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• Wadge Coal Water Levels. Thirteen monitor wells (CW-52W-1W, -2W, -3EW, -3W, -4W, -SW,
<br />-tOW, -13 W, -14 W, -15W, -16W, -17W, and -18W) have been completed as of October 7, ]989 to
<br />monitor water levels in the Wadge coal aquifer at Seneca II-W. Exhibits 7-1 and 7-3 show
<br />the Wadge coal monitor well locations and the poten tiometric surface for the Vladge coal
<br />aquifer, respectively.
<br />Water level data for Wells G14-52W-1W, -2W, -3EW, -3W, -4W, and -SW were collected from
<br />February and May of 1980 through 1986, 1985, 1983, 1989, 1986, and 1986, respectively.
<br />Water level monitoring at Wells 10W and 13W began in August, 1982 and at Wells 14W, 15W,
<br />16W, 17W, and 18W in October, 1987. Monthly water level data for the Wadge coal wells,
<br />including hydrogra phs, are presented in Appendix 7-2. Table 7-2 summarizes the well
<br />completion information for the nested Wadge coal wells.
<br />Wells 1W, 2W, 3EW, 3W, 4W, and SW were nested in the same boring as overburden and Wolf
<br />Creek coal wells (refer to well completions, Appendix 7-1). Based on field notes and
<br />observations, all were suspected of having leakage in the annular seals except Well 3W.
<br />lionito ring was thus discontinued at all but Vlell 3W. Table 7-4 is presented to show those
<br /> time periods for each well that the water level data is felt to be representative of
<br /> natural conditions. Significant portions of the water level records for Wells 1W, 2W, and
<br /> SW are believed to be invalid. For the following discussi on, only that portion of the
<br /> water level data believed valid will be interpreted and used to suppo rt any conclusions.
<br />Ground water in the Wadge coal aquifer occurs primarily under confined conditions. Wells
<br />10V, 14W, and 16W are completed in unconfined portions of the aquifer. In the confined
<br />portions of the Wadge coal aquifer, mean water levels range from +72.5 feet at Well 2W to
<br />292.2 feet below ground surface at Well 15W. Mean artesian heads range from 3.1 feet at
<br />Well 13W to 660.5 feet at Well 2W. In the unconfined portions of the aquifer, mean water
<br />levels range from 96.8 feet at Well lOW to 339.4 feet at Well 16W. Mean saturated
<br />thicknesses of the Wadge coal range from 10.3 feet to 13.8 feet in the confined portions
<br />of the aquifer and from 0.07 feet to .46 feet in the unconfined portions.
<br />The large range in water levels for the Wadge coal aquifer is a function of boring depths,
<br />completion intervals, proximity to outcrops, and topography. As can be seen from Table
<br />7-2, several of the nested Wadge coal wells are partly completed in the Wadge overburden
<br />and unde rburden, or only partly completed in the Wadge coal. A slight amount of overdrill
<br />is necessary to insure that the entire coal unit is open to the well. When 72 to 70 feet
<br />of overdrill occur, as in the case of Well 1W and BW, error can be introduced.
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