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Colowyo C-1981-019 16 Sept 2009 Pg 3/5 e?�7 Backfilling and Grading (cont): - As noted in previous reports, there is a fairly large area in the older (2007-2008 vintage) reclamation that has developed a problem with rills and gullies. The general rill and gully area was walked with a GPS and was approximately 40 acres. It runs from bottom of the Prospect drainage area to the south edge of the 2007-2008 reclamation to the light-use road along the power lines to the light-use road on the north side of the reclamation block (see the attached map/picture for a detailed location). The gullying in this area is quite extensive and remedial measures will need to be taken to ensure the long-term stability of this area. Several of these gullies have breached the contour ditches cut into the reclamation. Although these ditches have been fixed, if the gullies are not repaired they will breach again and the gullies will get worse. In addition to the gullies, there were several large cracks noted in the reclamation in this area. Colowyo should survey this area for rills and gullies and cracks in the backfill and repair or monitor as necessary. *Please see the picture/map at the end of this report* Topsoil: - Colowyo has replaced topsoil to the entire 2009 reclamation block in the East Pit. The topsoil was brought to the area using haul trucks and spread with dozers. The replaced topsoil was tracked with a dozer to roughen the surface slightly but addition roughening, such as ripping, chisel plowing or discing, would be beneficial. Colowyo has cut contour ditches into the small area north of the Prospect Ditch and has indicated that contour ditches would be cut into the remaining area once the seeding is completed (in early October). The Division dug seven test holes to verify the topsoil depth in the 2009 reclamation block. The following chart shows the locations of the holes and the topsoil depths. Currently, the average topsoil replacement depth for topsoil is 8 inches. Based on the seven test holes, Colowyo has replaced an average of 9 inches of topsoil in this portion of the East Pit. *Please see the picture/map at the end of this report for topsoil test hole locations* Depth Location tasting Northing in. EP-TS1- 12" 261005.382 4457264.997 12 EP-TS2-7" 260982.020 4457152.213 7 EP-TS3-8" 261090.482 4457215.560 8 EP-TS4-9" 261216.867 4457366.787 9 EP-TS5-6" 261320.198 4457460.462 6 EP-TS6- 11" 261356.330 4457598.869 11 EP-TS7- 10" 261083.824 4457377.842 10 Average Depth 9