Slovenia's main military training area at Poček is located in the mountainous Javorniki Watershed. This is a karstic district without surface drainage or river valleys. The typical landscapes are conical hills and plateaus with many dolines. The lithology, tectonic structure and speleological data indicate a typical karst aquifer with underground water moving rapidly through fissures and conduits. Little attenuation occurs in such conditions and as a result there is a high risk of pollution. Tracer tests have shown that a significant proportion of the water recharging the Malni and Vipava springs comes from the vicinity of the military training area. As a result any polluting activities taking place within the military training area are likely to affect the two springs. This is a very serious matter as the springs have been developed to provide the water supply for the population of south-western Slovenia.