'Unexploded ordnance' dug up in Canberra nature reserve, and not for the first time

Hitting a rock with a lawn mower might create some cringing, and an old plastic bag a lot of swearing as you extract disintegrating shreds of it from around the blades. But high on the list of things you definitely do not want to accidentally run over would be a 76-mm High Explosive Projectile – in other words, an anti-tank shell fired from Allied guns towards the end of World War II.

Just such a formidable weapon was discovered clearing works at the West Majura Grasslands Reserve, formerly a test site for the Australian Army.

The ACT Government wants to designate the land for conservation and a safe habitat for endangered species like the Grassland Earless Dragon and Golden Sun Moth. But before they can get the mower and weed spray out, they have a problem – this quiet paddock is also a literal minefield.

During the first half of the 20th century, Majura and Ainslie were used as live military firing ranges. The Army would test new weaponry and also train cadets in how to use it. The bombs that went off left shrapnel, while those that didn’t … well, were still there, buried.

Over the years, this has led to the finding of “unexploded ordnance”.

In July 2011, a member of the public stumbled across some near the Defence offices at Campbell Park, prompting a search that turned out eight unexploded mortar bombs.

More recently, in February last year, two more three-inch bombs were uncovered, and Defence staff were told to “limit their movements in and outside of the Campbell offices” until the shells could be safely destroyed.

Further afield, a 2019 Construction Environmental Management Plan for future parts of the suburb of Whitlam in the Molonglo Valley noted “areas with potential unexploded ordnances”.

The West Majura Grasslands Reserve was closed on 9 October 2023 for what was expected to be up to six months of searching for and disarming unexploded ordnance, during which the public would be barred from entry, with penalties for trespassing.

On 12 January, the warning signs finally came down and the site was declared safe to visit.

“Five unexploded ordnances were discovered and removed from the West Majura Grasslands Reserve during the closure,” ACT Parks and Conservation Service executive branch manager Stephen Alegria said.

“Explosive ordnance waste was also discovered, including shrapnel, mortar tails and fuses from the exploded rounds. This waste was inspected to ensure it was free from explosives and taken to metal recyclers.”

Acting senior director of parks and partnerships Michaela Watts added that 1600 anomalies were uncovered across the reserve by a mix of hand-held and tow-along metal detectors.

“We also found some pretty normal agricultural debris from before and after it was used as a range,” she said.

But when the contractors came across the three three-inch mortars, smoke mortar and the 76 mm projectile – all mostly intact – the finds were treated “as if they could go off”.

A 450-metre-wide exclusion zone was marked out, the Campbell Park offices evacuated, and all the “relevant authorities” were contacted during “controlled demolitions”. The objects were sealed down with firing pans and detonated in controlled explosions.

“Making them blow up wasn’t very exciting, really – you think you’d get a bit of boom, but these guys do it all the time, so it was more like a dull thud, and that was it – it was done,” Ms Watts said.

Urban legends suggest larger, more sinister equipment was disposed of on the site, but the government’s team “didn’t find any evidence”.

Today, the only live military firing range exists in the Majura Training Area, 3.6 hectares of grassland and pine forest adjacent to Pialligo Avenue and Sutton Road near Queanbeyan.

Every few months, the Australian Defence Force will warn nearby residents to “not be alarmed if they see military personnel carrying weapons”.

“Residents of nearby areas may see explosions, hear the noise they generate or feel the vibrations associated with them,” the alerts read.

Signs that read “Military target area” and “do not touch anything – it may kill you” help ward off would-be trespassers too.

Now they’re confident the land is cleared, Ms Watts said ACT Parks contractors will move onto West Majura Grasslands Reserve and “improve the habitat degradation there”.

“We’ll look at treating weeds and biomass control and what sort of birds and critters we have there so we can restore the grasslands habitat.”

Defence says if you come across a ‘suspicious item’ that may be unexploded ordnance, do not touch or disturb it. Contact ACT Policing on 131 444 and they will arrange for military experts to attend and dispose of it.