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Preface
Summary
Dansk sammendrag
1 Introduction
2 Site description 2.1 Site of investigation and land use 2.2 Geology and hydrogeology of the site
3 Materials and methods 3.1 Boreholes and screens 3.2 Soil and groundwater sampling 3.2.1 Excavations and sampling of large undisturbed till columns 3.2.2 Soil sampling for chemical analyses 3.2.3 Groundwater sampling 3.2.4 Chemical analyses 3.3 Experimental set-up of undisturbed columns 3.4 Laboratory investigations of hydraulic conductivity and pesticide leaching 3.5 Pesticide adsorption experiments 3.6 Mapping of pesticide used in the project area
4 Results of investigations 4.1 Geological and hydrogeological investigations 4.1.1 The glacial sequence 4.1.2 Description of fractures 4.1.3 Groundwater levels and hydraulic gradients 4.1.4 Tritium profiles 4.1.5 Hydraulic laboratory experiments 4.1.6 Stability of fractures at depositional overburden 4.2 Pesticides in soil and groundwater 4.2.1 Degradation of pesticides 4.2.2 Pesticide adsorption on clay minerals 4.2.3 History of pesticide application 4.2.4 Pesticide monitoring at the point source site 4.2.5 Pesticide monitoring in the orchard 4.2.6 Residual pesticides in large undisturbed columns
5 Numerical modelling 5.1 Groundwater modelling 5.1.1 Computer Code 5.1.2 Conceptual Model 5.1.3 Model Area and Grid 5.1.4 Layers 5.1.5 Calibration Data 5.1.6 Boundary Conditions 5.1.7 Calibration 5.2 Modelling of undisturbed columns 5.3 Field scale numerical modelling of transport 5.3.1 Upscaling of fracture flow from columns 5.3.2 Modelling of tritium profiles 5.4 Sensitivity analyses 5.5 Determining criteria for modelling pesticide distribution by applying EPM flow versus fracture flow models
6 Conclusion
7 References
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