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-33- Calculations performed at the Mt. Gunnison mine, to estimate mine inflows, show that maximum inflows of 6.56 to 29.48 gpm, for confined and unconfined conditions respectively, may be expected in the next five years. This is exclusive of inflows from faults or from fractures in areas of shallow overburden. West Elk Coal Company used a model published by David McWorter in 1981 entitled Procedures for Predictive Analysis of Hydrologic Impacts of Surface Mining. Both confined and unconfined models were used. The model takes into account the size of the advancing workings, the rate of advancement, transmissivity, aquifer thickness, height of the piezometric surface above the coal seam, time in days, specific yield, and the storage coefficient. The values used in the calculations are conservative to average. The calculated values in the McWorter model are as follows. TIME t Q Q end of days confined coal unconfined coal gal/min gal/min 1982 365 2.48 10.42 1983 730 3.52 14.74 1984 1095 4.30 18.04 1985 1460 4.96 20_.84 1986 1825 5.56 23.30 1987 2190 6.08 25.54 1988 2555 6.56 27.58 1989 2920 4.02 29.48 The projected mine inflows that were estimated at Mt. Gunnison for the year 1983 were 3.76 gpm, and for 1984, 3.97 gpm. These values are close to the values calculated in the McWorter model for 1983, which calculated inflows of 3.52 gpm for confined conditions and 14.74 gpm for unconfined conditions. For 1984, 4.30 gpm for confined and 18.04 gpm for unconfined conditions were calculated. The actual mine inflow values, even with the flows from roof cracks and faults, are close to what would be expected for confined conditions. Additional inflows from the interception of a fault are possible and would cause a deviation from expected inflows. Radius of influence calculations done at Mt. Gunnison using the Sacob straight-line method project that the radius will extend to 0.4 miles in five (5) years. This value seems reasonable. It is projected by the applicant that most springs in the lease area derive their water from the Barren Member of the Mesa Verde Group, and further, that pining from the mine in the F-Seam should not affect aquifers in the zone more than 100 feet above the seam. Although the 100-foot estimation is somewhat generalized, this conclusion probably is realistic. Mining will impact springs issuing from the F-Seam and beds in the Barren Member immediately overlying it. Interference with springs will be most likely in areas of shallow overburden. In zones of substantial fracturing, springs issuing from beds more than 100 feet