Abstract

The Bingham Canyon mine, located southwest of Salt Lake City, Utah, is wholly owned and operated by Kennecott Utah Copper Corporation (KUCC), a subsidiary of Rio Tinto. Current daily production from the open pit mine is about 143,000 tons of ore and 256,000 tons of waste making a 1.8:1 waste to ore stripping ratio. In 2008, the deposit produced 221,000 tons of refined copper, 11,675 tons of molybdenite concentrate, 303,000 ounces of gold, and 3,250,000 ounces of silver. The current planned open pit mine life extends to 2019. Substantial mineralization and exploration targets exist outside of the current mine plan and several options are being studied to evaluate the viability of extending the Bingham Canyon mine life beyond 2019.

Rio Tinto/KUCC began their current study of the potential for bulk underground mining and/or an additional open pit pushback of the present design at Bingham Canyon in 2005 and an order of magnitude study was completed in 2006. Four bulk mineable underground targets as well as one open pit extension have been identified and are currently being reviewed for their economic feasibility. The pushback expansion consists of the South Wall and Highland Boy area of the pit. The prospective block cave and long hole stope targets are the Northeast cave, Southeast cave, Highland Boy cave, and the North Rim skarn. In addition, there are several exploration targets that will be investigated by the expansion studies team in the near future. Several future mining scenarios are being evaluated which will include the surface pushback extensions in conjunction with the extraction of one or more of the underground targets. This paper takes a cursory look at these open pit and underground expansion options.