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Rule 2.05 <br />• Flow rates from RSP-4 have consistently been estimated in the 2 to 6 gpm range and also appear to reflect <br />annual snowpack conditions. Water quality is somewhat poorer than in RSP-3 with post mining TDS <br />levels ranging from about 2500 to 3400 mg/1. Like RSP-3, dominant constituents aze sulfate, calcium, <br />sodium and bicazbonate, but with proportionately considerably higher sodium and magnesium levels. The <br />pH is somewhat lower than in RSP-3, but apparently stable, with a range of G.6 to 7.8. No easily <br />discernible trends in watu quality have been observed. Somewhat elevated levels of iron, aluminum and <br />manganese were reported for samples taken in 1988 and 1989, but there do not appeaz to be any <br />increasing trends for these parameters. <br />Other spoil springs have been sampled when they produced sufficient flow to allow sample collection but <br />have only been analyzed for the field parameters of pH, conductivity, and temperature. Flows of the <br />seeps/springs have also been estimated during the annual seep and spring inventories. Flows in RSP-1 <br />and RSP-2 have been consistently estimated at less than 1 or 2 gpm. RSP-5 and RSP-6 have been <br />essentially dry since reclamation was completed in 1987. <br />Water quality in the two wells regulazly sampled, HG-1 and HG-2, has not shown any significant changes <br />since monitoring in these wells began in 1987. Both wells were completed as replacement monitor wells <br />in response to MLRD concerns about the adequary of previous monitor wells, as described in Section <br />4.05.13, Surface and Ground Water Monitoring. <br />Evaluation of water quality data from 1994 well samplings indicate no significant changes from previous <br />years or problems with water quality parameters. Both wells indicate generally good but "hazd" water <br />quality. TDS levels in HG-1 have varied from 656 to 976 mg/1 with a mean value of 814 mg/1. TDS <br />levels in HG-2 aze slightly higher with a range of 732 to 1064 mg/1 and a mean of 947 mg/1. The pH <br />values aze also very similaz, and consistent, for the two wells with respective ranges for HG-1 of 6.9 to 8.0 <br />• and ranges of G.2 to 8.0 for HG-2. Primary TDS constments in both wells are sulfate, bicarbonate, <br />calcium, magnesium and sodium. No obvious water quality [tends aze evident in either well. <br />The only concern with heavy metals and trace constituents has been occasional high iron levels in well <br />HG-2. It is suspected that elevated uon levels maybe associated with some type of iron bacteria although <br />the source could also be a an oxidation/reduction contact in or near the well. Initial water production <br />from the well doting sampling is sometimes very discolored with iron staining but prolonged well purging <br />prior to sample collection has been successful in clearing the water and substantially eliminating <br />discoloration. The relatively rapid deazing of water pumped from the well suggests that the high iron <br />occurrences are very localized and confined to either the well bore or immediate well vicinity. <br />Water levels within the coal zone aquifer have shown considerable fluctuations since completion of <br />reclamation, as indicated by well HG-2. Water levels steadily declined about 20 feet from )one 1988 <br />through September 1990, then rebounded sharply in June 1991. From August 1993 through the 1994 <br />readings, a steady decrease in water levels has been observed. The magnitude and relative speed with <br />which water levels change in HG-2 suggest that the water table (from approximately 50 to 100 deep) is <br />fairly responsive to seasonal ground water rechazge events. In comparison, water levels in well HG-1 have <br />shown relatively minor fluctuations but an overall pattern sitnilaz to HG-2. <br />Well UC-1, which was reportedly completed in the upper coal zone and is monitored for water level only, <br />has shown essentially no change in water levels from 1987 through 1994. <br />The Phase II/Phase III hydrologic impact assessment also evaluated groundwater and concluded that <br />there was not advuse impact to aquifers in the azea. HGCC abandoned the groundwater monitoring wells <br />in October 1998 pet Division of Water Resource guidelines. The abandonment reports were included in <br />the 1998 Annual Hydrology Report. <br />2.05-16 Revised - 6/01 <br />