The invention relates to a geomembrane lining system and method of assembly in which a protective release seal is provided on the weld edges of a geomembrane liner. Geomembrane liners are arranged to line a containment area. Adjacent liners are arranged to partially overlap one another. The side edge of the geomembrane liner have a protective release film over areas of the liners that are to be welded. The protective release film protects the weld edge from accumulating dust and debris prior to and during installation. Dust and debris may disrupt the weld seam and allow contained waste material to leach into the surrounding area. The protective release film is removed prior to or during a welding operation. As a result, the adjacent geomembrane liners are welded together while minimizing or eliminating the presence of dust and debris at the weld edge.