2009-08-10_PERMIT FILE - C1982056A (4)

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drill-rig will be used to complete and case the No. 2 Well. It is anticipated that air or water will be used as the primary circulation medium, with use of drilling mud only if required to maintain the integrity of the drillhole and . adequately flush drill cuttings. Cuttings and any drilling fluids will be retained in a portable cuttings pit. The No. 2 Well will be cased with welded steel casing, which will extend to within 10 feet of the abandoned and flooded EMD mine workings. The casing will be grouted in-place along its entire length, and a wellhead will be installed at the surface from which the pump will hang. A large-diameter CMP culvert will be cemented in-place around the well-head and fitted with a lockable cover. A multi-stage submersible pump will be installed in the well casing and connected to a power controller in the existing well house. The new powerline from Substation 11 will replace the existing powerline, bringing 12,470V power to the TORT Dewatering Installation Substation, where two transformers will convert the incoming power to 2,400V and feed power to the l ORT Dewatering Wells 1 and 2. The connecting pipeline tying to the 1ORT/FCM-2 Transfer Pipeline will be trenched and buried approximately 6 feet deep. The connecting pipeline will run from the new IORT Dewatering Well No. 2 to the IORT/FCM-2 Transfer Pipeline, and then parallel the pipeline for approximately 1,000 feet to the junction with the T0RT/6MN Transfer Pipeline. Flow in this pipeline section will be from the IORt Dewatering installation to the junction, and then back to the Barricade Chamber/FCM-s location. At this junction, a pre-fabricated CMP or concrete culvert will be installed as a manhole to provide access for pipeline control valves and inspection. A second discharge line will be extended approximately 3,900 feet from control valve manhole, to the south, extending under the 6MN Access Road, and discharging through the existing railroad culvert to Foidel Creek. The TORT Discharge Pipeline will be welded 12-inch HDPE pipe, buried approximately 5 feet deep, discharging through a riprapped discharge basin and channel to the existing culvert. For all pipeline construction, soil material will be removed and temporarily windrowed on one side of the trench, with trenched material placed to the other side. Once the pipeline is placed, properly bedded, connected to the 1 ORT/FCM-2 Transfer Pipeline, and leak tested, trenched material will be backfilled and compacted, and soil material will be replaced over the excavation and reseeded. It is anticipated that when the pipeline is no longer needed to support mining and related operations, it will be plugged below grade and abandoned in-place. Reclamation of the wells, when no longer needed, will involve plugging and sealing the • well consistent with approved sealing practices, consistent with applicable State Engineer requirements. TORT Monitoring Borehole Installation and Pumphouse Modifications (MR09-238) In order to accurately monitor water levels in the EMD sump area, TCC plans to drill and case a monitoring borehole at the IORT location. The new TORT Monitoring Borehole will be drilled on the existing TORT facilities pad, and will involve no new surface disturbance. The borehole will be collared with an 8-inch ID surface casing, extending to a depth of approximately 40 feet. The borehole will then be drilled as a 6.25-inch borehole to a depth of approximately 1,365 feet, and cased with 3-inch ID cemented in-place casing. The casing will extend approximately 4 feet above the ground surface, and be fitted with a locking cap to prevent unauthorized access. The 10-RT Monitoring Borehole will be used for regular monitoring of mine water levels in the EMD. When no longer needed to monitor water levels, the TORT Monitoring Borehole will be plugged and sealed in compliance with State Engineer requirements, the casing will be cut-off below grade, and the associated disturbance will be reclaimed along with the rest of the l ORT facilities area. The addition of the second l ORT Dewatering Borehole resulted in the need for changes to the pumping and control systems for the TORT dewatering installation. To accommodate pumping and control equipment for the two I ORT Dewatering Boreholes, the existing TORT Pumphouse and foundation pad will be demolished, and replaced with a larger Pumphouse and foundation pad with support piers. Specifically, the existing 16 x 14 foot wood-frame building and 14 x 24 foot concrete pad will be replaced by a 25 x 43 foot concrete pad with 12 - 1-foot diameter concrete piers extending to a depth of approximately 12 feet, and a 25 x 30 foot pre-fabricated steel building. The Pumphouse expansion will occur on the existing 10-Right facilities pad and will involve no new surface disturbance. Other associated work will include placement of the existing electrical transformer on the northeast corner of the new pad, and completion of the necessary plumbing and electrical hook-ups. When the pumping • installation is no longer needed to support ongoing or future operations, the l ORT Pumphouse, foundation pad, and associated equipment will be removed for salvage or demolished, and the associated disturbance area reclaimed along with the rest of the TORT facilities area. MR09-238 2.05-50.6 06/26/09