State-of-the Science of Dispersants and Dispersed Oil in Arctic Waters

Chemical dispersants were employed on an unprecedented scale during the Deepwater Horizon (DWH) oil spill in the Gulf of Mexico, and could be a response option should a large spill occur in Arctic waters. The use of dispersants in response to the DWH spill raised concerns regarding the need for chemical dispersants, the fate of the oil and dispersants, and their potential impacts on human health and the environment. Concerns remain that would be more evident in the Arctic, where the remoteness and harsh environmental conditions would make a response to any oil spill very difficult. An outcome of a 2013 Arctic oil spill exercise for senior federal agency leadership identified the need for an evaluation of the state-of-the-science of dispersants and dispersed oil (DDO), and a clear delineation of the associated uncertainties that remain, particularly as they apply to Arctic waters. The National Oceanic and Atmospheric Administration (NOAA), in partnership with the Coastal Response Research Center (CRRC), embarked on a project to seek expert review and evaluation of the state-of-the-science and the uncertainties involving DDO. The objectives of the project were to: identify the primary research/reference documents on DDO, determine what is known about the state-of-the-science regarding DDO, and determine what uncertainties, knowledge gaps or inconsistencies remain 689559 regarding DDO science. The project focused on five areas and how they might be affected by Arctic conditions: dispersant efficacy and effectiveness, physical transport and chemical behavior, degradation and fate, eco-toxicity and sub-lethal impacts, and public health and food safety. The Louisiana University Marine Consortium (LUMCON) dispersants database was used as a source of relevant literature generated prior to June 2008. The CRRC created a database that compiled relevant research thereafter. The six to ten experts on each of the panel were from academia, industry, NGOs, governmental agencies and consulting. Despite the fact that their scientific perspectives were diverse, the panelists were able to generate hundreds of statements of knowns and uncertainties about which all of the members agreed. This required detailed discussion of 1000s scientific papers. While the cutoff date for literature considered was December 31, 2015, the vast majority of the findings are still relevant and most of the uncertainties remain. As the ice in the Arctic diminishes and maritime development and activity increase, these five documents can inform discussions of the potential use of dispersants as a spill response option in both ice-free and ice infested Arctic waters.