SAN JUAN, Puerto Rico (AP) — Production will start in August at the huge Pueblo Viejo gold mine in the Dominican Republic, the CEO of the world's largest gold company said Thursday.

Barrick Gold Corp. CEO Jamie Sokalsky told analysts and investors on a conference call that Pueblo Viejo is "essentially complete" after an investment of about $3.8 billion. He said that the mine is expected to produce up to 125,000 ounces of gold this year and to reach full production in 2013.

Pueblo Viejo, a joint venture of Toronto-based Barrick and Goldcorp Inc. of Vancouver, is expected to be among the world's most productive gold mines.

The project, the largest private investment ever in the Dominican Republic, is operating at the site of a former state-owned mine that caused extensive environmental damage.

Also on Thursday, Sokalsy said the company's plans to open the world's highest-altitude gold mine straddling the Chile-Argentina border are off-track, facing delays and cost-hikes.

Sokalsky said the planned Pascua-Lama project will cost up to 60 percent more than previously estimated, raising the cost of the mine to as much as $8 billion. He said the project has become more complicated, and that he's trying to get the mine "back on track" so that the first gold can be produced in mid-2014.

Argentina's Supreme Court this month overruled Barrick's injunctions against enforcement of a law meant to protect the country's remaining glaciers. Barrick denies it, but environmentalists say the planned mine would violate the law.