2010-06-14_REVISION - C1994082 - Laserfiche WebLink

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properly reclaimed with the exception of a short reach at the lower (northwest) end, which has been approved as Light Use Road LU-2. Channels PM-10, PM-21, PM-21A, and PM-21B were observed to be stable and in conformance with approved designs. One gully that will require maintenance extended up-slope and to the south from the upper end of PM-10. The gully is considered a maintenance item to be stabilized by the operator in accordance with the Rill and Gully Plan of the approved permit. All of the exclusion areas under SL-1 will be proposed for Phase I bond release approval under SL-2, with exception of the entire length of Channel PM-13 as described below. In the Grassy Creek watershed portion of the North Pit area, heavy rains earlier in the year had resulted in significant erosion along PM-13, and slope areas that drain into both PM-13 and PM-9. Detailed observations are included in the Division's follow-up bond release inspection conducted on 10/13/09. Erosion repairs had been implemented in the watershed prior to the 10/13 inspection, but were not yet complete. Gullies had been graded out and fully repaired in some locations. Minor riprap repairs were warranted along the upper section of PM-13, where underliner material had been exposed. Given the continued erosional instability of the watershed, including areas tributary to Channel PM-13, and the maintenance warranted along the upper end of PM-13, the Division will exclude the entire length of PM-13 from SL-2 approval. The excluded corridor along PM-13 is 1.8 acres and is delineated on Figure 3a - Phase I Bond Release Proposed Approval Areas. Figures 3a and 3b show the SL-2 Phase I proposed approval and exclusion areas for the north and south portions of the mine site, respectively. Photograph No. 2 shows the erosion that is occurring at the head of the PM-13 channel. Although the Division noted in the October 2009 inspection report that exclusion of Channel PM-9 from SL-2 approval might be warranted, it was subsequently determined that Phase 1 release had been granted for PM-9 in SL-1. Although there was heavy runoff and resultant erosion in the PM-9 watershed during 2009, the channel itself remained stable. South Pit Area The largest acreage requested for release within SL-2 is in the South Pit area. For the purposes of SL- 2, the South Pit area includes all disturbed lands located to the south of the Section 18/19 and Section 17/20 boundary lines, within the permit area. Reclaimed watersheds within the South Pit area drain to one of three sedimentation ponds; Pond 012, Pond 013, or Pond 014. The Pond 012 watershed is the largest, Pond 013 watershed is the smallest. Each of the major pond watersheds contains several sub-watersheds, with their associated permanent channel network. Backfill and grading, in the South Pit Area was initiated in 2000 and was completed in 2007 for all areas included in the SL-2 Phase I bond release. Exhibit B of the bond release application package provides detailed information on the chronology of Backfill and grading work in the South Pit. There was no backfill and grading work completed in 2001 or 2002 and the majority was completed in 2005 through 2006. Photograph No.'s 3 and 4 show views of the South Pit from the southeast end of the disturbance area looking north before and after reclamation, respectively. Photograph No. 3 was taken in 2005 during active mining. Photograph No. 4 shows the South Pit area following backfill and grading, drainage reestablishment, and revegetation and demonstrates that the site was returned to the approximate original contour. Areas not included in the release request include all sediment ponds and stock tanks, permanent roads, certain light use roads in the South Pit and Neck Pit vicinity 11