The company that operated the American Centrifuge Lead Cascade Facility, Centrus, began the process of decommissioning the facility. The U.S. Nuclear Regulatory Commission received a license amendment application and initiated a public review of the decommissioning plan.

The cascade began operations in March 2010 and was shut down in 2015. The American Centrifuge Project, of which this cascade was a part, was terminated in 2016.

Ukraine's generating company Energoatom signed a contract with France's Orano (formerly Areva) "for assessing the feasibility of reprocessing services of spent fuel assemblies of Ukrainian VVER-1000 nuclear reactors in La Hague facility."

The contract is part of Ukraine's effort to diversify its nuclear fuel cycle. Ukraine is constructing a spent fuel storage facility and is working with Westinghouse to use its fresh fuel.

China National Nuclear Corporation (CNNC) announced that it completed a "large-scale demonstration project for a new generation of uranium enrichment centrifuges." According to the company statement, the centrifuges are independently researched and developed by CNNC, which owns independent intellectual property rights. The centrifuges have been added to the Hanzhong enrichment facility in Shaanxi province.

The Hanzhong plant hosts four enrichment facilities with the total capacity of 1.5 million SWU/year that use centrifuges supplied by Russia. In addition, China was reported to deploy a 0.5 million SWU/year facility with centrifuges that are believed to use the Russian technology. It began operations in 2011. The most recent estimate suggests that the total capacity installed in Hanzhong at the end of 2017 was 2.0 million SWU/year. Now that the new facility began operations, it may significantly increase the full capacity of the plant.

The National Research Universal (NRU) research reactor, operated by the Canadian Nuclear Laboratories (CNL) at Chalk River was shut down on March 31, 2018. The decision to shut down the reactor was made by the government of Canada in February 2015. While announcing its intent to close the reactor, the government approved its operations in standby mode since 31 October 2016 "to help support global medical isotope demand between 2016 and 2018 in the unexpected circumstances of shortages."

Frank von Hippel

The U.S. Department of Energy (DOE) has launched an initiative to build and begin operating by 2038 a new small-capacity national military uranium enrichment plant. Its initial mission would be to produce low-enriched uranium (LEU) to fuel two Tennessee Valley Authority nuclear power reactors that produce tritium for U.S. warheads as a byproduct. DOE's cost range estimate for the new facility is $3.1-11.3 billion.

US nuclear weapons rely on several grams of tritium each to boost more than ten-fold the yields of their primary fission "triggers". The boosted primary explosion drives the fission-fusion secondary stage that releases most of the total yield of one hundred kilotons or more of these weapons. The tritium must be replenished since it decays with a half-life of 12.3 years.

The Tennessee Valley Authority operates a power reactor (soon two) to make tritium in lithium-6 containing rods inserted into the reactor core. The reactors together use about 50 tons a year of low-enriched uranium containing 4.5% U-235. The United States no longer has a government-owned uranium enrichment plant that can produce the LEU for these reactors.

The last LEU for U.S. tritium production was enriched by DOE's Paducah Gaseous Diffusion Plant prior to its shutdown in June 2013. Paducah, the last operating U.S.-government-owned enrichment plant could not compete with newer, more energy-efficient commercial civilian gas-centrifuge plants that have been built by other countries, including a plant built in New Mexico by the British-Dutch-German consortium, URENCO.

DOE argues that the U.S. cannot fuel U.S. tritium-production reactors with LEU enriched in foreign-owned plants since the tritium is for nuclear weapons. The LEU from foreign-owned enrichment plants is "obligated" to be used only for peaceful purposes. It is this interpretation, which is not shared by others, including URENCO, that DOE uses to justify the current drive to build its own enrichment plant.

DOE's 2015 report to Congress, Tritium and Enriched Uranium Management Plan Through 2060 identified sources of enough LEU to fuel the Tennessee Valley Authority reactors until about 2040. If additional HEU could be released from the U.S. weapons stockpile for blend-down, however, the "unobligated" LEU supply for these reactors could be extended.

