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• 1.4 Groundwater Information <br />The data collected from the groundwater monitoring stations and laboratory results are <br />presented in section 4. <br />The sealing of all of the abandoned Somerset Mine portals precludes obtaining <br />underground water samples. Wells B-6 and H-10 aze used to monitor groundwater inflow and <br />quality in order to predict the extent of flooding in the underground workings since the mine was <br />closed in 1985. <br />H-10, a well in Hubbazd Creek Canyon, was monitored in April and October for field <br />pazameters. The full suite of groundwater pazameters was analyzed in October. After initially <br />rising to approximately elevation 6028, the water level in H-10 held steady for about two years <br />from 1987 to ] 989. Water levels then rose again to approximately elevation 6068 in 1992. The <br />water level has been in the range from 6067 feet to 6069 feet for the past five years. <br />B-6, a well in Beaz Creek Canyon, was monitored in April and October for field <br />pazameters. The full suite of groundwater pazameters was analyzed in October. Patterns of water <br />levels in B-6 aze much different than in H-10. After initially rising to elevation 6035, the water <br />level fell back to elevation 6014 in 1990. Water levels then recovered, with a slight dip at <br />elevation 6033 in 1992, to rise to elevation 6051 in 1993. The water level has been in the range <br />from 6038 feet to 6048 feet in 1994 and 1995, and the water level rose to 6054 feet in 1997. <br />• The Sanbom Creek Mine drill hole monitoring points SC-l, SC-2 and TC-1 are designed <br />to monitor the water level and quality of the water in the Rollins Sandstone which is 40 to 50 feet <br />below the B-Seam. SMC collected one yeaz's monitoring data during 1991 before any <br />substantial mining was performed in the B-Seam for the Sanbom Creek Mine for SC-1 and SC-2. <br />Monitoring data for TC-1 started in June of 1997. TC-1 water monitoring well is under pressure <br />so water elevation in the Rollins Sandstone can not be determined. <br />Monitoring of SC-1, SC-2 and TC-1 after mining is performed in the B-Seam should <br />confirm that the mining operation does not adversely affect the aquifer in the Rollins Sandstone. <br />The Rollins Sandstone is a confined aquifer as evidenced by recent water level measurements, <br />which are well above the top of the sandstone member. Water quality is poor, with high total <br />dissolved solids as sodium chloride. Inflow and recovery of the water level in the drill holes <br />indicates very low permeability and porosity of the sandstone. A significant drop in the water <br />level in SC-1, SC-2 or TC-1 would indicate that the mine may be having an impact on the <br />Rollins Sandstone. Although there has been some variability in the water levels, there does not <br />appear to be a trend either up or down. <br />Drill hole monitoring point SC-3 is designed to monitor the water level and quality of <br />water in the water bearing zone in the D-Seam. This water bearing zone is some 200-feet above <br />the coal seams to be mined. A significant drop in the water level in SC-3 would indicate that the <br />mine may be having an impact on this zone. Although there has been some variability in the <br />water levels, there does not appear to be a trend either up or down. <br />SC-1, SC-2, and SC-3 were monitored quarterly in March, June, September, and <br />December for field pazameters. The full suite of groundwater parameters was analyzed in June <br />• and December. There has not been a significant continued drop in the water levels in the past <br />five years since the wells were drilled. <br />9 <br />