SAFETY ALERT NO. 220:

DEEPWATER HORIZON EXPLOSION AND FIRE RESULTING IN MULTIPLE FATALITIES AND RELEASE OF OIL

Country: USA   Location: OFFSHORE : Mobile Drilling Unit

Release Date: 30 April 2010

Type of Activity: Drilling, Workover, Well Services

Function: Drilling

On April 20, 2010, a loss of well control occurred and resulted in an explosion and fire on the Mobile Offshore Drilling Unit Deepwater Horizon. Eleven lives were lost in this incident and the MODU subsequently sank. As of the date of this safety alert the well has not been secured, and the resulting release of oil has been declared a spill of national significance with oil threatening sensitive coastlines and resources in the Gulf of Mexico.

What Went Wrong?:

At the time of the accident, the Deepwater Horizon was operating 52 miles from shore in 4,992 feet of water with a subsea BOP stack. After the Deepwater Horizon sank, ROV’s confirmed that the riser was bent over and still attached to the BOP and that oil is flowing from leaks in the riser above the BOP. Numerous attempts to actuate the BOP have failed.

Corrective actions and Recommendations:

While the exact causes of this event are now under investigation, the tragic nature of this accident compels operators and drilling contractors to inspect their drilling equipment and review their procedures to ensure the safety of personnel and protection of the environment.

Therefore, MMS and the USCG issue the following safety recommendations to operators and drilling contractors:

  1. Examine all well control equipment (both surface and subsea) currently being used to ensure that it has been properly maintained and is capable of shutting in the well during emergency operations. Ensure that the ROV hot-stabs are function-tested and are capable of actuating the BOP.
  2. Review all rig drilling/casing/completion practices to ensure that well control contingencies are not compromised at any point while the BOP is installed on the wellhead.
  3. Review all emergency shutdown and dynamic positioning procedures that interface with emergency well control operations.
  4. Inspect lifesaving and firefighting equipment for compliance with federal requirements.
  5. Ensure that all crew members are familiar with emergency/firefighting equipment, as well as participate in an abandon ship drill. Operators are reminded that the review of emergency equipment and drills should be conducted after each crew change out.
  6. Exercise emergency power equipment to ensure proper operation.
  7. Ensure that all personnel involved in well operations are properly trained and capable of performing their tasks under both normal drilling and emergency well control operations.

Both MMS and the USCG are conducting a joint investigation of the Deepwater Horizon accident. The findings and lessons learned will be documented in a report that will be made public as soon as possible.

Source Contact:

For additional information contact Ms. Melinda Mayes (MMS – 703-787-1063) or Mr. Eric Christensen (USCG – 202-372-1210). For other Safety Alerts issued for OCS oil and gas activities, go to the MMS web site at http://www.mms.gov/safetyalerts/