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<br />Well SC-1 was completed in the Rollins Sandstone, which is located 40 to 50 feet below the B- <br />Seam. Monitoring data were historically collected from well SC-1 prior to any substantial <br />mining in the B-Seam of the Sanborn Creek Mine. The SC-1 well is up-gradient relative to the <br />Rollins Sandstone unit located under the footprint of the mining activities. <br />Water in the Rollins Sandstone is confined to limited localized zones that are fractured and/or <br />contained above the Rollins, as evidenced by water level measurements that are well above the <br />top of the sandstone member. Water quality is poor, with high total dissolved solids as sodium <br />chloride. Inflow and recovery of the water level in the drill holes indicates very low <br />permeability and porosity of the sandstone. There has been some variability in the water levels <br />measured in well SC-1 but there has been no apparent trend or indication of impact. No <br />significant difference in the 2003 monitoring results from baseline or historical measurements <br />was noted in well SC-1. <br />The limited water quantity and poor water quality suggests there is limited transmissivity <br />between the North Fork of the Gunnison River alluvium through the Rollins sandstone down- <br />gradient towards the area associated with the Sanborn Creek Mine. <br />SC-3 Well - B-Seam -Sanborn Creek Mine <br />• Monitor well SC-3 is located east of the Sanborn Creek mine portal area along the entrance to <br />the pre-existing ranch road to Coal Gulch. <br />Monitoring well SC-3 was completed in the B Seam coal. Monitoring data were collected from <br />well SC-3 prior to any substantial mining in the B-Seam of the Sanborn Creek Mine. The SC-3 <br />well is up-gradient relative to the B seam underground mining activities but down-gradient from <br />the North Fork of the Gunnison River <br />The plastic pipe casing is squeezed at the 20 foot level making it difficult to lower a bailer. Once <br />a smaller diameter bailer was obtained very minimal water was available and a sample could not <br />be obtained. During the fall sampling period the well lacked the requisite water volume to fill up <br />the three required sample bottles. The lack of water in the well during a drought period and the <br />poor water quality suggests there is little transmissivity and connection between the North Fork <br />of the Gunnison River and the B coal seam at this particular vicinity of the mine. <br />As the of SC-1 and SC-3 wells serve to monitor only the Rollins sandstone and B-seam coal <br />respectively up-gradient of the Sanbom creek mining area, their utility towards the monitoring <br />of the Sanbom creek mine itself appears somewhat limited. <br />• <br />t2 <br />