REVEALED: Records show dozens of changes in Mineração Rio do Norte (MRN) tailings dams in Pará and communities fear disasters

Mineração Rio do Norte, controlled by a pool of large global mining companies and now led by Swiss trader Glencore, is Brazil’s largest producer of bauxite, the raw material used to make aluminum. It is located in Oriximiná, Pará, a municipality larger than Portugal, on the border with Roraima and Amazonas and within the Saracá-Taquera National Forest.

MRN’s annual production of 12.5 million tons of bauxite, exported to three continents, however, depends on a huge complex of 29 tailings dams that raises suspicions and generates fear in the quilombola and riverside communities close to the mining company’s operations.

New information obtained via the Freedom of Information Act (FOIA) by Mining Observatory shows that, since 2017, several MRN dams have had their Potential Associated Damage (DPA) and Risk Classification (CRI) changed in the National Mining Agency (ANM) system.

There have been an impressive 50 changes to the information provided over the last few years, which raises doubts about the reliability of the data, the inspection and the safety of the structures. Access all the changes to Mineração Rio do Norte’s DPA and CRI (in Portuguese).

The list of MRN dam upgrades (expansions), also unpublished and obtained by Mining Observatory, shows that some of the mining company’s dams underwent using upstream method, the least safe method used in Mariana and Brumadinho dams, and then “centerline” or “single stage”, which are considered safer. See the full list of construction methods (in Portuguese).

The information is extremely relevant as it reveals, for the first time, how the structures have undergone changes in recent years and that the mining company’s narrative to the communities has several problems.

“The mining company did everything it could not to include us in the study so that it could say that there is no risk of a member of the community dying or being harmed if a dam collapse,” says Guilherme Gemaque, 44, who has lived in the riverside community of Saracá since he was born and knows well how MRN deals with local leaders.

An analysis of MRN documents from recent years, such as the frequently updated PAEBM (Emergency Action Plan for Mining Dams), the Dam Break, hypothetical rupture studies and environmental impact studies for the various dams and the expansion of the project in Oriximiná, also shows a huge variation in whether or not the risks posed by the dams to the communities are recognized.

This is the case with the impacts on the Boa Vista Quilombo, in the 2018 and 2020 PAEBMS for the Água Fria and A1 dams, and on the riverside communities in the case of the TP1 and TP2 dams, analyzing the 2018 PAEBM and the 2021 hypothetical breach studies.

Communities are gradually being rendered invisible in MRN’s studies, with significant differences in the way potential risks and impacts are recognized or not, and the absence of necessary emergency measures in the event of a rupture was noted in the most recent studies.

All photos by Carlos Penteado / CPI-SP

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MRN says dams are safe. Leaders and researchers have doubts.

Asking for comment, MRN said that its tailings dams are safe and that it complies with all the requirements of the law with regard to the company’s Emergency Action Plan for Mining Dams (PAEBM). In addition, MRN says that it “respects and has permanent channels for dialog with the communities surrounding the project”.

The National Mining Agency said it is finalizing reports on MRN’s dams from an inspection carried out in August 2023.

“If a dam collapse, I can say with certainty that there is a risk of human death,” says Gemaque, who says that MRN takes water to wash bauxite from the nearby streams. “There’s nowhere to run, I’m going to sink in the flooded areas. I have no siren alert in the community, no direct communication with the company,” he says, fearing that something similar to Mariana and Brumadinho could happen in Oriximiná.

According to Guilherme Gemaque, a project was drawn up in 2019 to set up escape routes and meeting points. When everything was ready, however, the mining company fired the person responsible for the meetings, which were canceled due to the Covid-19 pandemic. When they returned in 2022, the discourse had changed.

“I cried when I heard the mining company say that it had no obligation to provide information to the communities because, according to the study, there was no risk of the dam breaking. I felt very sorry because I’ve lived here for 44 years and I know how Saracá was and how Saracá is today. We used to have crystal-clear water, today it’s not what it was. We understand that there is a risk, although according to the study we are outside the flood wave. There’s no way a dam can break and not hit Saracá,” says Gemaque.

According to MRN, in 2021, new dam break studies were carried out by independent consultants, which showed that in the scenario simulating the rupture of the Água Fria and A1 dams, there would be no community house within the Self-Rescue Zone (ZAS). As a result, the PAEBM (Emergency Action Plan for Mining Dams) was adequate and there was no need for any community members to leave their homes during the practical simulation of a mining dam emergency.

MRN also claims that it is “unaware of any episodes of contamination of watercourses that may be impacted by its operations”. Read the full response from the mining company (in Portuguese).

Researcher Klemens Laschefski, from the Federal University of Minas Gerais (UFMG), who holds a PhD in Geography, closely follows the strategies used by mining companies to manage dams. For the professor, there is a chronic problem of too much power in the hands of the companies and too little oversight by public bodies.

“Companies in general are using what we call dam terrorism, the issue of safety, as a means to support their own interests. Nobody charges for an independent study on the risk of dams, the mining companies themselves do the studies. And the environmental agencies release licenses for anything,” says the specialist in Political Ecology.

Carlos Penteado / CPI-SP

Gaps in studies and in the mining company’s discourse raise questions

According to Guilherme Gemaque, the constant changes in employees make it difficult for people to trust MRN’s assessment. In addition, he says, past meetings have acknowledged that the Saracá community was at risk and that the dams were built upstream.

