Expanding on Prominent Hill

The Prominent Hill Expansion Project, known as the PHOX Project, is an expansion of the existing owned copper mine and processing facility located 650km north-west of Adelaide.

Monadelphous has a long history working at Prominent Hill, having been part of the original construction back in 2007 – 2008 for the then owner Oxiana Limited.

The PHOX Project involves the sinking of a 1,300m deep shaft and construction of a 6.5 Mtpa materials handling system to transport ore from the underground mine to the surface coarse ore stockpile as the mine expands its underground operation.

In mid-September 2024, Monadelphous was awarded the detailed design, supply, fabrication and onsite construction of civil, structural, mechanical, piping, electrical and instrumentation works associated with the above ground materials handling system as well as the winder and winder building that manages the lifting of the ore up the 1,300m underground shaft.

The rapid deployment of an experienced project team was required to commence detailed engineering and fabrication works together with preparation to mobilise to site before the end of the year to commence site civil works.

The PHOX Project is of significance to Monadelphous as it forms part of our customer’s ambitious plan to expand its copper operations in South Australia by more than 50 per cent to more than 500,000 tonnes per year. The project continues our long relationship with our customer across Australia and provides the opportunity to be part of this exciting expansion plan for the copper business in South Australia.

The project has allowed us to bring together a team from multiple EC business units and geographical locations and is one of the first fully integrated packages since welcoming Melchor into the business - involving Inteforge for detailed engineering, supply, fabrication and delivery of steelwork; heavy lift for provision of lift engineering and heavy lift cranage; Melchor for delivery of civil construction works as well as our traditional SMPE&I delivery teams.

What is most pleasing is that the team drawn from the various business units and geographical locations, both within Australia and overseas, have worked together to become a cohesive integrated project team focussed on delivering for our customer.

Through the mobilisation process and early construction works the customer has commended the team on our professionalism, delivery focus, and clear commitment to the safety of our people.

Whilst works are in the early stages, with a peak labour force of approximately 150 not scheduled until July 2025, the team have set themselves up for success with the culture that has already been established on the Project.

There are a number of challenges to come, particularly with the assembly and installation of complicated and heavy mechanical items associated with the winder that is critical to the overall PHOX Project, culminating in the installation of the 80T assembly to extremely tight tolerances utilising our 400T heavy lift crawler crane.

Final handover to the customer is scheduled for early November 2025.