CNSOPB Requires Shut-in of Sable Flowline Following Discharge

The Canada-Nova Scotia Offshore Petroleum Board has required ExxonMobil Canada, operator of the Sable Offshore Energy Project, to shut-in the monoethylene glycol (MEG) injection system on the Alma production platform, following a discharge.

The Board received a report on the night of January 12th that ExxonMobil identified a leak of MEG from the undersea pipeline which connects the Alma and Thebaud platforms. This substance, which is a type of industrial anti-freeze, is injected at the Thebaud platform into the 3 inch interfield flowline to prevent the build up of hydrates. Hydrates form as a block of ice within the line, can be very difficult to remove, and pose a potential safety hazard.

The Board is requiring ExxonMobil to complete the shut-in of the MEG injection system on the Alma platform as quickly as safely possible.

Early estimates from ExxonMobil indicated it could take up to 24 hours for the system to be safely shut-in. "Shutting-in" means the flowline will be disconnected from the rest of the Sable infrastructure. Once the shut-in takes place, the MEG flowline can be inspected and repaired.

The Alma platform produces approximately 100 million cubic feet of natural gas per day, which is over a quarter of the total Sable project production. The platform is located approximately 60 kilometers southwest of Sable Island, and the interfield flowline in question is approximately 50 kilometers long.