Tracking highly enriched uranium and plutonium, the key nuclear weapon materials

In the FY2017 budget request, submitted to Congress, the administration proposes to terminate construction of the MOX Fuel Fabrication Facility. Here is the full quote from the document (p. 456 of the Volume I, links to previous IPFM posts added):

Currently, the Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF) is the only project in [the Nonproliferation Construction] program and would enable the Department to dispose of weapon-grade plutonium by fabricating it into mixed oxide fuel and irradiating it in commercial nuclear reactors. The Consolidated and Further Continuing Appropriations Act, 2015, directed that construction on the MOX project continue and that cost studies and technology alternative studies be conducted. The National Defense Authorization Act for FY 2015 mandated an independent assessment and validation of the 2014 Plutonium Working Group (PWG) analysis. The Department requested Aerospace Corporation, a federally funded research and development center (FFRDC), [...] conduct this assessment. Aerospace Corporation completed two reports documenting its assessment of the April 2014 analysis. Additionally, in June 2015 the Secretary of Energy assembled a Red Team to assess options for the disposition of surplus weapon-grade plutonium. These analyses confirm that the MOX fuel approach will be significantly more expensive than anticipated and will require approximately $800 million to $1 billion annually for decades. As a result, the FY 2017 budget proposes that the MOX project be terminated. The Department will complete pre-conceptual design for the dilute and dispose (D&D) option to establish critical decision-0 (CD-0), Approve Mission Need, and begin conceptual design in late FY 2017.

The administration expressed its intent to terminate the MFFF construction in 2014, when it was put on "cold standby". However, later that year the Nuclear Regulatory Commission extended the construction license until 2025 and Congress continued to fund the construction activities. The decision to terminate the MFFF construction is likely to face continuing opposition from supporters of the project.

A committee of the National Academies of Sciences, Engineering, and Medicine released a report Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. The congressionally mandated report urges the U.S. government to take a number of steps to reduce the use of HEU in research reactors.

The report calls for development of a long-term national strategy that would ensure that the future need for neutrons in civilian applications can be met with sources that do not use HEU. It recommends that the United States continue to develop very high-density LEU fuels that could be used in U.S. high-performance research reactors and closely monitor LEU fuel development programs in other countries to evaluate their potential use in U.S. reactors.

The report recommends pursuing an interim solution to reducing the use of HEU. It would involve the following steps:

  1. Conversion of U.S. high-performance research reactors to dispersion silicide fuel enriched to the lowest practical level;
  2. Downblending of 20 MT of HEU designated for civilian research reactors to the lowest practical enrichment level;
  3. Continuing the effort toward the long-term goal of eliminating HEU usage in civilian applications.

The NAS report also supports expanding international cooperation on HEU minimization and makes some specific recommendations regarding the management of the HEU minimization program in the United States.

Frank von Hippel (Princeton University) and Edwin Lyman (Union of Concerned Scientists)

In November 2015, High Bridge Associates released a report questioning the feasibility of putting more plutonium into the deep-underground Waste Isolation Pilot Plant (WIPP) in New Mexico, and raised the specter that the plutonium might undergo a chain reaction such as happens in a nuclear reactor or nuclear explosion. The report thereby questioned the feasibility of the plan being considered by the U.S. Department of Energy (DOE) to dispose in WIPP dozens of tons of plutonium that it no longer needs for nuclear weapons. The scenario raised in High Bridge report had been studied by Sandia National Laboratories in 2001, however, and found to be impossible.

The High Bridge report was prepared under contract with MOX Services, the prime contractor for the construction at the DOE's Savannah River Site of the hugely over cost, greatly delayed and very controversial MOX Fuel Fabrication Facility, which was to turn at least 34 tons of excess U.S. weapons plutonium into reactor fuel for use in nuclear power reactors.

Three different DOE-commissioned studies have concluded that disposing of the 34 tons of excess US weapon plutonium in WIPP would be a much less costly disposal approach than completing the MOX project (Report of the Plutonium Disposition Working Group, Plutonium Disposition Study Options, and Final Report of the Plutonium Disposition Red Team). MOX Services has been fighting this option and the new High Bridge report is part of its struggle to keep the MOX plant option alive.

