Oil was first discovered at the Saltire field in January 1998 from Well 15/17-16. The Saltire Platform was installed in 1992 and commenced production in May 1993. In total the platform processes hydrocarbons from the following fields:
- The Saltire field comprises three reservoirs, there are 14 platform based wells. There is also a subsea wellhead protection unit located approximately 2.5 km from Saltire platform with 3 water injection wells.
- The Chanter field comprises two reservoirs, is located 4km southeast of Saltire platform and produced via well 15/17-A13Z which was drilled from Saltire platform.
- The Iona field comprises one exploration/appraisal well and one production well drilled from Saltire platform
About the facilities
Oil was first discovered at the Saltire field in January 1998 from well 15/17-16. The Saltire”A” Platform was installed in 1992 as part of the Piper Area Redevelopment and commenced production in May 1993.
The Saltire field consists of Saltire “A” platform, the subsea Saltire Water Injection Development (WID), the subsea Chanter production system and all pipelines and umbilicals linking these assets to Piper “B” platform .The Iona field was developed via platform based wells drilled from Saltire “A” platform.
The Saltire “A platform comprises a 4 legged cross braced steel jacket substructure secured to the seabed by 16 steel piles.A large two level integrated deck is mounted on the jacket which supports accommodation, process facilities, utilities including power generation, wellheads and drilling modules and facilities.
- The Saltire “A” topsides weighing approximately 12,874 Te;
- The Saltire A substructure (jacket) is a four -legged fixed steel jacket weighing approximately 14,700 Te (including risers but excluding marine growth) and sits in a water depth of 145 m.
From the Saltire “A “platform, the processed oil was exported to the Piper “B” platform via a 40 inch pipeline buddle containing one 10 inch diameter multiphase export line ,an 8 inch diameter gas lift line and two 16 inch diameter lines .
From Piper “B”, oil was exported through a 30 inch diameter line to the Flotta terminal facilities in Orkney, while gas was exported to the St Fergus gas terminal via a 16 inch diameter gas export line.
The decommissioning of the Saltire substructure is not part of the initial decommissioning programmes (DP) and will be subject to a separate submission.
Facilities to be decommissioned
Removal, onshore dismantling, recycling and disposal of topsides, substructures and subsea infrastructure.
Multiple options are being considered for the decommissioning of the Saltire Area infrastructure, all of which have undergone a screening process to identify those that are feasible. Those feasible options for the decommissioning of the Saltire “A” Topsides, substructure and subsea facilities and pipelines have been subject to a Comparative Assessment (CA) process to determine the best options with regards to their safety, environmental, societal, technical and economic performance.