"The fire in the pit started on February 9th. I know it has been frustrating for the people of Morwell. It has been frustrating for the firefighters and their support team. But it has also been frustrating and disappointing that this fire was deliberately lit," Commissioner Craig Lapsley said.
Commissioner Lapsley says fire authorities have 85 per cent of the blaze under control.
A wind change that came through on Wednesday morning increased fire activity, setting back fire fighting efforts.
The wind once again pushed smoke over the Morwell township, leading the EPA to issue a high level smoke advisory.
But as the wider Gippsland fire crisis entered its 50th day, there was hope that the mine fire might be extinguished by the weekend
"We are not there but we are close," Fire Services Commissioner Craig Lapsley told reporters in Morwell.
"We would like to think that over the weekend we would be able to say that this fire is out, but it's too early to say that."
Incident controller Bob Barry said Wednesday had been a difficult day for crews with a wind change setting back the fire fight.
"Today we could step backward a little bit, hopefully not too far," he said.
A small grassfire broke out on Tuesday evening, near the Hazelwood power station, but it was quickly extinguished.
"The threat to the actual power station itself has reduced considerably, but we will continue our presence there to make sure we get through the whole day without any escapes," Mr Barry said.
A plan is now being developed for the clean-up of ash-covered homes, Mr Lapsley said.
Many people have left the area, with those over 65 years, preschool-aged children, pregnant women and anyone with a pre-existing heart or lung condition advised last Friday to temporarily relocate out of Morwell South, the area close to the mine.
Mr Lapsley said there was interest from firefighters across the world about how crews were managing the open cut mine fire.
Fires have been burning in Gippsland since mid-January, when dry lightning sparked blazes in East Gippsland during a record heatwave.
The Morwell fire began on February 9 when a deliberately-lit blaze spotted into the Hazelwood mine.
