Decommissioning completed on South Angsi Alpha platform off Malaysia

Netherlands-based Marine Masters, through Marine Masters Malaysia, has successfully completed its offshore scope for the decommissioning of the South Angsi Alpha (SAA) platform operated by Hibiscus Oil and Gas Malaysia.

Marine Masters said the campaign entails the repurposing of retired offshore infrastructure, with the platform’s substructure now resting on the seabed as part of a rig-to-reef project in Malaysian waters.

The SAA platform, located 130 kilometres off the coast of Terengganu, was a 4,000-tonne, four-legged mobile offshore application barge (MOAB) that served as a full production facility for over 15 years.

Following cessation of production, the topside and substructure were prepared for safe removal and partial reefing in line with Malaysian regulatory approvals. Marine Masters said this marks the largest platform ever to be decommissioned and repurposed within Malaysian waters.

Marine Masters was overall responsible for the removal of the MOAB by making use of the reversed installation method and the removal of various associated components for safe onshore disposal.

The jacket was cut at -55 metres LAT and vertically separated, allowing the sections to be laid on the seabed as artificial reef structures. Additional tasks included the recovery of all 13 conductors, the retrieval of four MOAB support legs, and the cutting and transport of the wellhead access platform.

For this reason, multiple techniques were used and special procedures developed to perform remotely operated underwater cutting (assisted by ROVs), high speed PVL hand cutting (by divers), set up efficient personnel transfer between the work barge and the MOAB up to custom-designed lifting systems to avoid the use of expensive heavy lift vessels.

The MOAB topside has now been successfully skidded to shore at Labuan Shipyard, and all loose items have been offloaded. The accommodation work barge was demobilised at the same time, while the two transport barges are currently en route to their respective demobilisation ports.

Marine Masters said that although the offshore scope is complete, the project continues with the final handling and disposal of the topside components.