An engineer says the Samarco iron ore mine in Brazil, jointly run by BHP and Vale, was told about “severe” structural problems in one of its dams a year before it collapsed.

According to a report in the Wall Street Journal, engineer Joaquim Pimenta de Ávila in September 2014 inspected a crack in its the waste-storage facility while working for Samarco.

He recommenced the mine increase monitoring and reinforce the dam with a buttress.

Pimenta de Ávila spoke to the Journal after a statement he gave to the police in December was published by a local newspaper.

So far, 17 people have been confirmed dead from the waste dam collapse in November which sent a wall of mud downstream. The dead include five members of a village and 12 people who were working on the dams. Two are still unaccounted for.

The federal and state governments in Brazil have taken the Samarco iron ore mine, BHP and Vale to court seeking clean-up costs and damages.

The action demands a fund of BRL 20 billion ($A7 billion). BHP’s share would be half that, about $A3.5 billion.

BHP shares have been hammered since the disaster, dropping to GFC levels, though falling iron ore and crude oil prices have also taken a toll. Shares in the world’s biggest miner closed today at $14.63, down from a year high of $31.

There’s more here.

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