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WELBORN DUFFORD BROWN 8 TOOLEY, P.C. <br /> Mr . J. David Holm <br /> May 26, 1993 <br /> Page Four <br /> through the Sunnyside Mine. Would this be subject to NPDES <br /> permitting requirements, or would it be handled under the same <br /> 1987 Division policy that covers other historic inactive mining <br /> portals in Colorado? Again, we request your position on this <br /> issue. <br /> (2) American Tunnel Below Property Line. Historic flows <br /> have occurred from the first 3500 ' of the lower portion of the <br /> American Tunnel since it was first driven in the 1920s . The pH <br /> of that water is generally acidic, and the flows derive from <br /> fractures and groundwater infiltration into the tunnel from <br /> near surface groundwater, snowmelt, and runoff in the surface <br /> geologic structures near the portal . There is no addition of <br /> pollutants or discharge of pollutants in that circumstance from <br /> any human activity, although there may be a "point source" at <br /> the portal . There has never been any mining activity in the <br /> area of the lower part of the tunnel, only the driving of the <br /> tunnel itself in the 1920s . Would an NPDES permit be required <br /> for that continuing flow, and who would be responsible for such <br /> a permit since it is below the property line of Sunnyside Gold? <br /> Alternatively, Sunnyside Gold, in conjunction with <br /> the Gold King property owner, could install a second or <br /> multiple additional seals in the American Tunnel to cut off <br /> flows from the portal . As above, the installation of these <br /> additional plugs would eventually result in ground water being <br /> backed up in the American Tunnel. The rising water pressure <br /> behind the plug would ultimately result in a return to an <br /> approximation of pre-mine ground-water flow directions. Ground <br /> water which presently flows from the American Tunnel will <br /> instead discharge at seeps and springs which were naturally <br /> present prior to mining. Would that return to natural <br /> hydrologic conditions result in any water quality permit <br /> requirements? <br /> (3) Lake Emma Reclamation. As part of the ongoing <br /> reclamation of the Lake Emma area, at an altitude of <br /> approximately 12,200 ' , surface runoff will be diverted by means <br /> of several ditches away from the former Lake Emma area so that <br /> it will not enter the mine workings . Additionally, certain <br /> "groundwater" in the loose rock near the ground surface in the <br /> basin will be intercepted and similarly diverted. Again, this <br /> is part of the planned reclamation in order to preclude part of <br /> the water in the Lake Emma basin from entering the mine <br /> workings . It would seem unrealistic to require a permit for <br /> any such structures and to monitor them into the future, given <br /> lack of mining activity and also given the climatic and <br />