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The colluvium is at a higher elevation than the mine (using a 21o angle of draw for subsidence related fracturing), therefore, no fracturing should intercept slumps in the Gulch. Colluvium in the first ephemeral drainage above the proposed portal could be dewatered due to subsidence fracturing, however, since this system is very limited in extent, effects would be minimal. The major effect from mining will be portal discharges due to subsidence after abandonment. This effect is already occurring in the permit area. The applicant observed discharge from the Victory No. 1 portal during the summer of 1984 indicating limited but sustained flow from an underground source. The maximum observed flow has been 25 gal/min during the spring months. This flow drops during the summer. The cause of this flow is thought to be subsidence intercepting the Cliff House Sandstone aquifer. The total effect of locally dewatering portions of the Cliff House Sandstone and colluvial slumps in the ephemeral tributary to Coal Gulch are probably negligab]e. The Cliff House down Qradient from the mine is not used as a source of water, and no springs issuing from it have been identified. The colluvial slumps in the ephemeral drainage contribute "base flow" to the drainage, but the entire drainage is a relatively minor tributary to Coal Gulch. Seeps issuing from the Menefee coals at coal/sandstone-shale contacts were observed during the spring of 1985. These seeps were evident along Highway 160 in the Coal Gulch area and along the highwall of the proposed mine site. Mining will encounter some water in the coal, though this water is seasonally variable in amount. The amount of water which will be encountered in the coal will be minimal, and could be used in normal mine operations. The lenticular and highly discontinuous nature of the sandstones and shales of the Menefee Formation, have led to the development of perched aquifer systems. Mine operations should not physically intercept these perched systems. Associated mechanical reaction to mining (floor heave, slabbing, or roof falls) may induce inflows from some of these perched aquifers. The existence of perched aquifers in the Mesaverde Group has been documented in the North Fork of the Gunnison River Valley. Usually, those perched aquifers are dewatered within 24 to 36 hours. It is quite possible that mine operations at Coal Gulch will intercept some perched aquifers during the life of the mine, or cause some perched aquifers to dewater into the mine. The overall impacts of dewatering these isolated pockets will be insignificant, so long as the water is properly stored and treated before being discharged into undisturbed Coal Gulch.