Pollutant releases: Rio Tinto's Arvida aluminum smelter under investigation

< /p> UPDATE DAY

The Ministry of the Environment is investigating breaches of atmospheric emission standards at Rio Tinto's Arvida aluminum smelter in Saguenay, our Bureau of Investigation has learned.

“A criminal investigation is currently underway for exceeding atmospheric emission standards and in order not to interfere with the criminal process, the [ministry] must limit its comments on this subject,” confirmed the communications directorate of the ministry of l. 'Environment.

The investigation targets source emission exceedances for particles and fluorides that occurred in April 2022 and for which a warning (notice of non-compliance) was already sent in July 2022.

The file will then be transferred to the Director of Criminal and Penal Prosecutions, who will determine whether statements of offense should be filed. If Rio Tinto, which owns the plant, were found guilty, it could face hefty fines ranging from $30,000 to $6 million.

The Arvida plant, older and polluting than the modern aluminum smelters, already enjoys more permissive standards for its particulate and fluoride discharges, but it does not always manage to comply with them. In 2017, she had to pay $10,000 in penalties for failing to meet monthly particle limits. 

In addition, its ministerial certificate (of the same type as that of the Horne foundry in Rouyn-Noranda) grants it less stringent standards concerning the particles in the ambient air which are measured near the plant. 

Its particle and fluoride standards have been set to be tightened for 10 years, but the plant has managed to obtain a postponement three times despite public health concerns. However, Rio Tinto had committed to making significant investments.

Public health concerned

In 2017, the Deputy Director General for the Protection of Public Health at the Ministry of Health, Yves Jalbert, supported by the National and Regional Public Health Department, asked a tightening of standards for the Arvida plant. The population's exposure to fine particles (PM 2.5), of which the plant is the largest emitter in Quebec, was also considered “worrying”.

In its impact analysis dated 2020 to allow the plant to continue its operations, even the ministry acknowledged that “the activities of this part of the plant are […] associated with poor quality of the air in inhabited areas near the plant.” 

Questioned by Le Journal about its environmental record, the company insisted on the improvements of the last years. “We have made investments of $30 million since 2018 to modernize the Arvida plant purifiers, in order to meet three voluntary commitments that have led to reductions of around 10% in fine particle emissions,” explained Malika. Cherry, public relations advisor for the aluminum smelter. 

We have discovered that this decrease is much less.

Rio Tinto has technically until the end 2025 to modernize its equipment, but it now wishes to obtain a fourth postponement of the tightening of its standards, revealed Radio-Canada, these days.

➤ Consult our interactive map to find out about the biggest polluters in Quebec as well as the air quality in their regions.

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