It is possible to make an independent estimate from public data of the amount of HEU the U.S. still has available for weapons and how much might be declared excess to be blended down to provide LEU fuel for the tritium-production reactors. About 1000 tons of 4.5% LEU would be required to fuel the tritium-production reactors for an additional 20 years. This could be derived by blending down 41 tons of weapon-grade HEU (93.5% U-235) uranium with natural uranium (0.72% U-235).

The United States still has more than 200 tons of HEU available for weapons, including in about 2,600 retired warheads awaiting dismantlement. Assuming, based on public information, that U.S. warheads contain an average of about 25 kilograms of HEU each, there are about 100 tons of HEU in the U.S. current nuclear stockpile of about 3,800 warheads.

This leaves more than 100 tons of HEU that is surplus to arsenal needs. If about 41 tons of HEU were to be declared excess and blended down to LEU by 2035-2055, that would be sufficient to provide for U.S. tritium production until about 2060. In that case, DOE's proposal to have a new national enrichment plant on line to produce LEU by 2038 would be premature by at least two decades. This conclusion should be checked by analysts with access to the classified information on how much HEU is in operational U.S. nuclear warheads.

Japan's Nuclear Regulation Authority on March 28 approved a 30-year plan by the Japan Atomic Energy Agency for the decommissioning and dismantlement of the Monju prototype fast-breeder reactor.

Monju has a had troubled history, like other fast-breeder reactor (for details, see "Japan's Plutonium Breeder Reactor and its Fuel Cycle" by Tatsujiro Suzuki). Construction of Monju started in 1985. It went critical in 1994 but an accident led to its shut-down in August 1995. The reactor was restarted in May 2010, but suffered another accident about four months later, in September 2010. In total, the reactor operated for about a year until in 2016 the decision was made to shut it down. Japan has spent about 1 trillion yen ($9.46 billion) on Monju so far, and the cost of the decommissioning is estimated to exceed $3.5 billion.

The reactor was finally shut down in December 2017. The Japan Atomic Energy Agency expects to begin removing fuel from Monju in July 2018.

The decommissioning and dismantlement plan anticipates demolition of the reactor building by 2047. The plan does not however explain how the radioactive sodium coolant is to be removed.

In April, the leaders of South Korea and North Korea will have their first summit meeting in over a decade. This is to be followed in May by the first ever summit meeting between the leaders of the United States and North Korea. In these meetings, a freeze on North Korean nuclear weapon and ballistic missile tests and agreement on a commitment to a verifiable path to nuclear disarmament by North Korea will be key agenda items. This will not be the first time these countries have had to think about verifying North Korean nuclear disarmament, however.

In September 2005, China, North Korea, Japan, South Korea, Russia, and the United States agreed a Joint Statement as part of the Six-Party talks that to enable "the verifiable denuclearization of the Korean Peninsula in a peaceful manner," North Korea was "committed to abandoning all nuclear weapons and existing nuclear programs and returning at an early date to the treaty on the nonproliferation of nuclear weapons (NPT) and to IAEA (International Atomic Energy Agency) safeguards."

This led in 2007 to an agreed plan for the implementation of the Joint Statement, including for North Korea to make "a complete declaration of all nuclear programs and disablement of all existing nuclear facilities."

In 2008 the US proposed a verification regime for North Korea, which was described in an undated "Verification Measures Discussion Paper" first reported in the Washington Post. The Discussion Paper was reproduced in Global Fissile Material Report 2009 and is available as a separate paper in the IPFM library:

Global Fissile Material Report 2009, Appendix 4A: U.S. Proposal for Verification of North Korea's Denuclearization.

