Abstract: The disclosure is for an underground structure liner based upon an inflatable liner structure. An acid resistant layer is the innermost layer of an inflatable liner, and the liner is coated with epoxy resin on its outermost surface, the surface which contacts the existing walls of the underground structure. The outermost coated surface of the liner is constructed with a fibrous fleece layer for better retention of the epoxy and better adhesion of the epoxy to the walls of the underground structure. An added feature of the liner is a structure which also seals the liner to pipes entering the underground structure.