2010-03-15_REPORT - C1981022 (2)

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• where that monitor well indicates a reestablishment of a water level in the old somerset Mine B seam workings. Once a year, samples of water are taken of water transferred to D213 and 132132 and summarized below. The access to the pumps leading to D2132 were sealed before samples were taken. There were no unique conditions in the mine that would suggest the samples, had they been available, would not have been comparable to previously obtained samples. No issues have been encountered with respect to the analytical results. D2B D2B2 Date H TSS H TSS October 15, 2009 8.44 17 Not available Not available December 31, 2008 8.69 38 mg/1 Not available Not available December 31, 2007 8.72 17 m g/1 8.49 14 mg/1 June 13, 2006 8.58 12 m 1 8.15 39 mg/1 June 6, 2005 8.57 lo m 1 NA NA December 28, 2004 8.53 6 m 1 NA NA SC-1 Well -Rollins Sandstone • Monitor well SC-1 is located just east of the reclaimed Sanborn Creek mine portal area. Well SC-1 was completed in the Rollins Sandstone, which is located 40 to 50 feet below the 13- Seam. Monitoring data were historically collected from well SC-1 prior to any substantial mining in the B-Seam of the Sanborn Creek Mine. The SC-1 well is located up-gradient relative to the Rollins Sandstone unit which is located stratigraphically under the footprint of the mining activities. Water in the Rollins Sandstone is confined to limited localized zones that are fractured and/or contained above the Rollins, as evidenced by water level measurements that are well above the top of the sandstone member. Water quality is poor, with high total dissolved solids as sodium chloride. Inflow and recovery of the water level in the drill holes indicates very low permeability and porosity of the sandstone. There has been some variability in the water levels measured in well SC-1 but there has been no apparent trend or indication of impact. No significant difference in the 2009 monitoring results from baseline or historical measurements was noted in well SC-1. The limited water quantity and poor water quality suggests there is limited transmissivity between the North Fork of the Gunnison River alluvium through the Rollins sandstone down- gradient towards the area associated with the Sanborn Creek Mine. SC-3 Well - B-Seam Coal - Sanborn Creek Mine • Monitor well SC-3 is located east of the Sanborn Creek reclaimed mine portal area along the entrance to the pre-existing ranch road to Coal Gulch. 15