We continue to monitor BP's progress with the Macondo well integrity test, which began July 15. Since then, BP has stopped the flow of oil into the Gulf, but this victory has not been clear-cut. The initial pressure reading of 6,700 pounds per square inch July 16 has increased over the past few days to 6,811 psi. This falls into the inconclusive range between 6,000 psi, which would indicate wellbore damage, and 8,000 psi, indicating an intact wellbore. Furthermore, seismic and sonar monitoring detected leaks near the sealing cap and a seep located 3 kilometres away, but additional testing suggests that the sealing cap leak does not indicate wellbore damage and the seep does not come from the Macondo well.
The US government approved another 24-hour extension to the integrity test Monday, and we expect an update later today. The key question for us is the cause of lower-than-expected pressure readings. While this could be due to reservoir depletion, there is a possibility that oil may have migrated to other layers above the initial reservoir, which would indicate a breach in the wellbore. If wellbore integrity is confirmed, BP will be able to move ahead with relief well drilling for a mid-August completion target. If wellbore integrity is in doubt, more seismic and sonar studies may be needed to locate breaches and make sure the relief well intercepts below any breach.
