26. Fuzzy-Stochastic Risk Assessment Approach for the Management of Produced Water Discharges

In recent years, the large volumes of produced water discharges from offshore petroleum production activities have been identified to be an issue of concern by regulators and environmental groups. In the majority of the existing risk assessment research of produced water discharges, local environmental guidelines have been used as the evaluation criteria. However, these guidelines are mostly impractical and cannot be implemented. In this chapter, a fuzzy-stochastic risk assessment approach has been developed to predict the risks and to examine the uncertainties associated with produced water discharge and the related regulated values for the heavy metal, lead, in the marine environment. Specifically, the concept of fuzzy membership is established to reflect the suitability of local standards for produced water risk assessment. The Monte Carlo method has been used to address system uncertainties and provides stochastic simulation of pollutant dispersion associated with produced water discharges. The developed risk assessment approach is applied to an offshore petroleum facility located on the Grand Banks of Canada. As an extension of the previous risk assessment studies, the proposed approach will contribute to the development of effective decision tools for the assessment and management of produced water discharges in the marine environment.