National Research Program
Quantitative Analysis of Heterogeneous Hydrologic Controls on Ground-Water Flow and Transport
Heterogeneous geologic material affects ground-water flow and transport on all scales. On the local scale, changes in hydraulic and geochemical properties can occur over distances on the order of centimeters. On the intermediate scale, the heterogeneity of intra-aquifer depositional layers in unconsolidated material and fractures in consolidated material influences the pathways of ground-water movement. On a regional scale, the heterogeneities due to areally extensive aquifers and confining units affect the flow system in a system wide manner that influences both the boundaries of the system and the generalized pathways of fluid movement in the system. An assessment of the importance of heterogeneity at all scales is required to better understand and define flow and transport in ground-water systems. In addition, the relationship of field measurements obtained in heterogeneous materials to the actual occurrence and movement of the water and chemical constituents in the system must be defined. The objective of this project is to quantify the effect of specific heterogeneous geologic controls on ground-water systems. Meeting the objective will entail the development of methods for incorporating the effects of heterogeneous hydrogeologic controls into simulations of ground-water systems. Ideally, the characterization and quantification of the heterogeneous earth material will incorporate basic geologic information on the deposition and history of the materials under study, as well as hydraulic and chemical information.
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