Commissioner Bernie Riordan said the use of foul language in the workplace was "unfortunate but very commonplace", saying that Matthew Gosek, who brought unfair dismissal charges against the company,  and his associates "work in a coalmine, not a convent".

Gosek, who is a lodge president for the Construction Forestry Mining and Energy Union, is to be reinstated and receive partial back pay.

Commissioner Riordan said the use of inappropriate language had been condoned by the mine's owner South32 subsidiary Illawarra Coal "for at least five years".

South32 is appealing the decision and a hearing has been set down for November 30.

A South32 spokesman told Australia’s Mining Monthly: “We have filed an appeal against the decision, which included a request to stay on the enforcement of the outcomes. 

“As this matter is before the Fair Work Commission it would be inappropriate for us to discuss the details. 

“We do not tolerate any form of harassment or bullying and our values support a culture where we treat people fairly and respectfully.”

South32 CEO Graham Kerr addressed employees in a video last week, saying any form of harassment or bullying would not be tolerated.

"We are working hard to create an inclusive workplace where everyone feels comfortable and safe at work and can speak up without fear," Kerr said.