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