Project Overview

An operator with five subsea exploration and appraisal wells drilled between 1987 and 1990 — all production-tested and temporarily abandoned — required a comprehensive engineering study to define a compliant permanent abandonment pathway. None of the five wells met permanent abandonment standards as-found. SPD was engaged to assess the current well status, identify all compliance gaps and develop a technically rigorous, cost-effective methodology to achieve permanent abandonment.

SPD’s Approach

A rig-based approach using a jack-up was recommended for all five wells. Full drilling capability is required to drill out existing plugs, cut and pull long casing strings of up to 2,000m, and re-cement barriers to OEUK standard. Rigless LWIV options were assessed and ruled out. New technologies including perforate-wash-cement (PWC), resin systems and bismuth alloys were evaluated — PWC was confirmed viable under rig supervision to reduce casing pull operations.

Results & Value Delivered

✔ Full Barrier Gap Analysis — Well-by-well analysis completed against OEUK/NORSOK requirements.

✔ Rig-Based Methodology Defined — LWIV option formally ruled out with clear technical justification.

✔ Compliance Pathway Delivered — Operator provided with a clear, regulatory-compliant pathway to permanent abandonment.