Vale’s plan to decommission Mariana and Brumadinho-style dams

Last Friday’s catastrophic dam failure near the town of Brumadinho, Minas Gerais, has left at least 99 dead and, so far, 257 missing. Although the concrete cause of the collapse is not yet known, Brazilian society is pointing its finger directly at the company in charge: the country’s biggest mining company, Vale. A co-owner of the dam which failed in the nearby town of Mariana in 2015—causing the biggest environmental disaster in Brazilian history—Vale will be forced into taking action this time around.

There were calls for the Vale board of directors to be sacked, while Brazil’s Prosecutor General Raquel Dodge has talked about making the officers criminally liable. In response to the mounting pressure, Vale has announced it will decommission all of its tailings dams which use the same structure as those in Brumadinho and Mariana, highlighted by experts as being a potential cause for the two catastrophic failures over the past three years.

The dam in Brumadinho was raised using what is called an...