Marlborough's harbourmaster has been called up to help contain a fuel leak at Lyttelton Port.
A Marlborough District Council spokeswoman said Alex Van Wijngaarden was a specialist on oil spills and left for Lyttelton on Thursday.
It was not known when he would return. That was depend how long it took to contain the spill.
The leak happened on Wednesday when a Mobil jet fuel tank next to the Lyttelton terminal, containing 1.2 million litres of fuel, was severely damaged by a landslide after heavy rain.
Up to 1500 litres of fuel leaked into the harbour via stormwater drains before the leak was contained, and had formed a thin layer of fuel on the surface of the water before evaporating on Friday.
Mr Van Wijngaarden is a Maritime New Zealand national on-scene commander, and co-ordinated an oil spill operation for the Rena container ship that ran aground on the Astrolabe Reef off Tauranga in 2012.
A qualified sea captain, he was experienced in dealing with maritime incidents, his manager Hans Versteegh said at the time of the Rena operation.
Mr Versteegh and Mr Van Wijngaarden were not available for comment on Friday.
Mobil spokeswoman Krystal Guppy said about 85 per cent of the fuel that had spilled into a concrete-walled containment area around the damaged tank had been pumped into another tank on site.
It was not known how long the clean-up job would take to complete, but response teams had been working "around the clock".
"The rate at which we can pump out the remaining fuel will become slower as the layer of jet fuel within the containment area becomes thinner," she said.
- The Marlborough Express
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