Effect of Climatic Change on Groundwater Quality Around the Subsurface Dam
Keywords:Limestone dissolution, Climatic change, Groundwater quality, Subsurface dam
The effect of climatic change on groundwater quality around subsurface dam area has been observed using numerical simulation. The study is related to sustainable groundwater development from subsurface dams constructed in the south islands of Japan where limestone is the underground geology. The model includes dispersion/diffusion, advection, ion exchange, formation of complexes in the aqueous phase, and the dissociation of water. The mass action, transport, and site action equations are expressed in a differential/algebraic form and solved by FEM. Results reveal that dissolution of limestone is proportional to the acidification of rainwater i.e. inversely proportional to the pH of rainwater. The resulting increase in calcium ion concentration is expected to block the filter of the pumping well and deteriorate the quality of groundwater as well. Again, dissolution of limestone is proportional to the increase of intensity of rain that leads to the increase of velocity of water. Dissolution of limestone was inversely proportional to the temperature.