A salvage crew is expecting to resume pumping oil from the Rena today, after small platforms were attached to the side of the container vessel grounded off the Tauranga coast.
The crew, operating from the platforms and using an Archimedes pump, will work first on the rear port side tank and hope to move 770 tonnes - the bulk of the heavy fuel oil still on the ship - to the waiting barge Awanuia.
"If the weather stays fine, we will start transferring the oil. How long it takes, I don't know," Maritime New Zealand (MNZ) salvage unit manager Bruce Anderson said.
"We have to take it slowly and make sure things are set up properly."
The fuel was cold, and dense like Marmite, and had to be sucked from the tank, he said.
So far, 350 tonnes of the 1700 tonnes on board had escaped, polluting Western Bay beaches.
Mr Anderson said another 220 tonnes was in two settling tanks near the engine room, and the rear starboard tank holding 350 tonnes was underwater.
Yesterday, MNZ acknowledged it should have acted more quickly in organising volunteers to help with the clean-up.
MNZ director Catherine Taylor told a media briefing about 2000 people had volunteered to help clean up.
"In any situation like this, there are things that you learn from it and organising the volunteers was something which we have come to a bit later than we probably should have," she said.
MNZ was waiting to confirm reports the oil had reached Whale Island, considered to be a sanctuary for native flora and fauna, 9.6km from Whakatane.
Ms Taylor thanked the hundreds of volunteers helping with the clean-up effort.
However, she urged more people to volunteer.
The oil washing up on beaches was so toxic one young woman helping with the clean-up had used her cellphone and wiped the numbers off the faceplate, Ms Taylor said.
It was vital oil from the beaches did not spread to "clean" areas.
"At Papamoa Beach, in the car park, you could see large globules of oil that had come off the beach," she said.
"We don't want that contamination, because what that means is that the oil will then go back into the system, through the stormwater drains, out to sea and be recirculated."
People needed to wear protective gear and make sure their shoes were covered so they could discard the covering as they left the beach.
"It's a very serious issue. It's very toxic."
