AIKEN, S.C. - The Savannah River Site ’s (SRS) recently began dissolving spent nuclear fuel (SNF) from the High Flux Isotope Reactor (HFIR) at the Oak Ridge National Laboratory (ORNL) in eastern Tennessee.
“This campaign marks the first time H Canyon has dissolved HFIR SNF since 1988, and is essential for the continued mission of HFIR," DOE-Savannah River Nuclear Materials Programs Manager Maxcine Maxted said.
L Area currently stores 120 HFIR cores, which is the maximum capacity for HFIR storage. ORNL will reach its maximum capacity for storing HFIR fuel in fiscal year 2020. To ensure sufficient SNF storage for the HFIR reactor to continue its mission, DOE directed SRS to dissolve HFIR beginning this year.
“This campaign is also significant in that it marks the first time that there have been three different uranium streams feeding H Canyon simultaneously," Maxted said. “In addition to HFIR, the other streams are Material Test Reactor spent nuclear fuel and Target Residue Material. Multiple uranium streams allow for better utilization of the canyon capabilities."
The HFIR reactor is the highest flux reactor-based source of neutrons for research in the United States utilizing highly enriched uranium. The fuel elements, inner and outer elements, together form a reactor “core." After these cores are used, they are stored at ORNL for eventual shipment to SRS for processing.
Once the cores arrive at SRS they are stored in the L Area spent fuel basin underwater to reduce radiation rates while awaiting processing in H Canyon. The HFIR reactor at ORNL operates in support of its neutron scattering and isotope production mission, and SRS will continue to receive fuel cores to support its operation.
H Canyon’s mission is to blend down highly enriched uranium (HEU) SNF from domestic and foreign research reactor fuel into low enriched uranium (LEU). LEU can be used to make fuel for commercial power reactors and also makes the HEU non-proliferable.
To begin the chemical processing that turns HEU SNF into LEU, H Canyon reconfigured one dissolver and replaced the second dissolver that contained a failed cooling coil last year. Preparation for the HFIR mission also included revising the safety analysis and procedures, training of personnel, and a lot of practice in both H Canyon and L Area.
“It took a lot of hard work and dedication to prepare for this campaign," Maxted said. “However, we knew that the employees of L Area and H Canyon, the only hardened radiochemical separations facility operating in the United States, were up to the task. H Canyon is once again proving that it is a crucial element in enabling other DOE research facilities, such as the DOE national laboratory at Oak Ridge, to continue operation. It is this kind of collaboration that makes the DOE complex effective."
Source: U.S. Dept. of Energy, Office of Environmental Management
