Griffin Field Decommissioning
|Activity type||Decommissioning, dismantling or removing a facility|
|Submitted by||Woodside Energy (Australia) Pty Ltd|
|Submission date||04 April, 2022|
|Status||Under assessment (with titleholder)|
|Link to previously accepted EP|
BHP Petroleum Pty Ltd (BHP) is planning for the safe and sustainable closure of the Griffin Development in petroleum licence WA-10-L off the coast of Western Australia, 65 km north-west of Onslow and 94 km north-east of Exmouth, in a water depth of approximately 130 m.
The removal of the majority of the Griffin facilities (well heads, flowlines, subsea ancillary equipment) within the WA-10-L and WA-12-L licences is subject to an environmental approval currently under assessment. The Gas Export Pipeline (WA-3-PL) is subject to a separate environmental approval currently also under assessment.
The remaining equipment, covered under this EP is:
• The riser turret mooring(RTM) lower compartment (Ballast- steel Iron ore and concrete)
• 12 RTM steel anchors
• 1 PLEM steel and concrete pile foundation
• 4 distribution skid pile foundation (steel and concrete)
• 6 mid- depth buoys (MDB) concrete gravity base structures
The scope of the EP includes the decommissioning the equipment in situ in perpetuity. An assessment found that the leave in situ decommissioning option was preferred as it meets legislative requirements, is technically feasible, provides equal environmental outcomes, and has fewer health and safety risks when compared to removal. Impacts associated with the perpetual presence of the equipment include long-term degradation of the materials and potential displacement or interactions with future trawl fishers. These impacts and risks have been demonstrated as ALARP and acceptable in the EP.
The petroleum activities program will end on acceptance of this EP by NOPSEMA and the expected duration of the activity will be zero days.
|Commonwealth waters adjacent to||Western Australia|
|Titles (or other instruments)||