The United States Plutonium Balance, 1944 - 2009

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Rocky Flats Site 1995 Rocky Flats Site 2005 Rocky Flats Site 1995 An update of Plutonium: The First 50 Years,

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This report updates Plutonium: The first 50 years which was released by the U.S. Department of Energy (DOE) in 1996. The topic of both reports is plutonium, sometimes referred to as Pu-239, which is capable of sustaining a nuclear chain reaction and is used in nuclear weapons and for nuclear power production. The measures of plutonium are 2424 are topics of this report. The plutonium discussed is owned by the DOE including that in the possession of the Department of Defense. Accordingly, plutonium in the civilian nuclear fuel cycle is not addressed unless it is owned by the DOE. Inventory refers to the plutonium maintained under nuclear material control and accountability, whereas waste estimates refer to plutonium tracked solely for environmental, safety, and 1 Element weight typically includes the isotopes 238, 239, 240, 241, and 242, with the predominate contributors being 239 and 240. 2 One metric ton is 2,205 pounds, and one kilogram is approximately 2.2 pounds. 3 Plutonium-238 has a Pu-238 content of greater than 10% by weight of total plutonium. 4 Plutonium-242 has a Pu-242 content of greater than 20% by weight of total plutonium.

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Table of Contents Table of Contents ............................................................................................................... iii List of Figures .................................................................................................................... iv List of Tables ...................................................................................................................... v 4. Plutonium Mass Balance............................................................................................... 11

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List of Figures Figure 1 U.S. Plutonium: Where it Came From and Current Balance Statement ………...4 Figure 2 Plutonium Sites Referenced in this Report ........................................................... 8 Figure 3 Discards to Waste 1995 through 2009................................................................ 12 Figure 4 Revised Estimates of Plutonium Shipped to Idaho from Rocky Flats ............... 19

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List of Tables Table 1 Location of the U.S. Plutonium Accountable Inventory ....................................... 9 Table 2 U.S. Plutonium: Acquisitions, Removals, and Inventory .................................... 11 Table 3 Excess Weapon-Grade Plutonium ....................................................................... 14 Table 4 Plutonium in Waste Estimates ............................................................................. 16 Table 5 Plutonium Disposed at WIPP .............................................................................. 17 Table 6 Hanford Waste Estimates 2009............................................................................ 20 Table 7 Revisions to Rocky Flats Plutonium in Waste..................................................... 22

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The Department of Energy’s 1996 publication, Plutonium: The First 50 Years, DOE/DP0137, related to the production, acquisition, and utilization of plutonium from the mid1940s through 1994. The 1996 report was constructed from both original paper records dating back to the early 1940s and electronic data collected regularly since the late 1960s as part of the Nuclear Materials Management and Safeguards System (NMMSS). The 1996 report identified that: The combined DOE and DoD accountable 1994 plutonium inventory was 99.5 metric tons (MT), which included a pooled 66.1 MT for the Pantex Plant near Amarillo, Texas, and the U.S. nuclear weapons stockpile; The U.S. plutonium balance included 2.8 MT of inventory differences, equating to 2.5 percent of the total plutonium production; A total of 38.2 MT of accountable weapon-grade plutonium was declared surplus to defense needs and would never be used to build nuclear weapons; and, The amount of plutonium contained in waste was 3.9 MT located at nine different This report updates 1994 data through 2009. The four most significant changes since 1994 include: (a) the completion of cleanup activities at the Rocky Flats Plant in 2005; (b) material consolidation and disposition activities, especially shipments from Hanford to the Savannah River Site; (c) the 2007 declaration of an additional 9.0 MT of weaponsgrade plutonium to be surplus to defense needs in the coming decades; and (d) the opening of the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico in 1999. These interrelated factors have not only resulted in decreases to total inventory and inventory differences but also increases in both surplus materials and materials written off the accountable inventory as waste. Figure 1 is a graphical summary of these interrelated factors spanning the fifteen years between the two reports.

