tonia M. Perkins, a licensed professional engineer in the State <br />of 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 />At the time of the inspection, the dump was covered with approximately two feet of snow. Both the <br />south west side of the dump and the north east spoil side of the dump were inspected this quarter. No <br />appearances of instability, structural weakness, or other hazardous conditions were observed. The area <br />where a spring was discovered during the third quarter 2011 inspection was inspected. There was no <br />detectible water flow at the time of the inspection. <br />2.0 Critical Construction Periods <br />2.1 Removal of All Organic Material and Topsoil <br />Topsoil and organic material removal activities were not conducted during the quarter. <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. During the time of the inspection, there was no detectible water flow. <br />2.3 Installation of Surface Drainage Systems <br />The uppermost section of the north surface drain was completed during the quarter between the 7550 <br />and 7570 elevations. Both the north and south surface drains were inspected. At the time of <br />inspection there was no water flow in either of these drainages. The areas of the south drain that <br />showed erosion on the third quarter inspection were repaired. A track hoe placed larger rock on the <br />drainage bottom and reconstructed the bottom to slow down the water flow in the ditch. <br />2.4 Placement and Compaction of Fill Materials <br />Fill material was placed during this quarter. The fill material for this quarter was placed by Komatsu <br />830E -AC haul trucks. Dump areas were limited to 50' in height, in accordance with the approved design, <br />though 25' to 35' lifts were the typical dump height for all lifts during the quarter. GPS equipped dozers <br />were used to knock down truck placed spoils, assuring construction consistent with the approved <br />design. <br />The fill placement during this quarter was consistent with the approved design, and prudent <br />construction methods. Photographs 1 and 2 depict the extent of fill placement near the end of the <br />