BP carries out 'BOP brain surgery'

BP is carrying out surgery on the “brain” of the subsea blowout preventer (BOP) it recovered yesterday, with plans to reinstall it in the hopes it will provide accurate readings of the pressures inside the Macondo oil well blowout in the deep-water Gulf of Mexico.

A better handle on the well pressures may help BP refine its options for bringing the well under control sooner rather than later.

“We retrieved what is called the yellow pod, this is the sort of brain on the blowout preventer, and brought it to the surface,” chief operating officer Doug Suttles said yesterday afternoon at a press conference in Houma, Louisiana.

“We are currently working to re-wire that brain. We’re going to redeploy back on the blowout preventer and we hope that will allow us to read pressures inside of it.”

Depending on the information derived from the yellow pod, including the internal pressure in the BOP, BP may be able to try one of two options to bring the well under control.

BOP II

First, BP could try to shear the lower marine riser package and install a second BOP on top of the first, which appears to be too damaged to close the well.

It is understood that the BOP on board the Discoverer Enterprise, which is on location, will be used.

According to Transocean's fleet inventory, the BOP is a Hydril 18¾ inch 15,000 psi, six-ram system with a Cameron 15,000 psi wellhead connector.

Depending on the pressures, BP also may be able to tap into the existing BOP and circulate heavy fluids to kill the well.

Suttles said BP has already manufactured the equipment it would need to inject the fluid and it is being shipped to the location.

Either course of action could likely be done faster than the 90 days Suttles estimated it would take for the relief well to intercept the Macondo bore but neither has been done before at this depth.

“We don’t take any action which could make the spill worse,” Suttles cautioned. “Gathering pressure data from inside the blowout preventer is part of that.”

A video outlining about BP's efforts to halt the Macondo flow is available here.

Macondome

BP has started lowering a containment dome to the seabed. The dome - the first of three - is designed to cover the largest leak at the end of the marine riser.

The "Macondome" traveled to Mississippi Canyon Block 252 on the Edison Chouest Offshore's M/V Joe Griffin on Wednesday.

BP will now bring in Transocean’s drillship Discoverer Enterprise and connect the 70-tonne structure, which measures 14 feet by 24 feet by 40 feet, to the ship via a rigid 2" steel riser with a 6 5/8" drill string.

That operation will take about two days and BP hopes to have the system working by early next week.

BP spokesman Robert Wine said: "The plan is to pump sea water down the annulus to help lift the oil - oil is lighter than sea water - and to keep it fairly warm.

"It's a fairly gassy oil - it has a gas-to-oil ratio of about 3000 - so a major challenge for at least the first 2000 feet is hydrate management. It's at those first couple of thousand feet where the risk of gas hydrate formation is the highest."

Wine added that methanol will be injected at the top of the riser to help reduce the risk of hydrate formation.

Remotely-operated vehicles (ROVs) will assist with the operation. Wine did not know whether ROVs currently working on attempting to activate the Deepwater Horison's crippled BOP would be called to the site to assist.

Gas will be separated out, while oil - the Discoverer Enterprise has a storage capacity of 128,000 barrels - will be shuttled to shore and be stored at one of BP's Gulf coast refineries.

Suttles warned of potential “start-up trouble” since a similar operation has never been done at this water depth.

“We’ll have to learn how to make it operate,” he said.

Work continues on two more domes, one of which is set to go over a smaller leak at the juncture of the riser and the other on the lower marine riser package.

Valve

Earlier this week, BP capped one of the three leaks identified in the Macondo infrastructure, installing a valve over the end of the broken drill pipe that sticks out beyond the end of the riser.

Suttles said the capping operation involved crews first cutting the jagged end of the drill pipe, which extended beyond the end of the broken riser.

They then fabricated and installed the valve.

But Suttles has said capping the drill pipe has not reduced the volume of oil into the Gulf of Mexico from the blownout well.

Landfall

Rear Admiral Mary Landry confirmed that oil had hit the beach at Chandeleur Island.

The Coast Guard has refused to release information on the size of the slick, with Landry repeatedly saying such a figure would be misleading because the slick changes size and shape.

It is believed that at least two offshore gas processing platforms, which move about 6.2 million cubic feet per day, have been shut in due to the spill.

Suttles said “good weather” has aided efforts to place 42,000 feet of booms yesterday to contain the spread and light fires to burn off more of the oil on the water’s surface.

Suttles said over 700,000 feet of total boom is now deployed.

The Coast Guard has begun controlled burns on the spill again and Suttles estimated that “several thousand barrels” of oil have been consumed over the last couple days.

Dispersant

Though planes are still dropping dispersant on the surface slick, officials are analysing the effectiveness of the subsea dispersants applied at the source of the leaks and no decision has been made whether to proceed with untested method.

People living near the spill zone are becoming increasingly concerned about the possible effects of the dispersants in the water.

Crews are using the same two dispersants, Corexit 9500 and Corexit EC9527A above and below the water, Suttles said.

Corexit 9500 can cause skin and respiratory tract irritation, according to material safety data sheets provided by the Coast Guard.

Its overall human hazard potential is “moderate,” the sheets state, while the potential environmental hazard is listed as “low”.

Corexit EC9527A can also irritate the skin and respiratory tract, but it also can damage the liver and central nervous system.

Its human hazard potential is “high” and potential environmental hazard is “moderate”, according to the material safety data sheet.

Industry change

BP executive vice president for the Americas and Asia Robert Dudley said yesterday that the leak would change the global offshore industry "forever".

"Once the clean up is done, the investigation is complete and the lessons learned and spread around the globe from this activity occurring (at) the frontiers of human effort, we will consider the trade-offs of exploring for new sources of domestic energy in the frontiers of deep water," Dudley told business leaders in Boston.

A BP spokesman later told Reuters that Dudley’s comments referred to society’s commitment to oil exploration and not to BP’s own exploration and development work.

Spud

The Transocean semi-submersible rig Development Driller III spudded the first of two planned relief wells shortly after 3pm local time on Sunday.

The well will take between two to three months drill to about 18,000 feet and then intercept the blown-out well.

BP said that the well reached 6805 feet below sea level on Wednesday, or about 1800 feet below the seabed. A 28-inch cashing string has been set and cemented and the well is drilling ahead.

The UK supermajor has decided to bring in a third rig, the Transocean semi-submersible rig Development Driller II, to spud a second relief well.

The rig will arrive on location in about 10 days and will "race" to spud a second relief bore.

Fury

This week US Senate Democratic Leader Harry Reid voiced support for calls to raise the liability cap on companies responsible for oil spills from $75 million to $10 billion.

Calls to increase the spill penalty also drew support from the White House, with Obama press secretary Robert Gibbs saying the president would be open to the proposal.

Democratic Senator Bill Nelson proposed lifting the liability cap.

Disaster

The Macondo well - a discovery well which was to be temporarily abandoned ahead of later completion as a subsea producer - blew out on 20 April.

The well had been drilled to 18,000 feet by the rig Deepwater Horizon. An explosion rocked the semisub before the rig was engulfed in flames.

The semisub sank on 22 April, extinguishing the blaze.

The initial cause of the accident is still unknown, although a senior Transocean executive, Adrian Rose, earlier indicated it seems likely the well blew out.

“We don’t know what caused the accident,” he said. When asked if the incident involved a blowout, he replied: "Basically, yes."

Eleven of the 126 crew on board the Deepwater Horizon at the time of the explosion are missing, presumed dead.

Drilling giant Transocean has confirmed nine of its employees are among the missing. Two worked for services outfit Smith International and Schlumberger's M-I Swaco joint venture.