Major Newmont mine Cadia halted after earthquake: report

Underground operations at Newmont’s (NYSE, ASX: NEM) Cadia gold mine in Australia -– one of the country’s largest mining operations — have been suspended for the second time in nine weeks after two earthquakes rocked New South Wales Friday, the Australian Broadcasting Corp. reported.

A magnitude-3.4 quake was recorded Friday at about 5:45 a.m. local time within the Cadia mine site, the ABC reported. This followed a magnitude-3.2 tremor, which was recorded at about 3:20 a.m. Cadia is located about 250 km west of Sydney.

All underground personnel were safely returned to the surface, and there were no reported injuries, the ABC cited Newmont as saying in a statement.

The second quake occurred 1 km underground, the ABC said. Inspections are being carried out on the site.

Spokespeople for Newmont didn’t immediately respond Friday to an e-mail from The Northern Miner seeking comment.

April tremor

Cadia accounts for about 11% of Newmont’s net asset value, according to RBC Capital Markets. Newmont gained full control of the operation in November 2023 when it completed the $19 billion acquisition of Newcrest Mining.

Friday’s earthquakes follow a 4.5-magnitude event at Cadia on April 14, which led Newmont to suspend underground mining for about five weeks. No significant damages were reported.

Newmont subsequently disclosed a five-week rehabilitation process to reach 80% of Cadia’s capacity, RBC mining analyst Josh Wolfson said Friday in a note. “Full normalization” was projected for the third quarter, he added.

“Seismic issues at Cadia represent a safety risk and operating uncertainty, potentially impacting production targets or introducing additional regulatory risks,” Wolfson wrote.

Full control

Cadia produced about 385,000 oz. of gold and about 82,000 tonnes of copper last year. The mine is approved to continue operations until 2031, though mineral resources have been identified for production up to at least 2048.

Commercial production at the Cadia East underground mine began in 2013 using large-scale panel caving methods.

Newmont shares fell 6.7% to A$143.47 on Friday in Australian Stock Exchange trading, valuing the company at about A$111 billion ($78 billion). The US stock markets were closed for the Juneteenth National Independence Day.