Justin Callahan, project manager, U.S. Army Corps of Engineers, walks over crusted soil in the crust management area of the Paul S. Sarbanes Ecosystem Restoration Project at Poplar Island in the Chesapeake Bay near Talbot County, Maryland, July 12, 2012. Crust management is one of several steps to "building" a marsh. (Mary F. Calvert/MCT) (MARY F. CALVERT/MCT)