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Rule 2.05 • Flow rates from RSP-4 have consistently been estimated in the 2 to 6 gpm range and also appear to reflex annual snowpack conditions. Water quality is somewhat poorer than in RSP-3 with post mining TDS levels ranging from about 2500 to 3400 mg/I. Like RSP-3, dominant constituents are sulfate, calcium, sodium and bicarbonate, but with proportionately considerably higher sodium and magnesium levels. The pH is somewhat lower than in RSP-3, but apparently stable, with a range of 6.6 to 7.8. No easily discernible trends in water quality have been observed. Somewhat elevated levels of iron, aluminum and manganese were reported for samples taken in 1988 and 1989, but there do not appear to be any increasing trends for these parameters. Other spoil springs have been sampled when they produced sufficient flow to allow sample collection but have only been analyzed for the field parameters of pH, conductivity, and temperature. Flows of the seeps/springs have also been estimated during the annual seep and spring inventories. Flows in RSP-1 and RSP-2 have been consistently estimated at less than 1 or 2 gpm. RSP-5 and RSP-6 have been essentially dry since reclamation was completed in 1987. Water quality in the two wells regularly sampled, HGl and HG2, has not shown any significant changes since monitoring in these wells began in 1987. Both wells were completed as replacement monitor wells in response to MLRD concerns about the adequacy of previous monitor wells, az described in Section 4.05.13, Surface and Ground Water Monitoring. Evaluation of water quality data from 1994 well samplings indicate no significant changes from previous years or problems with water quality parameters. Both wells indicate generally good but "hard" water quality. TDS levels in HGl have varied from 656 to 976 mg/l with a mean • value of 814 mg/1. TDS levels in HG2 are slightly higher with a range of 732 to 1064 mg/1 and a mean of 947 mg/I. The pH values are also very stmtlar, and consistent, for the two wells with respective ranges for HG-1 of 6.9 to 8.0 and ranges of 6.2 to 8.0 for HG2. Primary TDS constituents in both wells are sulfate, bicarbonate, calcium, magnesium and sodium. No obvious water quality trends are evident in either well. The only concern with heavy metals and trace constituents has been occasional high iron levels in well HG2. It is suspected that elevated iron levels may be associated with some type of iron bacteria although the source could also be a an oxidation/reduction contact in or near the well. Initial water production from the well during sampling is sometimes very discolored with iron staining but prolonged well purging prior to sample collection has been successful in clearing the water and substantially elimina[ing discoloration. The relatively rapid clearing of water pumped from the well suggests that the high iron occurrences are very localized and confined to either the well bore or immediate well vicinity. Water levels within the coal zone aquifer have shown considerable fluctuations since completion of reclamation, az indicated by well HG2. Water levels steadily declined about 20 feet from June 1988 through September 1990, then rebounded sharply in June 1991. From August 1993 through the 1994 readings, a steady decrease in water levels has been observed. The magnitude and relative speed with which water levels change in HG-2 suggest that the water table (from approximately SO to 100 deep) is fairly responsive to seasonal ground water recharge events. In comparison, water levels in well HGl have shown relatively minor fluctuations but an overall pattern similar to HG2. Well UC-1, which waz repor[edly completed in the upper coal zone and is monitored for water level only, has shown essentially no change in water levels from 1987 through 1994. H \eJJ\PERMn\RULEI-0S.HG 11/1N9s I.JOpm wrsv~m~ 2,05-16 Revised - 11/28/95