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-5- The entire outcrop and sub-crop of the Sudduth Coal seam in the mine plan and adjacent areas comprises the recharge area for the coal seam. Snow melt 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 Old Sudduth Mine located in Section 15, 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 (Map 15a and Table 8a of the original permit application) which are lower in the coal seam than in adjacent alluvial wells. Hoffstra, who conducted aquifer tests in the overburden, reported permeability values of 0.37 gpd/ft2 in unfaulted overburden, and 7.5 gpd /f t2 near faulted areas. 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, which is located near the axis of the Johnny Moore Syncline, contains limited perched aquifers. These perched systems typically consist of lenticular channel sands, usually less than thirty feet thick. Kerr Coal Company conducted an aquifer test on the underburden (upper Pierre Shale) near the mine site. From this test, the permeability of the underburden was calculated to be 0.15 qod/ft2. In addition, a Sudduth Coal seam observation well located 20 feet ~vay 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. The Sudduth Coal seam, underburden and overburden units of the open Pit No. 3 are in hydrologic communication with the alluvium of Sudduth Draw. The bottom of open Pit No. 3 will be 120 feet below the level of Sudduth Draw. The pit will be dewatered during mining. These factors will produce an increased ground water gradient for flow from Sudduth Draw towards the pit, resulting in a depletion of flow in Sudduth Draw. This depletion can be minimized by decreasing the infiltration over the sub-crop in Sudduth Draw. Two stock ponds, one upstream and one over the sub-crop, exist on Sudduth Draw. These ponds increase the amount and the length of time that surface waters can infiltrate the alluvium, as is evident from the sub-irrigated area below the ponds. Water, which is allowed to infiltrate through the ponds upstream and over the sub-crop area, will be lost to beneficial use in the immediate area and downstream during and after mining the northern section of Pit No. 3. To resolve this concern, the following stipulation was necessary: