US develops LEU fuel for research reactors

5 January 2018

The US National Nuclear Security Administration (NNSA) on 21 December submitted to the US Nuclear Regulatory Commission (NRC) a preliminary report on uranium-molybdenum (U-Mo) monolithic fuel that will enable the conversion of six US research reactors from highly enriched uranium (HEU) to low-enriched uranium (LEU). The report contains data on the performance of the fuel in a reactor under a variety of conditions.

The US high-performance research reactors awaiting conversion include:

  • the Advanced Test Reactor and the Advanced Test Reactor Critical Assembly, both at Idaho National Laboratory;
  • the High Flux Isotope Reactor at Oak Ridge National Laboratory; the Massachusetts Institute of Technology Reactor (MITR);
  • the National Bureau of Standards Reactor in Maryland; and
  • the University of Missouri Research Reactor.

MITR, a light-water-cooled and moderated, heavy-water reflected reactor, currently uses fuel enriched to 93%. Conversion of MITR will eliminate the transit of about 3kg of HEU fuel a year, according to NNSA. The preliminary safety analysis report submitted to the NRC shows that the MITR can safely operate using the new LEU fuel. Based on feedback from the NRC review of the report and the ongoing tests of the LEU fuel, MIT will submit a final safety analysis report. Following NRC approval, conversion of MITR to the qualified LEU fuel will begin.



Privacy Policy
We have updated our privacy policy. In the latest update it explains what cookies are and how we use them on our site. To learn more about cookies and their benefits, please view our privacy policy. Please be aware that parts of this site will not function correctly if you disable cookies. By continuing to use this site, you consent to our use of cookies in accordance with our privacy policy unless you have disabled them.