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marine origin and, as a result, the sandstones and the coals are highly lenticular, discontinuous, <br />and of limited lateral extent in outcrop. This unit ranges up to 1,500 feet thick and outcrops <br />throughout most of the five-year permit area. <br />The Ohio Creek Member is the uppermost member of the Mesaverde Group. This unit is <br />approximately 700 feet thick and consists primarily of interbedded sandstone, mudstone, and <br />shale. The sandstones range from a few feet to more than 100 feet in thickness and are generally <br />lenticular in nature. Although typically fine to coarse grained, the sandstones may locally be <br />conglomeratic. <br />The Mesaverde Formation is unconformably overlain by the Tertiary Age Rudy or Wasatch <br />Formation. This formation consists of red to buff-colored shales, red sandstones, and red to gray <br />conglomerates. The sediments of this formation are weathered volcanic rocks. <br />The alluvium of the North Fork of the Gunnison River consists of Quaternary Age deposits of <br />mixed coarse sand, cobbles and boulders. These coarse sediments are composed primarily of <br />igneous and metamorphic rock types, and have their source area in the headwaters and upper <br />reaches of the North Fork. This coarse alluvium is capped by finer sands and silts. The North <br />Fork alluvium in the area of the Hawk's Nest, Bear, West Elk and Elk Creek Mines is fairly <br />narrow in width and is between 50 and 70 feet thick. About a mile below the town of Somerset, <br />Colorado, the width of alluvium increases while the thickness of alluvium decreases to about 35 <br />feet. <br />Since the three main minable seams (B, E, and F) on West Elk's property directly overlie one <br />another, their structural characteristics are virtually identical. The F Seam strikes north 60 <br />degrees west and dips three to five degrees northeast across the lease block. In the Jumbo <br />Mountain area, the B Seam has an average dip of 4.6 degrees in a north 25 degrees east direction. <br />The major cleat orientation within the F and B Seams is north 70 degrees east. This face cleat is <br />prominent and consistent throughout the existing F and B Seam workings. Fracture sets and <br />cleat orientations of the E Seam are also the same. The major cleat direction in the nearby Bear <br />and Elk Creek mines is from North 70 to 75 degrees east and is probably representative of the <br />face cleat direction-in the Jumbo Mountain area. In the southeast corner of the permit area, the <br />data show that the beds level out, becoming virtually flat-lying. <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 and <br />floor. The fault area is a series of small faults oriented in a N60E direction. The fault showed an <br />apparent vertical displacement of 6 feet. In April 1996, MCC encountered the same fault in a <br />subsequent entry, and the inflow was estimated to be a maximum of 2,500 gpm. The flows have <br />since moved down-dip on the fault and were measured at less than 100 gpm in December 1998. <br />In January 1997, more than 8,000 gpm of water upsurged from the mine floor from a 10-foot cut <br />through a fault area in the first Southeast Headgate off the Box Canyon Mains. Water flooded <br />the mine and some equipment was lost. Water from this inflow was eventually pumped to the <br />surface and discharged to the North Fork of the Gunnison River. Mine water inflow from this <br />9