The 80 million tonne per annum mine will be the most technically advanced iron ore mine in Western Australia.

The South Flank project leveraged off existing infrastructure at Mining Area C and involved construction of an 80Mtpa crushing and screening plant, an overland conveyor system, stockyard and train loading facilities, procurement of a new mining fleet and substantial mine development and pre-strip work. 

Together with the existing Mining Area C, it will form the largest operating iron ore hub in the world - producing 145Mtpa of iron ore. 

"South Flank is Australia's largest new iron ore mine in over 50 years and is on time and on budget," BHP President Minerals Australia Edgar Basto said.

"South Flank's high quality ore will increase WAIO's average iron ore grade from 61 to 62%, and the overall proportion of lump from 25 to 30-33%."

The project created more than 9000 direct and indirect jobs during construction, and will employ more than 600 people during operations.

The operational workforce is 40% female and 15% indigenous.

"South Flank is on Banjima country, and this milestone would not have been possible without their support and collaboration over many years," Basto said.

"We are proud of our longstanding partnership and strong working relationship with the Banjima people, and we thank them for their vital contribution to this success."

More than A$4.6 billion of works have been awarded for South Flank with 78% awarded to Australian businesses, including 41% to Western Australian businesses, and 37% committed in the Pilbara region. 

South Flank has a competitive capital intensity of US$45/t - approximately half of BHP's last major iron ore project, Jimblebar.

Western Australian premier Mark McGowan and federal resources minister Keith Pitt congratulated BHP on the milestone.

Pitt made his first visit to the Pilbara this week, visiting Jimblebar.

"This is a major project that is creating thousands of jobs and again shows why the resources sector is so important to our national economy," he said.

"Establishing Australia's biggest iron ore project in half a century is a significant vote of confidence in the industry's future and its long-term benefits to Australia."

Chamber of Minerals and Energy of WA CEO Paul Everingham said South Flank showcased many aspects of best practice and highlighted the sector's overriding commitment to working safer, cleaner and smarter.

"The modular construction methods used at South Flank reduced exposure to some of the higher risk construction activities that would traditionally have been involved in a major project like this," he said.

"South Flank has also been designed from the start with a focus on technology and the use of autonomous mining equipment, including haul trucks.

"And the high-quality ore it will produce will provide for a reduction in emissions in the steelmaking processes undertaken by BHP customers."