JSE-listed Harmony Gold has resumed shifts at its nine South African underground gold mines from Tuesday afternoon, after power utility Eskom had returned to lower stages of load-shedding.  

London-listed Petra Diamonds also resumed its South African mining operations on Tuesday, albeit at a 20% load curtailment.

The power utility on Monday implemented Stage 6 load-shedding for the first time, after some of its power stations in Mpumalanga were affected by flooding, exacerbating the already constrained power supply situation.

As a result, Harmony, Petra and JSE-listed Sibanye-Stillwater cancelled some shifts at its South African mines.

The utility later scaled back to Stage 4 and then Stage 2 load-shedding and, on Tuesday, said it was likely to implement load-shedding throughout the remainder of this week.

Eskom requested that power only be used for maintenance of essential services during Stage 6 loadshedding.  

Petra noted that it was used to managing its operations optimally to maintain production levels as much as possible throughout load-shedding requests.

Such measures included bringing forward essential maintenance work and restricting load curtailment to processing plants, where possible, given that the company’s operations have excess processing capacity, allowing for additional throughput when full power is restored.

However, Petra pointed out that the impact of the current load curtailment would depend on the duration and level of severity of the power restrictions going forward.

Sibanye-Stillwater confirmed to Mining Weekly Online that it had to cancel three shifts following the Stage 6 announcement.

The miner implements load curtailments of 10% during Stage 1 and Stage 2 load-shedding, but typically has to stop milling and concentrator operations from Stage 4.

Meanwhile, JSE-listed Merafe Resources said that the lower Stage 4 load-shedding, coupled with the challenging economic environment, was enough to negatively impact on the future viability of some of its operations and the wider ferroalloys sector in South Africa.

The company continued to engage with all stakeholders to determine what measures could be implemented to help alleviate the significant external pressures facing the industry.