Watch the Signing Ceremony for the Manhattan Project National Historic Park with Sally Jewell, U.S. Secretary of the Interior; Ernest Moniz, U.S. Secretary of Energy; Jon Jarvis, Director National Park Service; Lamar Alexander, U.S. Senator, Tennessee; Maria Cantwell, U.S. Senator, Washington; Tom Udall, U.S. Senator, New Mexico; Martin Heinrich, U.S. Senator, New Mexico; and Vic Knox, Associate Director of Park Planning, National Park Service.