Proliferation resistance criteria for fissile material disposition

International Nuclear Information System (INIS)

Close, D.A.; Fearey, B.L.; Markin, J.T.; Rutherford, D.A.; Duggan, R.A.; Jaeger, C.D.; Mangan, D.L.; Moya, R.W.; Moore, L.R.; Strait, R.S.

1995-04-01

The 1994 National Academy of Sciences study open-quotes Management and Disposition of Excess Weapons Plutoniumclose quotes defined options for reducing the national and international proliferation risks of materials declared excess to the nuclear weapons program. This report proposes criteria for assessing the proliferation resistance of these options. The criteria are general, encompassing all stages of the disposition process from storage through intermediate processing to final disposition including the facilities, processing technologies and materials, the level of safeguards for these materials, and the national/subnational threat to the materials

Nonproliferation and arms control assessment of weapons-usable fissile material storage and excess plutonium disposition alternatives

International Nuclear Information System (INIS)

1997-01-01

This report has been prepared by the Department of Energy's Office of Arms Control and Nonproliferation (DOE-NN) with support from the Office of Fissile Materials Disposition (DOE-MD). Its purpose is to analyze the nonproliferation and arms reduction implications of the alternatives for storage of plutonium and HEU, and disposition of excess plutonium, to aid policymakers and the public in making final decisions. While this assessment describes the benefits and risks associated with each option, it does not attempt to rank order the options or choose which ones are best. It does, however, identify steps which could maximize the benefits and mitigate any vulnerabilities of the various alternatives under consideration

Proliferation resistance criteria for fissile material disposition issues

International Nuclear Information System (INIS)

Rutherford, D.A.; Fearey, B.L.; Markin, J.T.; Close, D.A.; Tolk, K.M.; Mangan, D.L.; Moore, L.

1995-01-01

The 1994 National Acdaemy of Sciences study ''Management and Disposition of Excess Weapons Plutonium'' defined options for reducing the national and international proliferation risks of materials declared excess to the nuclear weapons program. This paper proposes criteria for assessing the proliferation resistance of these options as well defining the ''Standards'' from the report. The criteria are general, encompassing all stages of the disposition process from storage through intermediate processing to final disposition including the facilities, processing technologies and materials, the level of safeguards for these materials, and the national/subnational threat to the materials

Nonproliferation and arms control assessment of weapons-usable fissile material storage and excess plutonium disposition alternatives

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-01-01

This report has been prepared by the Department of Energy`s Office of Arms Control and Nonproliferation (DOE-NN) with support from the Office of Fissile Materials Disposition (DOE-MD). Its purpose is to analyze the nonproliferation and arms reduction implications of the alternatives for storage of plutonium and HEU, and disposition of excess plutonium, to aid policymakers and the public in making final decisions. While this assessment describes the benefits and risks associated with each option, it does not attempt to rank order the options or choose which ones are best. It does, however, identify steps which could maximize the benefits and mitigate any vulnerabilities of the various alternatives under consideration.

Fissile Material Disposition Program: Deep borehole disposal Facility PEIS date input report for immobilized disposal. Immobilized disposal of plutonium in coated ceramic pellets in grout with canisters. Version 3.0

International Nuclear Information System (INIS)

Wijesinghe, A.M.; Shaffer, R.J.

1996-01-01

Following President Clinton's Non-Proliferation Initiative, launched in September, 1993, an Interagency Working Group (IWG) was established to conduct a comprehensive review of the options for the disposition of weapons-usable fissile materials from nuclear weapons dismantlement activities in the United States and the former Soviet Union. The IWG review process will consider technical, nonproliferation, environmental budgetary, and economic considerations in the disposal of plutonium. The IWG is co-chaired by the White House Office of Science and Technology Policy and the National Security Council. The Department of Energy (DOE) is directly responsible for the management, storage, and disposition of all weapons-usable fissile material. The Department of Energy has been directed to prepare a comprehensive review of long-term options for Surplus Fissile Material (SFM) disposition, taking into account technical, nonproliferation, environmental, budgetary, and economic considerations

Fissile Material Disposition Program: Deep borehole disposal Facility PEIS date input report for immobilized disposal. Immobilized disposal of plutonium in coated ceramic pellets in grout with canisters. Version 3.0

Energy Technology Data Exchange (ETDEWEB)

Wijesinghe, A.M.; Shaffer, R.J.

1996-01-15

Following President Clinton`s Non-Proliferation Initiative, launched in September, 1993, an Interagency Working Group (IWG) was established to conduct a comprehensive review of the options for the disposition of weapons-usable fissile materials from nuclear weapons dismantlement activities in the United States and the former Soviet Union. The IWG review process will consider technical, nonproliferation, environmental budgetary, and economic considerations in the disposal of plutonium. The IWG is co-chaired by the White House Office of Science and Technology Policy and the National Security Council. The Department of Energy (DOE) is directly responsible for the management, storage, and disposition of all weapons-usable fissile material. The Department of Energy has been directed to prepare a comprehensive review of long-term options for Surplus Fissile Material (SFM) disposition, taking into account technical, nonproliferation, environmental, budgetary, and economic considerations.

Fissile material disposition and proliferation risk

Energy Technology Data Exchange (ETDEWEB)

Dreicer, J.S.; Rutherford, D.A. [Los Alamos National Lab., NM (United States). NIS Div.

1996-05-01

The proliferation risk of a facility is dependent on the material attractiveness, level of safeguards, and physical protection applied to the material in conjunction with an assessment of the impact of the socioeconomic circumstances and threat environment. Proliferation risk is a complementary extension of proliferation resistance. The authors believe a better determination of nuclear material proliferation can be achieved by establishing the proliferation risk for facilities that contain nuclear material. Developing a method that incorporates the socioeconomic circumstances and threat environment inherent to each country enables a global proliferation assessment. In order to effectively reduce the nuclear danger, a broadly based set of criteria is needed that provides the capability to relatively assess a wide range of disposition options/facilities in different countries and still ensure a global decrease in proliferation risk for plutonium.

Fissile material disposition and proliferation risk

International Nuclear Information System (INIS)

Dreicer, J.S.; Rutherford, D.A.

1996-01-01

The proliferation risk of a facility is dependent on the material attractiveness, level of safeguards, and physical protection applied to the material in conjunction with an assessment of the impact of the socioeconomic circumstances and threat environment. Proliferation risk is a complementary extension of proliferation resistance. The authors believe a better determination of nuclear material proliferation can be achieved by establishing the proliferation risk for facilities that contain nuclear material. Developing a method that incorporates the socioeconomic circumstances and threat environment inherent to each country enables a global proliferation assessment. In order to effectively reduce the nuclear danger, a broadly based set of criteria is needed that provides the capability to relatively assess a wide range of disposition options/facilities in different countries and still ensure a global decrease in proliferation risk for plutonium

Disposition of excess fissile materials in deep boreholes

International Nuclear Information System (INIS)

Halsey, W.G.; Danker, W.; Morley, R.

1995-09-01

As a result of recent changes throughout the world, a substantial inventory of excess separated plutonium is expected to result from dismantlement of US nuclear weapons. The safe and secure management and eventual disposition of this plutonium, and of a similar inventory in Russia, is a high priority. A variety of options (both interim and permanent) are under consideration to manage this material. The permanent solutions can be categorized into two broad groups: direct disposal and utilization. Plutonium utilization options have in common the generation of high-level radioactive waste which will be disposed of in a mined geologic disposal system to be developed for spent reactor fuel and defense high level waste. Other final disposition forms, such as plutonium metal, plutonium oxide and plutonium immobilized without high-level radiation sources may be better suited to placement in a custom facility. This paper discusses a leading candidate for such a facility; deep (several kilometer) borehole disposition. The deep borehole disposition concept involves placing excess plutonium deep into old stable rock formations with little free water present. The safety argument centers around ancient groundwater indicating lack of migration, and thus no expected communication with the accessible environment until the plutonium has decayed

Plutonium-bearing materials feed report for the DOE Fissile Materials Disposition Program alternatives

International Nuclear Information System (INIS)

Brough, W.G.; Boerigter, S.T.

1995-01-01

This report has identified all plutonium currently excess to DOE Defense Programs under current planning assumptions. A number of material categories win clearly fan within the scope of the MD (Materials Disposition) program, but the fate of the other categories are unknown at the present time. MD planning requires that estimates be made of those materials likely to be considered for disposition actions so that bounding cases for the PEIS (Programmatic Environmental Impact Statement) can be determined and so that processing which may be required can be identified in considering the various alternatives. A systematic analysis of the various alternatives in reachmg the preferred alternative requires an understanding of the possible range of values which may be taken by the various categories of feed materials. One table identifies the current total inventories excess to Defense Program planning needs and represents the bounding total of Pu which may become part of the MD disposition effort for all materials, except site return weapons. The other categories, principally irradiated fuel, rich scrap, and lean scrap, are discussed. Another table summarizes the ranges and expected quantities of Pu which could become the responsibility of the MD program. These values are to be used for assessing the impact of the various alternatives and for scaling operations to assess PEIS impact. Determination of the actual materials to be included in the disposition program will be done later

The environmental assessment of nuclear materials disposition options: A transportation perspective

International Nuclear Information System (INIS)

Wilson, R.K.; Clauss, D.B.; Moyer, J.W.

1994-01-01

The US Department of Energy has undertaken a program to evaluate and select options for the long-term storage and disposition of fissile materials declared surplus to defense needs as a result of the end of the Cold War. The transport of surplus fissile material will be an important and highly visible aspect of the environmental impact studies and other planning documents required for implementation of the disposition options. This report defines the roles and requirements for transportation of fissile materials in the program, and discusses an existing methodology for determining the environmental impact in terms of risk. While it will be some time before specific alternatives are chosen that will permit the completion of detailed risk calculations, the analytical models for performing the probabilistic risk assessments already exist with much of the supporting data related to the transportation system. This report summarizes the various types of data required and identifies sources for that data

Disposition scenarios and safeguardability of fissile materials under START Treaty

International Nuclear Information System (INIS)

Pillay, K.K.S.

1993-01-01

Under the Strategic Arms Reduction Treaty (START-I) signed in 1991 and the Lisbon Protocol of 1992, a large inventory of fissile materials will be removed from the weapons fuel cycles of the United States and the Former Soviet Union (FSU). The Lisbon Protocol calls for Ukraine, Kazakstan, and Byelarus to become nonnuclear members of the treaty and for Russia to assume the responsibility of the treaty as a nuclear weapons state. In addition, the START-II Treaty, which was signed in 1993 by the United States and Russia, further reduces deployed nuclear warheads and adds to the inventory of excess special nuclear materials (SNM). Because storage of in-tact warheads has the potential for a open-quotes breakout,close quotes it would be desirable to dismantle the warheads and properly dispose of the SNMs under appropriate safeguards to prevent their reentry into the weapons fuel cycle. The SNM recovered from dismantled warheads can be disposed of in several ways, and the final choices may be up to the country having the title to the SNM. Current plans are to store them indefinitely, leaving serious safeguards concerns. Recognizing that the underlying objective of these treaties is to prevent the fissile materials from reentering the weapons fuel cycle, it is necessary to establish a verifiable disposal scheme that includes safeguards requirements. This paper identifies some realistic scenarios for the disposal of SNM from the weapons fuel cycle and examines the safeguardability of those scenarios

Disposition Options for Uranium-233

International Nuclear Information System (INIS)

Beahm, E.C.; Dole, L.R.; Forsberg, C.W.; Icenhour, A.S.; Storch, S.N.

1999-01-01

The U.S. Department of Energy (DOE) Fissile Materials Disposition Program (MD), in support of the U.S. arms-control and nonproliferation policies, has initiated a program to disposition surplus weapons-usable fissile material by making it inaccessible and unattractive for use in nuclear weapons. Weapons-usable fissile materials include plutonium, high-enriched uranium (HEU), and uranium-233 (sup 233)U. In support of this program, Oak Ridge National Laboratory led DOE's contractor efforts to identify and characterize options for the long-term storage and disposal of excess (sup 233)U. Five storage and 17 disposal options were identified and are described herein

New glass material oxidation and dissolution system facility: Direct conversion of surplus fissile materials, spent nuclear fuel, and other material to high-level-waste glass. Storage and disposition of weapons-usable fissile materials programmatic environmental impact statement data report: Predecisional draft

International Nuclear Information System (INIS)

Forsberg, C.W.; Elam, K.R.; Reich, W.J.

1995-01-01

With the end of the Cold War, countries have excess plutonium and other materials from the reductions in inventories of nuclear weapons. It has been recommended that these surplus fissile materials (SFMs) be processed so that they are no more accessible than plutonium in spent nuclear fuel (SNF). This SNF standard, if adopted worldwide, would prevent rapid recovery of SFMs for the manufacture of nuclear weapons. This report provides for the PEIS the necessary input data on a new method for the disposition of SFMs: the simultaneous conversion of SFMs, SNF, and other highly radioactive materials into high-level-waste (HLW) glass. The SFMs include plutonium, neptunium, americium, and 233 U. The primary SFM is plutonium. The preferred SNF is degraded SNF, which may require processing before it can be accepted by a geological repository for disposal. The primary form of this SNF is Hanford-N SNF with preirradiation uranium enrichments between 0.95 and 1.08%. The final product is a plutonium, low-enriched-uranium, HLW, borosilicate glass for disposition in a geological repository. The proposed conversion process is the Glass Material Oxidation and Dissolution System (GMODS), which is a new process. The initial analysis of the GMODS process indicates that a MODS facility for this application would be similar in size and environmental impact to the Defense Waste Processing Facility (DWPF) at the Savannah River Site. Because of this, the detailed information available on DWPF was used as the basis for much of the GMODS input into the SFMs PEIS

Highly enriched uranium (HEU) storage and disposition program plan

International Nuclear Information System (INIS)

Arms, W.M.; Everitt, D.A.; O'Dell, C.L.

1995-01-01

Recent changes in international relations and other changes in national priorities have profoundly affected the management of weapons-usable fissile materials within the United States (US). The nuclear weapon stockpile reductions agreed to by the US and Russia have reduced the national security requirements for these fissile materials. National policies outlined by the US President seek to prevent the accumulation of nuclear weapon stockpiles of plutonium (Pu) and HEU, and to ensure that these materials are subjected to the highest standards of safety, security and international accountability. The purpose of the Highly Enriched Uranium (HEU) Storage and Disposition Program Plan is to define and establish a planned approach for storage of all HEU and disposition of surplus HEU in support of the US Department of Energy (DOE) Fissile Material Disposition Program. Elements Of this Plan, which are specific to HEU storage and disposition, include program requirements, roles and responsibilities, program activities (action plans), milestone schedules, and deliverables

Assessment of the U.S. regulations for fissile exemptions and fissile material general licenses

International Nuclear Information System (INIS)

Parks, C.V.; Hopper, C.M.; Lichtenwalter, J.J.; Easton, E.P.; Brochman, P.G.

1998-05-01

The paragraphs for general licenses for fissile material and exemptions (often termed exceptions in the international community) for fissile material have long been a part of the US Code of Federal Regulations (CFR) 10 CFR Part 71, Packaging and Transportation of Radioactive Material. More recently, the Nuclear Regulatory Commission (NRC) issued a final rule on Part 71 via emergency rule-making procedures in order to address an identified deficiency related to one of the fissile exemptions. To address the specified deficiency in a general fashion, the emergency rule adopted the approach of the 1996 Edition of the IAEA: Regulations for the Safe Transport of Radioactive Material (IAEA 1996), which places restrictions on certain moderating materials and limits the quantity of fissile material in a consignment. The public comments received by the NRC indicated general agreement with the need for restrictions on certain moderators (beryllium, deuterium, and graphite). The comments indicated concern relative to both the degree of restriction imposed (not more than 0.1% of fissile material mass) and the need to limit the fissile material mass of the consignment, particularly in light of the subsequent NRC staff position that the true intent was to provide control for limiting the fissile mass of the conveyance. The purpose of the review is to identify potential deficiencies that might be adverse to maintaining adequate subcriticality under normal conditions of transport and hypothetical accident conditions. In addition, ORNL has been asked to identify changes that would address any identified safety issues, enable inherently safe packages to continue to be unencumbered in transport, and seek to minimize the impact on current safe practices

Recovery of fissile materials from plutonium residues, miscellaneous spent nuclear fuel, and uranium fissile wastes

International Nuclear Information System (INIS)

Forsberg, C.W.

1997-01-01

A new process is proposed that converts complex feeds containing fissile materials into a chemical form that allows the use of existing technologies (such as PUREX and ion exchange) to recover the fissile materials and convert the resultant wastes to glass. Potential feed materials include (1) plutonium scrap and residue, (2) miscellaneous spent nuclear fuel, and (3) uranium fissile wastes. The initial feed materials may contain mixtures of metals, ceramics, amorphous solids, halides, and organics. 14 refs., 4 figs

History of the US weapons-usable plutonium disposition program leading to DOE's record of decision

International Nuclear Information System (INIS)

Spellman, D.J.; Thomas, J.F.; Bugos, R.G.

1997-04-01

This report highlights important events and studies concerning surplus weapons-usable plutonium disposition in the United States. Included are major events that led to the creation of the U.S. Department of Energy (DOE) Office of Fissile Materials Disposition in 1994 and to that DOE office issuing the January 1997 Record of Decision for the Storage and Disposition of Weapons-Useable Fissile Materials Final Programmatic Environmental Impact Statement. Emphasis has been given to reactor-based plutonium disposition alternatives

Direct conversion of surplus fissile materials, spent nuclear fuel, and other materials to high-level-waste glass

International Nuclear Information System (INIS)

Forsberg, C.W.; Elam, K.R.

1995-01-01

With the end of the cold war the United States, Russia, and other countries have excess plutonium and other materials from the reductions in inventories of nuclear weapons. The United States Academy of Sciences (NAS) has recommended that these surplus fissile materials (SFMs) be processed so they are no more accessible than plutonium in spent nuclear fuel (SNF). This spent fuel standard, if adopted worldwide, would prevent rapid recovery of SFMs for the manufacture of nuclear weapons. The NAS recommended investigation of three sets of options for disposition of SFMs while meeting the spent fuel standard: (1) incorporate SFMs with highly radioactive materials and dispose of as waste, (2) partly burn the SFMs in reactors with conversion of the SFMs to SNF for disposal, and (3) dispose of the SFMs in deep boreholes. The US Government is investigating these options for SFM disposition. A new method for the disposition of SFMs is described herein: the simultaneous conversion of SFMs, SNF, and other highly radioactive materials into high-level-waste (HLW) glass. The SFMs include plutonium, neptinium, americium, and 233 U. The primary SFM is plutonium. The preferred SNF is degraded SNF, which may require processing before it can be accepted by a geological repository for disposal

Far-Field Accumulation of Fissile Material From Waste Packages Containing Plutonium Disposition Waste Form

International Nuclear Information System (INIS)

J.P. Nicot

2000-01-01

The objective of this calculation is to estimate the quantity of fissile material that could accumulate in fractures in the rock beneath plutonium-ceramic (Pu-ceramic) and Mixed-Oxide (MOX) waste packages (WPs) as they degrade in the potential monitored geologic repository at Yucca Mountain. This calculation is to feed another calculation (Ref. 31) computing the probability of criticality in the systems described in Section 6 and then ultimately to a more general report on the impact of plutonium on the performance of the proposed repository (Ref. 32), both developed concurrently to this work. This calculation is done in accordance with the development plan TDP-DDC-MD-000001 (Ref. 9), item 5. The original document described in item 5 has been split into two documents: this calculation and Ref. 4. The scope of the calculation is limited to only very low flow rates because they lead to the most conservative cases for Pu accumulation and more generally are consistent with the way the effluent from the WP (called source term in this calculation) was calculated (Ref. 4). Ref. 4 (''In-Drift Accumulation of Fissile Material from WPs Containing Plutonium Disposition Waste Forms'') details the evolution through time (breach time is initial time) of the chemical composition of the solution inside the WP as degradation of the fuel and other materials proceed. It is the chemical solution used as a source term in this calculation. Ref. 4 takes that same source term and reacts it with the invert; this calculation reacts it with the rock. In addition to reactions with the rock minerals (that release Si and Ca), the basic mechanisms for actinide precipitation are dilution and mixing with resident water as explained in Section 2.1.4. No other potential mechanism such as flow through a reducing zone is investigated in this calculation. No attempt was made to use the effluent water from the bottom of the invert instead of using directly the effluent water from the WP. This

Far-Field Accumulation of Fissile Material From Waste Packages Containing Plutonium Disposition Waste Form

Energy Technology Data Exchange (ETDEWEB)

J.P. Nicot

2000-09-29

The objective of this calculation is to estimate the quantity of fissile material that could accumulate in fractures in the rock beneath plutonium-ceramic (Pu-ceramic) and Mixed-Oxide (MOX) waste packages (WPs) as they degrade in the potential monitored geologic repository at Yucca Mountain. This calculation is to feed another calculation (Ref. 31) computing the probability of criticality in the systems described in Section 6 and then ultimately to a more general report on the impact of plutonium on the performance of the proposed repository (Ref. 32), both developed concurrently to this work. This calculation is done in accordance with the development plan TDP-DDC-MD-000001 (Ref. 9), item 5. The original document described in item 5 has been split into two documents: this calculation and Ref. 4. The scope of the calculation is limited to only very low flow rates because they lead to the most conservative cases for Pu accumulation and more generally are consistent with the way the effluent from the WP (called source term in this calculation) was calculated (Ref. 4). Ref. 4 (''In-Drift Accumulation of Fissile Material from WPs Containing Plutonium Disposition Waste Forms'') details the evolution through time (breach time is initial time) of the chemical composition of the solution inside the WP as degradation of the fuel and other materials proceed. It is the chemical solution used as a source term in this calculation. Ref. 4 takes that same source term and reacts it with the invert; this calculation reacts it with the rock. In addition to reactions with the rock minerals (that release Si and Ca), the basic mechanisms for actinide precipitation are dilution and mixing with resident water as explained in Section 2.1.4. No other potential mechanism such as flow through a reducing zone is investigated in this calculation. No attempt was made to use the effluent water from the bottom of the invert instead of using directly the effluent water from the

A methodology for the analysis and selection of alternatives for the disposition of surplus plutonium. Quarterly technical progress report, April 1, 1995--June 30, 1995

International Nuclear Information System (INIS)

Mulder, R.

1995-01-01

The Office of Fissile Materials Disposition is currently involved in the development of a comprehensive approach to the long-term storage and disposition of fissile materials. A major objective of this effort is to provide a framework for US efforts to prevent the proliferation of nuclear weapons. This will entail both the elimination of excess highly enriched uranium and plutonium, and the insurance of the highest standards of safety, security, and international accountability. The Office of Fissile Materials Disposition is supporting an Interagency Working Group that has initiated a comprehensive review of alternatives for plutonium disposition which takes into account non-proliferation, economic, technical, institutional, schedule, environmental, and health and safety issues. These alternatives were identified by the development of screening criteria as a guide to the selection of alternatives that best achieve the fissile nuclear material long-term storage and disposition goals of the US Government

Enhanced safety in the storage of fissile materials

International Nuclear Information System (INIS)

Williams, G.E.; Alvares, N.J.

1979-01-01

A ''plastic-like'' supporting material impregnated with a neutron-absorbing agent that is suitable for ''lining'' the inner surfaces of fissile-material storage containers was fabricated. The material consists, by weight, of 50% food-grade borax, 25% coal tar, and 25% epoxy resin. It costs much less than commercially available materials, can absorb enough neutrons to isolate units of fissile material, and possesses such structural qualities as flexibility and machinability. Properties and performance of the material are discussed

Enhanced safety in the storage of fissile materials

International Nuclear Information System (INIS)

Williams, G.E.; Alvares, N.J.

1978-01-01

An inexpensive boron-loaded liner of epoxy resin for fissile-material storage containers was developed that can be easily fabricated of readily available, low-cost materials. Computer calculations indicate reactivity will be reduced substantially if this neutron-absorbing liner is added to containers in a typical storage array. These calculations compare favorably with neutron-attenuation experiments with thermal and fission neutron spectra, and tests at the Fire Test Facility indicate the epoxy resin will survive extreme environmental and accident conditions. The fire-resistant and insulating properties of the epoxy-resin liner further augment its ability to protect fissile materials. Boron-loaded epoxy resin is adaptable to many tasks but is particularly useful for providing enhanced criticality safety in the packaging and storage of fissile materials

In-Drift Accumulation of Fissile Material From Waste Packages Containing Plutonium Disposition Waste Forms

International Nuclear Information System (INIS)

H.W. Stockman; S. LeStrange

2000-01-01

The objective of this calculation is to provide estimates of the amount of fissile material flowing out of the waste package (source term) and the accumulation of fissile elements (U and Pu) in a crushed-tuff invert. These calculations provide input for the analysis of repository impacts of the Pu-ceramic waste forms. In particular, the source term results are used as input to the far-field accumulation calculation reported in Ref. 51, and the in-drift accumulation results are used as inputs for the criticality calculations reported in Ref. 2. The results are also summarized and interpreted in Ref. 52. The scope of this calculation is the waste package (WP) Viability Assessment (VA) design, which consists of an outer corrosion-allowance material (CAM) and an inner corrosion-resistant material (CRM). This design is used in this calculation in order to be consistent with earlier Pu-ceramic degradation calculations (Ref. 15). The impact of the new Enhanced Design Alternative-I1 (EDA-11) design on the results will be addressed in a subsequent report. The design of the invert (a leveling foundation, which creates a level surface of the drift floor and supports the WP mounting structure) is consistent with the EDA-I1 design. The invert will be composed of crushed stone and a steel support structure (Ref. 17). The scope of this calculation is also defined by the nominal degradation scenario, which involves the breach of the WP (Section 10.5.1.2, Ref. 48), followed by the influx of water. Water in the WP may, in time, gradually leach the fissile components and neutron absorbers out of the ceramic waste forms. Thus, the water in the WP may become laden with dissolved actinides (e.g., Pu and U), and may eventually overflow or leak from the WP. Once the water leaves the WP, it may encounter the invert, in which the actinides may reprecipitate. Several factors could induce reprecipitation; these factors include: the high surface area of the crushed stone, and the presence of

In-Drift Accumulation of Fissile Material From Waste Packages Containing Plutonium Disposition Waste Form

Energy Technology Data Exchange (ETDEWEB)

H.W> Stockman; S. LeStrange

2000-09-28

The objective of this calculation is to provide estimates of the amount of fissile material flowing out of the waste package (source term) and the accumulation of fissile elements (U and Pu) in a crushed-tuff invert. These calculations provide input for the analysis of repository impacts of the Pu-ceramic waste forms. In particular, the source term results are used as input to the far-field accumulation calculation reported in Ref. 51, and the in-drift accumulation results are used as inputs for the criticality calculations reported in Ref. 2. The results are also summarized and interpreted in Ref. 52. The scope of this calculation is the waste package (WP) Viability Assessment (VA) design, which consists of an outer corrosion-allowance material (CAM) and an inner corrosion-resistant material (CRM). This design is used in this calculation in order to be consistent with earlier Pu-ceramic degradation calculations (Ref. 15). The impact of the new Enhanced Design Alternative-I1 (EDA-11) design on the results will be addressed in a subsequent report. The design of the invert (a leveling foundation, which creates a level surface of the drift floor and supports the WP mounting structure) is consistent with the EDA-I1 design. The invert will be composed of crushed stone and a steel support structure (Ref. 17). The scope of this calculation is also defined by the nominal degradation scenario, which involves the breach of the WP (Section 10.5.1.2, Ref. 48), followed by the influx of water. Water in the WP may, in time, gradually leach the fissile components and neutron absorbers out of the ceramic waste forms. Thus, the water in the WP may become laden with dissolved actinides (e.g., Pu and U), and may eventually overflow or leak from the WP. Once the water leaves the WP, it may encounter the invert, in which the actinides may reprecipitate. Several factors could induce reprecipitation; these factors include: the high surface area of the crushed stone, and the presence of

Canyon transfer neutron absorber to fissile material ratio analysis. Revision 1

International Nuclear Information System (INIS)

Clemmons, J.S.

1994-01-01

Waste tank fissile material and non-fissile material estimates are used to evaluate criticality safety for the existing sludge inventory and batches of sludge sent to Extended Sludge Processing (ESP). This report documents the weight ratios of several non-fissile waste constituents to fissile waste constituents from canyon reprocessing waste streams. Weight ratios of Fe, Mn, Al, Mi, and U-238 to fissile material are calculated from monthly loss estimates from the F and H Canyon Low Heat Waste (LHW) and High Heat Waste (HHW) streams. The monthly weight ratios for Fe, Mn and U-238 are then compared to calculated minimum safe weight ratios. Documented minimum safe weight ratios for Al and Ni to fissile material are currently not available. Total mass data for the subject sludge constituents is provided along with scatter plots of the monthly weight ratios for each waste stream

Electronuclear conversion of fertile to fissile material

International Nuclear Information System (INIS)

Van Atta, C.M.; Lee, J.D.; Heckrotte, W.

1976-01-01

The electronuclear conversion of fertile to fissile material by accelerator-produced neutrons is discussed. Experimental and theoretical results obtained in the MTA program (1949--1954) on the production of low-energy (less than 20-MeV) neutrons by high-energy proton, deuteron, and neutron bombardment of target materials are briefly reviewed. More recent calculations of the cascade process, by which the low-energy neutrons are produced, are discussed. A system is described by which 500- to 600-MeV deuterons incident on a lithium primary target can be converted to high-energy neutrons, which can be multiplied by spallation cascades and nuclear excitation to produce low-energy neutrons in a depleted-uranium or thorium secondary target. Fission events producing heat and additional neutrons are produced. The evaporation and fission neutrons would be captured, and fissile material would be produced. The production rates for 239 Pu and 233 U are estimated for 0.25-A and 0.375-A deuteron beams from an Alvarez linac. The capital and operating costs are estimated, and the resulting costs of fissile materials are calculated. The cost of generating power in reactors using the fissile material so produced as make-up fuel is also estimated. The energy multiplication (power generated in reactors so fueled/power consumed by the accelerator) ranges from about 10 to about 50 depending upon the make-up of the secondary target; depleted uranium, thorium, or a combination of the two. An experimental and theoretical program to facilitate optimization of the parameters of a production installation is described. 13 figures, 14 tables

X-ray fluorescence spectroscopy for the elemental analysis of plutonium-bearing materials for the materials disposition program

International Nuclear Information System (INIS)

Voit, S.L.; Boerigter, S.T.; Rising, T.L.

1997-01-01

The US Fissile Materials Disposition (MD) program will disposition about 50 MT of plutonium in the next century. Both of the alternative technologies for disposition, MOX Fuel and Immobilization require knowledge of the incoming composition to 1--5 wt%. Wavelength Dispersive X-Ray Fluorescence (WDXRF) systems, a common elemental analysis technology with a variety of industrial applications and commercial vendors, can readily achieve this level of characterization. Since much of the excess plutonium will be packaged in a long-term storage container as part of the DOE Environmental Management (DOE-EM) program to stabilize plutonium-bearing materials, the characterization system must be implemented during the packaging process. The authors describe a preliminary design for the integration of the WDXRF system into the packaging system to be used at the Rocky Flats site. The Plutonium Stabilization and Packaging System (PuSPS), coupled with the WDXRF characterization system will provide MD with stabilized plutonium-bearing excess material that can be more readily fed to an immobilization facility. The overall added expense to the MD program of obtaining analytical information after materials have been packaged in long-term storage containers could far exceed the expense of implementing XRF analysis during the packaging process

Accelerating fissile material detection with a neutron source

Science.gov (United States)

Rowland, Mark S.; Snyderman, Neal J.

2018-01-30

A neutron detector system for discriminating fissile material from non-fissile material wherein a digital data acquisition unit collects data at high rate, and in real-time processes large volumes of data directly to count neutrons from the unknown source and detecting excess grouped neutrons to identify fission in the unknown source. The system includes a Poisson neutron generator for in-beam interrogation of a possible fissile neutron source and a DC power supply that exhibits electrical ripple on the order of less than one part per million. Certain voltage multiplier circuits, such as Cockroft-Walton voltage multipliers, are used to enhance the effective of series resistor-inductor circuits components to reduce the ripple associated with traditional AC rectified, high voltage DC power supplies.

Warhead and fissile-material declarations

International Nuclear Information System (INIS)

von Hippel, F.

1992-01-01

Until recently, arms control agreements were limited by the fact that the only available verification capabilities were national technical means, which involved instruments in space or beyond national borders. As a result, the SALT II treaty constrained only the construction of large missile silos, ballistic-missile submarines and long-range bombers - and limited the flight testing of long-range ballistic missiles. Recently, however, on-site verification has been accepted, making it possible in the INF treaty to extend controls to small mobile missiles and their launchers. This paper therefore outlines a comprehensive system of verifiable limits on nuclear warheads. The authors discuss in some detail the verifiability of a halt in the production of fissile materials for nuclear warheads, the verifiability of declarations of the amounts of fissile material produced for warheads prior to the production cutoff, and the establishment of a verifiable accounting system for the numbers and types of nuclear warheads possessed by each side

Fissile material ban: global and non-discriminatory?

International Nuclear Information System (INIS)

Datt, Savita

1995-01-01

With the indefinite and unconditional extension of the nuclear Non-Proliferation Treaty (NPT) now out of the way, the next issue on the non-proliferation agenda is that of the existing stocks and further production of plutonium and weapons grade uranium. More than the existing stocks and the surplus fissile materials made available through arms control and disarmament measures, it is the further production of such materials which is sought to be tackled urgently. Of prime concern are the nuclear programmes of threshold countries like India, Pakistan and Israel (countries out of the NPT fold) which need to be capped at all costs. The best method of achieving this, it is believed can be through a global ban on the production of fissile materials. 15 refs

Criticality Control Fissile of Materials. Proceedings of the Symposium on Criticality Control of Fissile Materials

Energy Technology Data Exchange (ETDEWEB)

NONE

1966-05-15

Criticality control comprises all the administrative and technical procedures which enable the storage and processing of fissile material to be carried out under conditions of nuclear safety. It is of particular importance in the safe design and operation of chemical and metallurgical plants processing fissile material, in the handling and storage of enriched fuel for reactors, and in transportation of fissile material. The growth of nuclear power, with its increasing use of fissile material and production of plutonium, is leading to an ever widening need for this discipline. This Symposium was held 4 Vulgar-Fraction-One-Half years after the only other international meeting on this topic, at which the first broad exchange of ideas and theories enabled a comparison to be drawn between the various ways in which the subject is handled in the different countries. That meeting showed that criticality safety was often achieved by procedures known to be ultra-safe, as there was a great lack of useful experimental data with which to check theoretical models. Since that time the quantities of material being processed have increased, and with the now urgent necessity of achieving economic, and hence commercially competitive, operation, the procedure of using arbitrary factors of safety is no longer adequate. Plant Managers now require good data on the basis of which they can choose a suitable factor of safety, and design a process to be safe under any foreseeable circumstances. The present Symposium showed the great increase in the amount of available experimental data and its importance in checking the now highly sophisticated computer calculations. There are many diagrams in these Proceedings with curves from which critical parameters for various configurations can be taken. The dearth of data for plutonium systems is causing some difficulty in plutonium processing plants, which are becoming commercially important. The excellent safety record of the atomic energy industry

Verification arrangements for the proposed fissile material cut-off treaty

International Nuclear Information System (INIS)

Bragin, V.

2001-01-01

Since the mid-1950's, an agreement to terminate the production of fissile material for nuclear weapons has been on the agenda. On December 16, 1993, the UNGA adopted Resolution A/RES/48/75/L which recommends ''the negotiation in the most appropriate international forum of a non-discriminatory, multilateral and internationally and effectively verifiable treaty banning the production of fissile material for nuclear weapons and other nuclear explosive devices''. The proposed Fissile Material Cut-off Treaty (FMCT) is still one of the most important items on the multilateral disarmament and non-proliferation agenda. Successful achievement of the FMCT would be an important step towards the goal of eliminating nuclear weapons. (author)

Recovery of fissile materials from nuclear wastes

Science.gov (United States)

Forsberg, Charles W.

1999-01-01

A process for recovering fissile materials such as uranium, and plutonium, and rare earth elements, from complex waste feed material, and converting the remaining wastes into a waste glass suitable for storage or disposal. The waste feed is mixed with a dissolution glass formed of lead oxide and boron oxide resulting in oxidation, dehalogenation, and dissolution of metal oxides. Carbon is added to remove lead oxide, and a boron oxide fusion melt is produced. The fusion melt is essentially devoid of organic materials and halogens, and is easily and rapidly dissolved in nitric acid. After dissolution, uranium, plutonium and rare earth elements are separated from the acid and recovered by processes such as PUREX or ion exchange. The remaining acid waste stream is vitrified to produce a waste glass suitable for storage or disposal. Potential waste feed materials include plutonium scrap and residue, miscellaneous spent nuclear fuel, and uranium fissile wastes. The initial feed materials may contain mixtures of metals, ceramics, amorphous solids, halides, organic material and other carbon-containing material.

Transportation of fissile materials and the danger of criticity

International Nuclear Information System (INIS)

Haon, D.; Leclerc, J.; Maubert, L.

1981-01-01

The authors examine the risk of criticity that can arise during the transportation of fissile matter. They then outline the regulations and studies made in the field of criticity-safety and the computation methods used. They discuss the applications that are reflected in the concept and design of fissile material packagings [fr

Immobilization as a route to surplus fissile materials disposition. Revision 1

International Nuclear Information System (INIS)

Gray, L.W.; Kan, T.; McKibben, J.M.

1996-01-01

The safe management of surplus weapons plutonium is a very important and urgent task with profound environmental, national and international security implications. In the aftermath of the Cold War, Presidential Police Directive 13 and various analysis by renown scientific, technical and international policy organizations have brought about a focused effort within the Department of Energy to identify and implement paths forward for the long term disposition of surplus weapons usable plutonium. The central, overarching goal is to render surplus weapons plutonium as inaccessible and unattractive for reuse in nuclear weapons, as the much larger and growing stock of plutonium contained in civilian spent reactor fuel. One disposition alternative considered for surplus Pu is immobilization, in which plutonium would be emplaced in glass, ceramic or glass-bonded zeolite. This option, along with some of the progress over the last year is discussed

Fuel costs of a light water reactor with fissile material recycling

International Nuclear Information System (INIS)

Clauss, J.

1984-01-01

In the light of the present prices of natural uranium and separative work and fabrication costs, savings can be achieved by reloading recycled fissile material. As in all recycling techniques, the product recovered cannot meet the whole new requirement. No excessive economic expectations should be associated with fissile material recycling in ligth water reactors. The main advantages of the procedure are the conservation of resources and the safety against proliferation. Besides, the original purpose of reprocessing should not be forgotten, i.e., in addition to the recycling of fissile material, to have a safe and easy method of secular disposal of high level waste (concentrated fission products). (orig.) [de

A line of defense approach to fissile material control

International Nuclear Information System (INIS)

Holloway, S.P.; Holloway, N.J.

1995-01-01

A crucial element of the safety policy of the UK Atomic Weapons Establishment (AWE) is that concerned with the safe control of fissile material in order to minimize the potential for unplanned criticality. The principles by which AWE controls fissile material advocate a simple Line of Defense (LOD) approach to assessing criticality-safety related aspects of fissile operations. An LOD assessment provides a measure of the depth of defense available to prevent general types of criticality accident and can be used to demonstrate compliance with the risk-based Basic Safety Limits (BSLs) and Objectives (BSOs) used by the UK Nuclear Installations Inspectorate (NII) to judge the safety of operations in accordance with its Safety Assessment Principles (SAPs) for Nuclear Plants. This paper discusses the LOD concept, the basis of LOD assessment and describes LODs specific to criticality control

Fissile material proliferation risk

International Nuclear Information System (INIS)

Dreicer, J.S.; Rutherford, D.A.

1996-01-01

The proliferation risk of a facility depends on the material attractiveness, level of safeguards, and physical protection applied to the material in conjunction with an assessment of the impact of the socioeconomic circumstances and threat environment. Proliferation risk is a complementary extension of proliferation resistance. The authors believe a better determination of nuclear proliferation can be achieved by establishing the proliferation risk for facilities that contain nuclear material. Developing a method that incorporates the socioeconomic circumstances and threat environment inherent to each country enables a global proliferation assessment. To effectively reduce the nuclear danger, a broadly based set of criteria is needed that provides the capability to relatively assess a wide range of nuclear related sites and facilities in different countries and still ensure a global decrease in proliferation risk for fissile material (plutonium and highly enriched uranium)

Fissile materials detection

International Nuclear Information System (INIS)

Dumesnil, P.

1977-03-01

Description is given of three types of apparatus intended for controlling fossile materials in view of avoiding their diversion or preventing said products to be mixed to less dangerous radioactive wastes. The gantry-type apparatus is intended for the detection of small masses of fissile materials moving through a crossing place; the neutron gantry consists of helium 3 detectors of the type 150NH100, located inside polyethylene blocks; as for the gamma gantry, it consists of two large plastic scintillators integrated to the vertical legs of said gantry. The second apparatus is a high-efficiency detector intended for controlling Pu inside waste casks. It can detect 10mg of Pu inside a 100 liters drum for one minute counting. The third apparatus intended for persons and things monitoring is still on study. Such as the gantries it is based on sampled measurement of the background noise [fr

The back-end management of fissile material at SCK-CEN

International Nuclear Information System (INIS)

Noynaert, L.; Massaut, V.; Braeckeveldt, M.

1999-01-01

The back-end management of fissile materials at SCK-CEN mainly concerns the HEU spent fuel of the BR2 (MTR) and the LEU and MOX spent fuel of the BR3, the first PWR installed in Western Europe and in decommissioning since 1987. It also concerns the experimental fuels tested in the SCK-CEN facilities. Furthermore as a result of its R and D programs in reprocessing and characterisation of spent fuel, considerable amounts of fissile materials in all kinds of forms and characteristics are stored in the different laboratories. For these, six main types of fissile materials are identified: highly enriched uranium, experimental spent fuel from the fast breeder programmes, MOX fuel, low enriched fuel, natural uranium and lab fissile materials. For the BR2 and BR3 spent fuel, various options, i.e. reprocessing, dry storage in casks and dry storage in canisters were evaluated against criteria, e.g. available techniques, safety, waste production, overall costs and policies. As a result of these studies, it was decided to opt in the case of the HEU from the BR2 reactor for the reprocessing without recovery of uranium while for the LEU and MOX fuel from the BR3 reactor, the dry storage in containers was chosen. For the others, the studies are still in progress. (author)

Global nuclear material control model

International Nuclear Information System (INIS)

Dreicer, J.S.; Rutherford, D.A.