In December, the U.S. Department of Energy (DOE) announced that dilution and disposal in WIPP is its preferred option for disposal of 6 metric tons of plutonium currently in storage at its Savannah River Site. The proposed plutonium waste packages (known as Criticality Control Overpacks, or CCOs) would each contain up to 380 grams of plutonium-239 (Pu-239) equivalent in a mixture that is less than 10 percent plutonium by weight inside a stainless steel pipe emplaced inside a drum with a volume of 208 liters (55 gallons).

The High Bridge report argues, however, that

"A 55-gallon drum is not designed to survive for thousands of years in this environment and the weight of the salt will eventually crush the 55-gallon drums potentially moving the plutonium in the CCOs [Criticality Control Overpacks] into a critical geometry. Since each shipment of CCOs containing surplus weapons plutonium would contain approximately five critical masses, this process needs to be analyzed and evaluated as part of a Supplemental FEIS. It is likely that this issue applies to any quantity of surplus weapons plutonium shipped to WIPP."

In fact, Sandia National Laboratories' Nuclear Waste Management Program published an analysis of exactly this scenario in 2001. It found that, if water invaded the repository, a mixture of Pu-239 and rust in water could not go critical until the average concentration of Pu-239 reached 20 kilograms per cubic meter (kg/m3). It estimated that crushing could reduce the volumes of the drums by a factor of up to six. On that basis, the average concentration of plutonium would be 11 kg/m3, still about a factor of two below the minimum average concentration required for criticality. If a greater margin were desired, some relatively non-crushable and insoluble material (e.g. pebbles) could be added to the containers to reduce the factor by which they could be compressed.

Finally, it is important to put the possibility of a criticality in WIPP into perspective. Even if it occurred, it would almost certainly be confined in the repository. The behavior of the famous natural reactors that went critical in uranium deposits in Gabon 1.8 billion years ago provides a possible model. The criticalities occurred because natural uranium in that era contained four times as much chain-reacting U-235 as it does today. The reactors released their energy at low rates, cycling on and then off again, as the fission heat increased the temperature - and perhaps even drove off the neutron-slowing water that made the chain reactions possible. This self-regulating effect would be increased if the plutonium were mixed with depleted uranium (U-238) due to increased neutron absorption in U-238 resonances as it heats up. Mixing with U-238 also would prevent the plutonium from decaying into highly enriched uranium (Pu-239 decays into U-235 with a 24,000-year half-life).

Tom Clements, Savannah River Site Watch

The U.S. Department of Energy (DOE) has made an initial decision to prepare 6 metric tons of surplus plutonium to be disposed of as nuclear waste. The decision is of note as it comes at a time when the fate of plutonium fuel (MOX) project at the Savannah River Site is uncertain.

The plutonium, now stored at the DOE's Savannah River Site in South Carolina, is to be prepared "for eventual disposal at the Waste Isolation Pilot Plant (WIPP) in Carlsbad, New Mexico, a geologic repository for disposal of Transuranic (TRU) waste generated by atomic energy defense activities."

The decision, by DOE's National Nuclear Security Administration (NNSA), comes after a lengthy environmental review process that began in July 2010 to analyze "the potential environmental impacts for the disposition of 13.1 metric tons (14.4 tons) of surplus plutonium for which a disposition path is not assigned, including 7.1 metric tons (7.8 tons) of plutonium from pits that were declared excess to national defense needs and 6 metric tons (6.6 tons) of surplus non-pit plutonium."

On December 24, 2015, NNSA issued a notice in the Federal Register entitled "Preferred Alternative for Certain Quantities of Plutonium Evaluated in the Final Surplus Plutonium Disposition Supplemental Environmental Impact Statement" in which the decision was made to dispose of 6 MT of plutonium in WIPP. But it won't be final until DOE/NNSA issues a formal Record of Decision (ROD) no sooner than 30 days from the date of publication of the notice in the Federal Register.

