Personnel have also been evacuated from 10 rigs, equal to 47.6% of the 21 rigs of this type currently operating in the Gulf. Rigs can include various types of offshore drilling facilities including jackup rigs, platform rigs, all submersibles and moored semisubmersibles.
None of the 20 DP rigs operating in the Gulf of Mexico are off location, as they all returned to pre-storm positioning. DP rigs keep their location while performing well operations by using thrusters and propellers, the rigs are not moored to the seafloor. As a result, they are able to move off location in a short time. Personnel remain on board and return to the location when the storm passes.
Under the evacuation process, personnel shut-in procedures, which, sometimes, can be done remotely. This involves closing the sub-surface safety valves, which is below the surface of the ocean floor to prevent the release of oil or gas. Shutting-in oil and gas production is a standard procedure carried out by industry for safety and environmental purposes.
Based on operator reports, BSEE estimates that around 72.82% of the current oil production in the Gulf of Mexico has been shut-in, equivalent to 1,376,265 barrels of oil per day. It is also estimated that about 61.68% of the natural gas production, or 2,780 million cubic feet per day in the Gulf of Mexico has been shut-in.
Now that the storm has passed, facilities will be inspected. Once all standard checks have been completed, production from undamaged facilities will be brought back on line immediately. Facilities sustaining damage may take longer to bring back on line.
The hurricane passed through oil majors, such as Chevron, BP, BHP, Shell and Anadarko. Thus, the oil majors announced their plans to evacuate or make staffing adjustments on fixed platforms in the affected area.
Specifically, Chevron reported that it halted operations in five of its platforms in the Gulf, while it also evacuated all associated personnel. Similarly, Shell halted productions and evacuated 'non-essential' staff at seven platforms. Additionally, BP Plc and Exxon Mobil Corp. also removed offshore personnel.