Oil & Gas

Preparations are underway for the largest offshore platform dismantling project in Australia, marking a significant milestone in the country’s oil and gas sector. The operation is being led by Allseas, a specialized energy company based in Washington.

Allseas has been contracted by Esso Australia, a subsidiary of ExxonMobil, to remove 12 decommissioned oil and gas rigs from the Gippsland Bass Basin. The dismantling will involve the removal of up to 12 upper structures and 11 steel jackets, with an estimated total weight of 60,000 tonnes.

Allseas will use its giant heavy-lift vessel, Pioneering Spirit, for this groundbreaking project. This vessel is capable of performing individual lifts of entire offshore structures, including both topsides and jackets, in one operation. The use of Pioneering Spirit will allow the dismantling process to be completed in just a few months, making it one of the largest and most efficient offshore platform decommissioning efforts in history. The operation is scheduled to begin in late 2027 and is expected to be completed within 3 to 4 months.

Once the platforms are removed, the dismantled materials will be transported to Victoria's Barry Beach Marine Terminal, where a separate onshore contractor will handle the recycling and disposal process. Everett van Heurel, Managing Director of Allseas Australia, expressed pride in the historic nature of this project, emphasizing the company's long-standing expertise in subsea piping and construction.

He highlighted that this dismantling will demonstrate the advanced capabilities of Allseas’ individual lift technology in challenging offshore environments like the Bass Strait.

Allseas has already made significant strides in offshore platform removal, including the dismantling of the Brent oil field platforms in the North Sea. This summer, the company completed the removal of the fourth and final platform from the Brent field, an operation described as the heaviest offshore lift ever performed. The removal of these platforms marks the end of an era for the Brent oil field, which has been in operation since 1971.

The project aligns with Allseas’ ongoing efforts to recycle and decommission oil and gas infrastructure, with 98% of materials from previous platform removals already recycled. Additionally, a new partnership between the UK and Australia aims to further enhance collaboration in offshore platform dismantling, combining UK experience with Australia’s growing market for decommissioning services.