Jadestone files environment plan for new offtake model at Stag field

Jadestone Energy has filed a revision of its environment plan for operations at the Stag field, located offshore Australia, to the Australian authorities.

The Australian petroleum regulator, NOPSEMA, said on Wednesday that Jadestone’s Stag environment plan is now under assessment.

Jadestone is the operator and titleholder of the Stag Field Production and Export Facility located in permit area WA‐15‐L, approximately 60 km northwest of Dampier.

The facility, located in approximately 49 m 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.

Namely, the owner of the Dampier Spirit Altera Infrastructure, formerly Teekay, advised Jadestone of its intention to retire the Dampier Spirit later in 2020.

As a consequence, Jadestone has 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 a number of wells; a single 2 km 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 field.

Activities also include water injection flowlines and wells to assist reservoir fluid recovery; support/ supply vessels, work vessels and tug boats/ static tow vessels supporting third-party tanker movement, facility logistics, maintenance and provisioning; and helicopter support.