Name and Location
Ivanplats Platreef project – platinum group metals (PGMs), nickel, copper and gold mine, Limpopo, South Africa.

Client
Ivanhoe Mines owns 64% of the Platreef project through its subsidiary Ivanplats and manages all project development work. The South African beneficiaries of the approved broad-based black economic-empowerment (BBBEE) structure have a 26% stake in the project, and the remaining 10% is owned by a Japanese consortium of ITOCHU Corporation; Japan Oil, Gas & Metals National Corporation; ITC Platinum Development, an ITOCHU affiliate; and JGC.

Ivanplats is the top-ranked platinum-sector mining company in terms of compliance with South Africa’s black economic-empowerment laws. The company achieved Level 3 status on the BBBEE scorecard in 2015 and 2016.

The communities around the Platreef project are widely consulted, with about 150 000 members becoming equity shareholders and an estimated 74% of employees and contractors coming from surrounding communities.

Project Description
The Platreef project is a Tier 1 discovery, which contains the underground Flatreef deposit of PGMs, copper, nickel and gold, located on the northern limb of South Africa’s Bushveld Igneous Complex – the world’s premier platinum-producing region. Ivanplats has declared an initial probable mineral reserve of 15.51-million ounces of platinum, palladium, rhodium and gold (3PE+Au). The mineral reserve is expected to support a 31-year mine life at steady-state production of four-million tonnes a year.

An independent preliminary economic assessment (PEA), which was completed in March 2014, proposed a three-phased approach to Platreef’s long-term development. The Platreef prefeasibility study (PFS), which was completed in January 2015, validated the results of Phase 1 of the independent PEA.

Key features of Phase 1 include:
• the development of a large, mechanised underground mine, with an initial four-million-tonne-a-year concentrator and associated infrastructure; and
• a planned, initial average yearly production rate of 433 000 oz of 3PE+Au, and 19-million pounds of nickel and 12-million pounds of copper a year.

Among the current and future northern limb producers, Platreef will rank near the bottom of the operating cash-cost curve, at an estimated $322/oz of 3PE+Au, net of by-products credits.

Phase 2 involves an expansion of the mine to double production to eight-million tonnes a year.

The third phase involves a further expansion of the mine to a steady state of 12-million tonnes a year, placing it among the largest PGMs mines in the world.

Mining zones in the current Platreef mine plan occur at depths ranging from about 700 m to 1 200 m below surface.

Access to the mine will be through two vertical shafts. Shaft 1 is currently under development and will be used for initial access, early underground development and ventilation. The shaft will have an internal diameter of 7.25 m and is projected to reach a total depth of 975 m in 2018. Additional dedicated ventilation shafts will be provided to support mine development. Shaft 2 will comprise the main personnel, materials and ore-handling system.

Highly productive, mechanised methods will be used for mining, including long-hole stoping and drift-and-fill mining. The ore will be hauled from the mechanised stopes to the bottom of Shaft 2, where it will be crushed and then hoisted to the surface. Shaft 2 will have a finished internal diameter of 10 m and will be equipped to hoist up to six-million tonnes a year.

Net Present Value/Internal Rate of Return
Phase 1 has an after-tax net present value of $972-million, at an 8% discount rate, and an after-tax internal rate of return of 13%.

Value
The estimated preproduction capital requirement for Phase 1 is about $1.2-billion, including $114-million in contingencies.

Duration
According to the latest PEA released, Phase 1 is expected to be completed by 2019.

Phase 2 is expected to be completed by 2024 and Phase 3 by 2028.

Latest Developments
The changeover from presinking activities to the main sinking activities at Shaft 1 of the Platreef project is expected to be completed by April, allowing for the start of main sinking.

Presinking of the shaft has been completed to 54 m below surface. Initial shaft-sinking activities – drilling, blasting and mucking – started on October 26, 2015, following the successful construction of the shaft collar and ventilation plenum.

Shaft 1 will be used for initial access to the orebody and early underground development.

