The Government will front up another $300,000 of taxpayer funds to address the operations of the aluminium smelter at Tiwai Point.
New Zealand Aluminium Smelters Ltd and the Environmental Defence Society today reached an agreement to remove 8000 tonnes of ouvea premix from the Southland town of Mataura over the next eight to 12 weeks.
The Government will pay half of the estimated million-dollar clean-up bill to remove the toxic waste.
But Cabinet has also approved $300,000 of Government funding to allow the Southland Regional Council to carry out site investigations of Tiwai Point.
Ouvea premix is a waste byproduct of aluminium production at Tiwai Point and releases deadly ammonia gas when wet.
Environment Court Judge Laurie Newhook's minute about the agreement specifically said it was a "standalone agreement to resolve the current situation and is not related to any agreement on the smelter's future or remediation of Tiwai Point".
The aluminium smelter will keep operating until the end of 2024 after Rio Tinto and Meridian Energy struck a deal last month.
Minister for the Environment David Parker said today's agreement between the smelter and the Environmental Defence Society gave him no confidence.
"To be honest I'm not particularly heartened by it," Parker said.
"We've yet to reach any agreement with the smelter as to their level of commitment to remediation of the site, if and when they leave.
"We've recently authorised again, through Cabinet, the advance of monies to Environment Southland so they can exercise their rights under the Resource Management Act to go on-site and do some site investigations because at the moment as minister for the environment I'm just about completely blind as to what is the level of residual contamination that will be left on the smelter site once it closes down.
"I don't think that's a very good state of affairs which is why again we are having to shell out taxpayers' money, this time to Environment Southland to go in and do some site investigations at the smelter."
In 2018, New Zealand Aluminium Smelters and Rio Tinto agreed with local councils and the government to remove the ouvea premix - a waste byproduct of aluminium production at Tiwai Point - over six years.
But flooding and fire at the site last year prompted the Environmental Defence Society to launch court action against the smelter's owners.
Parker said the taxpayer having to pick up half of the clean-up cost had somewhat soured the deal for him.
"I don't want to seem too churlish - it is good that the smelter has come to the party with half of that extra money and it is good that Inalco - the third party who processes it into a safe material - are also assisting. This is a good thing. But it leaves a slightly sour taste in the mouth that we are having to pay taxpayers' money," he said.
The million-dollar expedited clean up of Mataura came in addition to the $4 million committed in 2018 by the smelter, central government and local councils to clean up the waste from sites around Southland over six years.
Neither New Zealand Aluminium Smelters nor Rio Tinto agreed to an interview, but in a statement NZAS chief executive Stew Hamilton confirmed the waste would be transported from Mataura back to Tiwai Point.
"While NZAS does not own this material, we will remove it from the paper mill site and deliver a solution in the best interests of the community," the statement said.
"After discussion with the local and national governments, we will provide safe storage at NZAS to resolve this long-standing issue for our Southland community."