Ngāi Tahu sign agreement to clean up whenua at Tīwai Point

By Tumamao Harawira

Ngāi Tahu is working on ways to restore the Tiwai Point aluminium smelter in Southland.

It has teamed up with mining giant Rio Tinto and its New Zealand subsidiary, NZ Aluminium Smelters, to explore ways to reinvigorate the area once the smelter closes in just over two years' time.

The iwi and representatives of Rio Tinto and NZ Aluminium Smelters signed an agreement at Te Rau Aroha marae in Motupōhue, Bluff. It involves the iwi working alongside Rio Tinto to remove waste, conduct environmental monitoring, and restore the site.

Dr Mike Stevens from Te Rūnanga o Awarua, which is a papatipu rūnanga of Ngāi Tahu, says it is an area of great significance for Māori.

"The site was one of the earliest for producing adzes, within 100 years of the Polynesian discovery of Aotearoa, Te Waipounamu. So, it's really one of those sites where Polynesians became Māori. You can see the evolution and manufacturing of adzes for example."

Stevens says one of the significant jobs ahead for the committee is dealing with toxic waste left over from the smelting process, which is called spent cell lining, with up to 217,000 tonnes stored onsite.

Restoration in progress for area of great significance to Māori.

Close to sea level

"The spent cell lining. some of the most toxic stuff stored there, are being sent offshore for processing. It's chemically destroyed, and there are only a few places in the world, mostly in the northern hemisphere, that can do that."

"We don't pretend to have all of the answers. We don't pretend to have all the questions at this point. This signals our desire to have those things and be in the best position possible to restore the site."

One of the main concerns ahead for Ngāi Tahu is the impact of climate change.

"The peninsula is only about six or seven metres above sea level, and there's a lot we don't know about sea level rise and climate change. So, you know there are some really big questions there."