| Abstract: | A methodology for calculating strains that accompany mining is used to estimate the post-mining modification of the hydraulic conductivity field and the change in the regional and local subsurface water system. The techniques yield reasonable agreement with recorded changes in water levels for reasonable and defensible choices of material parameters in validation exercises at an instrumented longwall site. Water level changes recorded above the twin panel longwall configuration are complex and varied. However, they may be explained through consideration of the mining-modified conductivity field alone. Changes in hydraulic conductivity are independently corroborated from the results of in situ permeability tests, conducted before and after mining, that confirm the overall influence of mining-induced strains. These resulting patterns of hydraulic conductivity enhancement enable direct explanation of observed water level changes. © 1997 John Wiley & Sons, Ltd. |
