Woodside Energy has released an update of the company's decommissioning activities for the fourth quarter of 2024.
The removal of the Griffin Riser Turret Mooring (RTM) has been a highlight for the company as it marked the removal of nearly 25000 tonnes of infrastructure that included over 200 kms of pipe and 100 subsea structures that covered the Enfield, Echo Yodel, Stybarrow and Griffin fields. RTM removal besides, 20 wells have also been permanently plugged.
The RTM was recovered without significant obstacles to be transported to the Australian Marine Complex at Henderson, Western Australia, where its components will be cleaned and disassembled for recycling or reuse.
The Griffin field that is situated off 65 km north west of Onslow and 94 km north east of Exmouth had served in its lifetime Western Australia’s power needs with not only 62 billion cubic feet of gas, but also 167 million barrels of oil.
McDermott's EPR contract in Stybarrow
Woodside's decommissioning campaigns at Stybarrow included the plugging and abandoning of three wells, removal of several moorings, structures, and wellheads that covered multiple fields offshore Western Australia. Last year, the company plugged and abandoned seven of 10 Stybarrow wells, recovered more than 90 subsea structures including wellheads, Xmas trees
and manifolds, and recovered 149 km of pipe.
Woodside's decommissioning work in Stybarrow was supported by McDermott under an engineering, procurement and removal contract.
“This award not only demonstrates McDermott’s proven track record in undertaking deepwater projects of diverse scopes, but it also highlights the critical importance of decommissioning in the offshore industry.
“With our seamless integration of engineering, fabrication, and offshore mobilisation expertise, we believe we are well-equipped to execute this project efficiently and responsibly, ensuring the safe recovery and removal of the Stybarrow DTM buoy,” said Mahesh Swaminathan, Senior Vice President, Subsea and Floating Facilities, McDermott.
The contract enables McDermott to fully remove the Stybarrow disconnectable turret mooring (DTM) buoy, and provide project management and engineering services for the recovery, transportation and offloading of the DTM buoy to an onshore yard for dismantling and disposal.
Allseas' role in Bass Strait
The Bass Strait decommissioning work continues as well, with plug and abandonment completed on the Perch and Dolphin facilities. Steel gravity based monotowers, the Perch and Dolphin facilities saw the deployment of DOF multi-purpose support vessel (MPSV) Skandi Darwin.
The MPSV's floating support asset can accomodate the whole workforce, eliminating crew transportaion costs. It also allows to complete abandonment operations on non-producing facilities which do not have accommodation based on them.
Speaking of the MSVP, Marine Field Superintendent, Matt Barney said, “We’re excited to start utilising the MPSV to expand our capabilities and adopt new technology to identify efficiencies, while ensuring the work can be completed safely.”
Allseas is also part of the Bass Strait decommissioning campaign, whereby the company will be dismantling up to 12 retired platforms from the region. “This landmark decommissioning project represents a significant milestone for Allseas in Australia,” said Evert van Herel, General Manager of Allseas Australia.
To know more about Australia's decommissioning scene, click here.
