Our future resources, groundwater

Abstract

for site investigation, and how projects can benefit from early and ongoing peer reviews. The second case study explains difficulties in working on unique problems without an effective conceptual hydrogeologic model, the need to always be concerned about the quality of chemical data, and the need to be alert to behaviors that are beyond typical experience. Sudicky et al. (2008) present large-scale surface-subsurface hydrodynamic model that was applied to a 17 km 2 subcatchment of the Laurel Creek Watershed in Southern Ontario, Canada. A steady-state condition was achieved in the model by calibrating the subsurface flow field to 16 observation wells where long-term hydraulic head data were available. The model was then subjected to several hundred hours of rainfall data and the resulting discharge hydrographs were compared with the measured hydrographs. The calculated subsurface hydraulic head distribution and surficial rainfall-runoff responses, respectively, were shown to agree moderately well with those observed in the system during this period. These results suggested that the model is capable of reproducing surface and subsurface hydrodynamic processes at the subcatchment scale although the results could be better through improved parameterization of the subcatchment and the manner in which the model simulates evapotranspiration processes. Koo and Kim (2008) perform numerical simulations to demonstrate variability in local groundwater recharge in response to monsoon rainfall in Korea. Monsoon in the summer provides more than 50% of the total precipitation in Korea, thus important for recharge to shallow aquifers. This paper specifically examines impact of monsoon precipitation on the water flux and thermal diffusivity in the vadose zone and variability of precipitation recharge in relation to the monsoon rainfall by applying heat transport and infiltration models to 22-year time series soil temperature and meteorological data. The results demonstrate that the annual recharge is linearly proportional to the annual precipitation with varying degrees of the correlation coefficients depending on soil types. Nordstrom (2008) reports results of recent investigation to determine the pre-mining groundwater quality at a molybdenum mine in northern New Mexico, USA. The pre-mining groundwater quality was inferred by studying a