A "sickening" smell from the controversial new private landfill at Coal Creek is being investigated by West Coast Regional Council after numerous complaints in the past week.
One Taylorville resident said they initially thought the smell could be a chemical leak from the Grey District Council's Greymouth water treatment plant across the road.
However, the regional council confirmed on Monday the smell was thought to be linked to drainage water collected in sumps in cells at the Taylorville Resource Park landfill.
"We're investigating and we certainly have smells. It's the water that's the issue," consents and compliance acting manager Rachel Clark said.
The site was able to operate in the meantime but the council had taken water samples and was awaiting lab results before further action.
"They can't cease [operations] as such. What they initially did was put a cover on the sump, thinking it might alleviate the issue. It turns out it didn't."
Council staff believed the odour might be contaminants in the water.
Clark said persistent complaints the site was receiving waste from the clean-up of the former Bromley wastewater treatment plant in eastern Christchurch were not true.
"They are all wild rumours."
The Greymouth Star understands the waste from Bromley was put into sealed containers and disposed of at the Kate Valley landfill in North Canterbury.
Clark said the council had asked Taylorville Resource Park owners for a detailed inventory of what material was being disposed of at the site.
They did have a variation to dispose of tomato vine material from a commercial grower in Karamea, which the odour might be linked to.
"Initially, as far as I'm aware, it's material from Karamea."
Further action would depend on the water sample results in the coming week.
"We'll take our next steps based on that."
A Taylorville resident who contacted the Greymouth Star on Thursday said the smell had been extreme in the past 10 days.
The smell would "bring up your morning tea" and it had been a talking point in the neighbourhood.
They initially noticed it while driving from Taylorville to Greymouth, but the foul odour had also wafted up and down the Grey River valley depending on the 'Barber' katabatic wind and the time of day.
"It gets sucked into the car and it's just the most revolting stench you could ever smell," the woman said.
She and her husband were now avoiding driving the direct Taylorville Road route to Greymouth, instead going the long way around via Stillwater, "because the smell is just so sickening".
The district council said on Monday it had not fielded complaints directly about the smell but it remained concerned about the site.
Greymouth Mayor Tania Gibson said she had detected "no smell whatsoever" during a recent visit to the landfill.
"It was a very clean site, tidy."
However, she was awaiting with interest the findings of a report her council had commissioned on the circumstances around the way the site had been consented by the regional council.
Group manager operations Aaron Haymes said they had not fielded smell complaints as such but the council remained concerned.
"It's interesting because the type of material they're allowed to dump in there shouldn't be giving off offensive smells."
However, the council was aware of two consent variations for the site to take other material, including tomato vine material.
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