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RECEI!!E® <br />MINING PLAN REVISIONS <br />OCT 1 6 2007 <br />1. General Mining Plan Revisions <br />GRAND JUNCTION FIELD OFFICE <br />DIVISION OF <br />RECLAMATION MINING & SAFETY <br />Currently this pit is permitted to mine 115 acres along the north fork of the Gunnison River. <br />Excavation was divided into five phases. Phase 1 lies on the northwest side of the permit, and is <br />sepazated from the other four phases by a 200 foot buffer. Phase 2 is immediately south of the <br />200 foot buffer and west of Phase 5. Phase 3 & 4 aze on the northeastern end of the property. For <br />the purposes of this technical revision, the phases have been relocated. Phase 1 and 2 remain in <br />there original location, with phase 3 being the old phase 4 plus the section of the 200' buffer <br />being removed, and phase 4 being to the ultimate northeast of the permit boundary. Most of what <br />was phase 5, which aze wetlands, will be left undisturbed. The new phase boundaries can be seen <br />on Map C-2. <br />As part of this technical revision, Tri County will mine out a section of the 200 foot riparian <br />buffer between Phases 1 & 2. An area of 8.0 acres will be removed as a result of this excavation. <br />In the original DRMS permit, the 200 foot buffer was set aside as wildlife habitat. In order to <br />encourage post-mining development of such habitats, the 8.0 acres of wetlands in the old Phase 5 <br />area will be lefr undisturbed. The operator commits to supplying irrigation water to the wetlands <br />within the old phase 5 azea in order to maintain them during mining. <br />Currently, the Tri County pit is permitted to mine all slopes to 3H:1V. As part of the technical <br />revision, all pit slopes will be mined to a fmal slope of 2H:1 V and will be reclaimed to a slope of <br />3H:1 V down to 10 feet below the water line, and then 2H:1 V to the lake bottom. <br />The Tri County pit will change from a wet pit with mining via track hoe, to a dewatered pit with <br />mining via loader and trucks. A pit pump will be installed in the western corner of phase 1, and <br />will pump to a sediment pond neaz the topsoil piles above the pit, immediately to the southwest. <br />As seen on Map C-3, the sediment pond will then discharge into the north fork of the Gunnison <br />River. An NPDES dischazge permit will be acquired for this operation. Since the existing <br />groundwater level is so close to bedrock, the pit pump will not always be below the mining level. <br />Tri County Technical Revision Sept 07 3 <br />