Surplus Plutonium Disposition: NNSA's Long-Term Plutonium Oxide Production Plans Are Uncertain

The United States has 57.2 MT of weapons-usable plutonium that it has declared surplus and that still requires disposition. This plutonium exists in various metal and non-metal forms, including pits—the central core of a nuclear weapon. To prevent insidious use of this plutonium, DOE plans to disassemble pits into metal; convert the plutonium metal to plutonium oxide, a powder-like substance; dilute it with inert material; and dispose of it at WIPP. In May 2018, NNSA issued a plan conceptualizing the dilution and disposal of 34 MT of surplus plutonium at an estimated cost of $19 billion over the next 3 decades. Under this conceptual plan, pit disassembly and production of plutonium oxide would take place at one facility and dilution would be performed in another, with both operations expanding over the next decade.

GAO was asked to review DOE's plans for plutonium oxide production to dispose of surplus plutonium. This report (1) examines the amount of surplus plutonium in DOE's inventory that could be converted to plutonium oxide for dilution and disposal and (2) examines DOE's capacity to produce plutonium oxide. GAO reviewed the inventory of surplus plutonium, plutonium oxide production requirements and production capacity, and DOE planning documents, and interviewed DOE officials.

Of the Department of Energy‘s (DOE) inventory of surplus plutonium, about 43.8 metric tons (MT), or 77 percent, is plutonium metal that could be converted to plutonium oxide for dilution and disposal. Of this amount, the National Nuclear Security Administration (NNSA) manages 33.3 MT in the form of pits, DOE's Office of Environmental Management (EM) manages 6.5 MT, and DOE's Office of Nuclear Energy manages 4 MT in the form of reactor fuel. EM manages another 11 percent, or 6.4 MT, of DOE's surplus plutonium that is already in oxide form. Most of this is suitable for dilution and disposal at the Waste Isolation Pilot Plant (WIPP), a repository in New Mexico. An additional 12 percent, or 7 MT, of DOE's surplus plutonium is contained in spent nuclear fuel that is planned for disposal in a geologic repository. See figure.

NNSA's 2018 conceptual plan calls for converting 26.2 MT of this surplus plutonium into oxide by 2045. In September 2019, NNSA approved the production of about 1.2 MT of plutonium oxide through 2025 at its Los Alamos National Laboratory (LANL) located in New Mexico. However, plans for converting additional surplus plutonium into plutonium oxide are uncertain because of two issues. These issues include NNSA's still-developing plans for new pit production, which will also take place at LANL, and issues surrounding the agency's ability to ship newly produced plutonium oxide for dilution to DOE's Savannah River Site (SRS) in South Carolina. According to agency officials, NNSA and DOE are taking several actions that, if successfully implemented, are designed to allow NNSA to meet its long-term plutonium oxide production goals. These actions include continuing to review plutonium oxide and pit production plans, increasing plutonium storage at LANL, reducing the amount of SRS's surplus plutonium, and accelerating the shipment of diluted plutonium from SRS to WIPP.

Plutonium, a radioactive element that is produced by irradiating uranium  in nuclear reactors, is an essential component of nuclear weapons and  U.S. national defense strategy. Plutonium is used to manufacture pits,  the central core of a nuclear weapon. During the Cold War, the United  States manufactured thousands of pits to maintain its stockpile of nuclear  weapons. However, since the Cold War ended in the early 1990s the  stockpile has been reduced, leaving thousands of pits from dismantled  nuclear weapons sitting in temporary storage. In addition to plutonium  from pits, several metric tons (MT) of non-pit plutonium—some of which  were used in the pit manufacturing process—used (spent) nuclear fuel,  and other nuclear fuels containing plutonium are also in temporary  storage.

Plutonium poses a proliferation risk and a risk to human health and the  environment if not managed safely. The threat of state or non-state  actors, such as terrorists, developing nuclear or radiological weapons by  obtaining some of this plutonium poses one of the greatest challenges to  U.S. and international security, according to the National Nuclear Security  Administration (NNSA), a separately organized agency within the  Department of Energy (DOE).

In part to address this proliferation risk, DOE established the Surplus  Plutonium Disposition Program in 1997 to dispose of surplus, weapons- usable plutonium at the end of the Cold War. According to NNSA, the  disposition of surplus plutonium is central to the nuclear non-proliferation  goals of the United States and is primarily managed by its Office of  Material Management and Minimization. As of 2007, the United States  had declared a total of 61.5 MT of plutonium as surplus to defense  needs. DOE has disposed of 3.2 MT of surplus plutonium at the Waste  Isolation Pilot Plant (WIPP), an underground repository for transuranic  waste located near Carlsbad, New Mexico, and is in the process of  disposing of an additional 1.1 MT of surplus plutonium. As a result, as of  May 2019 DOE had 57.2 MT of surplus plutonium in its inventory still  requiring disposition.

