The bomb dug up in a Bulli backyard was a World War II high-explosive mortar, that was most-likely made in an Australian factory.
The discovery of a British 3-inch HE (high explosive) Stokes Mortar at an Organs Road home on Sunday, September 10 ignited a full-scale emergency, with the road cordoned off and emergency services scrambling to the scene.
"I hit it pretty hard with the shovel, accidentally," plumber Elliott Doughty said.
The tradie only purchased the house in March 2023, and was undertaking renovations when he accidentally dug up the bomb.
"I've cut out the bathroom slab and I've gone down through there to do all the drainage. As I kept going down I ended up finding what I thought was a bomb. It looked like one and it turned out it was, and that was pretty scary," he told ABC.
He then pulled it out of the hole and held it with both hands.
"I was just mucking around having a bit of a laugh, and I said 'I think I've just found a bomb'," he said.
"I ended up giving it a bit of a wash to see exactly what it was.
"I don't know if I should have moved it or not, but nothing happened when I hit it with a shovel, thank God."
In hindsight, he admitted during the interview, "I probably shouldn't have been fiddling with it".
He called triple-0 and said he was surprised by all the "fuss" when police, the bomb squad and then Defence arrived at the quiet suburban street.
"We haven't been there very long, so I really didn't want to cause such a fuss. It was actually a little bit embarrassing because we had all the emergency services out there," he said.
Despite the embarrassment, Mr Doughty said he's glad he called triple-0 and he "wasn't going to put it in the red bin, that's for sure".
Department of Defence documents provided to the Illawarra Mercury show this type of unexploded ordnance is one of the most common found by civilians.
They have caused a number of fatalities as they're usually found on the ground's surface or shallow buried.
"The three-inch mortar bomb was produced in large quantities at various factories around Australia," documents state.
"All Australian infantry units (regular, reserve and militia) and numerous other military personnel fired the three-inch mortar at many live firing ranges throughout Australia and many were dumped at sea."
Six types of three-inch bombs were produced and they ranged from 3.2 kilograms to five kilograms.
They varied in length from 370-500 millimetres, and diametre from 81-82mm.
All Australian infantry units (regular, reserve and militia) and numerous other military personnel fired the three-inch mortar at many live firing ranges throughout Australia and many were dumped at sea.- Department of Defence documents
The main body is cast iron and may have one or more bands of colour. Red, yellow or green bands were most often used to denote hazardous munitions, however other colours may have been used or colours may have faded over time.
Defence warned the bombs may contain a sensitive fuse and explosive which can be easily detonated.
The degraded mortar found in Bull will now be disposed of "using routine measures", a Defence spokesman said.
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