1996-01-01

The nuclear danger can be reduced by a system for global management, protection, control, and accounting as part of a disposition program for special nuclear materials. The development of an international fissile material management and control regime requires conceptual research supported by an analytical and modeling tool that treats the nuclear fuel cycle as a complete system. Such a tool must represent the fundamental data, information, and capabilities of the fuel cycle including an assessment of the global distribution of military and civilian fissile material inventories, a representation of the proliferation pertinent physical processes, and a framework supportive of national or international perspective. They have developed a prototype global nuclear material management and control systems analysis capability, the Global Nuclear Material Control (GNMC) model. The GNMC model establishes the framework for evaluating the global production, disposition, and safeguards and security requirements for fissile nuclear material

Nuclear energy - Fissile materials - Principles of criticality safety in storing, handling and processing

International Nuclear Information System (INIS)

1995-01-01

This International Standard specifies the basic principles and limitations which govern operations with fissile materials. It discusses general criticality safety criteria for equipment design and for the development of operating controls, while providing guidance for the assessment of procedures, equipment, and operations. It does not cover quality assurance requirements or details of equipment or operational procedures, nor does it cover the effects of radiation on man or materials, or sources of such radiation, either natural or as the result of nuclear chain reactions. Transport of fissile materials outside the boundaries of nuclear establishments is not within the scope of this International Standard and should be governed by appropriate national and international standards and regulations. These criteria apply to operations with fissile materials outside nuclear reactors but within the boundaries of nuclear establishments. They are concerned with the limitations which must be imposed on operations because of the unique properties of these materials which permit them to support nuclear chain reactions. These principles apply to quantities of fissile materials in which nuclear criticality can be established

Requirements for timber and cadmium used in shielding for fissile material transport packaging

International Nuclear Information System (INIS)

1982-02-01

This Code of Practice has been prepared as a guide for designers who require packaging for fissile materials. It should be noted that this document covers design requirements only and it is not a manufacturing specification which can be quoted on a manufacturing contract without qualification. Compliance with the regulations regarding the safe transport of fissile materials may be achieved by the provision of an effective shield embodying:- (a) a moderating material -usually one rich in hydrogen, such as wood - in order to thermalise incoming neutrons, and (b) a material - such as cadmium - with a large absorption cross-section for thermal neutrons, located between the moderator and the fissile material, in order to capture the incoming neutrons. This Code describes the requirements in two sections, one for each of these materials. (author)

Revisited. Euratom's ownership of special fissile materials

International Nuclear Information System (INIS)

Pelzer, Norbert

2015-01-01

Among all Treaties on the Foundation of the European Community, seemingly, the Euratom Treaty ist the most unobtrusive one having even nearly been declared dead occasionally. For the opponents of nuclear energy the treaty is a thorn in their side because it aims for the peaceful exploitation of nuclear energy. Actually, the treaty likewise aims for the protection of dangers of nuclear energy and encloses a bundle of collective control instruments. The protective purpose provides the community with a strong position in numerous fields towards nuclear energy users including the right to intervene in the operations of nuclear facilities. The communitie's position is further strengthened by the communitie's ownership on special fissile materials. The EAEC Treaty determines: 'Special fissile materials are owned by the community'. The material content of Euratom's ownership is limited by Article 87 of the EAEC Treaty: Unlimited right of use and consumption is granted to the properly possessors unless obligations of the Euratom Treaty oppose. Inherently, the community does not have these rights. It was asked what would be left to the owner Euratom if the properly possessor is entitled to unlimited right of use and even right of consumption.

ANL-W MOX fuel lead assemblies data report for the surplus plutonium disposition environmental impact statement

International Nuclear Information System (INIS)

O'Connor, D.G.; Fisher, S.E.; Holdaway, R.

1997-08-01

The purpose of this document is to support the US Department of Energy (DOE) Fissile Materials Disposition Program's preparation of the draft surplus plutonium disposition environmental impact statement (EIS). This is one of several responses to data call requests for background information on activities associated with the operation of the lead assembly (LA) mixed-oxide (MOX) fuel fabrication facility. The DOE Office of fissile Materials Disposition (DOE-MD) has developed a dual-path strategy for disposition of surplus weapons-grade plutonium. One of the paths is to disposition surplus plutonium through irradiation of MOX fuel in commercial nuclear reactors. MOX fuel consists of plutonium and uranium oxides (PuO 2 and UO 2 ), typically containing 95% or more UO 2 . DOE-MD requested that the DOE Site Operations Offices nominate DOE sites that meet established minimum requirements that could produce MOX LAs. The paper describes the following: Site map and the LA facility; process descriptions; resource needs; employment requirements; wastes, emissions, and exposures; accident analysis; transportation; qualitative decontamination and decommissioning; post-irradiation examination; LA fuel bundle fabrication; LA EIS data report assumptions; and LA EIS data report supplement

ANL-W MOX fuel lead assemblies data report for the surplus plutonium disposition environmental impact statement

Energy Technology Data Exchange (ETDEWEB)

O`Connor, D.G.; Fisher, S.E.; Holdaway, R. [and others

1997-08-01

The purpose of this document is to support the US Department of Energy (DOE) Fissile Materials Disposition Program`s preparation of the draft surplus plutonium disposition environmental impact statement (EIS). This is one of several responses to data call requests for background information on activities associated with the operation of the lead assembly (LA) mixed-oxide (MOX) fuel fabrication facility. The DOE Office of fissile Materials Disposition (DOE-MD) has developed a dual-path strategy for disposition of surplus weapons-grade plutonium. One of the paths is to disposition surplus plutonium through irradiation of MOX fuel in commercial nuclear reactors. MOX fuel consists of plutonium and uranium oxides (PuO{sub 2} and UO{sub 2}), typically containing 95% or more UO{sub 2}. DOE-MD requested that the DOE Site Operations Offices nominate DOE sites that meet established minimum requirements that could produce MOX LAs. The paper describes the following: Site map and the LA facility; process descriptions; resource needs; employment requirements; wastes, emissions, and exposures; accident analysis; transportation; qualitative decontamination and decommissioning; post-irradiation examination; LA fuel bundle fabrication; LA EIS data report assumptions; and LA EIS data report supplement.

Mathematical model for choosing the nuclear safe matrix compositions for fissile material immobilization

International Nuclear Information System (INIS)

Gorshtein, A.I.; Matyunin, Yu.I.; Poluehktov, P.P.

2000-01-01

A mathematical model is proposed for preliminary choice of the nuclear safe matrix compositions for fissile material immobilization. The IBM PC computer software for nuclear safe matrix composition calculations is developed. The limiting concentration of fissile materials in the some used and perspective nuclear safe matrix compositions for radioactive waste immobilization is calculated [ru

Modeling of fissile material diversion in solvent extraction cascades

International Nuclear Information System (INIS)

Schneider, A.; Carlson, R.W.

1980-01-01

Changes were calculated for measurable parameters of a solvent extraction section of a reprocessing plant resulting from postulated fissile material diversion actions. The computer program SEPHIS was modified to calculate the time-dependent concentrations of uranium and plutonium in each stage of a cascade. The calculation of the inventories of uranium and plutonium in each contactor was also included. The concentration and inventory histories were computed for a group of four sequential columns during start-up and for postulated diversion conditions within this group of columns. Monitoring of column exit streams or of integrated column inventories for fissile materials could provide qualitative indications of attempted diversions. However, the time delays and resulting changes are complex and do not correlate quantitatively with the magnitude of the initiating event

1980 Annual status report: fissile materials control and management

International Nuclear Information System (INIS)

1981-01-01

The R and D activities of the JRC in the field of Fissile Material Control and Management are oriented to the development of safeguards systems in the European Community nuclear fuel cycle and to provide means for a more efficient nuclear material management within the nuclear industry

Fissile material detection and control facility with pulsed neutron sources and digital data processing

International Nuclear Information System (INIS)

Romodanov, V.L.; Chernikova, D.N.; Afanasiev, V.V.

2010-01-01

Full text: In connection with possible nuclear terrorism, there is long-felt need of devices for effective control of radioactive and fissile materials in the key points of crossing the state borders (airports, seaports, etc.), as well as various customs check-points. In International Science and Technology Center Projects No. 596 and No. 2978, a new physical method and digital technology have been developed for the detection of fissile and radioactive materials in models of customs facilities with a graphite moderator, pulsed neutron source and digital processing of responses from scintillation PSD detectors. Detectability of fissile materials, even those shielded with various radiation-absorbing screens, has been shown. The use of digital processing of scintillation signals in this facility is a necessary element, as neutrons and photons are discriminated in the time dependence of fissile materials responses at such loads on the electronic channels that standard types of spectrometers are inapplicable. Digital processing of neutron and photon responses practically resolves the problem of dead time and allows implementing devices, in which various energy groups of neutrons exist for some time after a pulse of source neutrons. Thus, it is possible to detect fissile materials deliberately concealed with shields having a large cross-section of absorption of photons and thermal neutrons. Two models of detection and the control of fissile materials were advanced: 1. the model based on graphite neutrons moderator and PSD scintillators with digital technology of neutrons and photons responses separation; 2. the model based on plastic scintillators and detecting of time coincidences of fission particles by digital technology. Facilities that count time coincidences of neutrons and photons occurring in the fission of fissile materials can use an Am Li source of neutrons, e.g. that is the case with the AWCC system. The disadvantages of the facility are related to the issues

Detection of tiny amounts of fissile materials in large-sized containers with radioactive waste

Science.gov (United States)

Batyaev, V. F.; Skliarov, S. V.

2018-01-01

The paper is devoted to non-destructive control of tiny amounts of fissile materials in large-sized containers filled with radioactive waste (RAW). The aim of this work is to model an active neutron interrogation facility for detection of fissile ma-terials inside NZK type containers with RAW and determine the minimal detectable mass of U-235 as a function of various param-eters: matrix type, nonuniformity of container filling, neutron gen-erator parameters (flux, pulse frequency, pulse duration), meas-urement time. As a result the dependence of minimal detectable mass on fissile materials location inside container is shown. Nonu-niformity of the thermal neutron flux inside a container is the main reason of the space-heterogeneity of minimal detectable mass in-side a large-sized container. Our experiments with tiny amounts of uranium-235 (<1 g) confirm the detection of fissile materials in NZK containers by using active neutron interrogation technique.

Detection of tiny amounts of fissile materials in large-sized containers with radioactive waste

Directory of Open Access Journals (Sweden)

Batyaev V.F.

2018-01-01

Full Text Available The paper is devoted to non-destructive control of tiny amounts of fissile materials in large-sized containers filled with radioactive waste (RAW. The aim of this work is to model an active neutron interrogation facility for detection of fissile ma-terials inside NZK type containers with RAW and determine the minimal detectable mass of U-235 as a function of various param-eters: matrix type, nonuniformity of container filling, neutron gen-erator parameters (flux, pulse frequency, pulse duration, meas-urement time. As a result the dependence of minimal detectable mass on fissile materials location inside container is shown. Nonu-niformity of the thermal neutron flux inside a container is the main reason of the space-heterogeneity of minimal detectable mass in-side a large-sized container. Our experiments with tiny amounts of uranium-235 (<1 g confirm the detection of fissile materials in NZK containers by using active neutron interrogation technique.

Recommended nuclear criticality safety experiments in support of the safe transportation of fissile material

International Nuclear Information System (INIS)

Tollefson, D.A.; Elliott, E.P.; Dyer, H.R.; Thompson, S.A.

1993-01-01

Validation of computer codes and nuclear data (cross-section) libraries using benchmark quality critical (or certain subcritical) experiments is an essential part of a nuclear criticality safety evaluation. The validation results establish the credibility of the calculational tools for use in evaluating a particular application. Validation of the calculational tools is addressed in several American National Standards Institute/American Nuclear Society (ANSI/ANS) standards, with ANSI/ANS-8.1 being the most relevant. Documentation of the validation is a required part of all safety analyses involving significant quantities of fissile materials. In the case of transportation of fissile materials, the safety analysis report for packaging (SARP) must contain a thorough discussion of benchmark experiments, detailing how the experiments relate to the significant packaging and contents materials (fissile, moderating, neutron absorbing) within the package. The experiments recommended in this paper are needed to address certain areas related to transportation of unirradiated fissile materials in drum-type containers (packagings) for which current data are inadequate or are lacking

76 FR 51358 - National Nuclear Security Administration Amended Record of Decision: Disposition of Surplus...

Science.gov (United States)

2011-08-18

... DEPARTMENT OF ENERGY National Nuclear Security Administration Amended Record of Decision... National Nuclear Security Administration (NNSA), a semi- autonomous agency within the U.S. Department of... Manager, Office of Fissile Materials Disposition, National Nuclear Security Administration, U.S...

Communicating with the public on nuclear materials disposition issues

International Nuclear Information System (INIS)

Stevenson, G.B.; Wherley, P.

1995-01-01

The storage and disposition of weapons grade fissile materials involves complex technical issues. The goal of reaching consensus on the best method or methods for storing and ultimately disposing of these materials can only be achieved after an open public discussion of all reasonable alternatives. The US Department of Energy considered a number of factors in developing a program for public involvement. These factors included defining the affected public, public knowledge about the proposed action, decision to be made, availability of pertinent information, current public perceptions, and responding to public input. Based upon an analysis of these factors, three primary techniques were selected for communicating with the public. The techniques are distribution of a quarterly newsletter, establishment of an electronic bulletin board, and holding periodic conference calls and public meetings. The newsletter is designed to reach the widest segment of the public and to be meaningful regardless of the reader's level of familiarity with the project. Periodic conference calls and meeting are used to reach the members of the public who have a real but periodic interest in the issues. The electronic bulletin board is used to communicate with a core group of stakeholders who have a continuing high interest in the total storage and disposition program. Initial indications are that these techniques are effective in reaching a wide segment of the public on highly technical and complex questions related to weapons grade nuclear materials. The effectiveness is not the result of these being new techniques but rather using each technique, to the maximum extent possible, to provide open, on-going, two way communications

Repository for fissile materials

International Nuclear Information System (INIS)

Gablin, K.A.

1976-01-01

A repository for holding and storing fissile or other hazardous materials either under or above the ground is provided by enclosing one or more inner containers, such as standard steel drums, in a larger, corrosion-resistant outer shell, with a layer of foamed polyurethane occupying the space therebetween. The polyurethane foam is free of voids at its interfaces with the inner container and outer shell, and adheres to and reinforces same to provide a stress skin structure. Protection is afforded by the chemical and physical characteristics of the polyurethane foam against destructive influences such as water vapor intrusion, package leakage and damaging effects of the environment, such as freezing, electrolysis, chemical and bacterial action. The outer shell is shaped to conform generally to the shape of the inner container and is made of a tube of bituminized fiber material with endcaps of exterior grade plywood treated with wood preservative. A quantity of fluorescein dye is positioned within the inner container for monitoring each package for leakage

Contribution to fissile materials transportation in transit storage

International Nuclear Information System (INIS)

Silva, Teresinha de Moraes da

2005-01-01

The national and international standards for the transportation of fissile materials establish two indexes: Transport Index (Tl) and Criticality Safety Index (ISC). Besides, in non-exclusive transit, the largest of these indexes cannot overtake the value 50. Considering several groups to be transported, the sum of the transportation indexes cannot overtake 200 and the distance between them should be 6 meters This work aimed, as a primary target, to verify when an index is superior to another, in relation to the fissile materials studied, i.e., uranium oxides UO 2 , U 3 O 8 and uranium silicide U 3 Si 2 , taking into account the different enrichment grades. The result found is that the criticality safety index is always greater. As a second goal, it was tried to verify if there is any alteration in the case of these compounds aging process, i.e., alteration in transport index (Tl) due to gamma radiation of daughters radioisotopes in secular equilibrium. No alteration, was verified as the daughters contribution although considerable related to the transport index is very small concerning the criticality safety index. As a third target, it was tried to justify a distance equal to 6 meters, between each group of fissile material. The result showed that, in air media, the distance of 1 meter is sufficient, except for the UO 2 compound at 100% of enrichment, which reaches 2 meter while in the water means the distance of 40cm is enough for the compounds studied. This fact is of great importance when the cost of the necessary area in the transportation and storage is taken into consideration. (author)

Characterizing Surplus US Plutonium for Disposition - 13199

Energy Technology Data Exchange (ETDEWEB)

Allender, Jeffrey S. [Savannah River National Laboratory, Aiken SC 29808 (United States); Moore, Edwin N. [Moore Nuclear Energy, LLC, Savannah River Site, Aiken SC 29808 (United States)

2013-07-01

The United States (US) has identified 61.5 metric tons (MT) of plutonium that is permanently excess to use in nuclear weapons programs, including 47.2 MT of weapons-grade plutonium. Surplus inventories will be stored safely by the Department of Energy (DOE) and then transferred to facilities that will prepare the plutonium for permanent disposition. The Savannah River National Laboratory (SRNL) operates a Feed Characterization program for the Office of Fissile Materials Disposition (OFMD) of the National Nuclear Security Administration (NNSA) and the DOE Office of Environmental Management (DOE-EM). SRNL manages a broad program of item tracking through process history, laboratory analysis, and non-destructive assay. A combination of analytical techniques allows SRNL to predict the isotopic and chemical properties that qualify materials for disposition through the Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF). The research also defines properties that are important for other disposition paths, including disposal to the Waste Isolation Pilot Plant (WIPP) as transuranic waste (TRUW) or to high-level waste (HLW) systems. (authors)

Fissile materials from nuclear arms reductions: A question of disposition

International Nuclear Information System (INIS)

Sutcliffe, W.G.

1991-01-01

This Session, 35T-2, of the Annual Meeting of the American Association for the Advancement of Science (AAAS) was held on February 18, 1991. The papers presented during this session covered a variety of issues and technologies concerning the disposition of the highly enriched uranium and plutonium salvaged from retired nuclear warheads. However, circumstances, including the amount of time available for the session, imposed limitations on the number and breadth of these papers. A comprehensive study of this topic should include a broader range of papers. This session included a paper on molten salt reactors designed to use highly enriched uranium or plutonium as fuel. Other options for the disposal of plutonium, such as transmutation using accelerators and underground vitrification using nuclear explosions, were not discussed during this session, but need to be considered. Individual papers are indexed separately

Los Alamos National Laboratory summary plan to fabricate mixed oxide lead assemblies for the fissile material disposition program

International Nuclear Information System (INIS)

Buksa, J.J.; Eaton, S.L.; Trellue, H.R.; Chidester, K.; Bowidowicz, M.; Morley, R.A.; Barr, M.

1997-12-01

This report summarizes an approach for using existing Los Alamos National Laboratory (Laboratory) mixed oxide (MOX) fuel-fabrication and plutonium processing capabilities to expedite and assure progress in the MOX/Reactor Plutonium Disposition Program. Lead Assembly MOX fabrication is required to provide prototypic fuel for testing in support of fuel qualification and licensing requirements. It is also required to provide a bridge for the full utilization of the European fabrication experience. In part, this bridge helps establish, for the first time since the early 1980s, a US experience base for meeting the safety, licensing, safeguards, security, and materials control and accountability requirements of the Department of Energy and Nuclear Regulatory Commission. In addition, a link is needed between the current research and development program and the production of disposition mission fuel. This link would also help provide a knowledge base for US regulators. Early MOX fabrication and irradiation testing in commercial nuclear reactors would provide a positive demonstration to Russia (and to potential vendors, designers, fabricators, and utilities) that the US has serious intent to proceed with plutonium disposition. This report summarizes an approach to fabricating lead assembly MOX fuel using the existing MOX fuel-fabrication infrastructure at the Laboratory

Los Alamos National Laboratory summary plan to fabricate mixed oxide lead assemblies for the fissile material disposition program

Energy Technology Data Exchange (ETDEWEB)

Buksa, J.J.; Eaton, S.L.; Trellue, H.R.; Chidester, K.; Bowidowicz, M.; Morley, R.A.; Barr, M.

1997-12-01

This report summarizes an approach for using existing Los Alamos National Laboratory (Laboratory) mixed oxide (MOX) fuel-fabrication and plutonium processing capabilities to expedite and assure progress in the MOX/Reactor Plutonium Disposition Program. Lead Assembly MOX fabrication is required to provide prototypic fuel for testing in support of fuel qualification and licensing requirements. It is also required to provide a bridge for the full utilization of the European fabrication experience. In part, this bridge helps establish, for the first time since the early 1980s, a US experience base for meeting the safety, licensing, safeguards, security, and materials control and accountability requirements of the Department of Energy and Nuclear Regulatory Commission. In addition, a link is needed between the current research and development program and the production of disposition mission fuel. This link would also help provide a knowledge base for US regulators. Early MOX fabrication and irradiation testing in commercial nuclear reactors would provide a positive demonstration to Russia (and to potential vendors, designers, fabricators, and utilities) that the US has serious intent to proceed with plutonium disposition. This report summarizes an approach to fabricating lead assembly MOX fuel using the existing MOX fuel-fabrication infrastructure at the Laboratory.

Fissile materials principles of criticality safety in handling and processing

International Nuclear Information System (INIS)

1976-01-01

This Swedish Standard consists of the English version of the International Standard ISO 1709-1975-Nuclear energy. Fissile materials. Principles of criticality safety in handling and processing. (author)

Fissile materials and international security in the post-Cold War world

International Nuclear Information System (INIS)

Anon.

1996-01-01

It is essential that members of industry, government and international organizations be able to come together to discuss the latest developments in this vital field at events such as this. Given the number of years this organization has devoted to the issue, the INMM must find it interesting that the control of fissile materials has become such a high-profile issue in the policy and political communities. But, this evolution in policy is a natural outgrowth of the changing world situation. While just 10 years ago the US and Soviet Union were churning out the fissile materials needed for weapons, today these former rivals are working together, hand in hand, to corral the danger posed by these materials. And, while it is clear that the world no longer lives on the edge of nuclear war, the nuclear danger still exists, though in a less obvious and perhaps more insidious form. It is a great challenge in this post-Cold War world to contain this nuclear threat. It is prudent and necessary for the US to be in the forefront of efforts to address and tame this problem. The fundamental threat posed by the proliferation of nuclear weapons and materials is a direct challenge to US and world security. President Clinton has clearly recognized the changed nature of the nuclear danger. To meet this challenge, he has labored to put in place a comprehensive and integrated plan for addressing this threat. The US Department of Energy has a unique role in this effort because, as an institution with many decades of experience in fissile material matters, it is able to provide expertise and technical analyses that are essential in defining and implementing policy prescriptions. The president's comprehensive plan to prevent nuclear proliferation and reduce the danger posed by weapons-usable nuclear materials has four essential elements: secure existing nuclear material stockpiles; limit fissile material production and use, eliminate warheads, and strengthen the nonproliferation regime

Standard problem exercise to validate criticality codes for large arrays of packages of fissile materials

International Nuclear Information System (INIS)

Whitesides, G.E.; Stephens, M.E.

1986-01-01

A study has been conducted by an Office of Economic Cooperation and Development-Committee on the Safety of Nuclear Installations (OECD-CSNI) Working Group that examined computational methods used to compute k/sub eff/ for large greater than or equal to5 3 arrays of fissile material (in which each unit is a substantial fraction of a critical mass). Five fissile materials that might typically be transported were used in the study. The ''packages'' used for this exercise were simplified to allow studies unperturbed by the variety of structural materials which would exist in an actual package. The only material present other than the fissile material was a variation in the moderator (water) surrounding the fissile material. Consistent results were obtained from calculations using several computational methods. That is, when the bias demonstrated by each method for actual critical experiments was used to ''correct'' the results obtained for systems for which there were no experimental data, there was good agreement between the methods. Two major areas of concern were raised by this exercise. First, the lack of experimental data for arrays with size greater than 5 3 limits validation for large systems. Second, there is a distinct possibility that the comingling of two shipments of unlike units could result in a reduction of the safety margins. Additional experiments and calculations will be required to satisfactorily resolve the remaining questions regarding the safe transport of large arrays of fissile materials

Criticality Safety in the Handling of Fissile Material. Specific Safety Guide

Energy Technology Data Exchange (ETDEWEB)

NONE

2014-05-15

This Safety Guide provides guidance and recommendations on how to meet the relevant requirements for ensuring subcriticality when dealing with fissile material and for planning the response to criticality accidents. The guidance and recommendations are applicable to both regulatory bodies and operating organizations. The objectives of criticality safety are to prevent a self-sustained nuclear chain reaction and to minimize the consequences of this if it were to occur. The Safety Guide makes recommendations on how to ensure subcriticality in systems involving fissile materials during normal operation, anticipated operational occurrences, and, in the case of accident conditions, within design basis accidents, from initial design through commissioning, operation, and decommissioning and disposal.

Reducing nuclear danger through intergovernmental technical exchanges on nuclear materials safety management

International Nuclear Information System (INIS)

Jardine, L.J.; Peddicord, K.L.; Witmer, F.E.; Krumpe, P.F.; Lazarev, L.; Moshkov, M.

1997-01-01

The United States and Russia are dismantling nuclear weapons and generating hundreds of tons of excess plutonium and high enriched uranium fissile nuclear materials that require disposition. The U.S. Department of Energy and Russian Minatom organizations.are planning and implementing safe, secure storage and disposition operations for these materials in numerous facilities. This provides a new opportunity for technical exchanges between Russian and Western scientists that can establish an improved and sustained common safety culture for handling these materials. An initiative that develops and uses personal relationships and joint projects among Russian and Western participants involved in fissile nuclear materials safety management contributes to improving nuclear materials nonproliferation and to making a safer world. Technical exchanges and workshops are being used to systematically identify opportunities in the nuclear fissile materials facilities to improve and ensure the safety of workers, the public, and the environment

Assessment and recommendations for fissile-material packaging exemptions and general licenses within 10 CFR Part 71

International Nuclear Information System (INIS)

Parks, C.V.; Hopper, C.M.; Lichtenwalter, J.L.

1998-07-01

This report provides a technical and regulatory assessment of the fissile material general licenses and fissile material exemptions within Title 10 of the Code of Federal Regulations Part 71. The assessment included literature studies and calculational analyses to evaluate the technical criteria; review of current industry practice and concerns; and a detailed evaluation of the regulatory text for clarity, consistency and relevance. Recommendations for potential consideration by the Nuclear Regulatory Commission staff are provided. The recommendations call for a simplification and consolidation of the general licenses and a change in the technical criteria for the first fissile material exemptions

Gamma ray absorption of cylindrical fissile material with dual shields

International Nuclear Information System (INIS)

Wu Chenyan; Cheng Yiying; Huang Yongyi; Lu Fuquan; Yang Fujia

2005-01-01

This work analyzed the gamma ray attenuation effect from the self-absorption and shield attenuation perspectively. An exact mathematical equation was given for the geometric factor of the cylindrical fissile material with dual shields. In addition, several approximation approaches suitable for real situation were discussed, especially in the radial and axial directions of the cylinders, since the G-factors have simple forms. Then the space distribution patterns of the G-factor were analyzed based on numerical result and effective ways to solved the geometric information of the cylindrical fissile material, the radii and the heights, were deduced. This method was checked and verified by numerical calculation. Because of the efficiency of the method, it is ideal for application in real situations, such as nuclear safeguards, which demands speed of detection and accuracy of geometric analysis. (authors)

User manual of FUNF code for fissile material data calculation

International Nuclear Information System (INIS)

Zhang, Jingshang

2006-03-01

The FUNF code (2005 version) is used to calculate fast neutron reaction data of fissile materials with incident energies from about 1 keV up to 20 MeV. The first version of the FUNF code was completed in 1994. the code has been developed continually since that time and has often been used as an evaluation tool for setting up CENDL and for analyzing the measurements of fissile materials. During these years many improvements have been made. In this manual, the format of the input parameter files and the output files, as well as the functions of flag used in FUNF code, are introduced in detail, and the examples of the format of input parameters files are given. FUNF code consists of the spherical optical model, the Hauser-Feshbach model, and the unified Hauser-Feshbach and exciton model. (authors)

India and the fissile material cut-off treaty: policy options

International Nuclear Information System (INIS)

Nayan, Rajiv

2011-01-01

The international community inside and outside the Conference of Disarmament is underscoring the need for concluding a fissile material cut-off treaty (FMCT). The Indian government, for a long period, has been sponsoring the idea. Notwithstanding the international stagnation, the issue has been instigating periodic debate in India on the Indian approach. The periodic revival of the issue requires that India revisit its policy on fissile material production as well as its approach towards a possible EVICT. This article examines the question: should India's approach to conclude an FMCT be within the UN institutional framework? The new international reality is pushing for a new context, new realignments and a fresh outlook for an FMCT. India should take its own time to support conclusion of an FMCT so that its national interests and security are not adversely affected. (author)

49 CFR 173.420 - Uranium hexafluoride (fissile, fissile excepted and non-fissile).

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Uranium hexafluoride (fissile, fissile excepted....420 Uranium hexafluoride (fissile, fissile excepted and non-fissile). (a) In addition to any other... non-fissile uranium hexafluoride must be offered for transportation as follows: (1) Before initial...

Surplus plutonium disposition environmental impact statement. Public scoping meeting: Comment summary report

International Nuclear Information System (INIS)

1997-09-01

The Department of Energy (DOE) issued a Record of Decision for the Storage and Disposition of Weapons-Usable Fissile Materials Programmatic Environmental Impact Statement (S ampersand D PEIS) (DOE/EIS-0229) on January 14, 1997. In that Record of Decision, DOE stated its decision to pursue a strategy for plutonium disposition that allows for immobilization of surplus weapons plutonium in glass or ceramic forms and irradiating the surplus plutonium as mixed oxide (MOX) fuel in existing reactors, while reserving the option to immobilize all the surplus weapons plutonium. The Department also decided that the extent to which either or both of these disposition approaches would ultimately be deployed would depend in part upon future National Environmental Policy Act (NEPA) review for surplus weapons plutonium disposition. On May 22, 1997, DOE published in the Federal Register (62 FR 28013) a Notice of Intent to prepare an environmental impact statement (tiered from the S ampersand D PEIS) on the disposition of United States' surplus weapons-usable plutonium. The purpose of the Notice of Intent was to describe DOE's proposed action, to solicit public input, and to announce the schedule for the public scoping meetings. During the public scoping period (May 22 - July 22, 1997), the public was invited to submit written comments by U.S. mail, fax, or through the Office of Fissile Materials Disposition's Website, as well as to provide oral comments by voicemail or by participating in public scoping meetings. Written and oral comments on the scope of the SPD EIS that were submitted during the formal comment period have been uniquely identified and have become part of the official record. This is the case whether the comments were submitted via U.S. mail, fax, website, toll-free telephone number, or through participation at a public scoping meeting

Self Shielding in Nuclear Fissile Assay Using LSDS

International Nuclear Information System (INIS)

Lee, Yong Deok; Park, Chang Je; Park, Geun Il; Song, Kee Chan

2012-01-01

The new technology for isotopic fissile material contents assay is under development at KAERI using lead slowing down spectrometer(LSDS). LSDS is very sensitive to distinguish fission signals from each fissile isotope in spent and recycled fuel. The accumulation of spent fuel is current big issue. The amount of spent fuels will reach the maximum storage capacity of the pools soon. Therefore, an interim storage must be searched and it should be optimized in design by applying accurate fissile content. When the storage has taken effect, all the nuclear materials must be also specified and verified for safety, economics and management. Generally, the spent fuel from PWR has unburned ∼1 % U235, produced ∼0.5 % plutonium from decay chain, ∼3 % fission products, ∼ 0.1 % minor actinides (MA) and uranium remainder. About 1.5 % fissile materials still exist in the spent fuel. Therefore, for reutilization of fissile materials in spent fuel at SFR, resource material is produced through pyro process. Fissile material contents in resource material must be analyzed before fabricating SFR fuel for reactor safety and economics. In assay of fissile content of spent fuel and recycled fuel, intense radiation background gives limitation on the direct analysis of fissile materials. However, LSDS is not influenced by such a radiation background in fissile assay. Based on the decided geometry setup, self shielding parameter was calculated at the fuel assay zone by introducing spent fuel or pyro produced nuclear material. When nuclear material is inserted into the assay area, the spent fuel assembly or pyro recycled fuel material perturbs the spatial distribution of the slowing down neutrons in lead and the prompt fast fission neutrons produced by fissile materials are also perturbed. The self shielding factor is interpreted as that how much of absorption is created inside the fuel area when it is in the lead. Self shielding effect provides a non-linear property in the isotopic

Warheads and Fissile Materials:Declarations and Counting

International Nuclear Information System (INIS)

Sutcliffe, W.G.

1991-01-01

This paper reviews some of the issues about verifying the dismantlement of nuclear warheads and controlling nuclear materials in the context of arms control objectives. It is asserted that information about the stockpiles of nuclear warheads and materials is necessary to analyze the impacts and verification requirements of arms control measures including warhead dismantlement and fissile material controls. It is proposed that the US and the Soviets engage in a series of declarations about their stockpiles of nuclear weapons and materials. It is also asserted that currently it is more important to verify that warheads are retired to safe, secure facilities than to verify their dismantlement. It is proposed that production of new or rebuilt warheads be limited to less than the number retired each year. Verifying the number of new and rebuilt warheads deployed and the number retired avoids many of the difficulties in verifying dismantlement and material controls

LSDS Development for Isotopic Fissile Assay in Spent Fuel

Energy Technology Data Exchange (ETDEWEB)

Lee, Yong Deok; Park, Chang Je; Park, Geun Il; Lee, Jung Won; Song, Kee Chan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2011-07-01

As an option to reduce a spent fuel and reuse an existing fissile material in spent fuel, sodium fast reactor SFR program linked with pyro-processing is under development in KAERI. A uranium-TRU mixture through a pyro-process is used to fabricate SFR fuel. An assay of isotopic fissile content plays an important role in an optimum design of storage site and reuse of fissile materials of spent fuel. Lead slowing down spectrometer LSDS is being developed in KAERI to analyze isotopic fissile material content. LSDS has several features: direct fissile assay, near real time fissile assay, no influence from radiation background, fissile isotopic assay and applicable to spent fuel and recycled fuel. Based on the designed geometry, neutron energy resolution was investigated. The neutron energy spectrum was analyzed as well. Spent fuel emits large number of neutrons by spontaneous fission. Neutron generator must overcome the neutron background to get the pure fission signals from fissile materials. Neutron generator is planned to have compact system with one section electron linac which is easy maintenance, less cost and high neutron yield. The LSD has the power to resolve the fission characteristics from each fissile material. This feature can analyze the content of isotopic fissile. From 1keV to 0.1eV energy range, the energy resolution is enough to get the individual fissile fission signatures. The dominant fission signature is shown below 1eV for each fissile isotope. The neutron generation system with target was designed to get fission signals by fissile materials. The system was decided to overcome neutron backgrounds and to get good counting statistics. Finally, an accurate fissile material content will contribute to safety of spent fuel reuse in future nuclear energy system and optimum design of spent fuel storage site. Additionally, an accurate fissile material content will increase international transparence and credibility for the reuse of PWR spent fuel.

LSDS Development for Isotopic Fissile Assay in Spent Fuel

International Nuclear Information System (INIS)

Lee, Yong Deok; Park, Chang Je; Park, Geun Il; Lee, Jung Won; Song, Kee Chan

2011-01-01

As an option to reduce a spent fuel and reuse an existing fissile material in spent fuel, sodium fast reactor SFR program linked with pyro-processing is under development in KAERI. A uranium-TRU mixture through a pyro-process is used to fabricate SFR fuel. An assay of isotopic fissile content plays an important role in an optimum design of storage site and reuse of fissile materials of spent fuel. Lead slowing down spectrometer LSDS is being developed in KAERI to analyze isotopic fissile material content. LSDS has several features: direct fissile assay, near real time fissile assay, no influence from radiation background, fissile isotopic assay and applicable to spent fuel and recycled fuel. Based on the designed geometry, neutron energy resolution was investigated. The neutron energy spectrum was analyzed as well. Spent fuel emits large number of neutrons by spontaneous fission. Neutron generator must overcome the neutron background to get the pure fission signals from fissile materials. Neutron generator is planned to have compact system with one section electron linac which is easy maintenance, less cost and high neutron yield. The LSD has the power to resolve the fission characteristics from each fissile material. This feature can analyze the content of isotopic fissile. From 1keV to 0.1eV energy range, the energy resolution is enough to get the individual fissile fission signatures. The dominant fission signature is shown below 1eV for each fissile isotope. The neutron generation system with target was designed to get fission signals by fissile materials. The system was decided to overcome neutron backgrounds and to get good counting statistics. Finally, an accurate fissile material content will contribute to safety of spent fuel reuse in future nuclear energy system and optimum design of spent fuel storage site. Additionally, an accurate fissile material content will increase international transparence and credibility for the reuse of PWR spent fuel

The role of congress in future disposal of fissile materials from dismantled nuclear weapons

International Nuclear Information System (INIS)

Donnelly, W.H.; Davis, Z.S.

1991-01-01

Assuming the Soviet Union remains intact as a major power and the superpowers do not retrogress to a new Cold War era, it is likely that the United States and the Soviet Union will eventually agree to deep cuts in their nuclear arsenals. Future arms control agreements may be coupled with companion agreements to stop production of fissile materials for nuclear weapons, to dismantle the warheads of the nuclear weapons, and to dispose of their fissile materials to prevent reuse in new warheads. Such agreements would be negotiated by the U.S. executive branch but probably would require ratification, funding, and enabling legislation from the U.S. Congress if they are to succeed. There follows a brief review of the ideas for disposal of fissile materials from dismantled nuclear warheads and the potential role and influence of the Congress in the negotiation, ratification, and implementation of U.S.-Soviet agreements for such disposal

Materials technology for accelerator production of fissile isotopes

International Nuclear Information System (INIS)

Horak, J.A.

1978-02-01

The materials used for the accelerator production of fissile isotopes must enable the facility to achieve maximum fuel production at a minimum cost. Neutron production in the target would be maximized by use of thorium cooled with Pb--56 percent Bi or with sodium. The thorium should be ion-plated with approximately 1 mil of nickel or stainless steel for retention of fission products. The target container will have to be replaced at frequent intervals because of the copious quantities of neutronically produced helium and hydrogen in the container. Replacement would coincide with shutdown of the facility for the removal of the fissile material produced. If sodium is used to cool both the target and fertile blanket, a simple basket-type target container could be used. This would greatly reduce radiation effects in the target container. Type 316 stainless steel or V--20 wt percent Ti should perform satisfactorily as a target container. The fertile blanket should be 233 Th or 238 U that is coated with approximately 1 mil of nickel or stainless steel and cooled with sodium. The blanket container could be an austenitic stainless steel such as type 304 or 316; some ferritic alloys may also provide a satisfactory blanket container. 31 references

Disposition of excess weapons plutonium from dismantled weapons

International Nuclear Information System (INIS)

Jardine, L.J.

1997-01-01

With the end of the Cold War and the implementation of various nuclear arms reduction agreements, US and Russia have been actively dismantling tens of thousands of nuclear weapons. As a result,large quantities of fissile materials, including more than 100 (tonnes?) of weapons-grade Pu, have become excess to both countries' military needs. To meet nonproliferation goals and to ensure the irreversibility of nuclear arms reductions, this excess weapons Pu must be placed in secure storage and then, in timely manner, either used in nuclear reactors as fuel or discarded in geologic repositories as solid waste. This disposition in US and Russia must be accomplished in a safe, secure manner and as quickly as practical. Storage of this Pu is a prerequisite to any disposition process, but the length of storage time is unknown. Whether by use as fuel or discard as solid waste, disposition of that amount of Pu will require decades--and perhaps longer, if disposition operations encounter delays. Neither US nor Russia believes that long-term secure storage is a substitute for timely disposition of excess Pu, but long-term, safe, secure storage is a critical element of all excess Pu disposition activities

Automated monitoring of fissile and fertile materials in incinerator residue

International Nuclear Information System (INIS)

Schoenig, F.C. Jr.; Glendinning, S.G.; Tunnell, G.W.; Zucker, M.S.

1986-01-01

This patent describes an apparatus for determining the fissile and fertile material content of incinerator residue contained in a manipulatable container. The apparatus comprises a main body member formed of neutron moderating material and formed with a well for receiving the container; a first plug formed of neutron reflecting material for closing the top of the well; and a second plug containing a first neutron source for alternatively closing the top of the well and for directing neutrons into the well. It also includes a second neutron source selectively positionable in the bottom of the well for directing neutrons into the well; manipulating means for placing the container in the well and removing the container therefrom and for selectively placing one of the first and second plugs in the top of the well. Neutron detectors are positioned within the neutron moderating material of the main body member around the sides of the well. At least one gamma ray detector is positioned adjacent the bottom of the well. A means receives and processes the signals from the neutron and gamma ray detectors when the container is in the well for determining the fissile and fertile material content of the incinerator residue in the container

Actualization of physical-chemical properties and criticality data of specific fissile materials

International Nuclear Information System (INIS)

Strauch, V.; Deutsch, K.H.

1991-09-01

The purpose of this project is to update the criticality curves contained in DIN 25 403, Parts 2-8. This report contains criticality data for aqueous uranium and plutonium systems of various concentrations for spherical, cylindrical and layer geometries. The critical dimensions were calculated with the single dimensional transport code XSDRNPM-S and the 27 group-library from Scale 3.1. A 30 cm thick water reflector was taken into account. The critical masses were obtained by multiplying the volume of a critical sphere with the fissile material concentration. The moderator/fissile material relationship for each of the investigated concentration ranges were described. Checks were made using experiments with comparable fissile material systems. Due to the complex geometry of some of the chosen experiments some calculation checks were carried out using the Monte-Carlo-Codes KENO IV-S and Va. The calculation results compared very well with the experiments. Comparison of the results with the currently valid DIN curves does not show any serious differences. The new values lie however slightly below the current values and therefore represent conservative values, so that the criticality curves of DIN 25 403, Parts 2-6 and 8 should be replaced. (orig./HP) [de

Screening of IAEA environmental samples for fissile material content

International Nuclear Information System (INIS)

Hembree, Doyle M. Jr.; Carter, Joel A.; Devault, Gerald L.; Whitaker, J. Michael; Glasgow, David

2001-01-01

Full text: Analysis of environmental samples for the International Atomic Energy Agency (IAEA) Strengthened Safeguards Systems program requires that stringent measures be taken to control contamination. To facilitate contamination control, it is extremely useful to have some estimate of the fissile content of a given sample prior to beginning sample preparation and analysis. This is particularly true for laboratories that employ clean rooms during sample preparation. A review of the analytical results for samples submitted between January 1, 1999 and September 1, 2000 revealed that the total uranium content values ranged from 0.2 to greater than 500,000 ng/sample. Poor estimates of the uranium or plutonium content in the samples have caused some of the laboratories in the IAEA Network of Analytical Laboratories (NWAL) to experience clean laboratory contamination, sample cross contamination, and non-ideal uranium spike additions. This has led to significant increases in analysis costs (e.g., recertification of clean rooms after removing contamination, and rerunning samples) and degradation in data quality. A number of methods have been proposed for screening environmental samples for fissile material content, including gamma spectrometry, x-ray fluorescence, kinetic phosphorimetry (KPA), and inductively coupled plasma-mass spectrometry (ICP-MS). Gamma spectrometry and x-ray fluorescence are suitable for screening samples with microgram or greater quantities of uranium. ICP-MS and KPA are used successfully in some DOE NWAL laboratories to screen environmental samples. A neutron activation analysis (NAA) method that offers numerous advantages over other screening techniques for environmental samples has recently been proposed. Fissile materials such as 239 Pu and 235 U can be made to undergo fission in the intense neutron field to which they are exposed during neutron activation analysis (NAA). Some of the fission products emit neutrons referred to as 'delayed

Fissile material and international security in the post-Cold War world

International Nuclear Information System (INIS)

Luongo, K.N.

1995-01-01

Given the number of years this organization has devoted to the issue, the INMM must find it quite interesting that the control of fissile materials has become such a high profile issue in the policy and political communities. But, this evolution in policy is a natural outgrowth of the changing world situation. While just ten years ago the United States and the Soviet Union were churning out the fissile materials needed for weapons, today these former rivals are working together, hand in hand, to corral the danger posed by these materials. And, while it is clear that the world no longer lives on the edge of nuclear war, the nuclear danger still exists, though in a less obvious and perhaps more insidious form. It is a great challenge in this post Cold War-world to contain this nuclear threat. It is prudent and necessary for the United States to be in the forefront of efforts to address and tame this problem. The fundamental threat posed by the proliferation of nuclear weapons and materials is a direct challenge to US and world security. President Clinton has clearly recognized the changed nature of the nuclear danger. To meet this challenge, he also labored to put in place a comprehensive and integrated plan for addressing this threat. The Department of Energy has a unique role in this effort because, as an institution with man decades of experience in fissile material matters, it is able to provide expertise and technical analyses which are essential in defining and implementing policy prescriptions. The President's comprehensive plan to prevent nuclear proliferation and reduce the danger posed by weapons-usable nuclear materials has four essential elements: (1) secure existing stockpiles; (2) limit production and use; (3) eliminate warheads; and (4) strengthen the nonproliferation regime

Fissile Content Assay of Spent Fuel Using LSDS System

International Nuclear Information System (INIS)

Jeon, Ju Young; Lee, Yong Deok; Park, Chang Je

2016-01-01

About 1.5 % fissile materials still exist in the spent fuel. Therefore, for reutilization of fissile materials in spent fuel at SFR, resource material is produced through the pyro process. Fissile material contents in the resource material must be analyzed before fabricating SFR fuel for reactor safety and economics. The new technology for an isotopic fissile material content assay is under development at KAERI using a lead slowing down spectrometer (LSDS). LSDS is very sensitive to distinguish fission signals from each fissile isotope in spent and recycled fuel. In an assay of fissile content of spent fuel and recycled fuel, an intense radiation background gives limits the direct analysis of fissile materials. However, LSDS is not influenced by such a radiation background in a fissile assay. Based on the decided LSDS geometry set up, a self shielding parameter was calculated at the fuel assay zone by introducing spent fuel or pyro produced nuclear material. When nuclear material is inserted into the assay area, the spent fuel assembly or pyro recycled fuel material perturbs the spatial distribution of slowing down neutrons in lead and the prompt fast fission neutrons produced by fissile materials are also perturbed. The self shielding factor is interpreted as how much of the absorption is created inside the fuel area when it is in the lead. The self shielding effect provides a non-linear property in the isotopic fissile assay. When the self shielding is severe, the assay system becomes more complex and needs a special parameter to treat this non linear effect. Additionally, an assay of isotopic fissile content will contribute to an accuracy improvement of the burn-up code and increase the transparency and credibility for spent fuel storage and usage, as internationally increasing demand. The fissile contents result came out almost exactly with relative error ∼ 2% in case of Pu239, Pu241 for two different plutonium contents. In this study, meaningful results were

Nonintrusive verification attributes for excess fissile materials

International Nuclear Information System (INIS)

Nicholas, N.J.; Eccleston, G.W.; Fearey, B.L.

