Originall yposted by Jennifer Dlouhy - Houston Chronicle - August 9, 2010
WASHINGTON — Lawmakers eager to prevent another oil spill in the Gulf of Mexico — and prove to voters that they’re responding to the Deepwater Horizon disaster — are insisting on new standards for blowout preventers, a last line of defense against runaway wells.
Federal regulators at the Interior Department also are mulling new rules that could boost the chances the 450-ton safety devices would stop a blowout by shearing through pipe and cutting off the oil and natural gas. The mandates aim to respond to vulnerabilities revealed when the five-story blowout preventer at BP’s doomed Macondo well failed to block an estimated 4.9 million barrels of oil from gushing into the Gulf of Mexico over 85 days. But petroleum engineers warn that mandates for extra triggering mechanisms and more pipe-cutting rams might not have helped stop the oil at BP’s well, and industry officials say some proposed rules might require blowout preventers too big to fit on some drilling rigs. Oil and gas industry leaders want lawmakers and regulators to wait for a full investigation of why the preventer at BP’s well failed on April 20 before setting new rules that could trigger a top-to-bottom redesign of the devices. American Petroleum Institute President Jack Gerard says the rush to regulate is tantamount to “going into surgery without a diagnosis.” “While the focus has been on the blowout preventer, even those on site will tell you we don’t yet know the exact cause,” Gerard said. “A legislative response to the spill is appropriate,” he said, but hasty changes increase the potential of introducing new risks into the drilling process.
BP’s preventer failure
Invented nearly 90 years ago, blowout preventers, often called BOPs, are giant stacks of valves installed on top of land and sea wells to help maintain control during unexpected pressure changes. They play their most vital role in emergencies, when metal shear rams are triggered to slash through the drill pipe and casing. A device called a blind shear ram is supposed to slam shut and seal off the open hole. At BP’s Macondo well, that didn’t happen, despite at least three attempts to activate the rams — first by workers on the drilling rig, next by a “deadman switch” automatically triggered whenever the preventer’s power, communication and hydraulics connections are severed, and finally by remote-controlled underwater vehicles. Final conclusions about what went wrong may depend on an autopsy of the blowout preventer at Macondo once it is exhumed from the ocean floor. One theory is that an extra piece of drill pipe or other debris flew into the space between the rams and prevented them from cutting and closing fully. Lawmakers insist blowout preventers should have more built-in redundancy, including an additional blind shear ram that could sever and seal off open pipe even if debris blocked another ram. “We know blowout preventers are not foolproof — not even close,” said Rep. Henry Waxman, D-Calif. But, he said, new requirements for redundant rams and backup control systems could increase their reliability. The House voted last month to require the Interior Department to issue new regulations requiring a second set of blind shear rams on BOPs, along with redundant emergency backup control systems for remotely activating the devices whenever communications with the rig are severed. That could include $500,000 acoustic triggers already required by Brazil and Norway, though U.S. drilling experts have questioned their effectiveness.
The House-passed bill also contains new mandates for the wells themselves. It would require new rules for cement barriers and at least two other physical barriers at wells — all designed so that if one doesn’t work, it doesn’t cause a cascade of failures. Industry leaders chafe at Congress’ push for new requirements. “Bills that mandate technical and engineering characteristics of blowout preventers are examples of Congress overreaching their expertise,” said Lee Hunt, president of the International Association of Drilling Contractors. API’s Gerard said Congress should leave BOP engineering to technical experts. Waxman counters that the House-passed bill only lays out broad goals for future requirements and leaves details up to federal regulators. “We were careful to provide regulatory flexibility so that the minimum requirements can evolve as the technology improves,” he said.
Size could be an issue
Drilling contractors warn that beefed-up blowout preventer requirements could cause the devices to grow so large they won’t fit inside shallow-water drilling rigs, where they are installed and used onboard. “A rig is very intimately designed for spacing and weight,” noted Jim Noe, a vice president of Houston-based Hercules Offshore. Greg McCormack, director of the University of Texas Petroleum Extension Service, estimated that installing an additional shear ram could add as much as 10 feet to the BOP stack. “It’s going to mean a lot of retrofitting,” McCormack said. “For some of these older rigs, it’s not going to be profitable.” Before the House passed its drilling bill, industry officials implored lawmakers to narrow the requirements to wells deemed “high risk” by regulators — or at least rule out shallow-water drilling where the BOP is easily accessible above the sea. The final legislation — which has not passed the Senate — does not distinguish between well types. Drilling experts say the focus on blowout preventers misses bigger problems of poor training and well design. “It doesn’t do any good to continue to stack blowout prevention equipment on top of a well bore that’s improperly designed to begin with,” said Gene Beck, a petroleum engineer with Texas A&M. McCormack said there is not enough focus on training. “You can put all these mechanical devices in,” he said, “but, at the end of the day, people have to operate them.”