Perth-based Woodside Petroleum Ltd. has begun the process of shutting down and decommissioning its Enfield oil field on the North West Shelf off Western Australia.
The company has submitted an environmental plan for the work with the Australian National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) to cease production, decommission, dismantle, and remove facilities from the field, which lies in licence WA-28-L in the Carnarvon basin about 50 km northwest of Exmouth.
The field was developed using subsea wells, manifolds, and flowlines tied back to the Nganhurra floating production, storage, and offloading vessel. It has been on stream since 2006.
The plan calls for Woodside to flush the subsea and topside infrastructure prior to disconnecting the FPSO from the field. The riser turret mooring will also be removed.
This will involve first plugging and abandoning the subsea wells, disconnection of the risers and electrohydraulic umbilical, removal of the buoyancy modules, and disconnection of the mooring lines from the riser mooring.
Plugging and abandonment of remaining wells and decommissioning of remaining subsea equipment will be subject to future stakeholder consultations and submission of more environmental plans.
NOPSEMA’s decision about the environmental submission is expected at the beginning of September.
Woodside is operator of the field and is partnered by Mitsui E&P Australia.
