1980-07-11_REVISION - M1977493 (8)

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portions of the area had been road. Prior to dumping operations , portions of the area had been used for a gravel operation but most of the area was natural talus slope and fellfield . Final dump slopes are approximately 1 . 3 : 1" ( angle of repose) . The Cirque Waste Rock Dump capacity of 36 million tons was reached during 1980 of Phase II and affects approximately 133 acres . The McNulty Waste Rock Dump ( 6 ) will be a primary waste rock disposal area for the Open Pit and will remain active throughout the life of the Open Pit. Preparatory site work includes tree removal , topsoil stripping for dump sta- bility, clear water diversion facilities and utility reloc- ation. Ultimate acreage of the dump is approximately 443 acres. Topsoil has been used immediately for reclamation purposes or stockpiled (7) . Approximately 35,000 cubic yards of topsoil have been stripped to date . A total of approximately 250,000 cubic yards is available to be stripped during Phases II and III and used similarly. ! The lowest section of the dump is located near the mouth of McNulty Gulch at an elevation of 11 , 170 feet, while the upper section is near the head of McNulty Gulch at an elevation of 12, 400 feet. The dump is designed in 100 foot , lifts with bank slopes approaching 1 . 3: 1 . The overall slope will range from 3 : 1 at the lower end of the dump to 2 . 5: 1 else- where . This design provided 100 to 150 foot wide access benches at every 100 foot lift. 2.5 UNDERGROUND MINING Main access to the underground mine is through the Storke Level (5 ) portal . No. 4 Shaft services the 600 and lower levels from the Storke Level with men, materials and muck hoisting and is enclosed underground. No. 5 Shaft provides access to the surface and service to the lower levels. It functions for men, materials and construction hoisting. No. 7 Shaft contains the main ventilation and electric power supply to the Storke and lower levels . Construction will commence 2-6