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4. Swales and depressions with regard to numbers of features and effect on post -mining land <br />use; <br />5. Blending of regraded land to undisturbed areas; <br />6. The functioning of drainages with regard to knickpoints, blending at disturbance boundaries <br />and channel erosion; <br />7. Erosional features; and <br />8. Drainage control for the reclaimed area, including upslope diversions. <br />Colowyo's approved reclamation plan was prepared in accordance with Rule 2.05.4. Colowyo was <br />granted a variance for contemporaneous reclamation for the East Pit, West Pit and the South <br />Taylor Pit due to the nature of multi -seam mining. Backfilling and rough grading commenced <br />once a steady-state condition was reached in each of the pits. <br />The approved backfilling and grading plan for the Colowyo Mine is found in Volume 1 (East and <br />West Pit), Volume 12 (South Taylor), and Volume 15 (Collom) of the PAP. Maps 19, 19A and <br />19B show the approved post -mining topography, Maps 29 and 29A, and 29B show the <br />backfilling and grading schedule, and Maps 41, 41A, and 41B show the location of the <br />permanent, post -mining drainage channels. The pre -mining and post -mining cross-sections are <br />shown on Maps 20, 20A and 20B, and the permanent drainage channel profiles are shown on <br />Maps 33, 33A, 33B, and 33C. Map 3 of the SL -13 application show cross-sections of the SL -13 <br />area, including approved post mining topography alongside the constructed topography. <br />IV. OBSERVATIONS AND FINDINGS <br />The following discussion of observations and findings focuses on the results of backfilling and <br />grading work and drainage reestablishment in the West Pit, East Pit, Old Administration Building <br />area, and the Collom ancillary expansion areas for the SL -13 partial Phase I Bond Release. <br />The evaluation of the bond release application included the bond release inspection, an office <br />review of the permit requirements and regulatory criteria, and review of past inspection reports. <br />The bond release inspection was conducted on May 23, 2018. Several items were reviewed by the <br />Division during the technical evaluation of the bond release application before, during, and after <br />the inspection, including: the post -mining topography and cross-sections of backfilled and graded <br />areas. <br />During the partial Phase I Bond Release inspection, participants walked through most of the <br />bond release request area to allow for visual assessment of compliance with pertinent <br />requirements. <br />Backfilling and Grading <br />For SL -13, observations were made during the bond release inspection with regard to <br />approximate original contour and stability of the reclaimed landscape. To determine compliance <br />with Colowyo's approved approximate original contour (AOC) in the SL -13 areas, elevation data <br />Proposed Decision and Findings of Compliance August 30, 2018 <br />Partial Phase I Bond Release SL -13 Page 5 <br />