Résumé :
|
An evaluation of the hydraulic conductivity of a compacted clay liner was conducted on an extensively at 250 evenly spaced points. Spatial variability of soil, water content, and density was high even though average values were close to design specifications. Inflow, outflow, and density changes were monitored during the one-year ponding time of the study. Data indicate that both water and tracer solutes moved considerably faster than expected, indicating that only a small fraction of total pore space was active. Although data from soil core samples and nuclear surface moisture-density probes adequately described spatial distribution of water and density within the compacted clay, neither water content nor density was correlated with the spatially distributed hydraulic conductivity. Both dye and tracer studies confirmed rapid transport through a network of preferential flow pathways.
|