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G. Reclamation of Shop-larehouse Pad: <br />^ The shop-warehouse pad is also within the area designated for potential slide <br />activity. As such, a dewatering system will be installed to stabilize the shop- <br />' warehouse pad during the construction and operational stages of the Mt. Gunnison <br />Mine. <br />' The shop-warehouse pad is different from other building pads in the landslide area <br />in that it has a downslope (fill side) retaining wall, but no upslope (cut side) <br />retaining wall. The recommended reclamation procedures for ensuring a stability <br />Factor of Safety of 1.3 are the same as for the substation pad. The dewatering oft <br />' this area must be continued after all reclamation activities have been completed..r <br />Once all superstructures have been removed, the downslope retaining walls can be; <br />removed and the section can be baekfilled in uniform layers to at least 859K of the)4 <br />maximum Standard Proctor Density. Backfill should continue until the area is <br />returned to its approximate original contours (AOC) <br />' H Reclamation of Portal Bench: <br />The Portal Bench area is also within the area designated for potential slide <br />activity. As such, both a horizontal drain system and a french drain have been <br />designed and will be installed to stabilize the portal bench and upper slope during <br />the construction and operational stages of the mine. <br /> The portal bench is comparable to the situation of the Portal Turnout at Access <br />' Road Station 65+D0. The recommended reclamation procedures for ensuring a <br /> stability Factor of Safety of 1.3 are similar to these recommended for that case. <br /> The dewatering of this area must be continued after all reclamation activities have <br />' been completed. Once the conveyor system,guard rails, and other miscellaneous <br /> bench structures have been removed and salvaged, the section can be baekfilled in <br /> uniform layers to at least 85% of the maximum Standard Proctor Density. The <br /> retsining walls at the Portal Entries should be left in place to increase Iocal <br /> stability in this area. The top segment oP the wall, however, should be removed <br /> below the anticipated topsoil depth. Backfill should continue until the area is <br /> returned to its approximate original contours (AOC). <br /> Therefore, at the Portal Bench the following reclamation procedure is <br />' recommended to ensure a stability Factor of Safety oP 1.3 of more. <br /> 1. inspect the horizontal drain outlets and french drain outlets to ensure that <br /> the dewatering system is operating properly. Check all piezometer levels <br /> and take any necessary measures to protect the piezometer installations. <br /> 2. Carefully remove and dispose of the concrete structures protecting the <br /> outlets of the horizontal drains. <br /> 3. Remove all mine conveyors, guard rails and miscellaneous bench structures. <br />' 4. Remove top portion of the portal retaining wall structures so that the top oY <br /> the wall is below the proposed top soil depth. <br /> 5. Construct a bulkhead Por each entry, providing for drainage through the <br />Backfill zone, if necessary. <br /> 6. Backfill to the approximate original contours (AOC), minus topsoil depth, in <br /> uniform 8" lifts. Backfill to at least 85% of maximum Standard Proctor <br />' Density. <br />10 <br />