Chile state-owned copper producer Codelco has submitted a modified proposal for its $6.8bn Andina 244 project, after locals opposed it fearing impact on glaciers and water resources in the region.
The company has agreed to recycle 65% of the water used at the mine and improve the quality of water in the Blanco river by building two new water treatment plants.
Codelco acting projects head Gerhard von Borries was quoted by Reuters as saying: "Two out of every three litres of water that the Andina expansion needs will come from recycled water, making the project very efficient in terms of water resources.
"We've changed the layout of the open-pit mine, which allows us to reduce the number of rock glaciers that will partially be affected."
The company has added these modifications to its original environmental impact study and submitted the application to Chilean environmental authorities.
Codelco expects the mine to boost production as it faces drop in output from older mines. The company aims to produce 600,000t of copper a year with the expansion of the mine.
The project had previously received over 2,000 complaints from local residents, NGOs and legislators, on its potential impact on the regions' glaciers and water supplies.
Codelco corporate affairs and sustainability vice-president Rene Aguilar said: "We've worked for over a year to consider each of the comments we received, holding dozens of meetings, workshops, listening to the community, authorities and experts.
"Today we have a better project, with more information and new measures that address the main concerns and that reduce the project's impact on its surroundings."