2008-05-01_REVISION - M1973007SG (5)

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MINING PLAN would come out from under the highway and the re-connection with the current ditch will likely be less than one foot over a distance of about a mile. Initially, the elevation of the surface where the ditch will be installed should be equal to the depth of the ditch plus one or two feet. Thus,when the ditch is actually installed careful surveying can determine exactly how much additional material needs to be stripped off the surface to produce just the right elevation so the ditch will have a smooth flow line. Although initially removing a bit more sand than should be removed would not compromise the integrity of the ditch, having to replace material to elevate the ditch corridor could introduce small differences in the support material that could cause cracking of the concrete if there is insufficient compaction of any fill. Therefore, mining sand along the actual ditch corridor to a depth of final ditch elevation plus ditch depth plus one to two feet is advisable. By the time the ditch is ready to be installed, much of the revegetation above the ditch on the highway slope and the upper portions of the slope on the east side of the North Mining Area should be either completed or well along toward completion. Although revegetation after installation of the ditch would be possible, revegetation before installation will reduce the difficulties with sedimentation into the new ditch channel. Furthermore, topsoiling and planting above the ditch after the ditch has been installed presents its own problems with sedimentation. The upper edge of the highway slope must be carefully located so as to not excavate too far to the north which could influence the construction of the highway. Although there is some flexibility on exactly where the boundary between the pit slope and the highway construction edge is located, that zone is no more than a few feet wide. Not excavating far enough toward the highway would be advantageous to the highway,but could result in significant net loss of sand in the mining and produce a steeper slope above the ditch. Mining too far could force the highway to be partially constructed on backfill which would increase the cost of the highway. Therefore, the precise line for the boundary between the pit slope and the highway should be fully established and well defined on the ground well before completing the mining of the pit slope. It is clear from these descriptions, that careful design and coordination must be implemented during the construction of the ditch corridor and highway slope from the land just east of Academy to the eastern edge of the North Mining Area. Other than having the slope above the ditch in native material and the actual ditch route at the proper elevation, extraction of the southward directed leg of the ditch route need not be done with such extreme control as that used along the highway. But still the permit boundary plus any'setbacks (a minimum setback from the permit boundary of 2�`5_ feet w� ill be used) should be carefully observed during mining in this stretch of the ditch corridor. For recT`amation requirements of the slopes,please refer to Exhibit E -Reclamation Plan. Daniels Sand Pit Amendment (2008) Exhibit D Page 23 of 28