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• Grading to establish access and flat areas for construction of the Washplant, thickener, intermediate feed point, <br />and clean and stoker coal stockpiles on the north side of the overland conveyor <br />• Grading to expand the existing coal stockpile area to the north <br />The regraded configuration and facility locations are shown on Map 24. Required grading involved movement of <br />approximately 54,000 CY of material, with approximately 31,000 CY of cut and 23,000 CY of fill. Supplemental fill <br />material was obtained from the area of the ventilation borehole. Approximately 600 CY of fill was hauled in to the <br />washplant site on the north side of the Overland Conveyor. Approximately 4,000 CY was hauled in from the <br />borrow area to the reclaim tunnel site on the south side of the Overland Conveyor. The borrow area is located in a <br />disturbed area immediately south of the Low - Quality Coal Stockpile. This material was scheduled to be graded <br />downhill during final reclamation of the mine. A berm was constructed on the south end of the proposed coal <br />stoker pad when construction of the preparation plant and bent foundation work was completed, to direct drainage <br />from this site to Pond E. Site preparation and grading activities for the Washplant and coal stockpile expansion <br />required modification of drainage structures in the effected areas. Required modifications, as shown on Map 24, <br />included the following: <br />• Elimination of the lower portion of Ditch D -2 and diversion of the upper portion of Ditch D -2 to Ditch E -2 <br />• Modification of the discharges from Site 109 and the Wedge sump to divert discharge flows to Site 114 <br />(Emerald Springs) <br />• Addition of Ditch E -3 to intercept and route runoff from the former stoker coal storage small area <br />exemption to Pond E <br />• Relocation and reconstruction of Pond E and the resulting relocation of the lower portion of Ditch E -1 <br />consistent with the new pond location <br />• Installation of a new culvert in Ditch D -3 to allow backfilling of a portion of the existing ditch in order to <br />provide both access and a flat area for installation of feed hoppers and transfer conveyors for the proposed <br />preparation plant <br />• Redesign and relocation of a portion of Ditch E -1 on the north edge of the expanded coal stockpile area and <br />associated access road. <br />• Relocation of the culvert which passes flows from Ditch E -2 under the haulroad to Pond E <br />• Construction of a berm along the north and west sides of the clean coal and stoker coal stockpile area to <br />intercept and divert surface runoff to Pond E <br />Design calculations for construction or modification of the noted drainage structures are included in Exhibit 8. The <br />design for Sedimentation Pond E can be found in Exhibit 8E. Also, Plate 1 from Exhibit 13 of Permit C -81 -071 is <br />included within the Pond E exhibit. The design on this plate is followed, except where modified, by the work <br />prepared by Terra - Matrix. <br />In order to facilitate construction of the Washplant it was necessary to drive a total of 84 pilings to support the <br />various Washplant facility buildings. A total of thirty pilings, approximately 10 inches wide and 21 feet in length, <br />were placed under the footprint of the Washplant building. The Thickener building required 20 pilings, <br />approximately 8 inches wide and 24 feet in length. The conveyor supports required 24 pilings, approximately 8 <br />inches wide and 21 feet in length. The reclaim hopper and tunnel required 10 pilings, approximately 10 inches <br />wide and 10 feet in length. A pile - driver was used to install the pilings. Concrete piers were poured around the top <br />of the pilings, requiring a total of approximately 230 CY of concrete. In addition to the pilings, the Washplant <br />building and the Thickener Tank have poured concrete floor slabs. The piers and floor for the Washplant and <br />Thickener required approximately 84.5 CY and 12.5 CY of concrete, respectively. The retaining wall for the <br />Reclaim Tunnel required approximately 30 CY of concrete, the piers for the Reclaim Tunnel required 36 CY of <br />concrete, piers for the various bents required 62.5 CY, and a transformer pad required 4 CY of concrete. During <br />construction of the Reclaim Tunnel and retaining wall, Ditch D -3 was relocated to the south. The ditch and culvert <br />sizing does not change as a result of this relocation. The locations of the referenced structures are shown on Map <br />24, Surface Facilities. <br />TR07 -59 2.05 -29 02/27/07 <br />