Almost 10,000 tonnes of ouvea premix, a by-product from Tiwai Point smelter, was dumped at the site in 2014 by Taha, which was under contract to New Zealand Aluminium Smelter to provide a zero-waste solution for the substance.
A ‘‘handshake deal’’ was made with concerned parties last week, but Gore Mayor Tracy Hicks said yesterday the Rio Tinto board turned it down.
‘‘It’s fair to say everybody is feeling pretty sick.
‘‘I’m annoyed at how this has played out and the performance of Rio Tinto over this period.’’
When wet, the substance is capable of generating ammonia gas, which could be harmful to human health or the environment.
Floods in the region last week sparked fears the chemicals could become saturated and hazardous.
Gore District Council chief executive Stephen Parry yesterday announced the deal he had struck with New Zealand Aluminium Smelters chief executive Stewart Hamilton had been turned down by Rio Tinto.
He said it would have resulted in the dross being removed from Mataura by the end of June and sent to a building at the Tiwai Point complex for storage.
‘‘It’s my understanding from conversations with Stewart that Rio Tinto’s rationale for refusing to take the dross was that it didn’t want any more liabilities on the Tiwai site before the company’s strategic review is completed at the end of March.’’
Mr Parry said the original deal struck with all Southland councils, landowners and NZAS to move the dross stored throughout Southland was still in place, but could not speed up the process.
‘‘It would be ideal if Stewart Hamilton could attend the meeting in Mataura ... to explain to our residents in more detail why his company can’t take the dross.’’
The public meeting was to be held at the former town hall in River St, Mataura, at 7pm tomorrow.
He said the deal announcement was agreed to by the three parties involved in the discussion — the Gore District Council, NZAS and a Ministry for the Environment senior official.
‘‘The negotiations concluded on the understanding that a high level agreement had been reached,’’ Mr Parry said.
The Sort The Dross campaign had been protesting the storage of the substance, and spokeswoman Laurel Turnbull said the group was angry with the situation.
‘‘They did tell us when it got put in there if Mataura flooded, and fumes got bad, the whole of Mataura would have to be evacuated ... people did smell the fumes.’’
Mr Hamilton said NZAS had ‘‘fully co-operated with GDC regarding the council’s long-standing plans to remove the material that is stored at the Mataura Paper Mill.
‘‘We remain committed to a solution that removes the material. NZAS has committed to contributing $1.75million to the costs of safely removing and processing the material.”
A $4million package to remove the substance was brokered by the NZAS, the Government and Southland councils in 2018, and a contract with Australian company Inalco Processing Ltd would have 22,000 tonnes of it removed in six years but was delayed.
A press release from GDC said when the council became aware it was at the mill, it was advised to allow Taha to apply for a resource consent retrospectively, which was approved in October 2015 for two years and included several conditions.
Those included a $2.3million bond; this was appealed and nothing was paid to the council. Taha then went into liquidation.
Mr Parry said the consent was issued as a tool to ‘‘ensure the dross was managed as safely as possible and with the least risk to our residents in Mataura’’.
‘‘It was not as if the council had a choice — the dross was already in the old paper mill’s building.’’
