The cause of the big Queenstown tyre fire is being treated as suspicious, Copper Mines of Tasmania says.
The blaze in a gully near the Mount Lyell mine broke out last night and the Tasmania Fire Service expects it to last for some days, with residents earlier urged to stay in their homes and close windows and doors.
Mine owner Copper Mines of Tasmania said it was working with the TFS to extinguish the fire in a stockpile of old tyres at the abandoned Royal Tharsis mine site.
"The Tasmania Fire Service has done a fantastic job to knock down the blaze and stop the fire spreading but, unfortunately, it is likely to smoulder for some days," CMT acting general manager Clint Mayes said.
He said the prevailing winds were blowing smoke away from Queenstown and the Environment Protection Authority would monitor air conditions to ensure public safety.
"The cause of the blaze has not yet been determined, but Tasmania Police and the TFS are treating it as suspicious," CMT said
The Royal Tharsis open cut mine stopped operating in the early 1970s.
It is about kilometre from CMT's mine.
CMT estimated there were about 1000 large truck and loader tyres and about 500 light vehicle tyres stored in the area.
Mr Mayes said the blaze had not affected mine infrastructure and would have no impact on the mine sale process or CMT's future operation.