Salvage experts, some from the same team that rescued the Pasha Bulker off Newcastle in 2007, spent yesterday frantically trying to assess and contain the damage to the 230-metre, Chinese-registered Shen Neng 1, stranded on a coral shoal 70 kilometres east of Great Keppel Island off the central Queensland coast near Rockhampton.

It appears that the ships position is held tight up against the Coral of the Great Barrier Reef and it is the coral that is the only thing that is stopping 100s of tonnes of oil from escaping the stricken vessels holds.

As state and local authorities hoped for the best and prepared for the worst, Maritime Safety Queensland revealed a ''water plug'' was stemming the tide of environmental disaster. "Water pressure is keeping any spillage in place", a spokesman said. "It's wedged up against a coral shoal. Between these two things, it appears there's no oil leaking as a result." Today will be critical to containing the damage, authorities said.

An oil slick three kilometres by 100 metres escaped the damaged ship on Sunday, after it veered off course, apparently taken a short cut, into the well-charted reef late on Saturday.

The investigation will focus on why the ship appeared to shave a corner off a sea lane, saving a few nautical miles from its journey north from the port of Gladstone, and why authorities were not notified until two hours after it blundered onto the reef.

The oil slick appeared to ebb yesterday as authorities sprayed a chemical dispersant designed to break it up before it reached the central Queensland shore.

Low tides over the coming fortnight could prevent a speedy salvage operation. However, the personnel and equipment needed to deal with this oil spill were being amassed yesterday in the event the carrier breaks apart.

Rockhampton's mayor, Brad Carter, said the current would probably carry oil into the environmentally sensitive, largely inaccessible Shoalwater Bay.

"We believe that once you get north of Stockyard Point there's probably only one beach, called Freshwater Bay, where you can get road access", Mr Carter said. "The removal of any oil-contaminated material would be a logistical nightmare."

Mr Carter wanted guarantees from state and federal authorities that such a potential disaster could never occur again on the Great Barrier Reef.  "I've had no further information as to why this vessel was so far off course," he said. "It does look like there was the opportunity to get a bit of a short cut through there."

Svitzer Salvage is bringing up to 25 people to Gladstone from across Australia, Asia and Europe to work on the salvage operation. A spokesman said most would arrive in the area by the end of today and would work mainly from the stranded vessel.

The chief executive of the Australian Maritime Safety Authority, Graham Peachey, said "We will be investigating very thoroughly what happened. This is an extraordinarily valuable area in the Great Barrier Reef. It is pristine and it needs to be protected".

The Environment Minister, Peter Garrett, said he would work with the Transport Minister, Anthony Albanese, to ''consider whether additional measures such as piloting, are required for the management of shipping in the Great Barrier Reef''.

The Maritime Union of Australia said the lack of mandatory piloting through parts of Commonwealth waters showed self-regulation of the industry had not worked.

The Greens leader, Bob Brown, who flew over the scene yesterday, said Australian taxpayers should not have to pay for the clean-up.

Editors Comments: What on earth was a tanker that size doing anywhere near the Great Barrier Reef ?  Thank goodness it is over 1100kms away from our part of the Great Barrier Reef, so no risk of pollution here but nevertheless it does make you wonder who was steering doesn't it?

I heard quite an interesting solution to the problem of compensation for the damage to this southern part of the Reef yesterday.  You may think it's a little radical but it does have a touch of justified retribution about it.  See what you think.  Get all the crew to safety, remove the oil and any other harmful pollutants and simply sink the vessel just outside the existing reef area and let the coral spread across to inhabit the resulting wreck.   It would be appear to be safer than letting the vessel carry on it reckless way (sorry no pun intended) and puts something back for the reef and its inhabitants to expand into while their own bit of the reef recovers (if it can).   It would also act as a deterrent for anyone else who fancies taking a short cut in the future wouldn't it ?  What do readers think ?