Modeling of accidental oil spills at different phases of lng terminal construction

Abstract

Accidental oil spills not only deteriorate biodiversity but also cause immediate threats to coastal environments. This study quantitatively investigates the initial dispersion of spilled oil using the environmental fluid dynamics code (EFDC) model, loosely coupled with an endorsed oil spill model (MEDSLIK-II) accounting for time-dependent advection, diffusion, and physiochemical weathering of the surface oil slick. Focusing on local contributing factors (i.e., construction activities) to oil dispersion, the current model is applied to likely oil spills occurring at three different phases of the Songdo LNG terminal construction on a reclaimed site in South Korea. Applied phases pose detailed ship collision scenarios generated based on a proposed construction plan of the terminal. The effects of permeable revetments, required for reclamation, on the currents were also investigated and applied in subsequent oil spill modeling. For each scenario, the simulated results showed distinct patterns in the advection, dispersion, and transformation of the oil slick. Oil absorption into the coast, which causes immense damage to the coastal communities, is found to be highly dependent on the tidal currents, volume of oil spilled, and nearby construction activities.