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the formations present on the Bourg property, but not necessarily in large quantities. Yields of existing wells in the vicinity of Bourg are low and the development of ground water for other than low rate uses is impractical. Twenty-eight exploration holes were drilled into the Coalmont Formation and eight holes were drilled into and through the Mann Draw alluvium to fix the location of the mineable coal seams (Geology, Section C of original application). Water level measurements were made in these holes after they were drilled and these are recorded in Table 1 of the original application. The locations of the drill holes are shown and the water elevations contoured on Plate 1 of the original application. The shape of the water level contours closely reflects the, geologic structure of the area. Ground water flow is generally from the southeast to the northwest within the Coalmont Formation and is greatly affected by the local fault pattern. The faults tend to act as barriers to ground water flow instead of conduits. The water levels measured, and shown in Table 1, are water levels in the Coalmont Formation. The Coalmont water levels indicate most of the water in the Coalmont occurs between the two mineable coals. The estimated volume of water within this portion of the Coalmont within the area that is to be mined is less than 2 acre-feet. (The method of calculating the stored volume is simply the specific yield [10%J times the volume of sediment as estimated from the cross-sections of Plate 3)• The water level contours also indicate the whole of the outcrop of the Coalmont on the property is a recharge area for the formation in the immediate vicinity of the mine. The volume of the aquifer recharged is limited by the discontinuity of the sandstone Lenses within the formation, ~' and the relatively low permeability of the Pierre Shale immediately below the Sudduth coal. 1 Z