Numerical Simulation of Tracer Tests in Heterogeneous Aquifer
نویسندگان
چکیده
A large-scale, natural-gradient tracer test in a heterogeneous aquifer at a site near Columbus, Miss. is simulated using three-dimensional (3D) hydraulic conductivity distributions derived from the borehole flowmeter test data. The simulated plume is more sensitive to the way the hydraulic conductivity field is interpolated from the measured data than it is to the dispersivity value. The transport model with longitudinal dispersivities in the range of 1-5 m can reasonably reproduce the observed plume to a certain concentration limit, but fails to reproduce the significant spreading of the tracer at diluted concentrations as observed in the field. This modeling study illustrates the formidable challenges in modeling and monitoring contaminant transport in very heterogeneous aquifers and points to the needs for new, innovative monitoring techniques that can be applied to characterize the spatial and temporal variabilities in the aquifer properties at scales suitable for detailed transport modeling.
منابع مشابه
760-766 Gw S-o 04
In hydrogeological investigations, the scale at which model parameters (e.g., hydraulic conductivity) are measured is usually quite different from the scale at which heads and contaminant concentrations are measured. The scale of grid blocks used in numerical simulations is usually different from the aforementioned two scales. However, measured concentrations and heads are used for calibration ...
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