There is "no evidence" Linc Energy's operations near Chinchilla caused fracturing above the coal seam, allowing toxic gas and other contaminants to escape, the company's chief executive says.

The mining company is facing five counts of causing serious environmental harm for allegedly causing irreversible damage to valuable cropping land at its Underground Coal Gasification site near Chinchilla.

Last week the company submitted its final statement to a committal hearing, claiming "insufficient and unreliable" evidence means the case should not proceed to trial.

Following the submission, chief executive Craig Ricato spoke publicly about the matter for the first time.

"The evidence that they've put on simply doesn't prove the allegations that have been laid against us, and our position is, it doesn't prove the allegations because the allegations simply are not true," he said.

It has been alleged Linc Energy's operations caused fracturing above the coal seam, which allowed toxic gas and other contaminants to escape.

"There is no evidence of that. We operate the site, we don't have evidence of that and they've done their own drilling and they haven't produced evidence of that," Mr Ricato said.

Linc Energy suggested gas reportedly escaping could have come from one of the hundreds of wells drilled on the site.

"If there is any gas leaking to the surface, the most obvious connection would be through a well," he said.

Prosecution witnesses have recounted how former Linc workers reported seeing and smelling gas escaping and found high carbon monoxide readings in the area.

Details also surfaced of alarming health issues for workers.

Mr Ricato has labelled some of the claims as "outrageous".

"Some of the allegations that we've heard, that we directed people to drink milk and eat yoghurt, they're a little bit ridiculous to be honest and they're not really worth our time to try to defend something as outrageous as that," he said.

In its final submission Linc argues that because of "insufficient and unreliable evidence" the company should not be made to stand trial.

The Environment Department will make its final submission next week.

The Magistrate will then consider whether there is enough evidence to proceed to trial with a decision expected early in 2016.