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_P7_ colluviaT/alluvial cover, the aquifer potential of the Deep Creek alluvium/colluvium is minimal. The importance of the material is that it aids in the recharge of the underlying Fruitland and by contributing some baseflow to Deep Creek by transporting water from the ridge crests and sideslopes. The major component of ground water flow in Deep Creek Canyon is postulated to be to the northwest, toward Stollsteimer Creek. Some of the ground water also flows downdip to the southwest, probably in the Fruitland coals. One monitoring well in Deep Canyon (D3-W/W-17) is located downgradient from the proposed mining operations. Continued monitoring of this well should indicate what, if any, impacts mining will have on the local flow regime. The regionally extensive Pictured Cliffs sandstone is far enough below the "B" seam so as to preclude its disturbance. No activity associated with "B" seam removal should induce hydrostatic pressures capable of disrupting the Pictured Cliffs flow system. The Division feels that some ground water will be encountered when angering along the south and southeastern highwalls of Pit 1R2. If water is encountered during any part of the mining operation, it must be diverted to a sediment pond where it will either be lost to evaporation or discharged into Oeep Creek when it meets NPDES effluent standards. A permanent overburden stockpile with two underdrains will be established upgradient of Deep Creek. If the drainage system functions as designed water percolating through the pile will be intercepted and routed out of the pile to a sediment pond. If the drainage system does not function according to plan, an unconfined aquifer may develop within the pile, or springs and seeps will be established along the base of the pile. Wells will be placed in the stockpile to determine how effectively the drainage system works. These wells will be used to monitor the development of a spoils aquifer, and the quality of that water. If an aquifer should develop, water issuing from springs and seeps at the base of the stockpile will be diverted via ditches to a sediment pond. The major effect of mining on the local ground water system will be from the infiltration of overland flow into the backfilled pits. This will slightly affect both the quantity and quality of ground water in and near the canyon. The relatively high permeability of the backfill will induce inflow into these areas. Therefore, a localized unconfined aquifer will develop in each pit. This development will probably continue until hydrostatic pressures allow these pits to recharge the Fruitland Formation, thus increasing the amount of locally available water. The quality of this water will not be the same as in the pre-mining condition, however, cumulative quality impacts to even the local Fruitland aquifer system will be minimal due to dilution and to the low transmissivity and hydraulic conductivity characteristics of the Fruitland. The cumulative effects of the Chimney Rock Deep Creek mining operations on the local ground water systems will be negligible. Aquifer characteristics, recharge potential, and limited areal extent of mining preclude any major impacts to the Fruitland Formation, the colluvial/alluvial system, Pictured Cliffs Sandstone or the Stollsteimer Creek alluvial aquifer.