https://ingalls.huntingtoningalls.com
"Ingalls Shipbuilding is located in Pascagoula, Miss. on 800 acres of land along the Pascagoula River. Employing 11,500 employees, Ingalls is the largest manufacturing employer in Mississippi and a major contributor to the economic growth of Mississippi and Alabama. Ingalls is the largest supplier of U.S. Navy surface combatants, and has built nearly 70 percent of the U.S. Navy fleet of warships".
That is no small or insignificant shipyard.
The Soviets would have been very interested in what was going on there, so possible Cold War goings-on, and then there is the possibility of a chemical spill spreading intoxicating/incapacitating fumes and the clean-up team wearing NBC suits...?