The Samarco dam breach is Brazil’s largest mining-related disaster and impacted 424 miles (approximately 680 kilometers) of river, wetlands, housing and surrounding lands in the States of Minas Gerais and Espírito Santo, Brazil. Impacts extend from the mountainous region of Minas Gerais to the Atlantic Ocean in Espírito Santo.
A total of approximately 44 million cubic meters of iron mining tailings was released into the Rio Doce Basin. Over 806 buildings and 19 lives were lost to the disaster, resulting in criminal charges and a R$20 billion reais conduct adjustment agreement (TAC) towards the responsible parties. Four townships suffered most of the damage: Bento Rodrigues, Paracatu de Baixo, Gesteira and Barra Longa, with each being largely destroyed.
Impacting imperilled ecosystems
The disaster occurred within the Atlantic Forest, which is one of the most imperilled ecosystems in the world with over 93% having been lost as of 2008. The Atlantic Forest is home to approximately 264 species of mammals, 1,000 species of birds, 750 species of reptiles and amphibians and 23,000 species of plants.
Damage caused more than 400 miles away
While the larger sediment particles were trapped by the Candonga hydroelectric dam 76 miles (120 kilometers) downstream of the dam failure, sediment containing finer particles was transported over the remaining riverine system to the Atlantic Ocean more than 400 miles away, impacting marine life including rare coral communities and causing algal blooms from the increased sediment load.
Remediation, restoration and compensation
Following the disaster, the Renova Foundation was created as a result of the conduct adjustment agreement to oversee the implementation of remediation, restoration and compensatory measures. Ramboll entered into an agreement with the Public Federal Prosecutors Office to evaluate and monitor Samarco’s commitment to repair the infrastructure, restore the environment, and compensate the communities for the economic and social disruptions caused by the collapse of the Fundão Dam.
Creating resilient restoration solutions
Ramboll’s role and objectives are to help create more resilient social, economic, and environmental parameters that protect the Rio Doce Basin from future disasters. Our work is helping repair the ecological, social, and economic infrastructure damaged by the disaster as well as guaranteeing governance throughout the process. We are also developing and implementing environmental and social indicators to verify the long-term recovery of the Rio Doce Basin.
Digital solutions for public accessibility
Over the last three years, Ramboll has produced thousands of pages of technical reports from the site. In order to make the information publicly available and accessible, Ramboll took on the challenge of compiling and entering all this information into an interactive web page. Using Power BI dashboards, experts extracted and categorized huge amounts of information and transformed it into interactive graphics and maps. Users can navigate through time and space - tracking data back from the past three years and selecting geographies of interest. https://auditoria-riodoce.ramboll.com/
The revegetation efforts are divided into two sections: riparian/riverine efforts and compensatory springs. Riparian efforts are currently focused on the area between dam breach and the Candonga powerplant (approximately 4,942 acres or 2,000 hectares). Most of the revegetation is currently focused on woody species, either through transplanted containerised materials or through natural regeneration.
While replanting efforts are nascent, progress is being made through innovative cultivation and beneficial soil inoculation techniques to increase biodiversity, ecosystem recovery and long-range resiliency.