The accident comes after a tunnel collapsed at Freeport-McMoRan's giant Grasberg mine in Papua province on May 14, killing 28 workers undergoing safety training. The other 10 in the training session were rescued.
Herman Wahid died in hospital today, a day after a surge of wet ore material in an underground mine engulfed the truck he was operating.
The company said the accident was not related to the tunnel collapse, which occurred some two kilometres (1.2 miles) away, in one of the biggest mining accidents in the country's history.
Union officials said some of the company's more than 24,000 workers would not return to the site on safety concerns and until investigations were completed.
More From This Section
The first accident led to a two-week shutdown of operations at the mine, although Freeport said it had enough stocks to make its shipments.
Freeport resumed some activities on Tuesday as the Indonesian government and company conduct two separate probes into the tunnel collapse.