Solute dispersion along unsteady groundwater flow in a semi-infinite aquifer

摘要

Analytical and numerical solutions are obtained fordispersion of pollutants along unsteady groundwater flow in a longitudinal directionthrough semi-infinite aquifers the permeability of which is either uniform or varies withposition. Sources of pollution are both a concentrated point input at the origin and aspatially distributed background source. One expression chosen to represent the seasonalpattern of the time dependent velocity is sinusoidal behaviour over a year. The solutionsobtained predict the time and distance from the location at which an input concentrationis introduced at which the pollution concentration becomes harmless. Also, the time periodfor rehabilitating a polluted aquifer for human use can also be assessed.