Brazil’s National Mining Agency (ANM) has orderd a halt on 47 iron ore mining dams that failed to certify their stability.
These dams belong to ArcelorMittal Mineração Serra Azul, and the B2 Auxiliar dam, of Minérios Nacional, which belongs to the group Companhia Siderúrgica Nacional among others. However, 25 of the 47 dams belong to Brazilian miner Vale.
ANM pointed out that Vale’s Norte/Laranjeiras dam, which is part of its Brucutu mine also failed to show stability. Vale had said recently that it was testing short- term alternatives for disposing tailings from this mine, which may increase its output capacity from 40 to 80pc.
Vale did not respond to Davis Index’s query on how its production would be impacted by the suspension of operations at these 25 dams.
However, a spokesperson at ArcelorMittal Brazil told Davis Index that contrary to some media reports the company did not receive a notice of interdiction from ANM for its Serra Azul mine’s tailings dam during the agency’s campaign to deliver the Declaration of Stability Condition (DCE) in March 2020.
The Serra Azul dam will not impact the mine’s operation and production, the spokesperson said, adding that the tailings dam was idled in 2012 and does not receive any tailings since all tailings produced by the mine are now disposed by using the dry stacking method.
The safety conditions of Serra Azul Mine’s tailings dam remain unchanged since February 8, 2019, when the emergency level of the dam was raised to Level 2 and the company decided to restrict access to the area of the dam.
According to ANM, of the 431 tailings dams currently included in Brazil’s National Dam Safety Policy (PNSB), certifications for stability were forwarded for 384 dams. Around 31 of these submitted a declaration not certifying the stability of the structures and 16 did not send documentation, which presupposes they do not have the stability of the certified structure.
Brazil’s Minas Gerais state has the largest number of closed dams (37), followed by Mato Grosso (4), Paraná (2), São Paulo (2), Amapá (1) and Rio Grande do Sul (1), ANM said.