25 January 2019 had seemed like a normal enough day for the iron mine workers in Brumadinho, in Brazil’s Minas Gerais province. Many were taking their lunch break when, at 12:28 surveillance cameras showed the almost 90 metre high earthen dam instantaneously pulverised. In just a few seconds 12 million cubic metres of water and waste from mineral processing submerged everything within seven kilometres: trees, homes, animals, railway tracks.
Looking at drone-footage of the devastation, millions of people recognised, perhaps for the first time in decades, the dark side of a sector fundamental to our era but nearly invisible: mining. Two years later, the families of the nearly 270 victims, many of whom were employed by the same mining facilities, still want justice. While the judiciary tries to ascertain criminal responsibility and discussions of compensation are underway, the technical reports are already available. These reports leave no doubt: the Brumadinho collapse was not a natural disaster, but a man-made disaster, which could have been predicted and avoided.
This disaster is perfectly in line with the mining cycle. It is the outcome of decades of poor land management, forgetfulness, and unheeded warnings.
Just three years earlier, a few dozen kilometres away, the Minas Gerais were hit by a similar disaster, though even greater in dimension. The mineral being extracted was the same – iron – as was the company owner – multinational Vale SA. An unprecedented deluge (40 million cubic metres) washed over more than 200 km of Rio Doce, submerging the Mariana habitat and causing perhaps the greatest environmental disaster in Brazil’s modern history.
In 2008 it was a containment dam in the Taoshi iron mine in China which collapsed, killing at least 250 people. Other incidents of similar magnitude have hit China in recent years, as well as the Philippines, Myanmar and Canada.
Europe no safer
While in recent years the countries most affected are developing ones, and the companies are relatively young, Europe is anything but safe from such disasters. In Romania the dams of the Baia Mare gold mine collapsed, releasing tons of cyanide into the Danube basin, poisoning a large part of it. Ten years later in Hungary, a similar incident cost the lives of ten people.
In 1985, the village of Stava in the Italian Alps was destroyed by fluorite mining waste in one of the most serious mining disasters in recorded history, caused by managerial neglect, which put profits before safety. An even worse incident occurred in Bulgaria in 1966, when mining waste swamped the town of Zgorigrad. Despite the efforts of the regime in power to minimise the disaster, today the staggering magnitude of the tragedy is well-documented: at least 488 victims.
The collapse of tailing ponds killed at least 2900 people in the last century. The environmental damage, due primarily to the extensive contamination of the soil and water, has already lasted generations.
As high as one hundred metres, and often kilometres long, the structures containing tailings dams are among the largest structures ever made by man, and also among the most dangerous. Yet their operation, if not their very existence, is virtually unknown to those who don’t work there, or live in their vicinity.
In many active mines, the enormous quantity of material extracted is reduced to a pulp and then immersed in water, inside reservoirs enclosed by earthen dams. Time, weight measurements, chemical treatments, and more or less sophisticated machinery contribute to the separation of metals and minerals of economic value (a small fraction) from the waste material. As the process continues the pond is filled, and sometimes it is necessary to raise the level of the dam. New dams are often required, built with other waste material, often upstream from the previous dam, supported by already deposited waste. These are “upstream dams”, the most widespread and also the most dangerous, especially when poorly designed.
Tailing dams can all too often be treated as provisional structures, even though they are typically used for several decades, expanding at a pace more dependent on the market than geology. It is believed that there are around 30,000 of these structures around the world, 12,000 of which are in China. Following far behind is the United States. The majority of serious incidents, but not all, occur in the active dams (a little over half of the total).
The logic of disaster
Lindsay Newland Bowker lives on a small is