OGJ Senior Staff Writer
HOUSTON, May 4 -- A subsea containment system to collect oil leaking from a Gulf of Mexico deepwater well off Louisiana was scheduled to be operational in about 6 days, Doug Suttles, chief operating officer of BP Exploration & Production Inc., told reporters during a May 4 news conference in Mobile, Ala.
Transocean Ltd.’s Deepwater Horizon semisubmersible drilled the Macondo well on Mississippi Canyon Block 252 in 4,992 ft of water. An Apr. 20 explosion and fire left 11 crew members missing and presumed dead. The Deepwater Horizon sank on Apr. 22.
An estimated 5,000 b/d is leaking into the gulf from three subsea points, Suttles said. BP planned to put a shutoff valve on the drill pipe, perhaps as early as May 4, which would reduce the number of oil leak sources from three to two. But Suttles said the volume of oil being spilled probably would not change.
Spill response officials estimate the planned subsea containment system could collect as much as 85% of oil rising from the seafloor. It will be the first time this type of system has been used at this water depth.
Meanwhile, Transocean’s semisubmersible Development Drilling III started drilling a relief well on May 2. The relief well, expected to take 2-3 months to complete, will be drilled to 18,000 ft—the same depth as the first well from which oil is leaking.
Controlled burns on open water to eliminate areas of emulsified also were expected to be resumed May 4. Suttles said an initial test burn in late April involved 100 bbl, but he believes future burns could involve from 500-1,000 bbl for each burn.
No oil on shore yet
US Coast Guard Rear Adm. Mary Landry said May 4 that officials have yet to confirm that any oil has reached shore despite earlier projections that oil might reach Louisiana in the Mississippi River delta area on Apr. 30. A shift in wind and waves apparently has prevented that so far.
“We have been given a gift of time,” Landry said. The leading edge of the spill is rainbow sheen consisting of an oil and water mixture, she said.
Cause of the rig accident and failure of the blowout preventer (BOP) to shut off the oil flow remain under investigation by various companies and government agencies.
MMS issues safety alert
The US Minerals Management Service and USCG have issued a safety alert asking operators and drilling contractors to inspect their equipment and review their procedures.
Among a list of safety recommendations issued Apr. 30, the MMS and USCG asked operators and contractors to examine all well-control equipment (both surface and subsea) to ensure that equipment has been properly maintained and is capable of shutting in the well during emergency operations.
MMS and USCG also ask that all rig drilling, casing, and completion practices be reviewed to ensure that well-control contingencies are not compromised at any point while the BOP is installed on the wellhead. They also ask operators and contractors to review all emergency shutdowns and dynamic positioning procedures that interface with emergency well-control operations.
Contact Paula Dittrick at firstname.lastname@example.org.
BP's spill containment system slated to leave dock on May 5