Perenco UK has completed the plugging and abandonment of the Leman South and Durango subsea wells in the Southern North Sea, recovering their associated subsea infrastructure through a single offshore campaign.
The work covered Leman South well 53/02a-15Y and Durango well 48/21a-4z. Perenco delivered the campaign with decommissioning contractor Petrodec, part of the Dixstone group, using Petrodec’s HAEVA jack-up vessel.
The company said operations were completed safely and within the agreed timeframe. It did not disclose the campaign’s cost, duration or the quantity of infrastructure recovered.
The project combined well abandonment and infrastructure removal within one campaign framework. Perenco said this approach reduced reliance on separate offshore projects and high-cost drilling rigs, although it did not publish a cost comparison.
HAEVA campaign builds on earlier abandonment work
The Leman South and Durango work followed subsea abandonment campaigns at Gawain, Arthur and Davy, which also used HAEVA.
Perenco said experience from those projects informed the latest operations. The repeat use of the vessel forms part of its approach to delivering technically complex subsea abandonment and infrastructure recovery across multiple assets.
Jo White, managing director of Perenco UK’s Southern North Sea business, said: “The Leman South and Durango campaigns were not routine P&A projects.”
White described the work as demonstrating a repeatable approach to subsea well abandonment, with HAEVA providing the centre of a combined campaign rather than treating each asset as a standalone offshore project.
The announcement did not provide a breakdown of the technical challenges encountered at either well or explain which operations required different methods from the earlier campaigns.
It also did not identify the specific equipment recovered. The confirmed scope comprises the plugging and abandonment of the two wells and removal of their associated subsea infrastructure.
Combined scope brings well and infrastructure work together
Well plugging and abandonment and subsea infrastructure recovery are separate elements of the decommissioning scope. Perenco’s announcement confirms that both were completed for the two named assets.
The campaign structure brought those activities together under one delivery framework. Perenco presented this as an alternative to relying exclusively on drilling rigs and separately organised offshore projects.
However, the information released does not establish the financial saving achieved or allow a comparison with other vessel and rig combinations. No campaign budget, vessel-day total or benchmark was supplied.
The stated outcome is therefore completion of the work within the agreed schedule, rather than a quantified reduction in decommissioning costs.
The announcement also does not specify the treatment, recycling or disposal routes for the recovered materials, or set out any remaining monitoring obligations.
Decommissioning sits alongside Southern North Sea operations
Perenco has operated in the UK Southern North Sea since 2003. Its regional business includes offshore production infrastructure, subsea wells and pipelines connected to the Bacton and Dimlington terminals.
According to the company, its UK infrastructure comprises 32 offshore installations, 12 subsea wells and more than 2,000km of pipelines. Gas arriving at its terminals is treated, metered and exported into the UK National Grid.
Perenco says it processes almost 15% of UK national gas production. That processing figure is distinct from its own production, which it reports at approximately 50,000 barrels of oil equivalent per day across its UK business.
Around 10,000 barrels per day comes from Wytch Farm, the onshore Dorset oil field where Perenco holds a 95% interest and has operated since 2011.
The Leman South and Durango campaign adds two completed subsea abandonment projects to the company’s Southern North Sea programme. Perenco did not announce the next assets scheduled for a similar campaign or provide a timetable for further work.
