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Mine #3 <br />The existing sediment pond shown on the mine map is in an area <br />where fill must be obtained, therefore it must be removed. Since <br />the flat area below the backfilled slope is in competent rock, <br />furrows placed in this area will not threaten slope stability and <br />they will trap moisture helpful to revegetation and at the same <br />time lessen sediment erosion as the pond did during mine operation. <br />No furrows will be placed on the fill slope at 2.0:1.OV. This <br />practice of furrowing has been successfully used in lieu of <br />sediment ponds at other coal mines as an experimental practice. It <br />is well suited to this site. The furrows will be approximately 1.0 <br />feet to 2.0 feet deep. <br />The immediate area above the two spoil outslopes will slope away <br />from the outslope and direct all runoff into a furrow /ditch <br />draining away from the fill as shown on the map titled - Mine #3 <br />Reclaimed. <br />A rock filter berm will be placed at the bottom of the North Fill <br />as a best available technology to trap sediment from the spoil <br />slope. <br />Mine #4 <br />The Mine #4 portal area consists of two distinct benches and fill <br />slopes as shown on the enclosed map titled - Mine #4. The Upper <br />Bench is the largest and has the greater fill slope. <br />A sediment pond trapping runoff from the disturbed area is located <br />immediately west of the upper bench. A catchment basin also exists <br />at the bottom of the spoil slope. It is proposed that furrows <br />similar to that described above be used at Mine #4. These furrows <br />are shown on the map titled - Mine #4 Reclaimed. Using <br />furrow /ditches at the top of the two spoil slopes, runoff will be <br />directed away from the spoil slope as shown. Again, the furrows <br />trap water helpful for revegetation while at the same time, reduce <br />erosion and gullying. No furrows will be placed on the backfilled <br />slope at 2.OH:1.OV. <br />A rock f i l t e r berm w i l l be placed at the bottom of the main fill as <br />a best available technology to trap sediment from the spoil slope. <br />The existing small sediment pond immediately west of the Upper <br />Bench should remain since it is stable and will be useful for the <br />post- mining land uses of wildlife habitat and grazing. <br />