BP Stops Oil Spill in Test of New Containment Cap
HOUSTON, Texas, July 16, 2010 (ENS) – For the first time since BP’s Deepwater Horizon oil well blew out on April 20, oil has stopped spewing into the Gulf of Mexico. But the crisis is not over yet.
Following installation of a complex set of valves and pipes called a capping stack and in line with the procedure approved by National Incident Commander U.S. Coast Guard Admiral (ret.) Thad Allen and Unified Area Command, the well integrity test on the well began Thursday.
BP installed this capping stack on the Deepwater Horizon well where it is now being tested. (Photo courtesy BP)
The well integrity test will last at least six hours and could last up to 48 hours.
The test is needed to ensure that under high pressure, oil is not forced out through natural weak points in the geological formation of the sea floor, making the leaking uncontrollable.
“The only reason we would terminate the test very quickly,” said Admiral Allen, “is if we had a very low pressure reading, that would be indicative of the fact that oil was being released somewhere in the well bore out into the formation, we would not want that.”
“But as the pressure continues to rise, we will continue to monitor it,” he said. “And every six hours, we will evaluate where we are at based on the information that’s available at the end of 48 hours.”
BP explains that during the test, the newly placed “three ram capping stack” is closed, effectively shutting in the well.
All sub-sea containment systems taking the leaked oil to ships on the surface – the Q4000 and Helix Producer – have been temporarily stopped.
“Although it cannot be assured, it is expected that no oil will be released to the ocean during the test,” BP said in a statement. “Even if no oil is released during the test, this will not be an indication that oil and gas flow from the wellbore has been permanently stopped.”
Information gathered during the test will be reviewed with government agencies, including the federal science team, to determine next steps.
The sealing cap system never before has been deployed at these depths or under these conditions, and its efficiency and ability to contain the oil and gas cannot be assured, BP said. The damaged wellhead lies nearly a mile beneath the surface about 40 miles southeast of Louisiana’s Mississippi Delta.
BP is drilling two relief wells that the company says “remain the sole means to permanently seal and isolate the well.”
During the well integrity test, operations on the first relief well have been temporarily stopped while the well was at 17,840 ft as a precaution, the company said. Operations on the second relief well have been temporarily suspended at 15,874 feet to ensure that there is no interference with the first relief well.
Admiral Allen said, “We’re encouraged by this development, but this isn’t over. Over the next several hours we will continue to collect data and work with the federal science team to analyze this information and perform additional seismic mapping runs in the hopes of gaining a better understanding on the condition of the well bore and options for temporary shut in of the well during a hurricane.”
He said, “It remains likely that we will return to the containment process using this new stacking cap connected to the risers to attempt to collect up to 80,000 barrels of oil per day until the relief well is completed.”
The largest oil spill in U.S. history has poured millions of barrels of oil into the Gulf of Mexico, fouling at least 550 miles of coastline in four states and closing one-third of the gulf to fishing.