Mount Isa's underground copper mine ceases production after 70 years

Australia Broadcast Center

7 days ago

The ground usually shakes twice a day in Mount Isa — it has done so for seven decades.
But today, the underground blasts won't happen.
It's a silence that marks the end of copper mining in one of the richest mineral deposits in the world.
The closure of Mount Isa Mines' underground copper operation, owned by Swiss multinational Glencore, has cost close to 500 direct jobs.
Mount Isa Mayor Peta McCrae said the mine loomed large in the city.
"It is ingrained in our psyche," she said.
"I don't think there's any other towns where it is actually built right around the mine."
Cr McCrae said the reality was yet to set in for many residents.
"I think it's going to take a couple of months for us to fully realise the impact of this," she said.
"We hear people are slowly moving away and it saddens us when we know that potentially there's still so much opportunity left here."
Historian and archivist Barry Merrick said the blasts felt by residents were caused by the detonation of explosives used to reach valuable metals like copper, zinc and silver.
They happened at 8am and 8pm sharp.
For residents the blasts were a daily ritual, but for visitors they were often a surprise.
Mount Isa resident Jenelle Robartson said "a huge one" went off one day while backpackers were visiting a local bottle shop.
"All the bottles were shaking on the walls clinking together and they both ducked under the counter and put their hands over their heads," she said.
"We all kind of had a bit of a giggle but then had to explain it was just the mines."
And a former ABC reporter once thought he had stumbled across a big story, after feeling a blast in his hotel during his first night in Mount Isa.
The 1.9-kilometre-deep copper mine has fed the smelter that sits beneath the city's candy-cane-striped smokestack for 70 years.
It was Australia's deepest underground copper mine and the country's third-largest producer of copper.
The mine is so big that if you joined the 900 kilometres of underground tunnels together, you could drive through them from Mount Isa to Townsville.
Mr Merrick said mine opened in 1924, but for it was mainly a lead, zinc and silver mine for its first 30 years.
Mr Merrick said it wasn't until World War II that the mine temporarily shifted its focus to copper at the request of the federal government to help with the war effort.
A surge on global copper demand in 1953 led the Mount Isa Mines to launch a dual-stream copper and lead-zinc-silver production, as well as commission a copper smelter — which is now burned into the city's skyline.
"From then on it was just boom time after boom time," Mr Merrick said.
"There was always expansion work, accommodation in town was next to impossible to get and the influx of people was everywhere."
By 1975, the mine had extracted 10 million tonnes of copper ore.
Mr Merrick said the closure was a reminder that the earth's minerals were a finite resource.
"It doesn't keep growing, if you take it out, nothing can replace it," he said.
The historian said copper mine's end was only a few years shy of what was predicted of its counterpart zinc, lead and silver mine back in 1929.
"The government geologist said at that point in time, Mount Isa would have a life of 100 years at the rate that they were extracting the ore," Mr Merrick said.
While copper production may have ceased, Glencore Metals Australia interim chief operating officer Troy Wilson said the mine's legacy would live on in Mount Isa.
"Mount Isa Mines, including Mount Isa Copper Operations, has a rich history and for generations, Australian miners have considering working at Mount Isa Mines a rite of passage," Mr Wilson said.
"It has been nothing short of remarkable and will be felt for years to come."