All mining at the massive Grasberg Mine in Indonesia will shift to underground operations by 2022.

Freeport Indonesia’s chief executive, Tony Wenas, told Reuters that the operations will gradually move away from all surface mining at the world’s second-largest copper mine. Freeport Indonesia is a unit of Freeport-McMoRan.

“By 2021, approximately 75 percent of our operations will be underground mining, with it reaching 100 percent by 2022,” said Wenas.

Reuters reported that Wenas said Freeport had returned to its normal production levels and would be producing 110 kt/d (121,000 stpd) of ore for 2020. This will rise to 160 kt (176,000 st) daily tonnes of ore for 2021 and 200 kt (220,000 st) for 2022, as the firm completes its transition to underground mining, he said.

Freeport last month had to cut its workforce at the Grasberg Mine after four workers died of COVID-19 amid rising infections of the new coronavirus in the area, including at the crew's living quarters.

Wenas said Freeport had developed testing facilities for the virus and had seen a 60 percent recovery for infected workers.