Unexploded ordnance

The following advice may be useful to walkers planning to visit former military training areas.

In August 2014 the NPWS called a meeting of users of Morton National Park to discuss a new survey by the Department of Defence of unexploded ordnance in the former Tianjara Military Training Area in the Budawangs. The Defence and NPWS staff at the meeting provided information on assessing and minimising the risk of unexploded ordnance.

Walkers in former military training areas should be aware that:

  1. Metal fragments in a former military training area indicate that shells have landed nearby; Defence estimates that approximately 30% of projectiles do not detonate on impact.
  2. Military trainees sometimes targeted prominent rocky outcrops, such as Webbs Crown in the Budawangs. Prominences are more likely to attract bushwalkers seeking view points.
  3. Any disturbance of soil can increase risk. Putting in a tent peg or digging a toilet hole can make ordnance explode, as can heat seeping through the ground from a camp fire.
  4. According to Defence, if ordnance lands intact, its potential to detonate does not decrease over time.

On the other hand, walkers should also consider these factors:

  1. Defence reports that no-one in Australia has been killed or seriously injured by accidentally stepping on ordnance. All deaths and injuries have occurred when people have picked up and/or relocated ordnance.
  2. Where a serious bushfire has been through an area, it may have caused some ordnance to detonate harmlessly.
  3. The two dangerous shells found in the recent survey in the Budawangs were buried over a metre deep on fire trails. Vehicles had driven over them for decades without a problem.
  4. Unsanctioned off-track use of the restricted area has occurred for decades (eg a CBC walk to Webbs Crown in the late 1970s) with no reports of injury or death.
  5. Off-track bushwalkers tend to look where they put their feet, and to prefer open routes such as bare-rock leads.
  6. Risk mitigation strategies include use of fuel stoves instead of camp fires, using camp sites that look as though they have been used previously, pitching tents without using pegs, and digging toilet holes observantly.

August 2014

Unexploded ordnance on display, NPWS, Nowra

Unexploded ordnance on display at NPWS, Nowra