Eni seeks approval for decom ops offshore Australia

Eni Energy Bonaparte, an affiliate of Italy’s energy titan Eni, has submitted a revised environment plan for decommissioning operations at a field in the Bonaparte Basin in northern Western Australia to the Australian Commonwealth regulator, National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA).

Petrel – the field in question – is located in permits NT/RL1 and WA-6-R. The closest wellhead to the shore is Petrel-3, located in water depths of approximately 95 meters. Together with Petrel-4, the well has been suspended since the 1980s, with wellheads remaining in situ within the NT/RL1 permit. 

According to NOPSEMA, the wells were suspended under the regulations at the time with barriers across and above the reservoir including the testing of the barriers. The reservoir is isolated in both wells and will not flow in their current condition.

Eni has presented several activities as part of the Petrel-3 and Petrel-4 monitoring and decommissioning environment plan to ensure that the condition of the seabed equipment on the wells remains unchanged and plan for the decommissioning campaign.

The Italian major has proposed annual general visual inspections (GVI) as part of the in-force well operations management plan (WOMP) until both wells are permanently plugged and abandoned. The inspections will be performed within the five-year WOMP period using a remotely operated vehicle (ROV) from its contracted fleet. Marine growth may be removed from wellhead equipment to expedite the inspection and prepare for decommissioning.

The plan also includes geophysical and geotechnical survey campaigns, as well as a re-decommissioning vessel campaign to prepare the wells for operations. High-pressure cleaning will be deployed to allow detailed inspection and preparation. Other activities on the agenda entail the removal of the corrosion caps, wellhead 3D scan by camera or laser to ensure integrity, and corrosion cap replacement.

The decommissioning campaign also encompasses partial, complete, and leave-in-situ removal options. As for post-decommissioning, an as-left survey is planned to be carried out to ensure all infrastructure is removed as per scope.

The planned timeline for these activities is 2025–2027 to allow time for wellhead integrity investigations, site-specific surveys, vessel and rig feasibility checks, vessel and rig availability and scheduling, weather conditions, and consideration of neap tides and seasonal met ocean operability.

The oil and gas giant recently filed an official strategic lawsuit against public participation (SLAPP) against Greenpeace Italy and ReCommon, joining the likes of Shell, TotalEnergies, and Energy Transfer in what the NGOs see as an ill-founded legal assault and an attack against civil freedoms and environmental protection. 

Despite pushback from NGOs, Eni remains adamant that fossil fuels are here to stay. According to the latest edition of its global energy statistical review, the World Energy Review (WER), fossil fuels made up 80% of energy demand worldwide in 2023, while solar PV and wind accounted for only 3%.