JOHANNESBURG (miningweekly.com) – The majority of diversified miner Exxaro’s operations were disrupted on Monday as mass strike action over the nonpayment of performance bonuses spread, a National Union of Mineworkers (NUM) branch secretary Mxolisi Hoboyi confirmed.

The strike action at the group’s Grootegeluk mine, in Limpopo, and the Mpumalanga-based Matla and Arnot coal mines continued on Monday, while workers at Exxaro’s Mpumalanga-based Leeuwpan and Inyanda coal mines joined the protest, he told Mining Weekly Online.

However, it was not immediately clear whether the JSE-listed group’s other coal operations, namely New Clydesdale and the North Block Complex operations, both also in Mpumalanga; and Tshikondeni, in Limpopo, were affected by strikes or if they would be soon.

Hoboyi was unable to expand on whether the remaining operations would join in the strike, as it was not an NUM-initiated strike; however, he noted that the workers were determined not to return to work until the bonuses had been paid.

Exxaro confirmed the strike action at the five operations and said it continued to work closely with State-owned power utility Eskom to ensure the availability of coal supply.

Hoboyi stated that, should the illegal strikes not be resolved by Tuesday, it was likely that South Africa’s power supply could be threatened as coal supply for the coal-fired power stations the mines were contracted to dried up.

The mines currently supplied coal to Eskom for the Matla and Arnot power stations, besides others.

Eskom last week warned of tight overall electricity supply as it struggled to meet demand – with a narrowing supply/demand margin – as repairs to Unit 1 of its Koeberg nuclear power plant, in the Western Cape, and the flood-damaged transmission line from Cahora Bassa, in Mozambique, continued.

Exxaro reported last week that contingency measures had been employed to maintain supply to the respective coal-fired Eskom power stations under contract.

By Friday, the Matla mine had 18 stock days of supply available, while the Matla power station had two stock days of supply on hand.

The Grootegeluk mining operations had a 14-day stock supply available on Friday for the Matimba power station, while the power station itself had 33 days of supply stockpiled.

The company noted, however, that Arnot held no risk to the supply of coal.