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Memo to Bob Oswald 6 December 20, 2004 <br />Golden Wonder Mine Permit No. M-1978-091-UG <br />1. Is the Gold Quartz vein sufficiently permeable to accept water from the mine? If the vein <br />cannot accept at least 10 gallons per minute under hydrostatic pressure alone, the <br />Operator's plan may not be feasible. <br />2. Is the ambient water in the Gold Quartz vein contaminated? Given the data collected for <br />the lower adit and the Gold Quartz discharge higher on the mountain, it is likely that the <br />water from the monitoring well will be severely impacted. Given the data for samples <br />collected in the Golden Wonder Mine, it is likely that water generated from deeper parts of <br />the proposed adit and proposed stopes will also be highly contaminated. These data are <br />based on samples collected by the Operator on March 29, 2004 and June 30, 2004. <br />Discharge of contaminated mine water into contaminated Gold Quartz vein water is <br />acceptable under the Interim Narrative Standard only if the discharge does not result in <br />worsening of Gold Quartz water, for any regulated contaminant, at a point of compliance. <br />If the water collected from the monitoring well is clean relative to the Golden Wonder <br />Mine water, the Operator's plan may not be feasible. <br />Depending on the outcome of the procedures for steps 1 and 2 described above, the Operator should next <br />prepare a contingency plan to manage water that may be encountered during driving of the adit or during <br />stoping that could exceed the relatively minor flows that are anticipated. The contingency plan should be <br />formulated to allow for containment and storage or treatment of flows that may be encountered in excess <br />of the assimilative capacity of the proposed boreholes leading to the Gold Quartz vein. The contingency <br />plan must necessarily include obtaining a permit under the Colorado Discharge Permit System <br />administered by the Water Quality Control Division; this permit is necessary to avoid discharging without <br />a permit, which could be a very grave violation of water quality laws, in the event that containment is <br />overwhelmed by unanticipated high flows in the mine. <br />Finally, the operator must gain approval of a plan for closure and reclamation of the proposed adit. This <br />must include reclamation of the waste dump and sealing of the portal for safety, and must include <br />measures to prevent discharge of water from the adit to surface. The Operator stated during the inspection <br />on October 13, 2004, that hydraulic bulkhead seals would be installed at the time of closure. The DMG <br />has considerable experience with bulkheading of underground workings, which is a closure method that <br />has proven effective in a number of cases, but has also proven to be problematic in some settings. Based <br />on this experience, DMG approves bulkheading only in mines that are found to be suitable. It is <br />imperative that the installation of bulkheads does not result in near term short-circuiting and discharge of <br />contaminated water to surface water bodies. <br />Some preliminary discussion of bulkhead design and cost (to be used for reclamation bonding purposes) <br />is appropriate at this time to determine initial feasibility for bulkheading of the proposed adit. Bulkheads <br />must be sited at a location in the adit where there is sufficient thickness of overlying rock to prevent <br />hydrofracing under the design hydrostatic pressure. The design pressure head may be determined as <br />follows: <br />First Ridge Elevation: 10,940 feet <br />POrtal Elevation: 8900 feet (use of portal elevation is conservative, since the Operator stated that the adit would be driven at an up angle) <br />Head @ Bulkhead: 10,940' - 8900' = 2040' <br />Pressure @ Bulkhead: 2040 ft. x 0.4331 psi/ft. = 884 psi <br />