1997-10-01

Under US initiatives, over two hundred metric tons of fissile materials have been declared to be excess to national defense needs. These excess materials are in both classified and unclassified forms. The US has expressed the intent to place these materials under international inspections as soon as practicable. To support these commitments, members of the US technical community are examining a variety of nonintrusive approaches (i.e., those that would not reveal classified or sensitive information) for verification of a range of potential declarations for these classified and unclassified materials. The most troublesome and potentially difficult issues involve approaches for international inspection of classified materials. The primary focus of the work to date has been on the measurement of signatures of relevant materials attributes (e.g., element, identification number, isotopic ratios, etc.), especially those related to classified materials and items. The authors are examining potential attributes and related measurement technologies in the context of possible verification approaches. The paper will discuss the current status of these activities, including their development, assessment, and benchmarking status

Ensuring the 50 year life of a fissile material container

International Nuclear Information System (INIS)

Glass, R.E.; Towne, T.L.

1997-12-01

Sandia was presented with an opportunity in 1993 to design containers for the long term storage and transport of fissile material. This program was undertaken at the direction of the US Department of Energy and in cooperation with Lawrence Livermore National Laboratory and Los Alamos National Laboratory which were tasked with developing the internal fixturing for the contents. The hardware is being supplied by Allied Signal Federal Manufacturing and Technologies, and the packaging will occur at Mason and Hangar Corporation's Pantex Plant. The unique challenge was to design a container that could be sealed with the fissile material contents; and, anytime during the next 50 years, the container could be transported with only the need for the pre-shipment leak test. This required not only a rigorous design capable of meeting the long term storage and transportation requirements, but also resulted in development of a surveillance program to ensure that the container continues to perform as designed over the 50-year life. This paper addresses the design of the container, the testing that was undertaken to demonstrate compliance with US radioactive materials transport regulations, and the surveillance program that has been initiated to ensure the 50-year performance

Proceedings from the Fissile Material Cut-off seminar in Stockholm

International Nuclear Information System (INIS)

Arbman, G.

1998-01-01

The Swedish Defence Research Establishment hosted an international expert seminar on the subject of verifying a prohibition of the production of fissile material for nuclear weapons purpose (cut-off) in Stockholm, June 3-5 1998. The objective of the seminar was to provide an opportunity for informal discussions among scientific and technical experts on various technical matters relating to the verification of a future Fissile Material Cut-off Treaty (FMCT). A stated aim of the seminar was to keep issues of scope to a minimum. Invited speakers and commentators were given an opportunity to present their views as written contributions. The present seminar proceedings are essentially the result of these views. In addition, short summaries of the discussions following each session are included. Although an attempt was made to be as complete and accurate as possible in reproducing these discussions, the editors apologise if some important points or statements have been omitted. If so, the main reason is that the documentation of the discussions were based on written notes, not taped recordings. Eight longer contributions have been separately indexed

Proceedings from the Fissile Material Cut-off seminar in Stockholm

Energy Technology Data Exchange (ETDEWEB)

Arbman, G. [ed.

1998-07-01

The Swedish Defence Research Establishment hosted an international expert seminar on the subject of verifying a prohibition of the production of fissile material for nuclear weapons purpose (cut-off) in Stockholm, June 3-5 1998. The objective of the seminar was to provide an opportunity for informal discussions among scientific and technical experts on various technical matters relating to the verification of a future Fissile Material Cut-off Treaty (FMCT). A stated aim of the seminar was to keep issues of scope to a minimum. Invited speakers and commentators were given an opportunity to present their views as written contributions. The present seminar proceedings are essentially the result of these views. In addition, short summaries of the discussions following each session are included. Although an attempt was made to be as complete and accurate as possible in reproducing these discussions, the editors apologise if some important points or statements have been omitted. If so, the main reason is that the documentation of the discussions were based on written notes, not taped recordings. Eight longer contributions have been separately indexed.

Increasing transparency of nuclear-warhead and fissile-material stocks as a step toward disarmament -- Proposals for the NPT PrepCom, Geneva

International Nuclear Information System (INIS)

2013-04-01

These proposals made by the International Panel on Fissile Materials IPFM at a conference in Geneva, Switzerland, in April 2013 discuss how increasing transparency can help disarmament efforts. After a short introduction to IPFM and its mission, the action plan on nuclear disarmament is looked at and the various nations involved are listed. A set of baseline declarations proposed are discussed. These include warhead stocks, potential new declarations and fissile material stocks. Monitoring by the International Atomic Energy Authority IAEA is also reviewed. Preparations for future declarations concerning warhead and delivery systems locations, stockpile histories and fissile material production and disposal aspects are reported on. Finally, co-operative verification projects, warhead dismantlement and past fissile material production are examined

New Technology For Fissile Assay In Spent Fuel Using LSDS

International Nuclear Information System (INIS)

Lee, Yongdeok; Park, Changje; Park, Geunil; Lee, Jungwon; Song, Keechan

2012-01-01

The principle of LSDS is very simple. The interrogated neutron induces energy dependent characteristic fission from fissile materials in spent fuel. The fission threshold detector screens the prompt fast fission neutrons from background and fissionable materials. However, intense source neutron is necessary to overcome radiation background. The detected signals have a direct relationship to the content of each fissile material. The isotopic fissile assay using LSDS is applicable for optimum design of spent fuel storage and management, quality assurance of recycled nuclear material, maximization of burnup credit. Another important application is verity burnup code and provide correction factor for improving the fissile material content, fission product correction factor for improving the fissile material content, fission product content and theoretical burnup. Additionally, the isotopic fissile content assay will increase the transparence and credibility for spent fuel storage and its re-utilization, as internationally demanded

Surplus plutonium disposition draft environmental impact statement. Summary

International Nuclear Information System (INIS)

1998-07-01

On May 22, 1997, DOE published a Notice of Intent (NOI) in the Federal Register (62 Federal Register 28009) announcing its decision to prepare an environmental impact statement (EIS) that would tier from the analysis and decisions reached in connection with the Storage and Disposition of Weapons-Usable Fissile Materials Final Programmatic EIS (Storage and Disposition PEIS). DOE's disposition strategy allows for both the immobilization of surplus plutonium and its use as mixed oxide (MOX) fuel in existing domestic, commercial reactors. The disposition of surplus plutonium would also involve disposal of the immobilized plutonium and MOX fuel (as spent nuclear fuel) in a geologic repository. The Surplus Plutonium Disposition Environmental Impact Statement analyzes alternatives that would use the immobilization approach (for some of the surplus plutonium) and the MOX fuel approach (for some of the surplus plutonium); alternatives that would immobilize all of the surplus plutonium; and the No Action Alternative. The alternatives include three disposition facilities that would be designed so that they could collectively accomplish disposition of up to 50 metric tons (55 tons) of surplus plutonium over their operating lives: (1) the pit disassembly and conversion facility would disassemble pits (a weapons component) and convert the recovered plutonium, as well as plutonium metal from other sources, into plutonium dioxide suitable for disposition; (2) the immobilization facility would include a collocated capability for converting nonpit plutonium materials into plutonium dioxide suitable for immobilization and would be located at either Hanford or SRS. DOE has identified SRS as the preferred site for an immobilization facility; (3) the MOX fuel fabrication facility would fabricate plutonium dioxide into MOX fuel

Unallocated Off-Specification Highly Enriched Uranium: Recommendations for Disposition

Energy Technology Data Exchange (ETDEWEB)

Bridges, D. N.; Boeke, S. G.; Tousley, D. R.; Bickford, W.; Goergen, C.; Williams, W.; Hassler, M.; Nelson, T.; Keck, R.; Arbital, J.

2002-02-27

The U.S. Department of Energy (DOE) has made significant progress with regard to disposition planning for 174 metric tons (MTU) of surplus Highly Enriched Uranium (HEU). Approximately 55 MTU of this 174 MTU are ''offspec'' HEU. (''Off-spec'' signifies that the isotopic or chemical content of the material does not meet the American Society for Testing and Materials standards for commercial nuclear reactor fuel.) Approximately 33 of the 55 MTU have been allocated to off-spec commercial reactor fuel per an Interagency Agreement between DOE and the Tennessee Valley Authority (1). To determine disposition plans for the remaining {approx}22 MTU, the DOE National Nuclear Security Administration (NNSA) Office of Fissile Materials Disposition (OFMD) and the DOE Office of Environmental Management (EM) co-sponsored this technical study. This paper represents a synopsis of the formal technical report (NNSA/NN-0014). The {approx} 22 MTU of off-spec HEU inventory in this study were divided into two main groupings: one grouping with plutonium (Pu) contamination and one grouping without plutonium. This study identified and evaluated 26 potential paths for the disposition of this HEU using proven decision analysis tools. This selection process resulted in recommended and alternative disposition paths for each group of HEU. The evaluation and selection of these paths considered criteria such as technical maturity, programmatic issues, cost, schedule, and environment, safety and health compliance. The primary recommendations from the analysis are comprised of 7 different disposition paths. The study recommendations will serve as a technical basis for subsequent programmatic decisions as disposition of this HEU moves into the implementation phase.

LLNL MOX fuel lead assemblies data report for the surplus plutonium disposition environmental impact statement

International Nuclear Information System (INIS)

O'Connor, D.G.; Fisher, S.E.; Holdaway, R.

1998-08-01

The purpose of this document is to support the US Department of Energy (DOE) Fissile Materials Disposition Program's preparation of the draft surplus plutonium disposition environmental impact statement. This is one of several responses to data call requests for background information on activities associated with the operation of the lead assembly (LA) mixed-oxide (MOX) fuel fabrication facility. The DOE Office of Fissile Materials Disposition (DOE-MD) has developed a dual-path strategy for disposition of surplus weapons-grade plutonium. One of the paths is to disposition surplus plutonium through irradiation of MOX fuel in commercial nuclear reactors. MOX fuel consists of plutonium and uranium oxides (PuO 2 and UO 2 ), typically containing 95% or more UO 2 . DOE-MD requested that the DOE Site Operations Offices nominate DOE sites that meet established minimum requirements that could produce MOX LAs. LLNL has proposed an LA MOX fuel fabrication approach that would be done entirely inside an S and S Category 1 area. This includes receipt and storage of PuO 2 powder, fabrication of MOX fuel pellets, assembly of fuel rods and bundles, and shipping of the packaged fuel to a commercial reactor site. Support activities will take place within a Category 1 area. Building 332 will be used to receive and store the bulk PuO 2 powder, fabricate MOX fuel pellets, and assemble fuel rods. Building 334 will be used to assemble, store, and ship fuel bundles. Only minor modifications would be required of Building 332. Uncontaminated glove boxes would need to be removed, petition walls would need to be removed, and minor modifications to the ventilation system would be required

Deep borehole disposition of surplus fissile materials-The site selection process

International Nuclear Information System (INIS)

Heiken, G.; WoldeGabriel, G.; Morley, R.; Plannerer, H.

1996-01-01

One option for disposing of excess weapons plutonium is to place it near the base of deep boreholes in stable crystalline rocks. The technology exists to immediately begin the design of this means of disposition and there are many attractive sites available within the conterminous US. The borehole system utilizes mainly natural barriers to preven migration of Pu and U to the Earth's surface. Careful site selection ensures favorable geologic conditions that provide natural long-lived migration barriers; they include deep, extremely stable rock formations, strongly reducing brines that exhibit increasing salinity with depth, and most importantly, demonstrated isolation or non-communication of deep fluids with the biosphere for millions of years. This isolation is the most important characteristic, with the other conditions mainly being those that will enhance the potential of locating and maintaining the isolated zones. Candidate sites will probably be located on the craton in very old Precambrian crystalline rocks, most likely the center of a granitic pluton. The sites will be located in tectonically stable areas with no recent volcanic or seismic activity, and situated away from tectonic features that might become active in the near geologic future

Joint U.S./Russian plutonium disposition study: Nonproliferation issues

International Nuclear Information System (INIS)

Jaeger, C.; Erkkila, B.; Fearey, B.; Ehinger, M.; McAllister, S.; Chitaykin, V.; Ptashny, V.

1996-01-01

In an effort to establish joint activities in the disposition of fissile materials from nuclear materials, the US and Russia agreed to conduct joint work to develop consistent comparisons of various alternatives for the disposition of weapons-grade plutonium. Joint working groups were established for the analysis of alternatives for plutonium management for water reactors, fast reactors, storage, geological formations, immobilization and stabilization of solutions and other forms. In addition cross-cutting working groups were established for economic analysis and nonproliferation (NP). This paper reviews the activities of the NP working group in support of these studies. The NP working group provided integrated support in the area of nuclear NP to the other US/Russian Study teams. It involved both domestic safeguards and security and international safeguards. The analysis of NP involved consideration of the resistance to theft or diversion and resistance to retrieval, extraction or reuse

10 CFR 71.59 - Standards for arrays of fissile material packages.

Science.gov (United States)

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Standards for arrays of fissile material packages. 71.59 Section 71.59 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PACKAGING AND TRANSPORTATION OF RADIOACTIVE.... The value of the CSI may be zero provided that an unlimited number of packages are subcritical, such...

Studies of neutron methods for process control and criticality surveillance of fissile material processing facilities

International Nuclear Information System (INIS)

Zoltowski, T.

1988-01-01

The development of radiochemical processes for fissile material processing and spent fuel handling need new control procedures enabling an improvement of plant throughput. This is strictly related to the implementation of continuous criticality control policy and developing reliable methods for monitoring the reactivity of radiochemical plant operations in presence of the process perturbations. Neutron methods seem to be applicable for fissile material control in some technological facilities. The measurement of epithermal neutron source multiplication with heuristic evaluation of measured data enables surveillance of anomalous reactivity enhancement leading to unsafe states. 80 refs., 47 figs., 33 tabs. (author)

Measurement of inventories with mixed fissile materials

International Nuclear Information System (INIS)

Rinard, P.M.; Krick, M.S.; Kelley, T.; Schneider, C.M.

1997-01-01

An inventory with a large number of diverse items containing mixtures of uranium and plutonium has been measured with two nondestructive assay (NDA) instruments used in four modes. A segmented gamma scanner (SGS) was used to find the number of cans and the positions of the fissile materials by scanning each item in front of a transmissions source; at each position, uranium and plutonium isotopics were measured with the passive gamma rays emitted. A shuffler was then used in both the passive and active modes to measure the masses of the two elements. The measured masses for the inventory items were generally in agreement with the declared values, but anomalies were identified for a small fraction of the inventory

Safeguarding nuclear weapon: Usable materials in Russia

International Nuclear Information System (INIS)

Cochran, T.

1998-01-01

Both the United States and Russia are retaining as strategic reserves more plutonium and HEU for potential reuse as weapons, than is legitimately needed. Both have engaged in discussions and have programs in various stages of development to dispose of excess plutonium and HEU. These fissile material disposition programs will take decades to complete. In the interim there will be, as there is now, hundreds of tons of separated weapon-usable fissile material stored in tens of thousands of transportable canisters, each containing from a few to several tons of kgs of weapon-usable fissile material. This material must be secured against theft and unauthorized use. To have high confidence that the material is secure, one must establish criteria against which the adequacy of the protective systems can be judged. For example, one finds such criteria in US Nuclear Regulatory Commission (USNRC) regulations for the protection of special nuclear materials

LLNL MOX fuel lead assemblies data report for the surplus plutonium disposition environmental impact statement

Energy Technology Data Exchange (ETDEWEB)

O`Connor, D.G.; Fisher, S.E.; Holdaway, R. [and others

1998-08-01

The purpose of this document is to support the US Department of Energy (DOE) Fissile Materials Disposition Program`s preparation of the draft surplus plutonium disposition environmental impact statement. This is one of several responses to data call requests for background information on activities associated with the operation of the lead assembly (LA) mixed-oxide (MOX) fuel fabrication facility. The DOE Office of Fissile Materials Disposition (DOE-MD) has developed a dual-path strategy for disposition of surplus weapons-grade plutonium. One of the paths is to disposition surplus plutonium through irradiation of MOX fuel in commercial nuclear reactors. MOX fuel consists of plutonium and uranium oxides (PuO{sub 2} and UO{sub 2}), typically containing 95% or more UO{sub 2}. DOE-MD requested that the DOE Site Operations Offices nominate DOE sites that meet established minimum requirements that could produce MOX LAs. LLNL has proposed an LA MOX fuel fabrication approach that would be done entirely inside an S and S Category 1 area. This includes receipt and storage of PuO{sub 2} powder, fabrication of MOX fuel pellets, assembly of fuel rods and bundles, and shipping of the packaged fuel to a commercial reactor site. Support activities will take place within a Category 1 area. Building 332 will be used to receive and store the bulk PuO{sub 2} powder, fabricate MOX fuel pellets, and assemble fuel rods. Building 334 will be used to assemble, store, and ship fuel bundles. Only minor modifications would be required of Building 332. Uncontaminated glove boxes would need to be removed, petition walls would need to be removed, and minor modifications to the ventilation system would be required.

Initial data report in response to the surplus plutonium disposition environmental impact statement data call for the UO2 supply. Revision 1

International Nuclear Information System (INIS)

White, V.S.; Cash, J.M.; Michelhaugh, R.D.

1997-11-01

The purpose of this document is to support the US Department of Energy (DOE) Fissile Materials Disposition Program's preparation of the draft Surplus Plutonium Disposition Environmental Impact Statement. This is one of several responses to data calls generated to provide background information on activities associated with the operation of the Mixed-Oxide (MOX) Fuel Fabrication Facility. Urania feed for the MOX Fuel Fabrication Facility may be either natural or depleted. Natural uranium typically contains 0.0057 wt% 234 U, 0.711 wt% 235 U, and the majority as 238 U. The fissile isotope is 235 U, and uranium is considered depleted if the total 235 U content is less than 0.711 wt% as found in nature. The average composition of 235 U in DOE's total depleted urania inventory is 0.20 wt%. The depleted uranium assay range proposed for use in this program is 0.2500--0.2509 wt%. Approximately 30% more natural uranium would be required than depleted uranium based on the importance of maintaining a specific fissile portion in the MOX fuel blend. If the uranium component constitutes a larger quantity of fissile material, less plutonium can be dispositioned on an annual basis. The percentage composition, referred to as assay, of low-enriched uranium necessary for controlled fission in commercial light-water nuclear power reactors is 1.8--5.0 wt% 235 U. This data report provides information on the schedule, acquisition, impacts, and conversion process for using uranium, derived from depleted uranium hexafluoride (UF 6 ), as the diluent for the weapons-grade plutonium declared as surplus. The case analyzed is use of depleted UF 6 in storage at the Portsmouth Gaseous Diffusion Plant in Piketon, Ohio, being transported to a representative UF 6 to uranium dioxide conversion facility (GE Nuclear Energy) for processing, and subsequently transported to the MOX Fuel Fabrication Facility

Harmonisation of criticality assessments of packages for the transport of fissile nuclear fuel cycle materials

International Nuclear Information System (INIS)

Farrington, L.

2004-01-01

The transport of fissile nuclear fuel cycle materials is an international business, and for international shipments the regulations require a package to be certified by each country through or into which the consignment is to be transported. This raises a number of harmonisation issues, which have an important bearing on transport activities. National authorities carry out independent reviews of the criticality safety of packages containing fissile materials but the underlying assumptions used in the calculations can differ, and the outcome is that implementation of the regulations is not uniform. A single design may require multiple criticality analyses to obtain base approval and foreign validations. When several competent authorities are involved, the approval and validation process of package design can often become a time-consuming, expensive and unpredictably lengthy process that can have a significant detrimental effect upon the businesses involved. The characteristics of the fissile nuclear fuel cycle materials transported by the various countries have much in common and so have the designs of the packages to contain them. A greater degree of standardisation should allow criticality safety to be assessed consistently and efficiently with benefits for the nuclear transport industry and the regulatory bodies. (author)

Harmonisation of criticality assessments of packages for the transport of fissile nuclear fuel cycle materials

International Nuclear Information System (INIS)

Farrington, L.

2004-01-01

The transport of fissile nuclear fuel cycle materials is an international business and for international shipments the regulations require a package to be certified by each country through or into which the consignment is to be transported. This raises a number of harmonisation issues, which have an important bearing on transport activities. National authorities carry out independent reviews of criticality safety of packages containing fissile materials but the underlying assumptions used in the calculations can differ, and the outcome is that implementation of the regulations is not uniform. A single design may require multiple criticality analyses to obtain base approval and foreign validations. When several Competent Authorities are involved, the approval and validation process of package design can often become time consuming, expensive and an unpredictably lengthy process that can have a significant detrimental effect upon the businesses involved. The characteristics of the fissile nuclear fuel cycle materials transported by the various countries have much in common and so have the designs of the packages to contain them. A greater degree of standardisation should allow criticality safety to be assessed consistently and efficiently with benefits for the nuclear transport industry and the regulatory bodies

Status of LSDS Development for Isotopic Fissile Assay in Used Fuel

International Nuclear Information System (INIS)

Lee, Y.D.; Ahn, S.; Kim, H.-D.; Song, K.C.; Park, C.J.

2015-01-01

Because of the large amount accumulation of spent fuel, a research to solve the spent fuel problem is actively performed in Korea. One option is to develop the SFR linked with the pyro process to reuse the existing fissile materials in spent fuel. Therefore, an accurate isotopic fissile content assay becomes a key factor in the reuse of fissile material for safety and safeguards purpose. There are several commercial non-destructive technologies for nuclear material assay. However, technology for direct isotopic fissile content assay in spent fuel is not developed yet. Internationally, a verification of special nuclear material in spent fuel, mainly U-235, Pu239, Pu241, is very important for the safeguards objective. These fissile materials can be misused for nuclear weapon purpose, not for peaceful use. As a future nuclear system is developed,, improved safeguards technology must be developed for an approval of fissile materials. A direct measurement of fissile materials is very important to provide a continuous of knowledge on nuclear materials. LSDS (Lead Slowing Down Spectrometer) has an advantage to assay an isotopic fissile content directly, without any help of burnup code and history. LSDS system is under development in KAERI (Korea Atomic Energy Research Institute) for spent fuel and recycled fuel. A linear assay model was setup for U235, Pu239 and Pu241. The dominant individual fission characteristic is appeared between 0.1 eV and 1 keV range. An electron linear accelerator for compact and low cost is under development to produce high source neutron effectively and efficiently. The LSDS is also applicable for optimum design of spent fuel storage and management. The advanced fissile assay technology will contribute to increase the transparency and credibility internationally on a reuse of fissile materials in future nuclear energy system development. (author)

General principles of the nuclear criticality safety for handling, processing and transportation fissile materials in the USSR

International Nuclear Information System (INIS)

Vnukov, V.S.; Rjazanov, B.G.; Sviridov, V.I.; Frolov, V.V.; Zubkov, Y.N.

1991-01-01

The paper describes the general principles of nuclear criticality safety for handling, processing, transportation and fissile materials storing. Measures to limit the consequences of critical accidents are discussed for the fuel processing plants and fissile materials storage. The system of scientific and technical measures on nuclear criticality safety as well as the system of control and state supervision based on the rules, limits and requirements are described. The criticality safety aspects for various stages of handling nuclear materials are considered. The paper gives descriptions of the methods and approaches for critical risk assessments for the processing facilities, plants and storages. (Author)

Proceedings of the workshop on a comparative analysis of approaches to the protection of fissile materials, Stanford University, July 28-30, 1997

International Nuclear Information System (INIS)

Goodby, J.E.; Lehman, R. III; Potter, W.C.

1998-01-01

Events in recent years have caused heightened concern about the security of weapons-usable nuclear material. The possibility of illicit trafficking in, or seizure of, such material, leading to nuclear terrorism, is a worry for all states and their citizens. And given the relatively small quantities required, material obtained in one part of the world could be made into a weapon in another and threaten lives in a third. It is truly a global problem. Since the beginning of the nuclear era, the physical protection of fissile material has been a responsibility of the individual states possessing the material. These states have different organizational approaches for providing physical protection; and while cognizant of recommended general standards, they tend to follow their own practices, shaped by custom, costs, and threat perception. Moreover, the existence of military as well as civil programs in some states adds another dimension to the physical protection issue. Because physical protection is a sovereign matter and not part of an international regime (except for transit of civil material across borders), there has been less attention in much of the world community to the issues of physical protection than to the other elements of nuclear safeguards and controls. (An important exception to this situation is the effort being made to assist the states of the former Soviet Union in the disposition of their weapons-usable nuclear materials.) The lack of a general dialog about a problem of growing concern motivated us to hold a three-day workshop at Stanford University to develop a better understanding of some of the important underlying questions and issues, and to undertake a comparative examination of states' approaches to physical protection. We were pleased to have knowledgeable participants from a number of the countries and regions where physical protection of fissile materials is, or will become, a day-to-day matter. The results of the workshop are reported in

Perspectives on nuclear material safety management methods at DOE sites

International Nuclear Information System (INIS)

Hyder, M.L.

1997-01-01

The management of nuclear materials, and fissile materials in particular, at the USDOE facilities is undergoing significant changes. These result in large part from decreasing requirements for these materials in the US weapons program. Not only is new production no longer required, but returns must be handled and safely stored. Eventually surplus fissile material will be used for power production, or else put into a form suitable for long term disposition. In the meanwhile concentrates must be stored with protection against releases of radioactive material to the environment, and also against theft or deliberate dispersion. In addition, cleaning up large volumes of materials contaminated with fissile isotopes will be a major activity, and there will also be some quantity of spent fuel containing enriched uranium that cannot readily be processed. All these activities pose safety problems, some of which are addressed here

Alternative technical summary report for direct disposition in deep boreholes: Direct disposal of plutonium metal/plutonium dioxide in compound canisters, Version 4.0. Fissile Materials Disposition Program

Energy Technology Data Exchange (ETDEWEB)

Wijesinghe, A.M.

1996-08-23

This report summarizes and compares the Immobilized and Direct Beep Borehole Disposition Alternatives. The important design concepts, facility features and operational procedures are briefly described, and a discussion of the issues that affect the evaluation of each alternative against the programmatic assessment criteria that have been established for selecting the preferred alternatives for plutonium disposition.

Self shielding in cylindrical fissile sources in the APNea system

International Nuclear Information System (INIS)

Hensley, D.

1997-01-01

In order for a source of fissile material to be useful as a calibration instrument, it is necessary to know not only how much fissile material is in the source but also what the effective fissile content is. Because uranium and plutonium absorb thermal neutrons so Efficiently, material in the center of a sample is shielded from the external thermal flux by the surface layers of the material. Differential dieaway measurements in the APNea System of five different sets of cylindrical fissile sources show the various self shielding effects that are routinely encountered. A method for calculating the self shielding effect is presented and its predictions are compared with the experimental results

Regulatory issues for deep borehole plutonium disposition

International Nuclear Information System (INIS)

Halsey, W.G.

1995-03-01

As a result of recent changes throughout the world, a substantial inventory of excess separated plutonium is expected to result from dismantlement of US nuclear weapons. The safe and secure management and eventual disposition of this plutonium, and of a similar inventory in Russia, is a high priority. A variety of options (both interim and permanent) are under consideration to manage this material. The permanent solutions can be categorized into two broad groups: direct disposal and utilization. The deep borehole disposition concept involves placing excess plutonium deep into old stable rock formations with little free water present. Issues of concern include the regulatory, statutory and policy status of such a facility, the availability of sites with desirable characteristics and the technologies required for drilling deep holes, characterizing them, emplacing excess plutonium and sealing the holes. This white paper discusses the regulatory issues. Regulatory issues concerning construction, operation and decommissioning of the surface facility do not appear to be controversial, with existing regulations providing adequate coverage. It is in the areas of siting, licensing and long term environmental protection that current regulations may be inappropriate. This is because many current regulations are by intent or by default specific to waste forms, facilities or missions significantly different from deep borehole disposition of excess weapons usable fissile material. It is expected that custom regulations can be evolved in the context of this mission

Exploiting Fission Chain Reaction Dynamics to Image Fissile Materials

Science.gov (United States)

Chapman, Peter Henry

Radiation imaging is one potential method to verify nuclear weapons dismantlement. The neutron coded aperture imager (NCAI), jointly developed by Oak Ridge National Laboratory (ORNL) and Sandia National Laboratories (SNL), is capable of imaging sources of fast (e.g., fission spectrum) neutrons using an array of organic scintillators. This work presents a method developed to discriminate between non-multiplying (i.e., non-fissile) neutron sources and multiplying (i.e., fissile) neutron sources using the NCAI. This method exploits the dynamics of fission chain-reactions; it applies time-correlated pulse-height (TCPH) analysis to identify neutrons in fission chain reactions. TCPH analyzes the neutron energy deposited in the organic scintillator vs. the apparent neutron time-of-flight. Energy deposition is estimated from light output, and time-of-flight is estimated from the time between the neutron interaction and the immediately preceding gamma interaction. Neutrons that deposit more energy than can be accounted for by their apparent time-of-flight are identified as fission chain-reaction neutrons, and the image is reconstructed using only these neutron detection events. This analysis was applied to measurements of weapons-grade plutonium (WGPu) metal and 252Cf performed at the Nevada National Security Site (NNSS) Device Assembly Facility (DAF) in July 2015. The results demonstrate it is possible to eliminate the non-fissile 252Cf source from the image while preserving the fissileWGPu source. TCPH analysis was also applied to additional scenes in which theWGPu and 252Cf sources were measured individually. The results of these separate measurements further demonstrate the ability to remove the non-fissile 252Cf source and retain the fissileWGPu source. Simulations performed using MCNPX-PoliMi indicate that in a one hour measurement, solid spheres ofWGPu are retained at a 1sigma level for neutron multiplications M -˜ 3.0 and above, while hollowWGPu spheres are

Determining fissile content of nuclear fuel elements

International Nuclear Information System (INIS)

Arya, S.P.; Grossman, L.N.; Schoenig, F.C.

1980-01-01

This invention relates to the determination of the fissile fuel content of fuel for nuclear reactors. A nondestructive method is described for determining rapidly, accurately and simultaneously the fissile content, enrichment and location of fuel material which may also contain amounts of burnable poison, by detecting the γ-rays emitted from the fuel material due to natural radioactive decay. (U.K.)

Methodology for interpretation of fissile mass flow measurements

International Nuclear Information System (INIS)

March-Leuba, J.; Mattingly, J.K.; Mullens, J.A.

1997-01-01

This paper describes a non-intrusive measurement technique to monitor the mass flow rate of fissile material in gaseous or liquid streams. This fissile mass flow monitoring system determines the fissile mass flow rate by relying on two independent measurements: (1) a time delay along a given length of pipe, which is inversely proportional to the fissile material flow velocity, and (2) an amplitude measurement, which is proportional to the fissile concentration (e.g., grams of 235 U per length of pipe). The development of this flow monitor was first funded by DOE/NE in September 95, and initial experimental demonstration by ORNL was described in the 37th INMM meeting held in July 1996. This methodology was chosen by DOE/NE for implementation in November 1996; it has been implemented in hardware/software and is ready for installation. This paper describes the methodology used to interpret the data measured by the fissile mass flow monitoring system and the models used to simulate the transport of fission fragments from the source location to the detectors

Guide for disposition of radioactive-material sources

International Nuclear Information System (INIS)

Taylor, J.M.; Selby, J.M.

1983-04-01

This guide has been prepared to assist DOE Energy Technology Centers in disposing of radioactive-material sources. The guide describes the steps and requirements necessary to dispose of unwanted sources. The steps include obtaining approvals, source characterization, source disposition, packaging requirements, and shipment preparation. A flow chart is provided in the guide to assist the user in the necessary sequential steps of source disposition

Reactor-Based Plutonium Disposition: Opportunities, Options, and Issues

International Nuclear Information System (INIS)

Greene, S.R.

1999-01-01

The end of the Cold War has created a legacy of surplus fissile materials (plutonium and highly enriched uranium) in the United States (U.S.) and the former Soviet Union. These materials pose a danger to national and international security. During the past few years, the U.S. and Russia have engaged in an ongoing dialog concerning the safe storage and disposition of surplus fissile material stockpiles. In January 1997, the Department of Energy (DOE) announced the U. S. would pursue a dual track approach to rendering approximately 50 metric tons of plutonium inaccessible for use in nuclear weapons. One track involves immobilizing the plutonium by combining it with high-level radioactive waste in glass or ceramic ''logs''. The other method, referred to as reactor-based disposition, converts plutonium into mixed oxide (MOX) fuel for nuclear reactors. The U.S. and Russia are moving ahead rapidly to develop and demonstrate the technology required to implement the MOX option in their respective countries. U.S. MOX fuel research and development activities were started in the 1950s, with irradiation of MOX fuel rods in commercial light water reactors (LWR) from the 1960s--1980s. In all, a few thousand MOX fuel rods were successfully irradiated. Though much of this work was performed with weapons-grade or ''near'' weapons-grade plutonium--and favorable fuel performance was observed--the applicability of this data for licensing and use of weapons-grade MOX fuel manufactured with modern fuel fabrication processes is somewhat limited. The U.S. and Russia are currently engaged in an intensive research, development, and demonstration program to support implementation of the MOX option in our two countries. This paper focuses on work performed in the U.S. and provides a brief summary of joint U.S./Russian work currently underway

Reactor-based plutonium disposition: Opportunities, options, and issues

International Nuclear Information System (INIS)

Greene, S.

2000-01-01

The end of the Cold War has created a legacy of surplus fissile materials (plutonium and highly enriched uranium) in the United States (U.S.) and the former Soviet Union. These materials pose a danger to national and international security. During the past few years, the U.S. and Russia have engaged in an ongoing dialog concerning the safe storage and disposition of surplus fissile material stockpiles. In January 1997, the Department of Energy (DOE) announced the U.S. would pursue a dual track approach to rendering approximately 50 metric tons of plutonium inaccessible for use in nuclear weapons. One track involves immobilizing the plutonium by combining it with high-level radioactive waste in glass or ceramic ''logs''. The other method, referred to as reactor-based disposition, converts plutonium into mixed oxide (MOX) fuel for nuclear reactors. The U.S. and Russia are moving ahead rapidly to develop and demonstrate the technology required to implement the MOX option in their respective countries. U.S. MOX fuel research and development activities were started in the 1950s with irradiation of MOX fuel rods in commercial light water reactors (LWR) from the 1960s-1980s. In all, a few thousand MOX fuel rods were successfully irradiated. Though much of this work was performed with weapons-grade or ''near'' weapons-grade plutonium - and favorable fuel performance was observed - the applicability of this data for licensing and use of weapons-grade MOX fuel manufactured with modem fuel fabrication processes is somewhat limited. The U.S. and Russia are currently engaged in an intensive research, development, and demonstration program to support implementation of the MOX option in our two countries. This paper focuses on work performed in the U.S. and provides a brief summary of joint U.S./Russian work currently underway. (author)

''Cats and Dogs'' disposition at Sandia: Last of the legacy materials

International Nuclear Information System (INIS)

Strong, Warren R.; Jackson, John L.

2000-01-01

Over the past 12 months, Sandia National Laboratories, New Mexico (SNL/NM), has successfully conducted an evaluation of its nuclear material holdings. As a result, approximately 46% of these holdings (36% by mass) have been reclassified as no defined use (NDU). Reclassification as NDU allows Sandia to determine the final disposition of a significant percentage of its legacy nuclear material. Disposition will begin some time in mid CY2000. This reclassification and the proposed disposition of the material has resulted in an extensive coordination effort lead by the Nuclear Materials Management Team (NMMT), which includes the nuclear material owners, the Radioactive Waste/Nuclear Material Disposition Department (7135), and DOE Albuquerque Operations Office. The process of identifying and reclassifying the cats and dogs or miscellaneous lots of nuclear material has also presented a number of important lessons learned for other sites in the DOE complex

Strategy for the future use and disposition of uranium-233: Technical information

International Nuclear Information System (INIS)

Bereolos, P.J.; Forsberg, C.W.; Kocher, D.C.; Krichinsky, A.M.

1998-04-01

This document provides a summary of technical information on the synthetic radioisotope 233 U. It is one of a series of four reports that map out a national strategy for the future use and disposition of 233 U. The technical information on 233 U in this document falls into two main areas. First, material characteristics are presented along with the contrasts of 233 U to the more well known strategic fissile materials, 235 U and plutonium (Pu). Second, information derived from the scientific information, such as safeguards, waste classifications, material form, and packaging, is presented. Throughout, the effects of isotopically diluting 233 U with nonfissile, depleted uranium (DU) are examined

The molten salt reactor option for beneficial use of fissile material from dismantled weapons

International Nuclear Information System (INIS)

Gat, U.; Engel, J.R.

1991-01-01

The Molten Salt Reactor (MSR) option for burning fissile fuel from dismantled weapons is examined and is found very suitable for the beneficial use of this fuel. MSRs can utilize any fissile fuel in continuous operation with no special modifications, as demonstrated in the Molten Salt Reactor Experiment. Thus, MSRs are flexible while maintaining their economy. Furthermore, MSRs require only a minimum of special fuel preparation. They can tolerate denaturing and dilution of their fuel. The size of fuel shipments can be determined to optimize safety and security-all of which supports nonproliferation and resists diversion. In addition, MSRs have inherent safety features that make them acceptable and attractive. They can burn fissile material completely or can convert it to other fuels. MSRs also have the potential for burning the actinides and delivering the waste in an optimal form, thus contributing to the solution of one of the major remaining problems in the deployment of nuclear power

A review of the prospects for fusion breeding of fissile material

International Nuclear Information System (INIS)

Geiger, J.S.; Bartholomew, G.A.

1981-10-01

This report is the result of an eight month study by the AECL Fusion Status Study Group. The objectives of this study were to review the current status of fusion research, to evaluate the neutronic performance of various fusion-breeder systems, and to assess the economic and technological outlook for the fusion breeder as a source of fissile material to support CANDU reactors operating on the thorium fuel cycle

Surplus plutonium disposition draft environmental impact statement. Volume 1, Part A

International Nuclear Information System (INIS)

1998-07-01

On May 22, 1997, DOE published a Notice of Intent (NOI) in the Federal Register (62 Federal Register 28009) announcing its decision to prepare an environmental impact statement (EIS) that would tier from the analysis and decisions reached in connection with the Storage and Disposition of Weapons-Usable Fissile Materials Final Programmatic EIS (Storage and Disposition PEIS). DOE's disposition strategy allows for both the immobilization of surplus plutonium and its use as mixed oxide (MOX) fuel in existing domestic, commercial reactors. The disposition of surplus plutonium would also involve disposal of the immobilized plutonium and MOX fuel (as spent nuclear fuel) in a geologic repository. The Surplus Plutonium Disposition Environmental Impact Statement analyzes alternatives that would use the immobilization approach (for some of the surplus plutonium) and the MOX fuel approach (for some of the surplus plutonium); alternatives that would immobilize all of the surplus plutonium; and the No Action Alternative. The alternatives include three disposition facilities that would be designed so that they could collectively accomplish disposition of up to 50 metric tons (55 tons) of surplus plutonium over their operating lives: (1) the pit disassembly and conversion facility would disassemble pits (a weapons component) and convert the recovered plutonium, as well as plutonium metal from other sources, into plutonium dioxide suitable for disposition; (2) the immobilization facility would include a collocated capability for converting nonpit plutonium materials into plutonium dioxide suitable for immobilization and would be located at either Hanford or SRS. DOE has identified SRS as the preferred site for an immobilization facility; (3) the MOX fuel fabrication facility would fabricate plutonium dioxide into MOX fuel. This volume includes background information; purpose of and need for the proposed action; alternatives for disposition of surplus weapons useable plutonium; and

Storage capacity for fissile material as a function of facility shape (room length-to-width ratio)

International Nuclear Information System (INIS)

Altschuler, S.J.

1975-01-01

The results of a previous study for applying surface density methods to square room of varying size are shown to be conservative for rectangular rooms as well. The surface density required to produce criticality has been calculated as a function of the facility length-to-width ratio for a variety of room widths and unit sizes, shapes, and fissile material compositions. For a length to width ratio greater than or equal to 6, the critical surface density is essentially constant. This allows further economies since more fissile material can be stored at a given subcritical value of k/ sub eff/(0.90) in a rectangular vault of given usable area than in a square one. (U.S.)

Fissile and fertile nuclear material measurements using a new differential die-away self-interrogation technique

International Nuclear Information System (INIS)

Menlove, H.O.; Menlove, S.H.; Tobin, S.J.

2009-01-01

This paper presents a new technique for the measurement of fissile and fertile nuclear materials in spent fuel and plutonium-laden materials such as mixed oxide (MOX) fuel. The technique, called differential die-away self-interrogation, is similar to traditional differential die-away analysis, but it does not require a pulsed neutron generator or pulsed beam accelerator, and it can measure the fertile mass in addition to the fissile mass. The new method uses the spontaneous fission neutrons from 244 Cm in spent fuel and 240 Pu effective neutrons in MOX as the 'pulsed' neutron source, with an average of ∼2.7 neutrons per pulse. The time-correlated neutrons from the spontaneous fission and the subsequent induced fissions are analyzed as a function of time to determine the spontaneous fission rate, the induced fast-neutron fissions, and the induced thermal-neutron fissions. The fissile mass is determined from the induced thermal-neutron fissions that are produced by reflected thermal neutrons that originated from the spontaneous fission reaction. The sensitivity of the fissile mass measurement is enhanced by the use of two measurements, with and without a cadmium liner between the sample and a hydrogenous moderator that surrounds the sample. The fertile mass is determined from the multiplicity analysis of the neutrons detected soon after the initial triggering neutron is detected. The method obtains good sensitivity by the optimal design of two different neutron die-away regions: a short die-away for the neutron detector region and a longer die-away for the sample interrogation region.

Update on Monitoring Technologies for International Safeguards and Fissile Material Verification

International Nuclear Information System (INIS)

Croessmann, C. Dennis; Glidewell, Don D.; Mangan, Dennis L.; Smathers, Douglas C.

1999-01-01

Monitoring technologies are playing an increasingly important part in international safeguards and fissile material verification. The developments reduce the time an inspector must spend at a site while assuring continuity of knowledge. Monitoring technologies' continued development has produced new seal systems and integrated video surveillance advances under consideration for Trilateral Initiative use. This paper will present recent developments for monitoring systems at Embalse, Argentina, VNHEF, Sarov, Russian, and Savannah River Site, Aiken, South Carolina

A 252Cf based nondestructive assay system for fissile material

International Nuclear Information System (INIS)

Menlove, H.O.; Crane, T.W.

