An analysis of Bento Rrodigues Dam Disaster for the Occupation Health and Safety module in semester 3 at the Transport & Logistics Management Honors degree program conducted in University of Moratuwa.

1. BENTO RODRIGUES DAM DISASTER
The Bento Rodrigues dam disaster occurred on 5 November 2015, when an iron ore tailings
dam in Bento Rodrigues, a sub district of Mariana, Brazil, suffered a catastrophic failure, causing
flooding and at least 17 deaths. At least 16 people have been injured.
About 60 million cubic meters of iron waste flowed into the Doce River. Toxic brown mudflows
reached the Atlantic Ocean17 days later. The total impact and environmental consequences to the
river and the beaches near its mouth, or to the wildlife are massive and as some of the scientists
have suggested it will take decades for people to use now contaminated water without any health
hazard. This incident has been described as the worst environmental disaster in Brazil's history.
The dam is a property of Samarco, a joint venture between Vale and BHP Billiton. Initially it
was speculated that the causes for the collapse would be some weaknesses in the dam's structure
that were described in a report of 2013 from the Brazilian authorities. BHP Billiton denies this
version, and the causes of the incident are still being investigated.
The full extent of the environmental damage remains unknown. Experts estimate that the region
could take 10 to 50 years to recover - if it ever does. A full environmental assessment by
independent contractors has yet to be made. According to biologist and ecologist Andrew
Ruschi, who studies marine biology at the Estação Biologia Marinha Augusto Ruschi in Santa
Cruz, Espírito Santo, the waste will take at least decades to dilute to levels anywhere near
previous levels.
The spill has polluted the 800-kilometer-long Rio Doce - the region's most important river -
killing fish, destroying ecosystems and polluting drinking water supplies. The river basin has a
drainage area of about 86,715 square kilometers, with 86% in Minas Gerais and Espírito Santo.
In total, the river covers 230 municipalities that use its bed for subsistence. 2.2 Billion cubic feet
of mining waste which included the Arsenic, zinc and copper and mercury laced mud oozed into
one of Brazil’s most important rivers, the Rio Doce, killing fish and aquatic life hundreds of
kilometers away and making the water hundreds of thousands of people depend on undrinkable.
On 7 January 2016, the waste reached the southern Bahia littoral zone. Environmentalists follow
closely the impact to the Abrolhos Marine National Park wildlife. The park is considered of vital
importance to the Brazilian ecosystem since it hosts the major marine biodiversity in the
whole southern Atlantic Ocean.

2. According to the latest models used by the environmental agencies studying the flow, the mud
plume has dispersed along the coast around six miles south of Regência, two miles north and 1.5
miles out to sea.
The area is rich in marine life, including humpback whales and La Plata dolphins, but Almeida’s
greatest concern is for the endangered leatherback turtle. The beach is one of the only regular
nesting grounds for the creature in Brazil.
With the oxygen levels in the Rio Doce drastically reduced by 50m cubic metres of mining
waste, the plant and animal life along the river has been devastated in what the environment
minister, Izabella Teixeira, described as “the worst environmental disaster in Brazil’s history”.
Fears over the presence of heavy metals and other toxins in the mud have also led ANA, the
national water agency, to suspend the use of the Rio Doce for human consumption.
Although the water supply from the river to the city of Governador Valadares has now been
restored, around 150,000 people are still reliant on deliveries of drinking water from Samarco.
The Bento Rodreguez Dam collapse has not only effected the human lives but it has also
endangered the wild life, marine life while bringing devastating environmental issues which has
been fined for $ 4.8 Billion. Although the money itself can mitigate the hazardous effects of the
disaster the long term environmental risk that it poses to the natural habitats as well as
community cannot be paid by money. Using preventive methods beforehand and careful
inspection of the potential hazards will prove to be effective and economical rather than paying
fines and purifying contaminated water after the hazards.

3. References
Independent, (November, 2016). Brazil faces environmental disaster as deadly tide of orange mud
bleeds to sea following a dam failure. Retrieved from Independent Online:
http://www.independent.co.uk/news/world/americas/brazil-faces-environmental-disaster-as-
deadly-tide-of-orange-mud-bleeds-into-sea-following-dam-a6744256.html [Accessed on 23rd
May, 2016]
Wikipedia, Bento Dam Disaster. Retrieved from Word Health Organization:
https://en.wikipedia.org/wiki/Bento_Rodrigues_dam_disaster [Accessed on 24th May, 2016]
The Guardian: Brazil’s mining tragedy: was it a preventable disaster (November, 2015).
Retrieved from: http://www.theguardian.com/sustainable-business/2015/nov/25/brazils-mining-
tragedy-dam-preventable-disaster-samarco-vale-bhp-billiton [Accessed on 24th May, 2016]
Made for Minds: Clearer picture emerging over Brazil's mining disaster (January, 2016).
Retrieved from: http://www.dw.com/en/clearer-picture-emerging-over-brazils-mining-disaster/a-
19006554 [Accessed on 24th May, 2016]
GROUP MEMBERS
14141456 X – H.N. RAHUBADDHA
14141405 R – B.R.P.P.K. BALASOORIYA
14141448 B – K.P.D.H. UDARA
14141451 D – C.K. WADUGE