A dozen former executives from Linc Energy will face tricky questions over serious contamination at a gas plant on Queensland's Darling Downs.

Linc Energy will stand trial on five charges of wilfully causing environmental harm at the controversial underground coal gasification (UCG) plant near Chinchilla.

Linc founder and former chief, Peter Bond, has been handed an Environmental Protection Order ordering him to decommission the UCG plant.

He must also initiate the rehabilitation of soil and dams at the site.

The 12 other former Linc Energy executives have reportedly received letters from the Queensland Environment Department and will be interviewed as part of the ongoing investigation.

“These matters are handled by the state's environment regulator,” according to Queensland Environment Minister Steven Miles.

“I'm aware that the local community has been very concerned by the events they saw unfold at the Linc site and a thorough investigation is appropriate.”

Linc Energy will be liquidated after a vote by creditors earlier this year.

It is a big fall from grace for a company once worth $2 billion.

Former Linc employees are among hundreds of creditors owed close to $320 million, but the liquidator says they have businesses interested in buying Linc's assets, so everyone should receive what they are owed.