Name of the Project
Platreef palladium/platinum/rhodium/nickel/copper/gold project.

Location
Northern limb of South Africa's Bushveld Igneous Complex, in Limpopo.

Project Owner/s
Ivanhoe Mines indirectly owns 64% of the Platreef project through its subsidiary, Ivanplats, and is directing all mine development work.

The South African beneficiaries of the approved broad-based, black economic-empowerment structure have a 26% stake in the Platreef project. The remaining 10% is owned by a Japanese consortium comprising Itochu Corporation; Japan Oil, Gas and Metals National Corporation; Itochu affiliate ITC Platinum Development; and Japan Gas Corporation.

Project Description
Ivanhoe Mines has reported outstanding positive findings of an independent Platreef integrated development plan 2020 (Platreef IDP20) for the tier-one project. The project has total probable reserves estimated at 124.7-million tonnes as at November 30, 2020, for seven-million ounces of platinum, eight-million ounces of palladium, 1.2-million ounces of gold, 500 000 oz of rhodium, 457-million pounds of copper and 932-million pounds of nickel.

The Platreef IDP2020 encompasses two devel­opment scenarios. 

The Platreef 2020 feasibility study – an update of the 2017 feasibility study –  evaluates the development of a 4.4-million-tonne-a-year under­ground mine, with two concentrators built in modules of 2.2-million tonnes a year. This updates the 2017 feasibility study by taking into account the development achieved since then, as well as updated costs, metal prices and foreign exchange assumptions, in addition to increased throughput from four-million tonnes a year to 4.4-million tonnes a year to use the full processing capacity of the two concentrators.

The feasibility study has an average production of 508 000 oz/y of platinum, palladium, rhodium and gold, plus 22-million pounds of nickel and 13-million pounds of copper.

The alternative Platreef 2020 preliminary eco­nomic assessment (PEA), or phased development plan, evaluates the phased development of an initial 700 000 t/y underground mine using the existing Shaft 1 and a new 770 000 t/y concentrator, targeting high-grade mining areas with significantly lower capital costs.

After first production is achieved, Shaft 2 sinking will start to coincide with the construction of two additional 2.2-million-tonne-a-year concentrator modules and the ramp-up of the initial concentrator to its full capacity of 770 000 t/y, increasing steady production to 5.2-million tonnes a year.

Shaft 2 development may be brought forward to accelerate this expansion.

The PEA envisages Phase 1 during years 1 to 6 at an average production 109 000 oz/y of plat­inum, palladium, rhodium and gold (3 PGE + Au), plus five-million pounds of nickel and three-million pounds of copper.

Average production for Phase 2 – years 7 to 30 – is 613 000 oz/y of 3 PGE + Au, plus 27-million pounds of nickel and 16-million pounds of copper.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
The feasibility study yields an after-tax net present value (NPV), at an 8% discount rate, of $1.85-billion and an internal rate of return (IRR) of 19.8% at a long-term consensus metal price, with a payback of 4.4 years. At spot metal prices, the feasibility study estimates an after-tax NPV, at an 8% discount rate, of $3.74-billion and IRR of 28.4%, with a payback of 3.2 years.

The PEA yields an after-tax NPV, at an 8% discount rate, of $1.61-billion and IRR of 20% at long-term consensus metal prices, and an after-tax NPV, at an 8% discount rate, of $3.3-billion and IRR of 29.1% at spot metal prices. Payback at long-term consensus metal prices is estimated at 8.4 years and at spot metals prices at 7.3 years.

Capital Expenditure
The Platreef 2020 feasibility study estimates initial capital costs for the project at $1.4-billion.

The PEA estimates an initial capital cost of $390-million. Expansion capital is estimated at $1.27-billion.

Planned Start/End Date
The Platreef IDP20 envisages Shaft 2 equipped for hoisting in 2025, allowing for first concentrate production in the latter half of the year.

The PEA envisages first concentrate production for this option in 2024, with the sinking of Shaft 2 restarting in 2025 to coincide with the con­struction of two 2.2-million-tonne-a-year concentrators to be completed by 2029 and 2030.

Latest Developments
Platreef's updated feasibility study for the phased development plan is progressing well towards completion in early 2022.

All design and engineering work has been completed, with the cost estimates well advanced.

The Shaft 1 changeover is progressing well in preparation for permanent rock hoisting in early 2022.

The construction of the 996-m-level station at the bottom of Shaft 1 was completed in July 2020.

Shaft 1 will initially be used to access the orebody and is about 350 m away from a high-grade area of Flatreef that is planned for bulk, mechanised mining. The three development stations that will provide initial, underground access to the high-grade orebody have also been completed on the 750 m, 850 m and 950 m levels.

Construction of the auxiliary winder foundations has been completed, and the auxiliary winder installed and commissioned.

The changeover construction at Shaft 1 is progressing to plan and is on schedule for the start of rock hoisting in early 2022. All equipment for the shaft changeover has been procured and is on site. The changeover work within the shaft is being done by Platreef’s experienced owners’ team.

The winder that was used to successfully sink Shaft 1 has been converted to function as the main equipping conveyance during the shaft changeover, and will serve as the permanent rock, personnel and material winder following the shaft-equipping phase. The shaft will be equipped with two 12.5 t skips, with a hoisting capacity of 825 000 t/y, and an interchangeable personnel and materials conveyance to accommodate the movement of personnel and materials during the initial phase of mining.

Rope guides will be used for the main rock, personnel and materials conveyances, while steel sets and guides will be used for the auxiliary winder conveyance. The stage and winder ropes used during the sinking phase have been removed, and the new equipping stage, permanent guide-ropes and permanent hoisting ropes have been installed.

The auxiliary winder has been installed and commissioned to assist during the shaft and station equipping phase, and to function as a personnel winder during the main rock-hoisting cycle. Shaft equipping is progressing well, with the permanent service pipes, guides, electrical cables and other control cables successfully installed down to the 950 m level. 

Newly designed rock chutes will connect the conveyors feeding the concentrator plant and waste-rock area; from there the waste rock will be crushed and used as cemented backfill underground, as well as for protection berms to contain stormwater and reduce noise emissions.

Shaft equipping started in May 2021 and remains on track to be completed in early 2022.

Following the completion of the changeover work in the shaft, underground stations and establishment of the ore and waste passes, lateral underground mine development will start towards high-grade ore zones.

The waste conveyor, which will be fed from Shaft 1, is progressing to plan, with all mechanical and electrical orders well advanced. Delivery of the radial stacker is planned for February 2022 and the complete waste conveyor load-out system is expected to be fully operational by early 2022.

Ivanplats has placed an initial order with Epiroc of Stockholm, Sweden, for its primary mining fleet consisting of emissions-free, battery electric jumbo face drill rigs and load-haul-dump vehicles, due for delivery in early 2022.

The Shaft 2 headframe construction, from the hitch to the collar level, is progressing well, with the third and fourth headgear lifts well advanced. Ten civil lifts are to be constructed, including a ventilation plenum and personnel access tunnel, with targeted completion in May 2022.

Key Contracts, Suppliers and Consultants
OreWin (Platreef IDP20); Epiroc (emissions-free, battery electric drill rigs and underground loaders).

Contact Details for Project Information
Ivanhoe Mines, tel +27 11 088 4300 or email info@ivanhoemines.com.