Chile’s Codelco, the world’s largest copper producer, has extended mining at its century-old open pit Chuquicamata mine for an extra year as the operation has yielded more than 30,000 tonnes of additional fine copper so far this year.
The state-owned miner shut the open pit section of Chuquicamata in 2018, and transitioned operations to underground block cave mining last year.
New technologies, however, made Codelco rethink the decision. The copper giant decided then to continue exploiting the pit until December this year.
The Santiago-based company has changed its mind again. It now expects the more than 1,100 metres-deep section of “Chuqui” — as locals call it — to keep running into 2021.
“We have promoted and achieved new ways of operating that have resulted, in the case of Chuquicamata, in a team that adapted to changes and sought continuous improvement,” executive president Octavio Araneda said in the media statement.
Araneda said ramp-up of the underground section continued to move forward according to schedule. The company had previously noted that a $5.6 billion-switch to underground cave mining from open pit was part of its 10-year, $39 billion overhaul of its core assets.
The underground operation will add at least 40 years to Chuquicamata’s life. It will also allow the copper giant to keep up production rates, despite falling ore grades and increasing costs at its operations.
Codelco, which hands over all of its profits to the state, holds vast copper deposits, accounting for 10% of the world’s known proven and probable reserves and about 11% of the global annual copper output with 1.6 million tonnes of production in 2019.
The mining company’s sprawling deposits, scattered across central and northern Chile, have continued to operate through the disruptions of covid-19 with reduced staff.