The three month industrial dispute has seen management and contract labour step in and achieve better tonnages at the mine than the permanent workforce, according to some sources.

A spokesman for Glencore confirmed to Australia’s Mining Monthly that Glencore initiated a lockout of employees at Oaky North, which will remain in place until Friday 28 July.

“The action is in accordance with Fair Work Australia legislation and responds to the Construction Forestry Mining and Energy Union’s continuing campaign of strikes, workplace bans and limitations at Oaky North,” he said.

“The Oaky North CFMEU has so far taken in excess of 28,500 hours of industrial action as part of this campaign.

“Despite the CFMEU’s campaign, the mine is maintaining production and will continue to be operated by staff and trained personnel.”

As workers ended their legally protected industrial action following a 99% “No” vote on Glencore’s proposed workplace agreement, they attempted to return to work only to be met by company guards at the gate and refused entry to their own workplace, CFMEU district vice president Chris Brodsky said.

The proposed agreement would have stripped workers of several key legal entitlements, he said.

“We believe Glencore’s end game is to replace the permanent workforce with casual contractors ahead of their plans to shut the mine as a strategy for minimising their financial responsibilities to workers,” Brodsky said.

“This is a real David and Goliath battle at the moment. Glencore has had the local government come and remove the picket line.”

The deal Glencore is proposing would remove workers’ basic rights from their Enterprise Agreement including access to workplace representation in some cases, according to the CFMEU.

The union has offered a two year roll over of the existing agreement with a 0% pay increase.