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At Hay Gulch, approximately the Menefee Formation/Point system. If this strata may be affected by mining, The "A" coal seam and the upper from this source due to mini Surface Water 5 miles west of Coal Gulch, data indicates that Lookout Sandstone contact may be an aquifer indeed be considered a major aquifer, it would not relatively impermeable strata between the Point Lookout is thick enough to preclude inflow induced hydrostatic pressures. At the proposed mine site, the natural Coal Gulch channel has been destroyed by previous mining operations. Currently, the stream is diverted into an artificial channel which skirts the west and south edges of the mine facilities area and crosses under Highway 160 just below the sediment pond discharge point. The probable hydrologic consequences of mining to the surface system include: 1. De-watering of colluvial slumps and ephemeral drainages by subsidence related fracturing; and 2. The addition of abandoned portal discharges to Coal Gulch flow. Subsidence fractures could intercept ephemeral drainages which contain colluvial slumps. These drainages normally flow during snowmelt and in response to rainstorms. The slumps, as discussed in the surface water description, provide base flow to the streams. If subsidence fractures were to intercept the ephemeral drainages and the base of the slumps, water would be re-directed into the mine. Whatever volume of water is directed into the mine would discharge at the abandoned portals. The most significant threat to the surface flow at Coal Gulch will be the inflow of water from the abandoned mine. The water which is discharged from abandoned portals in the Coal Gulch area is typically low in pH, and high in manganese, sulfate, iron and total dissolved solids. Water from the abandoned Coal Gulch Mine is expected to exhibit similar characteristics. Locally, the addition of elevated levels of these constituents will contribute to diminished water quality. Dependent upon the amount of water added to the stream from the abandoned portal (a predicted maximum of 25 gal/min) and the volume of water flowing in the gulch (predicted maximum of 10 cfs in a normal water year), the discharge waters will rapidly be diluted. In lower Coal Gulch, and most certainly in Lightner Creek and the Animas River, no effects of the portal discharge will be observable. During mining, the sediment pond and water treatment facilities will ensure that no portal discharges will reach the stream until the water meets NPDES effluent standards. The Coal Gulch Mine has been designed to minimize damage to the prevailing hydrologic balance. This section is in compliance with the regulations.