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• 1991 ANNUAL HYDROLOGIC REPORT PAGE 2 According to the local irrigation office many of the area springs have dried up during the preceding three years. The flows in Springs 1 & 3 this year were lower than average, about one half, which is to be expected. The revised hydrologic monitoring program expanded the sampling of springs 1 & 3 to flow and conductivity twice each year because the quality of the springs may be impacted by water which may seep into the alluvium from the old mine workings. Both springs had a conductivity which was relatively close to their respective historic averages. The conductivity of the springs will probably show some increase in the future if the flows in the springs continue to decrease. The revised hydrologic monitoring program provides for addi- tional monitoring to determine if run-off from the mine site has any impact on the water quality in the Carbon Ditch. SP-D is the upstream monitoring point and SP=DA is the new downstream monitoring point on the Carbon Ditch. SP-D is located on the Carbon Ditch at a point that would not be impacted by surface run-off from the mine site. SP-DA is located downstream on the Carbon Ditch at a point that could be impacted by surface run-off from the mine site. Both points are monitored during May and September for field parameters and total suspended solids, (TSS). In May the TSS for SP-D and SP-DA was 2185 and 2765 respectively which indicates some degradation of the quality of flow. One reason for the apparent degradation could be the high flow which may have further eroded the ditch banks between the two monitor- ing points. At the time of monitoring, there was no run-off oc- curring from the mine site so it is unlikely that the mine site caused the 26% increase in TSS between the upstream and downstream monitoring points. Monitoring during September did not show any degradation of quality from SP-D to SP-DA. The sediment pond did not discharge during the year. The pond did not have any water in it at all during the year. GROUND WATER Table G-91 shows the ground water monitoring results for this water year compared to the averages of previous monitoring results for the same months. The alluvial piezometers near the sediment pond are the only ground water that is currently being monitored. The alluvial piezometers showed water levels consistently lower than average during the year. The low water level in the piezometers reflects the dry conditions in the area and the lack • of run-off reaching the sediment pond.