Abstract: A method for constructing a plastic lined concrete tank includes the forming of a plurality of plastic lined concrete panels. Each of the panels is made up of a concrete slab and a plastic sheet. The concrete slabs have opposed, laterally spaced, elongated edges and an inner surface and the plastic sheet each have a plurality of anchoring projections protruding outwardly from a face thereof. The panels are formed in such a way that the face of each plastic sheet is engaged against the surface of a corresponding concrete slab with the anchoring projections embedded in the concrete of said corresponding slab. The plastic sheets are arranged, configured and positioned such that a respective edge flap portion thereof projects outwardly beyond each edge of the corresponding slab and each such edge flap portion has an outboard segment.