A mine operated by Anglo American was evacuated with concerns over the atmosphere.
A mine operated by Anglo American was evacuated with concerns over the atmosphere.

BREAKING: Workers to re-enter evacuated CQ mine today

UPDATE 1.50PM: MINING giant Anglo American has confirmed workers will re-enter its Grasstree Mine this afternoon after they were evacuated yesterday due to concerns about atmospheric changes. 

About 200 workers were evacuated from the mine, near Middlemount.     

An Anglo spokeswoman said routine sampling in the course of standard operations detected the change.  

"The event was caused by drawing oxygen into a newly sealed area of the mine," she said. 

INITIAL 10AM: MINERS were evacuated from an underground mine yesterday after concerns about atmosphere changes.

Mine operator Anglo American confirmed an incident at its Grasstree Mine, which the company said involved a change in the underground environment behind a newly sealed longwall area.

"Based on our standard procedures, personnel were withdrawn from the underground environment as a precaution only," a company spokeswoman said.

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The spokeswoman said underground sampling showed different levels of oxidisation in the mine prompting the company to take the precaution to remove people from the site.

She said while the incident was being reported as "potentially explosive" there were no "triggers" in the area.

Despite reports the Queensland Mines Inspectorate was involved in the withdrawal of staff at Grasstree after an audit, the Department of Natural Resources and Mining said this was not accurate.

Work is underway to prepare for re-entry and return to normal operations.