In the 1990s, DOE considered several strategies to dispose of the surplus  plutonium and, according to DOE documents, in 1997 decided on two  strategies to immobilize and irradiate the surplus plutonium before final  disposal in a geologic repository for high-level waste, including spent  nuclear fuel. Immobilization encapsulates the plutonium in glass or  ceramic materials prior to disposal. Irradiation requires that the plutonium  be converted to plutonium oxide, a powder-like substance, and then  blended with uranium oxide to make mixed oxide (MOX) fuel. This MOX  fuel, which DOE planned to fabricate at the Mixed Oxide Fuel Fabrication  Facility (MFFF) at the Savannah River Site (SRS) in South Carolina,  would then be used in U.S. commercial nuclear reactors to produce  electricity. The plutonium in the MOX fuel would be incorporated into  spent nuclear fuel, a form that would prevent it from being easily used in  nuclear weapons, and would eventually be disposed of in a high-level  waste repository.

In 1999, DOE began planning for the disposition of up to 50 MT of surplus  plutonium using the immobilization and MOX fuel strategies but changed  that amount to 34 MT as part of an agreement signed with Russia. Under  the Plutonium Management and Disposition Agreement (PMDA), signed  in 2000 and amended in 2006 and 2010, the United States and Russia  pledged to dispose of at least 34 MT of surplus weapons-grade plutonium  no longer needed for defense purposes, primarily by irradiating certain  forms of surplus plutonium as MOX fuel in commercial nuclear reactors.

As we have previously reported, DOE’s cost and schedule estimates for  the MFFF grew significantly. In 1997, DOE originally estimated that  constructing the MFFF would cost about $1.4 billion and be completed in  2004; however, in 2012, NNSA estimated construction costs of $7.4  billion and completion by 2019. In 2016, DOE estimated that construction  of the MFFF would cost about $17.2 billion and be completed by 2048. In  September 2017, we found that DOE’s 2016 cost estimate for the MFFF  could be considered reliable as it substantially met all four characteristics  of a high-quality cost estimate: comprehensive, well-documented,  accurate, and credible. We also reported that NNSA’s life-cycle costs for  the Surplus Plutonium Disposition Program were $56 billion, an increase  of nearly $32 billion over its 2013 life-cycle costs.

Because of the high cost of the MFFF, NNSA began to assess alternative  strategies for plutonium disposition. In April 2014, NNSA identified an  alternative strategy that it believed could significantly reduce the life-cycle  cost of surplus plutonium disposition. Under this strategy, referred to as  dilute and dispose, NNSA would convert surplus metal plutonium to  plutonium oxide, which could then be diluted by mixing it with inert  material to inhibit plutonium recovery and prevent its future use in  weapons or diversion for any insidious use. The plutonium oxide could  then be packaged for permanent disposal at WIPP. In a letter to the  Senate Armed Services Committee in August 2016, the Secretary of  State wrote that the United States remained committed to the safe  disposition of surplus U.S. plutonium for broader nonproliferation, arms  control, and foreign policy interests and that the dilute and dispose  strategy was the only way to meet disposition targets in a fiscally  sustainable way. In May 2018, NNSA issued a conceptual plan for the  dilution and disposal of 34 MT of surplus plutonium.

The National Defense Authorization Act for Fiscal Year 2018 allowed  DOE to terminate construction of the MFFF if, among other things, DOE  identified an alternative that would cost less than approximately half of the  MOX fuel strategy. In its 2018 conceptual plan, NNSA estimated that  the dilute and dispose strategy life-cycle cost would be $19.6 billion, less  than half the estimated $49.4 billion total life-cycle cost of the MOX fuel  strategy. In May 2018, DOE notified Congress of its decision to cancel  MFFF construction, and in October 2018, DOE issued a notice of  termination of the contract for the MFFF, leaving the dilute and dispose  strategy as its preferred potential disposition strategy.

The Senate committee report accompanying S. 1519, a bill for the  National Defense Authorization Act for Fiscal Year 2018, included a  provision that we review DOE’s current capacity and plans to meet the  plutonium oxide production needs of the plutonium disposition program.  This report (1) examines the amount of surplus plutonium in DOE’s  inventory that could be converted to plutonium oxide for dilution and  disposal and (2) examines DOE’s capacity to produce plutonium oxide.

To determine the amount of surplus plutonium in DOE’s inventory that  could be converted to plutonium oxide for dilution and disposal, we  reviewed relevant DOE documents and interviewed officials from DOE,  including NNSA and the Office of Environmental Management (EM), on  the amounts and forms of surplus plutonium DOE manages, including  disposition plans. We also reviewed DOE documents and interviewed  officials on the portions of plutonium in DOE’s inventory that would  require conversion to an oxide prior to dilution. We visited the Los Alamos  National Laboratory (LANL) in New Mexico, where plutonium is converted  to an oxide, to review documentation and interview officials in the Surplus  Plutonium Disposition Program for information on past management of  surplus plutonium.

