2010-06-04_PERMIT FILE - C1982056A (9)

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and grouted in the drillhole. The borehole surface installation will be protected by a section of CMP, buried so that 2 -4 feet extends above ground level. The surface installation will be properly grounded to comply with applicable • MSHA requirements. One or more concrete - filled steel posts, extending four -feet above ground level will mark and serve to further protect the surface installation. An 8 -inch (maximum) steel or welded HDPE transfer pipeline connecting the Borehole to the existing Site 109 Discharge Pipeline will be trenched and buried approximately 6- feet deep along the existing Haulroad. The pipeline will enter the Borehole below grade, and control valves will be used to control flows. Fish Creek Dewaterin Borehole;. Treatment S stem and Transfer Pipelines - At the Fish Creek Borehole location, submersible pumps draw from an underground sump where mine water inflows, that have been intercepted and routed underground, as shown on Map 16 (Mine Water Balance Map), collect. Coal fines slurry from the Washplant Thickener Underflow Borehole also discharges to the underground mine water storage area. Prior to entering the sump, the mine water and coal slurry decant water pass through an network of abandoned and sealed mine workings which facilitate settling of any suspended solids prior to collection and pumping of mine water to the surface. Installation of the original transfer /recycling system from the Fish Creek Dewatering and Water Treatment Facility required the following activities: 1) Installation of a pumping system at Fish Creek Borehole facility, 2) Electrical and control system modifications, 3) Installation and tie -in of a waterline from the western settling cell to the Barricade Chamber/FCM -2 site, and 4) Installation of manholes along the waterline for installing "T's" for stock - tank feeds. Installation of the pumping system required construction of a concrete pad as a foundation for the pump and control building. The pad slopes towards the existing treatment cells, or a drain pipe may be installed, so that any runoff from the pad will drain to the cells. A suction line from the pump in the western settling cell allows treated mine water to be pumped to the Barricade Chamber or l ORT waterline. Whether in mine water recycle or direct discharge mode, the water treatment system will continue to function, to treat mine water for use underground, or to meet applicable effluent limitations for direct discharge to Fish Creek. Direct discharge occurs through a gated discharge pipe in the final treatment cell, with discharge to the outlet channel and flow • measurement flume discharging to Fish Creek at CDPS Outfall 115. The discharge line from the transfer pump connects to the two mine water transfer pipelines (Fish Creek/Banicade Chamber, and Fish Creek/Area 1 Pit), with valving to control flow and routing. Fish Creek Treatment Ponds Discharge Pipeline (MR09 -237) - A new head -gate and pipeline will be installed at outlet of the Fish Creek Treatment Ponds, and will control discharge through CDPS Outfall 115 to Fish Creek. The new pipeline will replace the existing discharge pipeline, which has a sharp angle bend that is subject to clogging. Discharge pipeline replacement is scheduled during the May 2009 longwall move, when water from the treatment ponds will not be needed for underground operations. This will allow TCC to drain the pond to facilitate pipeline replacement. The replacement pipeline will be 12 -inch welded PVC pipe, extending approximately 50 feet from the treatment ponds to the Outfall 115 drainage channel. The new head -gate will be similar to the existing head - gate. The location of the Fish Creek Treatment Ponds discharge pipeline is shown on Map 24 (Sheet 2 of 3). The pump /control building was constructed on the concrete slab (approximately 12 x 20 x 2 feet) on the existing berm, with limited fill on the west side of the existing cell embankment to establish a stable pad for slab construction. Fill material was obtained from within the boundaries of the disturbed area or brought in from the portal area. Once the new building was constructed, the building housing the acid -feed system was de- energized and removed. The power -feed from the existing substation was then extended to the pump- station, requiring installation of two additional powerpoles. All construction activities occurred within the previously disturbed area. The original mine water transfer pipeline to the Barricade Chamber/FCM -2 location was installed along the existing road corridor, except for a segment that traverses the reclaimed and bond - released surface mine area. In areas where the waterline was installed in the road corridor, the trench was excavated either down the center of the road or along the shoulder. Field conditions dictated the location of the trench excavation. Up to five manholes are • located along the waterline, with installed "T's" to provide taps for setting up feeder -lines to deliver water to stock tanks. All of the installations are of similar construction, with a 5 -foot diameter culvert with insulated lid for manhole access, and a valve and "T "- connection to the waterline. Any feeder -lines will run overland from the TR09 -70 2.05 -50a 11/16/09