Assessing and managing safety risks to downstream communities (in hindsight): What went wrong in the licensing and impact assessment procedures of Brazil's deadliest dam breaks?

Environmental impact assessment (EIA) is a policy tool used all around the world to predict, mitigate, and manage the impacts and risks of development proposals. This tool, if well implemented and articulated with licensing procedures, can result in improvements of project design and in the prevention and mitigation of environmental and social harms. But sometimes EIA can fail, as illustrated the collapse of the Brazilian tailings dams Fundão and B1, in 2015 and 2019 respectively. Despite having gone through licensing and EIA procedures, the two dams collapsed, killing almost 300 people. This study set out to understand how the vulnerability of downstream communities to dam breaks were predicted and managed in the dams' EIA processes. This study also tried to understand whether the EIA process of a newly approved tailings dam in Brazil (Maravilhas Dam III) improved the prediction of safety risks to downstream communities. The study was based on literature reviews and a content analysis of eighty-four (84) key documents related to the dams' licensing and EIA procedures. The study found that the risk-related studies of the dams were based on a variety of methods (e.g., Preliminary Hazard Analysis, Failure Mode and Effects Analysis, Dam Break simulations, Contingency Plans) that were implemented in different phases of the licensing procedures. It was possible to identify several flaws and limitations in these methods, such as vagueness, late implementation, fragmented reviews of interdependent risks, and low influence on decision-making. Both the Fundão and B1 dams were approved despite the lack of in-depth and up-to-date risk assessments. Public consultations were generally weak and plagued by tokenism. Post-approval procedures, while informed by monitoring, audits and inspections that confirmed problems in the dams, were unable to educate developers and State authorities about the likelihood of failures and the safety risks to communities. Overall, the Fundão and B1 cases show the importance of not only predicting but also managing risks in a timely, transparent and articulated manner. The Maravilhas III Dam, compared to Fundão and B1, was found to have sounder evaluations of safety risks and stronger public participation. The regulatory and voluntary frameworks concerning tailings dams have improved in recent years. The projects of Fundão and B1 could not receive an environmental license had they been subject to the current Brazilian legislation, because they proposed a now-banned technology (upstream dams) and had vulnerable communities located in self-rescue zones, which is now legally unacceptable. Despite these regulatory changes, there is still room to improve regulations, guidelines and Terms of References for risk analysis and its articulation with impact assessment and public participation. The article discusses the academic implications of the cases to international audiences and put forward several practical recommendations.