Offshore Well Abandonment: Challenges and Approach with DNV GL Guideline of Risk Based Abandonment

When subsea fields are reaching the end of their productive lives, the aging assets will need to be decommissioned, of which the well abandonment operations can amount to two thirds of all decommissioning expenditures.  Therefore, reducing the cost associated with this activity, without compromising safety is the premium goal owners are pursuing, especially with the current economic climate and low oil prices. It is imperative for the industry to explore and expand the current approaches in order to shrink the bill, of which can include: new strategic thinking; new methodologies; and the development of new and innovative technologies. To assist the industry in finding the most cost effective solutions in the offshore well Plug and Abandonment (P&A) area, DNV GL recently released a guideline for the risk based approach to plug and abandonment of offshore wells, which provides an alternative approach to the current access abandonment design. This paper presents the challenges of offshore well P&A in the Gulf of Mexico, the possible approaches to address these issues, and describes how the DNV GL guideline can be used for offshore well abandonment activities.