To examine DOE’s capacity to produce plutonium oxide, we reviewed  relevant DOE documents and interviewed officials from DOE, including  NNSA and EM, on their facilities and plans to convert plutonium metal to  an oxide, including time frames, conversion rates, and plans for  expanding their conversion capacity. During our site visit to LANL, we  toured Plutonium Facility-4 (PF-4), where NNSA’s Advanced Recovery  and Integrated Extraction System (ARIES) operations disassemble  plutonium pits and convert surplus plutonium to an oxide. Also, during our  visit to LANL, we reviewed documentation, spoke with officials on plans to  expand plutonium oxide conversion capacity in PF-4, and observed the  space that NNSA officials said was available for planned expansion.  Appendix I contains additional detail on our scope and methodology.

We conducted this performance audit from October 2017 to October 2019  in accordance with generally accepted government auditing standards.  Those standards require that we plan and perform the audit to obtain  sufficient, appropriate evidence to provide a reasonable basis for our  findings and conclusions based on our audit objectives. We believe that  the evidence obtained provides a reasonable basis for our findings and  conclusions based on our audit objectives.

Several DOE Offices Manage Multiple Forms of Surplus Plutonium

Three DOE offices manage 57.2 MT of plutonium declared surplus to  defense needs. These offices—NNSA, EM, and DOE’s Office of Nuclear  Energy (NE)—and their sites manage a variety of surplus plutonium in  the form of pits, metal, oxide, spent nuclear fuel, and other reactor fuels,  and they follow specific procedures to manage the plutonium safely and  securely. NNSA manages over half of this surplus plutonium. According  to NNSA, all three offices share the responsibility for final disposition of  surplus plutonium. Figure 1 shows the amounts of surplus plutonium  managed by the offices.

Figure 2 shows the various forms of this surplus plutonium, including pits,  non-pit metal, non-pit oxide, and spent nuclear fuel or other reactor fuels  in the inventory, by DOE office.

DOE’s Surplus Plutonium Disposition Strategies Have Changed over Time

Since 1997, DOE’s surplus plutonium disposition strategies have  changed in terms of the method of disposal and the location for disposal,  according to DOE documents and officials. These disposition strategies  have included immobilization, irradiation as MOX fuel, and dilution. In  1997, NNSA planned to immobilize surplus plutonium by encapsulating it  in glass or ceramic materials but terminated its plans in 2002 due to  budget constraints. In the mid-2000s, EM briefly considered vitrification,  which is a form of immobilization using glass, but never developed a plan  to implement it. NNSA planned to irradiate surplus plutonium as part of  the MOX fuel strategy but terminated its plans in 2018 because of high  costs. NNSA’s plans for irradiation of MOX fuel would also have required  disposal of the spent nuclear fuel in a high-level waste repository. EM  began implementing a dilute and dispose strategy for a separate portion  of surplus plutonium in 2012, but suspended its efforts until it resumed  them in 2016. NNSA’s 2018 conceptual plan for the dilute and dispose  strategy would replace the MOX fuel strategy with final disposal of the  diluted plutonium at WIPP. Figure 3 shows a timeline of the changes in  DOE’s strategies since 1997, as well as some key events that have  affected the strategies. See appendix II for a timeline of DOE’s disposition  strategies and appendix III for a timeline of key events concerning DOE’s  Surplus Plutonium Disposition Program.

Even if NNSA and EM had successfully implemented strategies for  immobilization, vitrification, or irradiation of MOX fuel, DOE would have  had no place to dispose of the surplus plutonium that was prepared for  disposal because it planned to dispose of this material in a high-level  waste repository, and no high-level waste repository has yet been  constructed. WIPP would not have been able to take surplus plutonium  from these disposition strategies because federal law authorizing disposal  of radioactive waste at WIPP specifically bans the disposal of high-level  waste and spent nuclear fuel, and the final forms of the surplus plutonium  from these disposition strategies would have included both. DOE’s  plans for a high-level waste repository have also changed over time. No  progress toward licensing and building a high-level waste repository has  been made since DOE terminated its licensing efforts in 2010. A high- level waste repository is likely still decades away from becoming  operational. Appendix IV contains more information on the progress DOE  has made toward licensing and building a high-level waste repository.

NNSA’s Dilute and Dispose Strategy Requires That Pits Be Dismantled and Plutonium Metal Be Converted to an Oxide

NNSA’s current dilute and dispose strategy requires that surplus pits, as  well as other surplus plutonium in metal form, be converted to plutonium  oxide. NNSA’s now-terminated strategy to use surplus plutonium to make  MOX fuel also required that surplus plutonium be converted to plutonium  oxide.

In the early 2000s, NNSA had planned to build a facility—the Pit  Disassembly and Conversion Facility at SRS—that was to be dedicated  to disassembling pits and converting them to plutonium oxide to meet the  high plutonium oxide production requirements for manufacturing MOX  fuel. Because of its high costs, however, NNSA canceled the Pit  Disassembly and Conversion Facility in January 2012 after having spent  $730.1 million on its design, as we reported.

