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<br />-zB- <br />applicant predicts a 0.14 cfs maximum decrease in ground water <br />contribution to Fish Creek due to the loss of ground water currently <br />discharging to the streams from the Wadge coal-overburden (p. 2.05-49). <br />This number reflects a maximum loss of ground water tributary to fish <br />Creek when the hydrostatic surface of the overlying aquifers is above the <br />level of Fish Creek and its alluvium. <br />There also is the potential of depleting water from the Fish Creek <br />stream-alluvial system by recharging the underlying Wadge coal-overburden <br />aquifer over four miles from the mine in Section 2, T6N, R86W. This <br />depletion would occur only if the drawdown cone produced by the mine <br />extends to the present discharge area. However, during the five-year <br />permit period, the drawdown of this aquifer will not extend below the <br />discharge area (see Figure 5). Therefore, during the 5-year permit <br />period, the Foidel Creek Mine will not produce any direct withdrawal <br />depletion of flows in the fish Creek stream-alluvial system. <br />The applicant used a maximum design inflow rate of 65U gpm in their mine <br />plan and in their assessments of hydrologic impacts. Most of the <br />projected mine inflows will be discharged to sediment ponds and <br />eventually to Foidel Creek. Any water required for operations within the <br />mine will be supplied by outside fresh water sources. A minor amount of <br />inflow water will be consumed as increased humidity in ventilation air (9 <br />gpm) and increase moisture adsorbed on the coal leaving the mine (7 gpm). <br />The applicant will monitor mine inflow rates, ground water level <br />declines, discharge rates, and consumption of water within the mine (see <br />Hydrologic fonitoring Plan, Exhibits 10, l0a and lOb•of the revision <br />application). Results of the monitoring will be submitted quarterly to <br />the Division to verify the applicant's predictions. <br />One additional area should be monitored. This area is the Wadge <br />coal-overburden discharge point on Fish Creek. Therefore, the Division <br />proposes the following stipulation to the permit to ensure that the <br />potential impacts of mining are adequately monitored as required under <br />Rules 2.05.6(3)(b)(iii) and 4.05.13. <br />Stipulation No. 1 <br />TO VERIFY THE APPLICANT'S PREDICTIONS OF STREAM DEPLETIONS IN THE <br />AREA OF THE WADGE COAL-OVERBURDEN AQUIFER DISCHARGE AREA ON FISH <br />CREEK, THE APPLICANT SHALL INSTALL AND MONITOR A SET OF NESTED <br />PIEZOMETERS COMPLETED IN THE ALLUVIUM OF FISH CREEK OVERLYING THE <br />SUBCROP OF THE WADGE COAL-OVERBURDEN AQUIFER. A PLAN SHALL BE <br />SUBMITTED WITHIN 30 DAYS AND THE WELLS SHALL BE INSTALLED WITHIN <br />120 DAYS OF ISSUANCE OF THIS PERMIT. THE WELLS SHALL BE MONITORED <br />MONTHLY FOR WATER LEVELS AND THE RESULTS OF MONITORING SUBMITTED <br />QUARTERLY TO THE DIVISION. <br />Springs and seeps which discharge from the Wadge coal-overburden aquifer <br />may experience diminished flows. However, the applicant has not located <br />any springs or seeps issuing from this aquifer in the permit or adjacent <br />