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As the West Elk Mine is an underground mine and most of the reclamation will not begin until <br />the end of the life of the mine, it is necessary to have subsoil and topsoil stockpiles. The main <br />topsoil pile is located to the south of the run-of--mine coal stackpad and will be used for <br />reclamation of the main mine facilities azea. Some subsoil from the subsoil pile in Sylvester <br />Gulch, (Live Subsoil Pile #1) as well as the topsoil from the stockpile at the North Soil Storage <br />Area (NSSA), will be used for reclamation of the Lower Refuse Pile. MCC has also stockpiled <br />topsoil from the Refuse Pile Expansion (RPE) area and the widening of the mine entrance at the <br />NSSA on the north side of Highway 133. <br />In 1997 and 1998, MCC employed several corrective measures to stabilize the landslide at the <br />main mine facilities azea, as surges of movement had been experienced in 1996 and 1997. The <br />corrective measures included the installation of rock buttresses, stone columns, horizontal drains, <br />pins (micro-piles), and the expansion of the roller compacted (RCC) buttress. These structures <br />are described in detail, and their effectiveness in improving the stability of the facilities azea is <br />discussed in Exhibit 14C, 1998 Landslide Corrective Measures Report by Barr <br />Engineering/Hazding Lawson Associates. The purpose of the corrective measures was to prevent <br />catastrophic failure, which MCC was successful in doing. MCC will continue to evaluate the <br />effectiveness of the corrective measures over time to evaluate their effectiveness for the long <br />term (i.e. post-reclamation). MCC is collecting water level data and movement data from <br />various piezometers, inclinometers, and survey mirrors azound the mine site on a scheduled <br />interval. Based on the data collected MCC will reevaluate the slope stability analyses after <br />spring runoff each yeaz and where appropriate, update Exhibit 14C. The update will include an <br />evaluation of the relative change in the factor of safety during the previous year and since the <br />installation of the corrective measures in 1998. A revision including the updated information <br />will be provided to the Division by July 30u' of each yeaz. <br />In the spring of 1999, MCC will drill two horizontal holes from the surface, at the abandoned <br />main mine site substation, to intercept small sumps in the F-Seam to drain the water that <br />accumulates in these sumps. The water that accumulates in these sumps is primarily surface <br />water and neaz surface groundwater that infiltrates through the colluvium above the F-Seam and <br />into the F-Seam workings. Once the water is in the sump, it then infiltrates through the F-Seam <br />floor and into the unstable surface soils within the main mine site landslide. It is important that <br />water sources to the surface soils be controlled in order to improve the local and global stability. <br />These two holes are a test to determine if this method of draining the sumps is feasible. These <br />sumps are located neaz the main F-Seam portals. They are not part of MCC's mine water <br />handling system. These sumps have not been nor will be used to handle a lazge inflow event. <br />The sumps are too small and if they overflow, they will flow into the belt and travel ways. Drain <br />A will be drilled approximately 1,100 feet and into the floor of one of the main collection sumps. <br />Drain B will be drilled approximately 1,400 feet, and into the bedrock fracture zone below the F- <br />Seam sumps. If the holes aze successful, MCC estimates that approximately 22 gpm will flow <br />from the two holes and into pond MB-1. If the holes aze successful, MCC will permit and <br />2.05-27 Revised Jan 1996 RN03; RevlsedNav. 1996 PR07; RevrsedJan. 1997 TR79; Revised/ul 1997 TR82 <br />Revised Oct. 1998 TR86; Revised Jun. 1999 TR90 <br />