The clean-up is finally beginning for a handful of New Zealand's most toxic sites, but there are thousands more in the queue behind them.

Photo: RNZ/Ian Telfer

The government set up a register for the thousands of former factories, sawmills and agricultural chemical dumps seven years ago but, since then, the subject has once again sunk from public view.

Has the clean-up effort been quietly placed on the backburner?

Joe Harawira looks like a healthy 70-year-old man who has taken good care of himself. He has had to.

In fact, one of his arms is paralysed and he feels constant pain throughout his body - having recovered slowly from near-total paralysis in the mid 1990s.

Photo: RNZ/Ian Telfer

"For six years, I had to learn to hold a knife and fork again, I had to walk all over again. I lost all my functions except my brain."

He is sure it all came from toxic chemical poisoning at the former Whakatane Mill, where he worked for 29 years.

He has battled for 33 years for recognition of the health effects of his exposure, and is now cheering for the Kopeopeo Canal - home to one of New Zealand's largest ever toxic clean-ups.

It is unlikely that project would be happening if he hadn't dedicated a large part of his life to having the mill's legacy recognised.

From Ngāti Awa's social and health centre, a modern and light building on the outskirts of Whakatane, Mr Harawira co-ordinates a group of former timber men called the Sawmill Workers Against Poisons.

He and thousands of other sawmill workers were "practically bathing" in the anti-sap stain chemical pentachlorophenol (PCP), unaware that it was heavily contaminated by dioxins, he said.

The government recognised the group in 2010, and offered them dedicated health services.

That was a big win, and so was the planned $10.2 million clean-up of the Kopeopeo Canal, Mr Harawira said.

Photo: RNZ / Ian Telfer

The canal itself is an ordinary, even enticing-looking waterway, which quietly drains the Rangitaiki Plains near Whakatane.

Ducks swim around, seemingly oblivious to the poison below.

Contaminated stormwater from the mill regularly washed into the canal for half a century until the operation closed in the 1980s, leaving the mud shot through with dioxins.

The World Health Organisation has declared dioxins - which can cause reproductive and developmental problems, damage the immune system, interfere with hormones and cause cancer - one of the most dangerous known chemicals.

Swimming in the canal is forbidden, and so is eating the eels that live in it: those plump kaimoana that were once a traditional food source for local Māori.

The Canal Remediation Project, led by the Bay of Plenty Regional Council, aims to clear and clean the now silted-up canal.

The plan, which changed in response to public concern, is to lift the 40,000m3 of contaminated mud, using a suction pump, dredge and hoses, from the canal onto paddocks that have been turned into contained treatment zones.

The team did a trial last year of an innovative clean-up method called bio-remediation, which will use fungi and bacteria to eat up the dioxins.

Photo: RNZ/Ian Telfer

Photo: RNZ/Ian Telfer

All that remains of that trial is two shipping containers, with the mud in fabric sausages at the bottom, planted out in poplar trees.

The project manager, Brendon Love, said the project would remove 70 to 80 percent of all the dioxins still in the district, though it could take 15 years.

If it works out, this will be a good news story - but there are no guarantees the method will work, and the costs are large.

One site among thousands

The Kopeopeo Canal is also just one of thousands of New Zealand sites contaminated by past industrial practices.

Past estimates by the Ministry for the Environment put the number of sites at approximately 8000, including about 1500 high risk sites. It said the cost for all clean-ups would be billions of dollars.

Against this, the government has set a budget of $2.6m a year for contaminated site clean-ups, though it has also funded one-off projects including the $22.5m clean-up of the Tui Mine in 2008.

Two years ago, the government began keeping a top 10 list of the most urgent clean-ups, called the Contaminated Sites Remediation Fund Priority List.

Insight has looked at the progress of the top 10, and found that the top four projects - the Prohibition and Alexander mines (#1 and #2), the Kopeopeo Canal (#3) and Port Nelson's Calwell Slipway (#4) - have received remediation funding, and are expected to begin within the next year.

The Department of Conservation said it would finally begin next month on the country's worst site: the historic Prohibition gold mine near Waiuta on the West Coast, which has arsenic minerals lying on its surface.

Photo: Suplied / DOC

Years of gold mining disturbed the naturally occurring arsenic and brought it to the surface, where it is now present at 5000 times the safe limit.

Two other projects on the list - the Rotowaro Carbonisation Works (#7), near Huntly, and the former Dunedin gasworks (#10) - are awaiting funding decisions, with the cost of the clean-ups not yet known.

Another site, on Bayly Road in Taranaki (#6), has since been found not to be contaminated.

Work on the other three sites - a contaminated groundwater aquifer in Auckland, and a stream and former gasworks in Wellington - has stalled or has no action planned, despite the sites being known about and studied for decades.

The Auckland Council and Greater Wellington Regional Council told Insight they believed the clean-ups would cost millions of dollars, and they felt there was little public pressure on them to act.

Clean-up deadline pushed back

Below the patchy progress on the government's own priority list, what of the thousands of others?

The Ministry for the Environment confirmed the date for regional councils to investigate high-risk sites was last year pushed out to 2020, and the deadline for cleaning them up was now 2030.

Photo: RNZ / Alexander Robertson

Its minister, Nick Smith, said the clean-up effort had not stalled - it was just not being hurried.

Contaminated sites were one of New Zealand's middle-level environmental challenges and not as much of a priority as climate change, clean freshwater or oceans management. Dr Smith said.

"The government's ambition is to be just consistently clocking our way through [the clean-ups], in a considered and sensible way."

Former Greenpeace toxics campaigner Gordon Jackman, however, said the national effort had stalled and gone under the radar.

Photo: RNZ/Ian Telfer

The Kopeopeo Canal clean-up was a good project but there were at least 36 other contaminated waste sites around Whakatane that were being ignored, he said.

Work on other timber mills, and the hundreds of toxic sites that appeared on lists held by regional councils, were mostly stuck and there was no real plan nor money to deal with them, he said.

"It's a very serious issue, and it's appalling that nothing's being done."

Mr Harawira said work had started on some of the other sites, in the form of a contaminated sites working group and a link-up with the Health Research Council to fund studies and remediation plans.

He wouldn't give up and wanted the government recognition he had fought so hard for turn into lasting good, he said.

As his own people, Ngāti Awa would say, he said, "if there's something wrong with the land, there's something wrong with us".

Are you living near a contaminated site? Email ian.telfer@radionz.co.nz

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