NWS and Julimar Exploration Wellhead Decommissioning
|Decommissioning, dismantling or removing a facility
|Woodside Energy Ltd
|20 December, 2023
|Under assessment (with titleholder)
|Link to previously accepted EP
Woodside is planning to decommission thirty-six historical exploration wells located across the North West Shelf of Western Australia. Thirty wells are located in Commonwealth waters around 117 km northwest of Dampier in North West Shelf permit areas WA-3-L, WA-9-L, WA-11-L, WA-5-L, WA-24-L, WA-56-L, WA-57-L, WA-58-L, WA-1-L, WA-16-L, and WA-52-L. Six wells are located in Commonwealth waters around 170 km northwest of Dampier in Julimar permit area WA-49-L. Twenty of the wells are currently accepted by the relevant regulator as permanently abandoned. This means permanent plugs have been installed in the wells to prevent hydrocarbon release to the environment. The remaining sixteen wells are currently being assessed for their suitability to be accepted as permanently abandoned.
Activities under this EP include ongoing management of wells including inspection, maintenance and repair (IMR), and removal of wellheads and associated infrastructure for wells accepted as permanently abandoned. IMR activities may include inspection of wells to confirm adequacy of barriers for permanent abandonment. Wellheads will be removed using an abrasive water jet cutting method, mechanical internal cutting tool or diamond wire saw. Activities are anticipated to commence around Q1 2024 with the removal of wellheads accepted as abandoned. Additional campaigns will be planned over the life of the EP to conduct IMR and remove wellheads for wells that become accepted as permanently abandoned. Activities will be completed from an offshore support vessel, which may be supported by a general support vessel. The vessels will operate on dynamic positioning (DP) and is anticipated to not anchor/moor on the seabed.
IMR activities are expected to take up to 3 days per well, where required. Removal and recovery activities are expected to take approximately 3 days per well, however could take up to 10 days per well. Duration of activities is subject to change due to project schedule requirements, vessel availability, weather or other unforeseen circumstances. When underway, vessels are expected to operate 24 hours per day for the duration of the activities