The US government ordered certain ships working on the Gulf of Mexico oil spill back to port yesterday, amid fears that a brewing storm could force a mass evacuation and derail efforts to plug BP's runaway well.
A full-scale evacuation could delay by up to two weeks the final operation to plug BP's runaway well, which has unleashed millions of barrels of crude on Gulf Coast shorelines in one of America's worst ever environmental disasters.
"Activities that are under way for storm preparedness include evacuating specialised vessels from the path of any severe weather to prevent damage and ensure that oil recovery operations can resume as soon as possible after a storm," a Coast Guard statement said.
With no crews on site to monitor pressure inside the well, top US official Admiral Thad Allen has warned that the cap that has prevented any toxic crude from entering the sea for the past week may have to be opened up again or even removed.
Storm warnings were extended yesterday from the Caribbean around the Florida Keys to the Gulf Coast, but there was no immediate order from BP or the US government to suspend operations entirely and pull staff back to shore.
If the depression developing near the Bahamas takes aim at Louisiana it will delay a so-called "static kill" to seal the well with cement originally planned for this weekend.
Officials have warned it will take up to five days to get some of the biggest vessels, in particular the massive drilling platforms working on relief wells, back to port.
"We've always said we need 120 hours in advance to be able to start redeploying them and then the total time off-scene would be anywhere between 10 and 14 days," Admiral Allen said on Wednesday.
As for what to do with the cap, this would be "a judgment call based on the risks," he added.
The first relief well was expected to intercept the damaged well as early as next week but if the storm hits that could be more like mid-August and any final operation to seal the well with cement might be delayed until September.
The storm threat was already delaying progress as work on the final casing of the relief well was suspended so a special plug called "a storm packer" could be fitted to stabilise it.
A full evacuation would be a huge blow for local residents who already see efforts to choke off the well as too little too late, with hundreds of miles of coastline in all five Gulf states already fouled.