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7 North Angle Dewatering Borehole - An additional dewatering borehole was drilled into the 7 North Angle of the <br />No. 5 Mine. The borehole was reamed out to a nominal 15 inch diameter and 12 3/4 inch steel casing was placed in <br />the hole. The annular space was grouted. A pump was installed to pump water from the 7 North Angle sump. The <br />capacity of the pump is approximately 400 gpm. The dewatering borehole was located on a pad approximately 100'x <br />100'. Approximately 18 inches of topsoil (550 cy) was salvaged from the pad. The well head was enclosed in a <br />building along with the control panel and chemical metering system. The building sits on a cement pad approximately <br />12' x 10' x 1' in size. An in-line static mixer was placed in the discharge pipe to facilitate mixing of the coagulant and <br />the mine discharge. The water was then discharged into ditch 9-D14. <br />A chemical metering pump will be used to inject the coagulant (Nalco 8852 or equivalent) into the discharge stream. <br />The system will be used only as needed, and it is anticipated that the system will have little if any usage. Past <br />experience with the No. 5 Mine sump indicates adequate settling access underground and coagulants are not needed <br />to meet discharge permit requirements. <br />As shown on Map 26, a sump will be excavated upstream of culvert 50. This will allow for settling of suspended <br />material prior to entering culvert. It is anticipated this will decrease maintenance work on this culvert. The pump will <br />be approximately 5' wide x 25' long x 2' deep. Therefore, approximately 10 cy of topsoil will be stockpiled adjacent to <br />the sump. The stockpiled topsoil will be stabilized with the appropriate seed mixture. <br />As shown on Map 26, two new culverts will be installed and they are identified as culverts numbered 50 and 51. The <br />design for these culverts is contained in Exhibit 18. Also, the design for ditch 9-D14 and modified ditch 9-D7 is <br />contained in Exhibit 18. <br />The mine discharge will flow through ponds 9-P2 and 9-P3. These ponds will allow 12.8 hrs. detention time in <br />addition to the sump settling time. The ditch between ponds 9-P2 and 9-P3 will be reconstructed and a ditch will <br />actually be cut in and conveyor belting laid in the bottom of the ditch. <br />In order to facilitate handling of the mine discharge, the upper section of ditch 9D-12 will be removed along with <br />culvert number 20. The ditches have been designed to handle the additional runoff from this area. <br />A powerline will be constructed between the existing YVEA line and the borehole. This extension is shown on Map <br />26. <br />9P-2 to 5A Waterline - RAG EC plans the installation of a buried 4" poly-pipe waterline, pump, pump, pumpshed, <br />intake line, and powerline extension at pond P-2. Water will be pumped from pond 9P-2 via the 4" buried line to <br />the existing water storage tank at the 5A portal area. From this tank, the water will be put through the existing <br />distribution system. Water is provided to Pond P-2 from the 7 North Angle mine dewatering pump. RAG EC plans <br />to install a skid-mounted pump along the south side of pond P-2. This pump will be protected by a metal or <br />wooden shed approximately 10' x V x 8'H, and will be surrounded by a six foot high chain link fence. Power will <br />be supplied to the pump by means of an extension from the existing powerline adjacent to the 5A access road to the <br />north of the pond. This powerline extension will entail the installation of 4 to 6 poles and the powerline will be <br />suspended from these poles. <br />An intake line will be placed in the pond, and will be fitted with a check valve and strainer head. Both the intake line <br />and the 4' receiving line will be buried to a depth of approximately six feet. The line will be buried using a trenching <br />machine, and will follow an existing two-toe of the access road outslope. A dozer may be required for ripping of <br />some short segments along the roadway to allow the trenching machine to install the line from the staging area over to <br />the 100,000 gallon tank. Approximately 6,090 feet of line will be installed, with a substantial portion of this being <br />required to allow the waterline to parallel the access road. <br />Due to the buried nature of the line, RAG Empire plans to leave most of the line buried in place during final <br />reclamation activities. It is planned that the pump, pumphouse, fence, intake line, and powerlines would be removed. <br />The ends of the buried line would be excavated, cut back, plugged, and backfilled. Line segments on the surface or <br />Permit Renewal RN08-05 2.05-14 01/15/09