A barrier wall configured for formation and placement within a formed trench. The barrier wall is formed from a plurality of wall segments. Each wall segment comprises a wall body, a length coupling subassembly and a width coupling subassembly. The wall body includes a front surface and a back surface. The length coupling subassembly is coupled to the wall body. The width coupling subassembly coupled to the wall body. The plurality of wall segments can be attached to each other by joining at least one of the length coupling subassembly of one of the plurality of wall segments to another one of the plurality of wall segments, and the width coupling subassembly of one of the plurality of wall segments to another one of the plurality of wall segments.