Emergency services respond to the incident at South End School on Friday. PHOTO/JADE CVETKOV

PAM GRAHAM

pam.graham@age.co.nz

Police will be back at South End School in Carterton today trying to find the source of the mystery vapour that triggered one of biggest emergency chemical responses ever in the Wellington region.

On Friday, 107 people at the school went through a decontamination process after several became sick enough for hospital checks.

Parents were welcome to attend the 9am assembly today but have been told any questions they have about what happened on Friday will be addressed after the assembly.

Wairarapa Area Commander Inspector Scott Miller said there was nothing to suggest this was a deliberate attack to target the school or the children, and no one had been sick since.

“It is vapour, it is very strong, and it has been here for a short period of time. It’s blown away in the wind,” he said.

Ministry of Health officials were back at the school on Sunday, but it was cleared to reopen on Monday.

The Army went to the school on Friday night with the idea that they would be needed to take soil samples.

But no physical objects or any residue had been found, which negated the need for soil samples.

Both children and residents reported a smell of sulphur or rotten eggs.

The residents on the other side of the road reported the smell was the strongest there, with a south easterly wind blowing it across the school.

Police are not ruling anything out until the investigation has found the source of the smell but said the nearby bacon factory was in the wrong direction.

The Civil Aviation Authority had helped police identify and track planes and pilots, after initial reports from one pupil that something had fallen from a plane.

There were eight aircraft in the area between 1pm and 3pm on Friday, including a Tiger Moth, helicopter, topdressers and a Cessna.

The Cessna was flying from Hawke’s Bay and was over the school at 2.15pm but it was a passenger aircraft, with two people on board.

“You never rule out anything until the end of the investigation,” he said. But the Cessna was very unlikely to be the source.

Police had also talked to local transport companies, to identify what might be carried that smelt as described.

Police were talking to the clandestine [meth] lab team in Wellington and also to Institute of Environmental Science and Research scientists about where the smell could have been from.

But he stressed, “we are advised the smell that is described is not one you would get in drug manufacturer,” he said.

Miller said the police officers would be at the school to reassure teachers and children, and they would be there all day.

Police would “sit down and speak to the children and listen to what they have to say and see if we can get some more information”

“But it is more around that they feel safe at school.”

The emergency services will also be holding debriefs this week.

Carterton mayor John Booth said on Sunday that there was a lot of conjecture and people needed to let authorities do their job.