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pit is reclaimed, a spoils aquifer will begin to develop. The water necessary to recharge this aquifer will be derived from precipitation, overland flow, and discharge from the Williams Fork formation overburden and the Wadge coal. The backfilled pits in and of themselves will display unconfined conditions, however the pits will be surrounded on the sides and be underlain by relatively confining units. The underlying material will be even more confining than the sides. As water enters the reclaimed areas it will tend to migrate through the spoils toward the lowest point in the pit. While some of this water may be lost to the walls, the major portion of it will stay in the pit, as the permeability of this material is greater than that of either the walls or the floor. It is projected that the water quality of spoil aquifers at the Seneca II-W Mine site will approximate that at the nearby Seneca II Mine. The Seneca II Mine spoil aquifers exhibit elevated levels of, total dissolved solids, magnesium, manganese, molybdenum, and sulfate. Complete water quality analyses of two spoils aquifer wells are published in the Seneca II Mine 1984 Annual Hydrology Report, Appendix B. As the aquifer is developing, the water will be of slightly poorer quality than the above assumptions, but as the more easily leached constituents are lost, the quality should approximate that at Seneca II Mine. Analysis of spoils water from the Seneca II Mine indicates that this magnesium-calcium sulfate water has elevated levels of sulfate and magnesium. TDS values vary between 2,200 and 4,000 mg/1. Eventually, water at Seneca II-W Mine will begin to discharge to the surface as the water elevation exceeds the ground level or when sufficient head is developed. This discharge may be contained in a sediment pond, or may flow into Hubberson Gulch along the access road. As previously discussed under short-term effects of elevated levels during mining, the elevated levels for sulfate, magnesium and TDS should not preclude the use of the waters of Hubberson Gulch from any of its current uses. As the distance from the mine increases the effects of dilution will improve the quality of water and eventually no effects from mining will be detectable. If the spoils discharge flows into the unnamed gulch along the access road, the water will cause the gulch to flow or will infiltrate into the associated alluvial/colluvial material. This is dependent upon the water table elevation in the gulch. If the spoils water inFiltrated the colluvium/alluvium it will flow toward Hubberson Gulch. If the spoils discharge causes the gulch to flow, this water will mix with any flow that is in Hubberson gulch. When the spoil springs discharge, Seneca Coal Company predicts Hubberson Gulch will have a TDS average of 2,193 mg/l. This in turn would result in an average 2,245 mg/1 TDS in Dry Creek, below 30