Esso Australia Resources Pty Ltd (Esso) operates the joint venture responsible for the exploration, development and production of gas and condensate from Bass Strait, offshore Victoria’s east coast. The broader Bass Strait system comprises 425 wells, 19 offshore platforms and six subsea facilities connected by more than 800km of pipelines.

This EP assesses the environmental impacts and risks associated with the operation and maintenance of the non-producing Bass Strait assets that are in cessation of production or stasis. It demonstrates how these impacts and risks are managed to ALARP. The non-producing assets and associated permit areas are shown in the location map.

The non-producing infrastructure includes 13 platforms and four subsea facilities, with water depths ranging from approximately 38m (DPA) to 402m (BKA):

• Platforms:
• Bream A platform (BMA)
• Bream B platform (BMB)
• Cobia platform (CBA)
• Halibut platform (HLA)
• Flounder platform (FLA)
• Fortescue platform (FTA)
• Kingfish A platform KFA)
• Kingfish B platform (KFB)
• Mackerel platform (MKA)
• West Kingfish platform (WKF)
• Whiting platform (WTA)
• Dolphin monopod (DPA)
• Perch monopod (PCA)
• Subsea facilities:
• Blackback subsea facility (BKA)
• Cobia 2 subsea facility (CBA2)
• Seahorse subsea facility (SHA)
• Tarwhine subsea facility (TWA)

These assets are supported by a network of subsea pipelines ranging from water depths of approximately 20m at the Victorian State waters boundary to 402m at BKA.

This EP also covers facilities that are expected to transition to CoP within the five-year EP period, including:

• Platforms:
• Barracouta platform (BTA)
• Snapper platform (SNA)
• Tuna platform (TNA)
• Subsea facilities:
• Barracouta West facility (BTW)

The EP covers activities required to safely maintain the non-producing assets, including:

• non-producing platform activities
• non-producing pipelines and subsea facilities activities
• well work, including platform-based plug and abandonment (P&A)
• inspection, maintenance and repair (IMR) activities of non-producing facilities and pipelines, including partially removed infrastructure under separate decommissioning EPs
• preparation of facilities for decommissioning
• support activities (helicopters, vessels and remotely operated vehicles (ROVs)
• ongoing environmental monitoring

This EP applies for five years from the date of acceptance.

All non-producing assets are within the Area to Be Avoided (ATBA) defined under Schedule 2 of the OPGGS Act, administered by NOPSEMA, except the PCA and DPA monopods and the BKA subsea facility and associated pipelines. The ATBA restricts unauthorised vessels greater than 200t or 24m in length. A traffic separation scheme operates to the south of the ATBA for coastal shipping, and none of the assets overlap this area.

A separate five-year EP (Bass Strait Producing EP) covers the impacts and risks associated with operating the producing Bass Strait assets.