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X23- Paonia Reservoir. This reservoir is located approximately 6 miles upstream of the alluvial valley floor. Total surface disturbance is limited to 19 acres at the Bear No. 1 and No. 2 facilities area and 8 acres at the proposed Bear No. 3 mine. Drainage from the disturbed areas will be treated in sediment ponds and discharges from these ponds will have to meet the effluent limitations of Rule 4.05. Ground water supplied from bedrock strata is minimal. No major aquifers have been identified in either the coal seam or the overburden. Springs in the area are associated with Zen ticular sandstones, local faulting and fracturing, and landslides. No springs or seeps have been identified in the area to be mined by Bear Coal Company. Surface operations would have an insignificant impact on the quantity of flow in the North Fork of the Gunnison. Mining operations coould require approximately 5.5 acre- feet of water per year, Zess than 0.030 of the mean annual flow in the North Fork of the Gunnison River. Surface disturbance in the alluvium adjacent to the river will be Limited to topsoil removal and foundation work. Surface facilities will include office and shop buildings, a 10,000 ton open coal storage stockpile, access and haul roads, diversions and a sediment pond. All surface drainage from disturbed areas will be routed to the sedimentation pond where suspended sediments are allowed to settle out (see Map IO of the Bear No. 3 application). There is a potential for a slight increase in total dissolved solids (TDS) concentrations in the North Fork alluvial ground water as a result of percolation through coal stockpiles and the sediment pond. The percolation could occur during snowmelt and rainfall. The potential for this water quality degradation is considered insignificant for the following reasons: First, the amount of water which percolates into the alluvium is small since the slope of the coal stockpile will favor runoff and since the sediment pond will be dewatered after effluent limitations have been reached. This small amount of affected alluvial ground water will be rapidly diluted by the existing ground water in the system. Estimates made by the applicant, based on a pump test performed on an alluvial well at the site, indicate average flag rates of over 2 million gallons per day in winter months (see "Alluvial Ground Water Hydrology of the North Fork of the Gunnison River - Bear No. 3 Operation" contained in the Bear No. 3 revision application). Second, the identified alluvial valley floor is located more than a mile downstream from the surface facilities area of the Bear mine. This should be a sufficient distance for the dilution to acceptable ZeveZs of any effected alluvial ground water. Third, the potential impact to alluvial water quality will only be short-term. Once mining operations are completed, the coal stockpile and sediment pond at the No. 3 mine will be reclaimed and the alluvial ground water quality will quickly recover. Surface facilities at the Bear No. 1 and No. 2 portals will be removed, and the area regraded, topsoiled and seeded by the fall of 1982.