In August 2012, DOE provided a report to Congress that described a mix  of plutonium oxide production capabilities to replace the canceled Pit  Disassembly and Conversion Facility. According to the 2012 report, DOE  planned to convert at least 2 MT of surplus plutonium pits to plutonium  oxide by 2018 in PF-4 at LANL and an additional 3.7 MT of plutonium  oxide at SRS by 2017. According to its 2012 report, NNSA planned for  this plutonium oxide to be a reserve of advance feedstock for the MFFF.  NNSA anticipated it would begin operations in 2019. According to NNSA,  SRS turned out not to be cost-effective at producing plutonium oxide.  Specifically, SRS produced 35 kilograms (0.035 MT) of plutonium oxide at  SRS’s H Canyon facility over a 2.5-year period ending in 2018. NNSA  discontinued plutonium oxide production at H Canyon and focused its  plans on expanding ARIES operations at PF-4. According to NNSA,  ARIES operations at PF-4 currently host the nation’s only cost-effective  plutonium oxide production capability.

In 1998, DOE established ARIES at PF-4 at LANL in New Mexico as a  technology demonstration project to dismantle pits and convert plutonium  metal into an oxide, incorporating automation to reduce liquid waste and  workers’ exposure to radiation. ARIES’s technology for converting  plutonium to plutonium oxide was designed to generate very little  chemical waste and to permit the application of automation, which  significantly reduces the risk of workers’ exposure to radiation. Pits have  historically been disassembled by a cutting machine. Before ARIES’s  technology, recovery of plutonium from cut pits was by an aqueous  process—that is, by using liquid chemical processing—which generated  significant volumes of both liquid and solid waste.

In 2008, NNSA shifted the ARIES mission from a technology  demonstration project to a small plutonium oxide production capability.  According to NNSA officials, ARIES has produced approximately 1 MT of  plutonium oxide from pits since it was established in 1998, with peak  production of 242 kilograms (0.242 MT) in 2011 during a partial year of  operations. NNSA officials explained that ARIES did not produce larger  amounts of plutonium oxide because the agency was still evaluating  alternatives for expanding plutonium oxide, but they estimated that ARIES  could produce 300 kilograms to 400 kilograms in a full year of operations.  In addition, LANL shut down the PF-4 facility, including ARIES, from June  2013 through September 2016 to correct safety and operational issues.  During this time, plutonium oxide production using ARIES in PF-4 was  suspended.

Plutonium oxide is the preferred form for long-term storage of plutonium  because it is relatively stable compared to other forms. Plutonium oxide is  also the form of plutonium that is most suited for dilution. ARIES consists  of glove boxes, furnaces, and other equipment to dismantle a pit and extract the plutonium;  convert the plutonium into an oxide form; mill and blend the plutonium oxide;  conduct physical and chemical analyses of the plutonium oxide; and package and store the plutonium oxide for eventual disposition.

NNSA’s 2018 conceptual plan to dilute and dispose of surplus plutonium  calls for plutonium metal to be converted to plutonium oxide using ARIES  at PF-4 and then for the plutonium oxide to be diluted at SRS for eventual  disposal at WIPP. Figure 4 shows the dilute and dispose strategy as  described in NNSA’s 2018 conceptual plan.

DOE Could Convert 43.8 MT, or About 77 Percent, of Surplus Plutonium in Its Inventory to Plutonium Oxide for Dilution and Disposal

DOE could convert 43.8 MT, or about 77 percent, of surplus plutonium in  its inventory of 57.2 MT to plutonium oxide for dilution and disposal  because this plutonium is in a metal form suitable to oxidation, based on  our review of DOE’s inventory of surplus plutonium. Most of this surplus  plutonium metal—33.3 MT—is in the form of pits and is managed by  NNSA. EM manages 6.5 MT of surplus plutonium metal and NE manages  the remaining 4 MT of surplus plutonium metal reactor fuel at Idaho  National Laboratory. Separately, EM also manages 6.4 MT of surplus  plutonium that is already in oxide form. Figure 5 shows the forms of  surplus plutonium in DOE’s inventory of 57.2 MT of surplus plutonium  requiring disposition.

As noted above, EM manages 6.4 MT, or 11 percent, of surplus  plutonium that already exists as plutonium oxide. According to NNSA  officials, SRS is currently diluting this oxide at a modest rate of about 20  kilograms (0.02 MT) annually. According to NNSA documents, the agency  plans to add additional throughput capacity within a decade.

The remaining 7 MT of surplus plutonium, or about 12 percent of DOE’s  surplus plutonium inventory, is contained in spent nuclear fuel and is not  suitable for conversion to plutonium oxide. This material would require  additional chemical processing steps to make it suitable for conversion to  plutonium oxide. DOE officials said that they planned to dispose of the 7  MT of spent nuclear fuel in a deep geologic repository, which would avoid  necessitating development of facilities and processes for conversion to  plutonium oxide. DOE officials said that this fuel could also be disposed of  through other to-be-determined disposition paths. Currently, EM manages  the spent nuclear fuel that contains 7 MT of this surplus plutonium at  various locations throughout the country.

