Rio Tinto has revealed an investment of $918m in its Kennecott copper mine near Salt Lake City, Utah, US to bolster copper supply in the country.

The company aims to increase the copper supply by ramping up production from underground mining as well as enhancing the health of key assets.

Rio Tinto will invest $498m in underground development and infrastructure for an area called the North Rim Skarn (NRS).

The North Rim Skarn area is scheduled to start production in 2024, with a ramp up expected over two years. It is projected to produce about 250,000 tonnes of additional mined copper over the coming 10 years in conjunction with open cut operations.

Besides, the mining group has invested $300m to rebuild the smelter at the Kennecott copper mine.

The rebuild, which is said to be the largest in Kennecott’s history, began last month.

Furthermore, Rio Tinto is investing $120m to renovate the refinery tank house structure as well as update Kennecott’s molybdenum flotation circuit with an advanced and fully automated system.

The upgradation is aimed at enabling the Kennecott copper mine to continue to deliver a high-quality product to customers, said the mining major.

Rio Tinto copper chief operating officer Clayton Walker said: “We are investing to build a world class underground mine at Kennecott and strengthen our processing facilities, to meet the growing demand for copper in the United States, a key material for domestic manufacturing and the energy transition.

“This investment will position Kennecott to continue the strong contribution it has made as part of the Salt Lake Valley community for 120 years, injecting about $1.5 billion annually to the local Utah economy.”

In September 2022, Rio Tinto sanctioned an investment of $55m to begin underground mining in an area known as the Lower Commercial Skarn (LCS) at the Kennecott copper mine.

The underground production within LCS commenced in February 2023. It is anticipated to deliver a total of about 30,000 tonnes of additional mined copper through the period to 2027.