Glencore has announced plans to close its Mount Isa Mines underground copper operations and copper concentrator in the second half of 2025.

Chief operating officer Sam Strohmayr said those operations and supporting services currently employed about 1200 people.

“It’s too early to put a figure on how many people may receive redundancies until we work through a process of speaking to each worker and discuss options around retention, redeployment, and retraining,” he said.

“Redundancies are the last resort and will be offered only when other options have been exhausted.

“Glencore will continue to invest in the long-term future of Mount Isa Mines, including the George Fisher Mine with a current life of mine to 2036, and our zinc-lead concentrator and lead smelter.

“We also expect the copper smelter and refinery to continue operating to 2030, subject to approval of additional capital investment.

“These are important strategic assets, not just for Glencore but for the North West Minerals Province and the future of Queensland’s critical minerals industry.”

The company’s Lady Loretta zinc mine, 140km north-west of Mount Isa, is also set to close in 2025.

The Mount Isa Mines underground copper operations include the Enterprise, X41 and Black Rock mines.

Low grades, ageing infrastructure

Glencore said it had conducted a range of studies and reviews seeking to further extend the life of the underground copper mines.

The studies revealed that the remaining mineral resources were not economically viable due to low ore grades and areas where, due to geological conditions, safe extraction can’t be achieved using current technology.

This, coupled with ageing infrastructure, meant they had reached the end of mine life, Glencore said.

Mr Strohmayr said Glencore knew the decision to close the Mount Isa copper mines would be disappointing for employees, suppliers, and the Mount Isa community.

“The reality of mining is that mines have a beginning, middle and end,” he said.

“And unfortunately, after 60 years of operation, Mount Isa’s underground copper operations have now reached that end.

“We want to give our people as much time as possible to consider the best options for them and their families, which is why we are notifying our workers and the community almost two years before these mines close.

“Our focus over the coming months will be to work closely with our people and contractors, our suppliers, and the Mount Isa community to provide support as we move towards closure of these assets.”