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5 <br />variances from AOC and no variances from highwall reclamation had been granted by the Division. <br />Comparison of the pre-mine topography map with the approved post-mining topography map shows <br />that the approved plan for reconstructing the mined land approximates the general aspect, drainage <br />patterns and drainage gradients of the original pre-mining land. And comparison of the approved posE <br />mining topography map with the as-built topography map shows that the as-built topography <br />approximates the approved topography design. There also was a generally favorable comparison of <br />the approved post-mining and the as-built topographies on the cross-sections and profiles that had been <br />supplied in the bond release package. There were several apparent minor differences in [he local <br />gradients and local elevations between the approved and as-built topographies as displayed on the <br />cross-sections and profiles. According to [he operator, some of these differences were a result of the <br />mapping methodology, not the actual elevation points. Regardless, [he cross-sections and profiles of <br />the regraded slopes show a stable configuration. There is a commitment, on page 3-42 of Volume 3 <br />of the permit application, that regraded slopes will not exceed 3h:ly, except that where the original <br />ground was steeper, the regraded slopes can be up to 2.25h:1v. Examination of the cross-sections and <br />profiles at representative locations shows [hat this commitment was fulfilled. <br />The second [Weans by which the success of the backfilling and grading and drainage reestablishment <br />was determined was through the bond release field inspection. This inspection was conducted on <br />November 4 through November 6, 1996. Present were representatives of the Colorado Division of <br />Minerals and Geology, Trapper, the Office of Surface Mining and the Bureau of Land Management. <br />During this field inspection, an evaluation was made as to the overall compliance with the approved <br />backfilling and grading plan, including cross-section and profile gradients, the success of the <br />reconstructed landscape in achieving slope stability and in covering all highwalls, the effectiveness <br />of the regraded topography in con[rollingerosionon the regraded slopes and in the rebuilt drainages, <br />the blending of the regraded landscape with the surrounding countryside, and the proper functioning <br />of [he drainage and sedimentation control system. <br />The field inspection showed that the as-built backfilling and grading complied with the approved <br />reclamation plan. None of the lands submitted for Phase One bond release showed any signs of <br />structural instability. Slope gradients were mild and no evidence of slumping was observed. There <br />were several settling cracks observed in the flat, northern section of the West Buzzard drainage. <br />However, they did not appear to be associated with any mass movement of backfilled material. No <br />highwall remnants were visible on any of the reclaimed land. Most of the reclaimed slopes and <br />drainage showed no signs of erosion. There was some erosional gullying in the No Name drainage but <br />these occurrences were of a local nature only and did not appear to represent the area in general. <br />The general character of the reclaimed slopes and reconstructeddrainagewayscomparedfavorably with <br />the surrounding terrain. Post-mine drainage patterns generally had been fashioned after the pre-mine <br />drainage patterns. The reclaimed land topographically blended well with the surrourcling, undisturbed <br />terrain. Where there had been a minor divergence from the original drainage flow, such as in the West <br />Buzzard side drainage, the somewhat increased drainage density would appear to enhance wildlife use <br />