Acknowledgments ................................................. i
Abstract ...................................................... iii
Symbols ......................................................... v
1 Introduction ................................................. 1
1.1 State of the art ........................................ 1
1.2 Objective ............................................... 2
1.3 Dissertation organization ............................... 3
2 Hydrodynamics of the subsurface .............................. 5
2.1 Flow and mass transport in the vadose zone .............. 5
2.1.1 Darcy's law ...................................... 5
2.1.2 Richards' equation ............................... 6
2.1.3 Benchmark examples ............................... 9
2.2 Flow and mass transport in groundwater ................. 15
2.2.1 Groundwater flow equation ....................... 15
2.2.2 Mass advection-dispersion equation .............. 20
2.2.3 Benchmark examples .............................. 25
3 Workflow and implementation of the model .................... 49
3.1 Geometrical modeling ................................... 49
3.1.1 Borehole data preparation ....................... 49
3.1.2 Model boundary and primary TIN or 2-D mesh
definition ...................................... 50
3.1.3 3-D mesh generation with horizon method ......... 51
3.1.4 Interface between GMS and OGS ................... 53
3.2 Parameter estimation ................................... 53
3.2.1 Mathematical theory ............................. 54
3.2.2 PEST parameter estimation work flow with OGS .... 57
3.3 GeoHydroDataBase ....................................... 61
3.3.1 Designing a GHDB model with UML ................. 61
3.3.2 Filling GHDB with data .......................... 64
3.3.3 Interface between OGS and GHDB .................. 64
3.4 Visualization in 3-D Lab ............................... 68
4 Model applications .......................................... 69
4.1 Regional hydrological analysis of Meijiang catchment ... 69
4.1.1 Concept of the regional hydrologic soil/
groundwater model ............................... 70
4.1.2 Application of the RHSM concept to Meijiang
catchment ....................................... 75
4.1.3 Conclusion and future work ...................... 79
4.2 Groundwater drawdown at Nankou site of Beijing Plain ... 81
4.2.1 Introduction ......................................... 81
4.2.2 Study site and hydrogeologie setting ............ 85
4.2.3 Model development ............................... 87
4.2.4 Results and discussion .......................... 92
4.2.5 Conclusions and outlook ........................ 100
4.3 Groundwater quality deterioration at Nankou site ...... 102
4.3.1 Background ..................................... 102
4.3.2 Potential sources of groundwater pollution ..... 103
4.3.3 Hydrochemistry ................................. 106
4.3.4 Concept model: nitrogen transformations ........ 106
4.3.5 Groundwater model .............................. 110
4.3.6 Mass transport model ........................... 1ll
4.3.7 Pump and treat scenario analysis ............... 113
5 Summary and outlook ........................................ 119
A Publications list ........................................... 121
REFERENCES .................................................... 123
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