OGUK Decom Insight Report 2021

CASE STUDY: Netherlands – Wintershall

Wintershall in the Southern North Sea since 1965, has substantial experience in decommissioning and re-using its installations. Since the late 1980s, it has decommissioned 58 wells and removed 16 production platforms, of which seven topsides were reused at new locations in the Southern North Sea. Decommissioning and complete removal of its assets is part of the company’s activity cycle. The company is also a strong believer in co-operation between the producers and it shares the lessons it has learned within the Nexstep organisation. Wintershall Noordzee is also participating in the Nexstep Joint Campaign on Mudline Suspended (MLS) wells. Thewell decommissioning process in the current campaign has a relative Noordzee, active

Wintershall’s Dutch campaign gets under way InAugust 2021,Wintershall NoordzeeBV– a 50-50 joint venture between Wintershall Dea AG and Gazprom EP International BV – embarked on a large-scale, cross-border decommissioning programme in the Southern North Sea. This campaign, for its platform-based wells, demonstrates the company’s commitment to decommissioning. The first part of Wintershall Noordzee’s programme will last for about one and a half years and entails the decommissioning of 24 wells in both Dutch and German waters and the removal of two platforms and two subsea installations. The tender for this extensive program was granted to the Dutch contractor Swift Drilling. The Swift-10 jack-up rig has been modified and prepared to start work after a period of stacking arising from the worldwide economic slump in offshore activities. The campaign began at the P9 location, where two subsea wells were decommissioned. After successful finalisation by mid-October, the seabed domes were removed by a vessel. The next stop for the rig is the Q4-A location, where decommissioning work needs to be completed to make way for a wind farm. The Q4-A and Q4-B platforms stand where the Hollandse Kust Noord wind farm is to be built. Removal of the two production platforms is foreseen for mid-2022.

low complexity and will be executed with a vessel rather than a rig. Aswellasitsplatformbasedwells,thecontractthatWintershallNoordzee has for the Swift-10 includes options to extend the campaign beyond the current 24 well scope. In parallel to the well decommissioning scope, the company is also preparing for removal of related installations.

DECOMMISSIONING INSIGHT 2021

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