Wednesday, April 28, 2010

US oil spill 'may be one of the worst in history'

From the Sydney Herald

US oil spill 'may be one of the worst in history'

The Gulf of Mexico oil rig disaster will develop into one of the worst spills in US history if the well is not sealed, the coast guard officer leading the response has warned.

BP, which leases the Deepwater Horizon platform, has been operating four robotic submarines some 1500 metres down on the seabed to try to cap two leaks in the riser pipe that connected the rig to the wellhead.

But the best efforts of the British energy giant have yielded no progress so far, and engineers are frantically constructing a giant dome that could be placed over the leaks as a back-up plan to try and stop the oil spreading.

Time is running out as a huge slick with a 965km circumference, seen in satellite images released by NASA, has moved within 34km of the ecologically fragile Louisiana coast despite favourable winds.

The US authorities said they were considering a controlled burn of oil captured in inflatable containment booms floating in the gulf to protect the shorelines of Louisiana and other southern states.

''I am going to say right up front: the BP efforts to secure the blowout preventer have not yet been successful,'' Rear Admiral Mary Landry told a press conference on Tuesday, referring to a 450-tonne machine that could seal the well.

Asked to compare the accident to the notorious 1989 Exxon Valdez oil tanker disaster, Landry declined but said: ''If we don't secure the well, yes, this will be one of the most significant oil spills in US history.''

The US government promised a ''comprehensive and through investigation'' into the deadly explosion that sank the platform and pledged ''every resource'' to help stave off an environmental disaster.

The rig, which BP leases from Houston-based contractor Transocean, went down last Thursday 209km southeast of New Orleans, still burning off crude two days after a blast that killed 11 workers.

The widow of one of the dead crew members has filed a lawsuit accusing the companies that operated the rig - BP, Transocean and US oil services behemoth Halliburton - of negligence.

The blast created a slick that could reach Louisiana's wetlands - which are a paradise for rare waterfowl and other wildlife - within days if the winds change.

BP has sent a flotilla of 49 skimmers, tugs, barges, and recovery boats to mop up the spill, but their efforts were hampered at the weekend by strong winds and high seas.

A rig is on stand-by to start drilling two relief wells that could diverting the oil flow to new pipes and storage vessels.

But BP officials say the relief wells will take up to three months to drill, and with oil gushing into the Gulf of Mexico at the rate of 160,000 litres a day the dome is seen as a better interim bet.

''They started working on the fabrication of this dome structure fairly recently and it's estimated it will take two to four weeks to build,'' US coast guard spokesman Prentice Danner said.

''This is the first time this has ever been done. This idea didn't exist until now. It has never been fabricated before.''

The exact dimensions and design of the dome were still being worked out, but officials said it would be similar to welded steel containment structures called cofferdams that are already used in oil rig construction.

''If you could picture a half dome on top of the leak and the oil collects inside of this dome and is pumped out from there, that is the idea behind it,'' explained Danner.

BP chief executive Tony Hayward expressed confidence an environmental disaster would be averted as he acknowledged that strong first-quarter results on Tuesday had been overshadowed by the ''tragic accident''.

Improved weather conditions, ''combined with the light, thin oil we are dealing with, has further increased our confidence that we can tackle this spill offshore''.

According to National Oceanic and Atmospheric Administration experts participating in the spill response, the slick is ''very thin'' and consists of ''97 per cent sheen''.

Northwest winds blowing the oil away from Louisiana were predicted to keep the slick from reaching shore through Thursday at least.

Communities in southern US states along the Gulf of Mexico were nonetheless bracing for the possibility of polluted beaches and fisheries that are crucial to the region's economy.

Louisiana governor Bobby Jindal, meanwhile, ordered all flags over state buildings to fly at half-staff through sunset May 3 as a token of respect for the 11 crew members who remain missing and are presumed dead.

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