Rio Tinto said it has moved a step closer to the development of the Resolution Copper project in Arizona, US following the publication of a draft environmental impact statement (DEIS) by the US Forest Service.

The review process included public engagement, with the permitting process for the Resolution project began in 2013.

The DEIS publication triggers a 90-day public consultation process to issue the final environmental impact statement (EIS), and next steps in the permitting process for the project.

Rio Tinto owns majority stake in Resolution Copper project

The project is 55% owned by Rio Tinto subsidiary Resolution Copper Company and 45% by BHP Copper.

The partners are planning to spend more than $2bn (£1.6bn) by next year on the development and permitting process of the Resolution Copper project.

Investments are being made in the reclamation of the historic Magma Copper Mine site, sinking a second shaft to mining depth, rehabilitating an existing shaft, extensive drilling and ore body testing, in addition to the permitting and public engagement process.

Rio Tinto Copper & Diamonds chief executive Arnaud Soirat said: “This an important milestone for Resolution, with the future development of the project being shaped by years of engagement with the local community and extensive independent study by the US Forest Service.

“Achieving this significant milestone in the rigorous US permitting process allows us to continue progressing one of the world’s most significant untapped copper deposits towards development.

“Resolution has the potential to supply up to 25 per cent of the United States’ copper demand and complements Rio Tinto’s other copper projects.”

In April 2019, Rio Tinto has approved additional investment of $302m (£249.8m) in the Resolution Copper project.

The additional investment will be used to fund further drilling, ore-body studies, infrastructure improvements and permitting activities at the project, the firm said.

In addition to creating several thousand direct and indirect jobs in the Pioneer Mining District of Arizona, the Resolution Copper project has capacity to supply nearly 25% of the copper demand in the US once fully operational.