The U.S. Army Corps of Engineers seeks a contractor to modify and construct river training structures in the Mississippi River near Herculaneum and Ste. Genevieve, Missouri. The work involves modifying 44 existing structures and building two new ones across two separate ten-mile river reaches, using only recycled stone from the modified sites. The project will be performed using traditional river marine construction equipment like floating plants and barge-mounted cranes. No new stone material is required.