BP Plc’s use of a tight-fitting cap to shut off oil flowing from its Gulf of Mexico Macondo well may be the solution the company has sought since the undersea gusher was triggered by an explosion three months ago.
“We are pleased that no oil is currently being released into the Gulf of Mexico and want to take all appropriate action to keep it that way,” National Incident Commander Thad Allen said in a statement today.
Three days of tests on the capped gusher have so far shown no problems that would prompt BP to reopen the well, Doug Suttles, chief operating officer for exploration and production for BP, said today in a conference call from Houston.
The company will monitor the well closely, running a continuous series of seismic, pressure and temperature tests to make sure it isn’t damaged, Suttles said. U.S. government officials will review the test data daily to decide whether it’s safe to keep the well closed, Allen said.
Scientists fear that a seep detected near the well may be a sign of a hidden leak, the Associated Press reported today, citing an unnamed federal official familiar with oversight of the spill. The official provided no additional details to the press service.
On July 17, BP, based in London, said it will investigate bubbles coming from one of the valves on the well cap near the seabed. Kent Wells, BP’s senior vice president for exploration and production, said the bubbles might be nitrogen or methane and were “quite normal,” but would be studied “with an abundance of caution.”
BP declined to comment on the Associated Press report. The company continues to work closely with the government to review the data and decide on the best course of action, John Curry, a BP spokesman, said.
As long as no leak is confirmed, BP plans to keep the well sealed until it is permanently plugged with cement next month, preventing any more oil from flowing into the sea.
Stopping the flow of oil from the well represents a significant success, Tad Patzek, chair of petroleum and geosystems engineering at the University of Texas at Austin, said in an interview.
“BP is finally doing the right thing,” Patzek said. “The best thing to do now is to wait for another couple of days and watch the well, and see how the pressure evolves, how it stabilizes, and draw conclusions from it.”
Any negative data may prompt BP to reopen the well and resume capturing the oil gushing from the seabed. Resuming the containment process might take three days, during which oil would again be spilled into the Gulf, Suttles said.
The Macondo well has produced the biggest oil spill in U.S. history, spewing 35,000 to 60,000 barrels of oil a day from a mile-deep in the water, according to a U.S. government-led panel of scientists.
BP bolted a 40-foot (12-meter) stack of valves on top of the well that it used to stop the flow of oil July 15, when it began testing for damage.
The company, taking advice from outside scientists ranging from a nuclear bomb inventor to space experts, failed repeatedly in earlier efforts to stop the leak or plug the well. Plans to contain the spewing oil with a 40-foot-tall steel box failed when the box became clogged with ice crystals.
An effort to plug the well from the top, called “top kill,” was called off after days of pumping mud into the well could not stanch the flow of oil, and a so-called junk shot injection of golf balls and rubber scraps was unable to stop it.
The main purpose of the new cap sitting on the top of the well, built with assistance from Transocean Ltd. and Cameron International Corp., was to help channel more oil to the surface if the well could not be sealed, Allen has said.
The previous, loose cap allowed BP to capture about 25,000 barrels a day of oil from the well, while still letting some escape. If it’s necessary to reopen the well, the new installation would enable vessels to eventually contain about 80,000 barrels, Suttles said today.
President Barack Obama praised the new cap on July 15 as “good news,” with a caveat.
“It’s important that we don’t get ahead of ourselves here,” Obama said. “We’ve got an enormous amount of work to do, and people down in the Gulf, particularly businesses, are still suffering.”
BP and government officials have emphasized that the only permanent fix for the leak is to drill relief wells to intercept Macondo and fill it with cement.
The first relief well has reached a depth of 17,864 feet and could intercept the leak before the end of July. Then BP will begin pumping drilling mud and cement into the well to plug it, an operation that may be completed within days or continue through mid-August, Suttles said today.