Santos WA Northwest Pty Ltd (Santos) on behalf of Santos Offshore Pty Ltd operates Reindeer wellhead platform (WHP) and associated wells within permit area WA-14-L and the offshore section of the Devil Creek Gas Supply Pipeline (DC supply pipeline; WA-18-PL) in Commonwealth waters.
The infrastructure on title is collectively referred to as the Reindeer facilities which comprise:
• The WHP infrastructure,
• An offshore section of the DC supply pipeline in Commonwealth waters, ~43 km long
• Three wells tied back to the WHP
• An open ocean well (Reindeer-1) that is temporarily abandoned and not connected to the WHP.
The portion of the DC supply pipeline in state waters is managed under the Devil Creek Gas Supply Pipeline and Sales Gas Pipeline Operations EP (EA-14-RI-10001/01) under WA State jurisdiction.
The Reindeer field is approaching the end of its economically viable production life and is expected to cease production in late 2024 or early 2025. This EP has been updated to include cessation of production (CoP) and preservation activities. The CoP phase commences when the facility reaches its end of field life and has been shut-in and depressurised
The activities that may be undertaken under this EP, include the following:
• Operations phase:
- Presence of infrastructure on title
- Operation of the WHP, wells and DC supply pipeline
- Transporting unprocessed condensate from the Reindeer field to DCGP
- Vessel based activities associated with operations; and
• CoP (preservation) phase:
- The facilities are cleaned and flushed to remove hydrocarbons and contaminants
- The facilities are then preserved using treated seawater or inert gas such as nitrogen
- The Reindeer facilities will remain in preservation phase until a decision is made to either repurpose the facilities or decommission all, or part of the facilities; and
• Inspection, maintenance, monitoring and repair (IMMR) may be undertaken during the operations phase or CoP phase and includes activities such as:
- Subsea and DC supply pipeline integrity and corrosion management
- Subsea, pipeline and seafloor imaging surveys
- Plant inspection, maintenance and modifications
- Well intervention, temporary abandonment or suspension
- Bird deterrence on the WHP.
The Reindeer gas field is located within permit area WA-41-L, ~80 km northwest of Dampier. The closest Australian Marine Parks (AMPs) are the Montebello AMP and Dampier AMP, which are located ~32 km and 53 km respectively from the nearest boundary of the operational area. Water depths range from 58 m to 38 m.
The Reindeer facilities operate 24 hours a day, every day of the year and all activities could occur at any time of year, (day or night). Individual general IMMR campaigns are expected to take around 14 days. Campaigns associated with CoP are expected to take around 30 days. Timing and duration of these activities is subject to change due to project schedule requirements, vessel availability and weather.
Vessels are used to support all offshore activities. Visits to the WHP are generally conducted via helicopter, using the helideck, but may also be conducted via vessels.