Woodside is seeking environmental approval to undertake petroleum activities to support the cessation of operations at the Balnaves oil field. The Balnaves infrastructure is located in production licence WA-49-L in Commonwealth waters. The Balnaves oil field is approximately 48 km north-west of the Montebello Islands and 75 km north-west of Varanus Island. Water depths over the field vary from 110 m to 160 m.
Activities are anticipated to be undertaken within a 6-12 month timeframe.
 
Activity Summary
Activities to be undertaken include:
Ongoing preservation of the Balnaves subsea systems and riser turret mooring (RTM) (also known as disconnectable turret mooring) until RTM removal.
Vessel monitoring, including subsea inspections by remotely operated vehicle of the Balnaves field and RTM.
Disconnection and removal of flushed flowlines from manifold and installation of pressure caps on the well heads.
Disconnection and recovery of flushed spools from well heads and removal of manifold and supporting infrastructure.
Disconnection and removal of flushed risers and umbilicals.
Disconnection and removal of RTM (and associated facilities).
Ongoing preservation of the Balnaves subsea systems until the wells are plugged and abandoned.
 
Plugging and abandonment of wells and decommissioning of remaining subsea infrastructure will be covered in future environment plan submissions.