Following installation of the capping stack and in line with the procedure approved by the National Incident Commander and Unified Area Command, the well integrity test on the MC252 well commenced.
The well integrity test will last at least 6 hours and could last up to 48 hours. During the test, the three ram capping stack is closed, effectively shutting in the well and all sub-sea containment systems (namely, the Q4000 and Helix Producer systems) have been temporarily stopped. Although it cannot be assured, it is expected that no oil will be released to the ocean during the test. 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 the relevant 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.
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. 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. The relief wells remain the sole means to permanently seal and isolate the well.