The Prime Minister is demanding answers as to how the Rena container ship hit Astrolabe Reef and started spewing oil into the sea.



John Key was visibly riled by the situation when he spoke to reporters in Tauranga today.



He said the Rena had "ploughed into" the well-known Astrolabe Reef at 17 knots in calm conditions on Wednesday "for no particular reason".



Key said there were "serious questions to be answered" and two inquiries had been launched.



He said it was a "major ship" owned by a "significant international shipping company".



"We want to know why."



Key rejected criticism that the salvage and oil-recovery effort had been too slow saying he had flown over the ship and he could see it was a "very, very complex situation".



"I can give (locals) assurances that everyone is doing everything as fast as they can.''



Asked if the presence of international visitors and media for the Rugby World Cup meant it was a bad time for the accident to happen he said it would always have attracted media attention as it was such an unusual event internationally.



Key is due to fly to Christchurch this afternoon to watch the All Blacks quarter-final with crowds in Hagley Park.



Opposition parties, the Greens and Labour, have both claimed oil booms should be put down now to prevent toxic oil from reaching sensitive Bay of Plenty estuaries and wetlands.



And Labour are blasting the government for being '' woefully under-prepared.''



Green MP and marine spokesman Gareth Hughes says the government could ''lessen the risk'' of the deadly substance reaching vulnerable wildlife.



''It is going to be much easier to keep oil out of wetland mudflats than to have to clean it out afterwards,'' he said of a potential ''catastrophic spill'' from the container ship.



Maritime New Zealand is investigating using booms at Matakana Island and Maketu Estuary but there is no certainty, he said. It's also not clear if this will include Little Waihi Harbour.



''Both the Maketu and Little Waihi harbours are important recovering wetlands and should therefore be provided with oil boom protection immediately,'' he said.



''The urgency is real: Metservice now have a strong wind advisory in place for the Bay of Plenty with winds turning Northeasterly and gusting up to 40 knots on Monday.''



BARGE ARRIVES



The Awanuia, a a double hulled bunker barge capable of holding 3000 tonnes of oil, reached Rena this morning and officials say it will be a "matter of hours" before it can start receiving Rena's load.



Officials are desperate to get the oil off the ship which ran aground on Astrolabe Reef on Wednesday, leaking about 10 tonnes of oil into the sea.



Though naval architects say the ship is currently stable, forecast bad weather moving in tomorrow could change that and hamper efforts to avert a massive environmental contamination.



The oil that has already leaked into the sea is being sprayed with dispersant and today two vessels are undertaking on-water oil recovery.



Health authorities have issued a warning that Bay of Plenty people should not eat seafood from water with visible oil contamination.



Medical Officer of Health Jim Miller said any seafood that had "off or petrol like odours" should be avoided.



He particularly cautioned against eating shellfish from Motiti Island which is the nearest land to the Rena.



Despite an apparent slowing of the oil spill, preparations are still being made for a larger event if the ship breaks up and sinks.



Shore assessments are being carried out in areas where oil could come ashore and the New Zealand Defence Force has personnel on standby should a clean-up be required.



WAKE-UP CALL



The Greens have called for a moratorium on all off-shore oil exploration as the grounding of the cargo ship Rena raises serious questions about the country's ability to deal with major oil spills.



It comes as Key last night sounded an ominous warning of a potential environmental disaster.



"It's going to be a huge [salvage] exercise and the prime minister believes we need to brace ourselves for a very significant event," a spokeswoman for Key told the Sunday Star-Times.



Environment Minister Nick Smith said the Rena "had the potential to be New Zealand's most significant maritime pollution disaster in decades".



Salvage crews are in a race against time to remove oil from the stricken ship and prevent further spills, as big swells and gale force winds are predicted for tomorrow.



Gareth Hughes, the Green Party's marine issues spokesman, said the accident should serve as a wake-up call for the government. "They need to put a moratorium on all drilling, including test wells, because what we're seeing is that Maritime New Zealand is stretched dealing with what would be considered a minor spill compared with what you saw in the Gulf of Mexico," he said, referring the BP disaster last year.



Key said the government was introducing legislation to ensure adequate environmental protections were in place if deep-sea drilling was undertaken.



"The prime minister would point out that there is no connection between deep sea drilling and a maritime accident of this nature. They are completely unrelated except that they both occur at sea," the spokeswoman said.



Resources were yesterday being sent from Australia, and four navy ships and 500 Defence Force personnel were put on standby, as salvage crews tried desperately to seal the ship's fuel tanks. Officials estimated that Rena has spilled about 20 tonnes of oil.



Hughes said New Zealand was not geared to cope with the potential disaster.



"We've had to wait days for international experts to arrive in New Zealand, we've had to wait days for equipment to come from Australia.



It highlights that a small country with little oil infrastructure faces considerable risks when we have oil leaking into our environment. This has to be a wake-up call for the government in regards to its deep-sea oil plans and energy strategy."



Labour leader Phil Goff said it was not possible to stop all oil exploration, "but we are going to make it conditional on every environmental safeguard being put in place to stop any disaster occurring. We cannot afford a disaster like the Gulf of Mexico".



The spokeswoman for Key said: "This is a very complex and very difficult operation and the reality is the salvage operation will take weeks, not days. New Zealand has one of the best salvage teams in the world on the job - they are the experts and it's important that they are allowed to do their work."



Key is to meet today with local officials and the accident will be discussed at tomorrow's cabinet meeting.



The Star-Times spoke to a Tauranga resident, Tommy Kapai, who sailed his yacht within metres of the Rena yesterday. He said he could "taste" the oil from the grounded vessel. He said it looked like a ghost ship. "There is no life on it, it looks like an old, tired granny of the sea.



"You can see the red of the bottom of the boat and then as you come closer you start smelling the oil and then you can actually taste it in your mouth. It's gross."



He saw a dead penguin coated in oil floating past.



The Rena is carrying about 1700 tonnes of oil - making a spill a potentially bigger environmental disaster than the 2009 Queensland one, when 230 tonnes of fuel spilled into the Coral Sea, north of Moreton Bay. That cleanup took 16 months and cost $5 million.



Salvage expert Jon Walker, flown in from Singapore, said the company hoped the first pumps could be activated this afternoon but he admitted that the weather was a factor for the success of the mission.



Strengthening nor-easters and increased swell are forecast for tomorrow ahead of a storm on Tuesday.



Maritime pollution response co-ordinator Mick Courtnell said capacity was being marshalled to deal with the worst case scenario - the ship sinking and all the oil being released.



If the ship sinks, another danger arises as some of the containers contain the alloy ferrosilicone which, if it contacts water, gives off hydrogen - which is a fire risk.



Walker said salvaging the ship would require removing the containers off the ship. As the Rena does not have cranes, another ship with a crane would have to be parked alongside to attempt the delicate task.



The ship could then be pulled by tugs off the reef.

-Fairfax NZ