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operations in the No. 5 Mine expand and eventually extend to the No. 6 Mine is uncertain. A forecast of generally increasing inflow to the mines as a result of their future expansion is made by the operator who projects a total inflow ranging between 860 qpm and 1070 gpm by the fifth permit year. Current inflow, estimated from studies in the mine and indicated by records of mine discharge is in the 600 to 800 gpm range. The impacts of past inflow on the quantities of water in the major aquifers has been limited to the Trout Creek sandstone and, possibly, the Middle sandstone. No impacts have been seen on aquifers above the level of the Middle sandstone. Impact on the Trout Creek, which lies below the mining level, occurs because of the faulting which connects the mine workings and the aquifer. Since the areas of the No. 5 and No. 6 mining during the first permit term is unfaulted, it is unlikely that the increase in future inflow will come from the Trout Creek aquifer. The source, then, of this additional inflow is likely to be the sedimentary section most closely associated to the mining operation, a section that inc]udes the Middle sandstone. Some part of this future increase in inflow into the No. 5 and No. 6 Mines may specifically relate to the effects of subsidence on the sediments and aquifers that overlie the long walling to occur in the Eagle Mines. According to the applicant, maximum caving and fracturing of the section affected by the subsidence will extend no more than five meters above the mining level. Above this zone, the sedimentary section will under go a measure of subsidence, some possible separation of beds, and a degree of fracturing. During the first five permit years, the subsidence will be confined to or will be near the outcrop areas of the Middle and Twentymile sandstones in the southern Williams Fork Mountains. At present, the portion of the No. 5 Mine underlying this area is one of the driest parts of the mining operation. This is possibly due to the fact that the mining is taking place so close to areas of outcrop and recharge of the coals and their hydrologically related section, There is, however, 500 feet of static head currently developed in the tAiddle sandstone just beyond the predicted northern limits of the area to subside during the first permit term. These artesian conditions in the aquifer undoubtedly extend Some distance south at the monitoring well into the area to be affected. If fracturing of the section between the level of mining and the Middle sandstone in this area ultimately does establish a significantly greater degree of communication with the mine, the area of confined water in the aouifer will be reduced. An impact on the quantity of water in the aquifer can be expected; water levels in the Middle sandstone should dec]ine over a relatively large area. The Middle sandstone, however, does not supply water for beneficial use in the permit or adjacent areas; the practical effect of this adverse impact on local water supplies is minimal. The Twentymile sandstone is one of the more important bedrock aquifers in the area with much greater extent and use than the Middle sandstone. Water wells for the Trapper Mine currently produce from the Twentymile sandstone; the mine supply well for the abandoned Eagle No. 9 Mine also produced from this aquifer at one time. The Eagle No. 5 mining, located approximately 500 feet below the Twentymile Sandstone, has had no recorded significant impact on the quantity of water in this aouifer. Since the proposed No. 6 Mine will underlie the No. 5 Mine, at least in the first five permit years, little future impact of operations in these mines would be expected, if room and pillar mining methods were employed. Lortgwall methods, however, will be used in the future in both the No. 5 and No. 6 Mines and will even coincide in an area approximately one-half square mile in size located in Section 5, TSN, R91W. As previously -31-