Mining giant BHP will create 120 new jobs at its Olympic Dam operation in South Australia's far north over the next year, in another sign the state's mining industry is enjoying a positive turnaround.

The company is in the process of expanding its copper and uranium mine underground, near Roxby Downs, and has said it plans to spend $600 million at the site this financial year.

The 120 positions are in addition to 350 new Olympic Dam jobs announced by BHP earlier this year.

South Australian Chamber of Mines and Energy (SACOME) chief executive Rebecca Knol said the new jobs were a sign of good things to come for the resources sector.

"It is an industry that has ups and downs, and we've just come out of a very flat period," she said.

"We've seen announcements by BHP, but also Oz Minerals, Iluka [and] Arrium ... so there's been a significant number [of jobs created] for regional South Australia in the past couple of months.

"This is a sign that we're heading into a very strong resources growth period."

Recruitment to begin at JOBEX

In August, OZ Minerals announced it had won approval from its board to begin mining copper and gold at its Carrapateena project near Port Augusta, creating about 500 ongoing jobs.

The new owner of the Whyalla steelworks — GFG Alliance's Liberty House — plans to invest up to US$1 billion in the steelworks and mining operation, to modernise facilities and expand production capacity.

Only two years ago, BHP slashed several hundred jobs from its Olympic Dam operation in response to "global challenges" in the resources sector.

"It was a commercial decision not to proceed [with an underground expansion] a couple of years ago which resulted in job losses, whereas now it's a decision to proceed with that underground expansion ... and that [means] the creation of a lot of jobs," Ms Knol said.

"The turnaround has been in commodity prices generally, and it is a cyclical industry.

"This is an exciting opportunity for ... young adults living in these regions to get really meaningful work that is well paid and increases their skill base."

BHP's Olympic Dam asset president Jacqui McGill said the recruitment process would begin today at the JOBEX expo in Adelaide.

"We have sustainable growth plans and we are investing to make the Olympic Dam operation modern and technologically advanced," Ms McGill said.

"It is a really exciting time to be part of the industry, and part of Olympic Dam, and we want people from truck drivers to technology professionals to engineers, and everything in between to join us."