By Phaedra Friend Troy
Over the weekend, National Incident Commander Admiral Thad Allen recommended moving forward with the planned relief well drilling operations to perform the bottom kill on the Macondo well, issuing orders to BP before the relief well drilling begins again.
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With positive pressure tests obtained on the runaway Macondo well, BP and the team of federal regulators and experts, mulled the possibility of stopping relief well efforts in the deepwaters of the Gulf of Mexico.
“First of all, I want to state up front that our intent and my direction will be to go forward with the relief well and execute the bottom kill,” said Admiral Allen. “Prior to issuing that order, which I have not done to date, I will issue an order this afternoon (Aug. 14, 2010) that will require additional testing, analysis and a higher state of readiness as we move towards the final order which will direct that.”
Preparations Begin for the Bottom Kill
Although pressure tests seemed to prove that the static kill had effectively shut-in the Macondo well, the team has decided to move forward with the bottom kill procedure, following a series of tests and preparations.
“After the results of the Post Cement Pressure Test #3 (Near Ambient Pressure Test), and in response to BP’s request to consider foregoing the Relief Well, the Government Scientific Technical Team has determined that the benefits of the bottom kill procedure outweigh the risks,” Admiral Allen wrote in a directive to Bob Dudley, the chief managing director of BP.
In an effort to determine the best way to lessen risk and perform the bottom kill effectively, Admiral Allen directed BP to develop a pressure relief system, as well as a hydrocarbon containment system to be installed before the Development Driller III intercepts the Macondo well.
Additionally, BP has been asked to remain at the ready to perform relief well drilling when directed by the federal regulators. Also, BP must provide a plan for ambient pressure test and analysis to determine the stability of the well before and after the removal of the Macondo well stack and the BOP replacement.
Finally, BP must be able to prove that the Macondo annulus will not allow hydrocarbon flow in the future – or if the potential is there, under what conditions and with what risk hydrocarbons might flow through the annulus after the BOP stack is removed.
Moving Forward with Relief Well Drilling
An ambient pressure test is scheduled to determine the pressure in the blowout preventer and the capping stack. Additionally, teams are studying the stability of the well, to ensure the proper steps are taken moving forward with the bottom kill.
“In other words, I want BP to tell us their assessment of the stability of the well before and after the removal of the BOP package and before and after the conditions to be created for the bottom kill,” said Admiral Allen. “Once we understand all of that and we make a decision to move forward, I will issue an order for them to actually intercept the well, but that will be a separate order.”
Presently, the Development Driller III drillbit on the first relief well is 3.5 feet away from the Macondo well and about 50 feet above the intercept point on the annulus.
Once the order has been issued to resume relief well drilling, it will take four days or 96 hours to effectively intercept the well.
Bottom kill moves forward, relief well drilling to continue
By Phaedra Friend Troy