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<br />6.Radial Stacker Boom <br /> <br />7.System Control Building <br />-built <br />structures can be released from the bond liability. <br />Backfilling and Grading and Site Drainage <br />Backfilling and grading work was conducted in 2011 in the SL-1 bond release area. Exhibit 18-1 of the <br />permit depicts the current approved Post Operational Topography of the SL-1 area. Within Tab 04 in <br />the permit, the Exhibit 4 map depicts the pre-operational topography. The topography on the Exhibit 4 <br />map depicts a gentle hill slope with a southern and eastern aspect for the SL-1 release area. The Exhibit <br />18-1 map provides greater detail of the approved post operational contours. Exhibit A and B maps <br />submitted with the SL-1 application depict the actual topography of the site after backfilling and grading <br />was conducted. Exhibit C and D depict several cross sectional drawings of the SL-1 area. These maps <br />were reviewed and compared to the pre and post operational topography maps. The cross sections <br />provided correspond to the topography depicted on the Exhibit A and B maps. While there are some <br />slight variances, the topography depicted on the Exhibit A and B maps is very similar to the approved <br />post mine operational topography. <br />During the site inspection, the Division field verified the backfilling and grading work completed. In <br />order to accomplish this, two transects were walked within the reclaimed area and elevations points were <br />collected along each transect using a Trimble YUMA GPS unit. A profile of the elevations collected <br />with the GPS unit along each transect was created. Using the Exhibit A Map submitted with the SL-1 <br />application and the Exhibit 18-1, Post-Operational Topography and Vegetation map approved in the <br />permit, the Division was able to create elevation profiles of each point on the transects by interpolating <br />the elevations on the maps. Using these profiles, a comparison was made between the actual backfilled <br />and graded area and the topography approved in the permit. For more detail on the comparison, please <br /> <br />Given the review and field observations, the Division has determined that the Operator has graded the <br />area as depicted on the SL-1 map. The post mine topography varies slightly from the proposed post <br />mine topography depicted on the Exhibit 18-1 Map within the permit, however they are very similar. <br />The area has been graded to match the surrounding topography with a gentle south and east aspect. The <br />reclaimed area is stable, no slumps or slides were observed. <br />Based on the profiles submitted with the application, the slopes were graded from a .1% to a 13.2% <br />slope. The steepest slope was located in the northwest corner of the SL-1 area. No permanent drainage <br />channels were created within the SL-1 area. The reclaimed land provides for positive drainage to the <br />th <br />south and east into Ditch 3a and Ditch 3 which drain into the Rail Loop Pond. During the June 5, 2012 <br />inspection it appeared a portion of Ditch 3 paralleling the south side of the rail line was not draining as it <br />was designed and was pooling in the middle of the slope of the drainage. After the inspection the ditch <br />was repaired. Susan Burgmaier with the Division conducted a follow-up inspection on June 25, 2012 <br />and verified the Ditch 3 had been repaired and should function as it was designed. The drainage <br />control system is in compliance with the approved plan. <br />7 <br />