Case Study No 11 – Abandonment: Decommissioning Activities – UK North Sea
In 2008 the decision was reached by Hess UK and the respective field partners to commence the cessation of production, decommissioning & divestment activities for firstly the Fife, Fergus, Flora and Angus (FFFA) fields which had been in production via the Uisge Gorm FPSO and then almost exactly a year later the Ivanhoe & Rob Roy (IVRR) fields serviced by the production unit AH001 FPF.
Challenging planning timescales meant that both projects would have to run simultaneously sharing opportunities to create work synergies but with a single remit to completely remove both the topsides production facilities, all subsea infrastructure including pipelines and fully plug and abandon the 33 wells leaving the seabed in a near left state as had been found. This same extensive scope also meant it was to become the largest single subsea decommissioning project of its type undertaken to date globally.
The FFFA fields / Uisge Gorm FPSO were located 211 miles SE of Aberdeen in a water depth of 71 metres and had produced 100 mmbbls oil over a period of 13 years. The IVRR fields / AH001 FPF were located 110 miles NE and in water depth of 140 metres and over a 20-year period had produced more than 220 mmbbls oil. In addition to the Drilling Rigs the project saw some 29 separate vessels complete a variety of work scopes accumulating over 1,223 days in operations infield.
Ultimately, both the projects were completed over a period of 7 years, exceeding all HSE targets, achieving all objectives and at a cost of just under $1 billion also under budget.
ASG’s Boyd Angus was the HSE Manager for the Project and saw it through its complete lifecycle, from start to finish and was accountable for all aspects of the projects HSE Management. From outset, the highest possible EHS performance standards were demanded by project management. Year on year HSE performance excellence remained the projects main priority and were ultimately achieved with the project team achieving OGP 1st Quartile performance levels in TRIR, project team reaching multiple company overall performance awards and externally authority / partner & regulator recognition and ultimately industry (IADC) recognition for the Drilling Rig involved in the P&A works.