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MEMORANDUM <br />TO: Bob Oswald <br />FROM: David Bird <br />DATE: February 4, 2009 <br />RE: Review Comments on Golden Wonder Level 6 Hydrologic Setting Report <br />LKA International Inc., Golden Wonder Mine, File M-1978-091UG <br />This memorandum presents review comments from the staff geochemist for the Division of <br />Reclamation, Mining, and Safety (Division) regarding the Level 6 Hydrologic Setting Report for the <br />Golden Wonder Mine, dated December 2008. Following are general comments pertaining to the <br />conclusions of the report. <br />The Division is not convinced that the deeper ground water is the.primary source of water to the seeps, <br />for the following reasons: <br />1) The fact that the toe seeps have been dry in certain years vs flowing 200 gpm in others <br />suggests a seasonal impact that otherwise might not be as prevalent in a system fed <br />predominantly by deeper ground water. Is the liner capturing all of the water in Deadman <br />Gulch? Even if the liner is not compromised, what about shallow ground water flow or <br />interflow moving down the gulch? The variable discharge rate, combined with the location <br />of the toe seeps in a waste pile that virtually straddles the gulch, suggests that shallow <br />ground water flow/interflow may be a significant contributor to the seeps. The statement <br />on Pg. 20 that the results of the graphic techniques indicate that the water quality <br />characteristics of the waste rock toe seeps are closely associated to the Deadman Gulch <br />background water chemistry conditions provide strong support to this possibility. To test <br />the possibility of shallow ground water/interflow, some shallow monitoring wells are <br />recommended in Deadman Gulch, upstream from the pad and drilled to test the existence <br />of, depth to, and quality of shallow ground water, completed in the alluvial layer that <br />overlies the rhyolite, while being careful not to damage the liner. There appears to be a <br />healthy grove of aspen. trees directly above the mine, and aspen trees' needs for water are <br />another line of evidence suggesting shallow ground water moving down the gulch.. <br />Although the operator already has monitoring wells in the alluvium, it is questionable <br />whether the existing monitoring wells are free of influence by discharge from the mine <br />workings or by infiltration through the waste rock. <br />2) There does not appear to be discrete water quality or water level data from the deeper <br />rhyolite ground water - the very source that is hypothesized to be the primary source of the <br />seeps. Assertions that a particular hydrogeologic unit is a primary water source should be <br />backed up by a complete geochemical characterize of the unit including water quality data, <br />not merely rock geochemical data. The Division recommends installing a set of nested <br />monitoring wells upgradient of the level 6 pad that can definitively capture and differentiate