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height in some locations. The operator again regraded the slump location to eliminate the scarp, <br />cracks, and bulging, and to improve drainage along the road ditch along the toe of the slump <br />subsequent to SL-2 inspection, in the late fall of 2009. Due to the condition of the slope at the time <br />of the SL-2 inspection, and given the history of instability and uncertainty regarding the effectiveness <br />of the most recent repair, the Division is excluding the "A" Pit highwall slope failure area <br />(approximately 9.8 acres) from the SL-2 proposed approval area. <br />An area where regrading did not achieve proper blending is at the boundary between the regraded <br />area and the undisturbed hillslope, which was observed the March 24, 2010 inspection. The area had <br />not been noted during the SL-2 inspection in October 2009. The feature of concern is at the crest of <br />the reclaimed slope due north of the location where the Oil Well Access road crosses Channel 006- <br />NE1. There is a remnant scraper route along the crest of the graded, topsoiled slope. The reclaimed <br />slope was originally disturbed to construct a temporary overburden stockpile, which was never <br />constructed. The scraper route along the crest of the slope was not properly eliminated and reclaimed <br />following topsoiling of the slope. The scraper route runs along the upper disturbance boundary for <br />approximately 500-600', in a location where the disturbance boundary corners sharply from NNE to <br />due East, and is not readily visible from lower portions of the slope. There is a steep cut slope <br />associated with the feature, which is at least 12' high in some locations and lacks vegetative cover <br />along most of its length. Grading will be necessary to eliminate the route and associated cut slope, <br />and to blend the reclaimed slope in to the undisturbed slope above. A 12.1 acre area that is large <br />enough to provide for access to the location and allow for completion of the project is excluded from <br />the SL-2 Phase 1 Bond Release proposed decision. Elimination of the scraper route segment and <br />associated cut slope is to be completed in 2010. <br />Drainage Reestablishment <br />All permanent post-mine drainage channels were evaluated and inspected as part of this Phase I bond <br />release to assess general design compliance. To the extent possible, drainage channels were <br />reestablished to their original natural pattern to minimize erosion, to conserve soil moisture, and promote <br />vegetation. Reconstructed drainages blend well with off- site drainage patterns and the drainage density <br />is appropriate and similar to adjacent undisturbed areas. Approved permanent drainages in the original <br />permit area are depicted on Figure 2of this document, Exhibit B of the SL-2 Application "Postmine <br />Topography and Drainage", Permit Exhibit 20-2 "Postmining Topography and Drainage Map", and <br />listed in the Permit Attachment 20-1-1 "Postmine Channel Design Summary". Comparison of the <br />Post-mining Topography Map (Exhibit 20-2) to pre-mining topography as depicted on permit Exhibit <br />7-6 "Drainage Basins" indicates that most pre-mining drainages were constructed in their <br />approximate original locations. A comparison of Exhibit 20-2 from the permit with Exhibit B of the <br />SL-2 application indicates that post-mine drainages were constructed in the appropriate locations <br />with adequate drainage density. <br />In the original permit area, the post mine drainages include 005 Gulch and its main tributary 005-El; <br />and 006 Gulch and its tributaries 006-NE1, 006-NE2, 006-E1, and 006-SEL Several other designed <br />permanent tributary drainages were approved through revisions to the permit, including 005-W1, <br />006-S1, 006-NE3, and 006-NE4. Additional drainage density was added to the post-mining <br />landscape by constructing additional post-mine channels that were "field fit" in accordance with <br />12