Factbox: Oil spill commission findings

WASHINGTON (Reuters) - The White House’s oil spill commission presented preliminary findings on Monday on the events and decisions that led to the April 20 Deepwater Horizon blowout in the Gulf of Mexico.

Following are the commission’s preliminary conclusions regarding potential technical problems that contributed to the explosion:

-Hydrocarbon flow path was exclusively through shoe track and up through casing

-Cement (potentially contaminated or displaced by other materials) in shoe track and in some portion of annular space failed to isolate hydrocarbons

-Pre-job laboratory data should have prompted redesign of cement slurry

-Cement evaluation tools might have identified cementing failure, but most operators would not have run tools at that time. They would have relied on the negative pressure test

-Negative pressure test repeatedly showed the primary cement job had not isolated hydrocarbons

-Despite those results, BP and TO personnel treated negative pressure test as a complete success

-BP’s temporary abandonment procedures introduced additional risk

-Number of simultaneous activities and nature of flow monitoring equipment made kick detection more difficult during riser displacement

-Nevertheless, kick indications were clear enough that if observed would have allowed the rig crew to have responded earlier

-Once the rig crew recognized the influx, there were several options that might have prevented or delayed the explosion and/or shut in the well

-Diverting overboard might have prevented or delayed the explosion. Triggering the EDS prior to the explosion might have shut in the well and limited the impact of any explosion and/or the blowout

-Technical conclusions regarding BOP should await results of forensic BOP examination and testing

-No evidence at this time to suggest there was a conscious decision to sacrifice safety concerns to save money.

Reporting by Emily Stephenson and Ayesha Rascoe; editing by Sofina Mirza-Reid