Modeling pollutant dispersion scenarios in high vessel-traffic areas of the Lower Amazon River

Highlights: • There are potential risks of oil spill accidents along the Amazon River Estuary. • First dispersion pollution simulation study to test oil sensitivity maps. • Environmental impacts depend on the oil spill site, hydrodynamic and wind conditions. • Unprecedented estimate on the reach of oil spill plume impacts in the Amazon region • In just three days the oil spill would impact up to 132 km along the fragile coast. Large ships are efficient in transporting oil and its derivatives. However, they can cause spills in the event of accidents. The aim of the study is to simulate oil dispersion processes in scenarios of likely accidents with ships traveling on sea routes interconnected with Amazonian ports and with the Atlantic Ocean. Navigation routes were based on traffic data to identify risk areas, as well as to compare them to data from the environmental (oil) sensitivity index and to results of numerical simulations of plumes dispersion. These three approaches were integrated to each other in order to assess potential environmental impacts of plumes on coastal biota and human populations. Scenarios results have indicated that the rainy season is the most critical period for plumes dispersion. But, depending on the emission point, plumes tend to remain close to the coast, extend up to 132 km within 72 h, affecting the biodiversity, protected areas and water supply systems from the urban areas.