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amount of suspended material may be carried downstream during the initial construction of tt~e diversion, but this will not cause excessive sedimentation downstream. Once the river flows into the er.cavated area, the velocity will be reduced, thereby depositing the suspended material before the river joins the present channel at the north end of the property. At the conclusion of er.cavation during Phase II, once the riprap has been placed around the cottonwood tree area and the erasion control structure placed along the east low-water channel, the temporary diversion will 6e removed and the existing berm restored to its present condition. A small amount of suspended material may be carried downstream while the berm is being restored, but once the river is flowing into the Phase II er.cavated area, the suspended material will again be deposited before leaving the property. Neither event will cause e>;cessive sedimentation downstream. e. Two forty-eight inch culverts will 6e placed in the bottom of the Fhase I er.cavated area so that the loader and/or trucks may cross to the Phase II area without disturbing the flawing river. Exhibit C_ - Mining Plan 1. There is no waste rock on top of the deposit or within the deposit. All material excavated will be used for road base or fill ^ffsite, or for reclamation and/or the berm or diversion structures onsite. 2. The permit area has been revised to include the equipment storage/warehouse area as described in Exhibit 6 - Site Description, Item 1. The south boundary has been moved to the north approximately 100 ft so that the permitted area remains less than 10 acres (9.8 acres m/1). See Exhibit E - Map. 3. Please refer to the enclosed Huckhorn Geotech analysis dated February 10, 1992. ~ 4. The described mining plan is designed so that any I effects to water quantity or quality will be slight and temporary. As discussed in above Item S, Exhibit B - Site Description, water quality will not be diminished by siltation. Excessive downstream sedimentation will not result from the i berming, channeling or er.cavation since areas, which have the potential of providing finer material that can become j suspended, are controlled by riprap or a rail/wire structure. ~ Head-cutting and/or bank erosion are bath controlled by these f• measures. Downstream scouring will be very slight, as ~ discussed by Buckhorn, since the velocity of the river as it re-enters the existing channel to the north is very close to the present bank-full velocity. ~ Page 3