Name of the Project
Carrapateena block cave expansion.

Location
The project is located in South Australia’s highly prospective Gawler Craton.

Project Owner/s
OZ Minerals.

Project Description
The Carrapateena project, currently in construction, will mine an 84-million-tonne inventory using the sublevel caving method.

First sublevel cave production is scheduled for the fourth quarter of 2019, followed by ramp up over an 18-month period to produce 4.25-million tonnes a year.

The sublevel cave will produce an average of 65 000 t/y of copper and 67 000 oz/y of gold over a 20-year mine life.

A scoping study on the Carrapteena block cave expansion has determined that replacing the lower half of the sublevel cave with a block cave and expanding the throughput rate from 4.25-million tonnes a year to between 10-million and 12-million tonnes a year from 2026 can create significantly more value than the sublevel cave alone. The block cave would be supported by expanded surface infrastructure.

Two options have been identified for increasing the current sublevel cave processing plant capacity to either a new parallel processing plant or upgrading the current sublevel cave processing plant.

Within the plant upgrade option, there are two suboptions – a parallel milling circuit or a tertiary crushing circuit.

The study has recommended the plant upgrade route with a tertiary crushing circuit as the most likely path for increasing processing plant capacity; however, both primary options can feasibly meet the requirements of the scoping study.

A block cave expansion of the lower portion of the current Carrapateena sublevel cave has the potential to increase average life-of-mine copper production from 65 000 t/y to between 105 000 t/y and 125 000 t/y from 2026.

The project will unlock possible future value accretive options for the Carrapateena life of province plan.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
Not stated.

Capital Expenditure
Preproduction capital is estimated at between $1-billion to $1.3-billion, in addition to the A$916-million cost of the current Carrapateena development.

Planned Start/End Date
Not stated.

Latest Developments
OZ Minerals produced the first saleable copper/gold concentrate into the prefilter press feed tank at its Carrapateena project in December 2019.

The concentrate production milestone was met within the fourth-quarter schedule mapped out at the project’s approval in 2017.

The miner has reported that more than 280 000 t of development ore has been stockpiled on the surface, as the mine now enters a faster ramp-up towards full throughput rates by the end of 2020, dependent on the cave performing as expected.

OZ has already started a block cave expansion scoping study, to consider increasing the life and production capacity of Carrapateena from 2025.

Key Contracts and Suppliers
None stated.

On Budget and on Time?
Too early to state.

Contact Details for Project Information
OZ Minerals, tel +61 8 8229 6600 or email info@ozminerals.com.