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2 Two Recent Catastrophic Tailings Dams Accidents
Fig. 2.2 Samarco’s Fundão dam failure flood. Photo Senado Federal
2.2.1 External Investigation Review Panel
Samarco and its owners, BHP Billiton Brasil and Vale, jointly engaged a law firm
to coordinate an external investigation into the immediate cause of the breach of
the Fundão tailings dam with the stated purpose of providing a detailed technical
understanding of the immediate cause of this failure. To carry out this work, the
Fundão Tailings Review Panel (Fundão Panel 2016) was formed, composed of four
geotechnical engineers who were specialists in water and tailings dams “…to provide
its independent and unbiased professional judgment and expertise in determining the
immediate cause(s) of the incident.”
“The Panel systematically identified and evaluated multiple causation hypotheses.
It further imposed hypothesis testing by means of the following three questions that
the candidate failure mechanism was to be able to explain:
1. Why did a flowslide occur?
2. Why did the flowslide occur where it did?
3. Why did the flowslide occur when it did?
Forensic methods adopted by the Panel integrated multiple lines of evidence: observations from eyewitness accounts; data and imagery in Geographic Information System
(GIS) format; field evidence from subsurface exploration by the Panel and others;
advanced laboratory testing; and sophisticated computer modelling. Responding to
the above three questions for hypothesis testing demanded a high level of quantifi-
2 Two Recent Catastrophic Tailings Dams Accidents
Fig. 2.2 Samarco’s Fundão dam failure flood. Photo Senado Federal
2.2.1 External Investigation Review Panel
Samarco and its owners, BHP Billiton Brasil and Vale, jointly engaged a law firm
to coordinate an external investigation into the immediate cause of the breach of
the Fundão tailings dam with the stated purpose of providing a detailed technical
understanding of the immediate cause of this failure. To carry out this work, the
Fundão Tailings Review Panel (Fundão Panel 2016) was formed, composed of four
geotechnical engineers who were specialists in water and tailings dams “…to provide
its independent and unbiased professional judgment and expertise in determining the
immediate cause(s) of the incident.”
“The Panel systematically identified and evaluated multiple causation hypotheses.
It further imposed hypothesis testing by means of the following three questions that
the candidate failure mechanism was to be able to explain:
1. Why did a flowslide occur?
2. Why did the flowslide occur where it did?
3. Why did the flowslide occur when it did?
Forensic methods adopted by the Panel integrated multiple lines of evidence: observations from eyewitness accounts; data and imagery in Geographic Information System
(GIS) format; field evidence from subsurface exploration by the Panel and others;
advanced laboratory testing; and sophisticated computer modelling. Responding to
the above three questions for hypothesis testing demanded a high level of quantifi-