The purpose of this Environmental Assessment (EA) is to address the effects of new construction proposed as part of navigation channel maintenance. Navigation channel maintenance includes periodic repair of existing training works or regulating structures, e.g., wing dams and closing dams, as well as modification of these structures. These actions generally involve large-grade limestone rock placement. Modification may include the raising, lowering, or notching of these structures to optimize their performance in flow control and sediment transport. Also, navigation dams and appurtenant structures require periodic rock placement for repair or improvement of bank protection.