Pike River Coal says it is making significant progress on it plans to re-enter the mine where the bodies of 29 men remain.
The latest efforts have centred on installing a vent at the mine entry to get fresh air into the entry tunnel up to the second entry point 25 metres inside.
Briefing reporters at the mine, statutory manager Steve Ellis said this ventilation unit was crucial to the plan to gradually re-ventilate the entry tunnel.
He said he hoped to start work on creating a remote seal just before the rockfall by mid-November and to have completed re-entry to the tunnel by Christmas.
The sale of the mine could also be completed by Christmas, with firm bids due in by the end of September.