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CONCLUSIONS AND RECONINIENDATIONS Mining at the Duckworth Pit can be accomplished without detrimental effecu to Boulder Creek and wells and lakes surrounding the site. Based on the results of the modeling completed for the Duckworth Pit mining operation, the following conclusions and recommendations are made: Dtuing mining a maximum drawdown of 13 feet at a distance of 600 feet from the site is estimated as a result of the dewatering operation without the suggested mitigation efforts. • The maximum required rate of dewatering from the site during the miming operation is estimated at 1,141 gpm. Dtu-irrg mining, water collected in dewatering trenches should be ptunped into the existing unlined lake located directly north of the site. The water maybe delivered to the lake through Idaho Creek, however, measuring devices should be installed such that 100 percent of the water discharged into Idaho Creek maybe accounted for and delivered into the lake. The Rural Ditch Company conveys water through Idaho Creek in this area, therefore approval from the Rural Ditch Company will likely be needed. Groundwater levels to the south of the site should continue to monitored throughout the mining operation. It is not anticipated that the groundwater levels will fall below the depth of existing domestic wells in the area, however, should the groundwater levels fall below the depth of the pumps in the wells, the pumps should be reset at a lower elevation. ' • There does not appear to be a significant effect on the groundwater flow in the area as a result of the completion of the two unlined reservoirs at the site. ' • Water levels should continue to be monitored while the site is being dewatered and for a reasonable time period following reclamation to assess any long term impacts the two unlined lakes may have on the groundwater table in the area. Lafarge West, Inc. -8- Applegate Group, Inc. Duckworth Pi[ Groundwater Study March, 2004