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to prevent geotechnical issues in WHEX. <br /> 3.6.3 Impact of Underground Exploration and Mining <br /> • Page 17: The text states that the proposed underground mining operation will"be located <br /> entirely in the vadose zone above the water table, and will only intersect meteoric water <br /> that infiltrates immediately above the mine workings", estimated to be approximately 3 <br /> gpm. Does this require additional water rights?If so, have they been obtained? <br /> RESPONSE: As noted above, a water rights augmentation plan is in position to <br /> accommodate impacts to water rights. CC&V(now Newmont Mining) is currently <br /> negotiating a modified agreement for water rights augmentation with potentially affected <br /> water rights holders. Chicago Tunnel is included in the area covered by this and prior <br /> agreements. <br /> • Plate 11 —Perched and Bedrock Water Table Depths shows the bedrock groundwater <br /> depth from ground surface in the region of the proposed underground operation to range <br /> from approximately 300 - 1,000 feet. What is the maximum expected depth of <br /> disturbance for the underground mining operation? Is there potential for the <br /> underground mine operation to intercept the water table in this area? <br /> RESPONSE: The maximum expected depth for Amendment ]] underground operations <br /> is 750 feet. Our current plan is to do exploration work and test mining. If a resource is <br /> confirmed and mining were to progress to the water table, water table impacts would be <br /> assessed and permits obtained, if needed. But at this time, there is no expectation that the <br /> water table will be intercepted. <br /> • Does the area of the proposed underground operation (located in Precambrian rock <br /> separating the eruptive centers) have sufficient vertical hydraulic gradient to drain <br /> into the diatreme fast enough as to not have a significant impact on the underground <br /> operation? <br /> RESPONSE. The currently identified underground resource resides on the margin of the <br /> volcanic and Precambrian rock and is controlled by vertical structures. The current <br /> underground workings are dry within the resource area. Drilling has resulted in dry <br /> conditions to date and circulation is lost during drilling indicating that the water used for <br /> drilling is draining out of the formation. We do not see there being an impact to the <br /> underground operation. <br /> • Will the new activities associated with the proposed underground mining operation <br /> have an impact on the Cripple Creek drainage system? <br /> RESPONSE: No. As noted above, drilling and piezometer data in the vicinity of the <br /> proposed Amendment 11 underground mining discloses dry conditions down to and below <br /> the proposed maximum mining depth. Accordingly there will be essentially no inflow to <br /> Amendment 11 underground mining activities, and no impact on the Cripple Creek <br /> drainage system is expected. <br /> • Plate 12 Infiltration Capture by Diatreme shows the Chicago Underground Tunnel <br /> trending northwest into Poverty Gulch, and terminating directly into or below the stream. <br /> How will the operation work to minimize impact to Poverty Gulch, and thus,to the <br /> Cripple Creek drainage system? <br /> RESPONSE: The Newmont water management plan for the Chicago Tunnel <br /> underground requires zero discharge. Water will be collected in sumps underground, and <br /> recycled into mine operations. It is anticipated that additional water will be required to <br /> Page 7 of 28 <br />