1978-01-01

A modulated 252 Cf source assay system 'Shuffler' based on fast-or-thermal-neutron interrogation combined with delayed-neutron counting has been developed for the assay of fissile material. The 252 Cf neutron source is repetitively transferred from the interrogation position to a shielded position while the delayed neutrons are counted in a high efficiency 3 He neutron well-counter. For samples containing plutonium, this well-counter is also used in the passive coincidence mode to assay the effective 240 Pu content. The design of an optimized neutron tailoring assembly for fast-neutron interrogation using a Monte Carlo Neutron Computer Code is described. The Shuffler system has been applied to the assay of fuel pellets, inventory samples, irradiated fuel and plutonium mixed-oxide fuel. The system can assay samples with fissile contents from a few milligrams up to several kilograms using thermal-neutron interrogation for the low mass samples and fast-neutron interrogation for the high mass samples. Samples containing 235 U- 238 U, or 233 U-Th, or UO 2 -PuO 2 fuel mixtures have been assayed with the Shuffler system. (Auth.)

Requirements for the transport of surplus fissile materials in the United States

International Nuclear Information System (INIS)

Wilson, R.K.

1995-01-01

This paper discusses the requirements and issues associated with the transportation of surplus fissile materials in the United States. The paper describes the materials that will be transported, the permissible modes of transport for these materials, and the safety and security requirements for each mode of transport. The paper also identifies transportation issues associated with these requirements, including the differences in requirements corresponding to who owns the material and whether the transport is on-site or off-site. Finally, the paper provides a discussion that suggests that by adopting the spent fuel standard and stored weapon standard proposed by the National Academy of Sciences, the requirements for transportation become straightforward

Method of storing fissile mateiral

International Nuclear Information System (INIS)

Onoshita, Toshio; Ishitobi, Masuhiro

1989-01-01

Upon storing nuclear fissile materials in a storing building, vessels packed with fissile materials are inserted into a containing chamber divided with partition walls comprising neutron absorbers and neutron moderators. Thus, released neutrons permeating the vessel are moderated by the neutron moderators and then absorbed by the neutron absorbers. Accordingly, the neutron absorbing effect by the neutron absorbers is improved, and irradiation of neutrons released from one of vessels to the other of vessels can be suppressed. Accordingly, it is possible to shorten the distance between the vessels in a contained state as much as possible, while securing the critical safety, to improve the containing density during storage. (T.M.)

Surplus plutonium disposition draft environmental impact statement. Volume 1, Part B

International Nuclear Information System (INIS)

1998-07-01

On May 22, 1997, DOE published a Notice of Intent (NOI) in the Federal Register (62 Federal Register 28009) announcing its decision to prepare an environmental impact statement (EIS) that would tier from the analysis and decisions reached in connection with the Storage and Disposition of Weapons-Usable Fissile Materials Final Programmatic EIS (Storage and Disposition PEIS). DOE's disposition strategy allows for both the immobilization of surplus plutonium and its use as mixed oxide (MOX) fuel in existing domestic, commercial reactors. The disposition of surplus plutonium would also involve disposal of the immobilized plutonium and MOX fuel (as spent nuclear fuel) in a geologic repository. The Surplus Plutonium Disposition Environmental Impact Statement analyzes alternatives that would use the immobilization approach (for some of the surplus plutonium) and the MOX fuel approach (for some of the surplus plutonium); alternatives that would immobilize all of the surplus plutonium; and the No Action Alternative. The alternatives include three disposition facilities that would be designed so that they could collectively accomplish disposition of up to 50 metric tons (55 tons) of surplus plutonium over their operating lives: (1) the pit disassembly and conversion facility would disassemble pits (a weapons component) and convert the recovered plutonium, as well as plutonium metal from other sources, into plutonium dioxide suitable for disposition; (2) the immobilization facility would include a collocated capability for converting nonpit plutonium materials into plutonium dioxide suitable for immobilization and would be located at either Hanford or SRS. DOE has identified SRS as the preferred site for an immobilization facility; (3) the MOX fuel fabrication facility would fabricate plutonium dioxide into MOX fuel. This volume has chapters on environmental consequences; environmental regulations, permits, and consultations; a glossary; list of preparers; distribution list

IAEA verification of weapon-origin fissile material in the Russian Federation and the United States

International Nuclear Information System (INIS)

2001-01-01

The Secretary of Energy of the United States, Spencer Abraham, Minister of the Russian Federation on Atomic Energy, Alexander Rumyantsev, and Director General of the International Atomic Energy Agency (IAEA), Mohamed ElBaradei, met in Vienna on 18 September 2001 to review progress on the Trilateral Initiative. The Initiative was launched in 1996 to develop a new IAEA verification system for weapon-origin material designated by the United States and the Russian Federation as released from their defence programmes. The removal of weapon-origin fissile material from the defence programmes of the Russian Federation and the United States is in furtherance of the commitment to disarmament undertaken by the two States pursuant to Article VI of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). IAEA verification under this Initiative is intended to promote international confidence that fissile material made subject by either of the two States to Agency verification remains irreversibly removed from nuclear weapon programmes

Glass material oxidation and dissolution system: Converting miscellaneous fissile materials to glass

International Nuclear Information System (INIS)

Forsberg, C.W.; Ferrada, J.J.

1996-01-01

The cold war and the development of nuclear energy have resulted in significant inventories of miscellaneous fissile materials (MFMs). MFMs include (1) plutonium scrap and residue, (2) miscellaneous spent nuclear fuel (SNF), (3) certain hot cell wastes, and (4) many one-of-a-kind materials. Major concerns associated with the long-term management of these materials include: safeguards and nonproliferation issues; health, environment, and safety concerns. waste management requirements; and high storage costs. These issues can be addressed by converting the MFMs to glass for secure, long-term storage or repository disposal; however, conventional glass-making processes require oxide-like feed materials. Converting MFMs to oxide-like materials with subsequent vitrification is a complex and expensive process. A new vitrification process has been invented, the Glass Material Oxidation and Dissolution System (GMODS), which directly converts metals, ceramics, and amorphous solids to glass; oxidizes organics with the residue converted to glass; and converts chlorides to borosilicate glass and a secondary sodium chloride (NaCl) stream. Laboratory work has demonstrated the conversion of cerium (a plutonium surrogate), uranium, Zircaloy, stainless steel, multiple oxides, and other materials to glass. However, significant work is required to develop GMODS further for applications at an industrial scale. If implemented, GMODS will provide a new approach to manage these materials

Device for characterization of fissile materials comprising at least a neutron detector embedded inside a scintillator for gamma radiation detection

International Nuclear Information System (INIS)

Bernard, P.; Dherbey, J.R.; Bosser, R.; Berne, R.

1989-01-01

Fissile materials, for instance in radioactive wastes, are characterized by measurement of prompt and delayed neutrons and gamma radiation from induced fission by a neutron source. Gamma radiation is detected with a scintillation detector associated to a photomultiplier, the scintillation material is at the same time a moderator for thermalization of fast neutrons emitted by the neutron source and also of neutrons from spontaneous fission, (α, n) reactions and neutrons from induced fission in the fissile material. Preferentially the moderator is made of Altustipe (Plexiglas with anthracene as additive) [fr

Development of lead slowing down spectrometer for isotopic fissile assay

International Nuclear Information System (INIS)

Lee, Yong Deok; Park, Chang Je; Ahn, Sang Joon; Kim, Ho Dong

2014-01-01

A lead slowing down spectrometer (LSDS) is under development for analysis of isotopic fissile material contents in pyro-processed material, or spent fuel. Many current commercial fissile assay technologies have a limitation in accurate and direct assay of fissile content. However, LSDS is very sensitive in distinguishing fissile fission signals from each isotope. A neutron spectrum analysis was conducted in the spectrometer and the energy resolution was investigated from 0.1eV to 100keV. The spectrum was well shaped in the slowing down energy. The resolution was enough to obtain each fissile from 0.2eV to 1keV. The detector existence in the lead will disturb the source neutron spectrum. It causes a change in resolution and peak amplitude. The intense source neutron production was designed for ∼E12 n's/sec to overcome spent fuel background. The detection sensitivity of U238 and Th232 fission chamber was investigated. The first and second layer detectors increase detection efficiency. Thorium also has a threshold property to detect the fast fission neutrons from fissile fission. However, the detection of Th232 is about 76% of that of U238. A linear detection model was set up over the slowing down neutron energy to obtain each fissile material content. The isotopic fissile assay using LSDS is applicable for the optimum design of spent fuel storage to maximize burnup credit and quality assurance of the recycled nuclear material for safety and economics. LSDS technology will contribute to the transparency and credibility of pyro-process using spent fuel, as internationally demanded.

Verification of a Fissile Material Cut-off Treaty (FMCT): The Potential Role of the IAEA

International Nuclear Information System (INIS)

Chung, Jin Ho

2016-01-01

The objective of a future verification of a FMCT(Fissile Material Cut-off Treaty) is to deter and detect non-compliance with treaty obligations in a timely and non-discriminatory manner with regard to banning the production of fissile material for nuclear weapons or other nuclear devices. Since the International Atomic Energy Agency (IAEA) has already established the IAEA safeguards as a verification system mainly for Non -Nuclear Weapon States (NNWSs), it is expected that the IAEA's experience and expertise in this field will make a significant contribution to setting up a future treaty's verification regime. This paper is designed to explore the potential role of the IAEA in verifying the future treaty by analyzing verification abilities of the Agency in terms of treaty verification and expected challenges. Furthermore, the concept of multilateral verification that could be facilitated by the IAEA will be examined as a measure of providing a credible assurance of compliance with a future treaty. In this circumstance, it is necessary for the IAEA to be prepared for playing a leading role in FMCT verifications as a form of multilateral verification by taking advantage of its existing verification concepts, methods, and tools. Also, several challenges that the Agency faces today need to be overcome, including dealing with sensitive and proliferative information, attribution of fissile materials, lack of verification experience in military fuel cycle facilities, and different attitude and culture towards verification between NWSs and NNWSs

Verification of a Fissile Material Cut-off Treaty (FMCT): The Potential Role of the IAEA

Energy Technology Data Exchange (ETDEWEB)

Chung, Jin Ho [Korea Institute of Nuclear Nonproliferation and Control, Daejeon (Korea, Republic of)

2016-05-15

The objective of a future verification of a FMCT(Fissile Material Cut-off Treaty) is to deter and detect non-compliance with treaty obligations in a timely and non-discriminatory manner with regard to banning the production of fissile material for nuclear weapons or other nuclear devices. Since the International Atomic Energy Agency (IAEA) has already established the IAEA safeguards as a verification system mainly for Non -Nuclear Weapon States (NNWSs), it is expected that the IAEA's experience and expertise in this field will make a significant contribution to setting up a future treaty's verification regime. This paper is designed to explore the potential role of the IAEA in verifying the future treaty by analyzing verification abilities of the Agency in terms of treaty verification and expected challenges. Furthermore, the concept of multilateral verification that could be facilitated by the IAEA will be examined as a measure of providing a credible assurance of compliance with a future treaty. In this circumstance, it is necessary for the IAEA to be prepared for playing a leading role in FMCT verifications as a form of multilateral verification by taking advantage of its existing verification concepts, methods, and tools. Also, several challenges that the Agency faces today need to be overcome, including dealing with sensitive and proliferative information, attribution of fissile materials, lack of verification experience in military fuel cycle facilities, and different attitude and culture towards verification between NWSs and NNWSs.

Surplus plutonium disposition draft environmental impact statement. Volume 2

International Nuclear Information System (INIS)

1998-07-01

On May 22, 1997, DOE published a Notice of Intent (NOI) in the Federal Register (62 Federal Register 28009) announcing its decision to prepare an environmental impact statement (EIS) that would tier from the analysis and decisions reached in connection with the Storage and Disposition of Weapons-Usable Fissile Materials Final Programmatic EIS (Storage and Disposition PEIS). DOE's disposition strategy allows for both the immobilization of surplus plutonium and its use as mixed oxide (MOX) fuel in existing domestic, commercial reactors. The disposition of surplus plutonium would also involve disposal of the immobilized plutonium and MOX fuel (as spent nuclear fuel) in a geologic repository. The Surplus Plutonium Disposition Environmental Impact Statement analyzes alternatives that would use the immobilization approach (for some of the surplus plutonium) and the MOX fuel approach (for some of the surplus plutonium); alternatives that would immobilize all of the surplus plutonium; and the No Action Alternative. The alternatives include three disposition facilities that would be designed so that they could collectively accomplish disposition of up to 50 metric tons (55 tons) of surplus plutonium over their operating lives: (1) the pit disassembly and conversion facility would disassemble pits (a weapons component) and convert the recovered plutonium, as well as plutonium metal from other sources, into plutonium dioxide suitable for disposition; (2) the immobilization facility would include a collocated capability for converting nonpit plutonium materials into plutonium dioxide suitable for immobilization and would be located at either Hanford or SRS. DOE has identified SRS as the preferred site for an immobilization facility; (3) the MOX fuel fabrication facility would fabricate plutonium dioxide into MOX fuel. Volume 2 contains the appendices to the report and describe the following: Federal Register notices; contractor nondisclosure statement; adjunct melter

Isotopic fissile assay of spent fuel in a lead slowing-down spectrometer system

Energy Technology Data Exchange (ETDEWEB)

Lee, Yong Deok; Jeon, Ju Young [Dept. of Fuel Cycle Technology, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Park, Chang Je [Dept. of Nuclear Engineering, Sejong University, Seoul (Korea, Republic of)

2017-04-15

A lead slowing-down spectrometer (LSDS) system is under development to analyze isotopic fissile content that is applicable to spent fuel and recycled material. The source neutron mechanism for efficient and effective generation was also determined. The source neutron interacts with a lead medium and produces continuous neutron energy, and this energy generates dominant fission at each fissile, below the unresolved resonance region. From the relationship between the induced fissile fission and the fast fission neutron detection, a mathematical assay model for an isotopic fissile material was set up. The assay model can be expanded for all fissile materials. The correction factor for self-shielding was defined in the fuel assay area. The corrected fission signature provides well-defined fission properties with an increase in the fissile content. The assay procedure was also established. The assay energy range is very important to take into account the prominent fission structure of each fissile material. Fission detection occurred according to the change of the Pu239 weight percent (wt%), but the content of U235 and Pu241 was fixed at 1 wt%. The assay result was obtained with 2∼3% uncertainty for Pu239, depending on the amount of Pu239 in the fuel. The results show that LSDS is a very powerful technique to assay the isotopic fissile content in spent fuel and recycled materials for the reuse of fissile materials. Additionally, a LSDS is applicable during the optimum design of spent fuel storage facilities and their management. The isotopic fissile content assay will increase the transparency and credibility of spent fuel storage.

Applications of the ANSI/ANS standard on the storage of fissile materials

International Nuclear Information System (INIS)

Thomas, J.T.

1985-01-01

The American National Standard ''Guide for Nuclear Criticality Safety in the Storage of Fissile Materials,'' ANSI/N16.5-1975 is the subject of this paper. The 'Guide' was reaffirmed in 1982. The technical bases for the conditions and requirements are discussed. Suggestions for applications and several general problems addressed by the Guide are presented. The development of information needed for future extensions of the area of applicability is given

Plutonium stabilization and disposition focus area, FY 1999 and FY 2000 multi-year program plan

International Nuclear Information System (INIS)

1998-03-01

Consistent with the Environmental Management's (EM's) plan titled, ''Accelerating Cleanup: Paths to Closure'', and ongoing efforts within the Executive Branch and Congress, this Multi-Year Program Plan (MYPP) for the Plutonium Focus Area was written to ensure that technical gap projects are effectively managed and measured. The Plutonium Focus Area (PFA) defines and manages technology development programs that contribute to the effective stabilization of nuclear materials and their subsequent safe storage and final disposition. The scope of PFA activities includes the complete spectrum of plutonium materials, special isotopes, and other fissile materials. The PFA enables solutions to site-specific and complex-wide technology issues associated with plutonium remediation, stabilization, and preparation for disposition. The report describes the current technical activities, namely: Plutonium stabilization (9 studies); Highly enriched uranium stabilization (2 studies); Russian collaboration program (2 studies); Packaging and storage technologies (6 studies); and PFA management work package/product line (3 studies). Budget information for FY 1999 and FY 2000 is provided

Plutonium stabilization and disposition focus area, FY 1999 and FY 2000 multi-year program plan

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-03-01

Consistent with the Environmental Management`s (EM`s) plan titled, ``Accelerating Cleanup: Paths to Closure``, and ongoing efforts within the Executive Branch and Congress, this Multi-Year Program Plan (MYPP) for the Plutonium Focus Area was written to ensure that technical gap projects are effectively managed and measured. The Plutonium Focus Area (PFA) defines and manages technology development programs that contribute to the effective stabilization of nuclear materials and their subsequent safe storage and final disposition. The scope of PFA activities includes the complete spectrum of plutonium materials, special isotopes, and other fissile materials. The PFA enables solutions to site-specific and complex-wide technology issues associated with plutonium remediation, stabilization, and preparation for disposition. The report describes the current technical activities, namely: Plutonium stabilization (9 studies); Highly enriched uranium stabilization (2 studies); Russian collaboration program (2 studies); Packaging and storage technologies (6 studies); and PFA management work package/product line (3 studies). Budget information for FY 1999 and FY 2000 is provided.

Global nuclear material flow/control model

International Nuclear Information System (INIS)

Dreicer, J.S.; Rutherford, D.S.; Fasel, P.K.; Riese, J.M.

1997-01-01

This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The nuclear danger can be reduced by a system for global management, protection, control, and accounting as part of an international regime for nuclear materials. The development of an international fissile material management and control regime requires conceptual research supported by an analytical and modeling tool which treats the nuclear fuel cycle as a complete system. The prototype model developed visually represents the fundamental data, information, and capabilities related to the nuclear fuel cycle in a framework supportive of national or an international perspective. This includes an assessment of the global distribution of military and civilian fissile material inventories, a representation of the proliferation pertinent physical processes, facility specific geographic identification, and the capability to estimate resource requirements for the management and control of nuclear material. The model establishes the foundation for evaluating the global production, disposition, and safeguards and security requirements for fissile nuclear material and supports the development of other pertinent algorithmic capabilities necessary to undertake further global nuclear material related studies

Smuggling special nuclear materials

International Nuclear Information System (INIS)

Lazaroiu, Gheorghe

1999-01-01

Ever since the collapse of the former Soviet Union reports have circulated with increasing frequency concerning attempts to smuggle materials from that country's civil and military nuclear programs. Such an increase obviously raises a number of concerns (outlined in the author's introduction), chief among which is the possibility that these materials might eventually fall into the hands of proliferant states or terrorist groups. The following issues are presented: significance of materials being smuggled; sources and smuggling routes; potential customers; international efforts to reduce nuclear smuggling; long-term disposition of fissile materials. (author)

Safety analysis report: packages. Argonne National Laboratory SLSF test train shipping container, P-1 shipment. Fissile material. Final report

International Nuclear Information System (INIS)

Meyer, C.A.

1975-06-01

The package is used to ship an instrumented test fuel bundle (test train) containing fissile material. The package assembly is Argonne National Laboratory (ANL) Model R1010-0032. The shipment is fissile class III. The packaging consists of an outer carbon steel container into which an inner container is placed; the inner container is separated from the outer container by urethane foam cushioning material. The test train is supported in the inner container by a series of transverse supports spaced along the length of the test train. Both the inner and outer containers are closed with bolted covers. The covers do not seal the containers in a leaktight manner. The gross weight of the shipment is about 8350 lb. The unirradiated fissile material content is less than 3 kg of UO 2 of up to 93.2 percent enrichment. This is a Type A quantity (transport group III and less than 3 curies) of radioactive material which does not require shielding, cooling or heating, or neutron absorption or moderation functions in its packaging. The maximum exterior dimensions of the container are 37 ft 11 in. long, 24 1 / 2 in. wide, and 19 3 / 4 in. high

The preliminary design of real-time neutron fissile material monitoring system

International Nuclear Information System (INIS)

Shi Jun; Ren Zhongguo; Zhang Ming; Zhao Zhiping; Chen Qi

2013-01-01

In this paper we present the preliminary design to carry out real-time neutron fissile material monitoring system, The system includes hardware and data acquisition software. For the hardware, it is employed with He3 proportional tubes as neutron detectors, polyethylene as moderator, and, to achieve the remote counting, RM4036 counting modules are connected to the remote computer through the 485 ports. The software with real-time data display and storage, alarm and other functions are developed using Visual Basic 6.0. (authors)

Alternative technical summary report for immobilized disposition in deep boreholes: Immobilized disposal of plutonium in coated ceramic pellets in grout without canisters, Version 4.0. Fissile materials disposition program

International Nuclear Information System (INIS)

Wijesinghe, A.M.

1996-01-01

This paper summarizes and compares the immobilized and direct borehole disposition alternatives previously presented in the alternative technical summary. The important design concepts, facility features and operational procedures are first briefly described. This is followed by a discussion of the issues that affect the evaluation of each alternative against the programmatic assessment criteria that have been established for selecting the preferred alternatives for plutonium disposition

Alternative technical summary report for immobilized disposition in deep boreholes: Immobilized disposal of plutonium in coated ceramic pellets in grout without canisters, Version 4.0. Fissile materials disposition program

Energy Technology Data Exchange (ETDEWEB)

Wijesinghe, A.M.

1996-08-23

This paper summarizes and compares the immobilized and direct borehole disposition alternatives previously presented in the alternative technical summary. The important design concepts, facility features and operational procedures are first briefly described. This is followed by a discussion of the issues that affect the evaluation of each alternative against the programmatic assessment criteria that have been established for selecting the preferred alternatives for plutonium disposition.

Assessing Technical and Programmatic Viability of Nuclear Waste and Material Stream Disposition Plans

International Nuclear Information System (INIS)

R. S. Hill; B. Griebenow

1999-01-01

The U.S. Department of Energy (DOE), Office of Environmental Management (EM) has responsibility for cleanup and disposition of nuclear wastes and excess materials that are a legacy of the nuclear arms race. In fulfilling this responsibility, EM applies a systems engineering approach to identify baseline disposition plans for the wastes and materials (storage, stabilization, treatment, and disposal), assess the path viability, and develop integration opportunities to improve the disposition viability or to combine, eliminate, and/or simplify activities, technologies, and facilities across the DOE Complex, evaluate the baseline and alternatives to make informed decisions, and implement and track selected opportunities. This paper focuses on processes used to assess the disposition path viability - the likelihood that current planning for disposition of nuclear waste and materials can be implemented

Transfer of fissile material through shielding coatings in emergency heating of HTGR coated particles

International Nuclear Information System (INIS)

Gudkov, A.N.; Zhuravkov, S.G.; Koptev, M.A.; Kurepin, A.D.

1990-01-01

The measurement results of leakage dynamics of fissile material from the coated particles within a temperature range of 1200 + 2000 deg. C are given. The methods of carrying out the experiments are briefly described. The relation of the leakage rate of uranium-235 from CP (coated particles) with the pyrocarbonic coatings has been obtained. (author)

Royal Order of 30 March 1981 determining the duties and conditions of operation of the public body responsible for radioactive waste and fissile materials management

International Nuclear Information System (INIS)

1981-01-01

The purpose of this Royal Order is to set up a public body to be responsible for management of the storage of conditioned radioactive waste, waste disposal, its transport as well as that of plutonium-bearing or enriched fissile materials, and plutonium storage. It must become operational as soon as possible, in particular in the perspective of the Eurochemic Company's technical operations ceasing as from 31 December 1981. This body will be named the National Body for Radioactive Waste and Fissile Materials (ONDRAF). As respects plutonium-bearing or enriched fissile materials, ONDRAF will deal with the transport of materials which, in accordance with the IAEA recommendations [INFCIRC/225/Rev. 1], require physical protection measures (NEA) [fr

Fissile materials in solution concentration measured by active neutron interrogation

International Nuclear Information System (INIS)

Romeyer Dherbey, J.; Passard, Ch.; Cloue, J.; Bignan, G.

1993-01-01

The use of the active neutron interrogation to measure the concentration of plutonium contained in flow solutions is particularly interesting for fuel reprocessing plants. Indeed, this method gives a signal which is in a direct relation with the fissile materials concentration. Moreover, it is less sensitive to the gamma dose rate than the other nondestructive methods. Two measure methods have been evolved in CEA. Their principles are given into details in this work. The first one consists to detect fission delayed neutrons induced by a 252 Cf source. In the second one fission prompt neutrons induced by a neutron generator of 14 MeV are detected. (O.M.)

Decree of 4 November 1982 on conditions for notification of possession of special fissile materials and source materials and for keeping accounts thereof

International Nuclear Information System (INIS)

1982-01-01

This Decree lays down a detailed procedure for notification of the possession and accounting of special fissile materials and source materials. The Decree was made in pursuance of Decree No. 185 of 13 February 1964 of the President of the Republic concerning radiation protection and licensing procedures. (NEA) [fr

Fissile mass estimation by pulsed neutron source interrogation

Energy Technology Data Exchange (ETDEWEB)

Israelashvili, I., E-mail: israelashvili@gmail.com [Nuclear Research Center of the Negev, P.O.B 9001, Beer Sheva 84190 (Israel); Dubi, C.; Ettedgui, H.; Ocherashvili, A. [Nuclear Research Center of the Negev, P.O.B 9001, Beer Sheva 84190 (Israel); Pedersen, B. [Nuclear Security Unit, Institute for Transuranium Elements, Joint Research Centre, Via E. Fermi, 2749, 21027 Ispra (Italy); Beck, A. [Nuclear Research Center of the Negev, P.O.B 9001, Beer Sheva 84190 (Israel); Roesgen, E.; Crochmore, J.M. [Nuclear Security Unit, Institute for Transuranium Elements, Joint Research Centre, Via E. Fermi, 2749, 21027 Ispra (Italy); Ridnik, T.; Yaar, I. [Nuclear Research Center of the Negev, P.O.B 9001, Beer Sheva 84190 (Israel)

2015-06-11

Passive methods for detecting correlated neutrons from spontaneous fissions (e.g. multiplicity and SVM) are widely used for fissile mass estimations. These methods can be used for fissile materials that emit a significant amount of fission neutrons (like plutonium). Active interrogation, in which fissions are induced in the tested material by an external continuous source or by a pulsed neutron source, has the potential advantages of fast measurement, alongside independence of the spontaneous fissions of the tested fissile material, thus enabling uranium measurement. Until recently, using the multiplicity method, for uranium mass estimation, was possible only for active interrogation made with continues neutron source. Pulsed active neutron interrogation measurements were analyzed with techniques, e.g. differential die away analysis (DDA), which ignore or implicitly include the multiplicity effect (self-induced fission chains). Recently, both, the multiplicity and the SVM techniques, were theoretically extended for analyzing active fissile mass measurements, made by a pulsed neutron source. In this study the SVM technique for pulsed neutron source is experimentally examined, for the first time. The measurements were conducted at the PUNITA facility of the Joint Research Centre in Ispra, Italy. First promising results, of mass estimation by the SVM technique using a pulsed neutron source, are presented.

Improvements of neutron activation techniques for the determination of fissile material concentrations

International Nuclear Information System (INIS)

Papadopoulos, N.N.

1987-01-01

Certain experimental improvements, as variable sample size and irradiation position, automation and flexibility in radiation detection, broaden the measurable concentration range, increase the possible rate and accuracy of analysis and enlarge the application range of home-made nuclear analyzer for fissile material analysis by delayed fission neutron counting and for short-lived multielement analysis by neutron activation gamma-ray spectrometry. Intercomparisons of results by various methods and laboratories show the need for regular checks of techniques to ensure reliable measurements. (author)

LSDS Development for Isotopic Fissile Content Assay

International Nuclear Information System (INIS)

Lee, Yong Deok; Park, Chang Je; Park, Geun Il; Lee, Jung Won; Song, Kee Chan

2010-01-01

Concerning the sustainable energy supply and green house effect, nuclear energy became the most feasible option to meet the energy demand in Korea. However, the production of the spent nuclear fuel is the inevitable situation. Since the first nuclear power plant started to produce the electricity in Korea, the accumulated amount of spent fuels exceeded 10k tomes recently. The accumulation of the spent fuels is the big issue in the society. Therefore, as an option which strengthens the nuclear proliferation resistance and reduces the amount of spent fuels, sodium fast reactor (SFR) program linked with pyro-processing is under development to re-use the PWR spent fuel and produce the energy. In the process, the produced metallic material involves uranium and TRU (transuranic; neptunium, plutonium, and americium). The uranium-TRU is used to fabricate SFR fuel. The burning the recycled fuel in the reactor is to solve the current spent fuel storage problem and to minimize the actinides accumulation having long half-life. Generally, the spent fuel from PWR has unburned ∼1 % U235, produced ∼0.5 % plutonium from decay chain, ∼3 % fission products, ∼ 0.1 % minor actinides (MA) and uranium remainder. About 1.5 % fissile materials still exist in the spent fuel. Therefore, spent fuel is not only waste but energy resource. The direct and isotopic fissile content assay is the crucial technology for the spent fuel reuse. Additionally, the fissile content analysis will contribute to the optimum storage design and safe spent fuel management. Several nondestructive technologies have been developed for the spent fuel assay; gamma ray measurement, passive and active neutron measurements. Spent fuel emits intense gamma rays and neutrons by (a, n) and spontaneous fission. This intense background has the limitation on the direct analysis of fissile materials. Recently, to analyze the individual fissile content, leadslowing down spectrometer (LSDS) has been being developed in Korea

IAEA technical meeting on fissile material strategies for sustainable nuclear energy

International Nuclear Information System (INIS)

Ganguly, Chaitanyamoy; Koyama, Kazutoshi

2005-01-01

A Technical Meeting (TM) on 'Fissile Material Management Strategies for Sustainable Nuclear Energy' was organized by the International Atomic Energy Agency (IAEA) in Vienna from 12 to 15 September 2005. Prior to the TM, three Working Groups (WG) composed of experts from 10 countries prepared Key Issues papers on: 1) Uranium Demand and Supply through 2050; 2) Back-end Fuel Cycle Options; and 3) Sustainable Nuclear Energy beyond 2050: Cross-cutting Issues. Some 36 papers, including 3 key issue papers, were presented during the TM in 3 different sessions. The present paper summarizes the deliberations of the TM. (author)

A comparative assessment of the economics of plutonium disposition

International Nuclear Information System (INIS)

Williams, K.A.; Miller, J.W.; Reid, R.L.

1997-01-01

The US Department of Energy office of Fissile Materials Disposition (DOE/MD) has been evaluating three technologies for the disposition of approximately 50 metric tons of surplus plutonium from defense-related programs: reactors, immobilization, and deep boreholes. As part of the process supporting an early CY 1997 Record of Decision (ROD), a comprehensive assessment of technical viability, cost, and schedule has been conducted by DOE/MD and its national laboratory contractors. Oak Ridge National Laboratory has managed and coordinated the life-cycle cost (LCC) assessment effort for this program. This paper discusses the economic analysis methodology and the results prior to ROD. A secondary intent of the paper is to discuss major technical and economic issues that impact cost and schedule. To evaluate the economics of these technologies on an equitable basis, a set of cost-estimating guidelines and a common cost-estimating format were utilized by all three technology teams. This paper also includes the major economic analysis assumptions and the comparative constant-dollar and discounted-dollar LCCs

Verification of classified fissile material using unclassified attributes

International Nuclear Information System (INIS)

Nicholas, N.J.; Fearey, B.L.; Puckett, J.M.; Tape, J.W.

1998-01-01

This paper reports on the most recent efforts of US technical experts to explore verification by IAEA of unclassified attributes of classified excess fissile material. Two propositions are discussed: (1) that multiple unclassified attributes could be declared by the host nation and then verified (and reverified) by the IAEA in order to provide confidence in that declaration of a classified (or unclassified) inventory while protecting classified or sensitive information; and (2) that attributes could be measured, remeasured, or monitored to provide continuity of knowledge in a nonintrusive and unclassified manner. They believe attributes should relate to characteristics of excess weapons materials and should be verifiable and authenticatable with methods usable by IAEA inspectors. Further, attributes (along with the methods to measure them) must not reveal any classified information. The approach that the authors have taken is as follows: (1) assume certain attributes of classified excess material, (2) identify passive signatures, (3) determine range of applicable measurement physics, (4) develop a set of criteria to assess and select measurement technologies, (5) select existing instrumentation for proof-of-principle measurements and demonstration, and (6) develop and design information barriers to protect classified information. While the attribute verification concepts and measurements discussed in this paper appear promising, neither the attribute verification approach nor the measurement technologies have been fully developed, tested, and evaluated

Fissile fuel assembly for a sub-moderated nuclear reactor

International Nuclear Information System (INIS)

Millot, J.P.; Dejeux, Pol.; Alibran, Patrice.

1983-01-01

Each of the core assemblies is composed of a prismatic case made of a neutron absorbing material, inside which very long rods containing the fissile material are arranged parallel to the height of the case and according to a regular network in the straight sections of the case. At least one piece in a fertile material exposed to the neutrons emitted by the fissile material of the assembly is arranged on each one of the side faces of the case. The invention applies in particular to sub-moderated reactors, cooled and moderated by pressurized water [fr

In field application of differential Die-Away time technique for detecting gram quantities of fissile materials

Science.gov (United States)

Remetti, Romolo; Gandolfo, Giada; Lepore, Luigi; Cherubini, Nadia

2017-10-01

In the frame of Chemical, Biological, Radiological, and Nuclear defense European activities, the ENEA, the Italian National Agency for New Technologies, Energy and Sustainable Economic Development, is proposing the Neutron Active Interrogation system (NAI), a device designed to find transuranic-based Radioactive Dispersal Devices hidden inside suspected packages. It is based on Differential Die-Away time Analysis, an active neutron technique targeted in revealing the presence of fissile material through detection of induced fission neutrons. Several Monte Carlo simulations, carried out by MCNPX code, and the development of ad-hoc design methods, have led to the realization of a first prototype based on a 14 MeV d-t neutron generator coupled with a tailored moderating structure, and an array of helium-3 neutron detectors. The complete system is characterized by easy transportability, light weight, and real-time response. First results have shown device's capability to detect gram quantities of fissile materials.

Quantitative Fissile Assay In Used Fuel Using LSDS System

Science.gov (United States)

Lee, YongDeok; Jeon, Ju Young; Park, Chang-Je

2017-09-01

A quantitative assay of isotopic fissile materials (U235, Pu239, Pu241) was done at Korea Atomic Energy Research Institute (KAERI), using lead slowing down spectrometer (LSDS). The optimum design of LSDS was performed based on economics, easy maintenance and assay effectiveness. LSDS system consists of spectrometer, neutron source, detection and control. LSDS system induces fissile fission and fast neutrons are collected at fission chamber. The detected signal has a direct relation to the mass of existing fissile isotopes. Many current commercial assay technologies have a limitation in direct application on isotopic fissile assay of spent fuel, except chemical analysis. In the designed system, the fissile assay model was setup and the correction factor for self-shield was obtained. The isotopic fissile content assay was performed by changing the content of Pu239. Based on the fuel rod, the isotopic content was consistent with 2% uncertainty for Pu239. By applying the covering (neutron absorber), the effective shielding was obtained and the activation was calculated on the target. From the assay evaluation, LSDS technique is very powerful and direct to analyze the isotopic fissile content. LSDS is applicable for nuclear fuel cycle and spent fuel management for safety and economics. Additionally, an accurate fissile content will contribute to the international transparency and credibility on spent fuel.

Experimental verification of neutron emission method for measuring of fissile material content in spent fuel

International Nuclear Information System (INIS)

Abou-Zaid, A.A.; Pytel, K.

1999-01-01

A non-destructive method of measurement of fissile nuclides content remained in spent fuel from research reactor is presented. The method, called the neutron emission one, is based on counting of fission neutrons emitted from fissile isotopes: 235 U, 239 Pu, 241 Pu. Fissions are induced mainly by neutrons supplied by the external neutron source. Another effects contribute also to the measured neutron population, e. g. source neutrons from penetrating the fuel without being captured and scattered, neutrons (α,n) reactions and from spontaneous fissions of actinides. Complexity of phenomena occurring within the measurement facility required the detailed numerical simulation and experimental studies prior design of ultimate measurement stand. In the previous paper, the results of Monte Carlo simulation on optimisation of measuring stand for neutron emission method were presented. On the basis of those results, the experimental stand for Maria reactor fuel investigation has been designed and manufactured. The present paper, being the continuation of previous one, contains the description of experimental facility and the results of measurements for the fresh fuel (without burnup) and the fuel mock-up (without fissile materials). Although some discrepancies were found between Monte Carlo and experimental results, the main conclusions concerning the optimal geometry of measuring facility have been confirmed. (author)

Advanced research workshop: nuclear materials safety

International Nuclear Information System (INIS)

Jardine, L J; Moshkov, M M.

1999-01-01

The Advanced Research Workshop (ARW) on Nuclear Materials Safety held June 8-10, 1998, in St. Petersburg, Russia, was attended by 27 Russian experts from 14 different Russian organizations, seven European experts from six different organizations, and 14 U.S. experts from seven different organizations. The ARW was conducted at the State Education Center (SEC), a former Minatom nuclear training center in St. Petersburg. Thirty-three technical presentations were made using simultaneous translations. These presentations are reprinted in this volume as a formal ARW Proceedings in the NATO Science Series. The representative technical papers contained here cover nuclear material safety topics on the storage and disposition of excess plutonium and high enriched uranium (HEU) fissile materials, including vitrification, mixed oxide (MOX) fuel fabrication, plutonium ceramics, reprocessing, geologic disposal, transportation, and Russian regulatory processes. This ARW completed discussions by experts of the nuclear materials safety topics that were not covered in the previous, companion ARW on Nuclear Materials Safety held in Amarillo, Texas, in March 1997. These two workshops, when viewed together as a set, have addressed most nuclear material aspects of the storage and disposition operations required for excess HEU and plutonium. As a result, specific experts in nuclear materials safety have been identified, know each other from their participation in t he two ARW interactions, and have developed a partial consensus and dialogue on the most urgent nuclear materials safety topics to be addressed in a formal bilateral program on t he subject. A strong basis now exists for maintaining and developing a continuing dialogue between Russian, European, and U.S. experts in nuclear materials safety that will improve the safety of future nuclear materials operations in all the countries involved because of t he positive synergistic effects of focusing these diverse backgrounds of

Design of LSDS for Isotopic Fissile Assay in Spent Fuel

International Nuclear Information System (INIS)

Lee, Yongdeok; Park, Changje; Kim, Hodong; Song, Kee Chan

2013-01-01

A future nuclear energy system is being developed at Korea Atomic Energy Research Institute (KAERI), the system involves a Sodium Fast Reactor (SFR) linked with the pyro-process. The pyro-process produces a source material to fabricate a SFR fuel rod. Therefore, an isotopic fissile content assay is very important for fuel rod safety and SFR economics. A new technology for an analysis of isotopic fissile content has been proposed using a lead slowing down spectrometer (LSDS). The new technology has several features for a fissile analysis from spent fuel: direct isotopic fissile assay, no background interference, and no requirement from burnup history information. Several calculations were done on the designed spectrometer geometry: detection sensitivity, neutron energy spectrum analysis, neutron fission characteristics, self shielding analysis, and neutron production mechanism. The spectrum was well organized even at low neutron energy and the threshold fission chamber was a proper choice to get prompt fast fission neutrons. The characteristic fission signature was obtained in slowing down neutron energy from each fissile isotope. Another application of LSDS is for an optimum design of the spent fuel storage, maximization of the burnup credit and provision of the burnup code correction factor. Additionally, an isotopic fissile content assay will contribute to an increase in transparency and credibility for the utilization of spent fuel nuclear material, as internationally demanded

DESIGN OF LSDS FOR ISOTOPIC FISSILE ASSAY IN SPENT FUEL

Directory of Open Access Journals (Sweden)

YONGDEOK LEE

2013-12-01

Full Text Available A future nuclear energy system is being developed at Korea Atomic Energy Research Institute (KAERI, the system involves a Sodium Fast Reactor (SFR linked with the pyro-process. The pyro-process produces a source material to fabricate a SFR fuel rod. Therefore, an isotopic fissile content assay is very important for fuel rod safety and SFR economics. A new technology for an analysis of isotopic fissile content has been proposed using a lead slowing down spectrometer (LSDS. The new technology has several features for a fissile analysis from spent fuel: direct isotopic fissile assay, no background interference, and no requirement from burnup history information. Several calculations were done on the designed spectrometer geometry: detection sensitivity, neutron energy spectrum analysis, neutron fission characteristics, self shielding analysis, and neutron production mechanism. The spectrum was well organized even at low neutron energy and the threshold fission chamber was a proper choice to get prompt fast fission neutrons. The characteristic fission signature was obtained in slowing down neutron energy from each fissile isotope. Another application of LSDS is for an optimum design of the spent fuel storage, maximization of the burnup credit and provision of the burnup code correction factor. Additionally, an isotopic fissile content assay will contribute to an increase in transparency and credibility for the utilization of spent fuel nuclear material, as internationally demanded.

Safeguards and security in the face of nonproliferation, material storage and material disposition

International Nuclear Information System (INIS)

Rivers, J.D.; Kohen, M.D.

1996-01-01

Change is everywhere: society, domestic and international business, the US Government. As the world becomes smaller and more interconnected, the task of protecting the US'' most sensitive assets will become more complex. International obligations resulting from treaties and agreements will increasingly impact the Department of Energy (DOE), to include the dismantlement of nuclear weapons, and the safe, secure storage and disposition of special nuclear material that is a product of dismantlement. Two of the most urgent topics facing DOE are the prevention of proliferation of weapons of mass destruction and the future disposition of special nuclear material. This paper discusses how the DOE safeguards and security community is responding to the increasing challenges imposed by these two issues

Prospects for a fissile material cut-off: Achieving a successful NPT review process

International Nuclear Information System (INIS)

Kalinowski, M.

1999-01-01

Finding new and creative ways to overcome the current deadlock in progress in nuclear arms control became the most important question in the past year. For a long time it had been expected that after the conclusion of the Comprehensive Test Ban Treaty, the next step would be to ban production of fissile materials for weapon purposes. Three strategies are proposed for reaching relevant cut-off agreements. First suggests possible fore for achievement of relevant agreements, second is the proposal to begin with international register of inventories and production capabilities for all relevant nuclear materials, and the third one is ti identify equivalent steps obligatory for all the parties involved

Development of a Fissile Materials Irradiation Capability for Advanced Fuel Testing at the MIT Research Reactor

International Nuclear Information System (INIS)

Hu Linwen; Bernard, John A.; Hejzlar, Pavel; Kohse, Gordon

2005-01-01

A fissile materials irradiation capability has been developed at the Massachusetts Institute of Technology (MIT) Research Reactor (MITR) to support nuclear engineering studies in the area of advanced fuels. The focus of the expected research is to investigate the basic properties of advanced nuclear fuels using small aggregates of fissile material. As such, this program is intended to complement the ongoing fuel evaluation programs at test reactors. Candidates for study at the MITR include vibration-packed annular fuel for light water reactors and microparticle fuels for high-temperature gas reactors. Technical considerations that pertain to the design of the MITR facility are enumerated including those specified by 10 CFR 50 concerning the definition of a research reactor and those contained in a separate license amendment that was issued by the U.S. Nuclear Regulatory Commission to MIT for these types of experiments. The former includes limits on the cross-sectional area of the experiment, the physical form of the irradiated material, and the removal of heat. The latter addresses experiment reactivity worth, thermal-hydraulic considerations, avoidance of fission product release, and experiment specific temperature scrams

Safety analysis report: packages 238Pu oxide shipping cask (packaging of fissile and other radioactive materials). Final report

International Nuclear Information System (INIS)

Evans, J.E.; Gates, A.A.

1975-06-01

Plutonium-238 (as PuO 2 powder) is shipped in triple-container stainless steel shipping casks in compliance with ERDA Manual Chapter 0529 (ERDAM 0529), Safety Standards for the Packaging of Fissile and Other Radioactive Materials. (U.S.)

