Maritime New Zealand will establish a dedicated unit to manage the response, investigation and inquiry into the Rena's grounding.
But officials are unsure how much the unit and its activities will cost.
The organisation placed an advertisement in The Dominion Post on Wednesday for a general manager for the unit that would comprise "MNZ staff, secondees and specialists".
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Oil responder Bruce Goff with the Terminator oil skimmer ready for deployment. on Sunday, October 23.
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Debris covered in oil have wash-up at Waihau Bay on the East Cape where Taika Waititi's Boy was filmed.
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EN MASSE: Protesters march against deep sea drilling in Tauranga, ahead of the appearance of the Rena's captain and navigator in court.
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IN NUMBERS: Protesters march against deep sea drilling in Tauranga.
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MAKING A STAND: Protesters gather outside the Tauranga District Court ahead of the appearances of the Rena's captain and navigator on Wednesday, October 19.
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AGAINST DRILLING: Protesters march against offshore drilling ahead of the appearances of the Rena's captain and navigator in the Tauranga District Court on Wednesday, October 19.
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Wellington Zoo vet Baukje Lenting with a Little Blue Penguin that is at Tauranga’s Bird Recovery Centre having oil cleaned from it using a toothbrush.
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PM John Key visits the Bird recovery Centre where he watches Little blue Penguins that have been cleaned of oil.
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Advice about wildlife that may be affected by the Rena oil spill, at Mt Maunganui.
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A seagull shows the effects of the spilt oil at Makatu.
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Containers on Mount Maunganui Beach.
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Volunteers clean up packets of burger patties from the broken container washed up on Mount Maunganui Beach.
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Prime Minister John Key attended a public meeting in Papamoa and went in a helicopter to see the Rena.
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ON THE MOVE: A container is hauled off the beach.
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A little blue penguin awaits transportation to the National Oiled Wildlife Recovery Centre in Tauranga.
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SCATTERED: Containers on the beach just south of Mount Maunganui.
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SALVAGE:Containers sit in the water on Mt Maunganui beach. Pictured Friday, October 14.
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STRANDED: One of the Rena's broken containers which washed up on Mt Maunganui beach. Pictured Friday, October 14.
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PULLED ASHORE: One of the Rena's broken containers which washed up on Mt Maunganui beach. Pictured Friday, October 14.
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Oil scooped from the surface of the water inside the Rena shipwreck's 1km exclusion zone.
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Oil booms are prepared at the Maketu Estuary in the Bay of Plenty, Thursday October 13.
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Territorial soldiers from Auckland clean up Papamoa Beach, near Tauranga, Thursday October 13.
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Containers washed up at Papamoa Beach, Thursday October 13.
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Two containers seen at Papamoa Beach on Thursday October 13.
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The clean-up operation on Papamoa Beach, Thursday October 13.
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Oil on Papamoa Beach, Thursday October 13.
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Packets of meat patties from a container off the Rena have washed up on Mt Maunganui beach.
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Police check a container that has washed up on Mt Maunganui beach.
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The bleak scene as containers wash up on Mt Maunganui beach.
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A man walks on Mt Maunganui Beach, with a container from the stricken Rena in the distance, Thursday October 13.
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A woman walks past a container from the stricken Rena, washed up on Mt Maunganui Beach, Thursday October 13.
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A container from the stricken Rena, washed up on Mt Maunganui Beach, Thursday October 13.
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Oil washes up on Papamoa Beach.
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WAITING COLLECTION: Scores of bags full of oil await collection in Papamoa.
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LOADING: Bags full of oil are collected from the beach at Papamoa.
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CLEAN-UP: Papamoa beach is covered with oil sludge
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SPOILED: Papamoa beach is covered in oil
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CRIPPLED: A wandering albatross covered in oil in Tauranga
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SOILED: Oil blobs at the Maketu shoreline
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CLEAN-UP: Volunteers collecting oil sludge from the beach at Papamoa
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CLEAN-UP: Volunteers help clean up the oil from the beach at Papamoa
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COVERED: A bird lies dead on Mt Maunganui beach today.
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Tauranga resident Chris Munro on Mt Maunganui beach, Wednesday morning.
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Environment Minister Nick Smith (centre) and Transport Minister Steven Joyce (right) at a public meeting in Tauranga to discuss the unfolding disaster.
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DEBRIS: Oil residues on Omanu beach at the 5 1/2 km beach entry point, Tuesday morning. Photographer Todd Murdoch says: 'I could smell the oil close to my house which is located 1km back from the beach.'
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CASUALTY: One of the penguins that died following the oil spill. This was found at Papamoa just after high tide today.
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UNSURVIVABLE: A bird that has been washed up on the beach, coated in oil.
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LONG JOB: Volunteers help clean up the oil from the beach at Mt Maunganui.
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Oil on the beach near Mount Maunganui.
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Sunny, 9 years, with his dead fish on Mt Maunganui beach.
About 350 of the 1700 tonnes of oil on board spilled into the ocean after the cargo ship ran aground on the Astrolabe Reef, near Tauranga, on October 5.
Several inquiries are under way and the ship's master and navigational officer have been charged under the Maritime Safety Act and are awaiting trial.
A Maritime NZ spokeswoman said the Rena response was expected to take up to two years – and a dedicated unit was needed so the organisation could also handle other business-as-usual activities.
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Salvage crews continue to slowly remove containers from the Rena.
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Food products are tipped out of a container at the Truman Lane container processing site.
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Stevedore Tix Rirnui wraps butter removed from Rena. The butter is being sent for testing to see if it can be converted into bio-diesel.
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The crack in the Rena's side.
"MNZ is a small organisation, and large numbers of its staff are already working on these work streams. Given the long-term nature of the Rena response, this will impact on MNZ's ability to deliver its mandatory regulatory and safety functions."
The unit's core duties would be to provide and co-ordinate the investigations, prosecutions, salvage operations and removal of the wreck, as well as assisting with negotiations between the Rena's owners and insurers.
Many Maritime NZ staff were now working on the Rena incident, but despite this, the size of the business unit and its budget could not be provided, she said.
Transport, Accident and Investigation Commission spokesman Peter Northcote said while most of the fact-gathering had been done, its investigation into the grounding was at an early stage.
A time frame of between 12 and 24 months from the accident date was common, but the commission aimed to finish the investigation in a year, he said.
Salvage crews have removed 166 of almost 1300 containers on the Rena.