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III. APPROVAL CRITERIA FOR BOND RELEASE <br />Phase I Bond Release <br />Rule 3.03.1(2)(a) states: <br />"Up to sixty percent of the applicable bond amount shall be released when the permittee <br />successfully completes backfilling, regrading, and drainage control in accordance with the <br />approved reclamation plan." <br />Trapper Mine accomplishes backfilling of the mined pits primarily with draglines, using overburden <br />and inter -burden material from a cut to backfill a previous, adjacent cut. Other equipment such as <br />bulldozers, scrapers, backhoes, front-end loaders and trucks are also used to backfill areas. Once <br />backfilled, bulldozers and/or graders grade the area to achieve approximate original contour. The <br />approved reclamation plan for the Trapper Mine calls for backfilling and grading mine excavations and <br />shaping the backfilled areas to the approximate configurations shown on the Postmining Topography <br />Map, Map M12 in the permit. Graded areas are to blend into the surrounding adjacent areas. Every <br />year TMI submits to the Division their Annual Reclamation Report (ARR) revising Appendix W of the <br />permit. Each ARR includes a map showing actual post -mining topography from the previous year. <br />Topographic cross sections, drainage profiles comparing as built and approved drainage profiles will <br />be the same as those given in the permit. All reestablished drainages are delineated on Map 1. TMI <br />has spared no effort and expense in constructing reestablished drainages effectively controlling erosion <br />and downstream sediment deposition. Various sediment control materials and methods and sediment <br />reducing measures have been implemented on reestablished drainages. Drainages at Trapper Mine are <br />trapezoidal in shape with a bottom width of 20 feet, grass lined with regularly spaced check dams. <br />Rock check structures dissipate the energy of flowing water within channels. Debris and sediment <br />deposition occurs upstream of structures allowing vegetation to establish behind structures, further <br />stabilizing the channels. This configuration results in shallow flow depths for the design storm and <br />low flow velocities. Rock Channel slopes are generally 10 percent. Detailed engineering criteria <br />regarding drainage reconstruction practices can be found in TMI's permit Appendix Q Section <br />XXXVII. <br />All lands requested in the current Phase III bond release application, SL20, received Phase I bond <br />release as per Table 2 above. <br />Phase II Bond Release <br />Rule 3.03.1(2)(b) states: <br />"Up to eighty-five percent of the applicable bond amount shall be released upon the establishment <br />of vegetation supporting the approved post -mining land use and meeting the approved success <br />standard for cover based on statistically valid data collected during a single year of the liability <br />period." <br />And, regarding Phase 11 bond release, Rule 3.03.1(3)(b) states: <br />"No more than (60) percent of the bond shall be released so long as the lands to which the release <br />would be applicable are contributing suspended solids to streamflow or runoff outside the permit <br />area in excess of pre -mining levels as determined by baseline data or in excess of levels determined <br />Permit Number C1981010 <br />SL20 Page 6 of 17 <br />