ABSTRACT
An integrated interpretation of hydraulic data, test pumping and hydrogeochemical data demonstrates the value of combining several different methods for improved characterisation of a fractured-rock aquifer and assessment of recharge in a temperate climate environment. These methods were applied at the proposed open cut barite-silver mine, in Kempfield, central NSW, Australia. The test pumping results, hydraulic data, assessment of recharge rates, baseflow and geochemical analysis guided the construction of three-dimensional numerical model of groundwater flow to understand the groundwater system. There are no published groundwater studies in this area; hence the analysis in this paper is based on the data collected mainly from the site investigations. The integrated field study of structural pattern and hydraulic tests shows that structural lineaments and fracture porosity are important features that affect groundwater flow in a fractured rock aquifer. The recharge rates have been assessed indirectly using both chloride mass balance and hydrograph analysis, with results favoring the chloride mass balance method. Groundwater-surface water connectivity is limited with an estimated baseflow contribution of 1-7% of streamflow.
