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December 19, 2013 <br />1.0 Introduction <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 19, 2013, 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 />No appearances of instability, structural weakness, or other hazardous conditions were observed. Both <br />the south west side of the dump and the north east spoil side of the dump were inspected this quarter. <br />The area where cracks were detected on the top south portion of the dump during the first quarter <br />inspection was inspected. There was no additional cracking found. During the second quarter <br />inspection, there were two spots above the 7350' elevation on the south side of the dump that showed <br />some differential settling. Both areas appear to have settled a bit more. There weren't any signs of <br />bulging at the toe or any cracking. These areas will be monitored on a regular basis. The area where a <br />spring was discovered during the third quarter 2011 inspection was inspected. There was no sign of <br />flowing water. <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 approximately half a gallon per minute of <br />water flow. <br />2.3 Installation of Surface Drainage Systems <br />Both the north and south surface drains were inspected (photographs 1 and 2). At the time of <br />inspection there was no water flow. The north drain was extended to the top of the 3:1 slope area and <br />was completed this quarter (photograph 3). The top ditch on the north end was extended to the <br />completed north drain (photograph 4). On the south end of the fill the bench and the top ditch were <br />maintained during this quarter as well (photograph 5). <br />2 <br />