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6 <br /> to state where the lower American Tunnel bulkhead will be <br /> set . Based on the elevation of the portal (10, 617 feet) the <br /> bulkhead could be around 10, 750 feet . Thus, there will be <br /> 750 to 1, 750 feet of head on the single bulkhead. It seems <br /> very unlikely, based on the limited information available on <br /> the condition of the ground underlying the Sunnyside Basin, <br /> that SGC will be successful in eliminating inflow from the <br /> Lake Emma area. This almost guarantees that the head on the <br /> plug will be much greater than 750 feet. <br /> 7 . Page 24 , Third Paragraph <br /> The report discusses placement of three additional plugs to <br /> prevent movement of fluids via flooded working area of the <br /> Terry Tunnel or into the Mogul Mine. There is no discussion <br /> regarding potential movement into the Gold King properties <br /> via fractures or into the Mogul Mine via fractures. <br /> Shutting off flow along the Breneman Vein using two plugs <br /> may be a tall order. These reports contain insufficient <br /> information which would allow me to conclude that <br /> significant flow into adjacent mines via vein or fractured <br /> structures will be eliminated. A map showing all of the <br /> properties and the surface expression of all major faults <br /> and veins is needed. <br /> 8 . Pages 31 and 32 <br /> I question the interpretation of the borehole discharge test <br /> results which are presented in this section. The straight <br /> line nature of the test results for Boreholes 709 and 781 <br /> indicate that flow is related to a single fracture system <br /> and not a fractured rock mass system. Thus, the resulting <br /> hydraulic conductivity values are suspect. A more <br /> appropriate method for developing velocity information would <br /> be to use a Hele-Shaw Parallel Plate Flow Model . This would <br /> result in a much higher conductivity value. <br /> 9 . Section 8 . 0 <br /> This section attempts to calculate the approximate time for <br /> flow out of the mine to begin impacting the various streams <br /> in the area. I have doubts as to the validity of the <br /> various assumptions used to determine the flow time. The <br /> authors assumed that the borehole test data represents <br /> highly fractured media. I question this assumption. The <br /> data appears to represent flow through a limited fracture <br /> system. This is supported by the information indicating <br /> that boreholes were drilled into fractures overlying the <br /> American Tunnel level which had significant pressure heads. <br /> This would indicate that flow velocities in fractures <br /> connected to the various mine workings could be much higher <br /> than presently assumed. <br />