Oil company Perenco UK says it will start to close down operations at Wytch Farm near Corfe Castle in Dorset from the end of 2027 as oil reserves begin to run dry.
Almost a year on from the oil spill at the nearby Arne peninsula which deposited 200 barrels of an oil and water mix into Poole Harbour, plans are being made for the phased closure of production at the controversial oil farm, with potentially all operations shut down by 2037.
Wytch Farm is well hidden within a forested area, but much will be restored to heathland
One of the gathering stations at Perenco’s Wytch Farm site near Corfe Castle
Plans being made to restore the heathland
Perenco, a major Purbeck employer, says it will shut the first of the oil wells at Wytch Farm, by the end of 2027.
Output is already down 90 percent from a high two decades ago. In 1999 the largest onshore oilfield in western Europe was producing 100,000 barrels a day but by 2024 that has fallen to just 9,000 to 10,000 barrels a day.
The access road to Wytch Farm will also be decommissioned, although it may form part of a new public cycle route as the area is restored to heathland. Perenco has already begun work towards this long term aim by felling the non native trees in the area.
Extinction Rebellion held protests against Perenco at Poole Harbour and Wytch Farm in 2023
Leak caused by microbial corrosion
Although the cause and effect of the oil spill from Wytch Farm in March 2023 is still under consideration by the Environment Agency, the oil company says it was caused by microbial corrosion in a buried pipeline, which was more aggressive than expected and which wasn’t present during a 2022 inline inspection.
Perenco says that the process conditions have since been changed to prevent future microbial corrosion and the frequency of inspections, using robotic monitors, has now increased.
Environmental activists have been calling for action against Perenco and the closure of Wytch Farm since the oil spill, and a government minister has said that the company will be held responsible for paying for the damage caused.
Booms put up at the mouth of Ower Bay have now been removed
Ower Bay is ‘no longer contaminated’
An estimated 200 barrels of reservoir fluid, a mixture of 85 percent water and 15 percent oil, leaked from an underground pipeline from Wytch Farm into Ower Bay, which is part of Poole Harbour, an area of international importance for wildlife conservation.
A major incident was declared and an emergency response to contain the hazardous leak was coordinated by Poole Harbour Commissioners.
Booms were put in place across Ower Bay to prevent any further spread of the oil into Poole Harbour, an ecologically sensitive area that shares a shoreline with RSPB Arne nature reserve and the National Trust owned Studland peninsula and Brownsea Island.
At the time, there were serious concerns from RSPB Arne, the National Trust and Dorset Wildlife Trust about the effects of the spill on wading birds and marine life in the harbour and surrounding area.
But although the site around Ower Bay and the wider Poole Harbour will be monitored for another two years, the Local Resilience Forum says that the area is no longer contaminated and the booms have been removed.
Poole Harbour Commissioners led an immediate response to news of the oil spill in March 2023
Area ‘looks like it did before the spill’
A spokesperson for the Local Resilence Forum – which includes members from Dorset Council, the Environment Agency, police, fire and ambulance services and the NHS – said:
“I can confirm that the booms have now been removed from Ower Bay and the area looks much like it did on 25th March 2023, the day before the spill occurred.
“Due to the quick action of all partners, there have been no reports of oil outside of the contaminated area in Ower Bay since Wednesday 5th April 2023.
“Since this time, focused localised clean-up at the release site and coordinated monitoring and assessment of the immediate environment and Poole Harbour has been carried out.”
Despite early sightings of oil stained birds in 2023, the impact on wildlife seems to have been minimal
Further monitoring for two more years
The Local Resilence Forum spokesperson added:
“Investigation and monitoring work performed during 2023 identified impacts on the saltmarsh and reed habitat within a limited area of the southern creek in Ower Bay.
“Remediation works continued, subject to tidal conditions, until early January 2024. During these works every effort was taken to limit impact on the features of the area and all necessary wildlife surveys were conducted before works took place to limit impacts on local species.
“Following completion of this remediation activity there has been a programme of sediment and surface water monitoring analysis.
“This has confirmed that the remediation activity has been successful and there is no longer contamination in the southern creek area of Ower Bay that presents a risk to the wider Poole Harbour.
“Further monitoring of the site during 2024 and 2025 will be ongoing to assess the recovery of the site.”
Carbon capture sees liquid carbon dioxide safely locked away underground
Perenco plans carbon capture stores
Perenco is now looking at the viability of using underground reservoirs at Wytch Farm from which oil has been extracted for storing liquid carbon dioxide collected by a carbon capture programme.
It already has two carbon capture schemes underway off the east coast of England, the Poseidon and the Orion projects, which it says are cutting edge schemes to decarbonise England and capable of creating new, highly skilled jobs.
Carbon capture takes carbon dioxide produced from burning fossil fuels, or as a by-product of industrial manufacturing processes, which is then compressed and stored within deep underground rock formations like the depleted oil reservoirs at Arne.
The process prevents carbon dioxide from entering the atmosphere and contributing to climate change.
Decommissioning could see non native pine trees felled, heathland restored and public cycle ways established
The costs of decommissioning buildings and infrastructure at the Wytch Farm are likely to be huge
Decommission costs may hit £150 million
The same forces that hold oil and gas within the Earth’s crust for millions of years can trap the captured carbon permanently, or until other industries can make use of it, for example in the production of synthetic hydrocarbon fuels.
Oil has been produced at Wytch Farm since 1979, originally by the government owned British Gas Corporation before BP took over in 1984 and subsequently sold out to Perenco in 2011. The original end date for the oil fields had been set at 2016.
There are three separate reservoirs known as Bridport, Sherwood and Frome, from 3,000 feet to 5,200 feet below Poole Harbour and Poole Bay, with around a dozen onshore wellheads.
Final decommissioning of the oil field once it reaches the end of its life has been estimated at a cost of £150 million.