The Platreef project is owned by Ivanplats – which is 64%-owned by Ivanhoe Mines – and hosts an underground deposit of thick PGM, nickel, copper and gold mineralisation in the northern limb of the Bushveld Igneous Complex, about 280 km north-east of Johannesburg and 8 km from Mokopane, in Limpopo.

The main access to the orebody and ventilation system is expected to comprise four vertical shafts.

During the main sinking of Platreef’s Shaft 1 shaft sinking contractor Aveng Mining expects to sink at a daily average rate of about 2.5 m. Aveng is also responsible for the excavation of the boxcut access for the shaft collar and vent plenum. The fabrication of the temporary sinking headframe and centre tower was completed during the third quarter of 2015 and delivered to site.

Shaft 1 is expected to reach the Flatreef deposit at a depth of 777 m below surface by late 2017 and reach its total depth of 975 m in 2018.

The Flatreef mineral resource, with a strike length of 6.5 km, lies predominantly within a flat to gently dipping portion of the Platreef mineralised belt at relatively shallow depths of about 700 m to 1 100 m below the surface.

Ivanhoe has noted that work has been completed on the internal electricity substation, which has a capacity of five-million volt-ampere. Construction is under way on the power transmission lines from State-owned power utility Eskom, which will supply the electricity for the sinking of Shaft 1. Back-up generators have been installed to ensure continuous sinking operations, even if the power supply from Eskom is interrupted.

“Other on-site work includes the construction of the primary terraces for Shaft 1, stormwater drains and ponds, workshops and stores. A total of 511, or 74%, of the 693 permanent and contract workers presently employed by Ivanplats are from the local area,” says the company.

Meanwhile, the headgear design for the six-million-tonne-a-year permanent hoisting facility for Platreef’s Shaft 2 has been completed by mining services company Murray & Roberts Cementation.

Ivanhoe expects to start Shaft 2 early works in 2017, including civil work for the boxcut and hitch foundation. Designs for the boxcut have been completed and the contract for the early engineering works for the winding equipment has been awarded to South Africa-based global engineering company FLSmidth.

Shaft 2 will host the main personnel transport cage, materials and ore-handling systems, while shafts 1, 3 and 4 will be used for ventilation to the underground workings.

“Mining will be performed using highly productive, mechanised methods, including long-hole stoping, drift-and-bench and drift-and-fill mining methods. The mined-out areas within the orebody will be backfilled with a paste mixture that uses tailings from the process plant and cement. The ore will be hauled from the stopes to a series of ore passes that connect to a main haulage level, which will be connected to Shaft 2, where it will be hoisted to the surface for further processing,” outlines Ivanhoe.

Since 2007, Ivanhoe has focused its exploration activities on defining and advancing the down-dip extension of its original Platreef discovery, now known as the Flatreef deposit, which the company says is potentially amenable to highly mechanised underground mining methods. The Flatreef area lies entirely on the Turfspruit and Macalacaskop properties.

Key Contracts and Suppliers
DRA Projects (PFS, feasibility study, mining, concentrator and infrastructure); OreWin (National Instrument 43-101 technical report); Aveng Mining (Shaft 1 sinking contractor); Murray & Roberts Cementation (design and engineering for shaft infrastructure); Stantec Consulting (mine planning); Golder Associates (water studies, backfill and tailings); Digby Wells Environmental (social and environmental); SRK (geotechnical) and Mintek (metallurgical testwork).

On Budget and on Time?
Phase 1 is under development, during which an operating platform will be established to support the start of production, which is expected by 2019.

Contact Details for Project Information
Ivanplats VP and executive head: capital projects Gerick Mouton, tel +27 11 088 4300 or email gerickm@ivanplats.com.
DRA Projects, tel +27 11 202 8600 or email info@DRAglobal.com.
OreWin, tel +61 8 8210 5600 or email orewin@orewin.com.
Aveng Mining, tel +27 10 207 7000, fax +27 10 207 7202 or email info@avengmining.com.
Murray & Roberts Cementation, tel +27 11 201 5000 or email info.cementation@murrob.com.