A large dumpsite has been uncovered by volunteers working to restore a Taranaki pa site.
About half a hectare of syringes, bottles, hospital and electrical equipment, and potentially asbestos-riddled trash has been uncovered at Hawera's Turuturu Mokai reserve.
The find, thought to date back to the 1960s, has prompted a Taranaki Regional Council investigation.
The site is metres from the Tawhiti Stream, a water source for both Fonterra Whareroa and Silver Fern Farms.
Regional council compliance manager Bruce Pope said the council was investigating to determine if there were any environmental effects. He would not comment further while the investigation was ongoing.
Milton Whareaitu, an affiliate of Ngati Tupaia and Ngati Ruanui, began working at the reserve as a voluntary project manager 18 months ago, clearing rubbish, debris and overgrowth.
He found the dump site recently when he noticed glistening objects lifting to the surface of the ground.
A digger brought in to investigate further uncovered what could be tonnes of waste thought to be more than 50 years old.
Mr Whareaitu's biggest concern was who would be responsible for cleaning up the mess and ensuring the waterways surrounding the area stayed clear of potential contaminants.
"We need to remove it and put it in its rightful place," he said.
"Then there's the expense of that, that's of equal concern."
The work Mr Whareaitu and others have done onsite has been voluntary. All tools and materials have been donated, and there is no budget for a site cleanup.
Silver Fern Farms plant manager Ash McKay said the company had looked into the water issue and had no concerns at this stage.
"Our site takes water from the Tawhiti Stream for non-potable use only, mainly washing down cattle," he said.
"The water upstream of the plant is tested six times a year by the Taranaki Regional Council and we are confident that it is suitable for non-potable use.
"Our potable supply is from an alternative source provided by the South Taranaki District Council."
Fonterra Whareroa Taranaki and Manawatu general manager Scott Walls said the situation had been assessed by the site's environmental manager.
"We are 100 per cent confident in the quality of the water at the Whareroa site," he said.
"We test against the New Zealand drinking water standards, so we fully comply with that and we haven't had any issues that I'm aware of."
A cleanup campaign was started at the pa after Mr Whareaitu visited the site in 2012.
A former public reserve, it was said to be one of the oldest fortifications erected by Maori and was fought over during the Taranaki Land Wars of the 1860s.
It was once a popular public playground.
The redoubt is now under the control of Ngati Tupaia.
Mr Whareaitu said he was grateful to know that neither site would be affected by the find at this stage but he was still concerned with the best way to clean up the mess.
- Taranaki Daily News
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