By Gav Ross
A GAPING 15m hole has appeared in the grounds of one of Wonthaggi’s historic mine reserves following a sudden shaft collapse last week.
Luckily, no one was in the area at the time the earth gave way.
The sink hole is located directly in front of the beautifully derelict Number 5 Brace building in the Central Area, just west of Wonthaggi Hospital.
Measuring 8m wide, the area has been fenced off with a huge perimeter, ensuring no access while geotechnical officers continue to evaluate the area.
Parks Victoria team leader Brian Martin said the area was in a different part of town to the popular State Coal Mine visitor site.
“The hole has been fenced off temporarily and the current fence around the derelict Number 5 Brace was extended to include the hole,” Mr Martin said.
It’s a reminder that many parts of the town sit on top of old mine shafts but authorities have been quick to reassure local residents of their safety.
“I would also like to reassure people that this is not in the residential area of town so will not affect their properties,” he said.
“Parks Victoria will be seeking geotechnical advice regarding the site to identify the next steps.
“In the meantime, visitor safety is our top priority and we ask people to visit other areas in the park,” Mr Martin said.
Friends of the State Coal Mine volunteer and former councillor, John Fleming, said shaft collapses such as this one are very rare, and people shouldn’t be concerned their house might randomly be swallowed up.
“The one by Number 5 brace was capped when it was originally closed and it sounds like that has failed,” he explained.
“Shafts such as this are very deep but they’re already quite blocked up because when the mining finished, people would drop skips down there and stone and all sorts of stuff.
“I don’t think people should be particularly concerned about it happening anywhere else.
“There are parts of Wonthaggi where there are tunnels under the ground, but they’re 300ft down and even if they collapsed they wouldn’t disturb the surface.”
State Coal Mine manager, Braxton Laine, said the new hole will be recapped once investigations are complete.
“We’ve engaged experts to inspect the site and give us options of the best way to recap,” he said.
“What seems to have happened is that the surrounding banks have fallen into it, possibly caused by water erosion.
“The main thing is we want to ensure public safety is taken into account.”
Mr Laine said the last similar “slippage” occurred in the Central Area back in the 1970s.
The last one before that was believed to have occurred in South Dudley in the 1920s.