Coal mine workers at South32’s Dendrobium mine walked off the job this morning as part of week-long strike action.
Around 200 miners have stopped work, bringing the mine to a halt.
The strike comes after South32 and the CFMEU were unable to agree on the terms of a new enterprise agreement.
The agreements expired in April 2014 when BHP Billiton still owned the mine, which is managed by subsidiary Illawarra Coal.
South32 now owns Illawarra Coal and the Dendrobium, Appin and West Cliff coal mines after the BHP demerger in May.
CFMEU Mining and Energy Division South West District Vice President Bob Timbs said the main stumbling block is a security of employment clause which would protect permanent employment and provide future job opportunities for contract mine workers.
— Rob Morrison (@RMorrison9) August 14, 2015
The union claims that in recent years, BHP and now South32 have increasingly made use of lower paid labour hire and contractors to do work normally performed by permanent full time employees.
It says contractors can be paid around $500 per week less than full time employees and claims that most contractors employed in recent times do not have access to conditions such as annual leave, sick leave, redundancy pay and top up accident pay.
Illawarra Coal says it is disappointed workers have voted to take strike action.
"Disruptive industrial action by the CFMEU would create further uncertainty for the company, its employees and the broader community,” Illawarra Coal Asset President, Troy McDonald said.