Applications of Monte Carlo technique in the detection of explosives, narcotics and fissile material using neutron sources

International Nuclear Information System (INIS)

Sinha, Amar; Kashyap, Yogesh; Roy, Tushar; Agrawal, Ashish; Sarkar, P.S.; Shukla, Mayank

2009-01-01

The problem of illicit trafficking of explosives, narcotics or fissile materials represents a real challenge to civil security. Neutron based detection systems are being actively explored worldwide as a confirmatory tool for applications in the detection of explosives either hidden inside a vehicle or a cargo container or buried inside soil. The development of a system and its experimental testing is a tedious process and to develop such a system each experimental condition needs to be theoretically simulated. Monte Carlo based methods are used to find an optimized design for such detection system. In order to design such systems, it is necessary to optimize source and detector system for each specific application. The present paper deals with such optimization studies using Monte Carlo technique for tagged neutron based system for explosives and narcotics detection hidden in a cargo and landmine detection using backscatter neutrons. We will also discuss some simulation studies on detection of fissile material and photo-neutron source design for applications on cargo scanning. (author)

A method for managing the storage of fissile materials using criticality indices

International Nuclear Information System (INIS)

Philbin, J.S.; Harms, G.A.

1995-01-01

This paper describes a method for criticality control at fissile material storage facilities. The method involves the use criticiality indices for storage canisters. The logic, methodology, and results for selected canisters are presented. A concept for an interactive computer program using the method is also introduced. The computer program can be used in real time (using precalulated data) to select a Criticality Index (CI) for a container when it is delivered to or packaged at a site. Criticality safety is assured by controlling the sum of the CIs at each storage location below a defined Emit value when containers are moved

A Program to Stabilize Nuclear Materials as Managed by the Plutonium Focus Area

International Nuclear Information System (INIS)

Kenley, B.; Scott, B.; Seidel, B.; Knecht, D.; Southworth, F.; Osborne, K.; Chipman, N.; Creque, T.

1999-01-01

This paper describes the program to stabilize nuclear materials, consistent with the Department of Energy Office of Environmental Management (EM) plan, Accelerating Cleanup: Paths to Closure. The program is managed by the Plutonium Stabilization and Disposition Focus Area, which defines and manages technology development programs to stabilize nuclear materials and assure their subsequent safe storage and final disposition. The scope of the Plutonium Stabilization and Disposition Focus Area (PFA) activities includes non-weapons plutonium materials, special isotopes, and other fissile materials. The PFA provides solutions to site-specific and complex wide technology issues associated with plutonium remediation, stabilization, and preparation for disposition. Our paper describes an important programmatic function of the Department of Energy nuclear materials stabilization program, including the tie-in of policy to research needs and funding for the nuclear materials disposition area. The PFA uses a rigorous systems engineering determination of technology needs and gaps, under the guidance of a Technical Advisory Panel, consisting of complex-wide experts. The Research and Development planning provides an example for other waste areas and should be of interest to Research and Development managers. The materials disposition maps developed by the PFA and described in this paper provide an evaluation of research needs, data gaps and subsequent guidance for the development of technologies for nuclear materials disposition. This paper also addresses the PFA prioritization methodology and its ability to forecast actual time to implementation

The swelling behavior of Ti-stabilized austenitic steels used as structural materials of fissile subassemblies in Phenix

International Nuclear Information System (INIS)

Seran, J.L.; Touron, H.; Maillard, A.; Dubuisson, P.; Hugot, J.P.; Blanchard, P.; Pelletier, M.

1988-06-01

In this paper we analyse the main results obained on pressurized tubes, fissile pins and hexagonal cans, allowing us to characterize the swelling and irradiation creep resistance of Ti-Mod. austenitic steels, used as reference materials for the fast breeder subassembly. After having compared the global behavior of 316Ti and 15-15Ti steels irradiated as fissile pins we examine in more detail the leading variables acting on swelling and irradiation creep resistance of CW 316Ti clads and wrappers. The irradiation creep associated to the principal mechanical stresses (sodium pressure for the wrapper, fission gas pressure for the clad) explain the plastic deformation observed on the wrappers not on the clads. Fissile pins swell more and the scatter of the results is larger than for wrappers or samples. It does not seem possible to invoque flux or primary stress differences to explain this fact. On the opposite the thermal gradient in the thickness of the components appears to be a significant parameter. In fissile pins it gives rise to a swelling gradient observed by electron microscopy that must be taken into account when comparing to the wrapper. As compared to CW 316Ti, CW 15-15Ti is an important improvement since its incubation dose for swelling is far beyond 100 dpa. Further more since it swelling temperature dependence does not seem to be as important as for 316Ti, it should be less sensitive to the effect of thermal gradients

Problems in future negotiations for a treaty on the cut-off of fissile material for nuclear weapons

International Nuclear Information System (INIS)

Schaper, A.

1999-01-01

A treaty to end the production of fissile material for nuclear weapons, the so-called cutoff, is one of the most important next steps on the disarmament agenda.' But meanwhile, the Conference on Disarmament (CD) is deadlocked, and confidence in negotiations taking place in the near future is replaced by bewilderment at the inaction. The underlying conflict of the Comprehensive Test Ban Treaty (CTBT) negotiations can be summarized as nuclear disarmament versus nuclear nonproliferation. The same conflict is now blocking progress with negotiations in the CD on the Fissile Material Cut-off Treaty (FMCT). Nevertheless, the cut-off would be the major policy driver to insert transparency and irreversibility into the disarmament process,' and we need to harness all our efforts to overcome the current difficulties. The CTBT can be regarded as a tool to cap the qualitative nuclear arms race, for example to hinder the future development of qualitatively new nuclear explosives, and an FMCT can be seen as its quantitative counterpart, capping the amount of material available for new nuclear weapons. The complex questions involve political, technical, legal, and economic aspects and constitute a challenge for diplomats and decision makers

Source modulation-correlation measurement for fissile mass flow in gas or liquid fissile streams

International Nuclear Information System (INIS)

Mihalczo, J.T.; March-Leuba, J.A.; Valentine, T.E.; Abston, R.A.; Mattingly, J.K.; Mullens, J.A.

1996-01-01

The method of monitoring fissile mass flow on all three legs of a blending point, where the input is high-enriched uranium (HEU) and low-enriched uranium (LEU) and the product is PEU, can yield the fissile stream velocity and, with calibration, the [sup235]U content. The product of velocity and content integrated over the pipe gives the fissile mass flow in each leg. Also, the ratio of fissile contents in each pipe: HEU/LEU, HEU/PEU, and PEU/LEU, are obtained. By modulating the source on the input HEU pipe differently from that on the output pipe, the HEU gas can be tracked through the blend point. This method can be useful for monitoring flow velocity, fissile content, and fissile mass flow in HEU blenddown of UF[sub 6] if the pressures are high enough to contain some of the induced fission products. This method can also be used to monitor transfer of fissile liquids and other gases and liquids that emit radiation delayed from particle capture. These preliminary experiments with the Oak Ridge apparatus show that the method will work and the modeling is adequate

Portal monitoring for detecting fissile materials and chemical explosives

International Nuclear Information System (INIS)

Albright, D.

1992-01-01

The portal monitoring of pedestrians, packages, equipment, and vehicles entering or leaving areas of high physical security has been common for many years. Many nuclear facilities rely on portal monitoring to prevent the theft or diversion of plutonium and highly enriched uranium. At commercial airports, portals are used to prevent firearms and explosives from being smuggled onto airplanes. An August 1989 Federal Aviation Administration (FAA) regulation requires US airlines to screen luggage on international flights for chemical explosives. This paper reports that portal monitoring is now being introduced into arms-control agreements. Because some of the portal-monitoring equipment that would be useful in verifying arms-control agreements is already widely used as part of the physical security systems at nuclear facilities and commercial airports, the authors review these uses of portal monitoring, as well as its role in verifying the INF treaty. Then the authors survey the major types of portal-monitoring equipment that would be most useful in detecting nuclear warheads or fissile material

The determination by irradiation with a pulsed neutron generator and delayed neutron counting of the amount of fissile material present in a sample; Determination de la quantite de matiere fissile presente dans un echantillon par irradiation au moyen d'une source pulsee de neutrons et comptage des neutrons retardes

Energy Technology Data Exchange (ETDEWEB)

Beliard, L; Janot, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-07-01

A preliminary study was conducted to determine the amount of fissile material present in a sample. The method used consisted in irradiating the sample by means of a pulsed neutron generator and delayed neutron counting. Results show the validity of this method provided some experimental precautions are taken. Checking on the residual proportion of fissile material in leached hulls seems possible. (authors) [French] Ce rapport rend compte d'une etude preliminaire effectuee en vue de determiner la quantite de matiere fissile presente dans un echantillon. La methode utilisee consiste a irradier l'echantillon considere au moyen d'une source puisee de neutrons et a compter les neutrons retardes produits. Les resultats obtenus permettent de conclure a la validite de la methode moyennant certaines precautions. Un controle de la teneur residuelle en matiere fissile des gaines apres traitement semble possible. (auteurs)

Safety analysis report, packages. Drath and Schrader Double Lidded Drum (packaging of fissile and other radioactive materials). Final report

International Nuclear Information System (INIS)

Chalfant, G.G.

1985-07-01

The preceding Safety Analysis Report - Packages qualifies the Drath and Schrader Double Lidded Drum (see appendix E) as a Department of Transportation DOT 7A Type A packaging and/or ''Type A'' foreign made packaging. The allowable contents shall be: in solid form; non-fissile or exempt fissile material (as defined by 49 CFR 173.453); less than 700 pounds (318 kg) in weight; equal to or less than the A 1 or A 2 quantities of radioactive material as appropriate (see 49 CFR 173.435 for tables of A 1 /A 2 values); and hydrogen gas generation in radioactive waste shall be limited to a maximum of 2-1/2% and total gas pressure limited to 5 psig. Package marking shall be as specified in 49 CFR 178.350-3 or as specified by the foreign country of origin

49 CFR 172.441 - FISSILE label.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false FISSILE label. 172.441 Section 172.441... SECURITY PLANS Labeling § 172.441 FISSILE label. (a) Except for size and color, the FISSILE label must be... FISSILE label must be white. [69 FR 3669, Jan. 26, 2004] ...

Life cycle costs for the domestic reactor-based plutonium disposition option

International Nuclear Information System (INIS)

Williams, K.A.

1999-01-01

Projected constant dollar life cycle cost (LCC) estimates are presented for the domestic reactor-based plutonium disposition program being managed by the US Department of Energy Office of Fissile Materials Disposition (DOE/MD). The scope of the LCC estimate includes: design, construction, licensing, operation, and deactivation of a mixed-oxide (MOX) fuel fabrication facility (FFF) that will be used to purify and convert weapons-derived plutonium oxides to MOX fuel pellets and fabricate MOX fuel bundles for use in commercial pressurized-water reactors (PWRs); fuel qualification activities and modification of facilities required for manufacture of lead assemblies that will be used to qualify and license this MOX fuel; and modification, licensing, and operation of commercial PWRs to allow irradiation of a partial core of MOX fuel in combination with low-enriched uranium fuel. The baseline cost elements used for this document are the same as those used for examination of the preferred sites described in the site-specific final environmental impact statement and in the DOE Record of Decision that will follow in late 1999. Cost data are separated by facilities, government accounting categories, contract phases, and expenditures anticipated by the various organizations who will participate in the program over a 20-year period. Total LCCs to DOE/MD are projected at approximately $1.4 billion for a 33-MT plutonium disposition mission

Fissile materials in solution concentration measured by active neutron interrogation; Mesure de concentration en matiere fissile dans les liquides par interrogation neutronique active

Energy Technology Data Exchange (ETDEWEB)

Romeyer Dherbey, J.; Passard, Ch.; Cloue, J.; Bignan, G.

1993-12-31

The use of the active neutron interrogation to measure the concentration of plutonium contained in flow solutions is particularly interesting for fuel reprocessing plants. Indeed, this method gives a signal which is in a direct relation with the fissile materials concentration. Moreover, it is less sensitive to the gamma dose rate than the other nondestructive methods. Two measure methods have been evolved in CEA. Their principles are given into details in this work. The first one consists to detect fission delayed neutrons induced by a {sup 252} Cf source. In the second one fission prompt neutrons induced by a neutron generator of 14 MeV are detected. (O.M.). 6 refs.

Epithermal interrogation of fissile waste

International Nuclear Information System (INIS)

Coop, K.L.; Hollas, C.L.

1996-01-01

Self-shielding of interrogating thermal neutrons in lumps of fissile material can be a major source of error in transuranic waste assay using the widely employed differential dieaway technique. We are developing a new instrument, the combined thermal/epithermal neutron (CTEN) interrogation instrument to detect the occurrence of self- shielding and mitigate its effects. Neutrons are moderated in the graphite walls of the CTEN instrument to provide an interrogating flux of epithermal and thermal neutrons. The induced prompt fission neutrons are detected in proportional counters. We report the results of measurements made with the CTEN instrument, using minimal and highly self-shielding plutonium and uranium sources in 55 gallon drums containing a variety of mock waste matrices. Fissile isotopes and waste forms for which the method is most applicable, and limitations associated with the hydrogen content of the waste package/matrix are described

Device for the determination of concentrations of fissile and/or fertile materials by means of x-ray fluorescence spectrometry

International Nuclear Information System (INIS)

Von Baeckmann, A.; Neuber, J.

1975-01-01

In analyzing fissile and/or fertile materials in the thorium, uranium, neptunium, plutonium, americium and curium group, time and accuracy are significant factors. An automated system for rapidly analyzing these materials includes: sample preparation device in which aliquots of sample are weighed and mixed with known amounts of solution; x-ray fluorescence spectrometer; and, a central control system for controlling the operation and analyzing the data. (auth)

Comparative analysis of non-destructive methods to control fissile materials in large-size containers

Directory of Open Access Journals (Sweden)

Batyaev V.F.

2017-01-01

Full Text Available The analysis of various non-destructive methods to control fissile materials (FM in large-size containers filled with radioactive waste (RAW has been carried out. The difficulty of applying passive gamma-neutron monitoring FM in large containers filled with concreted RAW is shown. Selection of an active non-destructive assay technique depends on the container contents; and in case of a concrete or iron matrix with very low activity and low activity RAW the neutron radiation method appears to be more preferable as compared with the photonuclear one.

IAEA verification of weapon-origin fissile material in the Russian Federation and the United States

International Nuclear Information System (INIS)

2002-01-01

Full text: Russian Federation Minister of Atomic Energy Alexander Rumyantsev, United States Secretary of Energy Spencer Abraham and Director General of the International Atomic Energy Agency (IAEA) Mohamed ElBaradei met in Vienna on 16 September 2002 to review the status of the Trilateral Initiative and agree on its future direction. The parties concluded that the task entrusted to the Trilateral Initiative Working Group in 1996 has been fulfilled. The work completed has demonstrated practical approaches for IAEA verification of weapon-origin fissile material designated as released from defence programmes in classified forms or at certain sensitive facilities. The work included the examination of technical, legal and financial issues associated with such verification. The removal of weapon-origin fissile material from defence programmes of the Russian Federation and the United States is in furtherance of the commitment to disarmament steps undertaken by the two States pursuant to Article VI of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). IAEA verification of the materials declared excess to nuclear weapons programmes and made subject to this Initiative would build international confidence that this material will never again be used in nuclear weapons. Minister Rumyantsev, Secretary Abraham and Director General ElBaradei recognized the value of the groundbreaking work completed over the last six years. Building on the work completed, they directed the technical experts to begin without delay discussions on future possible cooperation within the trilateral format. Minister Rumyantsev, Secretary Abraham and Director General ElBaradei agreed that the Principals would meet again in September 2003 to review progress within the trilateral format. (IAEA)

FMDP reactor alternative summary report: Volume 4, Evolutionary LWR alternative

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-09-01

Significant quantities of weapons-usable fissile materials [primarily plutonium and highly enriched uranium (HEU)] have become surplus to national defense needs both in the United States and Russia. These stocks of fissile materials pose significant dangers to national and international security. The dangers exist not only in the potential proliferation of nuclear weapons but also in the potential for environmental, safety, and health (ES&H) consequences if surplus fissile materials are not properly managed. The purpose of this report is to provide schedule, cost, and technical information that will be used to support the Record of Process (ROD). Following the screening process, DOE/MD via its national laboratories initiated a more detailed analysis activity to further evaluate each of the ten plutonium disposition alternatives that survived the screening process. Three ``Alternative Teams,`` chartered by DOE and comprised of technical experts from across the DOE national laboratory complex, conducted these analyses. One team was chartered for each of the major disposition classes (borehole, immobilization, and reactors). During the last year and a half, the Fissile Materials Disposition Program (FMDP) Reactor Alternative Team (RxAT) has conducted extensive analyses of the cost, schedule, technical maturity, S&S, and other characteristics of reactor-based plutonium disposition. The results of the RxAT`s analyses of the existing LWR, CANDU, and partially complete LWR alternatives are documented in Volumes 1-3 of this report. This document (Volume 4) summarizes the results of these analyses for the ELWR-based plutonium disposition option.

Plutonium Disposition by Immobilization

International Nuclear Information System (INIS)

Gould, T.; DiSabatino, A.; Mitchell, M.

2000-01-01

The ultimate goal of the Department of Energy (DOE) Immobilization Project is to develop, construct, and operate facilities that will immobilize between 17 to 50 tonnes (MT) of U.S. surplus weapons-usable plutonium materials in waste forms that meet the ''spent fuel'' standard and are acceptable for disposal in a geologic repository. Using the ceramic can-in-canister technology selected for immobilization, surplus plutonium materials will be chemically combined into ceramic forms which will be encapsulated within large canisters of high level waste (HLW) glass. Deployment of the immobilization capability should occur by 2008 and be completed within 10 years. In support of this goal, the DOE Office of Fissile Materials Disposition (MD) is conducting development and testing (D and T) activities at four DOE laboratories under the technical leadership of Lawrence Livermore National Laboratory (LLNL). The Savannah River Site has been selected as the site for the planned Plutonium Immobilization Plant (PIP). The D and T effort, now in its third year, will establish the technical bases for the design, construction, and operation of the U. S. capability to immobilize surplus plutonium in a suitable and cost-effective manner. Based on the D and T effort and on the development of a conceptual design of the PIP, automation is expected to play a key role in the design and operation of the Immobilization Plant. Automation and remote handling are needed to achieve required dose reduction and to enhance operational efficiency

Comparative analysis of non-destructive methods to control fissile materials in large-size containers

Science.gov (United States)

Batyaev, V. F.; Sklyarov, S. V.

2017-09-01

The analysis of various non-destructive methods to control fissile materials (FM) in large-size containers filled with radioactive waste (RAW) has been carried out. The difficulty of applying passive gamma-neutron monitoring FM in large containers filled with concreted RAW is shown. Selection of an active non-destructive assay technique depends on the container contents; and in case of a concrete or iron matrix with very low activity and low activity RAW the neutron radiation method appears to be more preferable as compared with the photonuclear one. Note to the reader: the pdf file has been changed on September 22, 2017.

Evolutionary/advanced light water reactor data report

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-02-09

The US DOE Office of Fissile Material Disposition is examining options for placing fissile materials that were produced for fabrication of weapons, and now are deemed to be surplus, into a condition that is substantially irreversible and makes its use in weapons inherently more difficult. The principal fissile materials subject to this disposition activity are plutonium and uranium containing substantial fractions of plutonium-239 uranium-235. The data in this report, prepared as technical input to the fissile material disposition Programmatic Environmental Impact Statement (PEIS) deal only with the disposition of plutonium that contains well over 80% plutonium-239. In fact, the data were developed on the basis of weapon-grade plutonium which contains, typically, 93.6% plutonium-239 and 5.9% plutonium-240 as the principal isotopes. One of the options for disposition of weapon-grade plutonium being considered is the power reactor alternative. Plutonium would be fabricated into mixed oxide (MOX) fuel and fissioned (``burned``) in a reactor to produce electric power. The MOX fuel will contain dioxides of uranium and plutonium with less than 7% weapon-grade plutonium and uranium that has about 0.2% uranium-235. The disposition mission could, for example, be carried out in existing power reactors, of which there are over 100 in the United States. Alternatively, new LWRs could be constructed especially for disposition of plutonium. These would be of the latest US design(s) incorporating numerous design simplifications and safety enhancements. These ``evolutionary`` or ``advanced`` designs would offer not only technological advances, but also flexibility in siting and the option of either government or private (e.g., utility) ownership. The new reactor designs can accommodate somewhat higher plutonium throughputs. This data report deals solely with the ``evolutionary`` LWR alternative.

Evolutionary/advanced light water reactor data report

International Nuclear Information System (INIS)

1996-01-01

The US DOE Office of Fissile Material Disposition is examining options for placing fissile materials that were produced for fabrication of weapons, and now are deemed to be surplus, into a condition that is substantially irreversible and makes its use in weapons inherently more difficult. The principal fissile materials subject to this disposition activity are plutonium and uranium containing substantial fractions of plutonium-239 uranium-235. The data in this report, prepared as technical input to the fissile material disposition Programmatic Environmental Impact Statement (PEIS) deal only with the disposition of plutonium that contains well over 80% plutonium-239. In fact, the data were developed on the basis of weapon-grade plutonium which contains, typically, 93.6% plutonium-239 and 5.9% plutonium-240 as the principal isotopes. One of the options for disposition of weapon-grade plutonium being considered is the power reactor alternative. Plutonium would be fabricated into mixed oxide (MOX) fuel and fissioned (''burned'') in a reactor to produce electric power. The MOX fuel will contain dioxides of uranium and plutonium with less than 7% weapon-grade plutonium and uranium that has about 0.2% uranium-235. The disposition mission could, for example, be carried out in existing power reactors, of which there are over 100 in the United States. Alternatively, new LWRs could be constructed especially for disposition of plutonium. These would be of the latest US design(s) incorporating numerous design simplifications and safety enhancements. These ''evolutionary'' or ''advanced'' designs would offer not only technological advances, but also flexibility in siting and the option of either government or private (e.g., utility) ownership. The new reactor designs can accommodate somewhat higher plutonium throughputs. This data report deals solely with the ''evolutionary'' LWR alternative

FMDP reactor alternative summary report: Volume 4, Evolutionary LWR alternative

International Nuclear Information System (INIS)

1996-09-01

Significant quantities of weapons-usable fissile materials [primarily plutonium and highly enriched uranium (HEU)] have become surplus to national defense needs both in the United States and Russia. These stocks of fissile materials pose significant dangers to national and international security. The dangers exist not only in the potential proliferation of nuclear weapons but also in the potential for environmental, safety, and health (ES ampersand H) consequences if surplus fissile materials are not properly managed. The purpose of this report is to provide schedule, cost, and technical information that will be used to support the Record of Process (ROD). Following the screening process, DOE/MD via its national laboratories initiated a more detailed analysis activity to further evaluate each of the ten plutonium disposition alternatives that survived the screening process. Three ''Alternative Teams,'' chartered by DOE and comprised of technical experts from across the DOE national laboratory complex, conducted these analyses. One team was chartered for each of the major disposition classes (borehole, immobilization, and reactors). During the last year and a half, the Fissile Materials Disposition Program (FMDP) Reactor Alternative Team (RxAT) has conducted extensive analyses of the cost, schedule, technical maturity, S ampersand S, and other characteristics of reactor-based plutonium disposition. The results of the RxAT's analyses of the existing LWR, CANDU, and partially complete LWR alternatives are documented in Volumes 1-3 of this report. This document (Volume 4) summarizes the results of these analyses for the ELWR-based plutonium disposition option

What should ''damaged'' mean in air transport of fissile packages

International Nuclear Information System (INIS)

Luna, R.E.; Falci, F.P.; Blackman, D.

1995-01-01

It is likely that the ongoing process to produce the 1996 version of the IAEA Regulation for the Safe Transport of Radioactive Materials, IAEA Safety Series 6(SS 6) will result in a more stringent package qualification standard for air transport of large quantities of radioactive materials (RAM) than is included in the 1990 version. During the process to define the scope of the new requirements there was extensive discussion of their impact on, and application to, fissile material package qualification criteria. Since fissile materials are shipped in a variety of packagings ranging from exempt to Type B, each packaging of each type must be evaluated for its ability to maintain subcriticality both alone and in arrays and in both damaged and undamaged condition. In the 1990 version of SS 6 ''damaged'' means the condition of a package after it had undergone the ''tests for demonstrating the ability to withstand accident conditions in transport,'' i.e., Type B qualification tests. These tests conditions are typical of severe accidents in surface modes, but are less severe than air mode qualification test environments to be applied to Type C packages. As a result, questions arose about the need for a corresponding change in the 1996 SS 6 to define ''damaged'' to include the Type C test regime for criticality evaluations of fissile packages in air transport

49 CFR 173.477 - Approval of packagings containing greater than 0.1 kg of non-fissile or fissile-excepted uranium...

Science.gov (United States)

2010-10-01

... kg of non-fissile or fissile-excepted uranium hexafluoride. 173.477 Section 173.477 Transportation... non-fissile or fissile-excepted uranium hexafluoride. (a) Each offeror of a package containing more than 0.1 kg of uranium hexafluoride must maintain on file for at least one year after the latest...

Considerations for Disposition of Dry Cask Storage System Materials at End of Storage System Life

International Nuclear Information System (INIS)

Howard, Rob; Van den Akker, Bret

2014-01-01

Dry cask storage systems are deployed at nuclear power plants for used nuclear fuel (UNF) storage when spent fuel pools reach their storage capacity and/or the plants are decommissioned. An important waste and materials disposition consideration arising from the increasing use of these systems is the management of the dry cask storage systems' materials after the UNF proceeds to disposition. Thermal analyses of repository design concepts currently under consideration internationally indicate that waste package sizes for the geologic media under consideration may be significantly smaller than the canisters being used for on-site dry storage by the nuclear utilities. Therefore, at some point along the UNF disposition pathway, there could be a need to repackage fuel assemblies already loaded into the dry storage canisters currently in use. In the United States, there are already over 1650 of these dry storage canisters deployed and approximately 200 canisters per year are being loaded at the current fleet of commercial nuclear power plants. There is about 10 cubic meters of material from each dry storage canister system that will need to be dispositioned. The concrete horizontal storage modules or vertical storage overpacks will need to be reused, re-purposed, recycled, or disposed of in some manner. The empty metal storage canister/cask would also have to be cleaned, and decontaminated for possible reuse or recycling or disposed of, likely as low-level radioactive waste. These material disposition options can have impacts of the overall used fuel management system costs. This paper will identify and explore some of the technical and interface considerations associated with managing the dry cask storage system materials. (authors)

The mass transfer mechanism of fissile material due to fission

International Nuclear Information System (INIS)

Shafrir, N.H.

1975-01-01

A thin 252 Cf source of a mean thickness of an approXimately mono-atomic layer was used as an experimental model for the study of the basic mechanism of the knock-on process taking place in fissile material. Because of the thinness of the source it can be assumed that mainly primary knock-ons are formed. The ejection rate of knock-ons created by direct collisions between fission fragments and source atoms was measured as follows: the ejected atoms were collected in high vacuum on a catcher foil and 252 Cf determined by alpha spectroscopy using a silicon surface barrier detector. The number of 252 Cf ejected from the source in unit time could thus be determined while considering the anisotropy of ejection, geometry and counting efficiency. Taking into account the chemical composition of the source, eta(theor.) = 252 Cf atoms/fission was obtained. This result can be considered in reasonable agreement with experiment confirming that under the experimental conditions described, practically no knock-on cascade is formed. (B.G.)

Russian-U.S. joint program on the safe management of nuclear materials

International Nuclear Information System (INIS)

Witmer, F.E.; Krumpe, P.F.; Carlson, D.D.

1997-12-01

The Russian-US joint program on the safety of nuclear materials was initiated in response to the 1993 Tomsk-7 accident. The bases for this program are the common technical issues confronting the US and Russia in the safe management of excess weapons grade nuclear materials. The US and Russian weapons dismantlement process is producing hundreds of tons of excess Pu and HEU fissile materials. The US is on a two path approach for disposition of excess Pu: (1) use Pu in existing reactors and/or (2) immobilize Pu in glass or ceramics followed by geologic disposal. Russian plans are to fuel reactors with excess Pu. US and Russia are both converting and blending HEU into LEU for use in existing reactors. Fissile nuclear materials storage, handling, processing, and transportation will be occurring in both countries for tens of years. A table provides a history of the major events comprising the Russian-US joint program on the safety of nuclear materials. A paper delineating program efforts was delivered at the SPECTRUM '96 conference. This paper provides an update on program activities since then

Fate Of Fissile Material Bound To Monosodium Titanate During Cooper Catalyzed Peroxide Oxidation Of Tank 48H Waste

International Nuclear Information System (INIS)

Taylor-Pashow, K.

2012-01-01

At the Savannah River Site (SRS), Tank 48H currently holds approximately 240,000 gallons of slurry which contains potassium and cesium tetraphenylborate (TPB). A copper catalyzed peroxide oxidation (CCPO) reaction is currently being examined as a method for destroying the TPB present in Tank 48H. Part of the development of that process includes an examination of the fate of the Tank 48H fissile material which is adsorbed onto monosodium titanate (MST) particles. This report details results from experiments designed to examine the potential degradation of MST during CCPO processing and the subsequent fate of the adsorbed fissile material. Experiments were conducted to simulate the CCPO process on MST solids loaded with sorbates in a simplified Tank 48H simulant. Loaded MST solids were placed into the Tank 48H simplified simulant without TPB, and the experiments were then carried through acid addition (pH adjustment to 11), peroxide addition, holding at temperature (50 C) for one week, and finally NaOH addition to bring the free hydroxide concentration to a target concentration of 1 M. Testing was conducted without TPB to show the maximum possible impact on MST since the competing oxidation of TPB with peroxide was absent. In addition, the Cu catalyst was also omitted, which will maximize the interaction of H 2 O 2 with the MST; however, the results may be non-conservative assuming the Cu-peroxide active intermediate is more reactive than the peroxide radical itself. The study found that both U and Pu desorb from the MST when the peroxide addition begins, although to different extents. Virtually all of the U goes into solution at the beginning of the peroxide addition, whereas Pu reaches a maximum of ∼34% leached during the peroxide addition. Ti from the MST was also found to come into solution during the peroxide addition. Therefore, Ti is present with the fissile in solution. After the peroxide addition is complete, the Pu and Ti are found to precipitate from

User's guide for shipping Type B quantities of radioactive and fissile material, including plutonium, in DOT-6M specification packaging configurations

International Nuclear Information System (INIS)

Kelly, D.L.

1994-09-01

The need for developing a user's guide for shipping Type B quantities of radioactive and fissile material, including plutonium, in a US Department of Transportation Specification 6M (DOT-6M) packaging was identified by the US Department of Energy (DOE)-Headquarters, Transportation Management Division (EM-261) because the DOT-6M packaging is widely used by DOE site contractors and the DOE receives many questions about approved packaging configuration. Currently, EM-261 has the authority to approve new DOT-6M packaging configurations for use by the DOE Operations Offices. This user's guide identifies the DOE-approved DOT-6M packaging configurations and explains how to have new configurations approved by the DOE. The packaging configurations described in this guide are approved by the DOE, and satisfy the applicable DOT requirements and the identified DOE restrictions. These packaging configurations are acceptable for transport of Type B quantities of radioactive and fissile material, including plutonium

Material correlations and models for the irradiation behavior of fissile and fertile material in SNR-300, Mark-II and KNK II, third core

International Nuclear Information System (INIS)

Fenneker; Steinmetz; Toebbe

1986-07-01

The report contains the material correlations and models used in the fuel pin design code IAMBUS for the irradiation behavior of PuO 2 -UO 2 fissile materials and UO 2 fertile materials of the SNR-300 Mark-II reload and the KNK II third core. They are applicable for pellet densities of more than 90 % of the theoretical density. The presented models of the fuel behavior and the applied material correlations have been derived either from single experiments or from the comparison of theoretically predicted integral fuel behavior with the results of fuel pin irradiation experiments. The material correlations have been examined and extended in the frame of the collaborations INTERATOM/KWU and INTERATOM/KfK. French and British results were included, when available from the European fast reactor knowledge exchange [de

A HOLISTIC APPROACH FOR DISPOSITION OF LONG-LIVED RADIOACTIVE MATERIALS

International Nuclear Information System (INIS)

Eriksson, Leif G.; Dials, George E.; Parker, Frank L.

2003-01-01

During the past 45 years, one of the most challenging scientific, engineering, socio-economic, and political tasks and obligations of our time has been to site and develop technical, politically acceptable, solutions to the safe disposition of long-lived radioactive materials (LLRMs). However, at the end of the year 2002, the Waste Isolation Pilot Plant (WIPP) site in the United States of America (USA) hosts the world's only operating LLRM-disposal system, which (1) is based on the LLRM-disposal principles recommended by the National Academy of Sciences (NAS) in 1957, i.e., deep geological disposal in a ''stable'' salt vault/repository, (2) complies with the nation's ''Environmental Radiation Protection Standards for the Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes'', and (3) may receive 175,584 cubic meters (m3) of transuranic radioactive waste (TRUW)a. Pending the scheduled opening of repositories for once-used nuclear fuel (OUNF) in the USA, Sweden, and Finland in the years 2010, 2015, and 2017, respectively, LLRM-disposal solutions remain the missing link in all national LLRM-disposition programs. Furthermore, for a variety of reasons, many nations with nuclear programs have chosen a ''spectator'' stance in terms of enhancing the global nuclear safety culture and the nuclear renaissance, and have either ''slow-tracked'' or deferred their LLRM-disposal programs to allow time for an informed national consensus to evolve based on LLRM-disposition experiences and solutions gained elsewhere. In the meantime, LLRMs will continue to amass in different types and levels of safeguarded storage facilities around the world. In an attempt to contribute to the enhancement of the global nuclear safety culture and the nuclear renaissance, the authors developed the sample holistic approach for synergistic disposition of LLRMs comprising LLRM-disposition components considered either ''proven'' or ''promising'' by the authors. The

Hardware implementation of the ORNL fissile mass flow monitor

International Nuclear Information System (INIS)

McEvers, J.; Sumner, J.; Jones, R.; Ferrell, R.; Martin, C.; Uckan, T.; March-Leuba, J.

1998-01-01

This paper provides an overall description of the implementation of the Oak Ridge National Laboratory (ORNL) Fissile Mass Flow Monitor, which is part of a Blend Down Monitoring System (BDMS) developed by the US Department of Energy (DOE). The Fissile Mass Flow Monitor is designed to measure the mass flow of fissile material through a gaseous or liquid process stream. It consists of a source-modulator assembly, a detector assembly, and a cabinet that houses all control, data acquisition, and supporting electronics equipment. The development of this flow monitor was first funded by DOE/NE in September 95, and an initial demonstration by ORNL was described in previous INMM meetings. This methodology was chosen by DOE/NE for implementation in November 1996, and the hardware/software development is complete. Successful BDMS installation and operation of the complete BDMS has been demonstrated in the Paducah Gaseous Diffusion Plant (PGDP), which is operated by Lockheed Martin Utility Services, Inc. for the US Enrichment Corporation and regulated by the Nuclear Regulatory Commission. Equipment for two BDMS units has been shipped to the Russian Federation

EXAFS and XANES analysis of plutonium and cerium edges from titanate ceramics for fissile materials disposal

International Nuclear Information System (INIS)

Fortner, J. A.; Kropf, A. J.; Bakel, A. J.; Hash, M. C.; Aase, S. B.; Buck, E. C.; Chamerlain, D. B.

1999-01-01

We report x-ray absorption near edge structure (XANES) and extended x-ray absorption fine structure (EXAFS) spectra from the plutonium L III edge and XANES from the cerium L II edge in prototype titanate ceramic hosts. The titanate ceramics studied are based upon the hafnium-pyrochlore and zirconolite mineral structures and will serve as an immobilization host for surplus fissile materials, containing as much as 10 weight % fissile plutonium and 20 weight % (natural or depleted) uranium. Three ceramic formulations were studied: one employed cerium as a ''surrogate'' element, replacing both plutonium and uranium in the ceramic matrix, another formulation contained plutonium in a ''baseline'' ceramic formulation, and a third contained plutonium in a formulation representing a high-impurity plutonium stream. The cerium XANES from the surrogate ceramic clearly indicates a mixed III-IV oxidation state for the cerium. In contrast, XANES analysis of the two plutonium-bearing ceramics shows that the plutonium is present almost entirely as Pu(IV) and occupies the calcium site in the zirconolite and pyrochlore phases. The plutonium EXAFS real-space structure shows a strong second-shell peak, clearly distinct from that of PuO 2 , with remarkably little difference in the plutonium crystal chemistry indicated between the baseline and high-impurity formulations

Safety analysis report: packages. Pu oxide and Am oxide shipping cask (Packaging of fissile and other radioactive materials). Final report

International Nuclear Information System (INIS)

Chalfant, G.G.

1980-05-01

The PuO 2 cask or SP 5320-2 and 3 cask is designed for surface shipment of americium or plutonium. The cask design was physically tested to demonstrate that it met the criteria specified in US ERDA Manual Chapter 0529, and Chapter I, Interstate Commerce Commission. The package has been assessed for transport of up to 357 grams of plutonium (403 grams PuO 2 powder) and up to 176 grams of americium (200 grams AmO 2 powder), having a maximum decay heat of 203 watts. Criticality evaluation alone would allow the shipment as Fissile Class II but the radiation level of the cask, measured at the time of shipment, may exceed 50 mrem/h at the surface and require shipment as Fissile Class III. Sample calculations address only the more restrictive of the two materials, which in most cases is 238 PuO 2

Operational experience in the non-destructive assay of fissile material in General Electric's nuclear fuel fabrication facility

International Nuclear Information System (INIS)

Stewart, J.P.

1976-01-01

Operational experience in the non-destructive assay of fissile material in a variety of forms and containers and incorporation of the assay devices into the accountability measurement system for General Electric's Wilmington Fuel Fabrication Facility measurement control programme is detailed. Description of the purpose and related operational requirements of each non-destructive assay system is also included. In addition, the accountability data acquisition and processing system is described in relation to its interaction with the various non-destructive assay devices and scales used for accountability purposes within the facility. (author)

Reactor physics ideas to design novel reactors with faster fissile growth

International Nuclear Information System (INIS)

Jagannathan, V.; Pal, U.; Karthikeyan, R.; Raj, D.; Srivastava, A.; Khan, S. A.

2007-01-01

There are several types of fission reactors operating in the world adopting generally the open fuel cycle which considers the naturally available fissile nuclide, viz., 2 35U. The accumulated discharged fuel is considered as waste in some countries. However the discharged fuel contains the precious man-made fissile plutonium which would provide the sole means of harnessing the nuclear energy from either depleted uranium or the natural thorium in future. It must be emphasized that the present day power reactors use just about 0.5% of the mined uranium and it would be imprudent to discard the rest of the mass as waste. It is therefore necessary to explore ways and means of exploiting the fertile mass which has the potential of providing the energy without the green house effects for millennia to come. This has to be done by innovating means of large scale fertile to fissile conversion and then using the man-made fissile material for sustenance as well as growth of fission nuclear power. This paper attempts to give a broad picture of the available options and the challenges in realizing the theoretical possibilities

19 CFR 12.104f - Temporary disposition of materials and articles.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 1 2010-04-01 2010-04-01 false Temporary disposition of materials and articles... SECURITY; DEPARTMENT OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Cultural Property § 12.104f Temporary... museum or other cultural or scientific institution in the U.S. if he finds that sufficient safeguards...

Calculation of multiplication factors regarding criticality aiming at the storage of fissile material

International Nuclear Information System (INIS)

Lima Barros, M. de.

1982-04-01

The multiplication factors of several systems with low enrichment, 3,5% and 3,2% in the isotope 235 U, aiming at the storage of fuel of ANGRA-I and ANGRA II, through the method of Monte Carlo, by the computacional code KENO-IV and the library of section of cross Hansen - Roach with 16 groups of energy. The method of Monte Carlo is specially suitable to the calculation of the factor of multiplication, because it is one of the most acurate models of solution and allows the description of complex tridimensional systems. Various tests of sensibility of this method have been done in order to present the most convenient way of working with KENO-IV code. The safety on criticality of stores of fissile material of the 'Fabrica de Elementos Combustiveis ', has been analyzed through the method of Monte Carlo. (Author) [pt

FMDP Reactor Alternative Summary Report: Volume 2 - CANDU heavy water reactor alternative

International Nuclear Information System (INIS)

Greene, S.R.; Spellman, D.J.; Bevard, B.B.

1996-09-01

The Department of Energy Office of Fissile Materials Disposition (DOE/MD) initiated a detailed analysis activity to evaluate each of ten plutonium disposition alternatives that survived an initial screening process. This document, Volume 2 of a four volume report, summarizes the results of these analyses for the CANDU reactor based plutonium disposition alternative

FMDP Reactor Alternative Summary Report: Volume 2 - CANDU heavy water reactor alternative

Energy Technology Data Exchange (ETDEWEB)

Greene, S.R.; Spellman, D.J.; Bevard, B.B. [and others

1996-09-01

The Department of Energy Office of Fissile Materials Disposition (DOE/MD) initiated a detailed analysis activity to evaluate each of ten plutonium disposition alternatives that survived an initial screening process. This document, Volume 2 of a four volume report, summarizes the results of these analyses for the CANDU reactor based plutonium disposition alternative.

Determination of fissile fraction in MOX (mixed U + Pu oxides) fuels for different burnup values

International Nuclear Information System (INIS)

Ozdemir, Levent; Acar, Banu Bulut; Zabunoglu, Okan H.

2011-01-01

When spent Light Water Reactor fuels are processed by the standard Purex method of reprocessing, plutonium (Pu) and uranium (U) in spent fuel are obtained as pure and separate streams. The recovered Pu has a fissile content (consisting of 239 Pu and 241 Pu) greater than 60% typically (although it mainly depends on discharge burnup of spent fuel). The recovered Pu can be recycled as mixed-oxide (MOX) fuel after being blended with a fertile U makeup in a MOX fabrication plant. The burnup that can be obtained from MOX fuel depends on: (1) isotopic composition of Pu, which is closely related to the discharge burnup of spent fuel from which Pu is recovered; (2) the type of fertile U makeup material used (depleted U, natural U, or recovered U); and (3) fraction of makeup material in the mix (blending ratio), which in turn determines the total fissile fraction of MOX. Using the Non-linear Reactivity Model and the code MONTEBURNS, a step-by-step procedure for computing the total fissile content of MOX is introduced. As was intended, the resulting expression is simple enough for quick/hand calculations of total fissile content of MOX required to reach a desired burnup for a given discharge burnup of spent fuel and for a specified fertile U makeup. In any case, due to non-fissile (parasitic) content of recovered Pu, a greater fissile fraction in MOX than that in fresh U is required to obtain the same burnup as can be obtained by the fresh U fuel.

FMDP reactor alternative summary report. Volume 1 - existing LWR alternative

International Nuclear Information System (INIS)

Greene, S.R.; Bevard, B.B.

1996-01-01

Significant quantities of weapons-usable fissile materials [primarily plutonium and highly enriched uranium (HEU)] are becoming surplus to national defense needs in both the United States and Russia. These stocks of fissile materials pose significant dangers to national and international security. The dangers exist not only in the potential proliferation of nuclear weapons but also in the potential for environmental, safety, and health (ES ampersand H) consequences if surplus fissile materials are not properly managed. This document summarizes the results of analysis concerned with existing light water reactor plutonium disposition alternatives

FMDP reactor alternative summary report. Volume 1 - existing LWR alternative

Energy Technology Data Exchange (ETDEWEB)

Greene, S.R.; Bevard, B.B. [and others

1996-10-07

Significant quantities of weapons-usable fissile materials [primarily plutonium and highly enriched uranium (HEU)] are becoming surplus to national defense needs in both the United States and Russia. These stocks of fissile materials pose significant dangers to national and international security. The dangers exist not only in the potential proliferation of nuclear weapons but also in the potential for environmental, safety, and health (ES&H) consequences if surplus fissile materials are not properly managed. This document summarizes the results of analysis concerned with existing light water reactor plutonium disposition alternatives.

A HOLISTIC APPROACH FOR DISPOSITION OF LONG-LIVED RADIOACTIVE MATERIALS

Energy Technology Data Exchange (ETDEWEB)

Eriksson, Leif G.; Dials, George E.; Parker, Frank L.

