JOHANNESBURG (miningweekly.com) – Gold-miner Harmony Gold said on Thursday that it had halted production at its Joel North shaft in South Africa's Free State province until next month, while it makes modifications to the shaft bottom.

Harmony's CEO Graham Briggs said that Joel's gold production for the June 2010 quarter would be marginally affected by the shutdown, but that the shaft's September quarter production could possibly be halved.

"However, we have teams working around the clock to resolve this situation as soon as possible," he added.

Harmony expected that the shaft would be operating again in August, once repairs to the shaft bottom had been completed.

The employees at Joel had also been sent on leave and would return to work on August 10.

Briggs explained that the production focus at its Joel mine has over time been shifting to the deeper portions of the mine, at about 1 400 m below the surface. "However, the North Shaft was never fully equipped for production and we have therefore made extensive changes to the bottom of the shaft arrangements."

Modifications to the shaft included: the changing of the winder from sinking to production mode, attaching bigger skips, ensuring that emergency egress was available and raise-boring the lift shaft from 121-level to the 129-level.

However, operations at the shaft had to be halted to complete the bottom of the shaft spillage arrangements.

Meanwhile, Briggs said that the Joel plant would be processing waste to maximise gold production.

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