The pungent odour of millions of litres of curdling buttermilk has Eltham residents fuming.
For about a month, Fonterra dumped the milk byproduct at the Eltham wastewater treatment plant as it dealt with spring's record milk production.
It was supposed to be an ''environmentally friendly'' solution in a deal struck with the South Taranaki District Council.
But those living near the plant say it has been an intermittent assault on their nostrils as the buttermilk begins to break down.
Castle St resident Maureen Drylie, who lives opposite the plant, said they were promised the odour wouldn't be noticeable.
But for the last three weeks the smell was inescapable.
"They have to vent it you see,'' she said.
''Now, who would imagine that if you put sour milk somewhere it's not going to rot and make a smell."
Mrs Drylie said she had spent one particularly bad night sleeping with perfume under her nose.
''I would have quite happily shipped off to a motel if it hadn't of been so late.''
Mrs Drylie said the vile smell had also created a rather significant blowfly problem.
She said while she accepted the district council had been working hard to solve the issue, Fonterra should never be allowed to use the facility again.
Nearby resident Sheree Renshaw just wants the ''constantly foul'' odour gone.
''Some days it's the smell of dead beast, others it's the smell of Rotorua but worse,'' she said.
''On a still night we can smell it in the house.''
She said she was now concerned about her children's health as they had been experiencing sore throats.
''I don't want to jump to conclusions but there is such a stench that you wonder how much is in the air.''
Fonterra director of operations Robert Spurway told the Taranaki Daily News as far as they were aware smell should not have been an issue.
''Firstly, we absolutely apologise to all local residents who have suffered any inconvenience as a result of this,'' he said.
''We worked with the council before we sent any byproducts for disposal at the ponds.
''And we understood that the ponds had been designed specifically for the disposal of the type of waste we sent there.''
He said they were now focussed on resolving the issue.
''We were advised that they had an odour problem back in October and we immediately stopped sending any further product to the ponds.''
STDC chief executive Craig Stevenson said the council was now treating the wastewater using a specially cultured mix of bacteria produced on site.
''We're certainly not happy that there is an odour which is inconveniencing some of our residents and with the benefit of hindsight - it needed more time and preparation - but we didn't have the luxury of time,'' he said.
''We were trying to do the right thing by agreeing to help Fonterra by providing an environmentally acceptable solution for an exceptional circumstance.''
He said it could take weeks to resolve but council engineers were working ''their butts off''' to minimise the impact.
Mr Stevenson said three million litres had been put in their Eader facility which was designed to capture gases created during the waste treatment process.
''On top of this we added another one and a half million litres of wastewater to dilute the buttermilk and help aid the treatment process.''
Mr Stevenson said once broken down the treated liquid would be pumped along with the town's treated wastewater to undergo further treatment at the Hawera plant.
An odour suppression system had also been installed.
So far it had cost the council about $60,000 mitigating the odour, a cost the council will be speaking to Fonterra about, he said.
Taranaki Regional Council director of resource management Fred McLay said they had received a number of complaints about the odour.
''As a result of one of these complaints, an abatement notice has been issued to the South Taranaki District Council, which manages the facility,'' he said.
''If legal obligations are not met, relating to offensive odours beyond the site boundary, then this council will consider further enforcement action.''
■ The South Taranaki District Council is holding a public meeting on Monday to explain what's being done to speed up the treatment process and the measures taking to mitigate the odour. Held at the town's Municipal Chambers, the meeting starts at 7pm.
- Taranaki Daily News
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