The vote – which was organised by the Construction Forestry Mining and Energy Union – clears the way for workers to strike or limit production with 72 hours’ notice as they seek to negotiate a new enterprise agreement with the Perth-based South 32.

The workers are concerned that a new enterprise agreement that will replace the agreement made with BHP Billiton will not include clauses that limit the use of casual labour.

It is expected that other Illawarra coal mines in South32 – Appin and West Cliff – will follow suit as their enterprise agreements expired last month.

South32 told that its Illawarra Coal subsidiary is committed to finalising a new enterprise agreement with its employees at the Dendrobium mine.

Illawarra Coal asset president Troy McDonald said: “Since late 2013, we have been working with employees and their representatives to develop a new enterprise agreement for mineworkers and trades employees at Dendrobium mine.

“As a sign of good faith to our employees, we have commenced for a six month period the pay increase that has been the subject of negotiations while discussions continue.

“Illawarra Coal looks forward to working with Dendrobium employees and their representatives to achieve a resolution, in this difficult economic environment for the coal industry, in the near future.”