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This report also contains important revisions to previously reported data. The most significant revisions include increases in waste estimates for both Hanford and Idaho, based on improvements in waste characterization and reviews of historical records. These developments, especially the increases in waste, have led the DOE to prepare this update to the 1996 plutonium report. As a consequence, whereas waste was only an appendix in the 1996 report, it is one of the primary focuses of this update. This report documents that as of September 30, 2009: The plutonium inventory, maintained under nuclear material control and accountability, is 95.4 MT, a 4.1 MT (4 %) decrease to the 1994 inventory. The 95.4 MT total includes a combined Pantex and nuclear weapons stockpile of 67.7 MT. The most important factor for the reduction in inventory was the reclassification of process residues originally set aside for plutonium recovery as waste. Of the 4.1 MT reduction, 3.5 MT (85 %) came from Rocky Flats residues sent to WIPP for disposition; The cumulative inventory difference for accountable plutonium is 2.4 MT, a 0.4 MT (14 %) decrease to the 2.8 MT made public in the 1996 plutonium report. The 0.4 MT decrease in the cumulative inventory difference is attributed to materials recovered during de-inventorying and closure activities at Rocky Flats (0.3 MT) and Hanford (0.1 MT). Of the current 2.4 MT of inventory difference, 1.1 MT (46%) is at Hanford and 0.9 MT (38%) at Rocky Flats. A large portion of the remaining 2.4 MT cumulative inventory difference appears to be explained by understated removals from inventory to waste; Plutonium surplus to defense needs is now 43.4 MT, a 5.2 MT (14 %) increase to the 1994 declaration; and The plutonium estimated in waste estimate is 9.7 MT, a 5.8 MT (149%) increase to the 1994 inventory of 3.9 MT. The 5.8 MT increase is attributed to: 4.4 MT (76%) in new discards from the accountable inventory; 0.8 MT (330%) increase in Rocky Flats solid waste generated prior to 1970; 0.4 MT (84%) increase in

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Hanford high level waste tank estimates; 0.1 MT in solid waste at a commercial low-level radioactive disposal facility not included in the 1996 report,5 and 0.1 MT from other sites. The information contained herein is current as of September 2009 and is based on the best available information. There remain uncertainties about how much plutonium was actually produced, processed, and discarded to waste, especially for the period from the mid-1940s to 1970 before advances in nuclear material measurement systems and computer-aided tools to assist in the analysis of nuclear material accounting data. These uncertainties are reflected in the 2.4 MT cumulative inventory difference. This uncertainty applies especially to waste estimates, where quantities will continue to change and evolve as waste processing and characterization are performed as part of environmental cleanup activities. Consequently, information contained herein is subject to change as additional data become available during facility cleanout and waste 5 The 1996 plutonium history report included only the plutonium in waste that the DOE manages at its facilities; wastes at commercially operated facilities on leased DOE land were not included.

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Figure 1 U.S. Plutonium: Where it Came From and Current Balance Statement

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In February of 1996 the Department of Energy released the report Plutonium: The First 50 Years. Commonly referred to as either the plutonium history report or the 1994 declaration, the 1996 report summarized U.S. plutonium production, acquisition, and utilization from the beginning of activities in 1944 through 1994. The report was produced at the request of the Secretary of Energy to support President Clinton’s goal for greater openness and transparency in government. The philosophy behind the release of the plutonium history report recognized that transparency is essential to public accountability and trust. It was believed that the report would aid discussions of plutonium storage, safety, and security with stakeholders as well as encourage other nations to declassify and release similar information. The data in the plutonium history report offered stakeholders increased opportunities to participate in policymaking by providing the benefits of their collective expertise and information to governmental leadership. Most importantly, the goal of increased governmental openness was realized without either compromising national security or aiding nuclear The 1994 declaration is now more than 16 years old. Since the release of the 1996 report, significant changes in both location and quantity of U.S. plutonium have occurred. Changes in location include closure of the Rocky Flats Plant in 2005 and the consolidation of plutonium stocks to the Savannah River Site in South Carolina from the Hanford Site and the Lawrence Livermore and Los Alamos National Laboratories. At the same time, significant quantities of plutonium, originally set aside for future recovery, were deemed surplus and made available for disposal in 2000 at the then newly opened Waste Isolation Pilot Plant in New Mexico. After more than a decade and a half, significant interest in this topic remains. The aim of this publication is to provide, in a transparent manner, comprehensive and up-to-date data

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to regulators, public interest organizations, and the general public. Knowledge of the current U.S. plutonium balance and the locations of these materials is needed to understand the Department’s plutonium storage, safety, and security strategies. The information contained in this report updates the 1994 data through 2009. Over the 65-year history of the U.S. nuclear program, there have been many different organizations and facilities involved in producing, processing, utilizing, and regulating6 nuclear materials. From the beginning of the nuclear program in the 1940s through 1954, the U.S. effort was primarily military in character. During this period, all special nuclear material7 was government property held by contractors operating government-owned facilities. In 1954, the Atomic Energy Act of 1946 was amended to allow civilian peaceful use, though not ownership, of special nuclear material. It was not until the mid-1960s that private ownership of special nuclear material was permitted, with a further amendment to the Atomic Energy Act. The Energy Reorganization Act of 1974 created the Nuclear Regulatory Commission (NRC). The NRC began operations in 1975 to regulate several important areas involving privatelyowned nuclear materials, including nuclear material control and accountability, reactor safety, plant siting, and environmental protection. In the U.S., plutonium was both produced and expended in nuclear reactors. It was separated/recovered in processing facilities from irradiated reactor fuel and then blended into fuel elements as new reactor fuel or utilized in many different forms for energy, medical, and national defense purposes. Residues from these operations were processed, and the plutonium recovered and recycled. Plutonium wastes that were either economically or technically unrecoverable were stored for future disposal. It was not 6 The regulating organizations were the U.S. Army Corps of Engineers Manhattan Engineering District (1940-1947), the Atomic Energy Commission (1947-1975), the Energy Research and Development Administration (1975-1977), and DOE (1977 to present). 7 Special nuclear material is defined by the Atomic Energy Act and includes plutonium and uranium enriched in the U-235 isotope or the U-233 isotope.

