Heerema Marine Contractors crane-lift barge Thialf has removed the decommissioned Schooner gas field wellhead platform from the UK southern North Sea for operator DNO.
Courtesy Heerema Marine Contractors
Thialf is capable of a tandem lift of 14,200 metric tons.
Offshore staff
OSLO, Norway — Heerema Marine Contractors crane-lift barge Thialf has removed the decommissioned Schooner gas field wellhead platform from the UK southern North Sea for operator DNO.
Courtesy DNO
Schooner decommissioning program in the southern North Sea
The vessel lifted onboard the 1,200-metric ton platform deck on May 17 and removed the jacket six days later after the piles had been severed 3 m below the seabed. Deck and jacket have since arrived at the Hoondert Yard in the Netherlands for dismantlement and recycling.
In 2019 DNO assumed operatorship in the Schooner and Ketch fields in the UK and the Oselvar subsea field in the Norwegian North Sea, the previous operator having deferred the decommissioning.
The company completed P&A of the nine Ketch and three Oselvar wells in 2021, followed by the 12 Schooner wells in 2022. Both the Ketch and Oselvar production facilities were removed and dismantled last year, with about 95% of the recovered materials set to be recycled.
DNO’s COO Chris Spencer said, “We have conducted these operations in a safe, cost-efficient and environmentally responsible manner, coordinating five tier-one contractors and displaying our capabilities as a full life-cycle offshore operator.”
