The real human cost of the 'catastrophic' BHP mine disaster.

“The mud would come and drag me down, I would come up, it would take me down again… I screamed, calling my children, calling them, but nobody answered.”

This is the real, human cost of the mudslide that ravaged the small village of Bento Rodrigues in Brazil three months ago. As ABC Four Corners presenter Ben Knight discovered, the devastation is widespread.

When a dam holding back more than 50 million cubic metres of mining waste from the Samarco iron ore mine collapsed, it sent a wave of mud hurtling through the towns and villages of Brazil’s Gualaxo River Valley.

Watch a snippet of tonight’s Four Corners episode below (post continues after video).

The mine is half owned by Australia’s BHP Billiton. According to the ABC, Brazil’s chief environment officer called the collapse and resulting mudslide the biggest environmental disaster in the country’s mining history.

Homes, roads and towns were destroyed.

“I ended up with nothing but the clothes I had on,” said one survivor. “I lost everything I had at home, documents, photos of my children.”

Nineteen people lost their lives.

BHP CEO Andrew Mackenzie said “Of course it will affect our bottom line.” This week, the company announced a $US5.7 billion half year loss. More than one billion dollars has been put down to the dam disaster. The company have since distanced itself from the operations of the mine, but Brazilian police are seeking the arrest of six executives and managers involved. Their charges include negligent homicide and offences against the environment.

Four Corners investigated whether multiple warning signs were ignored. What Knight finds is a catalogue of failure, where even the emergency alert system didn’t work.

“A dam doesn’t break by chance…” said the Brazilian prosecutor. “There is repeated, continual negligence in the actions of a company owned by Vale and BHP.”

According to Four Corners, the problems at the BHP-owned dam date back to its construction in 2007. Furthermore, independent testing of water samples from the river system found levels of arsenic 10 to 20 times higher than Brazilian regulations allow.

Now, state police say the disaster was in part caused by a ramp up in production to counter the falling iron ore price.

The Brazilian government is potentially looking to claim $7.2 billion for the damage, piling another bill on top of BHP’s hefty debt.

Catastrophic Failure, reported by Ben Knight and presented by Sarah Ferguson, will be replayed on Tuesday 1st of March at 10.00am and Wednesday 2nd of March at 11pm. It can also be seen on ABC News 24 on Saturday 5th March at 11.00pm, and on ABC iview and at abc.net.au/4corners.

Feature image: Supplied/ABC