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VI. Hydrologic Balance: Ground Water - Rules_2.04.5,_2.04.7L_2.05.3_and_4.05 The operator has presented sufficient information to describe the ground water regime in the vicinity of the Canadian Strip Mine. This information may be found in Appendix C, Volumes I and II of the permit renewal application. The entire outcrop and sub-crop of the Sudduth Coal seam near the mine and adjacent areas comprises the recharge area for the coal seam. Snowmelt provides the majority of the recharge to the coal seam. The estimated recharge over the entire coal seam was calculated to be 4,75 acre ft/y r. No wells are located in the Sudduth Coal seam, and there is only one discharge point in the area, a spring at the 01d Sudduth Mine located in Section 15, i T9N, R78W. This spring does not provide sufficient discharge to be considered a significant water source. There have been no other observed springs or seeps from the Sudduth Coal seam in the adjacent area. The Sudduth Coal seam does not appear to discharge to or be recharged by the alluvium of Williams and Bush Draws, This is evident from water table elevations which are lower in the coal seam than in adjacent alluvial wells. In a study by the U. S. Geological Survey, Hoffstra conducted aquifer tests and reported permeability values of 0.37 gpd/f t2 in unfaulted overburden, and 7.5 gpd/ft2 near faulted overburden. These values indicate that the overburden is essentially a confining unit, but approaches a semi-confining state in areas of secondary permeability, The upper Coalmont Formation contains limited perched aquifers. These perched systems typically consist of lenticular channel sands, usually less than thirty feet thick. An adjacent operation conducted an aquifer test of the underburden (upper Pierre Shale) near the mine site. From this test, the permeability of the underburden was calculated to be 0.15 gpd/ft2. A Sudduth Coal seam observation well located 20 feet away from the test hole showed no drawdown during pumping of the test hole. This data indicates that the Pierre Shale is a confining unit that transmits little water. The test also demonstrates that the Sudduth Coal is not hydraulically connected to the underlying Pierre Shale. One spring has been identified near the permit area. This spring issues from the contact between unconsolidated upland terrace deposits and the underlying Coalmont Formation. This spring is located in an area adjacent to the Canadian Strip Mine on a small tributary of the North Fork of Bolton Draw. This spring feeds a small pond used for stock and wildlife watering. This spring will not be affected by mining or reclamation activities since it is located outside the permit boundary upslope of the operation. Monitoring A hydrologic monitoring program was implemented at the Canadian Strip Mine in 1980. The extent of this program was revised on November 18, 1985. ) Monitoring, as defined in Stipulations 8, 9, 11 and 12 of the original permit, ~ (~ was reduced to monitoring of ground water in the Pit 1 area. The current ~ program consists of monitoring water level and selected water quality r , 1 a, ~ . . _, ~ " ~ ' ~ " _ ! _ 9 '