On Friday, December 13, the Currowan fire continued to burn in a northerly direction and the Rural Fire Service (RFS) said it had the potential to reach Tianjara in the Moreton National Park.
The Morton National Park is closed, including the popular bushwalking area of Tianjara, where unexploded ordnance is believed to be present at former artillery training area.
The RFS said: "There is the potential for the fire to reach Tianjara Prohibited Area which contains substantial unexploded ordnance. This will limit suppression activities."
The out-of-control fire has burnt more than 84,000 hectares.
The RFS said fire activity on the eastern side on the Princes Highway has eased, however, active areas of fire continue to burn.
"Crews continue to implement containment strategies along the eastern and western sides of the fire," the RFS said.
"This will involve the construction of hard containment lines using heavy plant north towards Braidwood Road which may take up to three weeks.
The RFS said active fire may still be around Benandarah, Windywoppa, Currowan and other areas on the northern side of the Kings Hwy.
"The fire may occasionally flare up in areas of unburnt vegetation around Lake Tabourie, Bawley Point, Kioloa, Pretty Beach, Pebbly Beach, Depot Beach, Durras North, and South Durras," the RFS said.
Aircraft are working on the northern spread of the fire in inaccessible areas of Morton National Park.
The Princes Highway is open with reduced speed limits and the Kings Highway has remained closed between Nelligen and Braidwood due to falling trees, rocks and backburning operations.
For updates, visit the Rural Fire Service website (Fires Near Me).
For traffic updates, visit the Live Traffic website.