In Situ Oil Spill Countermeasures in Ice-Infested Waters: A Modeling Study of the Fate/Behaviours of Spilled Oil
ABSTRACT The expansion of offshore oil and gas and marine transport activities in the Arctic have raised the level of risk for an oil spill to occur in the Arctic region. Existing technologies for oil spill cleanup in ice-covered conditions are limited and there is a need for improved oil spill countermeasures for use under Arctic conditions. A recent field study has assessed a proposed oil spill response technique in ice-infested waters based on the application of fine minerals in a slurry with mixing by propeller-wash to promote the formation of oil-mineral aggregates (OMA). While it was verified in the experimental study that the dispersion was enhanced and mineral fine additions promoted habitat recovery by enhancing both the rate and extent of oil biodegradation, limited monitoring data provide little insights on the fate of dispersed oil after the response. To help understand the oil transport process following mineral treatment in ice-covered conditions, mathematical modeling was used in this study to simulate the transport of OMA and calculate the mass balances of the spilled oil. To study the effects of ice and minerals on the fate and transport, the result was compared with scenarios without ice and without the addition of mineral fines. The results show general agreement between the modeling results and field observations, and further confirm the effectiveness and potential for using mineral treatment as a new oil spill counter-measure technology. This technique offers several operational advantages for use under Arctic conditions, including reduced number of personnel required for its application, lack of need for waste disposal sites, and cost effectiveness.