Rio Tinto earmarks $108M for underground mining studies at Kennecott copper
(Kitco News) - Rio Tinto announced Thursday that it has approved a $108 million investment in underground development to enable early orebody access and undertake orebody characterisation studies for underground mining at the Kennecott copper operations in the United States.
According to the company’s statement, this investment builds on $25 million approved in early-2020 to complete a pre-feasibility study to determine the viability of underground mining operations at Kennecott. Potential underground mining would occur concurrently with open pit operations and result in increased copper output, the company said.
Rio Tinto noted that Kennecott holds the potential for a significant and attractive underground development, with declared Mineral Resources of 20 Mt at 3.65% copper and 1.62 g/t gold with further upside potential based on drilling.
Additionally, the project will also include the trial of underground battery electric vehicles to reduce carbon emissions at Kennecott and across Rio Tinto’s global operations. Sandvik Mining and Rock Solutions will supply a battery electric haul truck and loader to evaluate performance and suitability for future underground mining fleets, the company added.
Kennecott operates an advanced copper and precious metals smelter, processing concentrate from Kennecott and third parties. In addition to copper, Kennecott is one of the largest producers of gold, silver, and molybdenum in North America.
Construction is underway on a plant to recover tellurium, a critical mineral used in solar panels, from copper refining at Kennecott. Rio Tinto is working with experts from the US Department of Energy’s Critical Materials Institute on ways to extract further critical minerals from the existing refining and smelting processes.