A press conference was held this Monday, 29, in Belo Horizonte (MG), Brazil, to deliver the results of the independent investigation that was requested by Samarco and its shareholders, Vale and BHP Billiton regarding the accident at the Fundão dam on November 5th, 2015. Vale’s CEO, Murilo Ferreira, Samarco’s President, Roberto Carvalho, BHP Billiton’s Commercial Director, Dean Dalla Valle, and the leader of the investigation’s panel, Norbert Morgenstern, attended the conference.
The investigation was conducted by law firm Clearly Gottlieb, which formed a panel of four of the best geotechnical experts in the world. Norbert Morgenstern, the leader of the panel, has worked on more than 140 dam projects and has more than 330 academic papers published on the subject. He acts as a member, Vice-President and President to an extensive list of technical committees all over the world, in addition to contributing to the transfer of technology to developing countries via the United Nations and other agencies. The panel also included Klohn Crippen Berger Ltd.’s Counsel Chairman and former CEO, Bryan Watts, who has over 35 years of experience on dam projects. Steven Vick, the third member of the panel, is an author and independent consultant in geotechnical engineering, with over 40 years of experience acting in technical and safety assessments for landfills and tailings dams. Completing the team of experts, Cassio Viotti is an independent consultant in dam engineering, with over 45 years of experience, specialized in all stages of dam and hydric structure conception and engineering.
They have assessed the technical aspects that caused the dam to fail and conducted extensive tests. Throughout the investigation, the company had unconditional access to all Samarco’s documents, and to documents related to its employees and facilities.
The technical assessment included, among other aspects, the building of a 3D computer model of the tailings facility showing movement over time; an in-depth analysis of tailings deposited in the Fundão dam to understand their properties and behaviors; an overtime analysis of the saturation levels of the dam and the water running by it; and tests to understand the role seismic activity could have had in the structure’s collapse.
The panel applied hypothesis tests to find answers to the following questions:
- 1. Why did a fluid stream of tailings occur?
- 2. Why did this fluid stream of tailings occur where it did?
- 3. Why did this fluid stream of tailings occur at the time it did?
The investigation concluded that the dam ruptured as a consequence of a chain of events and conditions.
Watch the replay of the press conference