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• Sanborn Creek Mine 1995 Annual Hydrologic Report parameters was analyzed in October. After initially rising to approximately elevation 6028, the water level in H-10 held steady for about two years from 1987 to 1989. Water levels then rose again to approximately elevation 6068 in 1992. The water level has been in the range from 6067 feet to 6069 feet for the past four years. B-6, a well in Bear Creek Canyon, was monitored in April and October for field parameters. The full suite of groundwater parameters was analyzed in October. Patterns of water levels in B- 6 are much different than in H-10. After initially rising to elevation 6035, the water level fell back to elevation 6014 in 1990. Water levels then recovered, with a slight dip at elevation 6033 in 1992, to rise to elevation 6051 in 1993. The water level has been in the range from 6038 feet to 6048 feet for the past two years, and 6031 feet to 6051 feet for the past four years. The Sanborn Creek Mine drill hole monitoring points SC-1 and SC-2 are designed to monitor the water level and quality of the water in the Rollins Sandstone which is 40 to 50 feet below the B-Seam. SMC collected one year's monitoring data during 1991 before any substantial mining was performed in the B-Seam for the Sanborn Creek Mine. Monitoring of SC-1 and SC-2 after mining is performed in the B-Seam should confirm that the mining operation does not adversely affect the aquifer in the Rollins Sandstone. • The Rollins Sandstone is a confined aquifer as evidenced by recent water level measurements, which 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. A significant drop in the water level in SC-1 or SC-2 would indicate that the mine may be having an impact on the Rollins Sandstone. Although there has been some variability in the water levels, there does not appear to be a trend either up or down. Drill hole monitoring point SC-3 is designed to monitor the water level and quality of water in the water bearing zone in the D-Seam. This water bearing zone is some 200-feet above the coal seams to be mined. A significant drop in the water level in SC-3 would indicate that the mine may be having an impact on this zone. Although there has been some variability in the water levels, there does not appear to be a trend either up or down. SC-1, SC-2, and SC-3 were monitored quarterly in March, June, September, and December for field parameters. The full suite of groundwater parameters was analyzed in June and December. There has not been a significant continued drop in the water levels in the past five years since the wells were drilled. 9 •