ABSTRACT
In North Rhine-Westphalia sinkholes are a more and more frequent phenomenon. Neumann has indicated that many of these sinkholes are connected to shallow mining or old mine shafts with an unstable filling. In 2000, complete trees and garages disappeared in two subsequent sinkholes in Bochum-Hontrop. Interventions in deep subsoil can have unforeseen effects on-surface. Mining is an industry of extremes: profits can be vast, but the risks involved can be huge too. Mining makes a substantial contribution to welfare in The Netherlands. The mining district eventually spanned across Zuid-Limburg, reaching from the German Aachen coalfields to the Belgian Campine basin. Modern coal mining used a different extraction method, one that was safer for mine workers underground. While coal mining involves the actual removal of rock from the ground, gas is withdrawn from the pores of its reservoir rock, without removal of the rock itself.
