Fate dealt eruption victim unlucky hand

Friday's eruption on Raoul Island could have taken the lives of any one of the six Department of Conservation workers.

It was only by chance that it happened to be Mark Kearney inside the crater when the eruption occurred, said DoC's Warkworth area manager Rolien Elliot.

The job of taking temperatures inside the crater was rotated among the workers on a voluntary basis each day.

"Taking the temperatures inside the lake is needed as an assessment of volcanic activity," Ms Elliot told the Herald.

"It is the first indicator of what may happen here on the mainland - it is done on contract for GNS [Geological and Nuclear Sciences]."

Ms Elliot said on the morning it was decided that Mr Kearney would make the one-hour trek to the crater, while four other DoC workers set off to do weed control work.

The sixth DoC worker, Melanie Nelson, stayed back at the hostel to do MetService work and to fulfil standard operational safety procedures.

Taking temperatures inside the crater lake was something all six members had done, but it was "something that Mark liked to do".

When the blast came at 8.30am, it would have coincided with Mr Kearney being at the bottom of the crater. He had left base at 7.30am to make the journey to the lake.

A small earthquake was recorded 10 minutes before the eruption, but such events were standard on the island and it was likely that Mr Kearney would not have been alarmed by it.

When the blast came, Ms Nelson immediately radioed Ms Elliot in New Zealand to report it.

She also called the weed control team to check on their whereabouts and safety, but failed to make contact with Mr Kearney.

"They [the weed control team] were on the southeast side of the island, on the edge of the crater rim," Ms Elliot said.

It took 25 minutes for the foursome - Jim Livingstone, Morgan Cox, Evan Ward, and Lynda McGrory-Ward - to arrive back at base.

The survivors waited for two hours for activity to die down, before Mr Livingstone and Mr Cox were cleared to scout the crater's edge for any sign of Mr Kearney.

"They proceeded along the rim and took a look down into the crater. They spent 30 to 40 minutes walking along the track, but only found complete devastation," Ms Elliot said.

"Trees had been uprooted, boulders were everywhere, and there was ash, mud and steam everywhere. They could not go down as there was black stuff, water, and steam and more earthquakes happening."

The survivors were evacuated at 6pm, although many personal belongings had been left behind.

All five DoC workers are returning to the island and will arrive by boat by 9am today.

An Air Force Orion P3K aircraft is to fly to Raoul this morning to help assess whether the island is safe for people to land.

GNS volcanologists aboard the flight will carry out a visual check of any volcanic activity from the air to complement an assessment by boat-based scientists.

A 40-minute helicopter search on Friday failed to spot Mr Kearney, who was last seen carrying an orange pack.