“Why do they say we’re not at risk? Because they don’t want to guarantee anything. They don’t want to commit to the families. I ask why the study changes from one moment to the next when the community is the same, the place is the same, the dams are the same and the mining is the same. How can this study change from one year to the next? In addition, we used to hear a lot that the dams were upstream, today they don’t use that expression anymore. So why does it change from one hour to the next?” asks Gemaque.

In a preliminary analysis of MRN’s studies carried out at the request of this report, engineer Euler de Carvalho Cruz, who holds a master’s degree in metallurgy, warns that the scenario of heavy rainfall considered in MRN’s document is “extremely questionable” due to climate change.

“All the criteria for what we call ‘extreme rainfall events’ need to be reviewed. Today’s world is a different place, with droughts and extreme rainfalls that have never been seen before. The dam break study was based on data from a bygone era. We are in an unknown world,” says Euler.

According to the engineer, when he notes that MRN’s study states that the hypothesis of dam failure due to liquefaction is “ruled out” and “not credible in any scenario”, it is necessary to investigate why this would not be possible. Liquefaction was the rupture mechanism responsible for the Mariana in 2015 and Brumadinho in 2019.

“The word ‘credible’ is not technically appropriate, because it’s not a question of believing it or not. A technical document cannot refer to beliefs, but to probabilities. If liquefaction is impossible, the probability is zero,” says Euler.

Carlos Penteado / CPI-SP

Slow adaptation to climate change causes concern

Domingos Gomes, a resident of the Boa Nova community, worked for MRN for a few years. According to his assessment, the mining company’s relationship with the community has never been good, bauxite waste affects the water used by the communities and there is a lack of monitoring of the impacts of operations within the Saracá-Taquera National Forest. The reality, he says, is ignored by MRN.

“Their studies don’t match our reality. We have experience, we live in the forest, in the igarapé, we can see any impact. Just by not being able to catch fish to eat, not being able to bathe in the river, we are already affected. The company has done nothing for the communities so far. It’s just leaving an impact”, he says.

For the former MRN employee, climate change is a reality that cannot be ignored. “The dams are on top of the Saracá plateau and this is a concern, especially in the rainy season, because the climate is changing and we have a very large volume of water”, he says.

Asked how it is requiring companies to adapt to climate change and increase the safety of their dams, National Mining Agency said that the technical aspects relating to the hydrological and hydraulic safety of mining dams are addressed in the current regulations – ANM Resolution No. 95/2022 – following the best international practices.

“The effects of climate change on heavy rainfall patterns and on the performance of dams and attached structures will have to be gradually incorporated and addressed with the mandatory periodic reviews for all structures. The ANM will continue to monitor compliance or non-compliance with the obligations set out in ANM Resolution No. 95/2022 and will act, within its competence and institutional capacity, to ensure the proper safety management of mining dams throughout the national territory. Article 24 of ANM Resolution No. 95/2022 stipulates that overflow systems must be adapted to return times by 12/31/2023,” said the agency.

This “return time” can be up to 10,000 years or by the PMP (Probable Maximum Precipitation) in the case of high Associated Potential Damage, whichever is more restrictive. “The flow capacity of the reservoir spillway, according to the expected return time, must be reassessed based on the available rainfall and flow data from the reservoir’s hydrographic basin, considering the uncertainties of the maximum design flow studies,” says the resolution.

MRN said that “in 2023, in conjunction with the consulting firm Pimenta de Ávila, MRN developed a study of the influence of climate change on intense rainfall in the MRN region and its surroundings, and the results will be considered in its operation and related projects”.

While mining companies are gaining time to adapt and control the information provided about the safety of their structures, the rainy season in the Amazon, which began in last November, is causing more concern for residents of affected communities, as is the case in Oriximiná.

Insufficient compensation and protocol consultations

Maria Expedita, 60, an educator, has lived in the Boa Nova community for over 20 years, where she also works as a coordinator. For her, the fear that the dams cause is a constant. “I’m afraid that something might happen with the dams and all the communities are. We get worried,” she says. 

But the problems with MRN go beyond the possibility of the dams collapsing or not. The reality is the contamination of the region’s watercourses and compensation actions such as families having to spend all day collecting predetermined seeds in minimum quantities of 1 kilo each in order to receive R$350 (around $ 70) at the end of the month. In practice, the mining company does what it wants and is not penalized.

“The reserve was ours, they took it over, promised and didn’t deliver. They leave giant plastics in the forest, take out wood, let it rot and aren’t fined,” says Expedita. The educator also criticizes the way in which MRN’s expansion, the so-called “New Mines Project”, which aims to extend bauxite exploitation until 2042, is taking place.

For her, the mandatory public consultations are a mere formality. “I don’t think it will benefit any community. Everything has already been decided and authorized. The hearings are just protocol,” she says.

When questioned, Ibama said only that it “carried out a technical inspection in May this year at the New Mines Project (PNM), on the occasion of public hearings held as part of the project” and that the PNM Environmental Impact Study (EIA/RIMA) “is being analyzed and will result in a technical opinion”.

The actions of giant companies like MRN end up disrupting the entire way of life of the communities, says Jader Gama, who has a PhD in Socio-Environmental Development from the Federal University of Pará (UFPA). “When you take a quilombola community away from its economic way of life, you make them vulnerable so that they need the so-called compensation. This game is very damaging to the organization of the community,” says the researcher.


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