Modelling and measuring the weathering and bioavailability of fuel spills in polar marine environments, and assessment of the applicability of fuel dispersants

• Main Author: Konstantinos Kotzakoulakis
• Format: Thesis
• Language: unknown
• Published: 2017
• Subjects: Other education not elsewhere classified; dispersant; modelling; bioavailability; oil spill; Dispersing agents > Effectiveness; Dispersing agents; Oil spills; Oil spills > Antarctical; polar marine environment; fuel spill; weathering; Antarctic; The Antarctic; Australian Antarctic Territory; Deception Island; Ifo; Antarc*; Antarctica; Nordkapp
• Online Access: https://doi.org/10.25949/19428263.v1; https://figshare.com/articles/thesis/Modelling_and_measuring_the_weathering_and_bioavailability_of_fuel_spills_in_polar_marine_environments_and_assessment_of_the_applicability_of_fuel_dispersants/19428263

Shipping activity is increasing continuously in Antarctica in the last couple of decades. During the 2014/2015 summer season 191 tourist expeditions visited Antarctica carrying 36,702 passengers in addition to the illegal fishing activity and shipping related to research station support operations. Recent incidents such as the stranding of Akademik Shokalskiy on 25 December 2013, the grounding of the MS Nordkapp at Deception Island on 30 January 2007 and the fire aboard the Nisshin Maru in February 2007, which was carrying approximately 1000 tonnes of heavy fuel oil, have highlighted the risk of a major fuel spill in the Antarctic waters. Currently, much needed data on the behaviour of these fuels in the Antarctic marine environment in order to plan response measures is missing. The three fuels that are used in the Australian Antarctic Territory are the Special Antarctic Blend (SAB), the Marine Gas Oil (MGO) and the Intermediate Fuel Oil 180 (IFO-180). During this study we examined the rate of weathering and the path to bioavailability of these fuels to the Antarctic marine biota. The main mechanism of weathering for SAB and MGO in the Antarctic marine environment is evaporation with 80% of SAB and 33% of MGO evaporated in 6 days and 30 days respectively. Both SAB and MGO are pure distillates consisting of hydrocarbons in the range of C10-C15 and C7-C26 respectively which explains the fast evaporation rate. IFO-180 is a heavy fuel consisting of around 90% residual distillation fuel (Bunker C) and less than 10% light distillate. It was found that the loss from evaporation during the first 30 days is 7% which corresponds to the majority of the added distillate and then evaporation almost stops. These results show that the majority of both MGO and IFO can persist in the Antarctic marine environment for long periods of time and response measures such as mechanical recovery or treatment methods need to be considered. The main path to bioavailability of these fuels is through dissolution in the seawater column. For ...