ABSTRACT
Information on contaminant distributions in fractured rock is meagre because of the complexities of fracture networks and the practical limitations imposed by monitoring wells or other borehole groundwater sampling systems. In two boreholes (120 m deep) in fractured sandstone where TCE occurs, an alternative depth-discrete approach was applied using analyses of many rock core samples for TCE concentrations as well as removable multilevel-monitoring systems. The rock core analyses indicated numerous depth-discrete TCE migration pathways in each hole, many more than indicated by other identification methods, and supported the conceptual model for immiscible-phase disappearance and plume movement in an interconnected network of discrete fractures. The rock core analyses were essential for determining the maximum depth of DNAPL impact and hydraulic head profiles from the multilevel monitoring systems gave insight into the hydrogeologic controls on the TCE migration.
