Stybarrow Decommissioning and Field Management
|Activity type||Decommissioning, dismantling or removing a facility|
|Submitted by||BHP Billiton Petroleum (Australia) Pty Ltd|
|Submission date||18 August, 2015|
|Decision date||20 October, 2015|
|Link to previously accepted EP|
Ms Bindi Gove
The Stybarrow Facility produced crude oil from the Stybarrow and Eskdale reservoirs via a single stand-alone Floating Production Storage and Offloading Facility (FPSO). The Stybarrow Facility was located in Commonwealth waters approximately 51 km northwest of the North West Cape of Western Australia and approximately 30 km north-west of the northern boundary of Ningaloo Marine Park (Commonwealth Waters) and approximately 55km west-north-west of Exmouth (refer Figure 11).
Production from the Stybarrow Facility ceased in July 2015 and the vessel sailed away in August 2015. At the cessation of production, all wells were bullheaded and valves were pressure tested and closed. Flowlines were flushed with treated seawater until the OIW content was< 30 ppm. These activities were carried out under the Stybarrow Operations Environment Plan (STHSE-E-0001). This Environment Plan covers the activities during the cessation phase.
The Stybarrow field including wellheads, pipeline route and the gas-injection well remain protected from third party vessels and shipping activities by a restricted area. Gazetted exclusion and cautionary zones are marked on nautical charts surrounding the Stybarrow FPSO and subsea facilities of 500 m and 2.5 nm (4.6 km) respective ly under the Offshore OPGGSA (Part 6.6: "Safety zones and the area to be avoided"}.
This EP describes BHP Billiton's proposed cessation activities located in Permit Area WA-32-L in Commonwealth waters (the Activity). The scope of the activities includes:
• The cessation phase where the wells, flowlines and other subsea infrastructure remain in-situ;
• Vessel-based activities including subsea inspections/ interventions;
• Vessel-based activities including subsea flowline cutting and plugging; and
• Vessel-based activities to disconnect and remove the spider buoy.
|Commonwealth waters adjacent to||Western Australia|
|Titles (or other instruments)||