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• 1993 Annual Hydrologic Report Page 2 of 990 uhmos/cm. In September the conductivity of SP-3 was 750 uhmos/cm which is greater than is historic high of 666 uhmos/cm. The pH of the spring water, both SP-1 and SP-3, is within an acceptable range. The enclosed graph shows that the conductivity of spring SP-1 has consistently been below its historic maximum during the period 1989 through 1993. For Spring SP-3, the enclosed graph shows that its conductivity has consistently been above its historic average and below its historic maximum except during the current year when the measured conductivity of SP-3 was greater than it historic maximum. Further monitoring of SP-3 during 1994 will be necessary to determine if the water from the flooded mine workings is discharging into the alluvial aquifer and therefore impacting the quality of the water in SP-3. The hydrologic monitoring program provides for 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 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 460 and 388 respectively. In September the TSS for SP-D and SP-DA was 102 and 70 respectively. The TSS measurements taken in May and September indicate that no degradation of the quality of flow occurred on this stretch of the Carbon Ditch. The sediment pond did not discharge during the year. The pond did not have any significant amount of water in it during the year. A "spring" was noted is the northeast corner of the pond. During November the pH and conductivity of the Spring was measured (ph = 8.0 cond = 1470). GROUND WATER Table G-92 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 consistent with prior years averages. MINE WATER • The underground workings were not accessible for mine inflow monitoring in 1993 nor will they be accessible in the future. The