Vale to Investigate Nitrous Oxide Leak at Northern Ontario Nickel Smelter

   By Jane Gerster 
 

Brazilian mining giant Vale S.A. said Thursday it would conduct an internal investigation into a nitrous oxide leak that occurred early in the day at its nickel smelter in northern Ontario.

Vale said it declared a level-three emergency around 6 a.m. local time after the leak, which resulted in a yellow plume above the area, but has since downgraded the emergency level.

The leak occurred in the acid plant of the company's Sudbury, Ontario nickel smelter. The plant was closed at the time of the leak for scheduled maintenance, Vale said.

Vale has a refinery, six mines, a mill and a smelter in Sudbury.

Following the leak, local police said they blocked off nearby roads and warned residents to stay inside and turn off air intake devices such as furnaces and air conditioners. Nitrogen dioxide, which affects the respiratory system, can be fatal in large doses.

Police have now lifted road closures and Vale said the mist resulting from the leak had dissipated. It said there is no risk to the community and that no injuries have been reported as a result of the incident.

Write to Jane Gerster at [e-mail]

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