In April 2015, DOE issued the Final Surplus Plutonium Disposition Supplemental Environmental Impact Statement (Final SPD Supplemental EIS, DOE/EIS-0283-S2). The document analyzed various disposition alternatives for the surplus plutonium, including via plutonium fuel (MOX) irradiation in the Sequoyah and Browns Ferry reactors owned by the Tennessee Valley Authority, via immobilization in high-level nuclear waste at SRS and via disposal in WIPP. No "Preferred Alternative" for plutonium disposition was chosen in that document.

In the Federal Register notice of December 24, it was affirmed that "DOE/NNSA has no Preferred Alternative for the disposition of the remaining 7.1 MT of surplus plutonium from pits, nor does it have a Preferred Alternative among the pathways analyzed for providing the capability to disassemble surplus pits and convert the plutonium from pits to a form suitable for disposition." Thus, DOE remains undecided on MOX use in reactors owned by TVA reactors (the only nuclear utility that has expressed interest in MOX use).

While DOE has made the announcement on sending 6 MT of plutonium to WIPP, many hurdles remain to carry out this decision once the ROD is issued. No funding has been appropriated by Congress for downblending the plutonium at SRS for disposal. SRS currently lacks adequate infrastructure to carry out the mission and would need more gloveboxes, likely to be placed in the K Area, for packaging the material mixed with a secret inert material (called "stardust") from which it DOE believes it would be difficult to recover the plutonium so that the safeguards can be terminated.

The WIPP facility remains closed after accidents in February 2014 and the schedule for its "recovery" and reopening is unclear. Additionally, the volume of TRU waste going into WIPP was established under the Land Withdrawal Act and the ability of the facility to handle a large volume of packaged plutonium needs further analysis. At this time, it is unknown what level of political opposition there may be in New Mexico to taking plutonium to WIPP, which already has received 4.5 MT of plutonium as waste. The first shipment of plutonium from SRS to WIPP took place in 2012.

Funding and construction problems continue to plague the mismanaged MOX project but its fate will not begin to be known until the DOE releases its Fiscal Year 2017 budget to Congress on February 1, 2016. If MOX faces termination, the 6 MT of plutonium now designated to go to WIPP could be dramatically increased to include a significant portion of the 49 MT of separated plutonium that so far has been declared surplus to U.S. defense needs beyond the 4.5 tons already in WIPP.

On 22 December 2015, the IAEA announced successful removal of 1.83 kg of HEU that from the Breeder-1 neutron activation facility in the Andronikashvili Institute of Physics in Tbilisi, Georgia. The material was transferred to a "secure storage facility" in Russia, most likely the NPO Luch in Podolsk, Russia.

The Breeder-1 facility was built around a PS-1 subcritical assembly that used 36% HEU in uranium oxide fuel. The core contained 660 g of U-235. PS-1 was designed and built at the VNIIRT in Moscow (currently NIITFA) in the early 1970s. The assembly (or its copy) was then transferred to Tbilisi.

According to the IAEA, Government of Georgia requested assistance in removing the material in June 2015.

It is notable that the PS-1 material was not included in the previous HEU removal operation, Auburn Endeavor, which took place in 1998. At the time, the United States and the United Kingdom removed from Georgia about 4.3 kg of fresh and 0.8 kg of spent HEU fuel of the IRT-M reactor. Since then, the GTRI program listed Georgia as a country that is free of HEU.

The International Panel on Fissile Materials research report, Alternatives to MOX: Direct-disposal Options for Stockpiles of Separated Plutonium, by Frank von Hippel and Gordon MacKerron is now available in Chinese. The report was originally release in April 2015. The link to the pdf file is below:

弗兰克·凡·希佩尔(Frank von Hippel)和戈登·麦克寇朗(Gordon MacKerron),将钚制成MOX燃料进行处置的替代方案,研究报告之No.13,国际易裂变材料专家组(IPFM),2015年4月。

The report reviews programs in France, Japan, the United Kingdom and the United States to dispose of large stocks of separated plutonium in nuclear power reactor mixed-oxide (MOX) fuel. Most of these efforts have suffered long delays and large cost increases and all have failed to reduce plutonium stockpiles. This has led some of these countries to consider alternatives.

A less costly and more effective approach may be to treat plutonium as a waste to be processed into a stable form and deeply buried. These alternative approaches include disposal with radioactive waste or spent fuel or disposal down a 3-mile (5-kilometer) deep borehole.

