The proposed Greater Western Flank Phase 2 (GWF-2) development represents the next phase in gas supply to the existing North West Shelf (NWS) Project’s Goodwyn Alpha platform (GWA). GWF-2 consists of eight production wells developed in four drill centres and tied back to GWA via a subsea pipeline, around 36 km in length.
The NWS Project is planning to make a final investment decision in 2H 2015. The nominated titleholder for this activity is Woodside Energy Ltd, on behalf of a Joint Venture comprising Woodside Energy Ltd, BP Developments Australia Pty Ltd, Japan Australia LNG (MIMI) Pty Ltd, Chevron Australia Pty Ltd, Shell Australia Pty Ltd, BHP Billiton Petroleum (North West Shelf) Pty Ltd and China National Offshore Oil Corporation (CNOOC) North West Shelf Private Limited.
The current GWF-2 development seeks to develop six hydrocarbon fields in the vicinity of GWA, these being Keast, Dockrell, Sculptor, Rankin, Lady Nora and Pemberton. The fields are located in production licences WA-5-L, WA-6-L, WA-24-L and WA-51-R in in Commonwealth waters approximately 135 km north-west of Dampier.
GWF-2 includes drilling, completing and testing of eight development wells within the Keast, Dockrell, Sculptor, Rankin, Lady Nora and Pemberton hydrocarbon fields, at water depths of approximately 79- 130 m. Based on current schedules, drilling of the GWF-2 development wells will commence in 2H 2016 and is expected to take approximately 60 days per well to complete. The proposed wells will be drilled by a moored mobile offshore drilling unit (MODU). A pile based mooring system may be required for the Sculptor Rankin and Lady Nora Pemberton well centres.
Supply vessels will support the drill rig for the duration of drilling operations.
The installation of a 36 km flowline running from the furthest well centre (Lady Nora Pemberton) to the GWA facility is expected to take approximately eight months in field to complete. Subsea installation and commissioning of subsea hardware including umbilical to tie wells into the GWF-2 pipeline is planned to take approximately six months in field. Specialist dynamically positioned vessels will undertake pipelay and subsea hardware installation activities and will be supported by a range of other vessels including heavy lift and special purpose vessels and tugs.
GWF-2 will tie-in to the existing Greater Western Flank Phase 1 subsea isolation valve manifold and pre- commissioning of the tieback will be undertaken prior to newly installed infrastructure coming online.
The timing and duration of these activities is subject to change due to MODU/vessel availability, unforeseen circumstances and weather.