NNSA’s Long-Term Plutonium Oxide Production Plan Is Uncertain because of Two Key Issues

NNSA’s 2018 conceptual plan calls for converting 26.2 MT of surplus  plutonium into oxide by 2045. In September 2019, NNSA approved the  production of about 1.2 MT of plutonium oxide through 2025 at LANL.  However, plans for converting additional surplus plutonium into plutonium  oxide are uncertain primarily because of two issues. These issues are (1)  NNSA’s plans for new pit production, which are still in development and  which will also take place at LANL; and (2) issues surrounding the  agency’s ability to ship newly produced plutonium oxide for dilution to  DOE’s Savannah River Site (SRS) in South Carolina. According to  agency officials, NNSA and DOE are taking several actions that, if  successfully implemented, are designed to allow NNSA to meet its long- term plutonium oxide production goals. These actions include continuing  to review plutonium oxide and pit production plans, increasing plutonium  storage at LANL, reducing the amount of SRS’s surplus plutonium, and  shipping the diluted plutonium from SRS to WIPP.

NNSA’s 2018 Conceptual Plan Would Increase Plutonium Oxide Production at LANL

NNSA’s 2018 conceptual plan called for expanding plutonium oxide  production capacity in PF-4 for the dilute and dispose strategy to achieve  production of 1.5 MT per year by 2033. NNSA planned to sustain this  rate of production at LANL for 12 years to convert a total of 26.2 MT of  pits to plutonium oxide before ramping down operations in 2045. The  agency’s 2018 conceptual plan estimated that this increased production  would cost approximately $5 billion over the life of the program. To  achieve the 1.5 MT annual production rate, NNSA planned to expand the  physical space of ARIES’s operations in PF-4 by about 50 percent,  install new equipment such as glove boxes, purchase additional  equipment, such as spare parts and new shipping containers, and hire  over 200 new staff. To accommodate the larger workforce, NNSA also  planned to construct a new employee entrance in PF-4.

In September 2019, NNSA approved a short-term plan to produce a total  of nearly 1.2 MT of plutonium oxide at PF-4 from 2019 through 2025. This  short-term plan closely matches the total plutonium oxide production  outlined in NNSA’s 2018 conceptual plan for the same time frame.

Two Key Issues May Affect NNSA’s Long-Term Plutonium Oxide Plans

In February 2019, NNSA officials said that they were reevaluating the  agency’s long-term plutonium oxide production goals in the 2018  conceptual plan because of two key issues. These issues are space  constraints relating to (1) the agency’s mission to produce new pits in PF- 4 and (2) requirements to remove plutonium from SRS. According to  agency officials, NNSA and DOE are taking several actions designed to allow NNSA to meet the long-term plutonium oxide production goals  described in its 2018 conceptual plan.

New Pit Production Could Impede Plutonium Oxide Production, but NNSA is Taking Some Actions to Address This Issue

As we reported in November 2018, NNSA officials said that a planned  nuclear weapons refurbishment and future warhead programs will require  the production of new pits. Almost all of the pits in the current U.S.  nuclear weapons stockpile were produced before 1990, according to a  May 2015 Congressional report. In May 2018, NNSA announced that it  intended to build 30 pits annually in PF-4 at LANL by 2026 and 50 pits  annually at the MFFF at SRS by 2030, under a plan to repurpose the  MFFF for pit production. According to an August 2019 LANL presentation  to potential subcontractors, this effort will include the installation of more  than 140 new gloveboxes or other enclosures in PF-4 and the  construction of more than 700,000 square feet of supporting infrastructure  (such as offices, a parking garage, and a cafeteria). The President’s  budget for fiscal year 2020 includes over $3 billion for this effort through  2024. In April 2019, the NNSA Administrator said meeting pit production  requirements was the agency’s highest infrastructure priority.

NNSA also may have to increase pit production at LANL beyond 30 pits  per year. For example, in May 2018 the Nuclear Weapons Council stated  that it was essential that NNSA provide resources for surge pit production  capacity in PF-4 at LANL until pit production is fully established at SRS.  In addition, the National Defense Authorization Act for fiscal year 2019  requires the Department of Defense and NNSA to contract with a  federally funded research and development center to conduct an  assessment of, among other things, a strategy for producing 80 pits per year at LANL. NNSA officials told us in February 2019 that as a result of  pit production requirements, the agency might need to use a portion of  the processing areas in PF-4 for pit production that the agency had  planned to use for plutonium oxide production. Pit production  requirements also may use more space in the high-security vault in PF-4  where plutonium must be temporarily stored. Also in February 2019,  NNSA officials said that PF-4’s high-security storage space is already  near full capacity and that pit production may demand storage space that  NNSA had planned to use for plutonium oxide production.

