PERTH (miningweekly.com) – Mining majors BHP Billiton and Rio Tinto will jointly invest $3-billion into a new 2 500 l/s seawater desalination facility for the Escondida copper mine, in Chile.

The Rio board has approved a $1.03-billion budget for its 30% interest in the project, while BHP will provide the remaining $1.97-billion.

The miners said on Friday that the desalination project would provide a sustainable supply of water for the organic growth project at the copper concentrator, which was approved in 2012, while limiting the project’s reliance on the region’s aquifers.

Construction of the new plant will start this month and will include the development of two pipelines, four high-pressure pump stations, a reservoir at the mine site and high-voltage infrastructure to support the system.

The new facility will be commissioned in 2017.

“Securing a sustainable water supply in the Atacama Desert is a major priority for all Chilean copper producers, so the approval of the Escondida water supply project is a significant milestone for our business,” BHP’s copper president Peter Beaven said on Friday.

“The new desalination facility will reduce our reliance on the region’s aquifers, which will help us to meet our environmental commitments and enable us to achieve our long-term business strategy.”

The desalination plant forms part of the organic growth project 1 (OGP1), which is aimed at replacing the Los Colorados concentrator with a new 152 000 t/d plant, and allowing access to higher-grade ore located underneath the existing facilities.

Construction of OGP1 started in February last year and commissioning is expected in the first half of 2015, increasing production to 1.3-million tonnes a year. The project will cost $3.8-billion and create up to 7 000 jobs during the construction phase.

The Escondida project is 57.5% held by BHP and 30% by Rio, while a 10% interest is held by the Jeco Corporation and the remaining 2.5% by Jeco 2.