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-y- The "E", "Wild", and "D" coal seams, which the applicant proposes to mine duriny this permit term, are all within the Upper Coal member. The "E" seam varies in thickness from 4.5 feet to over 12 feet, the "Wild" seam is from 5.5 feet to 10 feet thick and the "D" seam is from 6 feet to over 14 feet thick. Both the "E" seam and the "Wild" seam contain numerous shale splits. The upper most coal seam to be mined, the "E" seam, has an overburden thickness that ranyes from less than 400 feet at the portal to over 2,000 feet at the northeastern permit boundary. The total interburden thickness between the bottom of the upper "E" seam and the top of the lower "D" seam averages 140 to 160 feet. The coal seam overlying the "E" seam within the Upper Coal member, the "F" seam, will not oe mined at the Hawk's Nest Mine due to its erratic thickness and the presence of splits. Future mining at the Hawk's Nest Mine may expand to include the mining of the "C" and "B" seams located in the lower Coal member, below the "U" seam. The rock strata in the region dip uniformly at between 3 and 5 degrees to the north-northeast towards the axis of the Piceance Structural Basin. The gentle deformation which occurred in the region resulted in only minor faulting and fracturing. The faults which have been observed in the mines along the North Fork are high angle normal faults with low displacement. The North Fork and its tributaries have established channels along faults and fractures. Three aquifer systems exist within the general area; the alluvium and terrace deposits associated with the North Fork and its tributaries, the Rollins sandstone, and the discontinuous lenticular sandstones of the upper Mesaverde Formation. The alluvial aquifers are the most significant source of ground water for domestic, irrigation and industrial uses in the reyion. The only bedrock aquifer of sufficient regional extent and thickness to be of significance is the Rollins sandstone. Several wells are completed in the Rollins in the area of the Hawk's Nest Mine. These wells in the Kollins represent the only wells drawing water from bedrock aquifers in the region. The discontinuous lenticular sandstones of the upper Mesaverde Formation, (e.g., the power Coal, the Upper Coal and the Barren members) support only localized perched aquifers. These perched aquifers support the flows of the scattered springs located in the upper elevations. The coal seams are not aquifers. Mine inflows which have been encountered to date within the Hawk's Nest Mine are minor and localized in areas of faultiny and fracturing. Some weeping of the coal and roof strata occurs upon advance of mining, but the application indicates that this weeping stops within a week of mining in an area.