NNSA officials said that the agency is taking some actions that are  designed to address increasing both pit and plutonium oxide production in  PF-4. If successfully implemented, these actions are designed to allow  the program to meet the milestones described in the 2018 conceptual  plan, according to NNSA officials. These actions include:

Reviewing use of operational space in PF-4. LANL reported in  March 2019 that the requirement to produce 30 pits per year would  have no significant negative impact on plutonium oxide production.  However, LANL reported that a number of programs, including pit  production, were planning to increase operations in PF-4, placing  demands on the aging facility that could lead to more frequent  maintenance outages. In August 2019, NNSA officials responsible  for plutonium oxide production and pit production said they continue to  believe that increased oxide production and pit production can be  simultaneously accomplished in PF-4 but that they are continuing to  review the issue as the agency’s pit production plans evolve. In  NNSA’s comments on our report, the NNSA Administrator said the  agency was working to balance the needs of both missions. The  Administrator also noted that NNSA’s Office for Cost Estimating and  Program Evaluation will assess the effect of plutonium oxide  production on pit production as required by section 3120 of the  National Defense Authorization Act for fiscal year 2019. The  conference report accompanying the act also requires that we review  this assessment, which we will initiate in late 2019.

Increasing plutonium storage capacity. LANL also reported in  March 2019 that it planned to implement several mitigation measures  that would allow the storage of more plutonium oxide and other  materials in the PF-4 vault. In addition, DOE and NNSA have  “swapped” 1 MT of the declared surplus plutonium at SRS with 1 MT  of plutonium residues and other primarily non-pit plutonium already  stored in LANL’s PF-4 vault. NNSA officials said that the plutonium  residues and other primarily non-pit plutonium at LANL would be  considered surplus plutonium and would be converted to plutonium  oxide, requiring less storage space. Without these mitigation  measures, the PF-4 vault would fill up years earlier, according to  NNSA officials. NNSA officials said they believe the swap will increase  storage space through 2028, at which point LANL would need to ship  plutonium oxide to SRS or face a suspension of plutonium oxide  production.

Requirement to Remove Plutonium from SRS Could Impede Shipping Plutonium Oxide There, but NNSA is Taking Some Actions to Address This Issue

Storing quantities of plutonium oxide in PF-4’s high-security storage vault  is critical because, according to NNSA officials, it is not likely that NNSA  will ship plutonium oxide or other forms of plutonium to SRS until a  dispute with the state of South Carolina is resolved. Specifically, the  National Defense Authorization Act for fiscal year 2003 required DOE to  prepare a plan for the construction and operation of the MFFF at SRS so  that it could produce MOX fuel at an average rate of at least 1 MT per  year. As subsequently amended, the law provides that if DOE did not  meet this 1 MT production objective by January 1, 2014, then it was  required to remove 1 MT of defense plutonium from South Carolina by  January 1, 2016. If DOE missed that deadline, it was required to make  substantial payments to South Carolina until the removal was  completed. As NNSA faced delays and cost increases in constructing  the MFFF and began to reevaluate its surplus disposition strategy, South  Carolina sued DOE in February 2016 to begin removing plutonium from  the state and to begin to make payments to the state of up to $100 million  per year until the surplus plutonium is removed.

In December 2017, the court ordered DOE to remove 1 MT of plutonium  from South Carolina by 2020. In response, according to court filings,  NNSA moved 0.5 MT of plutonium from SRS to its Nevada National  Security Site prior to November 2018 and moved another 0.5 MT of  plutonium off-site in August 2019. DOE is still required by statue to  remove an amount of defense plutonium or defense plutonium material  equal to that which was transferred to SRS after April 15, 2002, but not  processed by the MOX facility by January 2022. The officials told us that  because of this continuing requirement and the threat of further lawsuits  by South Carolina, it was unlikely that NNSA could ship plutonium oxide  to SRS until the surplus plutonium at SRS is removed.

NNSA officials said that the agency is taking some actions designed to  address these issues. These actions include:  Increasing plutonium oxide production rates with a priority on  oxidizing plutonium material from SRS. NNSA officials said in  August 2019 that they are in discussions with LANL to increase the  short-term production of plutonium oxide to speed the removal of  surplus plutonium from South Carolina. According to NNSA officials,  NNSA and LANL are considering increasing plutonium oxide  production through 2025 beyond what is called for in their short-term  plan that the agency approved in September 2019. This would  involve shipping additional surplus plutonium metal from SRS to LANL  and prioritize converting this material to plutonium oxide. According  to agency officials, LANL would produce additional plutonium oxide  production by using new ARIES equipment installed in PF-4 in 2019.  To achieve this increased production, NNSA officials said that LANL  would need to hire 70 personnel through 2025 to operate ARIES.  Agency officials said that these steps would increase total plutonium  oxide production to approximately 2.1 MT through 2025, an increase  of nearly 1 MT over the short-term plan NNSA approved in September  2019.

Increasing dilution and disposal rates of the inventory of  plutonium oxide already at SRS. DOE and NNSA officials said that  they would also increase dilution of existing plutonium oxide at SRS  beyond what is called for in the 2018 conceptual plan to help reduce  the inventory of plutonium metal already there. In April 2019, NNSA  officials said their current dilution rate at SRS was about 20 kilograms  (0.02 MT) annually, but that they plan to increase that rate to 1.5 MT  by the late 2020s. Under its 2018 conceptual plan, NNSA had planned  to achieve that dilution rate by 2031, but the budget request for NNSA  for fiscal year 2020 shows that NNSA plans to complete installation of  the capability necessary to achieve that dilution rate by as early as  fiscal year 2028. The effort—known as the Surplus Plutonium  Disposition project—has an estimated cost range from $200 million to  $589 million. It includes removing unnecessary equipment from SRS,  accelerating the project’s construction schedule, installing long-lead  procurement items early in construction, and hiring and certifying  additional personnel. According to NNSA officials, this increase in  dilution capacity by 2028 would enable NNSA to begin shipping  plutonium oxide to SRS for dilution and disposal without suspending  plutonium oxide production at PF-4.

