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piezometric head about equal to that observed in all strata above, The observation of approximately equal piezometric heads in all water bearing strata from the Trout Creek Sandstone to the surface at a particular locale is not completely understood. It is probable that vertical hydraulic communication between strata is sufficient to keep the piezometric heads approximately equal on a particular vertical line, given the very long time intervals available for equilibration. Regardless of the explanation, approximately equal piezometric heads in different strata makes it possible to assign a single value to the piezometric surface at a particular point, and therefore, permits the measurement of head in a specific . interval to be assigned to the over-all stratigraphic profile. Based on the above reasoning, all piezometric surface data available to 'us was utilized to prepare a regional piezometric surface map. Wells as far north as Energy Fuels' Pit No. 3 were utilized as were several points along the Trout Creek valley up to the.most southwest extent of the Pittsburgh 5 Midway Edna Mine. The average static water levels were used regardless of the specific completion details of individual wells. An important feature of this map is that it appears the piezometric surface elevation is • largely controlled by the elevation of Trout Creek on the east and south. In the vicinity of Energy Fuels' Pit No. 3, the piezometric surface is a few feet above Trout Creek. As indicated previously, there are no data directly in the area to be mined by Sunland and the piezometirc surface elevation in the vicinity of the Apex Mine was established by extrapolation and the assumption that' the piezometric surface elevation along Trout Creek continues to be controlled by the stream elevation (approximately). The piezometric surface elevation directly to the .north of the Apex Mine was estimated from a flowing well with no casing.(*1) It is not possible to determine from which interval the water is flowing, but the apparent value of piezometric head at this point fits well with that value extrapolated from measured points. Futhermore, since this well penetrates strata below the Trout Creek Sandstone, it provides additional evidence that the piezometric heads measured in overlying strata may be representative of that in the underlying rocks. The superposition of coal and piezometric surface elevations show that most of the coal .to be mined lies :.above the piezometric surface. All of the Upper Pinnacle seam within the lease boundaries in fault blocks 1. and 2 . lies above the piezometric surface. The areas in which the coal apparently .lies below the piezometric surface are: Rev; 4-22-81