Australian regulator accepts Jadestone’s plan for new Stag field offtake model
Australia’s National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) has approved Jadestone Energy’s plan for operations at the Stag field, located offshore Australia.
Jadestone is the operator and titleholder of the Stag Field Production and Export Facility located in permit area WA‐15‐L, some 60 kilometres northwest of Dampier.
The facility, located in approximately 49 metres of water depth, produces oil from the Stag reservoir. Oil is loaded continuously to the third-party tanker at a production rate of up to 4,000 bbl/d. The CPF has been in production since 1998 with only minor modifications carried out during this time.
Historical operations at the Stag field have seen the inclusion of a floating, storage and offtake (FSO) vessel – Dampier Spirit – that has been moored in the field and receives produced oil from the central production facility (CPF), and then offtake of the cargo to a third-party tanker.
Recent operational and commercial developments have seen a shift to an operating model that requires only a third-party tanker and thereby permanent relinquishment of the FSO from the field, and therefore a revision to the current EP has been submitted.
Worth noting, the owner of the Dampier Spirit – Altera Infrastructure, formerly Teekay – advised Jadestone of its intention to retire the Dampier Spirit in 2020. According to Altera’s third quarter of 2020 results, the Dampier Spirit FSO ceased operations on the Stag field in September 2020. At the time, the vessel was anchored in Australian waters before being towed to Turkey for responsible recycling.
Therefore, Jadestone developed a new operating strategy, utilising offtake tankers to directly offload Stag crude oil, in place of the existing long-term leased FSO.
The scope of this environment plan covers the operation of the offshore facilities for a period of up to five years from initial acceptance in December 2017.
Activities associated with the facility include a fixed Central Production Facility (CPF), producing and processing oil from several wells, a single 2 kilometres long carbon steel export oil pipeline on the northeast side of the CPF connecting to a Catenary Anchor Leg Mooring (CALM) buoy via a flexible submarine hose, a third-party tanker receives oil through a flexible import hose from the CALM buoy.
Once loading is complete, the tanker departs the field for delivery of cargo to market. No offtake activity from the third-party tanker occurs in the field.
Activities also include water injection flowlines and wells to assist reservoir fluid recovery, support and supply vessels, work vessels, and tug boats and static tow vessels supporting third-party tanker movement, facility logistics, maintenance and provisioning, and helicopter support.