The Dean's Gap bush fire, heading toward the former military site, is one of more than 100 fires burning across the state spurred by high temperatures and fierce winds, the Australian Broadcasting Corp. reported Thursday.
The former military site at the Tianjara plateau was used by the Australian Army as a practice bombing range until the mid-1970s and still contains unexploded bombs scattered throughout the area.
"We can't do any water-bombing with aircraft or something like that in case the weight of the water when it hits the ground sets off any unexploded ordnance," said Brett Loughlin of the Rural Fire Service.
"So it's a total no-fly zone and that will mean [if] the fire gets into that area, there's nothing we can do for it except wait for it on the other side," he added.
Loughlin said firefighters have bulldozed containment lines and used a special gel to prevent the fire from entering the range.
In recent weeks, bush fires have consumed acres of pastureland and burned homes from Queensland in the north to Tasmania in the south.
Cooler conditions Thursday could help contain some of the blazes, though higher temperatures and winds are expected Friday, the Australian Broadcasting Corp. said.