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Fracture sets and cleat orientations of the E Seam are also the same. The major cleat direction in <br /> the nearby Bear and Elk Creek mines is from North 70 to 75 degrees east and is probably <br /> 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 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 /> area also moved down-dip as the fault was mined through at topographically lower locations. At <br /> the end of 1998, the flow was approximately 130 gpm. <br /> A significant fault oriented in a S60E direction was encountered by MCC during the initial <br /> development of the Sunset Trail Mains in early 2018. No significant inflows of water occurred. <br /> The fault is projected to the southeast on Map 9, but has not yet been well characterized. <br /> Only minor faulting of limited vertical displacement has been observed in the Blue Ribbon, Bear, <br /> and Hawk's Nest Mines. However, in the Bowie#1 Mine, a fault with a displacement of 50 feet <br /> was encountered during mining. Drill hole data indicate the presence of other faults in the West <br /> Elk Mine life of mine area with similar displacements. One major fault has been encountered in <br /> the Elk Creek Mine. The faults which have been encountered in existing mines tend to be high <br /> 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 /> Groundwater information can be found in Section 2.04.7 of the PAP. Additional information can <br /> be found on Map 34, which shows the location of the groundwater monitoring stations. <br /> A description of groundwater occurrence and mining impacts on groundwater within the permit <br /> and adjacent areas can be found in the "Probable Hydrologic Consequences of Mining" section <br /> of this document and the "Cumulative Hydrologic Impact Study" document for the North Fork of <br /> the Gunnison area. <br /> There are seven categories of potential aquifers that occur in the Somerset Coal Field. These are: <br /> 1)the alluvial and terrace deposits associated with the North Fork of the Gunnison River; 2) the <br /> localized, shallow alluvium along creeks tributary to the North Fork; 3)the discontinuous, <br /> lenticular and laminar sandstones of the Mesaverde Formation; 4) the Rollins Sandstone; 5) the <br /> coal seams; 6) shallow colluvial surficial deposits; and 7) fracture zones in bedrock. <br /> Significant hydrogeologic units present within the West Elk Mine permit boundary include (from <br /> top to bottom) the Mancos shale, the Mesaverde Formation(including the Rollins Sandstone, <br /> 18 <br />