Laserfiche WebLink
July 6, 2011 2 <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 June 30, 2011, by Tonia M. Perkins, 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 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. <br />2.3 Installation of Surface Drainage Systems <br />Surface drainage systems were not installed during the quarter. <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 30' - 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. Photograph 1 depicts the extent of fill placement near the end of the quarter. <br />As fill material is placed above a previous dump level, the surface of the previous dump is ripped with a <br />D -10 dozer to prevent the formation of perched water tables. Large snow accumulations are cleared <br />prior to being dumped over. <br />At the end of the second quarter of 2011, the active dump is at the 7600' and 7625' levels. Rough <br />grading work, sloping the face of levels to the designed 3H:1V slope is currently being done from the <br />7600' down to the 7470' bench of the fill. <br />