Brian Bradley
NS&D Monitor
11/6/2015
Tritium production is the National Nuclear Security Administration’s “most pressing defense mission need,” according to the recently released “Tritium and Enriched Uranium Management Plan Through 2060” from the Energy Department. Tritium for use in the NNSA’s weapons program is produced by burning unencumbered low-enriched uranium at the Tennessee Valley Authority’s Watts Bar nuclear plant. The gas, which is used to boost the yield of a nuclear explosion, is captured when the LEU is irradiated and then sent to the Savannah River Site for processing. Unobligated LEU fuel for tritium production was projected to be expended by 2027, but the report says the unobligated LEU fuel need date for tritium production could reasonably be extended until 2038-2041 or later, if NNSA makes certain decisions.
Namely, the report suggests NNSA can push back the tritium need date to that time frame through several options, including three short-term actions: preserving existing unobligated LEU inventories, repurposing excess uranium, and down-blending national security and excess highly enriched uranium. “Based on long-range processing and capability assessments, current and future recycle and recovery capabilities and capacity are insufficient to process the materials in this backlog for many decades, even considering Y-12’s forecast transition to the new Uranium Processing Facility,” the report states.
Preserving the existing LEU would require DOE to contract through TVA for companies to maintain the unobligated status of LEU reserves until the material can be used in tritium reactors. Plans are under way between DOE and Energy Northwest to retain the unobligated status of 47 metric tons of depleted uranium slated for fabrication into nuclear fuel. The 47 metric tons would provide approximately one reload for a tritium production reactor, which would yield one additional year of tritium production at low cost and risk, the report states. Additionally, DOE is also working with TVA and Westinghouse, which has 43 metric tons of unobligated uranium, to keep that material’s obligation designation. This amount would be enough for one reactor reload during tritium production, and would extend tritium production one more year, until 2029, also at low cost and risk, according to the report. TVA also has in its reserves 1.5 single reloads of unobligated LEU, which could be used directly in a TVA tritium-producing reactor and draw out tritium production to 2030 at low cost and risk, notes the report.
The Department of Energy is also implementing a new down-blending program, the Repurposed Excess Uranium Program, which is intended to down-blend 13.4 megatons of excess HEU. A contract for only the first 3 megatons of HEU planned for the REU Program has been signed, because of “contracting difficulties,” and the blend-down will yield 64 megatons of LEU, about 50 of which would be unencumbered according to the report. Down-blending the remaining 10.4 megatons—which would yield about 215 megatons of LEU—has been difficult to organize, mainly because of a barter arrangement, which would essentially use LEU stocks as payment for down-blending. “While this has worked well for the previous down-blending campaigns, declining market values for[enriched uranium] over the last four years has reduced industry’s interest in being compensated for services with a portion of the derived LEU,” the report states. In lieu of bartering, DOE could appropriate funds, which would cost NNSA about $373 million but would secure agency ownership of the entire 215-megaton resulting stock, about 160 megatons of which would be unencumbered. The agency would pay roughly $1,674 per kilogram of uranium, $53 per kilogram less than the current market price, according to the report. If all 13.4 megatons of excess uranium can be repurposed, the resulting substance could provide five reactor reloads, extending tritium production until 2033 with a low relative cost to DOE, but at a moderate risk, partly because the action would require a contract and a resolution to the barter-versus-cash dilemma.
In addition to using civilian-derived LEU stocks to produce tritium, the report presents the option of down-blending national security and excess HEU, which would yield more than 400 megatons of LEU. This could provide 10 reactor reloads, or fuel for eight years of continuous tritium production by two reactors, potentially extending tritium production until 2041 at a moderate relative cost and risk to DOE.
American Centrifuge
The tritium report apparently informed DOE’s decision to shutter the Piketon, Ohio, piece of the American Centrifuge program, after the project was initiated, in part, to meet anticipated U.S. demand for the material. Ohio Sen. Rob Portman (R) blasted Energy Secretary Ernest Moniz during a Senate Energy and Natural Resources Committee hearing last month for sending the document to Congress this fall, after lawmakers expected its arrival in April. “You said you’d only do it after issuing a report that was due to Congress in April,” Portman said during the Oct. 6 hearing. “You never gave us the report. I got the report last night, after you already made your decision two weeks ago without informing us. We had to hear about it from the press.”
Several congressional lawmakers, mainly members of the Ohio delegation, have questioned DOE leadership in recent hearings why it was shutting down the Piketon, Ohio, piece of ACP. Moniz has emphasized that the department is not pulling the plug on ACP technology, but is moving all operations to Oak Ridge, Tenn., because continuing to spin centrifuges at Piketon would not provide any more technical knowledge on the technology.
“Scrubbing really hard on the need for enriched uranium using American-origin technology, we were able to extend the time frame…very, very dramatically,” Moniz said during the Oct. 6 hearing. “Secondly, the technical judgment made is that continuing to spin the machines will not give us any more technical knowledge on the technology that we will preserve.”
