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town of Somerset, Colorado, the width of alluvium increases while the thickness of alluvium <br /> decreases to about 35 feet. <br /> Since the three main minable seams (B, E, and F) on West Elk's property directly overlie <br /> one another, their structural characteristics are virtually identical. The F Seam strikes north <br /> 60 degrees west and dips three to five degrees northeast across the lease block. In the Jumbo <br /> Mountain area, the B S-am has an average dip of 4.6 degrees in a north 25 degrees east <br /> direction. The major cleat orientation within the F and B Seams is north 70 degrees east. <br /> This face cleat is prominent and consistent throughout the existing F and B Seam workings. <br /> Fracture sets and cleat orientations of the E Seam are also the same. The major cleat <br /> direction in the nearby Bear and Somerset [nines is from North 70 to 75 degrees east and is <br /> probably representative of the face cleat direction in the Jumbo Mountain area. <br /> In March 1996, MCC experienced a large inflow of water in the B East Mains while mining <br /> through a fault/fracture system. The inflow was estimated at approximately 350 gallons per <br /> minute (gpm) initially, increasing to a maximum of approximately 800 gpm from the roof <br /> and floor. The fault area is a series of small faults oriented in a N60°E direction. The fault <br /> showed an apparent vertical displacement of 6 feet. In April 1996, MCC encountered the <br /> same fault in a subsequent entry, the inflow was estimated to be a maximum of 2,500 gpm. <br /> The flows have since diminished. In May 1996, the flow was measured at approximately <br /> 240 gpm. The mine inflow and subsequent discharge of water will be thoroughly <br /> investigated by the Division during 1996. <br /> Only minor faulting of limited vertical displacement has been observed in the Blue Ribbon, <br /> Bear, and Hawk's Nest Mines. However, in the Orchard Valley Mine, a fault with a <br /> displacement of 50 feet was encountered during mining. Drill hole data indicate the presence <br /> of other faults in the lite-of-mine area with similar displacements. One major fault has been <br /> encountered in the Somerset Mine. The faults which have been encountered in existing <br /> mines tend to be high angle, normal faults. <br /> Hydrologic Balance - Rules 2.04.5, 2.04.7, 2.05.3(4), 2.05.6(3) and 4.05 <br /> Ground water information can be found in Section 2.04.7 of the permit document. <br /> Additional information can be found on Map 34 of the permit, which shows the location of <br /> the ground water monitoring stations and Map 35, which is a composite Barren Member well <br /> water level and spring elevation map. <br /> A description of ground water occurrence and mining impacts on ground water within the <br /> permit and adjacent areas can be found in the "Probable Hydrologic Consequences of <br /> Mining" section of this document and the "Cumulative Hydrologic Impact Study" document <br /> for this mine area. <br /> There are seven categories of potential aquifers that occur in the Somerset Coal Field. These <br /> are: 1) the alluvial and terrace deposits associated with the North Fork of the Gunnison <br /> River; 2) the localized, shallow alluvium along creeks tributary to the North Fork; 3) the <br /> discontinuous, lenticular and laminar sandstones of the Mesaverde Formation; 4) the Rollins <br /> Sandstone; 5) the coal seams; 6) shallow colluvial sur£icial deposits; and 7) fracture zones in <br /> bedrock. <br /> 9 <br />