DeepOcean Completes North Sea Subsea Decommissioning for Spirit Energy
DeepOcean completed subsea decommissioning work for Spirit Energy at the Seven Seas and Grove West fields, removing offshore infrastructure and supporting North Sea asset retirement with ROV-based operations.
(P&GJ) — DeepOcean has completed subsea decommissioning work at Spirit Energy's Seven Seas and Grove West fields in the southern North Sea, including removal of a wellhead protection structure and the disconnection of subsea infrastructure.
The project included engineering, project management and offshore execution using the construction vessel Edda Freya. DeepOcean recovered a wellhead protection structure weighing more than 100 metric tons from the Seven Seas field, along with associated subsea infrastructure. The recovered materials were transported for reuse, recycling or disposal.
The work supports Spirit Energy's broader decommissioning program for the two fields and was completed ahead of a planned rig campaign.
DeepOcean also disconnected a spool from a subsea Christmas tree at the Grove West field using a remotely operated vehicle (ROV) and proprietary tooling, eliminating the need for diver intervention.
Robin Mawhinney, executive vice president for DeepOcean's Europe, Middle East and Africa region, said the company successfully removed infrastructure that had served the Seven Seas field since 2011.
"The wellhead protection structure at Seven Seas has served the field since 2011 and remains in very good shape. The piles were cut three metres below the seabed and the subsequent retrieval of the structure was conducted," Mawhinney said.
Spirit Energy said the project aligns with its strategy to maximize material recovery and reduce waste during decommissioning.
"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, Spirit Energy's decommissioning manager.
DeepOcean CEO Øyvind Mikaelsen said the Grove West work built on technology and methodologies developed during the Gryphon Alpha FPSO removal project.
"This project adds to DeepOcean's growing track record of meeting project objectives across subsea decommissioning campaigns," Mikaelsen said.
The Seven Seas field is located about 50 miles (80 km) offshore the East Yorkshire coast in approximately 108 feet (33 meters) of water. Grove West lies about 81 miles (130 km) offshore in water depths of roughly 131 feet (40 meters).