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Bulldog Mountain Operation Operating Plan Page 3 Install a periphery tailings discharge system. The banks of the pond consist of porous alluvial and colluvial sediments that are not entirely sealed by the tailings. 4!ith the addition of a booster pump, bentonite can be added to the tailings and upon discharge, offer an effective seal. Currently, 10% solids are being discharged into the pond. It is anticipated that the present tailings line, a six inch drop system, can be increased to a 30% solids flow. Construct a slurry wall (cut-off trench) below the tailings dam. The slurry wall would be constructed over a distance of 400 feet, 3 feet wide and approximately 35 feet deep. The actual depth of the trench required to reach unaltered and firm ground will be determined by rotary holes drilled on 20 to 30 foot centers along the strike of the slurry trench. Any additives required in the bentonite mix for stabilization would consist of type II cement or products that are stable under known conditions. Construct a drainage collection trench uo stream from the slurrv wall. The collection trench would be installed prior to construction of the slurry wall to prevent excess water flow into the slurry wall trench ~.- during construction. The trench will be excavated along the entire ~'~' length of the slurry wall. The trench will be excavated by a backhoe to a depth of 8 to 10 feet below ground level, and back-filled with coarse to large river gravels. A drainage pipe may also be installed to channel any seepage to the center or low point of the collection trench wherein pumping facilities will be installed for return of seepage to the tailings dam. The material excavated from the collection trench would be used as compacted fill fora retention embankment dam. Construct a retention embankment dam on top of slurry wall. N,~~~~"f The dam would be constructed to a height of 12 feet above ground level. r'"P~ The compacted fill material would be excavated from the construction site. Depending on the impervious nature of the fill material, and to prevent any seepage, the slurry wall may also be extended up through the retention embankment. The retention embankment would be constructed on a slope of 2'1. A spillway consisting of coarse to large gravel, will be constructed to prevent any erosion of the dam from a 100 year flood. The upstream side of the retention embankment will be riprapped with coarse mine waste rock.