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SANTIAGO, Sept 5 (Reuters) - Striking workers at Codelco's small Salvador copper deposit in Chile have blocked access to the mine and are affecting production, the company and union said on Monday.
The union last week said it would go on strike this week after failing to reach agreement in contract talks.
Codelco told Reuters that protests began on Sunday night and that currently "the mine has been occupied and operations are paralyzed."
In a statement on Monday, the state-run copper producer said that its final contract offer had been approved by the union covering Salvador's concentrator workers, but rejected by the refinery and smelting union. That had triggered a legal strike, which had prevented those not on strike from doing their job.
"It is not yet possible to quantify the effects of this strike in production terms, as that depends on the extent of the stoppage," the company said.
Employees who are not part of the protest were unable to get to work, union spokesman Waldo Gomez told Reuters.
"As we have cut off the access to work, they can't go up ... The only tasks being are done are those in the very basic operative line, but it's not producing at 100 percent," he said.
Salvador produced 49,000 tonnes of copper in 2015. It is one of world no.1 copper exporter Codelco's smallest and highest cost mines, and the company is battling to keep a lid on costs to ensure production is viable at a time when copper prices are low.
Last year Salvador was hit by an around three-week strike by a different group of contract workers. (Reporting by Fabian Cambero, Writing by Rosalba O'Brien, Editing by Franklin Paul and James Dalgleish)