Contaminant transport in shallow free surface aquifers

A large number of sites in the Czech Republic have been contaminated due to non-ecological disposal of industrial waste during the last forty years. These so-called old economic loads are necessary to be gradually eliminated. As remediation measures to be applied at the respective sites demand considerable costs, for each particular case such a remediation technology has to be selected to ensure not only reaching the remediation targets, but also economic efficiency.

Numerical simulation of solute transport requires good approximation of aquifer geometric shape. Therefore, the exploitation of quasi-spatial numerical model need not be adequate while modelling solute transport in a shallow aquifer with a extensive variable thickness. Using a three-dimensional model in such case will allow reliable setting of the contaminant propagation within the aquifer.

The example of contamination of a waste repository and a shallow aquifer with a free surface illustrates the advantages of the solute transport numerical modelling application in the very first stage of remediation planning, when not all data is available in the satisfactory amount, yet it is necessary to get an idea of the current condition of the aquifer contamination and its further development. It demonstrates the effect of the contamination water yield and the promptness of corresponding remediation intervention. Compatible hardware and software will make it possible to assess, in a short time and with low costs, the relevant remediation alternatives and evaluate the effect of interaction of the solutes transported by groundwater with the percolated medium.

• INTRODUCTION

• NUMERICAL MODELLING OF GROUNDWATER FLOW

• MODELLING OF SOLUTE TRANSPORT

• SIMULATION OF SOLUTE TRANSPORT IN A SHALLOW AQUIFER

• CONCLUSIONS

• ACKNOWLEDGEMENTS

• REFERENCES