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•~ C J Hcdralo~ic ,rlorutariny ,acuriries times per year. Monitored parameters included water leveh pH. conductivity, temperature, total dissohed solids. total suspended solids, total iron, and rotal manga- nese. Results of the sampling efforts arc summa- rized in Appendix H. Hydrographs depicting water levels from 1973 to the present have been included as Appendix I. Minimum and maximum c~mpari- sons are presented in Appendix E. wells was either nonexistent or insufficient fur Water level and sampling records (or water vear 1992 were complete for [en wells. Water in Il "F" Seam No new minine occurred in the F seam and no new inflows wcre uhscrved. The I West. I East. and 1 Northwest Submains were sealed off at the Southwest and South Main Intakes and nu Curther monitoring of these areas can be conducted. Existing intlows in the Main Intakes wcre similar to those shown last year. Rcler to the map entitled "F Seam Mine Map - Hydrologic Condi- tions - Water Year 1991" in the 1991 Annual Hydrology Report. sampling. Neither water level or quality samples "B" Seam were acquired from the lost wells SOM-323-H2 and SOM-38-H3. ~ -~ `` DVS ~a~i1 L WfUVt~.CZ~'~ Small quamitites of water (<1 GPM) were Mine Water Monitoring V encountered during development mining in 1991. Because dripping and water inflow generally subsided within 2d hours, the water appears to ba Mine water inflows in areas being actively mined contained within fractures and found in association were mapped during water year 1992. Areas of with roofjoints, minor faults, ur rock spars. Areas previous mine inflows were monitored by occasion- of damp top persisted locally alone the more al visits. Exhibit 3 shows locations of intlows and pronounced fracture trends. estimated amounts of mine intlows in the "B" seam. Areas of standing water are also shown. During 1992, samples of mine discharges were taken from the MB-t, MB-2, and MB-6 sediment ponds. They were tested for pH, electrical c~nduc- tivity, total suspended solids, total dissolved solids, and total iron. Results of the analyses are shown on Table 5. The higher levels of conductivity. TDS, and iron are probably due to discharges of the more mineralized water and refuse associated with the B seam. However, the overall quality of water sampled was good and posed no problem for direct discharge to a stream or other surface feature. The mine water balance, based on actual and estimated flows, is shown in Table 6. The quantity of water discharged or pumped from the mine was approximately 37 acre feet. Water unaccounted for is lost through seepage and evaporation into the ventilating air. Both of these losses can be large, depending on conditions. Water inflows wcre greatest alone the more highly fractured zones. Initial water inflows were estimat- ed as high as 20 gpm. After fractures were de- watered.~inllows dropped suhstantialh. No loca- tions produced sustained nuws of water (Exhibit 3). Nu seasonal variation in (lows wxs ohsen•ed. 5