An Evaluation of Different Risk Ranking Systems

摘要

A number of risk ranking systems for contaminated sites have been developed by different jurisdictions. While the intent of each of these systems is similar, it is not clear whether they provide results that are comparable. In this paper, 20 contaminated sites are used to assess the United States’ Preliminary Assessment (PA) system, Sweden’s Methods for Inventories of Contaminated Sites (MICS) and New Zealand’s Risk Screening System (RSS) methods. The results were compared with each other and with Canada’s National Classification System for Contaminated Sites (NCSCS) as well as preliminary quantitative risk assessment (PQRA) results. The objectives were to determine if the systems yield similar recommendations regarding further actions, and to assess if there are acceptable correlations between different methods. The study concludes that PA, MICS and NCSCS methods can achieve similar conclusions, although there is a certain degree of inconsistency that is present, RSS can distinguish the very high and very low risk sites and, acceptable correlations exists among the methods except for PA and PQRA.