Ocean Science Consulting Limited (OSC) is excited to announce publication of its latest peer-reviewed paper, ‘A Framework for a Net Environmental Benefit Analysis Based Comparative Assessment of Decommissioning Options for Anthropogenic Subsea Structures: A North Sea Case Study’. This paper is published in Frontiers in Marine Science and was a collaboration between OSC’s Managing Director, Dr Victoria Todd; Senior Analyst, Dr Laura Williamson; and colleagues at Montrose Environmental including Joseph P. Nicolette; Nicholas Nelson; Michael Rockel; Mark Rockel; Alex Testoff, and Larry Johnson.
Currently, decommissioning offshore Oil & Gas (O&G) structures in the North Sea follows Comparative Assessment (CA) Multiple-Criteria Decision Analysis (MCDA) guidelines based on the Oslo and Paris Convention’s (OSPAR) Decision 98/3. However, existing CA MCDA processes can be arcane, vague, hard to replicate, biased, and give little consideration to multigenerational benefits of subsea structures.
This paper adapts the Net Environmental Benefit Analysis (NEBA) framework for offshore O&G assets, presenting one that is more science-based, transparent, quantitative, and coherent than previous approaches. It does this by 1) incorporating quantified metrics including multigenerational ecosystem service benefits and risks, 2) excluding front ranking or weighting of metrics, and 3) providing consistent graphical displays to support visual differentiation of options and metrics.
Different options for decommissioning (e.g. in-situ management, full removal, and multiple partial removal options) are compared on factors such as net ecosystem service value, health and safety risks, benthic biomass, greenhouse gas emissions, and implementation costs. A North Sea case study is presented worked through with this new framework. The key finding of this approach suggests that Protect-in-Place with a 15 m reef is the most suitable decommissioning option for this example platform.
With hundreds of O&G platforms globally due to be decommissioned in the coming years, this paper presents a much-needed practical framework to optimise decommissioning strategies. The NEBA-CA framework can assist decision makers in maximising ecological, economic, and social benefits while manage site risks and costs. If you think NEBA-CA could be used at your site, then please get in touch with us today to discuss how we could put it into practice. We also provide ROV and ornithological surveys, pre- and post-decommissioning.