Upstream Dam De-characterization Program in Brazil
Vale's priority is the safety of people and communities downstream of its operations, as well as the safety of all its structures. In this sense, one of the company's main initiatives is the Upstream Dam De-Characterization Program, which covers all our 30 dams, dikes, and drained piles in Brazil with upstream heightening method.
Under the upstream heightening method, the body of the geotechnical structure is built from the thick tailings deposited in the reservoir, by successive stratification and in the opposite direction to the flow of water (upstream). This is the same construction method used on the collapsed dam in Brumadinho.
What is de-characterization?
The term ‘‘de-characterization’’ means to functionally reintegrate the structure and its contents into the environment, so that the structure no longer serves its primary purpose of acting as a tailings containment. Laws and regulations approved in Brazil following the rupture of Brumadinho dam require the de-characterization in all our upstream dams on a specified timetable. Due to the technical complexity involved in the de-characterization works and the necessary actions to increase safety of the structures, in February 2022, we have entered into a term of commitment with the state of Minas Gerais, regulatory agencies and state and federal public prosecutors, establishing a new schedule and reinforcing the commitment to eliminate all its upstream structures in Brazil. We are still determining the appropriate measures for the de-characterization of certain upstream dams in Brazil.
Program evolution
Among the 30 structures contemplated, 13 had works completed up to now. The de-characterized are:
**Reconformation of the dam massif in a single step underway
The company expects to complete its Upstream Dam De-Characterization Program in Brazil by 2035, according to the synthetic schedule below.
Schedule of the Upstream Dams De-characterization Program in Brazil
Elimination of Upstream Dams per Year (unit)
Vale emphasizes that the deadlines proposed above are based on the best information and techniques available at the time. They can be adjusted based on a relevant fact or condition that appears, in particular, related to the safety of the de-characterization process.
Resources for the de-characterization of upstream dams
Situation of imminent or ongoing rupture.
Comunication to:
the ANM, environmental agencies, Civil Defense (national, state and municipal), ZAS and ZSS.
Vale’s structures
Immediate actions: Care is extended to people who are in the ZSS through additional educational measures.
Dams: B3/B4, Forquilha III, Sul Superior.
Technical Reports
In compliance with the Term of Commitment for De-characterization signed with the main regulators and the Public Ministry, Vale makes available the monitoring reports on the execution of the de-characterization works of its upstream dams:
