Sunshine Mining Company 



The Sunshine Mining Company of Kellogg, Idaho, submitted 

 an application in January 1988 to mine gold and silver at the 

 Big Blackfoot Mine three miles west of Lincoln. The proposed 

 mine area is located on private lands controlled by Sunshine 

 Mining and on portions of federal land (Helena National 

 Forest) . The application is still in the completeness review 

 stage. The Forest Service has recently decided that an EIS 

 will be required, while the DSL is proceeding with a prelimi- 

 nary environmental review (PER) before deciding whether an 

 EIS will be necessary. 



The project site is in the southwest portion of Lincoln 

 Gulch, which is tributary to the Blackfoot River. The mine 

 pit would be directly north and west of the Blackfoot River, 

 and the ore processing facility would be in the basin of an 

 intermittent drainage that flows east to Lincoln Gulch. The 

 operation would utilize standard open pit mining methods, ■' ■ 

 including topsoil salvage, ripping and blasting of rock, and 

 a truck-shovel operation for loading and hauling. The open 

 pit would be developed in four sections, with the first two 

 sections of the pit backfilled with waste rock and overburden 

 from the last two sections. Waste and overburden from the 

 first section of the pit (about 660,000 tons) would be placed 

 in a waste rock dump, which would be revegetated along with 

 the backfilled portion of the pit during the life of the mine 

 (Sunshine Mining Co. 1988) . 



The proposed operation would produce approximately 2 . 3 

 million tons of ore. The ore would be transported to a 

 crusher, located at the leach pad facility about 1.5 miles 

 from the Blackfoot River, where it would be crushed to three- 

 inch minus. The leach pad would be a total containment 

 facility with a double liner system and a net precipitation 

 storage pond. A specialized water monitoring program for the 

 leach pad facility would be maintained during the operational 

 and post-operational phases of the project. Reclamation of 

 this facility would include a procedure to neutralize the 

 residual cyanide in the ore pile. 



The project would require approximately 60 gpm of water, 

 which would be derived from two wells and the precipitation 

 pond. After the first year, most of the water would come 

 from the pond. Potable water would be obtained from on-site 

 wells. 



The operation would employ a maximum of 55 people. The 

 project is expected to have a seven-year life; however, if 

 the leaching process proved economical beyond year seven, it 

 might be extended. 



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