NSW earthquake: gold miners fled to underground refuge chambers when 4.5-magnitude quake hit Orange | Earthquakes

More than 150 workers have been evacuated from the Cadia gold mine in western NSW following a nearby magnitude 4.5 earthquake on Tuesday evening, according to an internal statement.

The mine has suspended all underground operations pending a safety assessment.

The epicenter of the earthquake was just 3 kilometers away from the Newmont Cadia gold mine tailings dam, which partially collapsed in 2018. The effects of the earthquake were felt from hundreds of kilometers away.

The earthquake occurred at 8.19pm on Tuesday, about 30 kilometers southwest of Orange in central west NSW, at a depth of 5 kilometres.

An internal Newmont memo sent to Cadia gold mine staff, seen by Guardian Australia, said 153 people working underground had been “identified, gradually brought safely to the surface and interrogated”.

“Personnel underground were quickly and appropriately moved to shelter rooms,” the announcement said.

“Mine rescue teams worked out a structured reentry and rescue plan.”

The announcement stated that the earthquake occurred east of the underground mine and was also felt in the midwest.

“The safety and well-being of our people remains a top priority,” the announcement said.

“We are working on a structured process to develop a mine recovery plan.”

The announcement acknowledged that the incident “may be distressing for people” and said a support service was available if needed.

John Clemens, owner of Forest Reefs Tavern, about a 20-minute drive from the mine site, said they closed in the evening when they felt the earthquake.

“We had just closed the pub and were counting the winnings and the place was shaking like a truck was going through it,” he said.

“It was crazy. Hotel windows rattled, wine glasses clinked.

“We’ve found one near the mine before, but that one last night was crazy.”

He said everyone in the pub was okay and there was no damage.

“The force coming from the mine side, from the west side, was as if the bar was bending to one side and then coming back to the other side,” he said.

NSW premier Chris Minns said the government had no information that the earthquake was linked to mining activities.

“We don’t believe this is related, nor have I been given any information that it is connected,” he said.

“I was briefed on this late last night and evacuation protocols for miners had been put in place, but we will have a monitoring briefing and will of course notify the public if we receive any new or additional information.”

A Newmont spokesman said “safety procedures worked effectively and all underground personnel were counted and phased back above ground. No injuries were reported.”

Officials said, “The safety and well-being of our people remains our top priority. Underground operations have been stopped while expert teams conduct inspections and evaluations.”

“The company will provide an update on material production impacts, if any.”

Geoscience Australia has received more than 2,000 reports of tremors in the region; a senior seismologist said they were weak to light and could be felt as far as hundreds of kilometers southeast of Batemans Bay.

Dr Phil Cummins said only five earthquakes of a similar scale had been recorded within 50 kilometers of the earthquake zone since 1977, with the previous one measuring 4.3 in 2017. He said it was “a major earthquake for this region.”

Cummins expected aftershocks would likely be much milder and felt over a smaller area.

Additional reporting by Penry Buckley and Australian Associated Press