Recent global decommissioning experience
In 2020, ExxonMobil concluded two, very different but successful offshore decommissioning campaigns in Canada and the Gulf of Mexico.
Lena platform in the Gulf of Mexico
In July 2020, ExxonMobil created a new reef site in the Gulf of Mexico outer continental shelf when it toppled-in-place the Lena platform jacket, turning it into a deep water reef.
The ExxonMobil team were able to successfully demonstrate to regulators that, as an artificial reef, the Lena will benefit the environment by continuing to provide habitats for rare marine wildlife in the area, which is similar to what we achieved with the Adelaide refinery wharf in South Australia.
We will continue to work closely with regulators as we finalise our decommissioning approach, so that we can achieve similar successful outcomes for the environment in Bass Strait.
Sable field in Canada
In November 2020, ExxonMobil Canada reached a key milestone in the decommissioning of its Sable project with the final removal of all seven offshore platforms which had commenced in May after more than eight years of extensive planning and studies.
ExxonMobil Australia's decommissioning technical team lead, Emma Ogilvie, was the project manager for ExxonMobil’s decommissioning of the Sable project in Canada during the early planning stages.
“At the Sable field, an enormous semi-submersible crane vessel, Heerema’s Thialf, was used to carry out a sequence of separate lifts of platform components, such as topsides and jackets, using a reverse-installation method,” said Emma.
“During this process, an export barge was used to transport five loads of platform components, weighing a total of approximately 48,000 tonnes, across the Atlantic to a disposal and recycling yard in the U.K.”
“Around 99 percent of the material from Sable will be recycled,” she noted.
“Importantly, Sable’s best-in-class safety performance continued throughout the removals campaign, with the project maintaining its lost-time incident free status for more than 19 years.”
Similarly to the work we’re currently taking out in Bass Strait, the Sable platform removal campaign followed multiple years of well plug and abandonment activities, as well as parallel activities to prepare offshore platforms for removal.