Risk-Based Abandonment-Prioritization Strategy for Inactive Subsea Wells

This paper describes how an exploration-and-production company successfully developed and applied a qualitative risk-based abandonment-prioritization strategy for an inventory of inactive subsea wells. The exercise entailed a qualitative-assessment methodology using 25 well-integrity-related criteria. An aggregate of weighted scores was subsequently applied to the company’s corporate risk-assessment matrix on the basis of the escalation potential in the event of a loss of containment. The results clearly highlighted the wells with the highest risks.

Well History

The inactive subsea wells relevant to the exercise are distributed across the central North Sea in water depths ranging from 244 to 474 ft.