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Comments from the Willow Creek Reclamation Committee Regazding: Bulldog Mine Reclamation Project, Technical Revision 011, dated May 2002 Date: June 13, 2002 This technical revision was presented as an agenda topic at the regularly scheduled Juue 12, 2002 Willow Creek Reclamation Committee (WCRC) meeting. The Technical Advisory Committee (TAC) is an arm of the WCRC. The TAC has reviewed Homestake's proposed reclamation improvements for the 9700 and 9360 level waste rock dumps and have the following comments. The WCRC requests that the State Division of Minerals and Geology and the Forest Service, as land manager, carefully consider these comments before approving the reclamation project. As background, it should be noted that the US Forest Service originally intended to deal with Windy Gulch metals contamination under their CERCLA authority. At the request of the WCRC, the Forest Service agreed to allow final reclamation of these waste rock dumps using the State's authority for reclamation through its Mine Permitting process. The Forest Service is part of that process and must concur on final reclamation of sites on National Forest System Lands. The WCRC hopes that reclamation will be sufficient to prevent the need for future implementation of CERCLA authority. COMMENTS: We have four main issues that we feel strongly should be dealt with in the final reclamation plan In addition, we are including some minor points that we believe need consideration as well. 1) Depth of cutoff walls The plan says that cutoffwalls above both dumps will be keyed into the bedrock. During a field visit to the site the Forest Service asked Homestake how deep they would have to go to hit bedrock and whether they can realistically go that deep. Homestake did not know for sure at what depth bedrock occurred and could not say for sure that they could really place the cutoffwall that deep. Subsurface water probably moves along the contact between bedrock and alluvium and through the more porous medium lying on top of the bedrock. The Committee feels that it is important to contact bedrock with the cutoff walls in order to capture this flow. We have similar concerns about fracturing in the bedrock that could also intercept the flow. If faulting or fracturing occurs in the vicinity of the cutoff wall placement, success of this technique will be limited. Constructing wing walls as part of the cutoff wall might help capture more of the subsurface water that might otherwise move around the wall. 2) Infiltration through the waste rock dumps. The Committee is concerned that infiltration through the dumps has not been adequately addressed. Local observations from azea residents suggest that snowmelt