The Discussion Paper outlined a detailed set of verification measures and claimed "These measures provide a means to address all elements of a nuclear program, to include plutonium production, uranium enrichment, weapons, weapons production and testing, and proliferation activities." In addition, there were to be "additional measures to facilitate the verification process, including additional measures to help confirm the absence of undeclared nuclear material, equipment and related activities."

The verification was to be conducted by "experts of the six parties" and was to be managed by "the Working Group on Denuclearization of the Korean Peninsula and the other members of the Six-Party talks.

U.S. Department of Energy requested an export license (XSNM3794) to ship 5.274 kg of HEU to Europe. The material will be used to manufacture targets used in production of Mo-99.

The license application seeks approval of export of "4.913 kg uranium-235 in maximum of 5.274 kg uranium, enriched to maximum of 93.35%, in the form of unalloyed broken metal." The material will be shipped to a Framatome facility in France that will manufacture the targets, which will be irradiated in BR-2 reactor in Belgium, HFR reactor in the Netherlands, LVR-15 reactor in Czech Republic, and Maria reactor in Poland. Institute for Radioelements (IRE) in Belgium, where the targets will be reprocessed, is listed as the ultimate destination of the material. Previous license of this kind, XSNM3788 for 1.45 kg of HEU, was requested in December 2017.

It is not clear why the HFR reactor in the Netherlands is listed among the reactors that will be irradiating HEU targets - in January 2018 the NRG group, the operator, reported conversion of its Mo-99 production to LEU.

UPDATE: The license XSNM3794 was issued on 23 April 2018.

by Greg Mello

During her 8 February 2018 Senate confirmation hearings as President Trump's nominee to be the new National Nuclear Security Administration (NNSA) administrator, Lisa Gordon-Hagerty said her "number one" priority would be building up the US capacity to produce plutonium cores (pits) for nuclear weapons, with a target of making at least 80 pits a year by 2030.

The United States currently has some pit production capability at Los Alamos National Laboratory (LANL), centered in LANL's main plutonium facility at Building PF-4 in TA-55. PF-4 was build 40 years ago for the purposes of research, surveillance, and prototyping, not production. Despite hundreds of millions in ongoing structural and mechanical renovation, it has been dogged with persistent safety problems and has operated only sporadically for all activities involving pits since 2013. NNSA estimates that PF-4 will come to the end of its life around 2039.

Since 1992 NNSA has invested billions of dollars in pit production at LANL, but this investment has failed to create the reliable pit production capability NNSA repeatedly said LANL already had once. According to NNSA's November 2017 "Plutonium Pit Production Analysis of Alternatives (AoA) Results and Next Steps," the agency expects to invest a further $3 billion in pit production at LANL over the coming eight years--$1 B for operations and $2 B for facility renovation and new equipment. The goal of this effort is to establish a 30 pit per year capacity in existing facilities by 2026.

Achieving an enduring post-2030 80 pit per year capacity will be even more costly. NNSA is currently considering two options. The first (and so far preferred, on bases of schedule and cost), involves repurposing all or part of the partially-completed Mixed-Oxide Fuel Fabrication Facility (MFFF) at the Savannah River Site (SRS) in South Carolina. The alternative option involves construction of new pit production facilities at LANL.

NNSA's pit production AoA document says the 80 pits per year requirement derives from "pit aging estimates and planned production schedules to meet military requirements." These requirements are also mentioned in the February 2018 Nuclear Posture Review (NPR), which stated, accurately enough, that "[t]oday, the U.S. capability to produce plutonium pits is limited to research and development pits unsuitable for stockpile use" and affirmed that "DoD requires NNSA to produce at least 80 plutonium pits per year by 2030." The report, however, contains no reference to any current or proposed warhead or warhead program which requires new pits.

The 2014 "Assessment of Nuclear Weapon Pit Production Requirements" notes that "in 2008, the Nuclear Weapons Council (NWC) ... established the requirement for 50-80 pits per year" by 2031. This 2008 justification is now a decade old and has not been re-examined in any detail in public. The only changes are the target date that has moved forward by one year from 2031 to 2030 and the production target that has increased from "50-80" pits per year to "no fewer than 80" pits per year.

