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The article discusses a numerical model for estimating groundwater flux from subsurface temperature profiles obtained from field measurements. The authors explain that their model utilizes the MacCormack scheme which is based on the Finite Difference Method (FDM) for solving the governing partial differential equation of convection. Numerical solutions obtained for the study area located in the Nagoka plain in Japan are compared with published measured data acquired by others. Results concluded good agreements and fit the previously observed data with a correlation coefficient of 0-88.

A geochemical study was carried out in a small spa area (Onyang Spa, Korea) where intensive pumping of deep thermal groundwater (1 300 000 m3 year-1) is taking place. This has caused the deep fractures to lose their artesian pressure and the upper shallow fractures have been encroached by shallow, cold waters. To quantify the influence of long-term heavy pumping on the quality of the geothermal water, groundwater sampling and chemical analysis, water-level measurement, and well loggings were performed for the selected deep thermal wells and shallow cold wells. Chemical analysis results indicate a big contrast in water chemistry and origins between the two water types. Shallow groundwater shows a wider concentration ranges in solutes that are closely related to human activity, illustrating the water's vulnerability to contamination near the land surface. Plots of water chemistry as a function of fluoride reveal that the quality of the thermal water was greatly influenced by the shallow, cold groundwater and that intensive pumping of the deep thermal groundwater has caused the introduction of shallow groundwater into the deeper fractures. Although the deep and the shallow fractures were piezometrically separated to some extent, a mixing model based on fluoride and nitrate indicated that the cold-water fractions in the thermal wells are up to 50%. This suggests that the thermal water is faced with water quality degradation by the downward flow of the shallow, cold water. Restriction on the total of all the pumpage permits per unit area is suggested to restore the artesian pressure of the deep thermal aquifer and to prevent cold-water intrusion in the study area. Copyright 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In order to consider a counterplan to preserve an ancient royal tomb in Kongju, Korea, the deformation of the wall structure, the atmospheric temperature in the tomb, and the groundwater level have been monitored. The long-term measurement of biaxial tilting of the tomb walls revealed that the brick-built subsurface opening had been subjected to severe structural instability. The measured deformation of the tomb was consistent with the displacement of soil around the tomb calculated using a numerical analysis. The instability of the tomb structure is closely related to the rainy season as the deformations measured are several times that in the dry season. A sudden change of temperature inside the tomb exerted an influence on the deformation of the tomb structure as well. It is suggested that the excavation be restored for tourists, the quicklime layer for preventing groundwater infiltration is reinforced, and a constant temperature is kept inside the tomb. [ABSTRACT FROM AUTHOR]

Geotechnical and hydrogeological investigations were conducted as a basis for methods to conserve the Muryong Royal Tomb, one of the most significant Korean cultural properties. First, long-term monitoring of wall-structure movement using the tilt-meter system examined the structural stability of the tomb. Second, an artificial recharge test was performed to analyze the major seepage pathway observed inside the tomb during the rainy season. Measured movements of the wall structure indicate that the tomb has a structural safety problem, caused by a front chamber constructed following excavation. The recharge test and its numerical simulations showed that the major seepage source is the downward flow of water in the unsaturated zone through cracks in the protective layer above the tomb. A plan conservation suggests refilling the front chamber of the tomb to reestablish the original state prior to excavation and to reinforce the protective layer by an effective waterproof material. [ABSTRACT FROM AUTHOR]