Many contaminants disposed on or immited into soil are highly reactive. In order to understand, quantify, and predict contaminant movement through soil, descriptions of the chemical processes in soil have been combined with transport models. However, despite unambiguous evidence concerning the variability of soil in the horizontal plane, with regard to e.g. the mineral and chemical composition and physical properties, few models were formulated to take such heterogeneity into account. For a proper risk analysis of the hazards of contamination for soil and groundwater it is important that spatial variability of the soil system is considered explicitly.In this contribution we show how spatial variability of soil properties may be quantified such, that it may be incorporated in risk analysis. With emphasis to heavy metals and phosphate, we give an impression of simple sorption functions, that are stochastic functions of distributed soil parameters, such as organic carbon content, pH, etc. By introducing these functions in the governing transport equations it is possible to evaluate the mean behaviour of a soil system, that exhibits pronounced spatial variability. For particular cases a very simple analytical approximation is developed. Leaching of Cu, Cd, and P is treated as an example, and we give quantitative evidence of the variability of soil properties controlling these leaching processes. As the method proposed is simple, and applicable to other contaminants as well (radionuclides, pesticides) it represents a powerfull tool for risk analysis.
Weitere Kapitel dieses Buchs durch Wischen aufrufen
- Transport of Heavy Metals and Phosphate in Heterogeneous Soils
S. E. A. T. M. van der Zee
W. H. van Riemsdijk
F. A. M. de Haan
- Springer Netherlands
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