The clean-up operation is fully underway for the oil spillage from Transocean’s Deepwater Horizon rig.

BP is assisting with the cleanup operation following the fire and subsequent collapse of Transocean’s semisubmersible drilling rig Deepwater Horizon offshore Louisiana, with one third of the world’s dispersant ready to be deployed to help prevent the oil spill spreading.

Based approximately 40 miles offshore Louisiana on Mississippi Canyon block 252, and 130 south east of New Orleans, the rig caught fire on Tuesday 20 April, and sank on Thursday 22 April. On 23 April, the search and rescue operation was called off – of the 126-member crew, 115 were safely evacuated. Eleven remain missing.

BP Exploration & Production is the rig’s lease operator. Tony Hayward, BP Group Chief Executive, said: “We are attacking this spill on two fronts – at the wellhead and on the surface offshore. The team on the ground and those at sea have the Group’s full resources behind them.”

The resources include 100,000 gallons of dispersant, 32 spill response vessels, and five aircraft for dispersant deployment.

On a surface level, the team has recovered more than 1,000 barrels of an oil-water mix – of which the vast majority was water – collected by skimming vessels, containment booms, and the application of dispersants.

BP is also working with Transocean to permanently secure the well underwater, using sub-sea equipment and remotely-operated vehicles.

Steve Benz, President and CEO of the Marine Spill Response Corporation (MSRC), said: “At BP’s request we are mounting the single, largest response effort in MSRC’s 20-year history. The many years of working together with BP on drills and exercises has proved invaluable to us as we move forward on this response effort.”

Steven L. Newman, President and Chief Executive Officer of Transocean Ltd, said on the 23 April, when it was announced the search and rescue operation had been suspended: “As the nation and everyone in the Transocean family mourns the tragic loss of these people, our deepest sympathies are with their families and friends today.

“Transocean is doing everything we can to meet their needs during this difficult time, and our family response team members are in close contact to provide all necessary support. I would once again like to express our gratitude to the U.S. Coast Guard, BP and everyone involved for their exhaustive search and rescue efforts, despite this very sad outcome.”

Transocean is the world’s largest offshore drilling company and has a fleet of 139 mobile offshore drilling units. The Deepwater Horizon rig was built in 2001 and is capable of operating in harsh environments and water depths up to 8,000ft.

The cause of the fire is still being investigated.