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fracturing associated with mine development. To date, only <br />very minor, unmeasurable water inflow has occurred up to this <br />time in the No. 2 mine tunnel, and none in the No. 1 tunnel. <br />This is due in part to the cessation of operations at the site <br />since 1987. Portals No. 1 and No. 2 have only been partially <br />drilled (613 feet and 576 feet respectively) into the Mancos <br />shale. Therefore, it is highly unlikely that the tunnels have <br />modified the groundwater conditions. <br />Another predicted impact of the Coal Ridge No. 1 operation was <br />water quality degradation (due to natural Seeps found in the <br />area) associated with the refuse disposal area. This site was <br />dropped from the permit and a new refuse pile has been approved <br />through Technical Revision 08. The temporary refuse area will <br />not exceed 15,000 cubic yards and will be inspected quarterly. <br />(See page 4-35 to 4-36 in the permit.) <br />The major movement of ground water within the area is <br />controlled by the steep dip, with movement southward toward the <br />central Piceance Basin. Cross communication of ground water <br />between the sandstones and the coal units is limited by the <br />thick interbedded shales present throughout the geologic <br />units. The deep basinal system inhibits ground water <br />development in much of the area because of the associated high <br />drilling and pumping costs. <br />Four bedrock zones which are either water-bearing or <br />potentially water-bearing have been identified in the permit <br />area. All four zones are in the Mesaverde Group. These units <br />are the Rollins Sandstone, the Wheeler Coal, and the Upper and <br />Middle Sandstones. Several wells were drilled through these <br />zones in the mine area by the applicant to evaluate the ground <br />water resources. Ground water was not identified in the Middle <br />and Upper sandstones in the permit area. <br />Groundwater was identified in both the Rollins Sandstone and <br />Wheeler Coal unit. The Rollins Sandstone is between 80 and 150 <br />feet thick in the permit area and is composed of a light gray, <br />moderately indurated, massive quartz sandstone. A minimum of <br />fractures were identified in core. In the permit area, this <br />unit was saturated below an elevation of 6060 feet. The yield <br />at one well was 4 gpd/ft., with a transmissivity of 50 gpd/f t. <br />Drill data showed that the Wheeler Coal is saturated in only <br />the deepest portions of the permit area, below an elevation of <br />6,080 feet. The groundwater yield in the Wheeler Seam is <br />estimated to be less than a few gpm, with a transmissivity <br />estimated of less than 100 gpd/ft. <br />Due to minor fracturing within the Wheeler Coal Seam and the <br />Rollins sandstone, there is some potential that ground water <br />could cross-communicate between these two seams. However, <br />neither of these rock units are utilized for ground water <br />within the vicinity of the mine and, due to the extreme dip on <br />_lg_ <br />