The figure of $80m reported earlier in this story has been amended to $80,000.
The Paritūtū site in the late 1960s shows the location of Bore 42 (red dot) and location of the two waste ponds across road. By the late 1960s a stormwater pipe had been installed. Photo: Supplied
Leaked documents indicate testing for contamination at the site of a controversial chemical plant in New Plymouth might need to be extended beyond its boundaries.
Ivon Watkins (later Ivon Watkins-Dow) made the herbicide 2,4, 5-T at Paritūtū from the 1960s through to 1987.
The herbicide was a key component of Agent Orange - the defoliant used by the US military in the Vietnam War - which has been linked to cancers and birth defects.
The plant was demolished last year and Dow and its New Zealand-based remediation partner Tonkin & Taylor are part way through a clean-up process expected to take several years.
Tonkin & Taylor has finished a preliminary site investigation which has been submitted to the Taranaki Regional Council, which has asked consultants Beca Group to independently reviewed it.
Documents obtained by dioxins researcher Andrew Gibbs raise questions about whether the site investigation should have been extended beyond the former plant's boundaries to where offsite liquid waste ponds once were at the base of Paritūtū.
A map from the leaked report. Photo: Supplied
The documents - part of an Environmental Assessment Project the Taranaki Regional Council requested of Dow in the 1990s - include a 1994 hydrology survey report (which cost $US80,000), a 2020 ground water management report, and a summary of a lost 1996 contamination report.
Photo: Taranaki Herald
TRC is unable to say what happened to the full version of the 1996 contamination report.
The official Dow media statement for the 1996 report pointed to two areas of low-level phenoxy and chlorophenol contamination on the 16-hectare site, but did not reveal where they were.
"They are present at two locations on the site in quantities of less than 15 parts per million. This compares with the United States Environmental Protection Agency guidelines - reviewed for New Zealand marine environment conditions - of 30 parts per million," the media release said.
It emphasised that the contaminants were not a risk to nearby residents and would not reach the coastline which was now a marine park.
The media release said a summary of 1996 EAP report was available to reporters only on request and for an unspecified payment.
The summary was one of the documents obtained by Gibbs.
Maps labelled "confidential" in the summary when matched with bore testing results in a 2020 ground water management report, also obtained by Gibbs, indicate testing bores 39 and 42 were the areas of concern.
Gibbs said this was significant.
"One [bore 39] was the old dangerous goods area out on the western boundary where drums [of chemicals] were stored.
"It was to be capped over [covered in asphalt] but they never really explained where the other one (bore 42) was.
"So, the big big reveal here with the leak of this information is that there were unexpectedly high levels of contamination found between the office block and Paritūtū at bore 42, and what it looks like to me is that the residue from the waste ponds has migrated back into the bore hole."
Gibbs said the bore 42 result was interesting because it was not close to other possible sources of contamination such as the manufacturing plant.
"It pretty much confirmed what residents have been saying for the last quarter century that there was a substantial discharge of liquid waste under Centennial Drive into ponds and then down the access way to Back Beach."
This could place contamination outside the boundary of the plant.
Maurice Bevan lived on Scott Street a few hundred metres from the Paritūtū plant in the 1960s.
He has previously shared his experience of seeing chemicals seeping through the cliff face at Back Beach and showering under a stormwater pipe connected to the plant to warm up after surfing.
He said the documents appeared to confirm what residents had long thought.
"I don't think some people have taken it seriously. There was ponding and it wasn't just stormwater coming from the plant; it was actually the chemicals coming from there.
"There was like two ponds together and then it's made its way - because it's all ironsand - it's made its way through and down onto the beach."
Gibbs said another takeaway from the leaked documents was the sheer cost of the 1994 hydrology investigation.
"That's a heck of a lot of money to spend. There must've been very good reason."
The costs are laid out in the introduction to the hydrology report obtained by Gibbs.
He said it was also remarkable a key part of the Environmental Assessment Project - the full 1996 contamination report - had been lost.
"The TRC can't find the full contamination report which has all the soil tests and that should really be on the table in the current investigation. This historical information is really key."
Dow response
Photo: Taranaki Herald
US multi-national Dow said as part of the ongoing investigation of the entire Paritūtū site a large volume of documents had been reviewed that were being thoroughly examined as part of the Preliminary Site Investigation (PSI).
