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The effect of releasing sediment-deficient waters from the sediment ponds should be minimal. Any downcutting should be limited to the point of discharge and immediately downstream. The gradient from the sediment pond is relatively flat, thus erosive velocities should not be attained. A technical assessment of the effects of undermining Rapid and Cottonwood Creeks was completed by the Division. The analysis shows that in the absence of subsidence or flow through natural fractures changes in flow would be insignificant, and there would be no material damage to downstream users. The applicant will be mining beneath the stream valleys according to a limited extraction plan. Therefore, possible subsidence effects should be avoided. The possibility of flow through natural fractures is difficult to predict. Major fractures Such as a fault would normally be identified during resource evaluation, and none has been identified by the applicant. Minor fracture (jointing) is ubiquitous in sedimentary rocks. However, joints may be open or closed to the passage of water. Their effect cannot be accurately predicted, but can be monitored. It is therefore appropriate to monitor the stream-alluvial aquifer system during mining and reclamation, and to identify the appropriate mitigations that would be undertaken should monitoring identify an undesired effect. Presently, there are three surface water monitoring stations located on Rapid and Cottonwood Creeks. One is located downstream from the permit area below the confluence of the two drainages. The remaining two are situated upstream from the 5 year term permit area, one on Rapid Creek and the other on Cottonwood Creek. The measuring devices are sized to show seasonal flow variations and provide accurate measurements during low flow periods. The gauging stations are equipped with continuous recorders, and data is gathered quarterly and submitted to the Division on an annual basis. As previously stated, in the absence of subsidence, there should be no significant effect on the flow in Rapid Creek and Cottonwood Creek. However, in the unlikely event that surface flows were depleted through natural fractures or subsidence related fractures, the applicant would be required to mitigate the effects from mining. To facilitate this, the applicant has supplied a contingency plan which describes the measures that will be undertaken to provide water to downstream users in the case that the surface and ground water monitoring indicate that the mining operation is having an adverse effect upon those users. In addition, if the proposed mining operation does deplete the flow in Rapid Creek and Cottonwood Creek, the water in the alluvial aquifer would also be depleted. This would not be immediately discernable from surface water monitoring or from inflow monitoring in the mine. Therefore, in order to provide an indication as to whether any increased mine inflows were due to depleting a perched aquifer or were due to depletion of alluvial ground water," the applicant has installed a monitoring well system within the alluvium of Rapid and Cottonwood Creeks. The system consists of two wells each in the Cottonwood and Rapid Creek alluvium directly over the mine workings. At each location, the wells have been completed to bedrock. One well at each location contains perforated casing throughout its entire length and the second well at each location contains perforated casing only in the lower most portion of the alluvium. -19-