A truck which plunged into a central North Island stream this morning did not have any radioactive material on board, the Fire Service has confirmed.
The truck was discovered partially submerged in the Waihohonu Stream on SH1, on the Desert Road, just after 4am, but the driver has yet to be found.
The truck had signage indicating it contained radioactive material but the Fire Service has said there was no radioactive material in the truck at the time of the crash.
The truck and trailer unit was carrying more than 45 tonnes of general cargo as well as three 50kg containers of swimming pool cleaner and 12, 1200ml containers of another potentially harmful chemical, Fire Service assistant area commander Nigel Richards said.
"We believe the small containers are still on dry land however the three containers of swimming pool cleaner have fallen into the Waihohonu Stream, along with some of the other goods that were on board," he said.
"The three containers of pool cleaner appear to be intact and all the debris from the crash that has gone into the stream seems to have been stopped from going any further by the intake barrier at the Rangipo inlet."
Environment Waikato staff, contractors and police were at the scene.
The cab of the truck was badly damaged and lying in the water. The trailer remained on the bank.
Genesis Energy spokesman Richard Gordon said nearby intakes to the Rangipo station, at Poutu canal and from Moawhango dam, had been closed. Electricity generation at the power station had also been shut down, he said.
"That happened just after seven this morning. It has meant we are not producing any electricity out of a substantial power station at the moment.
"We've closed those structures to prevent hazardous material getting into the power station and the turbines. We will keep them closed until we have better idea of the situation.''
HAZARDOUS CARGO FEAR
There were 12 1200ml containers of the pesticide alpha-cypermethrin, which could be deadly to fish, insects and honeybees.
Alpha-cypermethrin is a pesticide used to kill ants, cockroaches and spiders, National Poisons Centre director Wayne Temple said.
If the substance entered the water then it was likely to dilute in the stream and cause few problems, but it could be toxic around the area where the truck entered the water.
While it was unlikely to kill cows or larger animals, there could be residue in a cow's milk if it drank contaminated water, Temple said.
"It could dilute very quickly and not cause much of a problem but if it's a low-flowing stream and not that big then it may cause some problems."
A person would have to ingest a large amount of the substance in order to be affected.
A Hazardous Materials Unit had been called in from Rotorua.
The Waihohonu stream flowed into the Tongariro river and eventually into Lake Taupo.
Police urged motorists to avoid SH1 in the Tongariro National Park, saying the Desert Road would be closed for some considerable time.
"Diversions have been put in place and motorists need to consider that these diversions will add time to their journeys.
"Police are working closely with the Fire Service at the scene. Safety to the personnel working at the scene, and to the wider public, is paramount,'' a spokeswoman said.
DOC Turangi area manager Dave Lumley said at this stage they had no concerns the hazardous substances would harm river life.
Police said the truck was straddling the railway line on State Highway 1 at the intersection with Selwyn Lake Rd.
A detour was in place and officers were directing traffic.
- STACEY KIRK, MIKE WATSON, CLIO FRANCIS and MICHELLE COOKE/Stuff
- © Fairfax NZ News
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