DeepOcean retrieves wellhead protection structure from Seven Seas field

DeepOcean completed the recovery of a subsea wellhead protection structure at Spirit Energy’s Seven Seas field and the disconnection of subsea infrastructure at the operator’s nearby Grove West field in the southern North Sea. Both scopes were carried out using proprietary in-house tooling ahead of a planned rig campaign at the two fields.

DeepOcean provided onshore engineering and project management for the work, deploying the construction vessel Edda Freya to retrieve the wellhead protection structure, which weighed more than 100 tonnes, along with associated subsea infrastructure. The structure had served the Seven Seas field since 2011. Its supporting piles were cut three meters below the seabed before retrieval. All recovered materials were transported for reuse, recycling or disposal. The project was managed and executed by DeepOcean’s Aberdeen-based operations.

At Grove West, DeepOcean disconnected a spool from a subsea Christmas tree and two subsea flanges, using a remotely operated vehicle combined with specialized tooling in place of diver intervention. The methodologies and tooling were developed during the Gryphon Alpha FPSO removal project last year. The Seven Seas structure was located approximately 80 km offshore the East Yorkshire coast in a water depth of around 33 meters, while the Grove West structure was located approximately 130 km east of the UK coastline in a water depth of around 40 meters.