Louisiana Oil Rig :- Engineers Build Dome to Contain Spill

Engineers working for BP are rushing to build a giant dome to help contain oil spilling from the Deepwater Horizon rig, which collapsed off the coast of Louisiana last week. A slick measuring 48 miles by 39 miles at its widest points has developed 30 miles off the ecologically fragile Louisiana coast.
Once completed, the dome will be submerged above the area of seabed from which the oil is gushing. It is hoped the dome will catch the oil as it rises, which could then be pumped out.
Similar devices were tried when Hurricane Katrina swept through the Gulf in 2005 but have never been used in water this deep. Tony Odone, a spokesman for BP, told the Times: "They have been used in shallow water before. They contain the oil in that dome and then suck it up. "
"The ROVs [remotely operated vehicles] will continue trying but we are trying to get these other things activated as quickly as possible, too."

Until the dome is ready, underwater robots will battle to stop 42,000 gallons of oil a day from streaming into the Gulf of Mexico from a sunken rig. A slick measuring 48 miles by 39 miles at its widest points has developed 30 miles off the ecologically fragile Louisiana coast since the rig sank last week following an explosion that apparently killed 11 workers. BP, which leases the stricken Deepwater Horizon platform, has been using four robotic submarines to try to fully activate the giant 450-tonne blowout preventer and shut off the flow of oil.

But BP officials suggest the unprecedented operation, which is being conducted remotely a mile down on the seabed, is a longshot and admit they may have to resort to drilling relief wells, a process that would take far longer.
"It is possible that it could take two to three months for a relief well to be drilled," Bill Salvin, a spokesman at the joint information centre set up by BP and US-based platform contractor Transocean, said. Mr Salvin also mentioned a "worst-case scenario" that would see recovery teams "lose total control of the well" and cause the oil to start leaking at a much quicker rate.

BP has also dispatched 17 skimming vessels to mop up the crude oil spilling from two leaks in the 1,500 foot riser that connected the rig to the wellhead, but those efforts have been hampered by thunderstorms and high seas. Officials said one of the undersea robots had sent back visual images of sunken tanks containing 700,000 barrels of diesel - the first report of the "pontoons" that were stacked on the rig before the sinking.
"We have no evidence of diesel emanating from the pontoons at this time," said a spokeswoman for the joint information centre.

The spill won't stop the deepwater scramble for oil. In recent years BP has cast itself as the daredevil pioneer of deepwater drilling in the Gulf of Mexico, Brazil and off the coast of Africa. The deepwater oil platform burned for more than day after a massive explosion, turning a deadly blast into an environmental emergency. But as it continues to spew 42,000 gallons of oil into the ocean per day, BP's extreme measures to stem the spillage show just what kind of high risk and difficult conditions oil companies are working under to tap the world's remaining reserves.
The deepwater nature of the well means the clean-up operation is more complex, but as oil majors continue to push the boundaries of exploration, how far might pioneering techniques be to blame for this type of accident? Although investigations are still ongoing, it looks likely that the rig's failure was due to problems with its "blow-out preventer" – a giant system of pipes and valves that helps withstand pressure surges. Although all rigs are fitted with the 450-ton safety device, the depth and harshness of deepwater conditions can make a build-up of pressure more severe.

BP and Transocean are quick to point out that deepwater drilling has been going on for decades, with Horizon's failure the worst in 23 years. But observers still note that a disaster could not come at a worse time for President Barack Obama's administration, as he pushes for more deepwater exploration licences near the East Coast and Alaska.
"The timing was impeccably bad with Obama contemplating expanding offshore drilling," according to US investment bank Tudor Pickering Holt. "The longer it takes to control the well the louder the environmental argument will be for less access."
However long it takes to contain the spill and its consequences, the incident is unlikely to discourage companies from scrabbling around the deepest, darkest corners of the earth for difficult oil. It won't stop deepwater drilling.