Developing one of the world’s largest copper deposits

BHP and Rio Tinto have taken a major step in developing one of the world’s largest undeveloped copper mines.

The proposed joint venture, Resolution Copper, located in Arizona’s Tonto National Forest, has been under review for several years.

The US Forest Service, under the Department of Agriculture, published a final environmental impact statement and will enable future underground mine development subject to a range of conditions.

This marks a significant milestone, after a lengthy decade-long stakeholder process to co-design the underground mine and associated surface support facilities within the footprint of the historic Magma copper mine.

Resolution Copper welcomed the development, calling it a “positive step forward for the project” that allows the Forest Service to “advance the congressionally mandated land exchange”.

“This project has undergone one of the most comprehensive environmental and social reviews in US history,” Rio Tinto Resolution Copper president and general manager Vicky Peacey said.

The approval follows the US Supreme Court’s decision to decline an appeal against the project, removing a major hurdle for the mine’s progress.

“The Resolution Copper mine is vital to securing America’s energy future, infrastructure needs and national defense,” Peacey said.

The project is expected to create nearly 1500 jobs and generate significant tax revenue for Arizona and the US federal government. It was previously selected for fast-tracked federal permitting under Trump’s current presidential-era executive order designed to boost domestic mineral production and reduce foreign dependence.

Resolution Copper is a joint venture between Rio Tinto (55 per cent) and BHP (45 per cent), with Rio Tinto as the operator. More than $2 billion has already been invested in the development, which lies in Arizona’s Copper Triangle.

The mine hosts a deposit containing more than 18.1 million tonnes of copper, enough to meet up to 25 per cent of future US copper demand. Rio Tinto plans to use a caving extraction method to reach the orebody over 2000m below surface.

Once operational, Resolution Copper is expected to become North America’s largest copper producer, supporting thousands of direct and indirect jobs over its projected multi-decade lifespan.