Project Profile
Location: 175 miles east-southeast of Aberdeen, block 30/17a, licence number P032, in the Central North Sea, UK
Reserves: 70 million barrels of oil
Water Depth: 80m
The Janice oil field is located in the first-round block 30/17a, licence number P032, in the Central North Sea. It lies approximately 175 miles east-southeast of Aberdeen, 5km to the south of BP\'s Clyde platform and 12km away from Shell\'s Fiulmar field. The field lies in a water depth of 80m. The field was discovered in 1990 with a well drilled by Phillips Petroleum, using the semisubmersible Dixilyn Field 96. Kerr-McGee acquired an interest in the licence block in 1995. It earned a total interest of 50.9% through drilling two successful appraisal wells during 1995 and 1996. A third successful appraisal well was drilled in late 1996. Kerr-McGee became the operator in May 1996. The producing horizon lies in the Jurassic section.
DEVELOPMENT
In early August 1997, the management of the Janice field gained partner approval. In mid-September, the UK Department of Trade and Industry (DTI) followed this by granting the field Annex B development approval. The field was to be developed using horizontal and high-angle oil-production and water-injection technology.
RESERVES
Recoverable reserves are estimated at more than 70 million barrels of 37° API gravity crude oil, and production was expected to peak by the first half of 1999. Extra processing capacity is available to allow Janice to serve as a hub for future developments. The Janice development plans envisage ten subsea wells, tied back to a floating production unit (FPU) using individual flowlines and risers. Of the ten wells, six are intended to be oil producers, while four have been planned as water injectors. This configuration will maximise the economic reserves and deliver the peak production forecasts of 50,000 gross barrels of oil per day.
PRODUCTION
Janice has been developed by recompleting two of the existing appraisal wells, as well as drilling an additional production well and a water-injection well for the production start-up. Up to seven additional wells have been also planned. Wells are located in a single subsea cluster, which is 450m southeast of Janice A. Coflexip Stena Offshore was awarded the contract for the installation of a mid-water arch design, in order to support the risers and umbilicals connecting the subsea installation to the Janice A platform. One feature of the design is the use of a riser bend limiter and a hold-back clamp, tethered to a gravity base. This maintains the riser and umbilical configuration, whilst securing it against wave action in a 100-year storm.
**Janice field: decommissioning programme approved by BEIS (in parallel with decommissioning of Affleck and James fields) and next phase under way: wells plug and abandon (P&A) to be executed by end-Q2 2018, window until end-2018. Remaining subsea infrastructure removal to be executed by end-2020, window until Q2, 2022. Debris clearance and final survey to be executed between Q4 2020 and Q1 2021, window until end-H1 2022. Close-out report to be executed between Q1 2022 and end-H1 2022, window until end-Q3 2022. Projected costs disclosed to UK Department of Business and Energy (BEIS) but not publicly released.** DF, 03/01/2018
Operators:
Kerr-McGee: Operator with 50.9% interest
ConocoPhillips: 49.1% interest
Maersk
Contractors:
Bibby Offshore: provide subsea construction and inspection, repair, and maintenance (IRM) services
Coflexip Stena Offshore: Installation of a mid-water arch design, in order to support the risers and umbilicals connecting the subsea installation to the Janice A platform
Harkand: Subsea inspection of FPSO contract
Petrofac: engineering services including concept, front-end engineering, detail design, workpack development, and procurement and document control
Viking SeaTech UK: Secured a long-term North Sea contract with the UK business of Maersk Oil. The agreement is for the supply of rig move equipment and storage services. It covers a fixed period of three years and also contains options for multiple extensions. As part of the arrangement Viking SeaTech will keep Maersk Oil’s equipment safe and secure at their premises so it is ready for use in combination with their own for each project stage. The company will support Maersk’s assets in the Dumbarton, Gryphon and Janice fields. The schedule includes the use of the Sedco 704 semi-submersible. (October, 2015)
Maersk Supply Service: Engineering, project planning, and managing the scope of the subsea decommissioning. (September, 2016)