West Mira rig - Seadrill - Wintershall Dea

Wintershall Dea terminates West Mira rig after x-mas tree incident

Project & Tenders

Offshore drilling contractor Seadrill Limited has revealed that a termination notice has been received for the West Mira rig from Wintershall Dea.

West Mira rig; Credit: Seadrill

The West Mira has had a period of unproductive time following an equipment failure on 19 March 2021. Northern Ocean is the owner of the rig and Seadrill is the operator.

To remind, an incident on the West Mira rig occurred on 19 March during a lifting operation while the rig was working on the Nova field for Wintershall Dea.

While lowering a x-mas tree from the West Mira, the winch wire snapped when the tree was five metres below the sea surface.

As a result, the x-mas tree sunk to the seafloor 368 metres below water level.

No one was injured in the incident, but the drilling operations halted and an investigation was launched.

Northern Ocean previously expected the rig to resume operations by mid-April, subject to weather conditions and other factors which might arise.

In a statement on 26 April, Northern Ocean said the West Mira “continues to remain out of service while work towards agreeing a plan where the rig can return to operations safely is being completed”.

However, this has not happened and Wintershall Dea has now terminated the contract for the rig.

Seadrill said on Wednesday it has been working diligently with Wintershall Dea and the rig’s owner Northern Ocean to prepare the West Mira for a return to work.

Seadrill concluded it will review the notice received and will continue constructive engagement with both Wintershall Dea and Northern Ocean.

Before the incident, the West Mira was working on the Nova field in the North Sea where it was supposed to drill six wells.

The rig started operations on the first well in October 2020. By February 2021, the rig completed the top hole drilling campaign on the Nova field.

The campaign involved drilling some 3,400 metres of top holes for the six Nova production and water injection wells on two different templates.

Under previous plans, the Nova field drilling was expected to last throughout most of 2021, but it is yet unclear if the incident with the rig will change these plans.

When it comes on stream in 2022, Nova will be the fourth subsea field in production for Wintershall Dea.

West Mira is a sixth-generation semi-submersible drilling rig built to the Moss Maritime CS60 design. Operated by Seadrill Europe Management, it received an acknowledgement of compliance (AoC) from the PSA in 2019.