A team of international researchers led by the Ecole Polytechnique Fédérale de Lausanne (EPFL), has conducted a real-time study of the breakdown of oil during the first 24 hours after a spill. The results were then compared to a model that the team had developed to predict the ways in which the oil changes and how various components enter the water column and atmosphere.
As predicted, the volatile hydrocarbon components evaporated with hours creating atmospheric contamination while other types disperse into the water column. By extrapolating their findings into the computer model, the scientists can now better predict what will happen in larger spills and in different environments. While there is a great deal of information on how oil changes over time during a spill, it is unusual for researchers to be in a position to study what happens in the 24 hours immediately following a spill.
Spill test conducted in area previously exposed to oil
Unlike many types of spill tests, which use other materials to estimate where the oil might spread, or laboratory tests that attempt to imitate what might happen in the ocean, in this case 4.3 cubic meters of oil were released in order to better understand the changes petroleum products go through in the first 24 hours after being exposed to the sea.
To minimise environmental impact, the researchers worked with the Dutch oil spill response agency, Rijkswaterstaat, to manage the spill and operated in an area that had previously been exposed to pollution. The tests were carried out on a warm, windy day with high wave action, which meant that the oil dispersed quickly.
Just one piece of the puzzle, as each spill is different
Comparing the results at sea with the computer model will improve predictions about what types of hazards responders and wildlife are likely to encounter in a spill. The speed at which the volatiles disperse determines the timing of the risk for respiratory impacts while aquatic organisms are affected more long term by the components dispersed into the water column.
Other participating organisations included the Royal Netherlands Institute for Sea Research (Royal NIOZ), the University of Amsterdam’s Institute for Biodiversity and Ecosystem Dynamics, the Swiss Federal Institute of Aquatic Science and Technology (Eawag), the Helmholtz Centre for Environmental Research –UFZ in Germany, and the Woods Hole Oceanographic Institute in the United States.
Resources:
Gros, J., et al. 2014. First Day of an Oil Spill on the Open Sea: Early Mass Transfers of Hydrocarbons to Air and Water. Environmental Science and Technology. 48 (16): 9400-9411. DOI: 10.1021/es502437e.
The immediate aftermath of an oil spill. Ecole Polytechnique Federale de Lausanne News Mediacom. Accessed online 19 August 2014