Leonard James Ruddell was fired by mine management in June for deceptively providing a cold urine sample in the previous month during a random drug test, with a second test confirming a “non-negative” result for the presence of THC.

He was also deemed to have dishonestly answered questions put forward by the drug and alcohol tester.

While the D&A policy at the mine encourages counselling and rehabilitation for first-time offenders, deliberately falsifying a sample, whether by providing someone else’s urine as a sample or by placing additives in the testing cup, can trigger immediate dismissal.

Yet the Construction Forestry Mining and Energy Union decided there was a case for unfair dismissal due to a breach in the chain of custody procedures.

But Ruddell had also given evidence that he had used an illicit drug on the Saturday night prior to the second test.

Fair Work Australia Commissioner Alastair Macdonald upheld the dismissal as fair because a false urine sample was provided.

But he was not impressed with false statements put forward by the worker.

“The applicant was willing to try and deceive the respondent where important safety consequences may result .... he had put his own recreation ahead of the safety of the people around him and himself,” Macdonald said.