A diamond mine in the rough

Monday, February 16, 2015

Diavik Diamond Mine at Lac de Gras, Northwest Territories, CanadaAcid mine drainage is one of the mining industry’s top environmental liabilities. It’s estimated mining operations in Canada alone spend $100 million annually to treat mine waste discharge, with clean up costs of existing acid mine drainage pollution potentially totaling between $2 and $5 billion.

Researchers at the University of Waterloo's Faculty of Science, along with colleagues from the Universities of Alberta and British Columbia, and Carleton University have collaborated with Diavik Diamond Mines to develop a sustainable method of mitigating acid mine drainage.

Their ten-year collaboration was recognized with an NSERC Synergy Innovation Award, announced this week.

Professor David Blowes

Canada strives to be one of the leaders in environmentally sustainable mining,” says Canada Research Chair David Blowes, Principal Investigator and Professor of Earth and Environmental Sciences. “Integrative research projects of this kind are key to the development of appropriate management strategies for mine waste.”

Acid mine drainage is produced when the sulphide minerals in exposed waste rock from mining activities react with air and water to produce acidic runoff which has the potential to destroy nearby water resources and aquatic ecosystems and mobilize heavy metals such as copper, lead and zinc. According to the federal government, Canada produces more than a million tons of waste rock per day.

The Diavik mine, a source of top-quality, gem-grade diamonds, is located on an island in a pristine lake in Canada’s Northwest Territories.

The researchers monitored three test waste piles for signs of chemical and biological activity using the latest analytical techniques. The research team also adapted a reactive transport model to the site to understand the dynamics of the system and test for potential scenarios, including the effects of climate change.

The comprehensive field study demonstrated it’s feasible to isolate the mine’s acid generating waste rock in a frozen state beneath an insulating soil cover. Maintaining frozen conditions is sustainable because of the mine’s extreme northern location within a continuous permafrost zone.

The team’s research approach is now working its way around the globe, helping mining companies worldwide design more cost-effective mitigation strategies that better protect the environment.

Blowes and his team plan to incorporate the Diavik Diamond site into the TERRE-CREATE program, another NSERC funded program designed to train the next generation of sustainable mining professionals.

This is Blowes’ second Synergy award. His first won the award with Earth and Environmental Science professors Emil Frind and Carol Ptacek back in 1999 for their partnership with the Ontario-based natural resources company Falconbridge Ltd.