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until 1999 that the U.S. opened a facility to permanently dispose of transuranic waste8 including plutonium waste from the research on and production of nuclear weapons. The facilities discussed in this update are shown in Figure 2. Included in the figure is background information for nine principal facilities including mission, location, size, operating dates, status, plutonium inventory, and waste estimates. 8 Radioactive waste that contains more than 100 nCi/g of alpha-emitting isotopes with atomic numbers greater than 92 and half-lives greater than 20 years.

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The 1996 plutonium history report acknowledged that the September 30, 1994 DOE/DoD plutonium inventory was 99.5 MT (Table 1). At that time, the 99.5 MT was composed of 85.0 MT weapons grade (less than 7% Pu-240), 13.2 MT fuel grade (7 to less than 19% Pu-240), and 1.3 MT power reactor grade plutonium (19% and greater Pu-240). Table 1 also shows that the September 30, 2009 plutonium inventory was 95.4 MT, a 4.1 MT (4%) decrease to the 1994 inventory. The 95.4 MT was composed of 81.3 MT weapons grade, 12.7 MT fuel grade, and 1.4 MT power reactor grade plutonium. Table 1 Location of the U.S. Plutonium Accountable Inventory (MT) DoD and Pantex Plant 66.1 67.7 1.6 Rocky Flats Plant 12.7 0.0 -12.7 Savannah River Site 2.0 12.0 10.0 The 4.1 MT reduction in inventory from 1994 to 2009 was primarily attributable to the closure in 2005 of the Rocky Flats Plant and material disposition activities, especially the removal of plutonium from the accountable inventory as waste and shipped to the WIPP. The majority of the government plutonium inventory (71% compared to 66% in 1994) still resides at DoD and Pantex. 9 Increases in inventory reflect consolidation of plutonium pits at Pantex and surplus non-pit plutonium at the Savannah River Site per record of decision for the storage and disposition of weapons-usable fissile materials final programmatic environmental impact statement. 10 Idaho National Laboratory, which includes the Argonne National Laboratory-West. 11 The quantities are element weight plutonium, which typically includes the isotopes 238, 239, 240, 241, and 242, with the predominant contributors being 239 and 240.

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The largest inventory decrease occurred at Rocky Flats, where 3.5 MT of its 12.7 MT inventory was shipped to WIPP for disposition, and the remaining 9.2 MT was sent to other DOE facilities as part of shutdown and material consolidation activities. The largest increase in inventory (500%) was at Savannah River, reflecting the site’s missions to: (a) store surplus plutonium from Hanford, Rocky Flats, Los Alamos National Laboratory, and Lawrence Livermore National Laboratory as part of the plutonium consolidation and disposition program, (b) convert surplus nuclear weapons components to commercial nuclear mixed oxide fuel, and (c) store irradiated nuclear fuel elements from foreign and domestic power and research reactors. Quantities in Table 1 are owned by the DOE and include plutonium in the possession of the DoD. Plutonium in the civilian nuclear fuel cycle is not included in the totals unless the material is owned by the DOE. DOE-owned material in the civilian nuclear fuel cycle is included in the Other Sites category. Quantities in Table 1 comprise plutonium that is maintained under nuclear material control and accountability (i.e., the accountable inventory). The accountable inventory is tracked for safeguards and security reasons. It is important to note that the quantities in Table 1 do not include plutonium that has been removed from the accountable inventory as waste (for example, plutonium at WIPP). Waste estimates are tracked for environmental, safety, and health reasons and are discussed separately in Section 6 of this report.

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4. Plutonium Mass Balance From 1944 to 2009, DOE and its predecessor organizations produced and acquired a total of 111.7 MT of plutonium (Table 2). During the same period, 14.0 MT was removed from the inventory. Classified transactions and rounding account for a positive 0.1 MT, and the DOE cumulative inventory difference through 2009 was 2.4 MT. These four factors (total receipts, minus total removals, plus classified transactions and rounding, minus the cumulative inventory difference) yield a September 2009 inventory of 95.4 MT plutonium, a 4.1 MT reduction to the 1994 inventory of 99.5 MT. Table 2 U.S. Plutonium: Acquisitions, Removals, and Inventory (MT) From Foreign Countries 5.7 5.8 0.1 Expended in Wartime & Tests 3.4 …