San Manuel: creating new life for an Arizona copper icon

Across North America, BHP's Legacy Assets team cares for more than two dozen former mine sites in Canada and the United States. These are the places where mining began generations ago and where our responsibility does not end at closure. Every day, our teams manage water and tailings, monitor the environment, and work alongside communities and Indigenous partners. 

Increasingly, this careful stewardship is also creating an opportunity to unlock new value from historical sites through partnerships, redevelopment, and, in some cases, a return to production. On 6 October 2026, BHP completed the sale of its historic San Manuel mine in Pinal County, Arizona, to Faraday Copper. Under Faraday’s operatorship, San Manuel will begin its next chapter. Faraday plans to redevelop the site alongside its neighbouring Copper Creek project, creating a new copper complex in the United States.

San Manuel's story began in the rugged hills of Pinal County, Arizona, where copper was first identified in 1879. It would take more than sixty years to reveal the true scale of what lay beneath the desert with a discovery in 1942 which uncovered one of the largest porphyry copper deposits ever found in North America.

Production began in 1955 under the ownership of Magma Copper, and San Manuel quickly grew into a cornerstone of American copper mining. Over nearly five decades, San Manuel and its neighbouring Kalamazoo orebody yielded an extraordinary 4.65 million tons of copper, along with significant volumes of molybdenum, silver and gold.

Like many mines of its era, San Manuel's story shifted with global copper markets. Sustained low prices in the late 1990s led to the suspension of underground mining in 1999, and the site was closed in 2003. Since this time, San Manuel has been carefully maintained, its water managed, its land monitored, and its potential preserved.

That potential is what drew Faraday Copper to San Manuel. With the transaction now complete, ownership and operatorship of San Manuel have transferred to Faraday, and BHP holds a strategic equity position of approximately 30% in the company. It is a structure that reflects how we are thinking creatively about unlocking value across our portfolio. Sometimes the best way to advance an opportunity is not to develop it alone, but to back an operator who is best placed to take it forward. Faraday will now lead future studies, permitting and stakeholder engagement as it works to define a path to production, combining San Manuel's brownfield advantages with Copper Creek's resource base to help meet growing demand for domestically produced copper.

San Manuel’s next chapter now begins—building on its proud history and creating new potential for the future.