In Denmark, a landslide of contaminated soil could become a slow-moving environmental disaster. Near the city of Randers, a large mound of soil containing heavy metals and oil products broke out from a waste reprocessing plant and is heading in the direction of a village. It’s also raising concerns about water contamination. The World’s Carolyn Beeler spoke to Kristian Svennevig. He’s a senior researcher at the Geological Survey of Denmark and Greenland who studies landslides.