The manager of the Rovic diamond mine near Dealesville in the Free State, where 20 people died in November 1996 after a mudslide, on Wednesday pleaded guilty in the Virginia Regional Court to charges of manslaughter, Beeld reported on Thursday.
Judgement against Pieter Smith, 56, will be given by magistrate Johan Bosch on Friday.
Smith acknowledged that negligence contributed to the disaster and that he had been negligent by not properly investigating a sagging in the floor of the mine.
Business manager of the mine and managing company Merorex, Jomo King, in a plea explanation also pleaded guilty to the charges on behalf of the company. Judgment against him will also be given on Friday.
Fourth accused, Kobus Olivier, who was mine supervisor at the time of the disaster, indicated that he would plead not guilty to the charges.
His trial was postponed to January 31 next year.
Twenty people died, two were injured and the lives of 54 others were endangered when underground workers were buried under thousands of tons of mud.
The inquest that followed found that there been enough evidence of hidden danger at the mine. - Sapa