ST. LOUIS — St. Louis-based Walton Construction is advancing construction for three Wal-Mart Supercenter projects in Missouri and Illinois. The firm began construction of a 180,954-square-foot Wal-Mart, located in Harrisburg, Ill., in November 2007, and is expecting completion by August. The firm is also building a Wal-Mart Supercenter in Jacksonville, Ill., which is scheduled for completion in February. Finally, the firm is expanding an existing Wal-Mart located in Chesterfield, Mo., into a 190,617-square-foot Supercenter. The project began this past fall and is scheduled to be complete in October. Wichita, Kan.-based Law/Kingdom is providing design services for the Chesterfield and Harrisburg projects, while The Benham Group is designing the Jacksonville project.