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• 83, The interpretation is made on page G-13 and G-50 that no measurable gains or losses in streamflow occur through the mining property. A comparison of Tables G.2-2 and G.2-3 indicate there to be predominantly losses of varying magnitude occurring along the reach. The data indicate on the occasions of a gain that the amounts are generally of lesser magnitude. Please evaluate and discuss. 84, No statement is made concerning the probable hydrologic impacts to surface water due to the mining operations. Although the continuing surface water monitoring program is designed to denote any changes, please discuss whether any changes in streamflow, water quality or sediment loading are expected during the mining and reclamation phases of the operation, 85. Please specify which species of cyanide will be analyzed; it is recommended that free and total cyanide plus thiocyanate (a compound which often skews the free cyanide reading) be analyzed. 86, Please indicate the schedule for submittal of water quality moni=oring results to the Division. 87. Please include a ground water monitoring station down-gradient from the southern waste rock/tailing disposal facility, and a surface watE~r monitoring station downstream of the old heap area. 88. We are concerned that the quantity and duration of post-mining ground water inflows to the west pit may be greater than anticipated. The data presented does not appear adequate to completely substantiate the prediction that the pit will not contain permanent standing water after reclamation, For example, there is insufficient informatioi which shows how the pit will intersect the faults and fractures, such that their influence on the hydrologic system can be ascertained. It ''s likely that the horizontal and vertical extent of fracturing probably goes beyond the economically mineralized zone. Therefore, the lai:eral exterrt of this fracture-controlled aquifer may extend beyond the Fait area. It is also unclear whether dewatering will cause a hydraulic gradient reversal in the alluvial aquifer in the vicinity of Rito Seco and thus provide an unanticipated source of ground-water flow from the south. In order to resolve this concern, we suggest that Battle Mountain initiate further hydrologic investigations. These investigations should produce a predictive model which describes, given the additional research, the potential for continued post-mining pit inflow from ';he Rito Seco alluvium and the pre-Cambrian aquifer system. This mode should be completed prior to west pit disturbance, as the result may impact the proposed reclamation plan. If post-mining inflows are likely, two potential reclamation plan modifications will need to be evaluated. These alternatives are: -15-