Deep-level investment

Gold major Harmony’s strategy is to direct major capital towards its highgrade underground mines and high-margin surface source operations to improve profitability.

The decision to extend Mponeng, already the world’s deepest mine, to over 4 km is an example of its commitment to South African gold mining as it creates long-term value for all stakeholders.

“Harmony will continue investing development capital into other operations to ensure flexibility and optimal cash flow generation over the life of its other mines,” says Harmony Group CEO Peter Steenkamp.

He adds that Harmony operates various deep-level mines that stretch below 2 000 m underground, which rely heavily on labour.

Steenkamp explains that people are Harmony’s most important asset, and therefore, the company is investing significant resources to transform its safety culture, while also ensuring a safe working environment at all times.

One of Harmony’s core initiatives is its S300 initiative, which aims to get Harmony blasting crews to achieve an average of 300 m2 per month, safely. This safety and productivity initiative factors in many strategies including Harmony’s Thibakotsi humanistic culture transformation initiative.

“Thibakotsi means ‘prevent harm’ in Sesotho and is transforming the hearts and minds of our employees, ensuring a positive safety culture throughout Harmony,” Steenkamp highlights.

Further initiatives include panel pairing, face time optimisation, personless boxholes, drilling technology improvements, and improved logistics and gold plant recoveries.

Sustainably Embedded

“Sustainability has always been embedded in our operating model. We have a risk-based approach to decision-making and all environmental, social and governance (ESG) aspects are factored into our operations across the globe,” he states.

Additionally, as the South African economy continues to face various challenges, Steenkamp points out that it is critical Harmony works proactively to maintain stability and strong relations with all stakeholders.

Steenkamp explains that community relations are vital in maintaining Harmony’s social licence to operate, and, in this regard, the company’s approach to working with communities ensures it remains the partner of choice.

“Environmental pressure is also increasing, and we must find new ways to recycle water and waste material,” he says, adding that Harmony has invested in two water companies: the Margaret Water Company in the Vaal River region, and Covalent Water Company in the West Wits region.

In addition, Harmony is a significant producer of gold from the retreatment of old tailings dams.

“This has ensured we are part of the circular economy and can create long-term value through the hydro mining of old tailings storage facilities across South Africa.”

Face to Face

Many of Harmony’s existing mines are mature and the distance from the shaft infrastructure to the mining face is getting ever further as it continues to extend the life of its existing mines.

Consequently, the company has to look at optimising face time to ensure safe mining practices, and that it can obtain the necessary volumes to keep its mining operations commercially viable.

In addition, there is always the risk of seismicity in deep level mines, meaning that mining techniques must evolve and adapt as the mine progresses deeper.

“A deep mine is not necessarily a more dangerous mine, but it does require a good understanding of the geology and geotechnical stresses to ensure we mine safely,” stresses Steenkamp.

In this regard, he explains that Harmony’s rock engineers continue to work closely with tertiary education institution University of Pretoria to continuously improve its understanding of seismicity.

Some other key factors that need to be considered include Harmony’s access to capital and skills.

Deep-level Considerations

Steenkamp says one of significant factors involved with deep-level mining is the requirement for vast refrigeration and ventilation.

Historically, South African mines had access to abundant and cheap coal-fired power through State-owned power utility Eskom; however, the power environment is changing, and miners face new challenges such as decarbonisation targets and pressure, and significantly higher energy costs and variable supply thereof.

“As we mine deeper, virgin rock temperatures increase, and keeping the mines cool becomes more costly and challenging,” he says. For this reason, Harmony has actively engaged in rolling out a comprehensive renewable energy programme.

Phase 1 of the Harmony Gold Welkom solar photovoltaic (PV) park, in the Free State, which was commissioned in August 2023 through a power purchase agreement, already provides 30 MW of renewable solar PV power for the miner.

“We will be starting with Phase 2 in due course, which will add another 167 MW of renewable solar generation capacity by financial close of 2026.”