Mitigation associated with oil spill events in sea environment depends largely on the design and implementation of adequate contingency plans, which should incorporate the simulation of the spill dispersion patterns and the characterization of marine and coastal areas that could be affected. This paper is focused on the development of an actual emergency response plan following a major sea accident verified in the Liguria Sea and causing a fuel spill of about 600 m3. The theoretical approach relies on a model developed on a Lagrangian scheme, running decoupled from hydrodynamics, for predicting fate of hydrocarbons and covering both the transport and the weathering. Simulations were performed on the basis of daily updated meteo-hydrodynamics forecast by the operational circulation model of the Liguria Sea (MIKE 3 HD), reports of sightings of material from the Coast Guard and images of the spill captured by Copernicus Sentinel-1 satellites. The reliability of the modelling was assessed via analysis based on actual oil trajectories. A remarkable agreement was verified between calculated oil forecast, satellite images and actual empirical sightings of material, confirming the effectiveness of the combined modelling approach in oil spill risk assessment and in setting-up emergency planning.
