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Subsea release of oil from a riser: An ecological risk assessment


Nazir, M and Khan, FI and Amyotte, P and Sadiq, R, Subsea release of oil from a riser: An ecological risk assessment, Risk Analysis, 28, (5) pp. 1173-1196. ISSN 0272-4332 (2008) [Refereed Article]

DOI: doi:10.1111/j.1539-6924.2008.01136.x


This study illustrates a newly developed methodology, as a part of the U.S. EPA ecological risk assessment (ERA) framework, to predict exposure concentrations in a marine environment due to underwater release of oil and gas. It combines the hydrodynamics of underwater blowout, weathering algorithms, and multimedia fate and transport to measure the exposure concentration. Naphthalene and methane are used as surrogate compounds for oil and gas, respectively. Uncertainties are accounted for in multimedia input parameters in the analysis. The 95th percentile of the exposure concentration (EC 95%) is taken as the representative exposure concentration for the risk estimation. A bootstrapping method is utilized to characterize EC 95% and associated uncertainty. The toxicity data of 19 species available in the literature are used to calculate the 5th percentile of the predicted no observed effect concentration (PNEC5%) by employing the bootstrapping method. The risk is characterized by transforming the risk quotient (RQ), which is the ratio of EC95% to PNEC5%, into a cumulative risk distribution. This article describes a probabilistic basis for the ERA, which is essential from risk management and decision-making viewpoints. Two case studies of underwater oil and gas mixture release, and oil release with no gaseous mixture are used to show the systematic implementation of the methodology, elements of ERA, and the probabilistic method in assessing and characterizing the risk. © 2008 Society for Risk Analysis.

Item Details

Item Type:Refereed Article
Keywords:Ecological risk; Exposure analysis; Oil spill modeling; Risk assessment; Arsenic compounds; Chlorine compounds; Concentration (process); Environmental protection; Fluid dynamics; Fluid mechanics; Leakage (fluid); Methane; Naphthalene; Oil and gas
Research Division:Engineering
Research Group:Maritime engineering
Research Field:Ocean engineering
Objective Division:Mineral Resources (Excl. Energy Resources)
Objective Group:Environmentally sustainable mineral resource activities
Objective Field:Environmentally sustainable mineral resource activities not elsewhere classified
UTAS Author:Khan, FI (Professor Faisal Khan)
ID Code:94541
Year Published:2008
Web of Science® Times Cited:9
Deposited By:NC Maritime Engineering and Hydrodynamics
Deposited On:2014-09-11
Last Modified:2014-09-11

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