A Possibilistic Analysis Approach for Assessing Environmental Risks from Drinking Groundwater at Petroleum-Contaminated Sites

Abstract

Subsurface contamination at petroleum-contaminated sites is posing a serious threat to the environment and the public and is acquiring more and more attention by governments and industries. This paper proposed a fuzzy risk assessment method and its application to a petroleum-contaminated site. The method consists of three parts: (i) calculation of fuzzy steady-state contaminant concentrations in the aquifer based on an analytical solute transport model, (ii) possibilistic analysis of fuzzy criteria for different risk levels, and (iii) environmental risk assessment based on the Euclidean method. The method can effectively reflect fuzzy natures of environmental quality at a site and evaluation criteria for different risk levels. Results of an illustrative case study indicate that environmental risks at a petroleum-contaminated site can be effectively evaluated through the developed methodology. The assessment results are useful for the related site remediation and management decision.

Keywords: Environmental risk assessment, fuzzy number, fuzzy set, petroleum contaminant, possibility, probability, uncertainty