Senators at Hearing Focus on Well Pressure
Wednesday, May 12, 2010
Senators zeroed in Tuesday on unusual pressure readings, bypassed tests and the application of cement barriers as possible factors in the explosion of the Deepwater Horizon offshore drilling rig and the growing oil spill in the Gulf of Mexico.
"We don't know yet precisely what happened on the night of April 20," BP America President Lamar McKay told two Senate panels investigating the disaster. "But what we do know is that there were anomalous pressure test readings prior to the explosion," which may have raised concerns about the stability of the well.
A well blowout and rig explosion that night killed 11 workers and started oil spilling from the head of BP's Macondo well a mile below the Gulf's surface.
Drilling on the exploratory well wrapped up April 17, allowing rig operators and cementing contractors from Halliburton Co. to begin the final steps of plugging up the open well hole so that it could be temporarily abandoned until a full production facility could be hooked up later.
Steven Newman, the CEO of the rig owner, Transocean, told senators that "without a disastrous failure" of cement plugs or cement casing enclosing the well, "the explosion could not have occurred."
F.E. Beck, a petroleum engineer and associate professor at Texas A&M University, told the Senate Energy and Natural Resources Committee that the multiple cement barriers failed to check the blowout -- an uncontrolled flow of hydrocarbons from the wellhead.
"For a blowout to occur, multiple barriers must fail or be rendered useless through human error," Beck said.
But Tim Probert, Halliburton's chief health, safety and environmental officer, insisted that "oil rigs don't explode because of a failure of a cement job."
He argued that Halliburton had completed cementing work about 20 hours prior to the "catastrophic loss of well control," and had followed -- under contractual obligation -- the dictates and direction of BP.
Two subsequent tests verified the integrity of the casing and seals at the well bore, Probert said, though a third test of the cement barrier's effectiveness was skipped.
Sens. Tom Udall, D-N.M. and Jeff Sessions, R-Ala., questioned the decision to remove heavy fluid called drilling mud from the pipe at the well hole and allow it to be displaced by seawater before installing a final cement plug.
The sequence often is the opposite, with the cement plug being installed before the mud is removed. But Probert said the procedure was not unusual and that the sequence has been performed previously in the Gulf of Mexico.
Congress plans at least a dozen hearings as part of an aggressive congressional investigation of the Deepwater Horizon disaster. The executives from BP, Transocean and Halliburton are scheduled to appear today before a House Energy and Commerce investigative subcommittee.
The Coast Guard and the Minerals Management Service also conducted hearings that began Tuesday and continue today in Kenner, La., as part of the federal probe of the incident.
Sen. Jeff Bingaman, D-N.M., the head of the Senate energy committee, predicted that the "examination of what happened ... will likely discover that there was a cascade of failures: technical, human and regulatory."
Senators scolded the business leaders for "finger-pointing" and shifting blame for the disaster Tuesday, with Sen. Amy Klobuchar, D-Minn., suggesting the executives were behaving like children arguing over who hit a baseball through a broken window.
'A Texas two-step'
Sen. Robert Menendez, D-N.J., said he could already "see the liability chase that's going on," which he described as "a bit of a Texas two-step" over who's responsible.
"BP says Transocean, and Transocean says Halliburton," Menendez said.
Sen. Lisa Murkowski, R-Alaska, and Sen. Blanche Lincoln, D-Ark., questioned the adequacy of current inspections of blowout preventers, 450-ton devices used on oil and gas wells worldwide as a last-ditch safeguard against spills.
Those inspections -- required every 14 days -- evaluate whether the device can hold pressure, but they do not test whether key components, called shear rams, can successfully pinch through and close leaking pipe in case of a blowout.
"There needs to be a better program for testing shears independently to better understand what force is being generated and what force is required," said Elmer Danenberger, the former chief of the Minerals Management Service's offshore regulatory program.
Sessions of Alabama questioned whether the offshore oil industry and its federal regulators had grown complacent because of a relatively good track record.
"Maybe there's been some laxity or complacency or overconfidence," he said.
Senators also questioned the adequacy of the industry's preparation for a disaster and noted that a spill response plan designed by BP never envisioned the failure of the blowout preventer.
"With so much of the region's economy at risk, why were exploration plans and environmental documents prepared with little to no analysis of the threat of a serious spill?" asked Sen. Barbara Boxer, D-Calif., the chairman of the Senate Environment and Public Works Committee. Murkowski said she was stunned that the industry hadn't researched the effectiveness and safety of injecting chemical dispersants deep underwater at the source of gushing oil.
Both Sessions and Sen. Arlen Specter, D-Pa., wondered why a containment dome -- built hastily after the spill in a so-far-unsuccessful effort to trap the leaking oil -- wasn't constructed and at the ready in case of any disaster.
Source: Houston Chronicle
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