Integrated environmental risk assessment for petroleum-contaminated sites - A North American case study

Development of petroleum industries is associated with a number of environm ental concerns. Among them, soil and groundwater contamination by petroleum products is of major concern. In this study, an integrated risk assessment approach is proposed for evaluating environmental risks derived from petro leum-contaminated sites. The proposed approach is composed of (i) a hydroca rbon spill screening model (HSSM) which is used for simulating immisicible flow of released hydrocarbons in vadose zone, formation of lens in capillar y fringe, dissolution of pollutants at water table, and transport of the po llutants to receptors, and (ii) a fuzzy relation analysis (FRA) model which is developed for comprehensively evaluating risks caused by a number of po llutants with different impact characteristics, based on the HSSM results. This hybrid HSSM-FPA approach was applied to a case study for a petroleum-c ontaminated site in western Canada, where soil and groundwater was contamin ated by industrial wastes containing benzene, toluene, ethylbenzene and xyl enes (BTEXs). The results suggest that the HSSM-FRA can provide insight int o the potential risk to the receptor of concern downward the acquifer and c an serve as a basis for further remediation-related decision analysis. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.