2005-10-24_REVISION - M1987028 - Laserfiche WebLink

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exposed along the western edge of the working pit, with a secondary jointing pattern, N90E, dipping 76 East, and a tertiazy jointing pattern measuring N67-70E, dipping 48 S, evident within the ore body. Jointing evidently imposes a high degree of control in rock breakage within the ore zone, the attitude of the mining face and fragmentation of mazble during extraction operations. The white mazble seam is bounded on its eastern and western margins by blue-gray mazble, hazd, crystalline metamorphic rock measuring app. 35 feet thick each side of the white mazble bed, measured where outcropping at footwall and hangingwall contacts. A veneer of white mazble has been left along the footwall (western) side of the mine cut in attempt to limit contanunation of the white during mining. Above the neazly vertical marble bed and to the west is a tree covered steep slope of rocky soils which continues for app. one half mile to the top of the Taylor Gulch Basin. The ground is steeply sloping and broken by a number of abandoned underground mining plays with associated muckpiles from former underground entries or shallow pits and remnants of small wooden mining structures. Forest Service Road 228, a narrow single lane jeep trail, crosses the slope above the mining cut and eventually tops out over the ridgeline about one half mile above and north of the mining azea. Slopes above the mining azea aze approximately 50%. The slope is tree covered for two to three hundred feet above the mining azea, then grades to grass and forbe covered rocky slopes to the top of the drainage basin. To the immediate east (hangingwall) of the marble seam, the blue mazble bedrock slopes steeply to the floor of Taylor Gulch, which drains in a southemly direction at 10-15% grade. Taylor Gulch is ephemeral drainage with a rocky narrow channel bounded by fir and aspen trees. The upper portions of the basin aze void of tree cover (with a few remnant stands of dead tree trunks) and several old mine dumps and entries. Taylor Gulch drainage is crossed twice by switchbacks of Forest Service Road 228 in the reach of the mine site and one additional time just above the mining zone. The two crossings within the mine site have been addressed by the mine operator to segregate mine site drainage from storm related and snow melt drainage of Taylor Gulch itself. Forest Service Road 228 may be re-located to the south of its present location in the future (10-15 yeazs) depending on the timing of mine progression to the north. Prior to road relocation, the operator will file for a technical revision with the DMG and approval with USFS. Mine Plan Narrative Future mine operations will employ conventional surface mining techniques of bulldozer, drilling, and blasting to extract white mazble as in the past. However, in order to create and safe and reasonable working face for mazble mining, both footwall and hangingwall zones immediately to the east and west of the mazble bed need substantial development work. First, affected land boundaries need to be expanded to facilitate highwall stabilization and footwall benching operations above and west of the marble bed. While two thirds of the proposed affected land boundary increase is necessary for access to the mazble in the future, about one third of the proposed fifty acres of additional affected lands is needed for highwall development(west ofmazble bed) and waste material placement along the southern mazgins of the existing disturbed lands. Second, highwall work via bulldozer and excavator will commence above the western edge of the mazble bed, intended to 1) direct surface drainage of snow melt, rain storm events, and seasonal