All 13 men working on the site, owned by US company Mariner Energy, have been rescued, after a helicopter spotted a blazing structure 100 miles from the Louisiana coastline.
“Thirteen people were seen huddled together in the water wearing gumby suits or immersion suits, water protection suits, so we were able to confirm that all people were accounted for,” said John Edwards, a Coast Guard spokesman.
However, Mariner confirmed that the explosion was not triggered by a blowout, which was the cause of BP’s disaster.
Initially, Mariner reported there a mile-long oily sheen on the water around the platform, the Coast Guard said. But several hours later after the fire was extinguished, the sheen had disappeared.
“The boats and the aircraft on scene cannot see a sheen,” Coast Guard captain Peter Troedsson told a news conference in New Orleans.
Mariner Energy’s workers were only conducting maintenance on the site rather than drilling into the ground, so there was thought to be only a slim chance of a leak.
But BP made a similar original assessment that there was no oil in the water after the Deepwater Horizon rig exploded and sank, killing 11 men, on April 20. It eventually gushed 5m barrels into the ocean, although the Mariner well is not believed to be as large or deep.
The US company has already sent out three ships to fight the fire and is expected to mount a full-scale oil spill response effort.
It is only five months since Apache, another US oil company, said it would assume Mariner’s $1.2bn (£780m) in debt and buy the company for $3.9bn in a cash and stock deal.
Mariner Energy’s share price dropped 2pc to $22.82 in New York and Apache’s shares also came under pressure, falling 2pc to $90.78.
The events came as BP began removing a cap from its damaged Gulf of Mexico oil well in preparation for a final attempt to plug it this month.
Oil is no longer flowing into the ocean after it was capped as a temporary solution, then sealed from the top. But the US authorities are insisting that extra measures are taken to ensure that it does not begin spewing again.
Once the cap is removed, BP can begin to replace the failed safety equipment – known as a blowout preventer – from the top of the well and replace it with a working device.
This is the prelude to a second operation to plug the well from the bottom using heavy liquids through an intersecting hole known as a relief well.
The structure is already plugged from the top with mud and cement.
It is unlikely that the removal of the cap will cause the flow to start again, but emergency response vessels are on the surface in case of another eruption from the damaged well.
The work was delayed earlier this week by high seas in the Gulf of Mexico. [via Daily Telegraph (UK)]