Mining firms BHP Billiton and Rio Tinto are moving ahead on a planned $3.43-billion water-supply project for the Escondida copper mine in Chile's high desert. The upgrade will include the largest seawater reverse-osmosis desalination plant in the Americas, says Black & Veatch, which announced on Oct. 29 its selection as engineer-of-record for the facility and related marine works. The plant is set to produce about 220,000 cu meters of water a day.

The two mining firms are the majority owners of Escondida, the world's largest copper mine, located 3,100 m above sea level. Its water-supply project, to be commissioned in 2017, also includes two pipelines, four high-pressure pump stations, a reservoir and power infrastructure.

Water will be supplied to the mine via a 180-kilometer pipeline from Anto-fagasta. Peter Beaven, president of BHP's copper business, said the project will "secure a reliable water supply and minimize our reliance on the region's aquifers." A new, 152,000-ton-per-day copper concentrator also is being completed at Escondida. Bechtel, which has worked at the mine in the past, is program manager for the current expansion, according to a company spokesman.

In late summer, South Korea's Doosan Heavy Industries & Construction said it won the contract to build the facility over competitors, including France's Degremont, Spanish firms Acciona and Valorza Agua, and Israel's IDE Technologies. Doosan says this is its first desalination project outside the Middle East.

The next-largest seawater desal plant in the Americas is the 189,250-cu-m/day facility being built in Carlsbad, Calif. In October, IDE announced that its 624,000-cu-m/day plant near Tel Aviv is operational. The plant is the first large-scale facility to use an advanced technology that includes 16-in. membranes in a vertical arrangement, the company said. An International Desalination Association spokeswoman says the Shoaiba 3 plant in Saudi Arabia produces 880,000 cu m/day and that China is planning a facility that could be as large as 1 million cu m/day.