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Mr. Louis F. Swift September 14, 1999 Page 2 t while water levels are remaining stable in the Swift Ponds. Six groundwater monitoring wells will be installed on the site and these will be used to operate the peripheral collection trenches. In conversations with you, it is understood that the Swift Ponds only fluctuate plus or minus approximately 1 foot from their normal operating levels, and the recharge ponds should be operated to ensure these levels. 2. Post-mining conditions The groundwater collection and conveyance wenches constructed at the commencement of operations will remain in place, though may be excavated and rebuilt during mining operations (for construction of the clay liner) to maximize the groundwater flow to the recharge ponds. At the completion of phase 2 operations (approximately three years from initiation of mining), the permanent collection and conveyance system to the recharge ponds will be in place on the west side of the property, and the western section of the collection trench on the north side should also be in place. As there will be nine more years of operations following completion of this phase, constant monitoring of the permanent system will be required during all months of the year (mining or no- mining) to ensure that the recharge ponds aze operating satisfactorily and the Swift Ponds' levels are deviating no more than plus or minus one foot from their normal operating levels. For this surface water fed recharge system, there are two concerns that may restrict the recharge system to the Swift Ponds. These are: • potential for freezing or aufeis development within the conveyance trenches on the north and west sides during the winter months, and • the potential for "blinding off' of the south wall of the recharge ponds due to silts and clays not intercepted by the siltation pond. If either of these potential concerns become realities during the last nine years of operations, an alternative water conveyance and recharge system will be required to protect the water levels within the Swift Ponds. A possible alternative system would be the design and construction of a French drain system around the entire perimeter, buried approximately ] 0 feet beneath the surface. This drain should be constructed of corrugated/perforated (double-walled if available) FIDPE pipe embedded within a graded filter medium compatible with the natural alluvial material. The use of synthetic filter fabric would not be recommended for this application. If an alternative system is required, the system should be designed and installed as eazly as possible during the phase 3 or 4 operations to allow additional corrective action time during mining operations. RECOMMENDATIONS Prior to approval of the permit, we recommend that the following be conducted and included within the plans and written agreement between Connell Resources and yourself.