Karst is a significant aspect of Ireland’s hydrogeology as carboniferous limestones underlie more than half the area of the Republic. In a non-karst aquifer, most information about groundwater velocities, flow directions and aquifer storage can be obtained from pumping test data. In karstified aquifers these parameters are extremely difficult to determine by borehole analysis. Karst aquifers often contain open conduit flow paths with hydraulic characteristics more like surface streams than groundwater. Wells rarely penetrate the main conduits of a karst groundwater basin as conduits usually account for only a very small percentage of the aquifer but often contain most of the flow. To get a real idea of aquifer characteristics, especially for these heterogeneous, anisotropic conditions, a special method of investigation is used; water tracing. For more information click here.