Offshore oil and gas decommissioning has gained significant momentum in recent years, particularly in regions like Western Australia and the US Gulf of Mexico, where aging infrastructure, environmental considerations, and tightening regulations have spurred the industry to take decisive action.
On 31 May, two industry leaders—one a major independent Australian E&P and the other a US-based offshore services provider—announced the award of multiple contracts for decommissioning work in their respective areas.
Australia
Woodside Energy said it has awarded all major contracts for the decommissioning of subsea infrastructure at the Enfield, Griffin, Stybarrow, and Echo/Yodel oil and gas fields located offshore Western Australia.
The Perth-based producer said the completion of the contracts enables the start of the decommissioning campaign in the fourth quarter of 2023. This campaign comes after the successful decommissioning activities underway at the Enfield and Balnaves fields since the first quarter of 2022.
The campaign will involve the decommissioning of the Nganhurra riser turret mooring (RTM) at the Enfield field, the Griffin RTM, and the Stybarrow disconnectable turret mooring. Woodside added that the work is pending regulatory approvals.
"We are partnering with a range of providers possessing specialist capabilities and experience to ensure the safe and successful execution of one of the largest decommissioning campaigns undertaken offshore Western Australia,” said Michal Abdullah, Woodside Energy’s vice president of projects Australia.
Abdullah added that Woodside is progressing with its planning and remains on track to meet regulatory requirements for completing the campaign. The company also is engaging in extensive stakeholder consultation to develop environmental plans for the campaign, which are either being updated based on stakeholder feedback or submitted to the regulator, NOPSEMA, for assessment.
Woodside noted that among the specialist contractors selected for the campaign are TechnipFMC, Heerema, McDermott, Fugro, DOF, and McMahon. Transocean was awarded a contract for the permanent plug and abandonment of wells in the Stybarrow field.
US Gulf of Mexico
Helix Alliance, a subsidiary of Helix Energy Solutions, said it secured a major contract for the decommissioning of multiple wells, pipelines, and structures in the US Gulf of Mexico shelf from an undisclosed operator.
The Louisiana-based Helix Alliance is set to begin the project in mid-2023, with the scope of work encompassing the plug and abandonment of 39 wells, 15 pipelines, and 7 structures.
"This award demonstrates Helix's position as the preeminent company for full-field decommissioning in the Gulf of Mexico shelf, along with our other services supporting the full life cycle of offshore fields,” said Owen Kratz, Helix’s president and chief executive.
He added that the company's acquisition of Alliance last year has further expanded its industry-leading decommissioning services.
To execute these tasks, the company plans to deploy a range of assets, including the EPIC Hedron heavy-lift derrick barge for structure removals, lifeboats for plug and abandonment activities, the Triton Explorer dive support vessel for pipeline abandonments, and several other Helix Alliance offshore support vessels.
Equipped with a 1,763-ton capacity, a fully revolving crane, and accommodations for 300 personnel, the EPIC Hedron has capabilities for heavy-lift, decommissioning, construction, and installation projects.
