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3. 4 foot diameter Temporary Shaft <br />A. The temporary shaft was originally drilled and cased with four -foot diameter steel casing. <br />B. The 83 foot deep shaft will be completely filled for the entire depth. <br />C. The first 50 feet from the bottom of the shaft will be filled with incombustible material. <br />D. Once the fill approaches the top of the shaft, the dirt will be excavated on the outside of the <br />steel casing so that it is below final grade. A diligent check for methane will be done and the <br />steel casing will be cut off below grade. <br />E. The area will then be backfilled to final grade. <br />4. 16 -foot diameter Elk Creek Intake Shaft, Fill Material Plug <br />A. The intake shaft was originally constructed in an open cut excavation. Ring beams and liner <br />plate were installed and grout was pumped behind the liner plates. Additional liner plates were <br />installed as a barrier around the shaft to an approximate height of four feet above the collar. <br />B. Oxbow proposes to fill the shaft to an approximate height of 50 feet above the mine floor <br />elevation with incombustible material. This will isolate the mine workings from the rest of the <br />shaft and allow a safer work environment around the collar for final sealing. <br />C. The initial amount of fill material required to reach the roof of the mine workings may be up to <br />180 cubic yards. This material will be stockpiled near the shaft so that filling will be <br />continuous for the initial 15 feet of height. <br />D. Filling of the shaft may be done by a front-end loader or end -dump haul trucks. In either case, <br />a substantial berm or stop blocks will be placed to prevent wheel travel near the edge of the <br />shaft. <br />E. While working around the shaft collar, workers shall be restrained by a substantial barricade, <br />or they shall be tied off. <br />F. Once the initial plug of material is in place, workers will switch over to the Elk Creek Return <br />Shaft. <br />G. In order to fill the shaft, it may be necessary to remove a small section of liner plate that is <br />sitting above the shaft collar. At times when no one is working to fill the shaft, the shaft edge <br />will be adequately fenced or protected and posted with conspicuous signs prohibiting the <br />entrance of unauthorized persons. <br />5. 16 -foot diameter Elk Creek Return Shaft, Fill Material Plug <br />A. The return shaft was originally constructed in an open cut excavation. Ring beams and liner <br />plate were installed and grout was pumped behind the liner plates. Currently, the Elk Creek <br />main fan housing sits on the shaft collar and surrounds the shaft opening. <br />B. Oxbow proposes to fill the shaft to an approximate height of 50 feet above the mine floor <br />elevation with incombustible material. This will isolate the mine workings from the rest of the <br />shaft and allow a safer work environment around the collar for final sealing. <br />C. The initial amount of fill material required to reach the roof of the mine workings may be up to <br />180 cubic yards. This material will be stockpiled near the shaft so that filling will be <br />continuous for the initial 15 feet of height. <br />D. Filling of the shaft may be done by a front-end loader or end -dump haul trucks. In either case, <br />a substantial berm or stop blocks will be placed to prevent wheel travel near the edge of the <br />shaft. <br />E. While working around the shaft collar, workers shall be restrained by a substantial barricade, <br />or they shall be tied off. <br />F. A portion of the fan plenum will be removed to allow access to the shaft. <br />G. Once the initial plug of material is in place, workers will alternate filling the return shaft and <br />the intake shaft until the final height of approximately 50 feet is reached. <br />3 <br />