A mine worker at the Grasberg mine in Indonesia's remote province of Papua says some workers are back on the job after the mine began operating on Monday.
Darmawan Puteranto says the workers union he belongs to is still holding meetings to discuss workers' conditions.
Freeport, the owners of the world's biggest copper and gold mine, announced they would recommence operations this week after the government gave the green light.
The government has not released its report into the disaster that claimed 28 lives in May when the roof of an underground training facility collapsed.
It has also not given permission for restarting operations in the underground facility yet.
The President Director of Freeport Indonesia Rozik Soetjipto told the Jakarta Globe that output from the open-pit mine may reach normal levels in three to four days.
Last week a riot at the mine facility destroyed vehicles and other property.
An independence activist says it was prompted by locals who were starving from not having any work.