Accidents don't happen - They're made

When the Fundão tailings dam failed on 5 November 2015, it unleashed about 40m litres of water and sediment from iron ore extraction in a wave that polluted the water supply for hundreds of thousands of people, decimated wildlife and spewed a rust-red plume of mud down the Doce river. Yet more than two years later, nobody has accepted responsibility. None of the 375 families who lost their homes have yet been rehoused.

Six months before the dam containing millions of litres of mining waste collapsed, killing 19 people in Brazil’s worst environmental disaster, the company operating the mine accurately predicted the potential impact of such a disaster in a worst-case risk assessment. The document – one of hundreds submitted to the court by prosecutors – warned that a maximum possible loss from a “liquification break” could mean up to 20 deaths, cause serious impacts to land, water resources and biodiversity over 20 years, and cost $3.4bn.

The Brazilian mining giant Vale and the Anglo-Australian multinational BHP Billiton – failed to take actions that they say could have prevented the disaster. The prosecutors instead claim the company focused on cutting costs and increasing production.  Company directors said: “Despite the improvements in cost reduction the world is not standing still and further improvements are needed.” 

“They prioritized profits and left safety in second place,” said José Adércio Sampaio, coordinator of a taskforce of federal prosecutors.

Almost as soon as it started operating in 2008, the dam presented problems with its drainage system and signs of erosion, according to photographs and inspection reports included in court documents. Seepage, saturation and cracking were seen at the dam in 2013, and again in August 2014, the report said. Pimenta de Ávila, a consultant, inspected the area in December 2014 and told prosecutors he had informed Samarco the situation “was not under control”. At the time of the disaster, the Fundão dam was fitted with devices used to measure liquid pressure and water level, but according to the prosecutors’ case, several were either not working, lacked batteries or had been moved to another dam. There was no warning siren. When the dam broke, residents were warned by telephone calls or – in Quintão’s case – by a neighbour who roared up on a motorbike shouting: “The dam has burst!”

https://www.theguardian.com/world/2018/feb/28/brazil-dam-collapse-samarco-fundao-mining