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3.0 HYDROLOGY AND MINE DEVELOPMENT <br />This monitoring period from October 1, 2013 to September 30, 2014 provided the hydrologic <br />information necessary to assess the adequacy of monitoring program, the adequacy of the <br />mitigating measures designed to protect the hydrology, and identify and quantify impacts <br />that may have occurred during this period. <br />3.1 Mining Related Hydrologic Impacts <br />The only impacts identified to date include: <br />■ Withdrawal of water for the mine from the lagoon adjacent to the White River thus <br />slightly reducing the flow in the White River. BME has legal right to this water. <br />■ Discharge of storm water from pond DP -1 into Scullion Gulch, a White River tributary. <br />Discharges contained lower TSS than typical receiving stream flows during storm <br />events. <br />■ Decline in piezometric level in wells in close proximity to mine workings. Holes that <br />were mined through have turned dry. <br />■ Subsidence in Red Wash resulting in ponding of surface water. The ponds quickly fill <br />with clay and silt with Red Wash maintaining its original channel. <br />■ Subsidence in Scullion Gulch resulted in no surface hydrologic consequences observed <br />to date. Not enough precipitation has occurred to truly test the system. Runoff was <br />rarely observed in the impacted sections of Scullion Gulch prior to mining. <br />3.2 Comparison of Projected Impacts with Observed Impacts <br />The comparisons of the projected impacts (probable hydrologic consequences) with the <br />observed impacts are discussed in the following. <br />The water withdrawal rate from the lagoon at the White River this reporting year was <br />estimated at 121,382,510 gallons or 373 acre -feet. This compares with a projected <br />withdrawal rate of 552 acre -feet per year at full production. <br />The decline in piezometric levels in bedrock zones "upper sandstone facies ", "siltstone /coal <br />facies ", and 'lower sandstone facies" was anticipated as probable impacts as the result of <br />14 <br />