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Entry Borehole and pipeline will not require soil material salvage or modification of the existing drainage and <br />sediment control system. The borehole will be completed as a 16 -inch (maximum) diameter drillhole using <br />•conventional— drilling techniques, with air or-air /foam as the circulating medium. Using -air or air /foam, and-because- <br />the hole is so shallow, mud pits will not be required. A 12 -inch (maximum) diameter steel casing will be placed <br />and grouted in the drillhole. The borehole surface installation will be protected by a section of CMP, buried so that <br />2 -4 feet extends above ground level. The surface installation will be properly grounded to comply with applicable <br />MSHA requirements. One or more concrete - filled steel posts, extending four -feet above ground level will mark <br />and serve to further protect the surface installation. An 8 -inch (maximum) steel or welded HDPE transfer pipeline <br />connecting the Borehole to the existing Site 109 Discharge Pipeline will be trenched and buried approximately 6- <br />feet deep along the existing Haulroad. The pipeline will enter the Borehole below grade, and control valves will be <br />used to control flows. <br />Fish Creek Dewatering Boreholes, Treatment System, and Transfer Pipelines - At the Fish Creek Borehole <br />location, submersible pumps draw from an underground sump where mine water inflows, that have been intercepted <br />and routed underground, as shown on Map 16 (Mine Water Balance Map), collect. Coal fines slurry from the <br />Washplant Thickener Underflow Borehole also discharges to the underground mine water storage area. Prior to <br />entering the sump, the mine water and coal slurry decant water pass through an network of abandoned and sealed mine <br />workings which facilitate settling of any suspended solids prior to collection and pumping of mine water to the surface. <br />Installation of the original transfer /recycling system from the Fish Creek Dewatering and Water Treatment Facility <br />required the following activities: 1) Installation of a pumping system at Fish Creek Borehole facility, 2) Electrical <br />and control system modifications, 3) Installation and tie -in of a waterline from the western settling cell to the <br />Barricade Chamber/FCM -2 site, and 4) Installation of manholes along the waterline for installing "T's" for stock - <br />tank feeds. Installation of the pumping system required construction of a concrete pad as a foundation for the pump <br />and control building. The pad slopes towards the existing treatment cells, or a drain pipe may be installed, so that <br />any runoff from the pad will drain to the cells. A suction line from-the pump in the western settling cell allows <br />•treated mine water to be pumped to the Barricade Chamber or TORT waterline. Whether in mine water recycle or <br />direct discharge mode, the water treatment system will continue to function, to treat mine water for use <br />underground, or to meet applicable effluent limitations for direct discharge to Fish Creek. Direct discharge occurs <br />through a gated discharge pipe in the final treatment cell, with discharge to the outlet channel and flow <br />measurement flume discharging to Fish Creek at CDPS Outfall 115. The discharge line from the transfer pump <br />connects to the two mine water transfer pipelines (Fish Creek/Barricade Chamber, and Fish Creek/Area 1 Pit), with <br />valving to control flow and routing. <br />Fish Creek Treatment Ponds Discharge Pipeline (MR09 -237) - A new head -gate and pipeline will be installed at <br />outlet of the Fish Creek Treatment Ponds, and will control discharge through CDPS Outfall 115 to Fish Creek. The <br />new pipeline will replace the existing discharge pipeline, which has a sharp angle bend that is subject to clogging. <br />Discharge pipeline replacement is scheduled during the May 2009 longwall move, when water from the treatment <br />ponds will not be needed for underground operations. This will allow TCC to drain the pond to facilitate pipeline <br />replacement. The replacement pipeline will be 12 -inch welded PVC pipe, extending approximately 50 feet from <br />the treatment ponds to the Outfall 115 drainage channel. The new head -gate will be similar to the existing head - <br />gate. The location of the Fish Creek Treatment Ponds discharge pipeline is shown on Map 24 (Sheet 2 of 3). <br />The pump /control building was constructed on the concrete slab (approximately 12 x 20 x 2 feet) on the existing <br />berm, with limited fill on the west side of the existing cell embankment to establish a stable pad for slab <br />construction. Fill material was obtained from within the boundaries of the disturbed area or brought in from the <br />portal area. Once the new building was constructed, the building housing the acid -feed system was de- energized <br />and removed. The power -feed from the existing substation was then extended to the pump- station, requiring <br />installation of two additional powerpoles. All construction activities occurred within the previously disturbed area. <br />•The original mine water transfer pipeline to the Barricade Chamber/FCM -2 location was installed along the existing <br />road corridor, except for a segment that traverses the reclaimed and bond - released surface mine area. In areas <br />where the waterline was installed in the road corridor, the trench was excavated either down the center of the road <br />TR10 -73 2.05 -50a 05/21/10 <br />