2008-04-21_HYDROLOGY - M1978091UG

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but is contained within the pad area and has not left any aerial residue to adjacent areas. This is likely due to the fact that the material does retain considerable dampness for sometime. All crushing and sorting is accomplished on the pad. Any residue is therefore an added layer of waste to the underlying waste rock. The rate of activity typically yields one haul truck per 3- 4 working days with no greater than 5 tons per haul truck. Spills are prevented by maintaining equipment and vehicles in operational conditions and keeping all fuels/solvents containerized, covered and suspended either on pallets or within storage. There are no tanks for fluid storage of any significant size on the Level 6 pad. Any spills that occur will be dealt with immediately in order to prevent any non-point source of contamination to stormwater. Currently, there are no fluids stored at the mine site. Historically, there were several 55-gallon drums as follows: a) one drum with residual drill fluids used for working on tools (removed), b) one drum empty and used for residual tool fluid storage (removed), c) one drum used to transport water used for hydraulic tools (removed). In addition, solvents and timber treatment fluids were once contained on pallets outside the portal. These materials have also been removed. When these materials were present, the mine operators had spill containment materials such as absorbant pads and drums used to contain excavated materials that were saturated with spill fluids. The waste rock can be considered another pollutant-containing material handled at the mine. The ore is typically damp when recovered and yields little to no dust. The crushing does create dust, however the amount of processing is slight. Observations of the crushing area indicate that very little dust and deposition is created. The crushed product is large in size and still typically retains some water. These factors lend to very little dust being formed. The waste rock can also lend acid rock drainage pollutants if stormwater comes into contact and percolates through the pile. Several management practices are currently in place to control stormwater from ever contacting the waste rock. The management practices that keep stormwater away from the waste rock include the contouring of the pad towards the cut slope, perimeter berms that keep water from flowing off the pad and onto the waste rock slope, revegetated berms along the perimeter to stabilize the berms themselves, and benching of the waste rock slope to prevent sheet flow from gaining energy down-slope and causing erosive rills along the face of the slope. Since the time of this SWMP, a diversion channel has been constructed as per manufacturer specifications in order to sufficiently contain Deadman Gulch flows and route them away from the waste rock pile. In addition, the waste rock pile will be removed from the native gulch channel beginning in 2008. iii. Sediment and Erosion Prevention Page 11 of 16