An appraisal well operated by Eni was drilled on the Hewett field, in the Southern North Sea, for the Bacton CCS project. It is the first carbon storage appraisal well to be drilled on acreage licensed by the North Sea Transition Authority (NSTA) as part of the world’s first large-scale carbon storage licensing round in 2023.
Hewett, 18 mi off the Norfolk coast, was one of the UKCS’s longest serving gas fields. Its original operator, Phillips, started production from the field in 1969, making Hewett only the third North Sea field to reach this stage, after West Sole and Leman. The field had produced 3.5 trillion cu ft of gas by the time it permanently shut down in 2023.
Now Eni wants to give Hewett a new lease of life as a carbon store, underpinning its Bacton CCS project. It is thought to be capable of storing up to 10 million tons of CO₂ per year emitted from the Bacton and wider Thames Estuary area, as well as potentially offering decarbonization solutions for emitters across the European Union.
Eni contracted the Valaris 72 jackup to drill the well, and work got under way in May 2025. Extensive data sampling was conducted, including cutting 270 ft of core and performing a nitrogen injection test, before plugging and abandoning it.
The data collected will inform the development plans for the Bacton CCS project by enabling the operator to build a fuller picture of the reservoir’s post-production characteristics and conditions, including reservoir pressures, possible injection rates, wellbore integrity and leakage risk.
