The dawning of Australia’s decommissioning sector

A complicated history

Previously moored between the Laminaria and Corallina oil fields, 550km Northwest of Darwin, the Northern Endeavour was originally installed in the mid-1990s and once processed 170,000 barrels of oil a day. In 2019 a regulatory inspection found it to be in degraded state and insisted it was shut down, citing an immediate threat to health and safety. With the private operator falling into liquidation, the Commonwealth took responsibility for the Northern Endeavour facility and engaged Petrofac as its partner through a global procurement exercise to deliver FPSO disconnection and decommissioning outcomes. 

Integrating services to deliver safely and efficiently

Our Australian team, based in Perth, took operational control of the Northern Endeavour FPSO on behalf of the Commonwealth in October 2022. We were contracted to complete phase one of decommissioning and were responsible for the safety and day-to-day operation of the FPSO, as well as preparing it for disconnection from its subsea equipment and the temporary suspension of the wells. This included flushing and cleaning the topsides and sub-sea pipelines and sea-fastening to prepare for tow.

This is a high-profile, landmark project for Australia’s offshore oil and gas sector, and we are leading the way by integrating our capabilities and experience to:

• Upskill the local workforce, generating jobs, local skills and nurturing the local supply chain.
• Integrate our in-house capabilities to manage the day-to-day operatorship and prepare for well and asset decommissioning phases.
• Draw on our experience in mature and highly regulated regions, such as the United Kingdom Continental Shelf (UKCS) to ensure the safe and cost-efficient preparation of the FPSO for removal.
• In the context of the decommissioning safety case, maintaining close collaboration with the National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) to secure regulatory consent for each step leading up to FPSO disconnection.

Key facts / project highlights

• First outsourced operator to hold an accepted decommissioning safety case
• Six-month successful transition of operatorship to Petrofac
• 274- metre-long FPSO facility
• Nine subsea oil wells to be suspended
• 400-metres deep wells 

Global experience, local delivery

Exporting our decommissioning expertise from the mature and highly regulated UK Continental Shelf (UKCS) to the region has been pivotal in creating local jobs and opportunities for upskilling the Australian workforce and local supply chain in decommissioning.

When we were first awarded the decommissioning project, a commitment to community and economic benefits such as employment, training and local business opportunities was considered as important as the technical scope.

Learn more about how we are maximising local value beyond shutdown.

Overcoming unique project challenges

This was a uniquely challenging project. For example, a major hull cleaning campaign was necessary – arguably one of the most challenging in the history of the global oil and gas sector. With the hull never having been cleaned previously, the volume of marine growth had grown to a depth of some 40-60cm across the entire 10,000-square metre surface of the hull. This meant that the conventional approach, using a remotely operated vehicle (ROV), wouldn’t be feasible. Instead, we had to work with our sub-contractor, Bhagwan Marine, headquartered in Western Australia, to devise a bespoke process involving a team of divers wielding high-pressure water jets. The dive team cleared nearly 9,000 square meters of marine growth from the FPSO’s hull. That’s the equivalent of over 34 tennis courts worth of marine growth removed. To add to the hazards faced in the removal of this unprecedented quantity of marine growth, the team also had to contend with a risk of swordfish attacks.

End of an era

For many people on our Northern Endeavour decommissioning team, the departure of the vessel from the oilfields it called home for 26 years was a bittersweet moment.

Two of our senior team members, back-to-back Offshore Installation Managers Brendan White and Mark Parry, had both worked on the original construction and commissioning of the vessel and spent much of their subsequent careers on board. “Obviously, it’s a time of mixed emotions,” says Brendan, “My history with the vessel dates back 25 years, and it’s been central to my working life for the past five years. So, yes, of course, I’m sorry to see her go. But it’s satisfying to have seen the project through. It’s been an incredible experience with an incredible bunch of people, and a project that really builds Petrofac’s decommissioning credentials.”

Achieving major milestones in decommissioning safety

We received first and second decommissioning safety case acceptances from Australia’s regulator, NOPSEMA, two months ahead of schedule. Early and continuous engagement with NOPSEMA, sharing knowledge on our operating methods in other geographies, presenting safety case strategies to obtain an early buy-in and implementing feedback made this achievement possible.

The milestone safety case permits us to commence decommissioning and disconnection of the Northern Endeavour FPSO vessel which has maintained a non-production ‘lighthouse’ mode during preparations for decommissioning.

We continue to work closely with the Commonwealth and our supply chain to deliver on this landmark project.