The report recommends that more than one direct-disposal approach be pursued. It also recommends that the countries that share the problem of plutonium disposal collaborate on exploring direct-disposal options. Finally, it recommends that the quantities of plutonium disposed by the weapon states be verified by the IAEA.

The overview chapter of the International Panel on Fissile Materials's research report Plutonium Separation in Nuclear Power Programs: Status, Problems, and Prospects of Civilian Reprocessing Around the World, released in June 2015, is now available in Chinese. The link to the pdf file of the report is below:


The report looks at the history, current status and prospects of programs aimed at separating plutonium for civilian use from spent fuel produced by nuclear power reactors. Today only China, France, India, Japan, Russia and the United Kingdom have active civilian reprocessing programs, and all of these programs are detailed in the report. The report also looks at the rise and fall of reprocessing in Germany and the agitation in South Korea for starting a program.

This global overview of reprocessing shows the world is closer to the end of separating plutonium and the associated security, economic and environmental dangers. The country studies in the report offer insight into the institutional forces that have sustained national commitments to separating plutonium in the face of economic incentives to desist from this practice. The report also outlines various processes that can overcome such institutional resistance in time and lead to the end of spent fuel reprocessing and plutonium separation.

Contributors to the report are Anatoli Diakov, Klaus Janberg, Jungmin Kang, Gordon MacKerron, M. V. Ramana, Mycle Schneider, Masafumi Takubo, Gordon Thomson, Frank von Hippel, Hui Zhang, and Yun Zhou. The report was edited by Frank von Hippel and M. V. Ramana. Michael Schoeppner provided editorial support.

The International Panel on Fissile Materials has released Global Fissile Material Report 2015: Nuclear Weapon and Fissile Material Stockpiles and Production (PDF). This is the eighth Global Fissile Material Report.

The report provides updated estimates for global and national stockpiles of HEU and plutonium, the key ingredients in nuclear weapons and recent developments in military and civilian fissile material production capabilities in nuclear weapon states and in the non-weapon states.

In 2015, the global stockpile of nuclear weapons was estimated at over 15,800 weapons, with the United States and Russia together holding about 14,700 of these weapons and the other seven nuclear weapon states holding a combined total of about 1100 weapons.

The global stockpile of HEU at the end of 2014 was about 1370 ± 125 tons, enough for more than 76,000 simple, first generation fission implosion weapons. About 99 percent of this material is held by the nuclear weapon states, mostly by Russia and the United States. The large uncertainty in the HEU estimate is due to a lack of official information about Russia's historical production of HEU. The uncertainty in the size of the Russian HEU stockpile is larger than the total HEU stocks held by all other states except for the United States.

The United States, United Kingdom, Russia, France and China all stopped producing HEU for weapons, in some cases decades ago. Today, only India, Pakistan and possibly North Korea are believed to be producing HEU for weapons purposes. Russia has restarted HEU production to meet the need for reactor fuel.

In 2014, for the first time in about two decades, the global HEU stockpile stopped shrinking and remained nearly constant after Russia ended its down blending of excess HEU to low-enriched uranium for sale to the United States. The United States has about 40 tons of excess HEU remaining to be blended down, which is scheduled to be completed by 2030. Neither country has declared any additional HEU excess.

The global stockpile of separated plutonium as of the end of 2014 was about 505 ± 10 tons. Less than half of this stockpile was produced for weapons. The majority of the global plutonium stockpile is the result of civilian programs in nuclear weapon states, some of it for foreign customers. As a result, about 98 percent of all separated plutonium is stored in the nuclear weapon states.

The stockpile of separated plutonium for weapons continues to increase because of continued production in Israel, India, and Pakistan. As of late 2015, the United States and Russia have still not started verifiably disposing of the 34 tons of plutonium that each declared as excess to weapon purposes.

There are about 53 tons of plutonium owned by the non-weapon states, most of which is in storage in France and the United Kingdom, and mostly belongs to Japan.

The report features a new section "Nuclear Weapons, Fissile Materials and Transparency" updating the material presented in Global Fissile Material Report 2013: Increasing Transparency of Nuclear Warhead and Fissile Material Stocks as a Step toward Disarmament, released in October 2013.

