REVISITING THE CONVERSION OF US NAVAL REACTORS TO LOW ENRICHED URANIUM

The use of Highly Enriched Uranium (HEU) in Naval Reactors continues to present a challenge to the nonproliferation regime. While no nation has yet chosen to take advantage of the “loophole” to the Treaty on the Non-proliferation of Nuclear Weapons (NPT), which allows diversion of nuclear materials for military uses like naval reactors, the June 2012 announcement by Iran of its intention to construct a nuclear submarine that would require HEU reminded the nonproliferation community of the need to consider alternatives to HEU fueled naval reactors. Furthermore, as fissile material minimization efforts continue to progress, including the proposed Fissile Material [Cutoff] Treaty (FMCT), the quantities of fissile material already reserved by nations such as the United States and Russia for their naval reactor programs will certainly present further challenges to progress in these efforts. As such, this report offers to revisit consideration of the use of Low Enriched Uranium (LEU) in U.S. Naval Reactors. In July 2012, the House Armed Services Committee requested that the Office of Naval Reactors conduct a review of that exact question. While the Director of the Office Naval Nuclear Propulsion (ONNP) considered the question in 1995 and concluded “ the use of LEU for cores in the U.S. nuclear powered warships offers no technical advantage to the Navy, provides no significant nonproliferation advantage, and is detrimental from environmental and cost perspectives,” much has improved in nuclear reactor technology since that report, including the successful implementation of LEU fuel in French naval reactors as well as several successful conversions of HEU research reactors to the use of LEU fuel. Of course, the technical and strategic requirements of U.S. Naval reactors, in particular submarine reactors, certainly differ from the successful conversions mentioned above. However, as the U.S. Navy is currently designing the SSBN(X) Ohio Class submarine replacement, there is no better time to revisit this important question. Therefore, this report endeavors to use the 1995 ONNP report as a baseline to revisit the issues presented therein with new consideration of recent technical developments, and determine whether the conclusions of the 1995 report still remain true today.