According to a report made Tuesday, Toronto-based Hudbay Minerals is looking to sell a portion of its ownership in the Rosemont Mine.

The proposed open pit copper mine in the Santa Rita Mountains southeast of Tucson would be the third largest copper mine in the United States.

Toronto-based majority owner Hudbay Minerals says it is selling a 30 percent stake in the project.

Bloomberg analysts following the process say the size of the sale is expected to attract new funding. Current investors say the mine has been mismanaged and suffered production delays and losses.

The mine was fully permitted in March to begin construction. Local tribes and environmentalists say the operation will destroy sacred lands, pollute the water supply and hurt wildlife habitat.

Hudbay acquired the Rosemont project in 2014. The mine will account for about 10 percent of the country’s total copper production.