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No significant depletion of ground water in the B-Seam is expected to result from mining at Bear No. 3. Small amounts of water enter the mine from walls, roof and floor in recently mined areas. These inflows cease one to two weeks after the area is mined. 11te small inflows and the lack of any reconled mine discharges indicates that no significant impact to ground water resources will result from mining in the B-Seam. However, due to the increase in B-Seam mining area that will result from approval of Permit Revision No. 2, it is now anticipated that infiltration into the subsided B-Seam may occur in volumes significant enough to cause discharge into the North Fork of the Gunnision River via We B-Seam contact. If this occurs, the water is likely to be of degraded quality, especially with respect to dissolved solids. It is not believed that this will have a significant overall impact on water quality in the North Fork River and as a precautionary measure to ensure this pn~iction is borne out, the Division is requiring the operator to install a monitoring well downdip from the workings and into the B-Seam. T7tis action is being done via Stipulation No. 34, which is listed below. .THE PERMITTEE VVII.L INSTALL A GROUND WATER MONITORING WELL WN-DIP FROM THE MINE WORKINGS AND IIVTO THE B-SEAM (BETWEEN THE URTH NORTH MAINS AND THL NORTH FORK OF THE GUNNISION RIVER) THE PURPOSES OF MONITORING THE POTENTIAL EFFECTS OF MINING ON THE B-SEAM AQUIFER. THE FINAL LOCATION AND TA~IING OF INSTALLATION WQ.L BE MUTUALLY AGREED UPON BY THE OPERATOR AND THE DIVISION AFTER FURTHER FIELD INVESTIGATION, BUT INSTALLATION SHALL OCCUR NO LATER THAN AUGUST 31, 1995. MONITORING SHALL OCCUR SEMI-ANNUALLY FOR FIELD PARAMETERS AND WATER LEVEL AND ONE FULL SUITE SAMPLE SHALL BE TAKEN ANNUALLY IN THE FALL. T'I~ TEST PARAMETERS FOR THE FULL SUTTE SAMPLE SHALL BE THE SAME AS REQUIItED FOR THE ALLUVIAL WELLS (TABLE 4F) PLUS MAGNESIUM AND SAR. Degradation of water quality in the alluvial aquifer below the Bear No. 3 facilities area is not anticipated. T7ie North Fork of the Gunnison River is hydrologically connected to the alluvial material. Approximately 3,800 acre-feet of water annually pass through the facilities area alluvial body. Precipitation and snowmelt on the Bear No. 3 facilities area will infiltrate the alluvial material. The annual contribution to the alluvial material, assuming all incident precipitation and snowmelt enters the alluvium, is 15.42 acre-feet. This infiltration is 0.4 percent of the average flow through the alluvium. The dilution ratio of 246:1 indicates the large dilution capability of the alluvial aquifer. The actual amount of water infiltrating the Bear No. 3 21