THE Brazilian Senate has passed a bill to tighten dam safety, reports Reuters. This follows the collapse of a Vale mine tailings dam in Brazil on 25 January. Since the collapse, 186 people have been confirmed dead whilst 122 people remain missing.
Tailings dams are built to contain the waste left from ore processing – a slurry made of fine uneconomic rock and chemical effluent – known as tailings.
The bill, which was passed by two committees on 27 February, tightens regulations on all dam types and bans upstream tailings dams says Reuters. If it is not appealed by Senators within five working days, it will pass to the lower house for consideration.
This recent approval strengthens the decision of Brazil’s National Mining Agency (ANM) which recently announced in a resolution the decision to ban upstream dams.
The Vale dam which collapsed was built using the upstream method, which Steven Edwards, Deputy Director of the University College London Hazards Centre, referred to as “the worst”. In 2015, another upstream dam collapsed in Brazil, killing 19 people and polluting local water supplies. The dam was owned by Samarco, a joint venture of Vale and BHP Billiton.
According to Reuters, the collapse of the of the Vale dam provoked a global outcry against Vale and the Brazilian Government for allowing two similar disasters to happen in the span of a few years.
Reuters reports that the recent Brazilian bill is similar to one which failed to “gain traction” three years ago.
Senator Leila Barros, author of the new bill, reportedly told Reuters: “I am certain, if it had passed Congress with the 16 amendments and all the feedback from the environment committee, something definitely would have been done to prevent this disaster, this crime in Brumadinho.” Reuters also reports that Barros hopes for approval in the first half of 2019.
According to Reuters, the “overhaul” for the regulation of all dams – not just tailings dams – will require more advanced technology and detailed emergency plans. And the bill includes measures which would increase the legal power of government enforcers, make those who certify dam safety criminally liable, and increase the financial responsilities of operators in the event of a disaster. For example, one amendment would raise the maximum fine for dam operators to R$10bn (US$2.68bn), says Reuters.
The Vale dam which collapsed on 25 January was Dam 1 of the Córrego do Feijão mine, located in Brumadinho, Minas Gerais, Brazil.
Reuters reports that a Brazilian judge has ordered the release of eight Vale employees who were arrested on 15 February, in relation to the collapse. Since Dam 1 collapsed, Vale has said that “ it will continue to fully cooperate with the authorities, and it will continue to support the investigations in order to determine the facts.”
Vale recently announced that it was suspending operations at its Fábrica and Vargem Grande complexes due to an order by the ANM. The suspension is aimed at preventing failure by liquefaction of dams of the Vargem complex. Liquefaction is a process in which solids such as sand behave more like liquid. This process led to the collapse of the Samarco dam in 2015, and is thought to have caused the collapse of Dam 1.
Recently, Vale posted an overview of its actions since the collapse of Dam 1. The list includes humanitarian actions, emergency payments, actions related to the environment, tailings retention work, and information about the upstream dams it is in the process of decommissioning.
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