Cement Support Tool Assists Critical P&A Through a Deepwater Interception Well

Well abandonment in deepwater environments presents unique technical and operational challenges, particularly when the integrity of the original wellbore is degraded, and an interception well is needed. In such scenarios, conventional abandonment techniques may prove insufficient or unfeasible, necessitating innovative approaches to ensure regulatory compliance and long-term well integrity. This paper presents a case study involving the abandonment of a compromised deepwater well, where the failure of the original structure required the drilling of an interception well to enable a safe and effective plug and abandonment (P&A) operation. The complexity of this operation was increased by the limited space available within the intercepted wellbore, which restricted the use of traditional cement placement methods such as viscous pills. These limitations presented a significant risk to the successful placement of a permanent cement barrier, which is essential for isolating the reservoir in compliance with local regulatory requirements. To address these challenges, the engineering team identified and deployed a Cement Support Tool (CST), a mechanical device designed to provide a stable foundation for cement placement in geometrically constrained environments. The CST was strategically positioned just above the obstruction—commonly referred to as the "fish"—within the interception well. This placement enabled the creation of a static base for the cement slurry, preventing fluid migration and ensuring the integrity of the barrier. The use of the CST not only facilitated the successful placement of the cement plug but also eliminated the necessity for additional remedial operations, thereby reducing rig time and minimizing operational risks.