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cause slope failure problems at the head of this drainage. • Mining in the southern part of the area could affect stability of the existing active landslide complex above the road adjacent to Sage Creek in section 19, as well as affect future topsoil stock pile locations. There are several other landslide deposits which could affect or be affected by mining in this southern pit area as well. Tab 13 Facilities ' There appear to be conflicting opinions of sediment pond cut off ability and construction parameters which need to be clarified/resolved. Attachment 13-5, page 7 warns of shallow groundwater, soft, deformable soils, deep bedrock, and potential unacceptable seepage rates that may require a special design involving a clay liner. It further states that dewatering measures may be necessary during and after construction is completed. Attachment 13-7, page 9, indicates no unusual conditions in the pond 010 embankment area. What actually is the case here? What is the likely hood of unacceptably high seepage around/under the embankment? The clay liner possibility, potential high groundwater, and construction difficulties are not discussed in attachment 13-3, "Preliminary Construction Plan". If a clay liner or dewatering effort is indeed required, it is better to incorporate these into the proposed design prior to construction, than to have to return later and re-do the pond because it leaks too badly. ' The road proposed from the 1999 pit down to pond 011 will be constructed through an area of landslide/mudflow deposits, some of which appear relatively young. What is the potential for renewed instability in this drainage as mining and road construction disturb the head of i[? Why couldn't pond 011 be accessed from Grassy Creek? ' Stabilities and factors of safety calculated for haul roads assume there will be no seepage encountered in the cuts or beneath fills. Test holes were drilled in October 1993, a very dry period. Attachment 13-5 warns that the risk of slope instability will be "significantly increased" if seepage is encountered. What data exists to determine the potential for seepage to occur in haul road cuts during wet seasons and spring runoff? I am concerned that there is a real potential for some groundwater to occur in the haul road cuts, at feast during certain times of the year. What factors of safety will result from the assumption that some groundwater can be expected at certain times of year? What additional measures may be required to stabilize cuts and fills if groundwater is present?