A miner who worked the night before a fatal mud rush at Tasmania's Mount Lyell mine has told an inquest he had concerns about the area beforehand.
Michael 'Digger' Welsh, 53, was crushed by a sudden inundation of mud at Queenstown's Mt Lyell mine in January 2014.
A coronial inquest into the three deaths on Tuesday heard from production shift boss Leigh Johnstone, who worked at the mine in the days before Mr Welsh's death.
Mr Johnstone said he had "concerns" over the area - TD14.
The area's safety rating was increased from low to medium, the inquest heard.
Shift supervisor David Woolley said he inspected the area of the mine with Mr Welsh, who was an experienced bogger driver, the morning of his death.
Mr Woolley said both he and Mr Welsh thought the medium risk rating was too high as the area looked "firm" and "settled".
Mr Welsh died less than 20 minutes after that inspection.
He had radioed to a supervisor minutes before his death saying he'd almost finished work on the area.
The inquest heard evidence of the emergency radio call that went out less than seven minutes later: "Emergency, emergency. There's been a mud rush and I can't find Digger."
Operations at the mine were suspended soon after Mr Welsh's death.
The incident came a month after Craig Gleeson, 45, and Alistair Lucas, 25, died at the same mine when the wood platform they were working on collapsed.
Jason Retallick, a project manager for underground contractors Barminco, inspected parts of the mine in the week leading up to the fatal mud rush.
"(It was) hard to predict from what I saw," he said.
"There's no thought that crossed my mind that there was a problem there.
"There was no indication that it would slump like that."
The two-and-a-half week inquest before Coroner Simon Cooper resumes on Wednesday.