This section includes a transparency matrix assessing progress by the nuclear weapon states on meeting their obligations under the terms of the 2010 "Action Plan on Nuclear Disarmament," to cooperate on steps to increase transparency about arsenals and fissile material stockpiles and to develop verification capabilities related to nuclear disarmament and in particular to report information that can further openness and verification.

Michael Schoeppner of Princeton's Program on Science and Global Security provided editorial assistance in preparing Global Fissile Material Report 2015.

Shaun Burnie (with Mycle Schneider)

Thirty-one years after construction start, the BN-800 Fast Breeder Reactor (FBR) at Zarechnyy, in the Sverdlovsk region of Russia, was connected to the grid on December 10, 2015 at 21:21 (19:21 MSK). In the beginning the reactor will be operating at about 35 percent of its power. According to the IAEA, the BN-800 has a nominal net capacity of 789 MWe. The reactor first reached criticality in June 2014.

The extremely long construction time is no exception. Russia has connected only four reactors to its power grid over the past ten years (including the BN-800) and the average construction time was just under 30 years.

The BN-800 is eventually to be fueled with surplus weapons grade plutonium manufactured into plutonium-uranium Mixed Oxide (MOX) fuel, produced at the MOX fabrication plant in Zheleznogorsk, which produced first fuel in September 2015. However, BN-800's initial core is a combination of MOX fuel with pellets supplied by the Mayak Plant, Chelyabinsk region and vibro-packed MOX from the Research Institute of Atomic Reactors (NIIAR, Dimitrovgrad, Ulyanovsk region). Of the total of 576 fuel assemblies in the initial core, 102 are fuel assemblies with high-enriched uranium.

A full MOX core with reactor-grade plutonium would contain 2,710 kg, while the use of weapons-grade plutonium would limit the quantity to 2,215 kg.

The Russian FBR program has limited experience with plutonium based MOX fuel. Due to a combination of cost and safety issues, most of the fuel used in the BN-350 and BN-600 reactors has been based on uranium with enrichment from 17% to 26%. Some experience with plutonium fuel was acquired in the experimental BOR-60 reactor and in a few experimental fuel assemblies in BN-350 and BN-600.

Under the United States-Russia Plutonium Management and Disposition Agreement (PMDA), signed in 2000, each nation agreed to dispose of at least 34 tons of surplus weapons-grade plutonium. The original plan by Russia to fabricate MOX fuel and use it in light water reactors was amended with an additional protocol to the PMDA, signed in 2010, whereby the 34 tons of plutonium would be "burned" in fast reactors. The change reflected the long-standing commitment in Russia to a nuclear power program based on "closed nuclear fuel cycle", including reprocessing and FBRs. However, earlier Russian plans in the 1980's to construct five BN-800s in the Ural region failed to materialize. Its current plans to scale up FBR deployment to 14 GWe by 2030 and 34 GWe of capacity by 2050 no not seem realistic. Plans for the next stage in fast reactor development, the BN-1200, scheduled to be operational by 2025, have been postponed due to doubts over its economic viability. As part of its "Breakthrough" program, Rosatom is also working on another FBR design, Brest-300. Preparation for the construction of the pilot unit, Brest-OD-300, are underway in Seversk (formerly Tomsk-7).

As a fast neutron reactor, the BN-800 will be capable of breeding additional plutonium, which is one reason Article VI of the PMDA Agreement imposes a ban on spent fuel and breeder blanket reprocessing during the disposition process until disposition of plutonium covered by the PMDA is complete. However, before that time, Russia can reprocess up to 30 percent of the fuel discharged by the BN-800, provided that it was made with plutonium other than disposition plutonium.

On November 30, 2015 President Cristina Fernandez of Argentina took part in a ceremony that appears to beginning of operations at the Pilcaniyeu enrichment plant. The start of operations, in fact, was announced earlier, in February 2015, but it is possible that the plant was operating in test mode since then. The work on restarting the facility began in 2010.

The initial capacity of the plant, built in the late 1970s and shut down in 1996, was 20,000 SWU/year. The current project calls for increasing the capacity to as much as 3 million SWU/year.