Peabody Energy reduced production at the Queensland mine by about 1.5 million tonnes per annum in August while Thiess was criticised by union officials the following month for its decision to inform more than 100 Burton workers of their redundancy via text message.

According to Mackay Daily Mercury, “vice president” Adam Hatcher and field supervisor Allan Baker were both fired by Thiess on May 8.

“Both men had clean employment histories and between them they would have received around $250,000 in any redundancy package,” the newspaper reported.

The tribunal heard that the men were terminated after Baker left the minesite only hours into an overnight shift on March 27 to attend a medical appointment.

While Baker’s legal team argued that he had suitable permission to leave his post early, the defence denied this was the case and said he left at a critical time.

Meanwhile, Hatcher was terminated for breach of trust, with Thiess arguing he was not truthful when asked about the time that Baker left the site.

A Thiess witness to the case, a superintendent, admitted he had since been fired for misuse of a company credit card while under cross examination.

Both Baker and Hatcher have 26 years of employment with Thiess between them.