Woodside Energy Group has awarded all major decommissioning contracts for the subsea infrastructure at the Enfield, Griffin, Stybarrow and Echo Yodelfor oil and gas fields offshore Western Australia.

The contract has been secured by specialist contractors including TechnipFMC, Fugro, DOF, Heerema, McDermott, and McMahon to carry out activities during the subsea decommissioning campaign.

Woodside Energy said that the campaign will include the decommissioning of the Nganhurra riser turret mooring (RTM) on the Enfield field, the Griffin RTM and the Stybarrow disconnectable turret mooring.

Under the terms of the contract, the companies will engage in activities that include the removal and disposal of riser and disconnectable turret moorings, flowlines, umbilicals as well as other subsea infrastructure.

Transocean has won the contract for the permanent plug and abandonment of wells in the Stybarrow oil field.

Woodside Energy Projects Australia vice president Michal Abdullah said: “We are partnering with a range of providers with specialist capabilities and experience to ensure safe and successful execution of one of the largest decommissioning campaigns undertaken offshore Western Australia.

“We are progressing well with our planning and remain on track to meet the regulatory requirements to complete the campaign.

“Woodside is continuing to undertake extensive stakeholder consultation to inform the development of environment plans for the campaign. These plans are either being updated to reflect stakeholder feedback or have been lodged with the regulator, NOPSEMA, for assessment.”

With the finalisation of the contracts, the decommissioning campaign is expected to start in Q4 2023. It is subject to the receipt of regulatory approvals.

The new work comes after the successful decommissioning activities which have been undergoing at the Enfield and Balnaves fields since Q1 2022.