"Currently, the draft PSI is under review by the Taranaki Regional Council and its independent external expert.
"In line with our agreed process, we are not in a position to comment on individual documents at this stage.
"Should the expert review identify any documents requiring further clarification, these will be addressed in the next phase of the project."
Dow did not respond to questions about whether it had a copy of the missing EAP 1996 contamination report or on the cost of the investigation.
Tonkin & Taylor
Dow's Taranaki remediation partners Tonkin & Taylor reinforced the US chemical giant's position.
It said its ongoing site investigation followed a structured path agreed with the key stakeholders and was in line with the New Zealand Contaminated Land Guidelines.
"The documents you have referenced are among the very large number examined as part of the Preliminary Site Investigation. The draft PSI report is currently under review by the Taranaki Regional Council and its independent external expert.
"Therefore, at this stage in the agreed process, it would not be appropriate to provide commentary on individual documents seen out of context."
Tonkin & Taylor reiterated that if the expert review identified any documents which might warrant further clarification, that would be included in the next phase of the investigation.
In May 2000, under instruction from the Taranaki Regional Council, Tonkin & Taylor took soil samples and tested for phenoxy herbicides in the area of an open drain / gully that formerly led downstream from the ponds to the beach, but no mention was made of contamination at or near bore 42 identified in the 1996 contamination report.
Tonkin & Taylor's 2000 report found no contamination and recommended to the TRC that no further action was required.
Taranaki Regional Council position
TRC director environment quality Abby Matthews confirmed the full 1996 report was missing.
"Unfortunately, we have been unable to locate DowElanco's full 1996 EAP report in our archives."
No explanation was offered as to where it might be or how it came to be lost.
Matthews said the TRC had engaged Beca to review investigations undertaken by Tonkin & Taylor in relation to the Paritūtū site.
"We intend to let that review go through its due process. We are happy to pass on any relevant information to Dow, and to the consultant for consideration during their review process, but we will not be undertaking separate investigations or forming any views at this early stage."
New Plymouth District Council
Photo: Taranaki Herald
The New Plymouth District Council didn't directly respond to questions about the waste ponds or the open drain.
Instead it referred to a pipe it installed at the end of 1966 saying "it had been historically used for discharging cooling water and stormwater".
Media reports and letters between officials at the time indicated concerns about the discharge from the chemical plant.
A newspaper article prior to the pipe being installed described a "black, grass-destroying waste outlet from the Ivon Watkins Dow factory snaking its way through the crunchy grass of Paritūtū Centennial Park before tumbling down a minor fall, covered in rotted vegetation".
While an editorial in the Taranaki Herald in October 1963 noted that: "starting close to the (Centennial) Park's Paritūtū Crescent boundary, there is a large smelly, unguarded pool of considerable danger to children playing in the park, the flow has destroyed the old pathway to the beach (which the public are still directed by signs to use)."
A letter from the District Inspector of Fisheries to the Secretary for Marine in November 1966 referred to the source of the discharge.
"The effluent is piped from the factory under a public road and then runs in an open drain 50 yards then over a steep cliff onto the beach below. The smell is overpowering and the grass by the drain is dead."
In another letter, acting secretary for marine C W Franks wrote to the City Engineer in July 1967: "It's now been reported that this stormwater is discharging into a stilling basin at the top of the beach, and that there is considerable poisoning of bird life in the area. This is a very serious matter and the possibility of serious injury to some child cannot be overlooked."
Also in 1967, marine works engineer R A Simpson wrote that no practical steps had been taken to stop chemical spills on to the beach.
"We suggest the company should agree to inspect daily every morning for spillage of chemicals, and in the event of such an accident hose the beach until all traces disappear and must post a man until all danger is past."
NPDC said an independent consultant (Tonkin & Taylor) was currently reviewing the Paritūtū site investigation and it would wait on the review's results before commenting further.
That wasn't good enough for former resident, Maurice Bevan, who is living with stage 4 cancer.
"At the end of the day for the people of Paritūtū there's been no consideration for them at all from the government, the council the whole lot. They just turn a blind-eye and don't want to know about it.
"We were thrown under the bus with these chemicals all that time. What a hell of a stench. Horrible. And how many of us are left, you know, originals left. I'm guessing it's myself and two or three others that I know of and we're just telling the truth."