SANTIAGO, Feb 3 (Reuters) - Chile's Escondida, the world's biggest copper mine, said it had begun a voluntary redundancy program for its workforce as part of an ongoing plan to improve productivity and cut costs.
Escondida, controlled by global miner BHP Billiton , said in a statement late Monday that the "extraordinary program" would include redundancy payments as well as education and health bonuses.
It did not say what percentage of workers it was expecting to lay off.
The mine's union, Sindicato No. 1, said it thought the provisions in the plan were "insufficient" and expressed concern about what actions the company would take if not enough workers take up the offer.
Escondida, in Chile's Atacama Desert, produced 1.19 million tonnes of copper in 2013 and employed around 4,300 staff. BHP has a 57.5 percent stake and Rio Tinto owns 30 percent. (Reporting by Rosalba O'Brien; Editing by Peter Galloway)