Jadestone Energy (Eagle) Pty Ltd (Jadestone Energy) plans to continue monitoring of two temporarily abandoned wellheads, Sea Eagle-1 and Tahbilk-1, in the Montara field via vessel-based activities. Sea Eagle-1 was drilled and subsequently suspended in 2008, and Tahbilk-1 in 1990.

To date a remote monitoring system has been installed on the wells and is this may require maintenance over the life of the EP. This would be conducted via ROV Surveillance. This EP describes the inspection and maintenance activities on the wells.

Sea Eagle-1 is within Production Licence AC/L8 and Tahbilk-1 is within production Licence AC/L7 within the Montara field which lies approximately 690 km (373 nautical miles) east of Darwin in a water depth of approximately 80 m in Commonwealth waters of the Timor Sea.

Following a recent well integrity review, the potential for a loss of well control during suspension has been assessed as not credible and has therefore been removed from the Environment Plan (EP). The revised worst-case spill scenario is now limited to a diesel release from a vessel collision, which has resulted in a substantial reduction in the Environment that May Be Affected (EMBA). This has triggered a revision in part to the EP in 2025 and updates have been undertaken pertaining to the change in EMBA, including the existing environment, spill response activities and consultation. This also includes an updated OPEP to reflect this change.