Fairview and Evander extension growth projects ensure sustainability for Pan African Resources
Extracting untapped gold reserves from orebodies that have been mined for decades takes ingenuity, and a focus on efficiencies. That is what Pan African Resources, one of South Africa’s low-cost gold producers, is applying to assets like Fairview and Evander.
Fairview, one of the mines that makes up the Barberton Mines complex, is around 130 years old. It was built in the days when miners followed the orebody as they found it. There is still a lot of gold left, but to extract it requires a “big picture” plan.
Intense drilling of the resource has helped Pan African to improve the predictability of its geological models and enabled it to plan for down-dip extensions to the orebody. It now has greater confidence in the grade control models which can be used to optimise mine design.
To date, a number of new mining platforms have been opened at the mine by Pan African, each with a life of about three years, which provides the flexibility to ensure a steady stream of material to the processing plant. As one platform is prepared for blasting, the others are in production. This was not possible previously with only one or two platforms available at any given time.
Striking gold with unmatched head rate
The focus is on the MRC and Rossiter orebodies. At MRC, a measured resource of 24 500 t at an average grade of 42.6 g/t has been delineated. With the orebody open at depth, the MRC is expected to have a 20-year life of mine. At Rossiter, drilling has intersected significant amounts of nugget-like free gold (which refers to almost pure gold, not bound up with other minerals). Grades range from 29 g/t over 2.9 metres to an eye-watering 165 g/t over 0.7 metres.
To put this into perspective, while there are still substantial South African gold reserves, the average grade enjoyed by the country’s gold mines is around 5 g/t. This is largely due to most mines exploiting Witwatersrand-type orebodies, which differ from the greenstone hosted mines around Barberton.
The increased flow of material from Fairview’s multiple mining platforms, in a mine that was not designed efficiently from the outset, necessitates new investment to alleviate bottlenecks of ore accumulating underground.
Designs for a new sub-vertical shaft at Fairview, which will help to bring down mining costs, are well advanced. This shaft will allow for production to grow by up to 10 000 oz./year by increasing hoisting capacity. There is also work in progress to develop and equip a decline shaft from level 42 to 64, which will decongest existing infrastructure and improve the production profile in the near term, as the shaft is being constructed.
Evander No. 8
Evander is a 66-year-old mine (sinking of the first shafts, Winkelhaak 1&3, began in 1956).
At Evander No. 8, work is under way on an extension to 24 Level to access the deeper 25 and 26 Levels. Construction of an extension from the No. 2 decline on 24 Level began in the first quarter of the 2022 financial year. The No. 2 decline was first built in the 1990s to extend the economic life of No. 8 shaft. The extension will provide access to the deeper levels of the orebody in the northwest, towards Rolspruit – a multi-million-ounce orebody situated at depth, which has not yet been mined as it would require sinking a brand-new shaft from surface to a depth of some 2,5 km – which would require significant capital and time.
Pan African intends to blast the development ends on 25 Level in the current financial year, and mine the first stope in the 2025 financial year. This work will extend Evander No. 8’s life for another 14 years. The plan is that, as mining at No. 8 shaft pillar tails off in around FY 2024, Evander 24 level will take over until FY 2026, and in turn will be replaced by Evander 25-26 level.
Peak funding for the 25 and 26 level extensions will be $52.1 million (ZAR 807 million), but using a gold price assumption of ZAR 882 060/kg, and at a recovered grade of 6.73 g/t, the estimated payback period from commencement of project development is five years.
This extension project will mine almost 600 000 oz. during its lifetime.
High-value, high-margin ounces
It is not often that a mining company can boast of finding another half to one million ounces with most of the infrastructure (including the processing facilities) capitalised and already in place – but Pan African has several projects which fit into this category.
This includes the Egoli project, for which a feasibility study has been completed. Egoli is being dewatered and will be developed and equipped for mining as the 25-26 Level mining commences, further adding life to the Evander complex. Egoli has a mineral resource of over half a million ounces and a life of mine of 9 years, with the potential to increase to 14 years when the available Inferred Resources are taken into account.
