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Mountain Coal Company Exhibit 69 <br />West Elk Mine Sylvester Gulch Facilities. <br />• Excavation and handling of the soil, waste rock and coal from the exhaust shaft <br />construction will proceed in a similar manner, and the exhaust shaft will be lined with a <br />12" thick concrete lining concurrent with excavation. A water handling system will be <br />constructed between the concrete liner and the rock. During construction, groundwater <br />seepage will be dvected downward to the shaft bottom until it reaches the active working <br />face. Water encountered by the contractor during construction of the shafts will be <br />pumped out of the excavation at a rate not to exceed 25 gallons per minute and will be <br />directed to the sediment control ditch along the south side of the benches and then to the <br />SG-1. MCC contracted with Hydro-Geo Consultants, Inc. to perform hydrologic testing <br />on exploration hole EER during August of 1996. This exploration hole is located <br />approximately 50 feet south of the proposed exhaust shaft location. A total of 11 packer <br />permeability tests were conducted by Hydro-Geo covering the entire length of the hole <br />from the surface to a point just below the bottom of the B-Seam. Permeability tests were <br />performed using the constant head injection method. <br />The conclusions of the Hydro-geo study are: <br />1. During construction of the shafts, from the surface to approximately <br />400 feet in depth the maximum total inflows from the strata <br />encountered will be approximately 6 gpm to 8 gpm. <br />2. During construction of the shafts, as the shafts are deepened from <br />400 feet to the final approximate 700 foot depth, the maximum total <br />inflows will increase from approximately 8 gpm to 25 gpm. <br />3. Long-term steady state inflows to the shafts (and ultimately to the <br />shaft water collection system} aze not expected to exceed 20 gpm. <br />Once construction of the shafts is completed, the water handling system behind the <br />concrete liner will collect and convey seepage behind the liner down to the B-Seam where <br />it will be directed to a mine sump. This water will then be handled by the mine <br />dewatering system. Upon completion of construction of both shafts the contractor will <br />construct the concrete foundations and steel structures for the elevator, emergency hoist, <br />hoist building, fans, ductwork, Fan motor houses and standby generator for the fans. The <br />contractor will back-fill, compact, re-grade, and re-gravel, if necessary any areas disturbed <br />on the benches during construction, and return all drainage surfaces to their original <br />configuration prior to shaft construction. No excess waste rock, soil or coal will remain at <br />the shaft site after the permanent facilities are completed. <br />Construction of the roads, substation, powerlines, and shaft site benches will occur in one <br />construction season. Construction of the shafts will occur over approximately 18 months, <br />spanning two construction seasons. These facilities will be built for life-of--mine service, <br />which is estimated to be approximately 25 years. <br />12 Nov 1996 PR07R; ReviredMay 1997MR216: <br />RevrsedJal. l997MR219 <br />