Dispersant

A dispersant is a surfactant-solvent formulation applied to spilled oil to break the slick into fine droplets that mix into the water column and biodegrade faster. Products such as Corexit EC9500A lower oil-water interfacial tension so wave energy disperses the oil instead of leaving it on the surface or stranding it on shorelines. Use is governed by net environmental benefit analysis (NEBA): the case is generally clear in open water deeper than about 10 to 20 m, where dilution is high and sensitive shoreline or seabed habitats are not directly exposed. Application is aerial, vessel-mounted, or subsea, and is subject to regulatory pre-approval.