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<br />HIGHWAY SLOPE: This is a pre-permit feature that has not been affected since <br />the permit was issued. <br />SEDIMENT BASIN: The sediment basin located in the northwest corner of the pit <br />is the first step in the 10 to 15 year process of backfilling approximately <br />1/3 to 1/2 of the original excavation (about 3.5 million cubic yards <br />extracted) with waste from the operation to the south. In the future other <br />basins will be established adjacent to and eventually on top of this basin to <br />accomplish the backfilling process as approved in the 1985 amendment. If <br />reclaimed at present, Hoch of this sediment basin would be covered through <br />backfilling and slope reduction on the north and west sides of the basin. <br />WEST AND NORTHWEST STEEP SLOPES: Under the permitted plan these slopes would <br />have a 3:1 gradient. After filling much of the pit with sediment basins the <br />slopes would be rather low and short. At present producing a 3:1 slope would <br />require a cut and fill operation and would produce long slopes that could be <br />subject to erosional damage due to their length. Fill to the north of the <br />sediment basin (labeled "BACKFILL") could be used to help create the final <br />slopes. <br />TOPSOIL STOCKPILE: (Volume = 1,500 yd3) This stockpile would best be used to <br />cover the south facing slopes created on the north end of the pit. Those are <br />the most difficult to revegetate and would benefit the most from the limited <br />soil resource available. If any soil was left it would best be used on the <br />east facing slopes on the west side of the pit. <br />PIT BOTTOM: In the current permit the present pit bottom would be under up to <br />about 50 feet of fill. If reclamation needed to be done today the pit bottom <br />would need to be ripped to remove the compaction and then seeded. No soil <br />would be available, but the use of deep rooted legumes would produce goad <br />success without soil as much of the pit bottom is only a few feet above <br />groundwater. This would provide a subirrigation effect and would eventually <br />even be invaded by cottonwood trees as has occurred in the past in areas where <br />disturbance has not occurred for a few years. <br />PILES: (Total volume = 3,000 yd3) The piles immediately east of the sediment <br />basin are currently stored there for recycling purposes. One pile is <br />primarily concrete waste while the other is asphalt. It is expected that <br />these will be crushed in the near future, but if reclamation was to be done <br />today these piles could provide some course backfill material to provide <br />additional strength to slopes. <br />SUMMARY: If reclamation was implemented today, the work in this pit would <br />primarily involve slope reduction through cut and fill to produce about 3:1 <br />slopes on the north and west sides of the pit. The bottom of the pit would be <br />ripped and seeded with deeply rooted species. The north access road might be <br />removed, but it might also be left if adjacent landowners desired it be left <br />for their use. Erosion control not called for in the current plan would <br />probably be needed on most slopes because the slopes would be much longer than <br />the permitted plan calls for. <br />Total area needing topsoil, as available, and revegetation = 31.3 acres. <br />Page 3 Bonding Information M-73-007/M-77-213 January 7, 1992 <br />