A stage assembly includes a workpiece table that supports the workpiece adjacent to an optical assembly. An environmental system supplies and removes immersion liquid to and from a space between the workpiece and the optical assembly to form an immersion area. The environmental system has a lower surface disposed opposite from an upper surface of the workpiece and/or the workpiece table. The lower surface is spaced a first distance from the workpiece and/or the workpiece table to form a meniscus at a periphery of the immersion area. An edge member is provided on the environmental system and extends past the lower surface of the environmental system so that a lower portion of the edge member is spaced a second distance, smaller than the first distance, from the upper surface of the workpiece and/or the workpiece table at a position beyond the periphery of the immersion area.