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<br />• coal seams and remnants of tidal channels which had limited permeability <br />and were only unilaterally continuous. Groundwater movement was <br />northeastward toward the Watering Trough Syncline. Localized anomalies in <br />direction of groundwater movement were caused by local variation in <br />structure (i.e., rolls) due to differential compaction of interbedded <br />lenses of sandstones. Increased fracturing of strata and cleating in coal <br />seams at the apex and troughs of the rolls caused localized variations in <br />groundwater yield from a given coal seam and allowed vertical hydraulic <br />contact between coal seams. Further evidence of vertical permeability <br />between the coal seams within the zone that was mined was indicated by <br />visual observation of filled fractures in the highwall that were <br />persistent through the coal seams (i.e., rock spars in the coal). The <br />vertical hydraulic contact within the mining zone and subsequent mixing is <br />likely the reason there was little difference seen in water quality from <br />seam to seam in the mined interval. With the sedimentary and structural <br />environment present in the area, it is just as likely that small <br />variations in quality seen from seam to seam could have been encountered <br />• from one location to another location within the same seam. <br />WATER MONITORING PLAN <br />Due to site conditions mentioned above, it is evident the coal zone that <br />was mined and the adjacent area outside the area that was mined, but <br />containing the same coal zone, acts as a single groundwater system with a <br />composite quality derived from variations in overburden material <br />(vertically and laterally) and variations in coal chemistry. Water <br />movement from the zones is directed several miles northeastward into the <br />Watering Trough Syncline where the water is either available to recharge <br />the Big White and Twentymile sandstone through downward percolation in the <br />fractured syncline or water is lost to springs and seeps as outcrop <br />patterns dictate. <br /> <br />3265h/ <br />(2) <br />