Risk classification of contaminated sites - Comparison of the Swedish and the German method

To classify contaminated sites into different risk classes, many different methods exist in Europe and worldwide. However, no systematic comparison of European risk classification methods has been carried out so far to carve out the advantages and disadvantages of the methods and to homogenize them. To address this research gap, this study aims at comparing the Swedish Method for Inventories of Contaminated Sites (MIFO) with the German Individual Assessment of Contaminated Sites Method (EB) from the Hessian Agency for Nature Conservation, Environment and Geology (HLNUG) regarding the risk class categorization of 51 contaminated sites. The results revealed that with the MIFO 39% fewer contaminated sites are assigned to risk classes 1 and 2 and thus, subject to remediation compared to the EB. Moreover, in comparison to the EB, the MIFO showed a lower comparability, traceability, and a larger room for interpretation, which could be related to the lack of a quantitative approach such as a point or ranking system in the MIFO. Hence, we recommend providing the MIFO and other methods that lack a quantitative approach with a point and/or ranking system, similar to the EB, to increase their objectivity for the risk class categorization of contaminated sites.