A View from Peter Fairley
BP Installs Spill Containment Scheme Number 4
A riser cap is capturing a fraction of the leak as BP seeks to optimize an imperfect seal.
BP is capturing oil at a rate of 1,000 barrels-per-day via its latest containment scheme–a cap and new riser installed on its gushing Gulf spill last night, according to federal response coordinator and Coast Guard Admiral Thad Allen. But video feeds confirm that far more crude is still spilling into the sea from under the cap–at least 11,000 barrels per day if one subtracts 1,000 bpd from the minimum flow estimate of the Deepwater Horizon spill released by a federal task force last week.
BP Americas chief operating officer Doug Suttles said in a media briefing this morning that the cap (BP containment scheme #4 by Carbon-Nation’s count) could ultimately capture over 90% of the leak. But Suttles and his company have proved unreasonably optimistic before, and could be once again.
That’s because effective capture requires a solid seal between the cap and the leaking riser from the Deepwater Horizon rig, whose destruction in April set off the spill. Unfortunately, a preparatory operation yesterday to cut away most of the leaking riser just above the Deepwater Horizon’s blowout preventer (BOP) left a jagged edge that could be tough to seal on. Allen told reporters that it may take 48 hours to optimize the system, and downgraded Suttles’ hopeful projection to a “goal.”
In a separate media briefing this morning BP senior vp for exploration Kent Wells said BP will ramp up suction slowly to avoid pulling in water that could combine with natural gas to form frozen hydrates and clog the pipe. To ward off hydrates they are also pumping hot water down around the new riser pipe, and methanol into the pipe.
BP’s official update this morning on its Lower Marine Riser Package repeated its now mantra-like disclaimer about the challenge of engineering on the fly in mile-deep waters:
Systems such as the LMRP containment cap never before have been deployed at these depths and conditions. The containment system’s efficiency, continued operation, and ability to contain the oil and gas cannot be assured.
Those caveats ring true given BP’s string of tech failures as Deepwater Horizon’s botched well has pumped over 20 million gallons of oil into the Gulf of Mexico:
- BP’s new riser cap must seal on a jagged edge because a cleaner-cutting diamond-tipped saw blade jammed in the leaking riser. BP used a massive pair of shears instead.
- Gushing oil and gas blew back mud and junk that BP pumped into the Deepwater Horizon’s BOP, defeating last week’s much-vaunted Top Kill operation.
- BP’s pre-Top Kill riser insertion tube (BP containment scheme #3) never caught more than one fifth of the total flow.
- Frozen hydrates of water and natural gas instantly clogged the coffer dam (BP containment scheme #2) that BP lowered over the BOP early last month.
- The BOP’s rams ignored instructions to close off the leak in the first two weeks after the accident (BP containment scheme #1), not to mention during the accident itself.
As always, BP has a menu of new tech options in the wings. Six other riser cap fittings can be tried for size in case the one now in place can’t seal. BP will also try to suck oil and gas out of the BOP via its choke and kill lines (through which it pumped drilling mud and junk during the Top Kill). And the troubled oil and gas giant says drilling of two relief wells to intersect and cement the leaking well at its deepest point–the only proven means of definitive offshore blowout control–remains on course for August.
However, based on the drubbing BP’s tech team has taken so far and the firm’s repeated caveats about operating at a mile under, it is increasingly tough for any oil and gas driller to deny the following conclusion: technology is not equal to the challenge of blowout control in deepwater conditions–at least not yet.
Peter Fairley, an independent journalist and editor of the Web journal Carbon-Nation, tracks energy innovation around the globe, from the solar-powered villages of Bolivia’s Cordillera to China’s mechanizing coalfields.