While NNSA is taking actions to address pit production and shipment  issues, the agency continues to work on refining the long-term plutonium  oxide production goals in its 2018 conceptual plan. However, NNSA  officials said that establishing firm long-term plutonium oxide production  plans now would be premature and that the agency would use the next  several years to balance plutonium oxide production, pit production, and  shipment issues as they refine long-term production plans.

We provided a draft of this report to NNSA and DOE for review and  comment. In its response to our draft report, reproduced in appendix V,  NNSA said that it and DOE are working to balance the needs of its dilute  and dispose program, which includes oxide production, and pit  production, as well as the need to remove plutonium from the state of  South Carolina. NNSA said, as noted in our report, that its Office for Cost  Estimating and Program Evaluation would assess the effects of increased  plutonium oxide production on pit production.

NNSA also said that even with delays in production of plutonium oxide,  the dilution and disposition of surplus plutonium will still be substantially  less expensive than if the agency had maintained its MOX fuel approach.  As stated in our report, we have a large body of work that has examined  the MOX fuel approach, NNSA’s management of the MOX project, and  DOE’s $17 billion cost estimate to complete the project, which we  assessed as being reliable.

In addition, NNSA provided us with technical comments and additional  documentation, which we incorporated into our report as appropriate.  Some of the information that NNSA provided helped clarify near-term  plutonium oxide production plans as well as the agency’s progress in  balancing the plutonium oxide production plans, pit production, and the  need to move plutonium out of the state of South Carolina. This  information is incorporated in our report and is reflected in the report’s  revised title.

We are sending copies of this report to the appropriate congressional  committees, the Secretary of Energy, and other interested parties. In  addition, this report is available at no charge on the GAO website at  http://www.gao.gov.

If you or your staff members have questions about this report, please  contact me at (202) 512-3841 or trimbled@gao.gov. Contact points for  our Offices of Congressional Relations and Public Affairs may be found  on the last page of this report. GAO staff who made key contributions to  this report are listed in appendix VI.

Our report (1) determines the amount of surplus plutonium in the  Department of Energy’s (DOE) inventory that could be converted to  plutonium oxide for dilution and disposal and (2) examines DOE’s  capacity to produce plutonium oxide.

To determine the amount of surplus plutonium in DOE’s inventory that  could be converted to plutonium oxide for dilution and disposal, we  reviewed relevant DOE documents and interviewed officials from DOE,  including from DOE’s National Nuclear Security Administration (NNSA)  and DOE’s Office of Environmental Management (EM), on the amounts  and forms of surplus plutonium in DOE’s inventory that would require  conversion to an oxide prior to final disposition. Our review included  DOE’s plans for converting surplus plutonium to plutonium oxide  beginning in 1997, when DOE first decided to convert surplus plutonium  to plutonium oxide for disposition. We also visited the Los Alamos  National Laboratory (LANL) in New Mexico to review documentation and  interview officials in the Surplus Plutonium Disposition Program for  information on past and current inventories of surplus plutonium. NNSA’s  Advanced Recovery and Integrated Extraction System (ARIES), the  program that currently converts surplus plutonium to plutonium oxide,  resides in Plutonium Facility-4 (PF-4) at LANL.

To examine DOE’s capacity to produce plutonium oxide, we reviewed  relevant DOE documents and interviewed officials from DOE, including  from NNSA and EM, on the status of plutonium oxide production in PF-4  and at DOE’s Savannah River Site, where surplus plutonium was  converted to plutonium oxide over a 2 1/2-year period. We reviewed  relevant DOE documents and interviewed officials from DOE, including  from NNSA and EM, on their plans. For example, we reviewed records of  decision and environmental impact statements that DOE issued during its  management of the Surplus Plutonium Disposition Program. We reviewed  planning documents related to the dilute and dispose strategy, including  DOE’s life-cycle cost estimate and supporting documents covering issues  such as time frames and conversion rates. We visited the ARIES program  in PF-4 in January 2018 to review documentation and conduct interviews  with officials responsible for plutonium oxide production and the planned  expansion of plutonium oxide production. The site visit included a tour of  PF-4, ARIES and its operations, and potential spaces in PF-4 for  expansion of ARIES operations for converting surplus plutonium metal to  oxide.

