Digital tools for tailings monitoring

Tailings ā€“ toxic waste products from mining ā€“ have long been a challenge for the mining industry. These hazardous materials are stored in dams, referred to as tailings storage facilitiesā€™ (TSFs), that measure tens of metres and, if destabilised, can cause loss of life/infrastructure and long-term pollution.

Exactly how to manage tailings materials is a question that is becoming increasingly pressing as traditional manual methods prove insufficient to keep up with demands. The World Bank estimates that for the global energy transition, three billion tonnes of minerals are needed by 2030 ā€“ with this figure only a fraction of the amount of waste materials that such efforts will generate.

Yet innovators and engineers are working to keep pace with the landscape, creating more sophisticated tools and software for miners to monitor and manage tailings facilities. Tools such as satellite sensing and machine learning (ML) are being increasingly deployed to enable in-depth, real-time monitoring. This allows miners to pursue rapid expansion without jeopardising safety standards.

The problem of tailings management

The World Mine Tailings Failures report estimates there are between 29,000 and 35,000 TSFs in the world. A quarter of these are abandoned or unmonitored.

The impact of damage to these structures, if left unchecked, has been evidenced time and again, with collapses seen at dams in Canada, Australia, South Africa and, most notably, at the Brumadinho dam in Brazil in 2019.

The Brumadinho disaster, where ten million cubic metres of waste burst out of the dam, killed at least 270 people, destroyed buildings and caused long-term environmental damage to the Paraopeba River, costing the mining company in question $7bn in damages.

While Brumadinho was not a unique event, it was a tragedy that served as a catalyst for regulatory change. It also renewed pressure on miners to update their systems.

One outcome was that the Church of England (which has a major stake in mining operations in Brazil) launched the Ethical Investors Group. This organisation requires mining companies to disclose the risk of tailings storage failures before receiving investment ā€“ putting pressure on miners to boost visibility of conditions across operations.

ā€œThis was amazing, because this kind of disclosure is typically very hard to get,ā€ says Maral Bayaraa, an Oxford University researcher investigating the use of satellite technology to create early warning systems for tailings dams.

Now, this kind of disclosure is crucial for mining companies seeking investment. An EY report found that of the environmental, social and governance factors facing the most scrutiny from investors in 2024, tailings and waste management is number two, with 55% of respondents identifying it as a concern.