2003-02-27

During the past 45 years, one of the most challenging scientific, engineering, socio-economic, and political tasks and obligations of our time has been to site and develop technical, politically acceptable, solutions to the safe disposition of long-lived radioactive materials (LLRMs). However, at the end of the year 2002, the Waste Isolation Pilot Plant (WIPP) site in the United States of America (USA) hosts the world's only operating LLRM-disposal system, which (1) is based on the LLRM-disposal principles recommended by the National Academy of Sciences (NAS) in 1957, i.e., deep geological disposal in a ''stable'' salt vault/repository, (2) complies with the nation's ''Environmental Radiation Protection Standards for the Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes'', and (3) may receive 175,584 cubic meters (m3) of transuranic radioactive waste (TRUW)a. Pending the scheduled opening of repositories for once-used nuclear fuel (OUNF) in the USA, Sweden, and Finland in the years 2010, 2015, and 2017, respectively, LLRM-disposal solutions remain the missing link in all national LLRM-disposition programs. Furthermore, for a variety of reasons, many nations with nuclear programs have chosen a ''spectator'' stance in terms of enhancing the global nuclear safety culture and the nuclear renaissance, and have either ''slow-tracked'' or deferred their LLRM-disposal programs to allow time for an informed national consensus to evolve based on LLRM-disposition experiences and solutions gained elsewhere. In the meantime, LLRMs will continue to amass in different types and levels of safeguarded storage facilities around the world. In an attempt to contribute to the enhancement of the global nuclear safety culture and the nuclear renaissance, the authors developed the sample holistic approach for synergistic disposition of LLRMs comprising LLRM-disposition

Integration of health physics, safety and operational processes for management and disposition of recycled uranium wastes at the Fernald Environmental Management Project (FEMP)

International Nuclear Information System (INIS)

Barber, James; Buckley, James

2003-01-01

Fluor Fernald, Inc. (Fluor Fernald), the contractor for the U. S. Department of Energy (DOE) Fernald Environmental Management Project (FEMP), recently submitted a new baseline plan for achieving site closure by the end of calendar year 2006. This plan was submitted at DOE's request, as the FEMP was selected as one of the sites for their accelerated closure initiative. In accordance with the accelerated baseline, the FEMP Waste Management Project (WMP) is actively evaluating innovative processes for the management and disposition of low-level uranium, fissile material, and thorium, all of which have been classified as waste. These activities are being conducted by the Low Level Waste (LLW) and Uranium Waste Disposition (UWD) projects. Alternatives associated with operational processing of individual waste streams, each of which poses potentially unique health physics, industrial hygiene and industrial hazards, are being evaluated for determination of the most cost effective and safe met hod for handling and disposition. Low-level Mixed Waste (LLMW) projects are not addressed in this paper. This paper summarizes historical uranium recycling programs and resultant trace quantity contamination of uranium waste streams with radionuclides, other than uranium. The presentation then describes how waste characterization data is reviewed for radiological and/or chemical hazards and exposure mitigation techniques, in conjunction with proposed operations for handling and disposition. The final part of the presentation consists of an overview of recent operations within LLW and UWD project dispositions, which have been safely completed, and a description of several current operations

Non-destructive assay of fissile materials by detection and multiplicity analysis of spontaneous neutrons

International Nuclear Information System (INIS)

Prosdocimi, A.

1979-01-01

A method for determining the absolute reaction rate of nuclear events giving rise to neutron emission, according to their neutron multiplicity, is proposed. A typical application is the measurement of the (α, n) and spontaneous fission rates in a fissile material sample, particularly of Pu oxide composition. An analysis of random and correlated neutron pulses is carried out on the basis of sequential order without requiring any time interval analysis, then the primary nuclear events are sorted versus their neutron multiplicity. Suitable theoretical relationships enable to derive the absolute (α, n) and SF reaction rates when the physical parameters of the neutron detector and the multiplicity spectrumm of pulses are known. A typical device is described and the results of experiments leading to Pu-239 and Pu-240 assay are given

Spectrum analysis in lead spectrometer for isotopic fissile assay in used fuel

International Nuclear Information System (INIS)

Lee, Y.D.; Park, C.J.; Kim, H.D.; Song, K.C.

2014-01-01

The LSDS system is under development for analyzing isotopic fissile content applicable in a hot cell for the pyro process. The fuel assay area and nuclear material composition were selected for simulation. The source mechanism for efficient neutron generation was also determined. A neutron is produced at the Ta target by hitting it from accelerated electron. The parameters for an electron accelerator are being researched for cost effectiveness, easy maintenance, and compact size. The basic principle of LSDS is that isotopic fissile has its own fission structure below the unresolved resonance region. The source neutron interacts with a lead medium and produces continuous neutron energy, which generates dominant fission at each fissile. Therefore, a spectrum analysis is very important at a lead medium and fuel area for system working. The energy spectrum with respect to slowing down energy and the energy resolution were investigated in lead. A spectrum analysis was done by the existence of surrounding detectors. In particular, high resonance energy was considered. The spectrum was well organized at each slowing down energy and the energy resolution was acceptable to distinguish isotopic fissile fissions. Additionally, LSDS is applicable for the optimum design of spent fuel storage and management.The isotopic fissile content assay will increase the transparency and credibility for spent fuel storage and its re-utilization, as demanded internationally. (author)

Dispositions Supporting Elementary Interns in the Teaching of Reform-Based Science Materials

Science.gov (United States)

Eick, Charles J.; Stewart, Bethany

2010-01-01

Dispositions supporting the teaching of science as structured inquiry by four elementary candidates are presented. Candidates were studied during student teaching based on their positive attitudes toward teaching science with reform-based materials in their methods course. Personal learning histories informed their attitudes, values, and beliefs…

HEU to LEU conversion and blending facility: Metal blending alternative to produce LEU oxide for disposal

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

US DOE is examining options for disposing of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials. The nuclear material is converted to a form more proliferation- resistant than the original form. Blending HEU (highly enriched uranium) with less-enriched uranium to form LEU has been proposed as a disposition option. Five technologies are being assessed for blending HEU. This document provides data to be used in environmental impact analysis for the HEU-LEU disposition option that uses metal blending with an oxide waste product. It is divided into: mission and assumptions, conversion and blending facility descriptions, process descriptions and requirements, resource needs, employment needs, waste and emissions from plant, hazards discussion, and intersite transportation.

HEU to LEU conversion and blending facility: Metal blending alternative to produce LEU oxide for disposal

International Nuclear Information System (INIS)

1995-09-01

US DOE is examining options for disposing of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials. The nuclear material is converted to a form more proliferation- resistant than the original form. Blending HEU (highly enriched uranium) with less-enriched uranium to form LEU has been proposed as a disposition option. Five technologies are being assessed for blending HEU. This document provides data to be used in environmental impact analysis for the HEU-LEU disposition option that uses metal blending with an oxide waste product. It is divided into: mission and assumptions, conversion and blending facility descriptions, process descriptions and requirements, resource needs, employment needs, waste and emissions from plant, hazards discussion, and intersite transportation

FMDP Reactor Alternative Summary Report: Volume 3 - partially complete LWR alternative

International Nuclear Information System (INIS)

Greene, S.R.; Fisher, S.E.; Bevard, B.B.

1996-09-01

The Department of Energy Office of Fissile Materials Disposition (DOE/MD) initiated a detailed analysis activity to evaluate each of ten plutonium disposition alternatives that survived an initial screening process. This document, Volume 3 of a four volume report summarizes the results of these analyses for the partially complete LWR (PCLWR) reactor based plutonium disposition alternative

FMDP Reactor Alternative Summary Report: Volume 3 - partially complete LWR alternative

Energy Technology Data Exchange (ETDEWEB)

Greene, S.R.; Fisher, S.E.; Bevard, B.B. [and others

1996-09-01

The Department of Energy Office of Fissile Materials Disposition (DOE/MD) initiated a detailed analysis activity to evaluate each of ten plutonium disposition alternatives that survived an initial screening process. This document, Volume 3 of a four volume report summarizes the results of these analyses for the partially complete LWR (PCLWR) reactor based plutonium disposition alternative.

Fissile fuel dynamics of breeder/converter reactors

International Nuclear Information System (INIS)

Harms, A.A.

1978-01-01

The long-term fissile fuel dynamics for a hierarchy of fission reactors covering the range from pure-burners to super-breeders is examined. It is found that the breeding gains of the core and blanket can be used to identify several distinct fissile fuel histories and elucidate the importance of fuel cycle characteristics such as the time dependence of the fissile fuel doubling time. On this basis, a self-sufficient fission reactor is introduced and its determining characteristics are identified. (author)

Destructive and non-destructive methods of measuring the quantity and isotopic composition of fissile materials for purposes of national safeguards in the German Democratic Republic

International Nuclear Information System (INIS)

Villun, K.; Gruner, V.; Siebert, Kh.U.; Hoffmann, D.

1979-01-01

The authors give a brief description of the destructive and non-destructive methods of measuring the quantity and isotopic composition of fissile materials used in the nuclear materials accounting and control system of the German Democratic Republic. They cite examples of the use of gamma-spectrometry, X-ray fluorescence analysis, neutron activation, radiochemical techniques, mass-spectrometry and alpha-spectrometry. (author)

Detector and front-end electronics of a fissile mass flow monitoring system

International Nuclear Information System (INIS)

Paulus, M.J.; Uckan, T.; Lenarduzzi, R.; Mullens, J.A.; Castleberry, K.N.; McMillan, D.E.; Mihalczo, J.T.

1997-01-01

A detector and front-end electronics unit with secure data transmission has been designed and implemented for a fissile mass flow monitoring system for fissile mass flow of gases and liquids in a pipe. The unit consists of 4 bismuth germanate (BGO) scintillation detectors, pulse-shaping and counting electronics, local temperature sensors, and on-board local area network nodes which locally acquire data and report to the master computer via a secure network link. The signal gain of the pulse-shaping circuitry and energy windows of the pulse-counting circuitry are periodicially self calibrated and self adjusted in situ using a characteristic line in the fissile material pulse height spectrum as a reference point to compensate for drift such as in the detector gain due to PM tube aging. The temperature- dependent signal amplitude variations due to the intrinsic temperature coefficients of the PM tube gain and BGO scintillation efficiency have been characterized and real-time gain corrections introduced. The detector and electronics design, measured intrinsic performance of the detectors and electronics, and the performance of the detector and electronics within the fissile mass flow monitoring system are described

Irradiation performance of HTGR recycle fissile fuel

International Nuclear Information System (INIS)

Homan, F.J.; Long, E.L. Jr.

1976-08-01

The irradiation performance of candidate HTGR recycle fissile fuel under accelerated testing conditions is reviewed. Failure modes for coated-particle fuels are described, and the performance of candidate recycle fissile fuels is discussed in terms of these failure modes. The bases on which UO 2 and (Th,U)O 2 were rejected as candidate recycle fissile fuels are outlined, along with the bases on which the weak-acid resin (WAR)-derived fissile fuel was selected as the reference recycle kernel. Comparisons are made relative to the irradiation behavior of WAR-derived fuels of varying stoichiometry and conclusions are drawn about the optimum stoichiometry and the range of acceptable values. Plans for future testing in support of specification development, confirmation of the results of accelerated testing by real-time experiments, and improvement in fuel performance and reliability are described

Use of borosilicate-glass raschig rings as a neutron absorber in solutions of fissile material-ANSI/ANS-8.5-1996

International Nuclear Information System (INIS)

Rothe, R.E.; Ketzlach, N.; Finch, D.R.

1996-01-01

American National Standards Institute/American Nuclear Society (ANSI/ANS)-8.5 is one of several standards prepared by the ANS Standards Committee to provide guidance to enhance criticality safety in the handling, storage, and processing of fissionable materials. American National Standard ANSI/ANS-8.5-1996 provides this guidance for one type of boron-loaded glass in one type of geometry (cylindrical rings) for use with fissile solutions. Recorded use of such fixed neutron absorbers for criticality control of fissile solutions dates back to 1958, but some less-well-documented applications were recorded as early as the mid-1940's. The first solid efforts to collect recommendations derived from experience and technology were begun in 1965. Over the next 6 yr additional experiments were performed, and supporting data for the proposed standard were gathered. The first standard on this safety matter was issued in 1971. It was reaffirmed in 1979 with only minor changes and a slight expansion of the coverage. The standard was last revised in 1986

Implementation of the Fissile Mass Flow Monitor Source Verification and Confirmation

Energy Technology Data Exchange (ETDEWEB)

Uckan, Taner [ORNL; March-Leuba, Jose A [ORNL; Powell, Danny H [ORNL; Nelson, Dennis [Sandia National Laboratories (SNL); Radev, Radoslav [Lawrence Livermore National Laboratory (LLNL)

2007-12-01

This report presents the verification procedure for neutron sources installed in U.S. Department of Energy equipment used to measure fissile material flow. The Fissile Mass Flow Monitor (FMFM) equipment determines the {sup 235}U fissile mass flow of UF{sub 6} gas streams by using {sup 252}Cf neutron sources for fission activation of the UF{sub 6} gas and by measuring the fission products in the flow. The {sup 252}Cf sources in each FMFM are typically replaced every 2 to 3 years due to their relatively short half-life ({approx} 2.65 years). During installation of the new FMFM sources, the source identity and neutronic characteristics provided by the manufacturer are verified with the following equipment: (1) a remote-control video television (RCTV) camera monitoring system is used to confirm the source identity, and (2) a neutron detection system (NDS) is used for source-strength confirmation. Use of the RCTV and NDS permits remote monitoring of the source replacement process and eliminates unnecessary radiation exposure. The RCTV, NDS, and the confirmation process are described in detail in this report.

Implementation of the Fissile Mass Flow Monitor Source Verification and Confirmation

International Nuclear Information System (INIS)

Uckan, Taner; March-Leuba, Jose A.; Powell, Danny H.; Nelson, Dennis; Radev, Radoslav

2007-01-01

This report presents the verification procedure for neutron sources installed in U.S. Department of Energy equipment used to measure fissile material flow. The Fissile Mass Flow Monitor (FMFM) equipment determines the 235 U fissile mass flow of UF 6 gas streams by using 252 Cf neutron sources for fission activation of the UF 6 gas and by measuring the fission products in the flow. The 252 Cf sources in each FMFM are typically replaced every 2 to 3 years due to their relatively short half-life (∼ 2.65 years). During installation of the new FMFM sources, the source identity and neutronic characteristics provided by the manufacturer are verified with the following equipment: (1) a remote-control video television (RCTV) camera monitoring system is used to confirm the source identity, and (2) a neutron detection system (NDS) is used for source-strength confirmation. Use of the RCTV and NDS permits remote monitoring of the source replacement process and eliminates unnecessary radiation exposure. The RCTV, NDS, and the confirmation process are described in detail in this report.

Contribution of civilian industry to the management of military fissile materials

International Nuclear Information System (INIS)

Montalembert de, J.A.

2001-01-01

The situation about using of highly enriched uranium (HEU) and weapon grade plutonium (WgPu) for nuclear fuel preparation in U.S.A. and Russian Federation is reviewed. A few remarks were concluded: (1) We stand at the onset of a process that will be lengthy and which is unlikely to stop with the elimination of the 700 t of HEU and 2 x 34.5 t of WgPu concerned so far. If the announced negotiation of the third START treaty concludes favorably, additional tonnages will have to be recycled, particularly on the Russian side whose estimated inventory is larger. (2) The time scales necessitated by the management of these materials should be no surprise. On the one hand, the aim is to reduce an arsenal built up during 45 years of a Cold War. And this return to civilian life of materials of military origin must be achieved in conditions of safety and bilateral or international safeguards (IAEA), which obviously did not constitute the primary concern of the powers who produced them. Besides, insofar as it enlists the services of civilian industry, this return must be carried out with due respect for the equilibrium of markets that are severely mauled today, in other words, in an orderly and progressive manner. (3) Finally, it is important to recognize that without the contribution of the nuclear power industry, the elimination of military fissile materials would raise problems at another scale and would inevitably lead to regrettable waste. It is to be hoped that this will jog the minds of those who urge a rapid end to nuclear energy, when all the evidence demonstrates that the best way to eliminate surplus weapon grade materials is to recycle them in a reactor, in other words, to destroy them or to denature them while generating electricity. (4) The civilian nuclear industry is happy to contribute concretely and significantly to the solution of a problem of surplus nuclear weaponry, while at the same time utilizing technologies successfully developed for power generation

The Molten Salt Reactor option for beneficial use of fissile material from dismantled weapons

International Nuclear Information System (INIS)

Gat, U.; Engel, J.R.; Dodds, H.L.

1991-01-01

The Molten Salt Reactor (MSR) option for burning fissile fuel from dismantled weapons is examined. It is concluded that MSRs are very suitable for beneficial utilization of the dismantled fuel. The MSRs can utilize any fissile fuel in continuous operation with no special modifications, as demonstrated in the Molten Salt Reactor Experiment. Thus MSRs are flexible while maintaining their economy. MSRs further require a minimum of special fuel preparation and can tolerate denaturing and dilution of the fuel. Fuel shipments can be arbitrarily small, all of which supports nonproliferation and averts diversion. MSRs have inherent safety features which make them acceptable and attractive. They can burn a fuel type completely and convert it to other fuels. MSRs also have the potential for burning the actinides and delivering the waste in an optimal form, thus contributing to the solution of one of the major remaining problems for deployment of nuclear power. 19 refs

16 October 1991-Royal Order amending the Royal Order of 30 March 1981 determining the duties and fixing the operating conditions of the Public Body for the Management of Radioactive Waste and Fissile Materials

International Nuclear Information System (INIS)

1991-01-01

The 1991 Royal Order amends and supplements the provisions of the 1981 0rder dealing with the duties and resources of ONDRAF, the National Body for the Management of Radioactive Waste and Fissile Materials. Its duties include, inter alia, treatment and conditioning of waste on behalf of producers without the necessary facilities, training of specialists for such work for the producers with such facilities, transport, storage and disposal of radioactive waste, transport, and storage of certain enriched fissile materials and plutonium-bearing materials. As regards decommissioned nuclear installations, ONDRAF must establish management programmes for the resulting waste and must also decommission a nuclear installation at the operator's request or if he defaults. (NEA)

Nuclear materials facility safety initiative

International Nuclear Information System (INIS)

Peddicord, K.L.; Nelson, P.; Roundhill, M.; Jardine, L.J.; Lazarev, L.; Moshkov, M.; Khromov, V.V.; Kruchkov, E.; Bolyatko, V.; Kazanskij, Yu.; Vorobeva, I.; Lash, T.R.; Newton, D.; Harris, B.

2000-01-01

Safety in any facility in the nuclear fuel cycle is a fundamental goal. However, it is recognized that, for example, should an accident occur in either the U.S. or Russia, the results could seriously delay joint activities to store and disposition weapons fissile materials in both countries. To address this, plans are underway jointly to develop a nuclear materials facility safety initiative. The focus of the initiative would be to share expertise which would lead in improvements in safety and safe practices in the nuclear fuel cycle.The program has two components. The first is a lab-to-lab initiative. The second involves university-to-university collaboration.The lab-to-lab and university-to-university programs will contribute to increased safety in facilities dealing with nuclear materials and related processes. These programs will support important bilateral initiatives, develop the next generation of scientists and engineers which will deal with these challenges, and foster the development of a safety culture

Analyse of the potential of the high temperature reactor with respect to the use of fissile materials

International Nuclear Information System (INIS)

Damian, F.

2001-01-01

The high temperature reactors fuel is made of micro-particles dispersed in a graphite matrix. This configuration makes it possible to reach high burnup, higher than 700 GWj/t. Thanks to the decoupling between the thermal and the neutronic behaviors in the core many types of fuels can be used. These characteristics give to HTR reactor very good capacities to burn fissile materials. This work was done in the frame of the evaluation of HTR capacities to enhance the value of the plutonium stocks. These stocks are currently composed of the irradiated fuels discharged from classical PWR or the dismantling of the nuclear weapons and represent a significant energy potential. These studies concluded that high cycles length can be reached whatever the plutonium quality is (from 50 % to 94 % of fissile plutonium). In addition, it was demonstrated that the moderator temperature coefficient becomes locally positive for highly burn fuel while the core global moderator temperature coefficient remained negative in the operation range of the reactor. A significant share of this work was first devoted to the setting of a modeling of the fuel element but also of the reactor's core with the codes of system SAPHYR. The whole of modeling was validated by reference calculations. This work of code assessment is justified by a preliminary work that showed that the classical calculation scheme used for PWR could not be transposed directly to HTR core. (author)

HEU to LEU conversion and blending facility: Oxide blending alternative to produce LEU oxide for commercial use

International Nuclear Information System (INIS)

1995-09-01

The United States Department of Energy (DOE) is examining options for the disposition of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials. Disposition is a process of use or disposal of material that results in the material being converted to a form that is substantially and inherently more proliferation-resistant than the original form. Examining options for increasing the proliferation resistance of highly enriched uranium (HEU) is part of this effort. This document provides data to be used in the environmental impact analysis for the oxide blending HEU disposition option. This option provides for a yearly HEU throughput of 1 0 metric tons (MT) of uranium metal with an average U235 assay of 50% blended with 165 MT of natural assay triuranium octoxide (U 3 O 8 ) per year to produce 177 MT of 4% U235 assay U 3 O 8 , for LWR fuel. Since HEU exists in a variety of forms and not necessarily in the form to be blended, worst case scenarios for preprocessing prior to blending will be assumed for HEU feed streams

Neutronic studies of fissile and fusile breeding blankets

International Nuclear Information System (INIS)

Taczanowski, S.

1984-08-01

In light of the need of convincing motivation substantiating expensive and inherently applied research (nuclear energy), first a simple comparative study of fissile breeding economics of fusion fission hybrids, spallators and also fast breeder reactors has been carried out. As a result, the necessity of maximization of fissile production (in the first two ones, in fast breeders rather the reprocessing costs should be reduced) has been shown, thus indicating the design strategy (high support ratio) for these systems. In spite of the uncertainty of present projections onto further future and discrepancies in available data even quite conservative assumptions indicate that hybrids and perhaps even earlier - spallators can become economic at realistic uranium price increase and successfully compete against fast breeders. Then on the basis of the concept of the neutron flux shaping aimed at the correlation of the selected cross-sections with the neutron flux, the indications for the maximization of respective reaction rates has been formulated. In turn, these considerations serve as the starting point for the guidelines of breeding blanket nuclear design, which are as follows: 1) The source neutrons must face the multiplying layer (of proper thickness) of possibly low concentration of nuclides attenuating the neutron multiplication (i.e. structure materials, nongaseous coolants). 2) For the most effective trapping of neutrons within the breeding zone (leakage and void streaming reduction) it must contain an efficient moderator (not valid for fissile breeding blankets). 3) All regions of significant slow flux should contain 6 Li in order to reduce parasite neutron captures in there. (orig./HP)

Safety analysis report for packages: packaging of fissile and other radioactive materials. Final report

International Nuclear Information System (INIS)

Chalfant, G.G.

1984-01-01

The 9965, 9966, 9967, and 9968 packages are designed for surface shipment of fissile and other radioactive materials where a high degree of containment (either single or double) is required. Provisions are made to add shielding material to the packaging as required. The package was physically tested to demonstrate that it meets the criteria specified in USDOE Order No. 5480.1, chapter III, dated 5/1/81, which invokes Title 10, Code of Federal Regulations, Part 71 (10 CFR 71), Packing and Transportation of Radioactive Material, and Title 49, Code of Federal Regulations, Part 100-179, Transportation. By restricting the maximum normal operating pressure of the packages to less than 7 kg/cm 2 (gauge) (99 to 54 psig), the packages will comply with Type B(U) regulations of the International Atomic Energy Agency (IAEA) in its Regulations for the Safe Transport of Radioactive Materials, Safety Series No. 6, 1973 Revised Edition, and may be used for export and import shipments. These packages have been assessed for transport of up to 14.5 kilograms of uranium, excluding uranium-233, or 4.4 kilograms of plutonium metal, oxides, or scrap having a maximum radioactive decay energy of 30 watts. Specific maximum package contents are given. This quantity and the configuration of uranium or plutonium metal cannot be made critical by any combination of hydrogeneous reflection and moderation regardless of the condition of the package. For a uranium-233 shipment, a separate criticality evaluation for the specific package is required

Current status and recommended future studies of underground supercriticality of fissile material

International Nuclear Information System (INIS)

Bowman, C.D.

1996-06-01

More than a year has passed since we released our original report pointing out the possibility of natural or induced rearrangement of fissile material underground into a critical mass, the possibility of positive feedback in underground configurations, the confinement of the rock to produce significant yield, and the possibility of venting or explosion. The nuclear weapons and repository storage groups at both Los Alamos and Livermore have been critical of our work while others have defended our calculations on wet and dry criticality. The conditions we identified for positive and negative feedback are no longer contested. The role of confinement of the rock in enhancing the yield from the explosion is still unsettled, and that is addressed later in this paper. The likelihood of confinement, venting, or explosive dispersion also remains unsettled and that is addressed here as well. Some critics of our work have tried to show that the probability of reconfiguration by natural processes is very small. They argue further that emplacement can be done in such a way as to make the probability even smaller. Of course these additional efforts will raise the cost of waste emplacement and the question arises as to how much is enough. The answer to this question seems to not be an easy one

Quantification of Fissile Materials by Photon Activation Method in a Highly Shielded Enclosure

International Nuclear Information System (INIS)

Dighe, P.M.; Pithawa, C.K.; Goswami, A.; Dixit, K.P.; Mittal, K.C.; Sunil, C.; Sarkar, P.K.; Mukhopadhyay, P.K.; Patil, R.K.; Srivastava, G.P.; Ganesan, S.; Venugopal, V.

2010-01-01

For active and non-destructive quantitative identification of heavily shielded fissile materials, photo fission is one of the most often used techniques. High energy photon beams can be conveniently generated with the help of electron LINACs. 10MeV energy electron LINACs are extensively used for various industrial applications such as food irradiation, X-ray radiography, etc. The radiological safety consideration favours the use of electron beam of upto 10 MeV energy. The photonuclear data available on 10 MeV end point energy is very scarce. The present paper gives the results of our initial experiments carried out using natural uranium samples at 10 MeV LINAC facility. Water cooled tantalum target converter was used to produce intense Bremsstrahlung to induce photofission in the samples. Neutron detection system consists of six numbers of high sensitivity Helium-3 proportional counters and gamma detection system consists of two numbers of 76 mm diameter BGO scintillators. Delayed neutron and delayed gamma radiations were measured and analyzed. The mass to count rate relationship has been established for both delayed neutron and gamma radiations. Delayed gamma decay constants of natural uranium have been derived for the 10 MeV end point energy. (author)

Potential for fissile breeding with the fusion-fission hybrid reactor

International Nuclear Information System (INIS)

Bender, D.J.; Lee, J.D.

1976-01-01

The general features of the mirror reactor design are discussed. Details of the blanket-coil geometry are shown. The inside face of the blanket segments are divided into individual pressure vessels. These submodules contain fissile breeding material located directly behind the first wall, a fusile breeding material behind the fertile breeder, and then coolant inlet and outlet plena. Two blankets are examined and compared in this study. One contains natural uranium plus 7 wt. percent Mo, the second contains thorium metal. The performance of these blankets is discussed

Electric breeding of fissile materials with low Q, non-mainline fusion drivers

International Nuclear Information System (INIS)

Benford, J.; Bailey, V.; Oliver, D.; DiCapua, M.; Cooper, R.; Lopez, O.; Lindsey, H.

1977-10-01

The application of two novel fusion reactor concepts to the production of fissile fuel for existing and planned fission reactors has been shown to be technically feasible and potentially economically competitive. The performance required of fusion based breeders has been derived in terms of the fusion gain, blanket neutron and energy multiplication, and the performance and economic parameters of the fission reactors. Electron beam heated, linear solenoid confined plasmas were one concept which showed the most promise. A shock heated, wall confined reactor also appeared attractive for breeding

Fissile Material Disposition Program: Deep Borehole Disposal Facility PEIS data input report for direct disposal. Direct disposal of plutonium metal/plutonium dioxide in compound metal canisters. Version 3.0

Energy Technology Data Exchange (ETDEWEB)

Wijesinghe, A.M.; Shaffer, R.J.

1996-01-15

The US Department of Energy (DOE) is examining options for disposing of excess weapons-usable nuclear materials [principally plutonium (Pu) and highly enriched uranium (HEU)] in a form or condition that is substantially and inherently more difficult to recover and reuse in weapons production. This report is the data input report for the Programmatic Environmental Impact Statement (PEIS). The PEIS examines the environmental, safety, and health impacts of implementing each disposition alternative on land use, facility operations, and site infrastructure; air quality and noise; water, geology, and soils; biotic, cultural, and paleontological resources; socioeconomics; human health; normal operations and facility accidents; waste management; and transportation. This data report is prepared to assist in estimating the environmental effects associated with the construction and operation of a Deep Borehole Disposal Facility, an alternative currently included in the PEIS. The facility projects under consideration are, not site specific. This report therefore concentrates on environmental, safety, and health impacts at a generic site appropriate for siting a Deep Borehole Disposal Facility.

Fissile Material Disposition Program: Deep Borehole Disposal Facility PEIS data input report for direct disposal. Direct disposal of plutonium metal/plutonium dioxide in compound metal canisters. Version 3.0

International Nuclear Information System (INIS)

Wijesinghe, A.M.; Shaffer, R.J.

1996-01-01

The US Department of Energy (DOE) is examining options for disposing of excess weapons-usable nuclear materials [principally plutonium (Pu) and highly enriched uranium (HEU)] in a form or condition that is substantially and inherently more difficult to recover and reuse in weapons production. This report is the data input report for the Programmatic Environmental Impact Statement (PEIS). The PEIS examines the environmental, safety, and health impacts of implementing each disposition alternative on land use, facility operations, and site infrastructure; air quality and noise; water, geology, and soils; biotic, cultural, and paleontological resources; socioeconomics; human health; normal operations and facility accidents; waste management; and transportation. This data report is prepared to assist in estimating the environmental effects associated with the construction and operation of a Deep Borehole Disposal Facility, an alternative currently included in the PEIS. The facility projects under consideration are, not site specific. This report therefore concentrates on environmental, safety, and health impacts at a generic site appropriate for siting a Deep Borehole Disposal Facility

Plutonium immobilization project development and testing technical project office quality assurance program description

International Nuclear Information System (INIS)

Gould, T.H.; MacLean, L.M.; Ziemba, J.M.

1999-01-01

The Plutonium Immobilization Project (PIP) is one of several fissile materials disposition projects managed by the Department of Energy (DOE) Office of Fissile Materials Disposition (OFMD). The PIP is expected to evolve from the current Development and Testing (D and T) effort, to design, to construction, and finally to operations. Overall management and technical management of the D and T effort resides at the Lead Laboratory, Lawrence Livermore National Laboratory (LLNL), through the LLNL Manager, Fissile Materials Disposition Program (FMDP). Day to day project activities are managed by the D and T Technical Project Office (TPO), which reports to the LLNL Manager, FMDP. The D and T TPO consists of the Technical Manager, the TPO Quality Assurance (QA) Program Manager, and TPO Planning and Support Staff. This Quality Assurance Program Description (QAPD) defines the QA policies and controls that will be implemented by these TPO personnel in their management of D and T activities. This QAPD is consistent with and responsive to the Department of Energy Fissile Materials Disposition Program Quality Assurance Requirements Document (FMDP QARD). As the Project and upper level requirement's documents evolve, this QAPD will be updated as necessary to accurately define and describe the QA Program and Management of the PIP. The TPO has a policy that all development and testing activities be planned, performed and assessed in accordance with its customer's requirements, needs and expectations, and with a commitment to excellence and continuous improvement. The TPO QAPD describes implementation requirements which, when completed, will ensure that the project development and testing activities conform to the appropriate QA requirements. For the program to be effective, the TPO QA Program Manager will ensure that each site participating in D and T activities has developed a QAPD, which meets the customer's requirements, and has a designated quality leader in place. These customer

Supplement to the Surplus Plutonium Disposition Draft Environmental Impact Statement

Energy Technology Data Exchange (ETDEWEB)

N/A

1999-05-14

On May 22, 1997, DOE published a Notice of Intent in the Federal Register (62 Federal Register 28009) announcing its decision to prepare an environmental impact statement (EIS) that would tier from the analysis and decisions reached in connection with the ''Storage and Disposition of Weapons-Usable Fissile Materials Final Programmatic EIS (Storage and Disposition PEIS)''. ''The Surplus Plutonium Disposition Draft Environmental Impact Statement'' (SPD Draft EIS) (DOWEIS-0283-D) was prepared in accordance with NEPA and issued in July 1998. It identified the potential environmental impacts of reasonable alternatives for the proposed siting, construction, and operation of three facilities for plutonium disposition. These three facilities would accomplish pit disassembly and conversion, immobilization, and MOX fuel fabrication. For the alternatives that included MOX fuel fabrication, the draft also described the potential environmental impacts of using from three to eight commercial nuclear reactors to irradiate MOX fuel. The potential impacts were based on a generic reactor analysis that used actual reactor data and a range of potential site conditions. In May 1998, DCE initiated a procurement process to obtain MOX fuel fabrication and reactor irradiation services. The request for proposals defined limited activities that may be performed prior to issuance of the SPD EIS Record of Decision (ROD) including non-site-specific work associated with the development of the initial design for the MOX fuel fabrication facility, and plans (paper studies) for outreach, long lead-time procurements, regulatory management, facility quality assurance, safeguards, security, fuel qualification, and deactivation. No construction on the proposed MOX facility would begin before an SPD EIS ROD is issued. In March 1999, DOE awarded a contract to Duke Engineering & Services; COGEMA, Inc.; and Stone & Webster (known as DCS) to provide the requested

Supplement to the Surplus Plutonium Disposition Draft Environmental Impact Statement

International Nuclear Information System (INIS)

1999-01-01

On May 22, 1997, DOE published a Notice of Intent in the Federal Register (62 Federal Register 28009) announcing its decision to prepare an environmental impact statement (EIS) that would tier from the analysis and decisions reached in connection with the ''Storage and Disposition of Weapons-Usable Fissile Materials Final Programmatic EIS (Storage and Disposition PEIS)''. ''The Surplus Plutonium Disposition Draft Environmental Impact Statement'' (SPD Draft EIS) (DOWEIS-0283-D) was prepared in accordance with NEPA and issued in July 1998. It identified the potential environmental impacts of reasonable alternatives for the proposed siting, construction, and operation of three facilities for plutonium disposition. These three facilities would accomplish pit disassembly and conversion, immobilization, and MOX fuel fabrication. For the alternatives that included MOX fuel fabrication, the draft also described the potential environmental impacts of using from three to eight commercial nuclear reactors to irradiate MOX fuel. The potential impacts were based on a generic reactor analysis that used actual reactor data and a range of potential site conditions. In May 1998, DCE initiated a procurement process to obtain MOX fuel fabrication and reactor irradiation services. The request for proposals defined limited activities that may be performed prior to issuance of the SPD EIS Record of Decision (ROD) including non-site-specific work associated with the development of the initial design for the MOX fuel fabrication facility, and plans (paper studies) for outreach, long lead-time procurements, regulatory management, facility quality assurance, safeguards, security, fuel qualification, and deactivation. No construction on the proposed MOX facility would begin before an SPD EIS ROD is issued. In March 1999, DOE awarded a contract to Duke Engineering and Services; COGEMA, Inc.; and Stone and Webster (known as DCS) to provide the requested services. The procurement process

A treaty on the cutoff of fissile material for nuclear weapons - What to cover? How to verify?

International Nuclear Information System (INIS)

Schaper, A.

1998-01-01

Since 1946, a cutoff has been proposed. In 1993, the topic was placed on the agenda of the CD. The establishment of an Ad Hoc Committee in the CD with a mandate to negotiate a fissile material cutoff treaty struggled with difficulties for more than a year. The central dispute was whether the mandate should refer to existing un-safeguarded stockpiles. The underlying conflict of the CTBT negotiations can be summarized as nuclear disarmament versus nuclear nonproliferation The same conflict is now blocking progress with FMCT negotiations in the CD. At the center of technical proliferation concerns is direct use material that can be used for nuclear warheads without any further enrichment or reprocessing. Those materials are plutonium and highly enriched uranium (HEU). A broader category of materials is defined as all those containing any fissile isotopes, called special fissionable materials. In order ta verify that no direct use materials are abused for military purposes, also special fissionable materials must be controlled. An even broader category is simply called nuclear materials. Pu and HEU can be distinguished into the following categories of utilisation: 1. military direct use material in operational nuclear weapons and their logistics pipeline, 2. military direct use material held in reserve for military purposes, in assembled weapons or in other forms, 3. military direct use material withdrawn from dismantled weapons, 4. military direct use material considered excess and designated for transfer into civilian use, 5. military direct use material considered excess and declared for transfer into civilian use, 6. direct use material currently in reactors or their logistics pipelines and storages, and 7. irradiated Pu and HEU in spent fuel from reactors, or in vitrified form for final disposal. Large quantities of materials are neither inside weapons nor declared excess. So far, there are no legal obligations for NWS for limitations, declarations, or

HEU to LEU conversion and blending facility: Oxide blending alternative to produce LEU oxide for commercial use

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

The United States Department of Energy (DOE) is examining options for the disposition of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials. Disposition is a process of use or disposal of material that results in the material being converted to a form that is substantially and inherently more proliferation-resistant than the original form. Examining options for increasing the proliferation resistance of highly enriched uranium (HEU) is part of this effort. This document provides data to be used in the environmental impact analysis for the oxide blending HEU disposition option. This option provides for a yearly HEU throughput of 1 0 metric tons (MT) of uranium metal with an average U235 assay of 50% blended with 165 MT of natural assay triuranium octoxide (U{sub 3} O{sub 8}) per year to produce 177 MT of 4% U235 assay U{sub 3} O{sub 8}, for LWR fuel. Since HEU exists in a variety of forms and not necessarily in the form to be blended, worst case scenarios for preprocessing prior to blending will be assumed for HEU feed streams.

Development for fissile assay in recycled fuel using lead slowing down spectrometer

International Nuclear Information System (INIS)

Lee, Yong Deok; Je Park, C.; Kim, Ho-Dong; Song, Kee Chan

2013-01-01

A future nuclear energy system is under development to turn spent fuels produced by PWRs into fuels for a SFR (Sodium Fast Reactor) through the pyrochemical process. The knowledge of the isotopic fissile content of the new fuel is very important for fuel safety. A lead slowing down spectrometer (LSDS) is under development to analyze the fissile material content (Pu 239 , Pu 241 and U 235 ) of the fuel. The LSDS requires a neutron source, the neutrons will be slowed down through their passage in a lead medium and will finally enter the fuel and will induce fission reactions that will be analysed and the isotopic content of the fuel will be then determined. The issue is that the spent fuel emits intense gamma rays and neutrons by spontaneous fission. The threshold fission detector screens the prompt fast fission neutrons and as a result the LSDS is not influenced by the high level radiation background. The energy resolution of LSDS is good in the range 0.1 eV to 1 keV. It is also the range in which the fission reaction is the most discriminating for the considered fissile isotopes. An electron accelerator has been chosen to produce neutrons with an adequate target through (e - ,γ)(γ,n) reactions

Reduction of the uncertainty due to fissile clusters in radioactive waste characterization with the Differential Die-away Technique

Science.gov (United States)

Antoni, R.; Passard, C.; Perot, B.; Guillaumin, F.; Mazy, C.; Batifol, M.; Grassi, G.

2018-07-01

AREVA NC is preparing to process, characterize and compact old used fuel metallic waste stored at La Hague reprocessing plant in view of their future storage ("Haute Activité Oxyde" HAO project). For a large part of these historical wastes, the packaging is planned in CSD-C canisters ("Colis Standard de Déchets Compacté s") in the ACC hulls and nozzles compaction facility ("Atelier de Compactage des Coques et embouts"). . This paper presents a new method to take into account the possible presence of fissile material clusters, which may have a significant impact in the active neutron interrogation (Differential Die-away Technique) measurement of the CSD-C canisters, in the industrial neutron measurement station "P2-2". A matrix effect correction has already been investigated to predict the prompt fission neutron calibration coefficient (which provides the fissile mass) from an internal "drum flux monitor" signal provided during the active measurement by a boron-coated proportional counter located in the measurement cavity, and from a "drum transmission signal" recorded in passive mode by the detection blocks, in presence of an AmBe point source in the measurement cell. Up to now, the relationship between the calibration coefficient and these signals was obtained from a factorial design that did not consider the potential for occurrence of fissile material clusters. The interrogative neutron self-shielding in these clusters was treated separately and resulted in a penalty coefficient larger than 20% to prevent an underestimation of the fissile mass within the drum. In this work, we have shown that the incorporation of a new parameter in the factorial design, representing the fissile mass fraction in these clusters, provides an alternative to the penalty coefficient. This new approach finally does not degrade the uncertainty of the original prediction, which was calculated without taking into consideration the possible presence of clusters. Consequently, the

Analyse of the potential of the high temperature reactor with respect to the use of fissile materials; Analyse des capacites des reacteurs a haute temperature sous l'aspect de l'utilisation des matieres fissiles

Energy Technology Data Exchange (ETDEWEB)

Damian, F

2001-07-01

The high temperature reactors fuel is made of micro-particles dispersed in a graphite matrix. This configuration makes it possible to reach high burnup, higher than 700 GWj/t. Thanks to the decoupling between the thermal and the neutronic behaviors in the core many types of fuels can be used. These characteristics give to HTR reactor very good capacities to burn fissile materials. This work was done in the frame of the evaluation of HTR capacities to enhance the value of the plutonium stocks. These stocks are currently composed of the irradiated fuels discharged from classical PWR or the dismantling of the nuclear weapons and represent a significant energy potential. These studies concluded that high cycles length can be reached whatever the plutonium quality is (from 50 % to 94 % of fissile plutonium). In addition, it was demonstrated that the moderator temperature coefficient becomes locally positive for highly burn fuel while the core global moderator temperature coefficient remained negative in the operation range of the reactor. A significant share of this work was first devoted to the setting of a modeling of the fuel element but also of the reactor's core with the codes of system SAPHYR. The whole of modeling was validated by reference calculations. This work of code assessment is justified by a preliminary work that showed that the classical calculation scheme used for PWR could not be transposed directly to HTR core. (author)

Evaluation of criticality criteria for fissile class II packages in transportation

International Nuclear Information System (INIS)

Thomas, J.T.

1976-01-01

The nuclear criticality safety of packages in transportation is explored systematically by a surface density representation of reflected array criticality of air-spaced units. Typical perturbations to arrays are shown to be related analytically to the corresponding reactivity changes they produce. The reactivity change associated with the removal of three reflecting surfaces from a totally water reflected array is shown to depend upon the fissile material loading of the packages. For U(93.2) metal, the expected reactivity loss can range from 2 to 21%. Replacement of a three-sided reflector of water on a critical array by one of concrete results in a reactivity increase ranging from 0 to 6%. Mass limits established by criticality data for reflected arrays of air-spaced units can provide a minimum, uniform margin of safety, expressible in terms of reactivity, to more reliably specify subcriticality in transport. Mass limits less than those defined by air-spaced units in water-reflected arrays are unnecessary for Fissile Class II packages. (author)

HEU to LEU Conversion and Blending Facility: UNH blending alternative to produce LEU UNH for commercial use

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

US DOE is examining options for disposing of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials. The nuclear material is converted to a form that is more proliferation-resistant than the original form. Examining options for increasing the proliferation resistance of highly enriched uranium (HEU) is part of this effort. Five technologies for blending HEU will be assessed. This document provides data to be used in the environmental impact analysis for the UNH blending HEU disposition option. Process requirements, resource needs, employment needs, waste/emissions from plant, hazards, accident scenarios, and intersite transportation are discussed.

Feasibility of fissile mass assay of spent nuclear fuel using 252Cf-source-driven frequency-analysis

International Nuclear Information System (INIS)

Mattingly, J.K.; Valentine, T.E.; Mihalczo, J.T.

