Offshore oil and gas operators in the Gulf of Mexico are continuing to evacuate platforms and rigs in preparation for Tropical Depression No. 9, the Bureau of Safety and Environmental Enforcement's Hurricane Response Team confirmed in a news release Tuesday. The BSEE team will continue to work with offshore operators and other state and federal agencies until operations return to normal and the storm is no longer a threat to Gulf of Mexico oil and gas activities.
Based on data from offshore operator reports submitted as of 11:30 a.m. Tuesday, personnel have been evacuated from a total of nine production platforms representing 1.20 percent of the 750 manned platforms in the Gulf. Production platforms are the structures located offshore from which oil and natural gas are produced. Unlike drilling rigs, which typically move from location to location, production facilities remain in the same location throughout a project’s duration.
Personnel have been evacuated from one non-dynamically positioned rig, representing 9.1 percent of the 11 rigs of this type currently operating in the Gulf. Rigs can include several types of offshore drilling facilities including jackup rigs, platform rigs, all submersibles and moored semisubmersibles. Seven dynamically positioned rigs have moved off location out of the storm’s path as a precaution, a number that represents 37 percent of the 19 DP rigs currently operating in the Gulf.
DP rigs maintain their location while conducting well operations by using thrusters and propellers; the rigs are not moored to the seafloor and can therefore move off location in a relatively short time frame. Personnel remain on-board and return to the location once the storm has passed.
According to the release:
As part of the evacuation process, personnel activate the applicable shut-in procedure, which can frequently be accomplished from a remote location. This involves closing the sub-surface safety valves located below the surface of the ocean floor to prevent the release of oil or gas. During previous hurricane seasons, the shut-in valves functioned 100 percent of the time, efficiently shutting in production from wells on the Outer Continental Shelf and protecting the marine and coastal environments. Shutting-in oil and gas production is a standard procedure conducted by industry for safety and environmental reasons.
From operator reports, it is estimated that approximately 22.06 percent of the current oil production in the Gulf of Mexico has been shut-in. It is also estimated that approximately 10.18 percent of the natural gas production in the Gulf of Mexico has been shut-in. The production percentages are calculated using information submitted by offshore operators in daily reports. Shut-in production information included in these reports is based on the amount of oil and gas the operator expected to produce that day. The shut-in production figures therefore are estimates, which BSEE compares to historical production reports to ensure the estimates follow a logical pattern.
After 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.