Fairfield submits decom plan for Dunlin subsea infrastructure

Fairfield Energy, a late-life asset and decommissioning operator, has submitted its draft decommissioning programs for the Dunlin, Merlin and Osprey field subsea installations and pipelines, in the UK sector of the North Sea, to the UK authorities. 

This is a second company to submit a draft decommissioning plan to the UK’s Department for Business, Energy and Industrial Strategy (BSEI) this week. The first one was Marathon Oil for the Brae Area infrastructure, also in the UK North Sea.

The Greater Dunlin Area is located in UK Block 211/23a and 211/24 of the UKCS, some 500km north-northeast of Aberdeen within the East Shetland Basin, and 11.2km from the boundary line with Norway.

Fairfield became the operator of the Dunlin area in 2008. After establishing it was no longer viable to continue production from the Greater Dunlin Area, the decision to terminate production was announced in June 2015. Cessation of Production (COP) was agreed with the OGA in July that same year. The operator then entered the decommissioning phase.

Back to the current event, Fairfield on Friday submitted its draft plans for the decommissioning of the Dunlin Fuel Gas Import (DFGI) and Dunlin Power Import (DPI) and Osprey and Merlin subsea satellite fields and associated infrastructure.

According to the draft programs, subsea installations will be removed and recovered to shore for recycling/disposal.

This project is part of the overall Greater Dunlin Area decommissioning program.

The infrastructure 

The Dunlin field was discovered by Shell 195 km (121 miles) northeast of Lerwick, Shetland in July 1973. The Dunlin Alpha platform was installed in 1977, comprising a concrete gravity base structure, supporting a steel topsides deck and production facilities. The infrastructure includes Dunlin, Dunlin South West, Osprey and Merlin fields.

Production from the Dunlin A platform started in 1978 and subsea tiebacks, Osprey and Merlin, were developed in 1991 and 1997, respectively. Oil production was exported from Dunlin Alpha via pipeline to the Cormorant A platform, and from there by pipeline to the Sullom Voe oil terminal in the Shetland Islands. During its lifetime, over 522 million barrels of oil have been produced from the Greater Dunlin Area.

The Osprey field facilities comprise two subsea drilling templates and a subsea manifold located some 7km north of Dunlin A. The Merlin field facilities comprise three subsea production wells and a water injection well, located 7km west of Dunlin A.

A 4-inch Dunlin Fuel Gas Import (DFGI) pipeline was installed in 2012, allowing natural gas to be imported from the EnQuest’s Thistle Alpha platform for use as fuel gas for the Dunlin Alpha Water Injection primary movers.

In addition, a 5-inch Dunlin Power Import (DPI) cable runs subsea from the Shell-operated Brent Charlie platform to the Dunlin Alpha platform and was used as a contingency source of power for the Dunlin Alpha platform.

Offshore Energy Today Staff