1996-01-01

The feasibility was evaluated using MCNP-DSP, an analog Monte Carlo transport cod to simulate source-driven measurements. Models of an isolated Westinghouse 17x17 PWR fuel assembly in a 1500-ppM borated water storage pool were used. In the models, the fuel burnup profile was represented using seven axial burnup zones, each with isotopics estimated by the PDQ code. Four different fuel assemblies with average burnups from fresh to 32 GWd/MTU were modeled and analyzed. Analysis of the fuel assemblies was simulated by inducing fission in the fuel using a 252 Cf source adjacent to the assembly and correlating source fissions with the response of a bank of 3 He detectors adjacent to the assembly opposite the source. This analysis was performed at 7 different axial positions on each of the 4 assemblies, and the source-detector cross-spectrum signature was calculated for each of these 28 simulated measurements. The magnitude of the cross-spectrum signature follows a smooth upward trend with increasing fissile material ( 235 U and 239 Pu) content, and the signature is independent of the concentration of spontaneously fissioning isotopes (e.g., 244 Cm) and (α,n) sources. Furthermore, the cross-spectrum signature is highly sensitive to changes in fissile material content. This feasibility study indicated that the signature would increase ∼100% in response to an increase of only 0.1 g/cm 3 of fissile material

Waste forms for plutonium disposition

International Nuclear Information System (INIS)

Johnson, S.G.; O'Holleran, T.P.; Frank, S.M.; Meyer, M.K.; Hanson, M.; Staples, B.A.; Knecht, D.A.; Kong, P.C.

1997-01-01

The field of plutonium disposition is varied and of much importance, since the Department of Energy has decided on the hybrid option for disposing of the weapons materials. This consists of either placing the Pu into mixed oxide fuel for reactors or placing the material into a stable waste form such as glass. The waste form used for Pu disposition should exhibit certain qualities: (1) provide for a suitable deterrent to guard against proliferation; (2) be of minimal volume, i.e., maximize the loading; and (3) be reasonably durable under repository-like conditions. This paper will discuss several Pu waste forms that display promising characteristics

Integrated development and testing plan for the plutonium immobilization project

International Nuclear Information System (INIS)

Kan, T.

1998-01-01

This integrated plan for the DOE Office of Fissile Materials Disposition (MD) describes the technology development and major project activities necessary to support the deployment of the immobilization approach for disposition of surplus weapons-usable plutonium. The plan describes details of the development and testing (D and T) tasks needed to provide technical data for design and operation of a plutonium immobilization plant based on the ceramic can-in-canister technology (''Immobilization Fissile Material Disposition Program Final Immobilization Form Assessment and Recommendation'', UCRL-ID-128705, October 3, 1997). The plan also presents tasks for characterization and performance testing of the immobilization form to support a repository licensing application and to develop the basis for repository acceptance of the plutonium form. Essential elements of the plant project (design, construction, facility activation, etc.) are described, but not developed in detail, to indicate how the D and T results tie into the overall plant project. Given the importance of repository acceptance, specific activities to be conducted by the Office of Civilian Radioactive Waste Management (RW) to incorporate the plutonium form in the repository licensing application are provided in this document, together with a summary of how immobilization D and T activities provide input to the license activity. The ultimate goal of the Immobilization Project is to develop, construct, and operate facilities that will immobilize from about 18 to 50 tonnes (MT) of U.S. surplus weapons usable plutonium materials in a manner that meets the ''spent fuel'' standard (Fissile Materials Storage and Disposition Programmatic Environmental Impact Statement Record of Decision, ''Storage and Disposition Final PEIS'', issued January 14, 1997, 62 Federal Register 3014) and is acceptable for disposal in a geologic repository. In the can-in-canister technology, this is accomplished by encapsulating the

High-power, photofission-inducing bremsstrahlung source for intense pulsed active detection of fissile material

Directory of Open Access Journals (Sweden)

J. C. Zier

2014-06-01

Full Text Available Intense pulsed active detection (IPAD is a promising technique for detecting fissile material to prevent the proliferation of special nuclear materials. With IPAD, fissions are induced in a brief, intense radiation burst and the resulting gamma ray or neutron signals are acquired during a short period of elevated signal-to-noise ratio. The 8 MV, 200 kA Mercury pulsed-power generator at the Naval Research Laboratory coupled to a high-power vacuum diode produces an intense 30 ns bremsstrahlung beam to study this approach. The work presented here reports on Mercury experiments designed to maximize the photofission yield in a depleted-uranium (DU object in the bremsstrahlung far field by varying the anode-cathode (AK diode gap spacing and by adding an inner-diameter-reducing insert in the outer conductor wall. An extensive suite of diagnostics was fielded to measure the bremsstrahlung beam and DU fission yield as functions of diode geometry. Delayed fission neutrons from the DU proved to be a valuable diagnostic for measuring bremsstrahlung photons above 5 MeV. The measurements are in broad agreement with particle-in-cell and Monte Carlo simulations of electron dynamics and radiation transport. These show that with increasing AK gap, electron losses to the insert and outer conductor wall increase and that the electron angles impacting the bremsstrahlung converter approach normal incidence. The diode conditions for maximum fission yield occur when the gap is large enough to produce electron angles close to normal, yet small enough to limit electron losses.

High-power, photofission-inducing bremsstrahlung source for intense pulsed active detection of fissile material

Science.gov (United States)

Zier, J. C.; Mosher, D.; Allen, R. J.; Commisso, R. J.; Cooperstein, G.; Hinshelwood, D. D.; Jackson, S. L.; Murphy, D. P.; Ottinger, P. F.; Richardson, A. S.; Schumer, J. W.; Swanekamp, S. B.; Weber, B. V.

2014-06-01

Intense pulsed active detection (IPAD) is a promising technique for detecting fissile material to prevent the proliferation of special nuclear materials. With IPAD, fissions are induced in a brief, intense radiation burst and the resulting gamma ray or neutron signals are acquired during a short period of elevated signal-to-noise ratio. The 8 MV, 200 kA Mercury pulsed-power generator at the Naval Research Laboratory coupled to a high-power vacuum diode produces an intense 30 ns bremsstrahlung beam to study this approach. The work presented here reports on Mercury experiments designed to maximize the photofission yield in a depleted-uranium (DU) object in the bremsstrahlung far field by varying the anode-cathode (AK) diode gap spacing and by adding an inner-diameter-reducing insert in the outer conductor wall. An extensive suite of diagnostics was fielded to measure the bremsstrahlung beam and DU fission yield as functions of diode geometry. Delayed fission neutrons from the DU proved to be a valuable diagnostic for measuring bremsstrahlung photons above 5 MeV. The measurements are in broad agreement with particle-in-cell and Monte Carlo simulations of electron dynamics and radiation transport. These show that with increasing AK gap, electron losses to the insert and outer conductor wall increase and that the electron angles impacting the bremsstrahlung converter approach normal incidence. The diode conditions for maximum fission yield occur when the gap is large enough to produce electron angles close to normal, yet small enough to limit electron losses.

UF6 fissile mass flow simulation at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Mihalczo, J.T.; March-Leuba, J.; Valentine, T.E.; Mattingly, J.K.; Uckan, T.; McEvers, J.A.

1997-01-01

Basis for measuring fissile mass flow in slurries, liquid, and gaseous streams is activation of a fissile stream by neutrons and then detection of delayed radiation from resulting fission products. This paper describes recent simulation measurements with the first prototype of the system for fissile mass flow measurements with HEU UF 6 gas for use in blenddown facilities. Theory was only 15% higher than actual measured; thus calibration factor would be 0.85. This simulation of HEU gas flow confirms well the understanding of the physical phenomena associated with this measurement system

Accelerator based production of fissile nuclides, threshold uranium price and perspectives

International Nuclear Information System (INIS)

Djordjevic, D.; Knapp, V.

1988-01-01

Accelerator breeder system characteristics are considered in this work. One such system which produces fissile nuclides can supply several thermal reactors with fissile fuel, so this system becomes analogous to an uranium enrichment facility with difference that fissile nuclides are produced by conversion of U-238 rather than by separation from natural uranium. This concept, with other long-term perspective for fission technology on the basis of development only one simpler technology. The influence of basic system characteristics on threshold uranium price is examined. Conditions for economically acceptable production are established. (author)

Hanford MOX fuel lead assemblies data report for the surplus plutonium disposition environmental impact statement

International Nuclear Information System (INIS)

O'Connor, D.G.; Fisher, S.E.; Holdaway, R.

1998-08-01

The purpose of this document is to support the US Department of Energy (DOE) Fissile Materials Disposition Program's preparation of the draft surplus plutonium disposition environmental impact statement. This is one of several responses to data call requests for background information on activities associated with the operation of the lead assembly (LA) mixed-oxide (MOX) fuel fabrication facility. DOE-MD requested that the DOE Site Operations Offices nominate DOE sites that meet established minimum requirements that could produce MOX LAs. Six initial site combinations were proposed: (1) Argonne National Laboratory-West (ANL-W) with support from Idaho National Engineering and Environmental Laboratory (INEEL), (2) Hanford, (3) Los Alamos National Laboratory (LANL) with support from Pantex, (4) Lawrence Livermore National Laboratory (LLNL), (5) Oak Ridge Reservation (ORR), and (6) Savannah River Site (SRS). After further analysis by the sites and DOE-MD, five site combinations were established as possible candidates for producing MOX LAs: (1) ANL-W with support from INEEL, (2) Hanford, (3) LANL, (4) LLNL, and (5) SRS. Hanford has proposed an LA MOX fuel fabrication approach that would be done entirely inside an S and S Category 1 area. An alternate approach would allow fabrication of fuel pellets and assembly of fuel rods in an S and S Category 1 facility. In all, a total of three LA MOX fuel fabrication options were identified by Hanford that could accommodate the program. In every case, only minor modification would be required to ready any of the facilities to accept the equipment necessary to accomplish the LA program

Hanford MOX fuel lead assemblies data report for the surplus plutonium disposition environmental impact statement

Energy Technology Data Exchange (ETDEWEB)

O`Connor, D.G.; Fisher, S.E.; Holdaway, R. [and others

1998-08-01

The purpose of this document is to support the US Department of Energy (DOE) Fissile Materials Disposition Program`s preparation of the draft surplus plutonium disposition environmental impact statement. This is one of several responses to data call requests for background information on activities associated with the operation of the lead assembly (LA) mixed-oxide (MOX) fuel fabrication facility. DOE-MD requested that the DOE Site Operations Offices nominate DOE sites that meet established minimum requirements that could produce MOX LAs. Six initial site combinations were proposed: (1) Argonne National Laboratory-West (ANL-W) with support from Idaho National Engineering and Environmental Laboratory (INEEL), (2) Hanford, (3) Los Alamos National Laboratory (LANL) with support from Pantex, (4) Lawrence Livermore National Laboratory (LLNL), (5) Oak Ridge Reservation (ORR), and (6) Savannah River Site (SRS). After further analysis by the sites and DOE-MD, five site combinations were established as possible candidates for producing MOX LAs: (1) ANL-W with support from INEEL, (2) Hanford, (3) LANL, (4) LLNL, and (5) SRS. Hanford has proposed an LA MOX fuel fabrication approach that would be done entirely inside an S and S Category 1 area. An alternate approach would allow fabrication of fuel pellets and assembly of fuel rods in an S and S Category 1 facility. In all, a total of three LA MOX fuel fabrication options were identified by Hanford that could accommodate the program. In every case, only minor modification would be required to ready any of the facilities to accept the equipment necessary to accomplish the LA program.

Analyse of the potential of the high temperature reactor with respect to the use of fissile materials; Analyse des capacites des reacteurs a haute temperature sous l'aspect de l'utilisation des matieres fissiles

Energy Technology Data Exchange (ETDEWEB)

Damian, F

2001-07-01

The high temperature reactors fuel is made of micro-particles dispersed in a graphite matrix. This configuration makes it possible to reach high burnup, higher than 700 GWj/t. Thanks to the decoupling between the thermal and the neutronic behaviors in the core many types of fuels can be used. These characteristics give to HTR reactor very good capacities to burn fissile materials. This work was done in the frame of the evaluation of HTR capacities to enhance the value of the plutonium stocks. These stocks are currently composed of the irradiated fuels discharged from classical PWR or the dismantling of the nuclear weapons and represent a significant energy potential. These studies concluded that high cycles length can be reached whatever the plutonium quality is (from 50 % to 94 % of fissile plutonium). In addition, it was demonstrated that the moderator temperature coefficient becomes locally positive for highly burn fuel while the core global moderator temperature coefficient remained negative in the operation range of the reactor. A significant share of this work was first devoted to the setting of a modeling of the fuel element but also of the reactor's core with the codes of system SAPHYR. The whole of modeling was validated by reference calculations. This work of code assessment is justified by a preliminary work that showed that the classical calculation scheme used for PWR could not be transposed directly to HTR core. (author)

Requirements for materials of dispersion fuel elements

International Nuclear Information System (INIS)

Samojlov, A.G.; Kashtanov, A.I.; Volkov, V.S.

1982-01-01

Requirements for materials of dispersion fuel elements are considered. The necessity of structural and fissile materials compatibility at maximum permissible operation temperatures and temperatures arising in a fuel element during manufacture is pointed out. The fuel element structural material must be ductile, possess high mechanical strength minimum neutron absorption cross section, sufficient heat conductivity, good corrosion resistance in a coolant and radiation resistance. The fissile material must have high fissile isotope concentration, radiation resistance, high thermal conductivity, certain porosity high melting temperature must not change the composition under irradiation

Savannah River Site's H-Canyon Facility: Impacts of Foreign Obligations on Special Nuclear Material Disposition

International Nuclear Information System (INIS)

Magoulas, Virginia

2013-01-01

The US has a non-proliferation policy to receive foreign and domestic research reactor returns of spent fuel materials of US origin. These spent fuel materials are returned to the Department of Energy (DOE) and placed in storage in the L-area spent fuel basin at the Savannah River Site (SRS). The foreign research reactor returns fall subject to the 123 agreements for peaceful cooperation. These ''123 agreements'' are named after section 123 of the Atomic Energy Act of 1954 and govern the conditions of nuclear cooperation with foreign partners. The SRS management of these foreign obligations while planning material disposition paths can be a challenge.

External Criticality Risk of Immobilized Plutonium Waste Form in a Geologic Repository

International Nuclear Information System (INIS)

McClure, J.

2001-01-01

This purpose of this technical report is to provide a comprehensive summary of the waste package (WP) external criticality-related risk of the Plutonium Disposition ceramic waste form, which is being developed and evaluated by the Office of Fissile Materials Disposition of the United States Department of Energy (DOE). Potential accumulation of the fissile materials, 239 Pu and 235 U, in rock formations having a favorable chemical environment for such actions, requires analysis because autocatalytic configurations, while unlikely to form, never-the-less have consequences which are undesirable and require evaluation. Secondly, the WP design has evolved necessitating a re-evaluation of the internal WP degradation scenarios that contribute to the external source terms. The scope of this study includes a summary of the revised WP degradation calculations, a summary of the accumulation mechanisms in fractures and lithophysae in the tuff beneath the WP footprint, and a summary of the criticality risk calculations from any accumulated fissile material. Accumulations of fissile material external to the WP sufficient to pose a potential criticality risk require a deposition mechanism operating over sufficient time to reach required levels. The transporting solution concentrations themselves are well below critical levels (CRWMS 2001e). The ceramic waste form consists of Pu immobilized in ceramic disks, which would be embedded in High-Level Waste (HLW) glass in the standard HLW glass disposal canister. The ceramic disks would occupy approximately 12% of the HLW canister volume, while most of the remaining 88% of the volume would be occupied by HLW glass

Analysis of triso packing fraction and fissile material to DB-MHR using LWR reprocessed fuel

International Nuclear Information System (INIS)

Silva, Clarysson A.M. da; Pereira, Claubia; Costa, Antonella L.; Veloso, Maria Auxiliadora F.; Gual, Maritza R.

2013-01-01

Gas-cooled and graphite-moderated reactor is being considered the next generation of nuclear power plants because of its characteristic to operate with reprocessed fuel. The typical fuel element consists of a hexagonal block with coolant and fuel channels. The fuel pin is manufactured into compacted ceramic-coated particles (TRISO) which are used to achieve both a high burnup and a high degree of passive safety. This work uses the MCNPX 2.6.0 to simulate the active core of Deep Burn Modular Helium Reactor (DB-MHR) employing PWR (Pressurized Water Reactor) reprocessed fuel. However, before a complete study of DB-MHR fuel cycle and recharge, it is necessary to evaluate the neutronic parameters to some values of TRISO Packing Fractions (PF) and Fissile Material (FM). Each PF and FM combination would generate the best behaviour of neutronic parameters. Therefore, this study configures several PF and FM combinations considering the heterogeneity of TRISO layers and lattice. The results present the best combination of PF and FM values according with the more appropriated behaviour of the neutronic parameters during the burnup. In this way, the optimized combination can be used to future works of MHR fuel cycle and recharge. (author)

High order statistical signatures from source-driven measurements of subcritical fissile systems

International Nuclear Information System (INIS)

Mattingly, J.K.

1998-01-01

This research focuses on the development and application of high order statistical analyses applied to measurements performed with subcritical fissile systems driven by an introduced neutron source. The signatures presented are derived from counting statistics of the introduced source and radiation detectors that observe the response of the fissile system. It is demonstrated that successively higher order counting statistics possess progressively higher sensitivity to reactivity. Consequently, these signatures are more sensitive to changes in the composition, fissile mass, and configuration of the fissile assembly. Furthermore, it is shown that these techniques are capable of distinguishing the response of the fissile system to the introduced source from its response to any internal or inherent sources. This ability combined with the enhanced sensitivity of higher order signatures indicates that these techniques will be of significant utility in a variety of applications. Potential applications include enhanced radiation signature identification of weapons components for nuclear disarmament and safeguards applications and augmented nondestructive analysis of spent nuclear fuel. In general, these techniques expand present capabilities in the analysis of subcritical measurements

21 CFR 111.113 - What quality control operations are required for a material review and disposition decision?

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false What quality control operations are required for a... Production and Process Control System: Requirements for Quality Control § 111.113 What quality control operations are required for a material review and disposition decision? (a) Quality control personnel must...

Development of a fissile particle for HTGR fuel recycle

International Nuclear Information System (INIS)

Homan, F.J.; Long, E.L. Jr.; Lindemer, T.B.; Beatty, R.L.; Tiegs, T.N.

1976-12-01

Recycle fissile fuel particles for high-temperature gas-cooled reactors (HTGRs) have been under development since the mid-1960s. Irradiation performance on early UO 2 and Th 0 . 8 U 0 . 2 O 2 kernels is described in this report, and the performance limitations associated with the dense oxide kernels are presented. The development of the new reference fuel kernel, the weak-acid-resin-derived (WAR) UO 2 --UC 2 , is discussed in detail, including an extensive section on the irradiation performance of this fuel in HFIR removable beryllium capsules HRB-7 through -10. The conclusion is reached that the irradiation performance of the WAR fissile fuel kernel is better than that of any coated particle fuel yet tested. Further, the present fissile kernel is adequate for steam cycle HTGRs as well as for many advanced applications such as gas turbine and process heat HTGRs

Programmatic and technical requirements for the FMDP fresh MOX fuel transport package

International Nuclear Information System (INIS)

Ludwig, S.B.; Michelhaugh, R.D.; Pope, R.B.

1997-12-01

This document is intended to guide the designers of the package to all pertinent regulatory and other design requirements to help ensure the safe and efficient transport of the weapons-grade (WG) fresh MOX fuel under the Fissile Materials Disposition Program. To accomplish the disposition mission using MOX fuel, the unirradiated MOX fuel must be transported from the MOX fabrication facility to one or more commercial reactors. Because the unirradiated fuel contains large quantities of plutonium and is not sufficient radioactive to create a self-protecting barrier to deter the material from theft, DOE intends to use its fleet of safe secure trailers (SSTs) to provide the necessary safeguards and security for the material in transit. In addition to these requirements, transport of radioactive materials must comply with regulations of the Department of Transportation and the Nuclear Regulatory Commission (NRC). In particular, NRC requires that the packages must meet strict performance requirements. The requirements for shipment of MOX fuel (i.e., radioactive fissile materials) specify that the package design is certified by NRC to ensure the materials contained in the packages are not released and remain subcritical after undergoing a series of hypothetical accident condition tests. Packages that pass these tests are certified by NRC as a Type B fissile (BF) package. This document specifies the programmatic and technical design requirements a package must satisfy to transport the fresh MOX fuel assemblies

Trilateral Initiative: IAEA authentication and national certification of verification equipment for facilities with classified forms of fissile material

International Nuclear Information System (INIS)

Haas, Eckard; Sukhanov, Alexander; Murphy, John

2001-01-01

Full text: Within the framework of the Trilateral Initiative, technical challenges have arisen due to the potential of the International Atomic Energy Agency (IAEA) monitoring fissile material with classified characteristics, as well as the IAEA using facility or host country supplied monitoring equipment. In monitoring material with classified characteristics, it is recognized that the host country needs to assure that classified information is not made available to the IAEA inspectors. Thus, any monitoring equipment used to monitor material with classified characteristics has to contain information security capabilities, such as information barriers. But likewise in using host-country-supplied monitoring equipment, regarding the material being monitored the IAEA has to have confidence that the information provided by the equipment is genuine and can be used by the IAEA in fulfilling its obligation to derive conclusions based on independent verification measures. Thus the IAEA needs to go through the process of authenticating the monitoring equipment. In the same way the host country needs to go through the process to assure itself that the monitoring equipment integrated with an information barrier will not divulge any classified information about an inspected sensitive item. Both processes require on large extent identical measures, but partially also may conflict with each other. The fact that monitoring equipment needs to exhibit information security throughout its lifecycle while at the same time be capable of being authenticated necessitates the need for creative technical approaches to be pursued. (author)

Fusion-Fission Hybrid for Fissile Fuel Production without Processing

Energy Technology Data Exchange (ETDEWEB)

Fratoni, M; Moir, R W; Kramer, K J; Latkowski, J F; Meier, W R; Powers, J J

2012-01-02

Two scenarios are typically envisioned for thorium fuel cycles: 'open' cycles based on irradiation of {sup 232}Th and fission of {sup 233}U in situ without reprocessing or 'closed' cycles based on irradiation of {sup 232}Th followed by reprocessing, and recycling of {sup 233}U either in situ or in critical fission reactors. This study evaluates a third option based on the possibility of breeding fissile material in a fusion-fission hybrid reactor and burning the same fuel in a critical reactor without any reprocessing or reconditioning. This fuel cycle requires the hybrid and the critical reactor to use the same fuel form. TRISO particles embedded in carbon pebbles were selected as the preferred form of fuel and an inertial laser fusion system featuring a subcritical blanket was combined with critical pebble bed reactors, either gas-cooled or liquid-salt-cooled. The hybrid reactor was modeled based on the earlier, hybrid version of the LLNL Laser Inertial Fusion Energy (LIFE1) system, whereas the critical reactors were modeled according to the Pebble Bed Modular Reactor (PBMR) and the Pebble Bed Advanced High Temperature Reactor (PB-AHTR) design. An extensive neutronic analysis was carried out for both the hybrid and the fission reactors in order to track the fuel composition at each stage of the fuel cycle and ultimately determine the plant support ratio, which has been defined as the ratio between the thermal power generated in fission reactors and the fusion power required to breed the fissile fuel burnt in these fission reactors. It was found that the maximum attainable plant support ratio for a thorium fuel cycle that employs neither enrichment nor reprocessing is about 2. This requires tuning the neutron energy towards high energy for breeding and towards thermal energy for burning. A high fuel loading in the pebbles allows a faster spectrum in the hybrid blanket; mixing dummy carbon pebbles with fuel pebbles enables a softer spectrum in

Repository and deep borehole disposition of plutonium

International Nuclear Information System (INIS)

Halsey, W.G.

1996-02-01

Control and disposition of excess weapons plutonium is a growing issue as both the US and Russia retire a large number of nuclear weapons> A variety of options are under consideration to ultimately dispose of this material. Permanent disposition includes tow broad categories: direct Pu disposal where the material is considered waste and disposed of, and Pu utilization, where the potential energy content of the material is exploited via fissioning. The primary alternative to a high-level radioactive waste repository for the ultimate disposal of plutonium is development of a custom geologic facility. A variety of geologic facility types have been considered, but the concept currently being assessed is the deep borehole

The simultaneous neutron and photon interrogation method for fissile and non-fissile element separation in radioactive waste drums

International Nuclear Information System (INIS)

Jallu, F.; Lyoussi, A.; Passard, C.; Payan, E.; Recroix, H.; Nurdin, G.; Buisson, A.; Allano, J.

2000-01-01

Measuring α-emitters such as ( 234,235,236,238 U, 238,239,240,242,244 Pu, 237 Np, 241,243 Am, ...), in solid radioactive waste allows us to quantify the α-activity in a drum and then to classify it. The simultaneous photon and neutron interrogation experiment (SIMPHONIE) method dealt with in this paper, combines both active neutron interrogation and induced photofission interrogation techniques simultaneously. Its purpose is to quantify fissile ( 235 U, 239,241 Pu, ...) and non-fissile ( 236,238 U, 238,240 Pu, ...) elements separately in only one measurement. This paper presents the principle of the method, the experimental setup, and the first experimental results obtained using the DGA/ETCA Linac and MiniLinatron pulsed linear electron accelerators located at Arcueil, France. First studies were carried out with U and Pu bare samples

The differential dieaway technique applied to the measurement of the fissile content of drums of cement encapsulated waste

International Nuclear Information System (INIS)

Swinhoe, M.T.

1986-01-01

This report describes calculations of the differential dieaway technique as applied to cement encapsulated waste. The main difference from previous applications of the technique are that only one detector position is used (diametrically opposite the neutron source) and the chamber walls are made of concrete. The results show that by rotating the drum the response to fissile material across the central plane of the drum can be made relatively uniform. The absolute size of the response is about 0.4. counts per minute per gram fissile for a neutron source of 10 8 neutrons per second. Problems of neutron and gamma background and water content are considered. (author)

Uranium-233 waste definition: Disposal options, safeguards, criticality control, and arms control

International Nuclear Information System (INIS)

Forsberg, C.W.; Storch, S.N.; Lewis, L.C.

1998-01-01

The US investigated the use of 233 U for weapons, reactors, and other purposes from the 1950s into the 1970s. Based on the results of these investigations, it was decided not to use 233 U on a large scale. Most of the 233 U-containing materials were placed in long-term storage. At the end of the cold war, the US initiated, as part of its arms control policies, a disposition program for excess fissile materials. Other programs were accelerated for disposal of radioactive wastes placed in storage during the cold war. Last, potential safety issues were identified related to the storage of some 233 U-containing materials. Because of these changes, significant activities associated with 233 U-containing materials are expected. This report is one of a series of reports to provide the technical bases for future decisions on how to manage this material. A basis for defining when 233 U-containing materials can be managed as waste and when they must be managed as concentrated fissile materials has been developed. The requirements for storage, transport, and disposal of radioactive wastes are significantly different than those for fissile materials. Because of these differences, it is important to classify material in its appropriate category. The establishment of a definition of what is waste and what is fissile material will provide the guidance for appropriate management of these materials. Wastes are defined in this report as materials containing sufficiently small masses or low concentrations of fissile materials such that they can be managed as typical radioactive waste. Concentrated fissile materials are defined herein as materials containing sufficient fissile content such as to warrant special handling to address nuclear criticality, safeguards, and arms control concerns

International conference on military conversion and science. Utilization/disposal of the excess fissile weapon materials: scientific, technological and socio-economic aspects

International Nuclear Information System (INIS)

Kouzminov, V.; Martellini, M.

1996-01-01

The Proceedings of the Conference includes the papers presented by the eminent specialists in the field of utilisation and/or disposal of excess fissile materials, each with a separate abstract, as well as the Conference opening and introduction speeches. According to the concerned subjects presentations were divided into following five sessions: perspectives of nuclear research and development; Technical problems and possibilities of civilian utilization of Highly enriched uranium (HEU) and plutonium including alternate strategies (application of MOX fuel) and operational and safety problems; Comparison of different options for weapon-grade Pu utilization connected to present programme for recycling of civilian Pu; Socio-economic aspects including cost of Pu conversion and fabrication of MOX fuel; Effects of different strategies of waste disposal including environmental and safety related issues

Testing in support of transportation of residues in the pipe overpack container

International Nuclear Information System (INIS)

Ammerman, D.J.; Bobbe, J.G.; Arviso, M.; Bronowski, D.R.

1997-04-01

The disposition of the large back-log of plutonium residues at the Rocky Flats Environmental Technology Site (Rocky Flats) will require interim storage and subsequent shipment to a waste repository. Current plants call for disposal at the Waste Isolation Pilot Plant (WIPP) and the transportation to WIPP in the TRUPACT-II. The transportation phase will require the residues to be packaged in a container that is more robust than a standard 55-gallon waste drum. Rocky Flats has designed the Pipe Overpack Container to meet this need. The tests described here were performed to qualify the Pipe Overpack Container as a waste container for shipment in the TRUPACT-II. Using a more robust container will assure the fissile materials in each container can not be mixed with the fissile material from the other containers and will provide criticality control. This will allow an increase in the payload of the TRUPACT-II from 325 fissile gram equivalents to 2,800 fissile gram equivalents

LANL MOX fuel lead assemblies data report for the surplus plutonium disposition environmental impact statement

International Nuclear Information System (INIS)

Fisher, S.E.; Holdaway, R.; Ludwig, S.B.

1998-08-01

The purpose of this document is to support the US Department of Energy (DOE) Fissile Materials Disposition Program's preparation of the draft surplus plutonium disposition environmental impact statement. This is one of several responses to data call requests for background information on activities associated with the operation of the lead assembly (LA) mixed-oxide (MOX) fuel fabrication facility. LANL has proposed an LA MOX fuel fabrication approach that would be done entirely inside an S and S Category 1 area. This includes receipt and storage of PuO 2 powder, fabrication of MOX fuel pellets, assembly of fuel rods and bundles, and shipping of the packaged fuel to a commercial reactor site. Support activities will take place within both Category 1 and 2 areas. Technical Area (TA) 55/Plutonium Facility 4 will be used to store the bulk PuO 2 powder, fabricate MOX fuel pellets, assemble rods, and store fuel bundles. Bundles will be assembled at a separate facility, several of which have been identified as suitable for that activity. The Chemistry and Metallurgy Research Building (at TA-3) will be used for analytical chemistry support. Waste operations will be conducted in TA-50 and TA-54. Only very minor modifications will be needed to accommodate the LA program. These modifications consist mostly of minor equipment upgrades. A commercial reactor operator has not been identified for the LA irradiation. Postirradiation examination (PIE) of the irradiated fuel will take place at either Oak Ridge National Laboratory or ANL-W. The only modifications required at either PIE site would be to accommodate full-length irradiated fuel rods. Results from this program are critical to the overall plutonium distribution schedule

Ternary fission of spontaneously fissile uranium isomers excited by neutrons

International Nuclear Information System (INIS)

Makarenko, V.E.; Molchanov, Y.D.; Otroshchenko, G.A.; Yan'kov, G.B.

1989-01-01

Spontaneously fissile isomers (SFI) of uranium were excited in the reactions 236,238 U(n,n') at an average neutron energy 4.5 MeV. A pulsed electrostatic accelerator and time analysis of the fission events were used. Fission fragments were detected by the scintillation method, and long-range particles from fission were detected by an ionization method. The relative probability of fission of nuclei through a spontaneously fissile isomeric state was measured: (1.30±0.01)·10 -4 ( 236 U) and (1.48±0.02)·10 -4 ( 238 U). Half-lives of the isomers were determined: 121±2 nsec (the SFI 236 U) and 267±13 nsec (the SFI 238 U). In study of the ternary fission of spontaneously fissile isotopes of uranium it was established that the probability of the process amounts to one ternary fission per 163±44 binary fissions of the SFI 236 U and one ternary fission per 49±14 binary fissions of the SFI 238 U. The substantial increase of the probability of ternary fission of SFI of uranium in comparison with the case of ternary fission of nuclei which are not in an isomeric state may be related to a special nucleon configuration of the fissile isomers of uranium

To the question of definition of fissile material mass and neutron multiplication in deep sub-critical systems

International Nuclear Information System (INIS)

Dulin, V.V.

2006-01-01

A method of determination neutrons multiplication in deep sub-critical multiplying media has been developed. It is based on a modified of Rossi - alpha method. It will consist in use of integral on time (a method of the areas) from correlated parts of distribution and integral in area, independent of time a part of distribution (area of a constant background). It allows to spend the calculated analysis, using the integrated equation on time for a neutrons flux and to not use representation of point kinetic model. A calculation spatially-correlation factor the adjoint (relative the detector count rate) inhomogeneous equation is used. Its calculation takes into account fission both in multiplying media and in a spontaneous neutron source. Measurements with plutonium-steel and uranium-steel blocks, and blocks from uranium and plutonium dioxide of different enrichment are have been carried out. The measured values of neutrons multiplication in a range 1.03-1.82 will be well coordinated to results of calculations. The question on an opportunity of definition of weight of the measured blocks of fissile material is considered [ru

Dispositional logic

Science.gov (United States)

Le Balleur, J. C.

1988-01-01

The applicability of conventional mathematical analysis (based on the combination of two-valued logic and probability theory) to problems in which human judgment, perception, or emotions play significant roles is considered theoretically. It is shown that dispositional logic, a branch of fuzzy logic, has particular relevance to the common-sense reasoning typical of human decision-making. The concepts of dispositionality and usuality are defined analytically, and a dispositional conjunctive rule and dispositional modus ponens are derived.

HEU to LEU Conversion and Blending Facility: UF6 blending alternative to produce LEU UF6 for commercial use

International Nuclear Information System (INIS)

1995-09-01

US DOE is examining options for disposing of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials; the nuclear material will be converted to a form more proliferation- resistant than the original form. Examining options for increasing the proliferation resistance of highly enriched uranium (HEU) is part of this effort. Five technologies for blending HEU will be assessed; blending as UF 6 to produce a UF 6 product for commercial use is one of them. This document provides data to be used in the environmental impact analysis for the UF 6 blending HEU disposition option. Resource needs, employment needs, waste and emissions from plant, hazards, accident scenarios, and intersite transportation are discussed

HEU to LEU Conversion and Blending Facility: UF{sub 6} blending alternative to produce LEU UF{sub 6} for commercial use

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

US DOE is examining options for disposing of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials; the nuclear material will be converted to a form more proliferation- resistant than the original form. Examining options for increasing the proliferation resistance of highly enriched uranium (HEU) is part of this effort. Five technologies for blending HEU will be assessed; blending as UF{sub 6} to produce a UF{sub 6} product for commercial use is one of them. This document provides data to be used in the environmental impact analysis for the UF{sub 6} blending HEU disposition option. Resource needs, employment needs, waste and emissions from plant, hazards, accident scenarios, and intersite transportation are discussed.

Counterstreaming-ion-tokamak fissile breeder

International Nuclear Information System (INIS)

Jassby, D.L.; Lee, J.D.

1976-08-01

Tokamak plasmas fueled and heated by energetic neutral-atom beams are characterized by total ion energy greatly exceeding the electron energy. For smaller devices the largest fusion reactivity of energetic-ion plasmas is obtained when oppositely injected D 0 and T 0 beams sustain counterstreaming velocity distributions of deuterons and tritons. This scoping study investigates the net fissile and power productions of a tokamak fusion-fission reactor with a counterstreaming-ion fusion driver and a fertile blanket optimized for fissile breeding. The fusion driver has parameters R/sub o/ = 4.7 m, a = 1.0 m, B/sub t/ = 5.6 T, W/sub b/ = 100 keV (D 0 ), n tau/sub E/ = 1.4 x 10 13 cm -3 s, Q = 1.5, 14-MeV neutron production = 175 MW. The blanket contains a fast-fission zone of natural U plus Mo (7 percent), followed by a Li-bearing zone for T breeding. The reactor produces a net power of 480 MWe and supplies sufficient Pu to support a system of LWR's producing 3800 MWe, with an estimated electrical energy cost for the entire system of 27 mills/kWh

Security of fissile materials in Russia

International Nuclear Information System (INIS)

Bukharin, O.

1996-01-01

The problem of security of huge stocks of weapons-usable highly enriched uranium and plutonium in Russia against theft or diversion remains a serious nonproliferation concern. During the Cold War, the security of Soviet nuclear materials was based on centralization and discipline, protection by the military, and intrusive political oversight of the people. The recent fundamental societal changes have rendered these arrangements inadequate, and the security of nuclear materials has decreased. Safeguarding nuclear materials in Russia is particularly difficult because of their very large inventories and the size and complexity of the nation's nuclear infrastructure. Russia needs a reliable and more objective technology-based system of nuclear safeguards designed to control nuclear materials. The Russian government and the international community are working towards this goal

Representing dispositions

Directory of Open Access Journals (Sweden)

Röhl Johannes

2011-08-01

Full Text Available Abstract Dispositions and tendencies feature significantly in the biomedical domain and therefore in representations of knowledge of that domain. They are not only important for specific applications like an infectious disease ontology, but also as part of a general strategy for modelling knowledge about molecular interactions. But the task of representing dispositions in some formal ontological systems is fraught with several problems, which are partly due to the fact that Description Logics can only deal well with binary relations. The paper will discuss some of the results of the philosophical debate about dispositions, in order to see whether the formal relations needed to represent dispositions can be broken down to binary relations. Finally, we will discuss problems arising from the possibility of the absence of realizations, of multi-track or multi-trigger dispositions and offer suggestions on how to deal with them.

Calculus of a reactor VVER-1000 benchmark; Calcul d'un benchmark de reacteur VVER-1000

Energy Technology Data Exchange (ETDEWEB)

Dourougie, C

1998-07-01

In the framework of the FMDP (Fissile Materials Disposition Program between the US and Russian, a benchmark was tested. The pin cells contain low enriched uranium (LEU) and mixed oxide fuels (MOX). The calculations are done for a wide range of temperatures and solute boron concentrations, in accidental conditions. (A.L.B.)

Calculus of a reactor VVER-1000 benchmark

International Nuclear Information System (INIS)

Dourougie, C.

1998-01-01

In the framework of the FMDP (Fissile Materials Disposition Program between the US and Russian, a benchmark was tested. The pin cells contain low enriched uranium (LEU) and mixed oxide fuels (MOX). The calculations are done for a wide range of temperatures and solute boron concentrations, in accidental conditions. (A.L.B.)

Digital Reading Disposition Scale: A Study of Validity and Reliability

Science.gov (United States)

Bulut, Berker; Karasakaloglu, Nuri

2018-01-01

In this study, "a Digital Reading Disposition Scale" was developed to determine undergraduate pre-service teacher students' dispositions towards digital reading, opposed to a preference for printed reading material. Initially, a 20-items trial version of the scale was administered to a total sample of N = 301 undergraduate pre-service…

A Methodology for the Analysis and Selection of Alternative for the Disposition of Surplus Plutonium

International Nuclear Information System (INIS)

1999-01-01

The Department of Energy (DOE) - Office of Fissile Materials Disposition (OFMD) has announced a Record of Decision (ROD) selecting alternatives for disposition of surplus plutonium. A major objective of this decision was to further U.S. efforts to prevent the proliferation of nuclear weapons. Other concerns that were addressed include economic, technical, institutional, schedule, environmental, and health and safety issues. The technical, environmental, and nonproliferation analyses supporting the ROD are documented in three DOE reports (DOE-TSR 96, DOE-PEIS 96, and DOE-NN 97, respectively). At the request of OFMD, a team of analysts from the Amarillo National Resource Center for Plutonium (ANRCP) provided an independent evaluation of the alternatives for plutonium that were considered during the evaluation effort. This report outlines the methodology used by the ANRCP team. This methodology, referred to as multiattribute utility theory (MAU), provides a structure for assembling results of detailed technical, economic, schedule, environment, and nonproliferation analyses for OFMD, DOE policy makers, other stakeholders, and the general public in a systematic way. The MAU methodology has been supported for use in similar situations by the National Research Council, an agency of the National Academy of Sciences.1 It is important to emphasize that the MAU process does not lead to a computerized model that actually determines the decision for a complex problem. MAU is a management tool that is one component, albeit a key component, of a decision process. We subscribe to the philosophy that the result of using models should be insights, not numbers. The MAU approach consists of four steps: (1) identification of alternatives, objectives, and performance measures, (2) estimation of the performance of the alternatives with respect to the objectives, (3) development of value functions and weights for the objectives, and (4) evaluation of the alternatives and sensitivity

LANL MOX fuel lead assemblies data report for the surplus plutonium disposition environmental impact statement

Energy Technology Data Exchange (ETDEWEB)

Fisher, S.E.; Holdaway, R.; Ludwig, S.B. [and others

1998-08-01

The purpose of this document is to support the US Department of Energy (DOE) Fissile Materials Disposition Program`s preparation of the draft surplus plutonium disposition environmental impact statement. This is one of several responses to data call requests for background information on activities associated with the operation of the lead assembly (LA) mixed-oxide (MOX) fuel fabrication facility. LANL has proposed an LA MOX fuel fabrication approach that would be done entirely inside an S and S Category 1 area. This includes receipt and storage of PuO{sub 2} powder, fabrication of MOX fuel pellets, assembly of fuel rods and bundles, and shipping of the packaged fuel to a commercial reactor site. Support activities will take place within both Category 1 and 2 areas. Technical Area (TA) 55/Plutonium Facility 4 will be used to store the bulk PuO{sub 2} powder, fabricate MOX fuel pellets, assemble rods, and store fuel bundles. Bundles will be assembled at a separate facility, several of which have been identified as suitable for that activity. The Chemistry and Metallurgy Research Building (at TA-3) will be used for analytical chemistry support. Waste operations will be conducted in TA-50 and TA-54. Only very minor modifications will be needed to accommodate the LA program. These modifications consist mostly of minor equipment upgrades. A commercial reactor operator has not been identified for the LA irradiation. Postirradiation examination (PIE) of the irradiated fuel will take place at either Oak Ridge National Laboratory or ANL-W. The only modifications required at either PIE site would be to accommodate full-length irradiated fuel rods. Results from this program are critical to the overall plutonium distribution schedule.

MOX Lead Assembly Fabrication at the Savannah River Site

Energy Technology Data Exchange (ETDEWEB)

Geddes, R.L. [Westinghouse Savannah River Company, AIKEN, SC (United States); Spiker, D.L.; Poon, A.P.

1997-12-01

The U. S. Department of Energy (DOE) announced its intent to prepare an Environmental Impact Statement (EIS) under the National Environmental Policy Act (NEPA) on the disposition of the nations weapon-usable surplus plutonium.This EIS is tiered from the Storage and Disposition of Weapons-Usable Fissile Material Programmatic Environmental Impact Statement issued in December 1996,and the associated Record of Decision issued on January, 1997. The EIS will examine reasonable alternatives and potential environmental impacts for the proposed siting, construction, and operation of three types of facilities for plutonium disposition. The three types of facilities are: a pit disassembly and conversion facility, a facility to immobilize surplus plutonium in a glass or ceramic form for disposition, and a facility to fabricate plutonium oxide into mixed oxide (MOX) fuel.As an integral part of the surplus plutonium program, Oak Ridge National Laboratory (ORNL) was tasked by the DOE Office of Fissile Material Disposition(MD) as the technical lead to organize and evaluate existing facilities in the DOE complex which may meet MD`s need for a domestic MOX fuel fabrication demonstration facility. The Lead Assembly (LA) facility is to produce 1 MT of usable test fuel per year for three years. The Savannah River Site (SRS) as the only operating plutonium processing site in the DOE complex, proposes two options to carry out the fabrication of MOX fuel lead test assemblies: an all Category I facility option and a combined Category I and non-Category I facilities option.

Fuel conditioning facility material accountancy

International Nuclear Information System (INIS)

Yacout, A.M.; Bucher, R.G.; Orechwa, Y.

