More toxic material confirmed on Tiwai aluminium smelter site

Friday, 30 April 2021

Stew Hamilton, chief executive at the New Zealand Aluminium Smelter (NZAS) smelter at Tiwai Point, near Bluff.

The amount of a toxic substance stored on the Tiwai Point aluminium smelter site is 217,000 tonnes, up from the previously reported 181,000 tonnes.

NZAS chief executive and site general manager Stew Hamilton said independent auditors confirmed the adjusted totals of the spent cell lining [SCL] following a survey of the site as part of the smelter’s annual financial reporting process.

“We want to make sure the community is aware of the adjusted quantity,” Hamilton said.

NZAS decided last year to extend its stay at the smelter site until 2024.

But Hamilton repeated on Friday that the company remained committed to removing all SCL, a hazardous waste generated by the aluminium smelting industry which contains concentrations of fluorides and cyanides.

He said financial provisions had been increased to ensure the responsible management of all SCL material stored onsite.

“I want to be very clear that regardless of the amount, we remain committed to removing all of the material from the site to be recycled or disposed of safely and securely in accordance with modern standards.”

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The increased amount of SCL onsite would not impact on the timeline for removal, he said.

“The material is secure and safely stored, as confirmed by Worksafe inspectors during their visit in February.”

NZAS continued to conduct regular and extensive environmental monitoring of the site and recently released assessments of the groundwater surrounding the SCL storage facilities.

Hamilton said he was confident its environmental monitoring systems gave it ample warning of any issues and enabled it to remediate or alter processes to halt any breaches becoming harmful.

There had “never been an instance” during the plant’s 50 years of operation which could harm the public or local communities, Hamilton said.