UK-based oil and gas company EnQuest has said it has started cessation of production activities on the Northern Producer floating production facility at the Don fields in the North Sea.
"The process, which began on Monday 1 March, is expected to take several days to complete, with initial decommissioning activities already underway," EnQuest said earlier this week.
EnQuest has a majority share interest in the Don fields with co-venturer Ithaca Energy and has been the operator of the fields since 2009 through its predecessor company Petrofac Energy Developments Limited (‘PEDL’).
All four fields are tied back to the Northern Producer which is planned to come off-station in April 2021.
The decommissioning plans entail the removal of the Northern Producer Floating Production Facility, and the removal of the related riser systems from the Don South West, and West Don fields in the North Sea.
The Northern Producer platform is an AKER H3 semi-submersible unit originally constructed by Trosvik Framnaes in Norway in 1976. In 1996 the vessel was purchased by Northern Offshore Ltd, Norway, and renamed the Northern Producer.
Since May 2009, the Northern Producer has provided the export route for the Don South West, Conrie Ythan, and West Don fields, located in the Northern North Sea sector of the UK Continental Shelf and operated by EnQuest.
These fields are located approximately 527km north-north-east of Aberdeen in water depths between ~165m and ~178m.
The Northern Producer is operated by EnQuest Heather Limited as the duty holder but owned by Qualimar Shipping Company Limited.
The decommissioning plan includes the Northern Producer unit being used for initial decommissioning activities such as flushing or de-oiling of the subsea infrastructure and to support the implementation of positive isolations for the wells. Once these activities have been completed the vessel will depart the field. The anchors and anchor chains will be fully recovered.
The FPF will be taken off station with the assistance of anchor handling vessels (AHV) and an ROV Support Vessel (ROVSV). The activities to disconnect or sever and recover the risers, severed pipelines and associated structures, and protection and stabilization features will be completed using a ROVSV, Construction Support Vessel (CSV) or Multi Support Vessel (MSV).
All the flexible risers and pipelines associated with the Don South West and West Don infrastructure will be cleaned and flushed, with the risers and surface laid sections of the pipelines in and around the 500m safety zone being fully removed. This will remove potential snagging hazards from the area.
On departure, the owners of the offshore platform will pursue alternative arrangements for the redeployment of the FPF. In case no further employment is secured, the vessel will be taken to shore, dismantled, and recycled.