In this article unless the context otherwise requires:
(1) The term "coal mine" means those operations in a coal seam which include the excavated and abandoned portions as well as the places actually being worked; also all underground workings and shafts, slopes, tunnels, and other ways and openings and all such shafts, slopes, tunnels and other openings in the course of being sunk or driven, together with all roads and facilities connected with them below the surface.