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Connell Resources Timnath Connell Pit August 24, 1999 PROPOSED GROUNDWATER CONTROL AND ROUTING SYSTEM • Two recharge ponds will be excavated on the south side of the site that will be utilized for rechazging groundwater to the aquifer downstream of the reservoir liner. • Three groundwater collection trenches will be excavated on the north side, into the undisturbed sand and gravel to a depth of approximately six feet that will be utilized for capturing groundwater and diverting the water to the rechazge ponds. • Two trenches will be located along the north end of the property and one will be located along the west property line. • The trench along the west property line will flow directly into the two rechazge ponds. • Culverts will be used to connect the trenches to allow flow between the trenches. • Agate will be installed on the culvert between the trenches at the northwest corner of the site and a gate will be installed on the culvert between the trench and an existing culvert under County Road 5 (culvert empties to the Poudre River). • The northwest gate will be operated to control groundwater movement azound the site to maintain natural groundwater levels on [he north and south side of the lined reservoir. • The northeast gate will be used to divert water to the river in the event that the mounding of the water table on the north is not being fully controlled by routing water to the recharge ponds. • The six monitoring wells installed on site will be used for monitoring groundwater levels for the operation of the drain system. • A siltation pond will be created for the dewatering water to settle out any fines/silt prior to the water being routed into the recharge ponds. Once dewatering is no longer needed, the siltation pond will be removed. MINE DEWATERING AND TRENCH INSTALLATION PHASE 1: Rechazge ponds will be excavated to bedrock. The south perimeter of the recharge ponds will be mined at 3:1 (H:V) slopes and no backfill material will be place along the slopes in order to maintain an unrestricted flow to the aquifer. As the east recharge pond is excavated, the groundwater will be dewatered to Mallard Creek through the existing drain tile. During the excavation of the west recharge pond, the groundwater will be dewatered to the east recharge pond. PHASE 2: During the mining of Phase 2 the groundwater will be pumped into the two recharge ponds. As Phase 2 is reclaimed the groundwater collection trench will be excavated. The trench will be used as needed during Phase 2 to maximize the groundwater flow to the dewatering ponds.