Several times a year, a convoy including an unmarked truck and heavily-armed chase vehicles moves from a government plant in Oak Ridge, Tennessee, along major highways to others in Irwin, Tennessee, or Lynchburg, Virginia. Later, similar convoys with special guards move from those sites to naval bases in King’s Bay, Georgia, or Kitsap, Washington.
This is the nerve-wracking, but largely hidden dance of highly-enriched, weapons-usable uranium in the United States, a steady movement of nuclear explosive material along public routes from one protected government site to another, all to supply fuel for the reactors that power the U.S. Navy’s submarines and aircraft carriers.
The Navy has been relying on such highly-enriched uranium (HEU) shipments since 1953, when the first nuclear-powered vessel, the USS Nautilus had its reactor core installed. Although the shipments are constantly monitored and the trucks are equipped with counterterror measures, it’s a fraught experience for many of those involved. HEU is generally considered a choice target for terrorists, since it can be readily used to create a devastating nuclear explosive.
Now some experts are wondering: Does the U.S. Navy have to keep doing this? And if it does, will the Navy encourage military officials in other countries to do it as well –to build submarines and other vessels powered by nuclear reactors that consume HEU that has to be moved regularly from one place to another, rather than using a more benign fuel that cannot as readily fuel nuclear weapons?
The experts say the issue is on the table now because countries like Iran, Argentina and Pakistan are claiming they intend to build nuclear-powered submarines – and any policy change by the U.S. military would take years to implement.
A good way to reduce the terror risks posed by HEU would would be for the U.S. Navy to stop using it to power submarines and aircraft carriers and replace it with low-enriched uranium, which isn’t suitable for use in weapons, a group convened by the Federation of American Scientists said in a report released on March 19. For two decades, the Navy has refused this idea, insisting that the low-enriched fuel can’t match the superb performance of the HEU inside its shipborne reactors.
It’s clear that to satisfy the Navy’s concerns, engineers would need to develop compact new reactors capable of operating more efficiently than existing reactors when fueled by low-enriched uranium, said the group, which included a physicist, four nuclear engineers -- one of them a retired Navy vice admiral -- and three nuclear policy experts.
In a press conference in Washington, they recommended that the government begin a major effort to develop such a propulsion system next year, before an international summit meeting opens in Chicago in 2016, for the purpose of promoting nuclear security around the globe.
While it’s already too late for the Navy to convert to low-enriched uranium for use in the Ohio-class ballistic and cruise missile subs, scheduled to begin construction in 2021, it could potentially produce a new reactor in time for the next generation of attack submarines and aircraft carriers, scheduled for deployment in the 2030s and 2040s, if it starts the program in 2017, the group said.
The report said, moreover, that the United States is slowly but steadily using up its highly-enriched uranium set aside for naval nuclear fuels. By the 2060s, it said, the Navy will be faced a need to produce more of the weapons explosive, undercutting U.S. nonproliferation policy, unless it shifts gears.
If the United States resumes production, said Alan Kuperman, coordinator of the Nuclear Proliferation Prevention Project at the University of Texas and an author of the report, “we won’t have a leg to stand on when we tell other countries not to produce highly-enriched uranium.”
The report, “Naval Nuclear Propulsion: Assessing the Benefits and Risks,” was financed by the MacArthur Foundation, which has also funded work by the Center for Public Integrity.
Officials from the Office of Naval Reactors – a part of the Energy Department -- said in a report to Congress in January 2014, that substituting low-enriched for highly-enriched uranium would raise operating costs, cause more radiation exposure for crews and maintenance workers and generate more radioactive waste.
But the report also said “the potential exists” to develop a new generation of more efficient low-enriched uranium naval reactors that could address these concerns. A spokeswoman for the Naval Nuclear Propulsion Program said this week that the service could not immediately comment further.