Auk South Facility - Xodus Group
Client: Talisman
Location: Central North Sea

Successfully evaluating field redevelopment options.

Xodus Group’s integrated team assess tie-backs, new fixed / floating platforms, bridge linked platforms and existing plant development for the Auk South facility.

Talisman Energy UK Ltd (TEUK) took ownership of the Auk South facility from Shell in 2006 and identified additional reserves in the Auk Central / Southern reservoir areas. To exploit them, an upgrade of the Auk South facility was required. Xodus was tasked with assisting TEUK in evaluating a number of options for Auk South including new drilling, accommodation, processing, utility and flaring facilities.

Key factors in the evaluation process included:

  • Early elimination of multiple field development options
  • Wellbay configurations to maximise the limited availability of jack-up rigs
  • Maintaining appropriate features to manage hydraulic workover units

Assignment scope
Eight different options were considered and thoroughly assessed. Working closely with TEUK, our multidiscipline team:

  • Provided comparison capital expenditure (CAPEX) costs for full facility options and individual module components
  • Assessed existing and new plant to process revised production profiles
  • Assessed jacket configurations – three or four leg, battered, twisted, driven or suction piled – and completed relevant static and dynamic structural analysis for the preferred options
  • Prepared equipment / major pipework layouts for all options including tree, flowline routing and manifold configuration in and around a 12 slot wellbay
  • Completed reliability analysis on single process train, mechanical handling study and As Low As Reasonably Practicable (ALARP) reports
  • Considered a primary structure arrangement including topsides, bridge and flare boom
  • Developed process, discipline and risk workscopes through Front End Engineering Design (FEED) to allow early detailed design to commence
  • Provided processing options and preliminary sizing of major equipment defined using HYSYS, in-house sizing tools and extensive vendor liaison
  • Provided process and utility flow diagrams including heat and mass balance
  • Investigated the effects of radiated heat and gas cloud dispersion based on output from hazard analysis software tool, Phast
  • Conducted a risk workshop on costs / schedule and technical aspects with a report including weighted results utilising @RISK risk and decision analysis software to develop probabilities
  • Developed CAPEX costs for module / equipment design, purchase, fabrication, installation and commissioning using an in-house estimating tool and QUE$TOR cost estimation software
  • Developed a detailed scope of work, equipment lists, specifications and datasheets
  • Developed detailed layouts, routing and weight estimates to facilitate early detailed design
  • Developed a full suite of safety philosophies.


  • Successful execution of a 19,500 manhour, 60 week overall study and pre-FEED programme on time and within budget while maintaining a significant client and subcontractor interface
  • Through close collaboration with TEUK, multiple options were streamlined into two preferred options, each with three derivatives
  • Successful pre-FEED expanded into completing extensively detailed multidiscipline input to allow the project to progress into early detailed design.