Last week, the mining world took a significant step toward accountability when BHP and Vale reached a staggering 170 billion reais ($45 billion) compensation deal with Brazil over the catastrophic 2015 Mariana tailings dam collapse. This tragedy, which claimed 19 lives and devastated communities, was a wake-up call that echoed throughout the industry. The aftermath saw not just human suffering, but also environmental destruction—forests were submerged, and the Doce River became a toxic shadow of its former self. BHP’s chief, Mike Henry, aptly described the incident as a “terrible tragedy” that “should never have happened and must never be forgotten.”
Yet, if the Mariana disaster didn’t sufficiently raise alarms about the risks associated with tailings dams, the 2019 Brumadinho collapse, which killed 270 people, certainly did. These two disasters catalyzed a global conversation about the safety of tailings management, leading to the establishment of new standards aimed at preventing future catastrophes. But what do these standards really entail, and how will they ripple through the mining sector?
Tailings dams are a global issue, with thousands of them scattered across mining sites worldwide. They store the waste rock and leftover materials from ore processing, often containing hazardous substances like arsenic and mercury. A study published in Engineering Geology in 2022 highlighted a staggering 257 tailings dam failures since 1915, resulting in 2,650 fatalities and the release of 250 million cubic meters of contaminated waste. Alarmingly, nearly half of these failures have occurred since 2000. The mining industry has advanced technologically, allowing for the extraction of lower-grade ores, but tailings management practices have lagged behind, creating a ticking time bomb.
Climate change complicates this already precarious situation. Heavy rainfall, responsible for about 25% of global tailings dam failures, poses a growing risk as extreme weather events become more frequent. This reality necessitates urgent reform in how mining companies approach tailings management.
In response to these challenges, organizations like the International Council on Mining & Metals (ICMM) and the UN Environment Program have developed the Global Industry Standard on Tailings Management. This document asserts that the catastrophic consequences of tailings failures are simply unacceptable. Bruno Oberle, Chair of the Global Tailings Review, emphasized the need for a multi-disciplinary approach to effectively manage tailings facilities, urging all stakeholders to adopt the Standard and collaborate for improved safety.
However, not all tailings facilities are created equal. The use of upstream tailings dams, particularly in mountainous regions, has been a critical factor in both the Samarco and Brumadinho disasters. The construction method, which involves layering tailings behind an earth and rock wall, can create vulnerabilities. Research from ETH Zurich revealed that the Brumadinho collapse was driven by topographical “creep” under constant load, indicating that the disaster could have occurred without any external triggers like heavy rain.
In the aftermath, some countries have moved to ban upstream tailings dams altogether. While the new standards are a welcome development, they may also introduce new challenges. Building safer and more stable facilities could escalate costs, potentially impacting the viability of mining projects. Bruce Adkins, a partner at Johnson Winter Slattery, pointed out that the new standards might deter investment in regions with tricky mining topographies, as the past approaches are no longer deemed acceptable.
In a world increasingly reliant on critical minerals for decarbonization, the implications of these changes could be profound. However, there’s a silver lining—many in the industry recognize the necessity of adhering to the new standards, not just to avoid legal repercussions but also to protect their reputations. Adkins noted that the Standard is gaining traction as a global benchmark, influencing practices even outside the ICMM membership.
As the mining sector grapples with these evolving standards, the question remains: will companies rise to the occasion, or will the specter of past disasters haunt them as they navigate the complexities of modern mining? The stakes are high, and the world is watching.
