Mineshafts are obvious hazards and in addition to their depth, may be full of water (Plates 1.0 and 2.0).Some mineshafts can take the form of ponds at the surface (Plate 2.0).Mine adits (horizontal tunnels from the surface, or side of a hill for access or drainage), while less obviously a source of danger, have hazards such as collapses, becoming lost, sudden drops, internal shafts and ???bad air?