DeepOcean has completed subsea decommissioning work at Spirit Energy‘s Seven Seas and Grove West fields in the southern UK North Sea, including recovery of a wellhead protection structure and disconnection of subsea infrastructure using proprietary tooling developed in-house.
The work forms part of Spirit Energy’s broader decommissioning program for the two fields and was completed in preparation for a planned rig campaign.
DeepOcean provided engineering, project management and offshore execution for the project, deploying the construction vessel Edda Freya to recover the remaining wellhead protection structure at the Seven Seas field. The structure, which weighed more than 100 metric tons, had been in service since 2011. The company said all recovered materials will be reused, recycled or responsibly disposed of.
“The wellhead protection structure at Seven Seas has served the field since 2011 and remains in very good shape,” said Robin Mawhinney, executive vice president for DeepOcean’s Europe, Middle East and Africa region. “We were delighted to support Spirit Energy on this project and look forward to working with Spirit Energy on future scopes of work.”
At the nearby Grove West field, DeepOcean disconnected a spool from a subsea Christmas tree using a remotely operated vehicle (ROV) and specialized tooling, eliminating the need for traditional diver intervention.
The company said the operation utilized methodologies and proprietary tooling originally developed during the Gryphon Alpha FPSO removal project completed last year, further expanding its subsea decommissioning capabilities.
Spirit Energy said the work supports its objective of maximizing material recovery while reducing waste throughout its decommissioning program.
“By working closely with specialist contractors such as DeepOcean and leveraging the UK supply chain, we have safely recycled more than 95% of materials from decommissioned assets and infrastructure,” said Ceri Wheaton, decommissioning manager at Spirit Energy.
The Seven Seas field is located about 80 km off the East Yorkshire coast in approximately 33 m of water, while Grove West lies about 130 km offshore in roughly 40 m of water.