Environmental disasters can maliciously affect the property, human lives and entire ecosystems. The magnitude and extent of such a disaster can lead to uncertainty about the measurement and the extent of liability, and how the restoration of the environmental damage will be achieved. Oil spills from tanker vessels constitute the most severe threat to the local and global ecosystem in the shipping industry. when an oil spill incident emerges, it usually spreads rapidly, leading to massive disasters in the local aquatic ecosystem and human property without prompt treatment. This paper assesses the famous accident of Exxon Valdez: (i) to identify and measure the effect of each contributing factor to the accident, (ii) to determine the best solutions to minimise such risks in the future with the implementation of failure mode effect analysis in conjunction with the doctrinal method and at the same time (iii) to propose a new method of accident assessment by combining the doctrinal method with a variation of a well-known risk assessment method.