This is fucking huge. Like a mind boggling huge fine. The scale of the disaster was unbelievable, and it was pretty clear they ignored a shit pile of red flags before it happened.

From wiki:

The Mariana dam disaster, also known as the Bento Rodrigues or Samarco dam disaster, occurred on 5 November 2015, when the Fundão tailings dam at the Germano iron ore mine of the Samarco Mariana Mining Complex near Mariana, Minas Gerais, Brazil, suffered a catastrophic failure, resulting in flooding that devastated the downstream villages of Bento Rodrigues and Paracatu de Baixo (40 km (25 mi) from Bento Rodrigues), killing 19 people.[4][5] The extent of the damage caused by the tailings dam collapse is the largest ever recorded with pollutants spread along 668 kilometres (415 mi) of watercourses

The failure of the dam released 43.7 million cubic metres of mine tailings into the Doce River, causing a toxic brown mudflow to pollute the river and beaches near the mouth when it reached the Atlantic Ocean 17 days later.[7][8][9][10] The disaster created a humanitarian crisis as hundreds were displaced and cities along the Doce River suffered water shortages when their water supplies were polluted.

And ignoring of red flags:

January 2016, the leaking of internal documents from 14 months before the disaster revealed that Samarco had been warned about the possibility of the dam collapsing.[24] Joaquim Pimenta de Ávila, an engineer who was regarded as one of the foremost tailing dam engineers in Brazil, had been contracted by Samarco between 2008 and 2012 to design and oversee the construction of the Fundão dam. From 2013, Ávila was hired part-time as a consultant to inspect the dam, and a technical report he wrote from September 2014 lists severe structural problems on the dam (in the form of cracks) and measures to mitigate them, the main one being the construction of a buttress. Samarco claimed to have implemented all the recommendations from Ávila, and that the dam was in the process of being heightened when the impoundment reached its maximum holding capacity and began to leak. However, Samarco failed to comment specifically about the buttress, and claims that it was never warned about the severity of the structural damages, nor about the imminence of a catastrophic failure.