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More than 150 workers at the Cadia goldmine in regional New South Wales were evacuated after a nearby 4.5-magnitude earthquake on Tuesday evening, according to an internal company memo.

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

The quake’s epicentre was just 3km from the Newmont Cadia goldmine tailings dam, which partially collapsed in 2018. Effects of the quake were felt hundreds of kilometres away.

The quake hit at 8.19pm on Tuesday at a depth of 5km about 30km south-west of Orange in central west NSW.

An internal Newmont announcement sent to Cadia goldmine staff, seen by Guardian Australia, said 153 people who were working underground “are accounted for, and were progressively returned safely to the surface, and have been debriefed”.

“Personnel underground moved quickly and appropriately to refuge chambers,” the announcement said.

“Mine rescue teams worked through a structured re-entry and rescue plan.”

The announcement said the earthquake occurred to the east of the underground mine and was felt across the central west.

“Safety and the wellbeing of our people remain the top priority,” the announcement said.

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

The announcement acknowledged the event “may be unsettling for people. Please look out for one another, speak to your leader” and said a support service was available if needed.

The Blayney shire mayor, Bruce Reynolds, who lives about 12km from the epicentre, told Australian Associated Press his biggest concern when the quake occurred was the underground workers at the Cadia mine.

The quake “was like an explosion under the house,” Reynolds said.

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

“We’d just closed the tavern and were counting the takings and the place just shook like a truck was coming through it,” he said.

“It was crazy. Windows rattling, wine glasses rattling in the hotel.

“We had one once before out near the mine but that one last night was crazy.”

He said everyone at the tavern was alright and there had been no damage.

“The force coming from the mine side, the western side, it was like the pub leant one way and then came back the other,” he said.

The NSW premier, Chris Minns, said the government had no information to suggest the earthquake was linked to mining activity.

“We don’t believe it’s linked, or I’ve been given no information that it has been linked,” he said.

“I was briefed about it late last night, and there were evacuation protocols that were put in place for miners, but we’ll take a watching brief, and if we get any new or extra information we’ll obviously let the public know about it.”

Dr Phil Cummins, senior seismologist at Geoscience Australia, said the national seismic network used to locate earthquakes had “a fair bit of uncertainty associated with those locations” in the central west. He said this made it “very difficult to determine whether this [earthquake] was right in the mine or some distance from the mine”.

The uncertainty in the network also made it difficult to determine whether the earthquake was linked to mining, Cummins said.

“Certainly any triggering effect that might have been caused by mining activity would be very difficult to determine with the network that we have,” he said.

“You really need to have very intense deployments over an extended period of time to really determine that kind of triggering mechanism.”

A Newmont spokesperson said “safety procedures functioned effectively, and all underground personnel were accounted for and progressively returned above ground. There have been no reported injuries”.

“The safety and wellbeing of our people remains our highest priority. Underground operations have been paused while specialist teams undertake inspections and assessments,” they said.

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

Cummins said Geoscience Australia had received almost 2,300 reports of tremors and the earthquake had been felt as far away as Batemans Bay and Wagga Wagga. He said he would not be surprised if one or more aftershocks occurred, but these were generally expected to be at least one magnitude unit lower than the original quake – meaning any aftershock was expected to be 3.5 or lower.

He said the second largest earthquake recorded in the area had been a magnitude 4.3 in 2017, with other smaller earthquakes occurring in past decades.

Additional reporting by Penry Buckley and Australian Associated Press