After delivering energy to Australia for over 50 years, many of the Bass Strait fields are now reaching the end of their productive life. As a result, Esso has committed to the progressive decommissioning of the Bass Strait production network.

Campaign #1A is the second execution campaign in the Bass Strait decommissioning program and involves the recovery and removal of selected umbilicals, flexibles and associated subsea property. Approximately 47 kilometres of umbilicals and flexibles will be removed as part of this campaign.

The Operational Areas (OAs) are located in Commonwealth waters between approximately 16 and 90 kilometres from the east coast of Victoria. The 13 OAs encompass all planned activities and are defined as approximately 500 meters either side of the infrastructure. The total combined area of the OAs is approximately 73km2.

Recovery and removal activities may include infrastructure unburial, sediment relocation, marine growth removal, and cutting and recovery of umbilicals, flexibles and associated subsea property. Umbilical and flexible removal will be undertaken using cut and lift, reverse lay, or a combination of both methods.

The works are expected to be undertaken by a recovery vessel, likely to be a construction support vessel equipped with a flexibles/umbilical’s recovery spread, supported by remotely operated vehicles and dedicated recovery tooling. Support from additional marine vessels may be utilised as required. Subject to vessel availability, other suitable vessel types may be used, including dive support, pipelay or reel lay vessels. Smaller support vessels and helicopters may provide personnel transfer and logistical support.

The activity may occur any time between 2028 and 2031 and is expected to be approximately two months in duration.