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-42- percent of the stream flow for the Mt. Gunnison life-of-mine area during the dry part of the year. In a worst-case scenario, where all of the springs dry up, 6.2 percent of the low flow runoff could be lost. In reality, it is probable that not all the springs would be affected and, therefore, reduction of surface flow would be less than the worst-case scenario. The accuracy of WECC's predictions, and significance of the results will be determined if WECC ever decided to request approval to mine these area. A loss of spring flow may not entirely be lost to the hydrologic system. It may temporarily become a part of the ground water system and eventually reemerge at the surface. It is difficult to predict where this water may reemerge. It could reemerge downstream in the same drainage (the Minnesota Creek system), or it could reemerge along the North Fork of the Gunnison after flowing through the mine workings. In the latter case, the impact upon water users located along Minnesota Creek is potentially the greatest. In either case, flow below the confluence of Minnesota Creek and the North Fork of the Gunnison should not be affected. Withdrawal of Water from the North Fork of the Gunnison for Mine Use Stream flows may also be depleted through the withdrawal of water from the stream or the alluvium of the stream for use in the mining operations. The Terror Creek Coal Yard withdraws water from two sources. Water for dust suppression is supplied by senior water rights from the Deertrail Ditch. The ditch withdraws water from Hubbard Creek. Use averages 5,000 gallons per day. Previously, this water was used to irrigate orchards where the loadout is now situated. A domestic well which supplies about 450 gallons per day is used for domestic use at the loadout office. Since the company has just changed water use from agriculture to domestic, there is little net depletion to the North Fork River system. Bear Coal Company will utilize 1.15 acre-feet per year of domestic water from the Somerset Domestic Waterworks as drinking water. Water used for dust suppression on roads and for wash down of the mine shop and equipment is pumped from a shallow well located in the alluvium next to the North Fork at the rate of 5.3 ac. ft. per year. Within the mine, the water will be used to cool equipment and for dust suppression. The total estimated consumption of water which is tributary to the North Fork of the Gunnison River will be 5.5 acre-feet per year. This consumption represents 0.001% of the mean annual yield in the North Fork. Additional minor amounts of water will be consumed through evaporation from the sediment ponds at the mines. The Blue Ribbon Mine consumes about 16,010 gallons of water per day (11.12 gpm). This water is pumped from a well completed in the alluvium of Hubbard Creek. This alluvial water is tributary to the flow of water in Hubbard Creek. The water consumption consists of 1,050 gpd for sanitary and domestic use, 9,600 gpd for water absorbed on the coal from the mine, and 5,360 gpd for dust control and equipment wash down. The total depletion of water tributary to the North Fork of the Gunnison for a 250-day work year will be 12.28 acre-feet per year. This is 0.003% of the mean annual yield in the North Fork.