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1. Hillslope and drainage channel gradients and general design compliance; <br />2. Performance of the reconstructed topography. Symptoms of failure or instabilities such as <br />slumping or exposed highwalls were examined; <br />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 <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 />SCC's approved reclamation plan was prepared in accordance with Rule 2.05.4. The plan for the <br />Seneca II-W Mine called for rough backfilling and grading to be completed within 180 days <br />following coal removal and not more than four spoil ridges behind the active pit. Some delays in <br />contemporaneous reclamation were approved during the course of mining. <br />The approved backfilling and grading plan for the Seneca II-W Mine is found in Volume 13, Tab <br />20 of the permit application package. Exhibit 20-2 shows the approved Post-mining topography <br />and Drainage Map. Pre-and Post-mining Cross-Sections are in Tab 20, Exhibit 20-4. Post Mining <br />Channel Profiles are in Exhibit 20-5. There were no variances from approximate original contour <br />(AOC) requirements or highwall reclamation requested or allowed in the permit area. Exhibit B of <br />the SL-3 application shows the constructed post-mining topography and drainages and depicts <br />cross-section locations; Exhibit C, Post Mine Cross-Section, provides representative cross-sections <br />showing final topography configuration and provides a comparison between the pre and post- <br />mining topography; and Exhibit D shows as-built drainage profiles. <br />As approved in the permit, final interior spoil grading was designed to produce a diverse topography <br />with slopes constructed at as shallow a grade as the conditions would allow. Final highwalls were <br />generally reduced to slopes of 3H: IV or flatter. In some cases backfill material was placed against <br />undisturbed virgin ground at the top of a final highwall where the final slopes may exceed 3H: IV. <br />As indicated in Tab 20 of the permit, slopes could exceed 3(h):1(v) in isolated areas above the final <br />highwall where the natural slope was originally steeper than 3(h):1(v). A sensitivity analysis was <br />run to determine the factor of safety for the backfill by varying the input factors for saturation, pit <br />slope heights and final surface slopes. The stability report and data are included in Attachment 20A <br />of the permit application package. Based on the results of the stability report, all slopes were <br />designed to achieve a static factor of safety of at least 1.3. <br />Included in the post-mine regrading operation was the construction of small swales and hummocks <br />to minimize erosion and to conserve soil moisture and to promote revegetation. These features were <br />constructed on steeper slopes in the reclaimed area. <br />SCC generated topographic maps, using photogrammetric methods, of backfilled and regraded areas <br />on an annual basis. These maps were submitted to the Division each year in the Annual <br />Page 8 of 22