Program Overview
The Stybarrow Plug & Abandonment Disposals Project involved the safe and environmentally responsible handling of decommissioned offshore infrastructure from the Stybarrow Field. Birdon managed the receipt, testing, decontamination, and disposal of Oil Country Tubular Goods (OCTGs) and Subsea Christmas Trees (XTs) across multiple work elements.
Materials were received in batches between May 2024 and April 2025, including approximately 2,070 tubulars and completion structures (totalling 1,260 tonnes) at Woodside King Bay Supply Base, as well as three Subsea Christmas Trees (170 tonnes) at Toll Dampier Supply Base.
Birdon’s scope included onshore verification testing, hazardous material management, decontamination, material segregation, and sustainable disposal pathways across multiple specialist facilities.
Quick Facts
- Client
Woodside Energy
- Location
King Bay Supply Base & Toll Dampier Supply Base, WA
- Lifecycle Stage
Decommission
- Timeline
May 2024 – July 2025
- Assets
OCTGs (2,070 tubulars, 1,260 tonnes) and 3 Subsea Christmas Trees (170 tonnes)
Objectives
- Safely manage the disposal of decommissioned offshore infrastructure
- Maximise reuse and recycling of materials
- Ensure compliance with environmental and radiation safety standards
Challenges
- Handling and testing materials potentially contaminated with NORM, mercury, and iron sulphide
- Coordinating logistics across multiple subcontractors and specialist facilities
- Managing safe transport, handling, and processing of heavy and hazardous components
Birdon’s Approach
Birdon delivered the project across two primary work elements, combining structured logistics coordination with specialist decontamination and disposal processes.
For OCTGs (Work Elements 2 & 3), Birdon received and sorted 2,070 tubulars and completion structures, supported by offshore hazard assessments and onshore verification testing by Licensed Radiation Safety Officers and specialist contractors. Tubulars verified as non-contaminated underwent high-pressure pipe cleaning, while NORM-contaminated materials were transferred to waste management facilities for controlled decontamination and clearance testing.
For Subsea Christmas Trees (Work Element 5), Birdon managed load-in, laydown, and controlled handling of three XT structures, establishing bunded work areas, exclusion zones, and engineered support systems. Specialist contractors supported high-pressure cleaning, decontamination, and verification testing, while Birdon crews completed downsizing, lifting, and removal of components following de-pressurisation and de-energisation.
Material streams were segregated and directed to appropriate reuse, resale, or recycling pathways, supported by coordinated logistics across multiple facilities and subcontractors.
Outcomes & Impact
Birdon delivered a safe and compliant decommissioning program across all work elements, achieving high levels of material recovery and reuse.
24% of OCTGs were repurposed for piling and fencing applications, 74% were processed through metal recycling facilities, and 3% were managed via hazardous waste disposal methods. Subsea Christmas Tree components achieved a 95% recycling rate, with a further 5% recovered for reuse.
All operations were completed while maintaining full compliance with environmental and radiation safety standards while supporting sustainable material recovery outcomes.
Capabilities in Action
- Radiation safety compliance, testing, and verification (NORM, mercury, iron sulphide)
- High-pressure industrial cleaning and decontamination processes
- Heavy logistics coordination across multiple sites and subcontractors
- Load-in, laydown, and controlled handling of large offshore components
- Sustainable material recovery, reuse, and recycling pathways
- Delivery aligned with environmental and radiation safety management policies
