During the RERTR Conference in Chicago, Professor Hironobu Unesaki of Kyoto University, Jaci Dickerson of the U.S. DOE/NNSA, and Yann Guinard of AREVA hold mock samples showcasing AREVA’s approach to the fabrication of low enriched uranium fuel for the conversion of the Kyoto University Critical Assembly in Japan.

NNSA’s Office of Material Management and Minimization hosted the annual Reduced Enrichment for Research and Test Reactors (RERTR) International Meeting in Chicago last month, which focused on advancements in research reactor fuel development and the contributions that NNSA has made to the U.S. nuclear security mission.

This year marks an important milestone for NNSA’s nonproliferation mission: 100 nuclear reactors and medical isotope production facilities worldwide have either converted from highly enriched uranium (HEU) to low enriched uranium (LEU) or been verified as shut down.

Chicago Pile-1 (CP-1), the world’s first reactor, was built in 1942 in the West Stands section of Stagg Field at the University of Chicago. This year marks the 75th anniversary of the first controlled, self-sustaining nuclear chain reaction.“NNSA scientists and policymakers have supported and sustained the important role that research reactors play in modern science and technology while eliminating the threat posed by weapons-grade material at civilian sites,” said Pete Hanlon, NNSA’s assistant deputy administrator for the Office of Material Management and Minimization. “We’re seeking new frontiers in nuclear technology by qualifying new, first-of-their-kind LEU fuels for both reactor conversions as well as for future LEU reactors.”

The world’s first human-made, self-sustaining nuclear reaction was initiated in Chicago Pile-1 (CP-1) on December 2, 1942. Since then, research reactors have evolved quickly from CP-1. There is now a diverse reactor community that NNSA works with on conversions to fuel that cannot be used for an improvised nuclear weapon.

At RERTR, fuel fabrication company CERCA presented their development of innovative coatings for the LEU fuel to convert the Kyoto University Critical Assembly in Japan. By highlighting the 75th anniversary of the first research reactor in Chicago, NNSA celebrated both the birth of the nuclear reactor and the advances in nuclear science and technology that have allowed for the conversion of civilian facilities using HEU to LEU fuels and targets.

Early conversions were largely bilateral and achieved with existing LEU fuels. Today’s efforts often require multilateral collaboration and major fuel development efforts, which make these projects more complex. However, the RERTR conferences highlight the strong relationships in the research reactor community that are key to global HEU minimization efforts.

Conference attendees included scientists and policymakers from 14 countries and the IAEA, as well as representatives from across the Nuclear Security Enterprise, leaders from all U.S. High Performance Research Reactors, and international partners from research reactors and the nuclear industry.

Participants discussed technical progress, such as the development of new LEU fuels, the design and safety analyses for individual reactor conversions and the transportation and storage of LEU and HEU fuels. Additionally, NNSA and its partners were able to coordinate current and future conversion efforts with multiple foreign counterparts to advance the agency’s HEU-minimization mission.

RERTR 2017 highlighted the successful conversion of Ghana’s GHARR-1 reactor in July 2017.  Here, the LEU has been loaded into the core and reached criticality, with the reactor pool showing the blue glow of the Cherenkov radiation.