Ground-water intrusions in a mine beneath Høganesbreen, Svalbard: Assessing the possibility of evacuating water subglacially

Abstract

Evacuation of the ground-water intruding into a coal mine beneath Hoganesbreen, Svalbard, is difficult and expensive. To solve this problem, it was proposed that the mine be connected to the ice-bedrock interface. Pumping hot water from the mine should establish a flow path along the glacier bed where the ground-water would drain gravitationally. In this paper, we assess the requirements for maintaining such a drainage system in open-channel conditions. To obtain the bedrock topography, we determined the ice thickness by ground-penetrating radar and subtracted it from the surface elevation measured by global positioning system. A measured temperature profile at the site where the mine should connect to the glacier bed (140 m depth) revealed that the basal ice is below the pressure-melting point. The locations of major subglacial conduits were estimated using a hydraulic-potential approach. We adopted a model of time-dependent discharge through a Röthlisberger channel to calculate a set of scenarios using different flow-law parameters. Results of the simulations suggest that for the given conditions, water flow would be pressurized, thereby inhibiting the gravitational drainage of the mine. © International Glaciological Society.