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• 1997 Annual Hydrologic Report Page 7 r~ L_J I~ Mine Water The annual mine inflows study for this Year was taken the end of September 1997. This study is being made a part of the AHR. The results of the study are given on data pages MA-16 thru -18 and MB-12. A summary of past conductivity and flows from the monitoring locations are given on Tables M97-1 thru 5. Inflow monitoring locations are shown on the 1997 Mine Inflows Map. As usual, there are many differences in the monitoring results at the Roadside South Portal. These differences are primarily the result of changes in mining locations; differences in water routing, piping and pumping patterns; and general difficulties involved with monitoring underground. The big change this Year was the large increase in flow at the south mains sump location 5. Monitoring at locations 24, 25, and 27 thru 31 was discontinued in 1996 due to sealing of the south end of the No. 2 South Mains. Flow from these locations is piped from these seals and is now monitored as new location 34. Flows from sealed panels at locations 26, 15 and 6 dried up as well as location 16. The reduction inflow from these sites may have corresponded to increased inflows in the 6th East Panel. This panel was completed and sealed in June of 1996 and inflows into the panel were not accessible. The "total inflows" in the last column of Table M97-3 shows increasing inflows for the Year Conductivity at location 23 was higher than the corresponding sources from previous studies probably because the flow was only a trickle. This is typical of water setting in a sealed area prior to discharge. The mass average pH and conductivity for the inflows was 8.3 and 1382 umhos/cm respectively. Using the average pH, conductivity and discharge for 001 and 002, the mass average pH and conductivity discharged during the Year was calculated to be 7.5 and 2064 umhos/cm. Table M97-3 was prepared to estimate the total inflows and discharges from the Roadside South Portal but does not include the water consumed for mining purposes as discussed in the Consumptive Use section of this report. For the inflow calculation, an attempt was made to account for water level changes in the old portions of the mine. Negative values of "water level" flow represent periods when the water level was decreasing as a result of discharge being greater than the inflow. The calculated inflows for September were 237.3 gpm which is slightly less than the 258.1 gpm measured.