2013-12-05_GENERAL DOCUMENTS - C1981010

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of the Horse Gulch Fill. Based on the current cost estimate it was unclear if spoil material stored in the fill was indeed excess spoil and is not needed for future backfilling and grading work in the K -Pit area. The Division sent TMI a second adequacy review letter dated October 29, 2013 in regards to this issue. On November 12, 2013, Division staff and management met with several representatives of the Trapper Mine to discuss this item as well as other issues related to the cost estimating process. At the meeting TMI clarified this issue and demonstrated that spoil stored within these parcels were not needed for future reclamation efforts at the mine site. Also, based on the Divisions review of these parcels, they have been backfilled and graded in accordance with the approved post mining topography. Trapper Mine responded to the Division's adequacy review with a letter dated November 25, 2013. The response letter summarized the discussion and agreement in regards to this issue based on the November 12, 2013 meeting. Based on the meeting and Trappers response letter, the Division's concern was addressed. III. CRITERIA FOR BOND RELEASE Under Colorado's Permanent Program, the process of releasing the reclamation bond for a mine site is explained in Rule 3.03 and further described in the Division's 1995 Guideline Regarding Selected Coal Mining Bond Release Issues. For Phase I bond release, Rule 3.03.1(2)(a) states, "Up to sixty percent of the applicable bond amount shall be released when the permittee successfully completes backfilling, regrading, and drainage control in accordance with the approved reclamation plan." Evaluation and inspection of the reclaimed areas was based on the specific requirements of the reclamation plan and the functional requirements of the post- mining land use. Criteria for bond release included the following based on the 1995 guidelines noted above: 1. Hillslope and drainage channel gradients and general design compliance; 2. Performance of the reconstructed topography. Symptoms of failure or instabilities such as slumping or exposed highwalls were examined; 3. Hillslope design/function with regard to erosion, 4. Swales and depressions with regard to numbers of features and effect on post- mining land use; 5. Blending of regraded land to undisturbed areas; 6. The functioning of drainages with regard to knickpoints, blending at disturbance boundaries and channel erosion, 7. Erosional features; and 8. Drainage control for the reclaimed area, including upslope diversions. Backfilling of the mined pits is accomplished primarily with draglines. Overburden and inter - burden material from a cut is used to backfill a previous adjacent cut. Other equipment such as bulldozers, scrapers, backhoes, front end loaders and trucks are also used to backfill areas. Once a pit is backfilled bulldozers and /or graders grade the area. With regard to Phase I bond release, the approved reclamation plan for the Trapper Mine calls for backfilling and grading mine excavations and shaping the backfilled areas to the approximate configurations shown on the Postmining Topography Map, Map M12 in the permit. Graded areas are to blend into the surrounding adjacent areas. Every year TMI submits to the Division their Annual Reclamation Report (ARR) and revises Appendix W of the permit. Each ARR includes a map showing actual postmining topography from the previous year. Trapper identifies which parcels had been backfilled and graded that year on the map and the Division reviews reported topography and compares the reported post mine topography to the approved postmining topography. A landside occurred in October of 2006 and Trapper modified their mining and reclamation plan to Trapper Mine Page 6 December 2013 SL -14 Phase I Bond Release