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Monitoring of water levels and water quality of the Trout Creek aquifer <br />will take place in four wells throughout the basin. Monitoring will <br />occur on a semi-annual basis (Exhibit 14). <br />The Wadge overburden monitoring wells were the subject of considerable <br />discussion prior to issuance of the Findings. The Division requires the <br />applicant to re-submit Exhibit 14 showing monitoring of Wadge overburden <br />wells 006-81-31, 006-82-48, 009-79-4 and 006-82-74. Additional <br />monitoring will be required to verify permit projections of mine water <br />inflows. These should include: monthly recording of mine inflow <br />discharges, an annual mine water inflow evaluation every December, and <br />quarterly mine water consumption records. <br />STIPULATION N0. 2 <br />THE PERMITTEE WILL SUBMIT A REVISED EXHIBIT 14 WITHIN 30 DAYS OF PERMIT <br />ISSUANCE WHICH INCLUDES MONITORING OF FOUR WADGE OVERBURDEN WELLS: <br />006-81-31, 006-82-48, 009-79-4 and 006-82-74. IN THIS PLAN THE PERMITTEE <br />WILL COMMIT TO QUARTERLY SUBMISSION OF MONITORING DATA, AND THE SUBMITTAL <br />OF AN ANNUAL HYDROLOGIC REPORT (AHR) WHICH INTERPRETS THE PREVIOUS YEAR'S <br />DATA AND LONG TERM TRENDS ON OR BEFORE FEBRUARY 28 OF EVERY YEAR. <br />No dewatering of the Twentymile sandstone is projected, as that aquifer <br />is separated from the Wadge by 700 feet of low permeability shales. <br />Subsidence calculations show rubblization following retreat to extend <br />only 300 feet above the current workings, and the applicant projects no <br />impact to the Twentymile sandstone. Two bedrock wells will monitor this <br />aquifer to verify these conclusions. <br />The relationship between ground water and surface water on Foidel and <br />Fish Creeks was discussed. Typically alluvium is recharged by surface <br />waters during high flows, and discharges to the streams during low summer <br />flows to produce base flows. TCC provided documentation that Foidel <br />Creek alluvium in Section 21, downstream from the portal was dominated by <br />clays and silts and had a low permeability. Consequently, this area <br />showed little seasonal fluctuation in alluvial water levels and recharge <br />was primarily from precipitation events and associated runoff. <br />Fish Creek is a typical gaining stream throughout most of the year, <br />except during the irrigation season when over appropriation of water <br />rights in the area between Mine 2 and Fish Creek's confluence with Trout <br />Creek creates a losing reach. The applicant had indicated that 25% of <br />Fish Creek's baseflow was derived from ground water recharge. Later <br />clarification noted that this reference was discussing recharge upstream <br />of all of Cyprus Western's properties and outside Twentymile Park. <br />The Division continues to question the veracity of the conclusions <br />reached about recharge and discharge to alluvial aquifers. Verification <br />of these conclusions could be accomplished through the placement of a <br />staff gauge in the stream adjacent to each alluvial well, and recording <br />of the stream height coincident with well monitoring. <br />-15- <br />