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600 million cubic feet of storage in the East Mine District (only assumes a 30 foot height in the gob area • and permeability of 25 percent). The source of hydraulic transport medium will be water from the thickener underllow. The water/solids mixture will be piped from the wash plant through a 4" FIDPE pipeline underground for 1,800 feet to the old 4"mine water borehole, see Map 24 for location of pipelines. The borehole pipe will then be connected to a 4" aluminum pipe on the mine floor for the remaining 5,000 feet to the mine gob seal. The pipe will be connected to the existing drainpipe at the seal where it will flow onto the mine floor behind the seals (gob side) and to the bottom of the gob area, Map 23 shows the area which will receive the underflow material. The water/ solids mixture will be pumped behind the seals where the fines will settle out and the water will travel to the submersible pump for dewatering back to the surface. The water is retained by the coal barrier as shown on the underground mine workings map. The retaining wall for this refuse storage area is a minimum 250-foot wide coal barrier between the EMD and the Northern Mining District. This barrier currently holds mine inflow water and contains a submersible pump at the low point for mine dewatering. This pump will be used to recycle water back to the surface for wash plant make-up water, recycled underground for dust suppression, or discharged directly into Foidel Creek. TCC understands that before this water can be discharged directly into Foidel Creek its existing discharge permit will have to be amended to allow for this activity. The water recycling/discharging system will require minor changes to the present water distribution system. Water pumped from the mine exits the mine at site 109. From this point the water will be piped over to the old pit where it will have time to settle and aerate. A pump station will be installed towards the south end of the old pit. This will involve burying forty-foot beams under the road and extending them over • the pit. The beams may be placed in concrete if additional weight is required to act as acounter-balance. A platform will be constructed on the beams extending over the pit. A submersible pump, along with hosing and piping, will be suspended from the platform into [he pi[. A winch will be installed on the platform to assist in setting the pump at the prescribed elevation. The water pumped from the pit can go in one of three directions, or a combination of them. The directions are as follows: 1) pit to Prep Plant, 2) pit to mine water recycling line, and/or 3) discharge to Foidel Creek. The water pumped from the pit will piped over to a de-sander, which will be located at an old well site, from this point it will be piped to the Prep Plant or piped over and tied into the existing mine water line. A line will be installed from the de-sander back to the pit so that the back flush water can be returned to the pit. The location of the lines is shown on Map 24, which also indicates where the trenches will be excavated for placement of the lines. The trenches will be dug with a backhoe or trackhoe, and during the excavating process suitable plant growth media will be removed and set to the side so that it can placed on top of [he subsoils returned to the trench. In reference to pumping directly into Foidel Creek, TCC will keep the water level in the pit thirty feet below the top of the high wall. The existing water in the pit will be pumped down to that level so that adequate storage is available to contain spring runoff in addition to the flow from site 19. By maintaining the water level below the thirty foot level a buffer is provided for "isolating" water pumped from site 109 into the pit. The plan is to pump water from site 109 into the pit and then water would be pumped out of the pit and either recycled to the Prep Plant or discharged directly into Foidel Creek. The pumping rate from the pond will typically exceed that coming from site 109. The ability to discharge directly into Foidel Creek will be dictated by water quality in Trout Creek and the status of the Fish Creek Borehole. The pump will require the installation of a transformer, concrete pad, and grounding bed. This installation • will be in a disturbed area; therefore, no topsoil salvaging will occur. The pad will be approximately 6' x 7' x 1'. A powerline, approximately 350' in length, and requiring two power poles, will be constructed from an existing line to this new location. TR 01-39 2.05-97.2 09/17/01