Copper Mines of Tasmania pleaded guilty to one of two counts against it for failure to comply with a health and safety duty in the Burnie Magistrates Court on Monday.

The guilty plea related to the deaths of Alistair Lucas and Craig Gleeson, who died after a fall at the Mount Lyell mine in December 2013.

However, the company did not enter a plea on the second count.

That related to Michael Welsh’s death at the mine in January 2014, after a mud rush.

Former Mount Lyell mine manager Gerard Clyde appeared on  one count of failing to comply with the duties of a site officer. 

He did not plead, and was bailed to next appear for mention on October 17.

The charge against the company relating to Mr Welsh was also adjourned until that date for mention. 

Magistrate Tamara Jago adjourned the count to which the company pleaded guilty until November  9.

It is pushing towards three years since the deaths. 

Australian Workers’ Union representative Ian Drake said the miners’ families were frustrated by how long the court matters were taking.

CMT general manager, care and maintenance, Peter Walker said the guilty plea  followed discussions with the office of the director of public prosecutions.

Mr Lucas and Mr Gleeson had been working on a temporary wooden platform near the bottom of the mine’s main shaft when a linkage assembly fell onto the platform, causing it to break away.

Mr Walker said the company very much regretted the incident and had been in touch with the families of the two men to inform them of the plea, as well as with Mr Welsh’s family.

Mr Walker said the welfare of the families of the three men remained the company’s focus.

“It would have been our preference to have the court hearings for both matters heard simultaneously so as to manage, as far as possible, the impact on families and workmates,” he said.

“Unfortunately this has not been possible.

“We have been somewhat frustrated with the length of time it has taken for these matters to be finalised, but we also understand that these are complex matters that require careful consideration.”

The mine remains on care and maintenance due to weak copper prices.