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3. Hillslope design/function with regard to erosion; <br />4. Swales and depressions with regard to numbers of features and effect on post- mining land use; <br />5. Blending of regraded land to undisturbed areas; <br />6. The functioning of drainages with regard to knickpoints, blending at disturbance boundaries and <br />channel erosion; <br />7. Erosional features; and <br />8. Drainage control for the reclaimed area, including upslope diversions. <br />Backfilling of the mined pits is accomplished primarily with draglines. Overburden and inter - burden <br />material from a cut is used to backfill a previous adjacent cut. Other equipment such as bulldozers, <br />scrapers, backhoes, frontend loaders and trucks are also used to backfill areas. Once a pit is backfilled <br />bulldozers and /or graders grade the area. With regard to Phase I bond release, the approved reclamation <br />plan for the Trapper Mine calls for backfilling and grading mine excavations and shaping the backfilled <br />areas to the approximate configurations shown on the Postmining Topography Map, Map M12 in the <br />permit. Graded areas are to blend into the surrounding adjacent areas. Every year TMI submits to the <br />Division their Annual Reclamation Report (ARR) and revises Appendix W of the permit. Each ARR <br />includes a map showing actual postmining topography from the previous year. Trapper identifies which <br />parcels had been backfilled and graded that year on the map and the Division reviews reported <br />topography and compares the reported post mine topography to the approved postmining topography. <br />A landside occurred in October of 2006 and Trapper modified their mining and reclamation plan to <br />address stability and safety concerns for mining within the slide area. As a result of the slide, TMI <br />devised a plan to backfill excess spoil from the K -Pit excavations and created a fill area known as the <br />Horse Gulch Fill. Designs for the Horse Gulch fill are located in Appendix T of the permit. Horse Gulch <br />Fill was designed to store 24.6 million BCY of excess spoil. The west face of the fill is not to exceed a <br />3:1 horizontal to vertical ratio slope. Approximately a 30 foot horizontal bench will be constructed every <br />100 vertical feet of the fill. An under drain was to be constructed in accordance with the approved <br />designs located in Appendix T of the permit. <br />IV. OBSERVATIONS AND FINDINGS <br />The bond release inspection was conducted on November 20, 2013. The Division had evaluated the post <br />mine topography on the SL -15 parcels during an inspection conducted on October 24, 2013. Details of <br />the Divisions observation during these inspections can be found in their respective inspection reports. <br />The SL -15 Bond Release Application Maps (Sheets 2 to 3) submitted by TMI depict the bond release <br />area. Also, as a reference for this document; enclosed is Attachment 1, the SL -15 bond Release Areas <br />Map (Sheets I to 3) generated by the Division using the maps submitted with the application. <br />Compliance with Annroved Post Mining Topouauhv <br />The Division evaluated the reclamation parcels to determine if the affected areas have been backfilled <br />and graded in accordance with the approved post mine topography. To evaluate the SL -15 bond <br />release block for Phase 1 bond release, the Division compared the approved post mining topography <br />(PMT) as depicted on Map M12 in the permit to the actual on the ground topography after backfilling <br />and grading had occurred. The SL -15 bond release maps submitted with the application depict the <br />actual on the ground topography after backfilling and grading has occurred. During the field <br />inspections, the Division confirmed the on- the - ground topography of the bond release parcels. <br />Using ArcMap 10, the Division geo- referenced the approved PMT Maps; Map M12 and the SL -15 <br />Trapper Mine Page 6 January 2014 <br />SL -15 Phase I Bond Release <br />