For commercial reasons our client has asked to remain anonymous.
6 unmanned offshore production platforms. 8 wells. 1 pipeline.
Deferred CAPEX for around a decade.
Our Middle-Eastern client's core business is to source and market natural gas. They have a portfolio of gas processing facilities, exploration and production assets.
Our client took ownership of a field when the previous operator withdrew from the concession agreement. Our client asked us to support fully in evaluating, managing and maintaining the newly acquired, mature infrastructure. The field is nearing the end of its economic life. It was discovered in the mid 1960s, with start-up production beginning two decades later.
Our client wanted to safely extend the life of six normally unmanned installation platforms, which together with eight wells and a gas pipeline form a production installation hub located 45km offshore. The success of this work would defer Plug & Abandonment (P&A) and decommissioning activities, enabling our client to invest capital in significantly more valuable projects.
How we helped
Assets were operating beyond their intended design life. We focussed on two main areas to support both our client’s immediate needs and strategic aims.
- A cost-risk evaluation of current field assets and their integrity status.
- Long-term monitoring and maintenance plans to defer large CAPEX spend for P&A and decommissioning.
Our end-to-end service combined our leading industry expertise across key disciplines. This included:
- Delivering asset, pipeline and wells integrity services to understand current conditions in detail and identify any major risks or problems in extending field life
- Developing cost-efficient rectification plans to resolve critical issues
- Providing contract and procurement assistance
- Supervising the execution of rig solutions, offshore
- Putting in place an effective wells management system, standards and procedures
- Establishing comprehensive quality, health, safety and environment (QHSE) documents, encompassing an emergency response plan in case of an oil spill and to cover medevac and security matters.
We also supplied our client with subject matter experts on an ad hoc basis, as needed.
Well suspension solutions
Our study identified two wells with high risk integrity concerns. As these were served by the same platform, it made economic sense to suspend both wells simultaneously.
Alongside our client, we planned, evaluated and executed rig-based intervention solutions to resolve the immediate safety critical situations.
- The original suspension plan for one well 1 was to kill the well and reinstate dual surface barriers, before removing tubing and setting a cement plug. During operations, this plan was modified due to corrosion binding of the wellhead. Instead, we isolated the reservoir, significantly reducing well pressure to below the maximum allowable annular surface pressure (MAASP).
- The suspension plan for well 2 included blowing down pressures and displacing the well to kill weight brine. The well was suspended with a permanent bridge plug and cement. After suspension, pressures were recorded as 0 ps, confirming a successful isolation from the reservoir.
Each well is now in a much safer condition, with dual barriers installed on the outlets of both. Essential, ongoing monitoring is now much easier. It will also be a simpler task to re-connect the wells in the event of future operations.
- Corrected pressing safety critical conditions
- Saved cost compared with conducting a full P&A project, deferring unnecessary CAPEX for 10 or so years and freeing up capital for major projects elsewhere
- Enabled longer-term plans for the field to be cost-effectively aligned, leaving open the opportunity to develop the field further.