Deepwater Field Decommissioning Plan Review for Mauritania
Case for Action
Mauritania’s first deep water field development was to be decommissioned by the Operator, an experienced foreign NOC. The field facilities comprised 15 subsea wells, associated subsea hardware, risers and umbilicals, and a leased FPSO moored in 800 meters of water. At the time, the Government of Mauritania had not yet developed rules, regulations and processes for decommissioning, which was particularly concerning for a first-time application, even by an experienced Operator, to a complex installation. To ensure all aspects of the decommissioning were adequately carried out, the consultants advising the Government of Mauritania regulatory agency reached out to Endeavor Management to provide technical, regulatory, and environmental management review of the Operator’s decommissioning plans prior to approval by the relevant authorities.
Endeavor Management Solution
Endeavor Management undertook the review by
- Quickly assembling a team of well engineering, subsea, FPSO, regulatory and environmental management advisors to review the Operator’s plans,
- Considering worldwide decommissioning best practices (from Norway, UK and USA) as a regulatory basis for the review,
- Rigorously assessing the risks associated with the field decommissioning, and establishing whether the Operator’s proposals reduced said risks to levels that were as low as reasonably practical (ALARP),
- Where the Operator’s plans were considered deficient, providing practical alternative suggestions which would reduce risks to ALARP levels,
- Presenting the results of the review to Government officials in both plenary and breakout formats to ensure all questions were fully addressed and the responses understood.
Endeavor Management’s advisers found that the Operator had prepared thorough, well-reasoned abandonment and decommissioning plans (A&DP) for the FPSO and subsea systems. However, the well systems A&DP was found to require significant clarification in terms of the sequencing of the proposed steps and in terms of the number and robustness of the independent barriers placed during the temporary suspension of the wells.
Endeavor’s recommendation was that the A&DP be conditionally approved subject to several actions being completed, the most salient of which were:
- Operator addressing gaps in the Environmental Impact Statement (EIS)
- Operator clarifying and agreeing definition of the maritime exclusion zone with Government Stakeholders
- Operator improving temporary well suspension plans to increase robustness and number of permanent barriers.
- Operator and/or Government of Mauritania to define mechanisms to ensure fulfillment of future financial obligations, insurance coverage, compliance with international law.
- Operator completing an updated seabed and subsea infrastructure survey prior to commencement of decommissioning work.
The Mauritanian Government Regulator appreciated the thoroughness of Endeavor’s work and the professionalism of our Advisors, particularly in the attention applied to safety-related issues and ensuring that all the activities were performed in accordance with global best practices. As a result of this engagement, Endeavor Management has been invited to support other projects for the Government of Mauritania.