Opponents of a big mining project in the Dominican Republic asked a judge Tuesday to halt the Canadian company's operation until it addresses their concerns over the environmental impact.

A consortium involving Barrick Gold and Goldcorp is making a US$3-billion investment to reopen the Pueblo Viejo mine and plans to begin extracting gold, silver and other minerals late next year.

The judge at the hearing in the capital of Santo Domingo ordered a 20-day period for each side to respond to the opposing arguments before she issues a decision.

Environmentalists claim the company is relying on a permit granted in 2001 when the scope of the project was much smaller.

"We want Barrick's operations stopped until they complete impact studies and they have a new licence," said Alexander Mundaray, a plaintiff in the lawsuit and among environmentalists who have led demonstrations against the project.

A Barrick spokesman, Jorge Esteva, said he could not discuss the company's documentation because of pending legal proceedings but added that "our operations are always conducted within the framework of the law".

The Caribbean nation's environmental ministry presented documents at the hearing to demonstrate that the project already has been approved.

The mine previously operated from 1975 to 1999.

- AP