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1 ' 3.0 HYDROLOGY AND MINE DEVELOPMENT ' This monitoring period from October 1, 1999 to September 30, 2000 has provided the hydrologic information necessary to assess the adequacy of monitoring program, the adequacy ' of the mitigative measures designed to protect the hydrology, and identify and quantify impacts that may have occurred during this period. ' 3.1 Mining Related Hydrologic Impacts ' The only impacts identified to date include: Withdrawal of water for the mine from the lagoon adjacent to the White River thus slightly reducing the flow in the White River. BME has legal right to this water. ' Discharge of storm water from ponds SS-1, RP2/3 and RP4 into Red Wash and DP-1 into Scullion Gulch, White River tributaries. Discharges contained lower TSS than typical ' receiving stream flows during storm events. Decline in piezometric level in wells in close proximity to mine workings. Holes that were ' mined through typically turned dry. ' Subsidence in Red Wash resulting in ponding of surface water. The ponds quickly fill with clay and silt with Red Wash maintaining its original channel. ' 3.2 Comparison of Projected Impacts with Observed Impacts ' The comparisons of the projected impacts (probable hydrologic consequences) with the observed impacts are discussed in the following. ' The water withdrawal rate from the lagoon in the White River Alluvium this reporting year was ' estimated at 123,656,595 gallons or 379.51 acre-feet. This compares with an expected withdrawal rate of 552 acre-feet per year at full production. ' The decline in piezometric levels in bedrock zones "upper sandstone facies", "siltstone/coal facies", and "lower sandstone facies" was anticipated as probable impacts as the result of ' underground mining activities. As projected these impacts are localized and will most probably continue in the proximity of the mined area. ' 1z