Thinking on Assessment Framework of Stabilization Effect for Heavy Metals Contaminated Soil Based on Disposal Scenarios and Risks

Domestic and international standard methods were reviewed and the existing problems pointed out on assessment of stabilization effect for heavy metals contaminated soil. At present, the method of toxicity leaching under the simulated scenarios of landfilling and acid rain is mostly adopted for the assessment. However, this assessment method cannot completely simulate the release of pollutants into the surrounding environment for different purposes, such as gardening soil, road construction, embankment, etc. It is also difficult to characterize the release risk of heavy metals under the long-term effects of the actual complex environments such as carbonization and freeze-thaw, etc. The appropriate leaching methods should be established based on different reuse and disposal scenarios of the stabilized soil, to assess the possibility and amount of heavy metals release under different environmental stress conditions. The health and ecological risk assessment methods should be built up to evaluate the potential risk of the stabilized soil. Through these attempts, the framework of leaching and risk assessment methods for the stabilized soil could be formed.