The current US stockpile consists of approximately 4,018 warheads and bombs, each with a pit. This number does not include approximately 2,600 intact-but-retired weapons of recent vintage. In addition, there are in storage for possible reuse an unknown but large number of "National Security Asset" pits.

In 2008, the Department of Energy (DOE) and the Department of Defense (DoD) wrote that "depending on warhead type, the best estimate of minimum pit life is 85-100 years." The oldest pits in the stockpile were made in 1978 and therefore are 40 years old as of 2018. These oldest pits will therefore be useable, according to DOE and DoD, until at least the 2063 to 2078 period. The newest pits were made in early 1989 and will be useable until at least the 2074 to 2089 period. This means that the earliest date that replacement of today's stockpile pits would need to start is 2063, and the earliest date that replacement would need to conclude is 2074.

Discounting for the moment whatever flexibility is available from pit reuse across warhead type and other compensatory measures (including partial pit rebuild), a stockpile of the same size as today's would require 50 years to fully replace at an average production rate of 80 pits per year. Production that began in 2030 at that rate would completely replace today's stockpile by 2080.

The FY 2018 Stockpile Stewardship and Management Plan shows NNSA has no stockpile pit production scheduled at all until 2023, when just one pit is required, followed by 10, 20 and 30 pits in 2024, 2025, and 2026 respectively. Additionally, the FY 2015 National Defense Authorization Act (NDAA, Sec. 4219) required achieving a 90-day production demonstration of 80 pits per year in 2027, with up to a two-year grace period. It is not clear how NNSA expects to achieve the almost three-fold jump in pit production from 30 pits per year in 2026 to 80 pits per year in 2027. Given that NNSA's pit production Analysis of Alternatives asserts a maximum production rate in PF-4 of 30 pits per year, meeting the 2027 deadline implies bringing additional facilities into operation by that time. NNSA states that achieving this goal is unlikely but possible, though not at LANL.

Under the previous administration, the proposed Interoperable Warhead (IW-1) was the only Life Extension Program (LEP) to require new pits until 2041, when an "IW-3" was to begin production, also said to require new pits. The 2018 Nuclear Posture Review contains no reference to any interoperable warhead, except as a possible concept exploration for the future.

There is clearly a need to re-examine and publicly justify infrastructure strategies and pit production requirements. The FY18 NDAA (Sec. 3141) required NNSA to submit an analysis of alternatives regarding plutonium production capabilities and identify the preferred course of action. The report should have been submitted to the congressional defense committees in January 2018. The discussion of alternatives should focus on a number of key questions that will determine the future of U.S. pit production capability:

Is there really a need for any new pits between now and mid-century? How is the projected need in pit production capability dependent on stockpile size and composition? Where--at what site, in what facilities--should pit production take place, and with what capacity, starting when?

In practice, questions about management risk, facility age, institutional suitability, workforce training and skills, potential expansion capacity, and supporting infrastructure will loom large in NNSA's pit production decisions.

At no time since the dawn of the nuclear age has the United States been able to produce pits both safely and reliably. Can this really be done, and if so how? The United States has not been able to successfully build a plutonium handling facility since 1978. What lessons can be drawn from prior failures? Could such a facility be built and safely operated today?

Pit production decisions are intertwined with decisions about the disposition of surplus plutonium, so much so that firm decisions about the former may not be possible prior to firm decisions about the latter. Will there be a surplus plutonium disposition mission at MFFF, what will it be, and could pit production occur there as well?

Or, if the pit production mission is to stay at LANL indefinitely, how will it become institutionally compatible? Can it ever succeed? Given PF-4's advanced age, what replacement facilities will be required?

None of these questions are easy or going away soon, no matter what NNSA decides.

For more background about these issues, see US Pit Production: Background and Issues (PDF).