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June 6, 2005 <br />8.57 <br />10 m /l <br />NA <br />NA <br />December 28, 2004 <br />8.53 <br />1 6 m /l <br />NA <br />NA <br />SC -1 Well — Rollins Sandstone <br />Monitor well SC -1 is located just east of the reclaimed Sanborn Creek mine portal area. <br />Well SC -1 was completed in the Rollins Sandstone, which is located 40 to 50 feet below the 13 - <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 located up -gradient relative <br />to the Rollins Sandstone unit which is located stratigraphically under the footprint of the mining <br />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 past water level measurements that are well above <br />the top of the sandstone member. Water quality is poor, with high total dissolved solids as <br />sodium chloride. Inflow and recovery of the water level in the drill holes indicates very low <br />permeability and porosity of the sandstone. The 2012 sampling indicated a substantial drop in <br />dissolved solids, chlorides, etc. These parameters appeared to return to "normal" in 2013. A <br />review of the long term water level appears to show a continuous drop in water level elevation, <br />suggesting low transmissivity of water into the sandstone from the up gradient river. In 2014 the <br />water level was so low there was barely enough to trip the sounder recording the water level. <br />During 2016, there was insufficient water for bottled samples. <br />Generally, the limited water quantity and poor water quality suggests there is limited <br />transmissivity between the North Fork of the Gunnison River alluvium through the Rollins <br />sandstone down -gradient towards the area associated with the Sanborn Creek Mine. <br />SC -3 Well - B -Seam Coal — Sanborn Creek Mine <br />Monitor well SC -3 is located east of the Sanborn Creek reclaimed mine portal area along the <br />entrance to the pre-existing ranch road to Coal Gulch. <br />Monitoring well SC -3 was completed into the B Seam coal. Monitoring data were collected <br />from well SC -3 prior to any substantial mining in the B -Seam of the Sanborn Creek Mine. The <br />SC -3 well is up -gradient relative to the B seam underground mining activities but down -gradient <br />from 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. <br />Using a smaller diameter bailer we have found very minimal water available in the well. In fact <br />there are times when the initial bailing of the well to remove one volume effectively drains the <br />available water. The lack of water in the well and the poor water quality suggests there is little <br />transmissivity and connection between the North Fork of the Gunnison River and the B seam <br />coal at this particular vicinity of the mine. The elevated 2012 levels of zinc and iron appeared to <br />return to "normal" but sulfate seemed to remain elevated. Perhaps the lack of water in the well is <br />skewing the results. Overall depth appears to be "normal". <br />18 <br />