Appendix II: Timeline of the Changes to Department of Energy (DOE) Disposition Strategies under the Surplus Plutonium Disposition Program

DOE first established the Surplus Plutonium Disposition Program in 1997  to dispose of surplus, weapons-usable plutonium at the end of the Cold  War. As of April 2019, the United States has declared a total of 61.5  metric tons (MT) of plutonium as surplus to defense needs. DOE has  disposed of 3.2 MT of surplus plutonium at the Waste Isolation Pilot Plant  (WIPP), an underground repository for transuranic waste located near  Carlsbad, New Mexico, and is in the process of disposing of an additional  1.1 MT of surplus plutonium. This leaves 57.2 MT of surplus plutonium in  its inventory, as of May 2019. The table below shows the timeline of  changes to DOE strategies for managing surplus plutonium for final  disposition.

Appendix III: Timeline of Key Events Concerning the Department of Energy’s (DOE) Surplus Plutonium Disposition Program

1997 - DOE announces the Surplus Plutonium Disposition Plan,  including the Mixed Oxide Fuel Fabrication Facility (MFFF).

2000 - The United States and Russia enter into the Plutonium  Management and Disposition Agreement (PMDA), each agreeing to  dispose of at least 34 metric tons (MT) of plutonium at a rate of at  least 2 MT per year.

2000 - DOE announced it will construct the MFFF.

2002 - The National Defense Authorization Act for fiscal year 2003  requires DOE to prepare a plan for the construction and operation of  the MFFF at the Savannah River Site in South Carolina and requires,  among other things, that DOE remove 1 MT of plutonium from South  Carolina by January 1, 2011, if mixed oxide (MOX) production  objectives of an average rate of at least 1 MT per year were not  achieved by January 1, 2009. Failure to meet these deadlines would  require DOE to make substantial annual payments to South Carolina.

2005 – The Energy and Water Development Appropriations Act for  Fiscal Year 2006 extends the original plutonium production and  removal deadlines by 3 years (thus making the 1 MT plutonium  production deadline January 1, 2012, and removal deadline January  1, 2014).

2014 – The National Defense Authorization Act for fiscal year 2015  requires DOE to issue a report that would study the plan for the MFFF  as well as possible alternatives to the MFFF.

2015 - The National Defense Authorization Act for Fiscal Year 2016  requires DOE to carry out an analysis of alternatives for the Surplus  Plutonium Disposition Program.

2015 and 2017 - Explanatory statements accompanying fiscal years  2016 and 2017 appropriations legislation contained specific direction  to explore design issues associated with the dilute and dispose  alternative.

2016 - South Carolina sues DOE in federal district court, contending  that DOE failed to meet the MOX-related statutory deadlines. South  Carolina sought monetary relief and an injunction compelling the  federal government to remove 1 MT of plutonium from the state.

2016 - DOE issues a Record of Decision stating that it would remove  plutonium from South Carolina using the dilute and dispose strategy.

2017 - Federal district court issues an injunction ordering DOE to  remove 1 MT of plutonium from South Carolina and ordering the  parties to negotiate a new deadline.

2017 - The National Defense Authorization Act for Fiscal Year 2018  allowed DOE to terminate construction of MFFF if, among other  things, DOE identified an alternative that would cost less than half of  the MOX fuel strategy.

2017 - South Carolina and DOE fail to agree on a deadline for  removing 1 MT of plutonium from the state, so in December the court  imposes a deadline of January 1, 2020.

2018 - Federal appellate court rejects DOE’s appeal of the district  court’s order to remove 1 MT of plutonium from South Carolina by  January 1, 2020.

2018 - DOE terminates the MOX contract for the government’s  convenience.

2019 – DOE acknowledges that it had shipped 0.5 MT of plutonium  from South Carolina to Nevada sometime before November 2018 and  shipped an additional 0.5 MT out of South Carolina to another state  sometime before August 2019.

Appendix IV: Timeline of Key Events Relating to a High-Level Waste Repository for Disposing of Certain Surplus Plutonium

The Nuclear Waste Policy Act of 1982 directed, among other things, that  DOE study sites for a repository and that the President evaluate the  capacity for the disposal of high-level waste resulting from atomic energy  defense activities at one or more repositories developed for the disposal  of commercial used (spent) nuclear fuel. In 1985, President Reagan  found that there was no basis to conclude that a separate defense high- level waste repository was required. Table 2 shows the changes in plans  for developing a high-level waste repository from 2002 through 2018.

Appendix V: Comments from the Department of Energy

Appendix VI: GAO Contact and Staff Acknowledgments

In addition to the individual named above, the following individuals made  contributions to this report: Jonathan Gill (Assistant Director); Robert  Sánchez (Analyst in Charge); Antoinette Capaccio; Robert (Scott)  Fletcher; Cindy Gilbert; Richard Johnson; Sheryl Stein; Sara Sullivan; and  Curtis (Wade) Tanner.

The National Nuclear Security Administration manages 57.2 metric tons of surplus plutonium. NNSA's plan was to:

Convert much of it into a plutonium oxide powder in New Mexico

Ship the powder to South Carolina for dilution

Ship diluted oxide back to New Mexico for disposal

These plans are uncertain because of competing demands at the conversion facility. Also, shipments to South Carolina may be delayed because NNSA is prioritizing plutonium removal from the state in order to meet a legal requirement. NNSA officials said they are working on addressing these issues, for example, by speeding up plutonium shipments out of South Carolina.