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• 1994 Annual Hydrologic Report <br />Page 6 <br />and 20 were affected to a large degree by the pumping schedules. <br />The flow at 20 represents a maximum pump discharge and the flow at <br />5 ranged from 96 to 189 but averaged 163 with several readings. <br />Flow from dewatering holes drilled into the 3 West, 8 West and 9 <br />West panels are represented by locations 26, 6 and 15 respectively. <br />Each of these panels represents approximately 25 acres of mining. <br />The sump on the No.3 South Mains continued to be used to supply <br />water to the mining sections and to provide water for dust control <br />and firefighting. This sump is primarily fed by pumping from <br />location 30. The flow at locations 27 was covered up by roadway <br />work and may have surfaced other places like location 28. In most <br />cases the conductivity continued to be similar to previous <br />readings. At location 6 in 1993, conductivity increased due to it <br />being in contact with recently exposed rock from the panel caving <br />but has dropped off since then, similar to the pattern seen at <br />location 15 in last year's report. Conductivity at locations 3, <br />15, 25 and 31 may have increased due to a decrease in flow <br />corresponding to a concentration of salts through infiltration or <br />evaporation. The conductivity of flows along the 3 South Mains <br />• flow path through 20, 14, 5 and 10 was lower this Year due to <br />flushing of minerals along the path. The mass average pH and <br />conductivity for these inflows was 8.4 and 874 umhos/cm <br />respectively. Using the average pH, conductivity and discharge for <br />001 and 002, the mass average pH and conductivity discharged during <br />the year was calculated to be 7.4 and 2766 umhos/cm. Table M94-3 <br />was prepared to estimate the total inflows and discharges from the <br />Roadside South Portal but does not include the water consumed for <br />mining purposes as discussed in the Consumptive Use section of this <br />report. For the inflow calculation, an attempt was made to account <br />for water level changes in the old portions of the mine. Negative <br />values of "water level" flow represent periods when the water level <br />was decreasing as a result of discharge being greater than the <br />inflow. The calculated inflows for September were 235.1 gpm which <br />is close to the 221.$ gpm measured. <br />Larger changes than normal occurred at the Roadside North Portal <br />this Year. Location 1 is from underdrains in the portal decline <br />and has an alluvial source. The lower conductivity is not unusual <br />for the site and may be a delayed affect of higher river flows in <br />1993. The lower flow may reflect the difficulty of measurement at <br />this site. Location 7 is no longer accessible due to the area <br />being sealed. Work was done in the mine during the summer to <br />better collect water and get it to the sump. This work resulted in <br />lower flows at locations 4 and 5 and higher flows at location 6. <br />Work in the flow paths of locations 4 and 5 may have increased the <br />• conductivity. Location 8 represents water in an old portion of the <br />mine. Dewatering of this sealed area is random and not measured. <br />Flow at this location is estimated by subtracting the measured <br />inflows from the average September discharges. The mass average pH <br />