1995-01-01

The operation of the Fuel conditioning Facility (FCF) is based on the electrometallurgical processing of spent metallic reactor fuel. It differs significantly, therefore, from traditional PUREX process facilities in both processing technology and safeguards implications. For example, the fissile material is processed in FCF only in batches and is transferred within the facility only as solid, well-characterized items; there are no liquid steams containing fissile material within the facility, nor entering or leaving the facility. The analysis of a single batch lends itself also to an analytical relationship between the safeguards criteria, such as alarm limit, detection probability, and maximum significant amount of fissile material, and the accounting system's performance, as it is reflected in the variance associated with the estimate of the inventory difference. This relation, together with the sensitivity of the inventory difference to the uncertainties in the measurements, allows a thorough evaluation of the power of the accounting system. The system for the accountancy of the fissile material in the FCF has two main components: a system to gather and store information during the operation of the facility, and a system to interpret this information with regard to meeting safeguards criteria. These are described and the precision of the inventory closure over one batch evaluated

Separation of silicon carbide-coated fertile and fissile particles by gas classification

International Nuclear Information System (INIS)

Vaughen, V.C.A.

1976-07-01

The separation of 235 U and 233 U in the reprocessing of HTGR fuels is a key feature of the feed-breed fuel cycle concept. This is attained in the Fort St. Vrain (FSV) reactor by coating the fissile (Th- 235 U) particles and the fertile (Th- 233 U) particles separately with silicon carbide (SiC) layers to contain the fission products and to protect the kernels from burning in the head-end reprocessing steps. Pneumatic (gas) classification based on size and density differences is the reference process for separating the SiC-coated particles into fissile and fertile streams for subsequent handling. Terminal velocities have been calculated for the +- 2 sigma ranges of particle sizes and densities for ''Fissile B''--''Fertile A'' particles used in the FSV reactor. Because of overlapping particle fractions, a continuous pneumatic separator appears infeasible; however, a batch separation process can be envisioned. Changing the gas from air to CO 2 and/or the temperature to 300 0 C results in less than 10 percent change in calculated terminal velocities. Recently reported work in gas classification is discussed in light of the theoretical calculations. The pneumatic separation of fissile and fertile particles needs more study, specifically with regard to (1) measuring the recoveries and separation efficiencies of actual fissile and fertile fractions in the tests of the pneumatic classifiers; and (2) improving the contactor design or flowsheet to avoid apparent flow separation or flooding problems at the feed point when using the feed rates required for the pilot plant

HEU to LEU conversion and blending facility: UNH blending alternative to produce LEU oxide for disposal

International Nuclear Information System (INIS)

1995-09-01

The United States Department of Energy (DOE) is examining options for the disposition of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials. Disposition is a process of use or disposal of material that results in the material being converted to a form that is substantially and inherently more proliferation-resistant than is the original form. Examining options for increasing the proliferation resistance of highly enriched uranium (HEU) is part of this effort. This report provides data to be used in the environmental impact analysis for the uranyl nitrate hexahydrate blending option to produce oxide for disposal. This the Conversion and Blending Facility (CBF) alternative will have two missions (1) convert HEU materials into HEU uranyl nitrate (UNH) and (2) blend the HEU uranyl nitrate with depleted and natural assay uranyl nitrate to produce an oxide that can be stored until an acceptable disposal approach is available. The primary emphasis of this blending operation will be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. The blended LEU will be produced as a waste suitable for storage or disposal

HEU to LEU conversion and blending facility: UNH blending alternative to produce LEU oxide for disposal

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

The United States Department of Energy (DOE) is examining options for the disposition of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials. Disposition is a process of use or disposal of material that results in the material being converted to a form that is substantially and inherently more proliferation-resistant than is the original form. Examining options for increasing the proliferation resistance of highly enriched uranium (HEU) is part of this effort. This report provides data to be used in the environmental impact analysis for the uranyl nitrate hexahydrate blending option to produce oxide for disposal. This the Conversion and Blending Facility (CBF) alternative will have two missions (1) convert HEU materials into HEU uranyl nitrate (UNH) and (2) blend the HEU uranyl nitrate with depleted and natural assay uranyl nitrate to produce an oxide that can be stored until an acceptable disposal approach is available. The primary emphasis of this blending operation will be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. The blended LEU will be produced as a waste suitable for storage or disposal.

Multicounter neutron detector for examination of content and spatial distribution of fissile materials in bulk samples

International Nuclear Information System (INIS)

Swiderska-Kowalczyk, M.; Starosta, W.; Zoltowski, T.

1999-01-01

A new neutron coincidence well-counter is presented. This experimental device can be applied for passive assay of fissile and, in particular, for plutonium bearing materials. It contains of a set of the 3 He tubes placed inside a polyethylene moderator. Outputs from the tubes, first processed by preamplifier/amplifier/discriminator circuits, are then analysed using a correlator connected with PC, and correlation techniques implemented in software. Such a neutron counter enables determination of the 240 Pu effective mass in samples of a small Pu content (i.e., where the multiplication effects can be neglected) having a fairly big volume (up to 0.17 m 3 ), if only the isotopic composition is known. For determination of neutron sources distribution inside a sample, a heuristic method based on hierarchical cluster analysis was applied. As input parameters, amplitudes and phases of two-dimensional Fourier transformation of the count profiles matrices for known point sources distributions and for the examined samples were taken. Such matrices of profiles counts are collected using the sample scanning with detection head. In the clustering processes, process, counts profiles of unknown samples are fitted into dendrograms employing the 'proximity' criterion of the examined sample profile to standard samples profiles. Distribution of neutron sources in the examined sample is then evaluated on the basis of a comparison with standard sources distributions. (author)

Calibration measurements using the ORNL fissile mass flow monitor

International Nuclear Information System (INIS)

March-Leuba, J.; Uckan, T.; Sumner, J.; Mattingly, J.; Mihalczo, J.

1998-01-01

This paper presents a demonstration of fissile-mass-flow measurements using the Oak Ridge National Laboratory (ORNL) Fissile Mass Flow Monitor in the Paducah Gaseous Diffusion Plant (PGDP). This Flow Monitor is part of a Blend Down Monitoring System (BDMS) that will be installed in at least two Russian Federation (R.F.) blending facilities. The key objectives of the demonstration of the ORNL Flow Monitor are two: (a) demonstrate that the ORNL Flow Monitor equipment is capable of reliably monitoring the mass flow rate of 235 UF 6 gas, and (b) provide a demonstration of ORNL Flow Monitor system in operation with UF 6 flow for a visiting R.F. delegation. These two objectives have been met by the PGDP demonstration, as presented in this paper

Likely-clean concrete disposition at Chalk River Laboratories

International Nuclear Information System (INIS)

Betts, J.A.

2011-01-01

The vast majority of wastes produced at nuclear licensed sites are no different from wastes produced from other traditional industrial activities. Radiation and contamination control practices ensure that the small amounts of waste materials that contain a radiation and or contamination hazard are segregated and managed appropriately according to the level of hazard. Part of the segregation process involves additional clearance checks of wastes generated in areas where the potential to become radioactively contaminated exists, but is very small and contamination control practices are such that the wastes are believed to be 'likely-clean'. This important clearance step helps to ensure that radioactive contamination is not inadvertently released during disposition of inactive waste materials. Clearance methods for bagged likely-clean wastes (i.e. small volumes of low density wastes) or discreet non-bagged items are well advanced. Clearance of bagged likely-clean wastes involves measuring small volumes of bagged material within purpose built highly sensitive bag monitors. For non-bagged items the outer surfaces are scanned to check for surface contamination using traditional hand-held contamination instrumentation. For certain very bulky and porous materials (such as waste concrete), these traditional clearance methods are impractical or not fully effective. As a somewhat porous (and dense) material, surface scanning cannot always be demonstrated to be conclusive. In order to effectively disposition likely-clean concrete, both the method of clearance (i.e. conversion from likely-clean to clean) and method of disposition have to be considered. Likely-clean concrete wastes have been produced at Chalk River Laboratories (CRL) from demolitions of buildings and structures, as well as small amounts from site maintenance activities. A final disposition method for this material that includes the secondary clearance check that changes the classification of this

Likely-clean concrete disposition at Chalk River Laboratories

Energy Technology Data Exchange (ETDEWEB)

Betts, J.A. [Atomic Energy of Canada Limited, Chalk River, ON (Canada)

2011-07-01

The vast majority of wastes produced at nuclear licensed sites are no different from wastes produced from other traditional industrial activities. Radiation and contamination control practices ensure that the small amounts of waste materials that contain a radiation and or contamination hazard are segregated and managed appropriately according to the level of hazard. Part of the segregation process involves additional clearance checks of wastes generated in areas where the potential to become radioactively contaminated exists, but is very small and contamination control practices are such that the wastes are believed to be 'likely-clean'. This important clearance step helps to ensure that radioactive contamination is not inadvertently released during disposition of inactive waste materials. Clearance methods for bagged likely-clean wastes (i.e. small volumes of low density wastes) or discreet non-bagged items are well advanced. Clearance of bagged likely-clean wastes involves measuring small volumes of bagged material within purpose built highly sensitive bag monitors. For non-bagged items the outer surfaces are scanned to check for surface contamination using traditional hand-held contamination instrumentation. For certain very bulky and porous materials (such as waste concrete), these traditional clearance methods are impractical or not fully effective. As a somewhat porous (and dense) material, surface scanning cannot always be demonstrated to be conclusive. In order to effectively disposition likely-clean concrete, both the method of clearance (i.e. conversion from likely-clean to clean) and method of disposition have to be considered. Likely-clean concrete wastes have been produced at Chalk River Laboratories (CRL) from demolitions of buildings and structures, as well as small amounts from site maintenance activities. A final disposition method for this material that includes the secondary clearance check that changes the classification of this

Fissility of actinide nuclei induced by 60-130 MeV photons

International Nuclear Information System (INIS)

Morcelle, Viviane; Tavares, Odilon A.P.

2004-06-01

Nuclear fissilities obtained from recent photofission reaction cross section measurements carried out at Saskatchewan Accelerator Laboratory (Saskatoon, Canada) in the energy range 60-130 MeV for 232 Th, 233 U, 235 U, 238 U, and 237 Np nuclei have been analysed in a systematic way. To this aim, a semiempirical approach has been developed based on the quasi-deuteron nuclear photoabsorption model followed by the process of competition between neutron evaporation and fission for the excited nucleus. The study reproduces satisfactorily well the increasing trend of nuclear fissility with parameter Z 2 =A. (author)

Local tissue distribution of fissile nuclides

International Nuclear Information System (INIS)

Smith, J.M.

1981-01-01

Conventional tissue-section autoradiography of alpha-emitting actinide elements may require prohibitively long exposure times. Neutron-induced or fission-track autoradiography can be used for fissile nuclides such as 233 U, 235 U, and 239 Pu to circumvent this difficulty. The detection limit for these nuclides is about 4 x 10 -13 (weight fraction). This paper describes a specific technique for determining their microdistribution with histologically stained tissue sections

An approximate method to estimate the minimum critical mass of fissile nuclides

International Nuclear Information System (INIS)

Wright, R.Q.; Jordan, W.C.

1999-01-01

When evaluating systems in criticality safety, it is important to approximate the answer before any analysis is performed. There is currently interest in establishing the minimum critical parameters for fissile actinides. The purpose is to describe the OB-1 method for estimating the minimum critical mass for thermal systems based on one-group calculations and 235 U spheres fully reflected by water. The observation is made that for water-moderated, well-thermalized systems, the transport and leakage from the system are dominated by water. Under these conditions two fissile mixtures will have nearly the same critical volume provided the infinite media multiplication factor (k ∞ ) for the two systems is the same. This observation allows for very simple estimates of critical concentration and mass as a function of the hydrogen-to-fissile (H/X) moderation ratio by comparison to the known 235 U system

Getting the plutonium disposition job done: the concept of a joint-venture disposition enterprise financed by additional sales of highly enriched uranium

International Nuclear Information System (INIS)

Bunn, M.

1996-01-01

The paper gives an outline of a concept which has the potential to provide both substantial financing needed for disposition of plutonium from excess nuclear weapons and the long-term management structure required to implement this effort. The three most important issues were underlined. First, it is urgent to modernize security and accounting systems for all weapon-usable nuclear materials, particularly from former Soviet Union. Second, excess plutonium and Highly Enriched Uranium (HEU) must be brought under international monitoring to ensure irreversibility of nuclear arms reduction. Third, quick move should be done towards actual disposition of excess plutonium and HEU. Technology already exists, but the key issues are how to get finance and manage this operation, particularly given its immense scope and controversial nature. An international joint venture 'Enterprise for nuclear Security' that would build and operate plutonium disposition facilities under stringent non-proliferation controls, financed through additional sales of HEU is a potentially promising approach to addressing the most difficult issues facing the disposition problem

Temperature Profile of the Solution Vessel of an Accelerator-Driven Subcritical Fissile Solution System

Energy Technology Data Exchange (ETDEWEB)

Klein, Steven Karl [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Determan, John C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2015-09-14

Dynamic System Simulation (DSS) models of fissile solution systems have been developed and verified against a variety of historical configurations. DSS techniques have been applied specifically to subcritical accelerator-driven systems using fissile solution fuels of uranium. Initial DSS models were developed in DESIRE, a specialized simulation scripting language. In order to tailor the DSS models to specifically meet needs of system designers they were converted to a Visual Studio implementation, and one of these subsequently to National Instrument’s LabVIEW for human factors engineering and operator training. Specific operational characteristics of subcritical accelerator-driven systems have been examined using a DSS model tailored to this particular class using fissile fuel.

Temperature Profile of the Solution Vessel of an Accelerator-Driven Subcritical Fissile Solution System

International Nuclear Information System (INIS)

Klein, Steven Karl; Determan, John C.

2015-01-01

Dynamic System Simulation (DSS) models of fissile solution systems have been developed and verified against a variety of historical configurations. DSS techniques have been applied specifically to subcritical accelerator-driven systems using fissile solution fuels of uranium. Initial DSS models were developed in DESIRE, a specialized simulation scripting language. In order to tailor the DSS models to specifically meet needs of system designers they were converted to a Visual Studio implementation, and one of these subsequently to National Instrument's LabVIEW for human factors engineering and operator training. Specific operational characteristics of subcritical accelerator-driven systems have been examined using a DSS model tailored to this particular class using fissile fuel.

Americium/Curium Disposition Life Cycle Planning Study

International Nuclear Information System (INIS)

Jackson, W.N.; Krupa, J.; Stutts, P.; Nester, S.; Raimesch, R.

1998-01-01

At the request of the Department of Energy Savannah River Office (DOE- SR), Westinghouse Savannah River Company (WSRC) evaluated concepts to complete disposition of Americium and Curium (Am/Cm) bearing materials currently located at the Savannah River Site (SRS)

Foucaults Dispositive

DEFF Research Database (Denmark)

Raffnsøe, Sverre; Gudmand-Høyer, Marius T.; Thaning, Morten Sørensen

2016-01-01

While Foucault’s work has had a crucial impact on organizational research, the analytical potential of the dispositive has not been sufficiently developed. The purpose of this article is to reconstruct the notion of the dispositive as a key conception in Foucault’s thought, particularly in his...

The burnable poisons utilization for fissile enriched CANDU fuel bundle

Energy Technology Data Exchange (ETDEWEB)

Serghiuta, D; Nainer, O [Team 3 Solutions, Don Mills, ON (Canada)

1996-12-31

Utilization of burnable poison for the fissile enriched fueled CANDU 6 Mk1 core is investigated. The main incentives for this analysis are the reduction of void reactivity effects, the maximization of the fissile content of fresh fuel bundles, and the achievement of better power shape control, in order to preserve the power envelope of the standard 37 rod fuel bundle. The latter allows also the preservation of construction parameters of the standard core (for example: number and location of reactivity devices). It also permits the use of regular shift fueling schemes. The paper makes analyses of MOX weapons-grade plutonium and 1.2% SEU fueled CANDU 6 Mk 1 cores. (author). 6 refs., 4 tabs., 10 figs.

The selection of disposition of precast concrete industrial building

Directory of Open Access Journals (Sweden)

Goleš Danica

2014-01-01

Full Text Available Design of precast concrete industrial building is a complex iterative procedure by which, from a set of known possible solutions, is found the one, that in optimal way meets the set requirements and limitations. By proper selection of the disposition of the building, number of possible solutions is reduced at an early stage of design. This paper presents the main requirements and limitations faced by the structure of precast concrete industrial building, as well as parameters that can be defined in dispositional solution: dimensions, orientation and position of the object, materials, structural system, geometric characteristics, foundation system, the way of decomposition of the structure to prefabricated elements, their bearings and connections, and others. Special emphasis is given to the proper selection of the parameters of disposition in function of set requirements and constraints. The work is intended for graduates and young engineers, to help them to properly systematize and apply the knowledge gained during education, and select the optimal dispositional solution the exact way.

A comparative study between transport and criticality safety indexes for fissile uranium nuclearly pure

Energy Technology Data Exchange (ETDEWEB)

Moraes da Silva, T. de; Sordi, G.M.A.A. [Instituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN (Brazil)]. e-mail: tmsilva@ipen.br

2006-07-01

The international and national standards determine that during the transport of radioactive materials the package to be sent should be identified by labels of risks specifying content, activity and the transport index. The result of the monitoring of the package to 1 meter identifies the transport index, TI, which represents the dose rate to 1 meter of this. The transport index is, by definition, a number that represents a gamma radiation that crosses the superficial layer the radioactive material of the package to 1 meter of distance. For the fissile radioactive material that is the one in which a neutron causes the division of the atom, the international standards specify criticality safety index CSI, which is related with the safe mass of the fissile element. In this work it was determined the respective safe mass for each considered enrichment for the compounds of uranium oxides UO{sub 2}, U{sub 3}O{sub 8} and U{sub 3}Si{sub 2}. In the study of CSI it was observed that the value 50 of the expression 50/N being N the number of packages be transported in subcriticality conditions it represents a fifth part of the safe mass of the element uranium or 9% of the smallest mass critical for a transport not under exclusive use. As conclusion of the accomplished study was observed that the transport index starting from 7% of enrichment doesn't present contribution and that criticality safety index is always greater than the transport index. Therefore what the standards demand to specify, the largest value between both indexes, was clearly identified in this study as being the criticality safety index. (Author)

Safety and regulation aspects of nuclear facilities shutdown

International Nuclear Information System (INIS)

Clement, B.

1977-01-01

Technical dispositions that safety authorities will accept after shutdown of a nuclear installation and reglementation to use are examined. The different solutions from surveillance and maintenance, after removal of fissile materials and radioactive fluids, to dismantling are discussed especially for reactors. In each case the best solution has to be studied to ensure protection of public health and environment [fr

Disposition of excess weapon grade plutonium: Status of the Russian program

Energy Technology Data Exchange (ETDEWEB)

Diyakov, Anatoly [Center for Arms Control, Energy and Environmental Studies, Moscow (Russian Federation)

2015-07-01

During the Cold War, the Soviet Union and United States produced huge quantities of plutonium for weapons. Substantial cuts in their nuclear arsenals released of huge amounts of weapon grade nuclear materials. This put into the agenda the problem what to do with the excess weapon materials. In 2000 Russia and the United States concluded a Plutonium Management and Disposition Agreement (PMDA), committing each to eliminate 34 tons of excess weapon plutonium. It was expected that the implementation of the PMDA Agreement will start in the second half of the year 2009 and the disposition programs finalized in 2025. But from the very beginning the practical implementation of the PMDA agreement met with substantial difficulties. After the consultations held in 2006-2007 the PMDA Agreement was modified. In compliance with the modified Agreement each side pledged to start the disposition of 34 tons of excess plutonium (25 tons in the form of metal and 9 tons in dioxide) in 2018 and to finalize the process in 15 years. Both sides were supposed to use the same disposition method through use in the MOX fuel and its subsequent irradiation in civil nuclear reactors: in light reactors for the USA and in fast neutron reactors for Russia. The presentation is going to provide the current status of the disposition program.

Materials of Criticality Safety Concern in Waste Packages

International Nuclear Information System (INIS)

Larson, S.L.; Day, B.A.

2006-01-01

10 CFR 71.55 requires in part that the fissile material package remain subcritical when considering 'the most reactive credible configuration consistent with the chemical and physical form of the material'. As waste drums and packages may contain unlimited types of materials, determination of the appropriately bounding moderator and reflector materials to ensure compliance with 71.55 requires a comprehensive analysis. Such an analysis was performed to determine the materials or elements that produce the most reactive configuration with regards to both moderation and reflection of a Pu-239 system. The study was originally performed for the TRUPACT-II shipping package and thus the historical fissile mass limit for the package, 325 g Pu-239, was used [1]. Reactivity calculations were performed with the SCALE package to numerically assess the moderation or reflection merits of the materials [2]. Additional details and results are given in SAIC-1322-001 [3]. The development of payload controls utilizing process knowledge to determine the classification of special moderator and/or reflector materials and the associated fissile mass limit is also addressed. (authors)

Characterization of a facility for the measurement of fission fragment transport effects: experimental determination of the fission rates for fissile and fissionable isotopes

International Nuclear Information System (INIS)

Benetti, P.; Raselli, G.L.; Tigliole, A. Borio di; Cagnazzo, M.; Cesana, A.; Mongelli, S.; Terrani, M.

2002-01-01

The transfer facility of the LENA laboratory allows the direct neutron irradiation of fissionable material in the D channel of the TRIGA reactor. A test measurement carried out with a ionization chamber and a 239 Pu sample shows the possibility to use this tool for the study of the transport effects of the fission fragment emerging from thin layers of fissile materials. (author)

Administrative Co-ordination of Fissile Material Management and Accounting in the U.K.A.E.A; Coordination Administrative de la Gestion et de la Comptabilite des Matieres Fissiles dans les Etabussements de l'Autorite de l'Energie Atomique du Royaume-Uni; Administrativnaya koordinatsiya kontrolya i ucheta delyashchikhsya materialov v upravlenii po atomnoj ehnergii soedinennogo korolevstva; Coordinacion Administrativa de la Gestion y la Contabilidad de Materiales Fisionables en la Comision de Energia Atomica del Reino Unido

Energy Technology Data Exchange (ETDEWEB)

Hood, St. C.C. [United Kingdom Atomic Energy Authority, London (United Kingdom)

1966-02-15

The Authority are engaged as suppliers in fissile material production, distribution, recycle and reprocessing. As consumers, the Authority require fissile material for power reactors, a variety of prototypes, MTRs, zero-energy facilities and fuel development projects; and for other experimental and research purposes in laboratory quantities. Executive responsibility for these activities lies with the four Groups through which the Authority discharge these functions. It has been found useful to keep these activities under review in specialized inter-Group Committees, with a common secretariat. These Committees: (a) study all projects all proposals or work involving significant quantities of fissile material (plutonium and enriched uranium, other than natural U or U depleted in {sup 235}U) in the light of expected supplies over a number of years from all sources, including new production, scrap recovery and imports; and all uses including burn-up, losses and exports; (b) recommend the optimum allocation of specific amounts for approved purposes in relation to other calls upon available supplies, and having regard to the economic issues involved; (c) record and progress all approved allocations, and examine the nature, amount and purpose of all existing stockholdings in relation to current policies and objectives; (d) record and study all losses of fissile material during fabrication or other processing and the measures taken to reduce them; (e) assist in developing procedures and incentives to ensure that material is used economically and returned promptly. Each Group has considerable autonomy in its day-to-day use of fissile material. The administrative machinery described above provides a means by which the Authority's scientists, engineers, accountants and administrators concerned with fissile material problems can operate collectively in a common frame of reference with a minimum of paperwork. The paper is illustrated with a simplified flowsheet of the main flows

Revised conceptual designs for the FMDP MOX fresh fuel transport package

International Nuclear Information System (INIS)

Ludwig, S.B.; Michelhaugh, R.D.; Shappert, L.B.; Chae, S.M.; Tang, J.S.

1998-03-01

The revised conceptual designs described in this document provide a foundation for the development and certification of final transport package designs that will be needed to support the disposition of surplus weapons-grade plutonium as mixed-oxide (MOX) fuel in commercial light-water reactors in the US. This document is intended to describe the revised package design concepts and summarize the results of preliminary analyses and assessments of two new concepts for fresh MOX fuel transport packages that have been developed by Oak Ridge National Laboratory during the past year in support of the Department of Energy/Office of Fissile Materials Disposition

A novel method to assay special nuclear materials by measuring prompt neutrons from polarized photofission

Energy Technology Data Exchange (ETDEWEB)

Mueller, J.M., E-mail: mueller@tunl.duke.edu [Triangle Universities Nuclear Laboratory, Durham, NC 27710 (United States); Department of Physics, Duke University, Durham, NC 27708 (United States); Ahmed, M.W. [Triangle Universities Nuclear Laboratory, Durham, NC 27710 (United States); Department of Physics, Duke University, Durham, NC 27708 (United States); Department of Mathematics and Physics, North Carolina Central University, Durham, NC 27707 (United States); Weller, H.R. [Triangle Universities Nuclear Laboratory, Durham, NC 27710 (United States); Department of Physics, Duke University, Durham, NC 27708 (United States)

2014-08-01

A novel method of measuring the enrichment of special nuclear material is presented. Recent photofission measurements using a linearly polarized γ-ray beam were performed on samples of {sup 232}Th, {sup 233,235,238}U, {sup 237}Np, and {sup 239,240}Pu. Prompt neutron polarization asymmetries, defined to be the difference in the prompt neutron yields parallel and perpendicular to the plane of beam polarization divided by their sum, were measured. It was discovered that the prompt neutron polarization asymmetries differed significantly depending on the sample. Prompt neutrons from photofission of even–even (non-fissile) targets had significant polarization asymmetries (∼0.2 to 0.5), while those from odd-A (generally fissile) targets had polarization asymmetries close to zero. This difference in the polarization asymmetries could be exploited to measure the fissile versus non-fissile content of special nuclear materials, and potentially to detect the presence of fissile material during active interrogation. The proposed technique, its expected performance, and its potential applicability are discussed.

A novel method to assay special nuclear materials by measuring prompt neutrons from polarized photofission

International Nuclear Information System (INIS)

Mueller, J.M.; Ahmed, M.W.; Weller, H.R.

2014-01-01

A novel method of measuring the enrichment of special nuclear material is presented. Recent photofission measurements using a linearly polarized γ-ray beam were performed on samples of 232 Th, 233,235,238 U, 237 Np, and 239,240 Pu. Prompt neutron polarization asymmetries, defined to be the difference in the prompt neutron yields parallel and perpendicular to the plane of beam polarization divided by their sum, were measured. It was discovered that the prompt neutron polarization asymmetries differed significantly depending on the sample. Prompt neutrons from photofission of even–even (non-fissile) targets had significant polarization asymmetries (∼0.2 to 0.5), while those from odd-A (generally fissile) targets had polarization asymmetries close to zero. This difference in the polarization asymmetries could be exploited to measure the fissile versus non-fissile content of special nuclear materials, and potentially to detect the presence of fissile material during active interrogation. The proposed technique, its expected performance, and its potential applicability are discussed

Storage and processing system for fissile materials

International Nuclear Information System (INIS)

Bubowskij, B.G.; Bogatyrew, W.K.; Wladykow, G.M.; Swiridenko, W.J.

1976-01-01

The invention concerns the construction of a radiation protection wall by which the reflection of neutrons in a container arranged in the vicinity of the wall is reduced. The radiation protection wall has a coating of neutron-retarding material on top of which there is a layer of neutron absorbing material, the former having a surface structured with regular projections and recesses spaced at 1/8 to 3 neutron ranges. The recesses may be filled with porous material or take up neutron radiation detectors. Other construction features are described. (UWI) [de

Development and production of Zenith fissile elements

Energy Technology Data Exchange (ETDEWEB)

George, D; Wheatley, C C.H.; Lloyd, H

1959-06-15

The development of a new glass-bonded alumina-uranium oxide composition forming the fissile component of the Zenith fuel elements is described, together with the production of the initial charge containing 15 Kg. of U{sub 235]; the composition is capable of retaining fission product gases at high temperatures. The description includes criticality considerations, details of manufacture, and production statistics of the 11,000 discs produced.

The Dispositions Improvement Process

Science.gov (United States)

Brewer, Robin D.; Lindquist, Cynthia; Altemueller, Lisa

2011-01-01

Globally, teacher dispositions along with knowledge and skills continue to be the focal point of teacher education programs. Teachers influence children's development and therefore dispositions are a universal concern. For the past 20 years in the United States, teacher education programs have assessed dispositions. We, however, must now also use…

NDA techniques for spent fuel verification and radiation monitoring. Report on activities 6a and 6b of Task JNT C799 (SAGOR). Finnish support programme to the IAEA safeguards

International Nuclear Information System (INIS)

Tarvainen, M.; Levai, F.; Valentine, T.E.; Abhold, M.; Moran, B.

1997-08-01

A variety of NDA methods exist for measurement of spent fuel at various stages of the disposition process. Each of the methods has weaknesses and strengths that make them applicable to one or more stages in disposition. Both passive and active methods are, under favorable conditions, capable of providing either a mapping of an assembly to identify missing fuel pins or a measurement of the fissile content and some are capable of providing a mapping of a canister to identify missing assemblies or a measurement of the fissile content. However, a spent fuel measurement system capable of making routine partial defect tests of spent fuel assemblies is missing. The active NDA methods, in particular, the active neutron methods, hold the most promise for providing quantitative measurements on fuel assemblies and canisters. Application of NDA methods to shielded casks may not be practical or even possible due to the extent of radiation attenuation by the shielding materials, and none of these methods are considered to have potential for quantitative measurements once the spent fuel cask has been placed in a repository. The most practical approach to spent fuel verification is to confirm the characteristics of the spent fuel prior to loading in a canister or cask at the conditioning facility. Fissile material tracking systems in addition to containment and surveillance methods have the capability to assure continuity of the verified knowledge of the sample from loading of the canisters to final disposal and closing of the repository. (orig.)

Open literature review of threats including sabotage and theft of fissile material transport in Japan

International Nuclear Information System (INIS)

Cochran, John Russell; Furaus, James Phillip; Marincel, Michelle K.

2005-01-01

This report is a review of open literature concerning threats including sabotage and theft related to fissile material transport in Japan. It is intended to aid Japanese officials in the development of a design basis threat. This threat includes the external threats of the terrorist, criminal, and extremist, and the insider threats of the disgruntled employee, the employee forced into cooperation via coercion, the psychotic employee, and the criminal employee. Examination of the external terrorist threat considers Japanese demographics, known terrorist groups in Japan, and the international relations of Japan. Demographically, Japan has a relatively homogenous population, both ethnically and religiously. Japan is a relatively peaceful nation, but its history illustrates that it is not immune to terrorism. It has a history of domestic terrorism and the open literature points to the Red Army, Aum Shinrikyo, Chukaku-Ha, and Seikijuku. Japan supports the United States in its war on terrorism and in Iraq, which may make Japan a target for both international and domestic terrorists. Crime appears to remain low in Japan; however sources note that the foreign crime rate is increasing as the number of foreign nationals in the country increases. Antinuclear groups' recent foci have been nuclear reprocessing technology, transportation of MOX fuel, and possible related nuclear proliferation issues. The insider threat is first defined by the threat of the disgruntled employee. This threat can be determined by studying the history of Japan's employment system, where Keiretsu have provided company stability and lifetime employment. Recent economic difficulties and an increase of corporate crime, due to sole reliability on the honor code, have begun to erode employee loyalty

Apparatus and method for quantitatively evaluating total fissile and total fertile nuclide content in samples

International Nuclear Information System (INIS)

Caldwell, J.T.; Cates, M.R.; Franks, L.A.; Kunz, W.E.

1985-01-01

Simultaneous photon and neutron interrogation of samples for the quantitative determination of total fissile nuclide and total fertile nuclide material present is made possible by the use of an electron accelerator. Prompt and delayed neutrons produced from resulting induced fissions are counted using a single detection system and allow the resolution of the contributions from each interrogating flux leading in turn to the quantitative determination sought. Detection limits for 239 Pu are estimated to be about 3 mg using prompt fission neutrons and about 6 mg using delayed delayed neutrons

Get SMART: the case for a strategic materials reduction treaty, and its implementation

International Nuclear Information System (INIS)

Numark, N.J.

1996-01-01

Inventories of weapons plutonium removed from nuclear warheads should be reduced as quickly as possible to prevent large-scale rearmament by the United States or Russia and to minimize the risk of theft or sabotage by a sub-national group. The U.S. and Russia should agree to a Strategic Materials Reduction Treaty (SMART) establishing an aggressive timetable for manual reduction of national security needs and schedule the final disposition of this material. An aggressive disarmament timetable will require an aggressive implementation program. This should take advantage of available resources within the U.S. and Russia as well as in third countries, including potentially both reactor and immobilization options, as long as stringent safeguards and security can be guaranteed at all participating facilities. Many existing light water reactors in the U.S. are well suited to the purpose, and several private operators of these plants have formally expressed interest to the U.S. government in providing such service. Russian fast and light water reactors appear to be less readily available to burn weapons plutonium. Russia, the United States and other G-7 countries should develop international programs to facilitate the most rapid possible reduction in weapons plutonium inventories, consistent with SMART. Such international co-operation would add credibility and transparency to the nuclear disarmament process in the spirit of the Non-Proliferation Treaty, and could add momentum toward the conclusion of both a Comprehensive Test Ban Treaty and a Fissile Material Production Cut-off Treaty. This international program should take advantage of existing global infrastructure for the use of plutonium fuel as well as other capability (e.g., in the U.S. and Canada) that could supplement existing civilian Pu use plans, as well as vitrification or other immobilization facilities. In combination, it is reasonable to forecast a global capability to disposition at least 10 tons of weapons

Gallium-cladding compatibility testing plan: Phase 3: Test plan for centrally heated surrogate rodlet test. Revision 2

International Nuclear Information System (INIS)

Morris, R.N.; Baldwin, C.A.; Wilson, D.F.

1998-07-01

The Fissile Materials Disposition Program (FMDP) is investigating the use of weapons grade plutonium in mixed oxide (MOX) fuel for light-water reactors (LWR). Commercial MOX fuel has been successfully used in overseas reactors for many years; however, weapons derived fuel may differ from the previous commercial fuels because of small amounts of gallium impurities. A concern presently exists that the gallium may migrate out of the fuel, react with and weaken the clad, and thereby promote loss of fuel pin integrity. Phases 1 and 2 of the gallium task are presently underway to investigate the types of reactions that occur between gallium and clad materials. This is a Level-2 document as defined in the Fissile Materials Disposition Program Light-Water Reactor Mixed-Oxide Fuel Irradiation Test Project Plan. This Plan summarizes the projected Phase 3 Gallium-Cladding compatibility heating test and the follow-on post test examination (PTE). This work will be performed using centrally-heated surrogate pellets, to avoid unnecessary complexities and costs associated with working with plutonium and an irradiation environment. Two sets of rodlets containing pellets prepared by two different methods will be heated. Both sets will have an initial bulk gallium content of approximately 10 ppm. The major emphasis of the PTE task will be to examine the material interactions, particularly indications of gallium transport from the pellets to the clad

Evaluation of Glass Density to Support the Estimation of Fissile Mass Loadings from Iron Concentrations in SB6 Glasses

Energy Technology Data Exchange (ETDEWEB)

Edwards, T.; Peeler, D.

2010-12-15

The Department of Energy - Savannah River (DOE-SR) previously provided direction to Savannah River Remediation (SRR) to maintain fissile concentration in glass below 897 g/m{sup 3}. In support of the guidance, the Savannah River National Laboratory (SRNL) provided a technical basis and a supporting Microsoft{reg_sign} Excel{reg_sign} spreadsheet for the evaluation of fissile loading in Sludge Batch 5 glass based on the Fe concentration in glass as determined by the measurements from the Slurry Mix Evaporator (SME) acceptability analysis. SRR has since requested that SRNL provide the necessary information to allow SRR to update the Excel spreadsheet so that it may be used to maintain fissile concentration in glass below 897 g/m{sup 3} during the processing of Sludge Batch 6 (SB6). One of the primary inputs into the fissile loading spreadsheet includes a bounding density for SB6-based glasses. Based on the measured density data of select SB6 variability study glasses, SRNL recommends that SRR utilize the 99/99 Upper Tolerance Limit (UTL) density value at 38% WL (2.823 g/cm{sup 3}) as a bounding density for SB6 glasses to assess the fissile concentration in this glass system. That is, the 2.823 g/cm{sup 3} is recommended as a key (and fixed) input into the fissile concentration spreadsheet for SB6 processing. It should be noted that no changes are needed to the underlying structure of the Excel based spreadsheet to support fissile assessments for SB6. However, SRR should update the other key inputs to the spreadsheet that are based on fissile and Fe concentrations reported from the SB6 Waste Acceptance Product Specification (WAPS) sample. The purpose of this technical report is to present the density measurements that were determined for the SB6 variability study glasses and to conduct a statistical evaluation of these measurements to provide a bounding density value that may be used as input to the Excel{reg_sign} spreadsheet to be employed by SRR to maintain the

Nuclear fuels technologies fiscal year 1998 research and development test plan

International Nuclear Information System (INIS)

Alberstein, D.; Blair, H.T.; Buksa, J.J.

1998-06-01

A number of research and development (R and D) activities are planned at Los Alamos National Laboratory (LANL) in FY98 in support of the Department of Energy Office of Fissile Materials Disposition (DOE-MD). During the past few years, the ability to fabricate mixed oxide (MOX) nuclear fuel using surplus-weapons plutonium has been researched, and various experiments have been performed. This research effort will be continued in FY98 to support further development of the technology required for MOX fuel fabrication for reactor-based plutonium disposition. R and D activities for FY98 have been divided into four major areas: (1) feed qualification/supply, (2) fuel fabrication development, (3) analytical methods development, and (4) gallium removal. Feed qualification and supply activities encompass those associated with the production of both PuO 2 and UO 2 feed materials. Fuel fabrication development efforts include studies with a new UO 2 feed material, alternate sources of PuO 2 , and determining the effects of gallium on the sintering process. The intent of analytical methods development is to upgrade and improve several analytical measurement techniques in support of other R and D and test fuel fabrication tasks. Finally, the purpose of the gallium removal system activity is to develop and integrate a gallium removal system into the Pit Disassembly and Conversion Facility (PDCF) design and the Phase 2 Advanced Recovery and Integrated Extraction System (ARIES) demonstration line. These four activities will be coordinated and integrated appropriately so that they benefit the Fissile Materials Disposition Program. This plan describes the activities that will occur in FY98 and presents the schedule and milestones for these activities

The ultimate disposition of depleted uranium

Energy Technology Data Exchange (ETDEWEB)

Lemons, T.R. [Uranium Enrichment Organization, Oak Ridge, TN (United States)

1991-12-31

Depleted uranium (DU) is produced as a by-product of the uranium enrichment process. Over 340,000 MTU of DU in the form of UF{sub 6} have been accumulated at the US government gaseous diffusion plants and the stockpile continues to grow. An overview of issues and objectives associated with the inventory management and the ultimate disposition of this material is presented.

Plutonium dioxide dissolution in glass

International Nuclear Information System (INIS)

Vienna, J.D.; Alexander, D.L.; Li, Hong

1996-09-01

In the aftermath of the Cold War, the U.S. Department of Energy's (DOE) Office of Fissile Materials Disposition (OFMD) is charged with providing technical support for evaluation of disposition options for excess fissile materials manufactured for the nation's defense. One option being considered for the disposition of excess plutonium (Pu) is immobilization by vitrification. The vitrification option entails immobilizing Pu in a host glass and waste package that are criticality-safe (immune to nuclear criticality), proliferation-resistant, and environmentally acceptable for long-term storage or disposal. To prove the technical and economic feasibility of candidate vitrification options it is necessary to demonstrate that PuO 2 feedstock can be dissolved in glass in sufficient quantity. The OFMD immobilization program has set a Pu solubility goal of 10 wt% in glass. The life cycle cost of the vitrification options are strongly influenced by the rate at which PUO 2 dissolves in glass. The total number of process lines needed for vitrification of 50 t of Pu in 10 years is directly dependent upon the time required for Pu dissolution in glass. The objective of this joint Pacific Northwest National Laboratory (PNNL) - Savannah River Technology Center (SRTC) study was to demonstrate a high Pu solubility in glass and to identify on a rough scale the time required for Pu dissolution in the glass. This study was conducted using a lanthanide borosilicate (LaBS) glass composition designed at the SRTC for the vitrification of actinides

Plutonium dioxide dissolution in glass

Energy Technology Data Exchange (ETDEWEB)

Vienna, J.D.; Alexander, D.L.; Li, Hong [and others

1996-09-01

In the aftermath of the Cold War, the U.S. Department of Energy`s (DOE) Office of Fissile Materials Disposition (OFMD) is charged with providing technical support for evaluation of disposition options for excess fissile materials manufactured for the nation`s defense. One option being considered for the disposition of excess plutonium (Pu) is immobilization by vitrification. The vitrification option entails immobilizing Pu in a host glass and waste package that are criticality-safe (immune to nuclear criticality), proliferation-resistant, and environmentally acceptable for long-term storage or disposal. To prove the technical and economic feasibility of candidate vitrification options it is necessary to demonstrate that PuO{sub 2} feedstock can be dissolved in glass in sufficient quantity. The OFMD immobilization program has set a Pu solubility goal of 10 wt% in glass. The life cycle cost of the vitrification options are strongly influenced by the rate at which PUO{sub 2} dissolves in glass. The total number of process lines needed for vitrification of 50 t of Pu in 10 years is directly dependent upon the time required for Pu dissolution in glass. The objective of this joint Pacific Northwest National Laboratory (PNNL) - Savannah River Technology Center (SRTC) study was to demonstrate a high Pu solubility in glass and to identify on a rough scale the time required for Pu dissolution in the glass. This study was conducted using a lanthanide borosilicate (LaBS) glass composition designed at the SRTC for the vitrification of actinides.

Multilevel parametrization of fissile nuclei resonance cross sections

International Nuclear Information System (INIS)

Lukyanov, A.A.; Kolesov, V.V.; Janeva, N.

1987-01-01

Because the resonance interference has an important influence on the resonance structure of neutron cross sections energy dependence at lowest energies, multilevel scheme of the cross section parametrization which take into account the resonance interference is used for the description with the same provisions in the regions of the interferential maximum and minimum of the resonance cross sections of the fissile nuclei

Fissile solution dynamics: Student research

Energy Technology Data Exchange (ETDEWEB)

Hetrick, D.L.

1994-09-01

There are two research projects in criticality safety at the University of Arizona: one in dynamic simulation of hypothetical criticality accidents in fissile solutions, and one in criticality benchmarks using transport theory. We have used the data from nuclear excursions in KEWB, CRAC, and SILENE to help in building models for solution excursions. An equation of state for liquids containing gas bubbles has been developed and coupled to point-reactor dynamics in an attempt to predict fission rate, yield, pressure, and kinetic energy. It appears that radiolytic gas is unimportant until after the first peak, but that it does strongly affect the shape of the subsequent power decrease and also the dynamic pressure.

Construction and Demolition Debris 2014 US Final Disposition Estimates Using the CDDPath Method

Data.gov (United States)

U.S. Environmental Protection Agency — Estimates of the final amount and final disposition of materials generated in the Construction and Demolition waste stream measured in total mass of each material....

Development and implementation of attractiveness Level E criteria and the plutonium disposition methodology

International Nuclear Information System (INIS)

Christensen, D.C.; Robinson, M.A.

1998-03-01

Historically, the Department of Energy used the Economic Discard Limits (EDLs), those Special Nuclear Material (SNM) concentrations in residue matrices below which production of new SNM was more economic than SNM recovery, as a basis for discard decisions. In 1994, a joint team from DOE Defense Programs (DP) and Environmental Management (EM) determined that the EDLs were no longer a valid discriminator and directed that SNM disposition consider instead 12 specific criteria, foremost of which are waste minimization, environmental impacts, safety, proliferation concerns, and cost. In response, the Los Alamos National Laboratory developed a technical basis for determining SNM bearing materials unattractive for proliferation purposes and a quantitative method for predicting materials disposition consequences as a basis for decision making called the plutonium disposition methodology. The objective of attractiveness Level E criteria is to insure that waste is unattractive for proliferation or terrorist purposes. Level E criteria is about 0.17 kg Pu per 208 liter drum (requiring diversion of a minimum of 54 drums, assuming 100% recovery efficiency)

Criticality safety margins for mixtures of fissionable materials

International Nuclear Information System (INIS)

Williamson, T.G.; Mincey, J.F.

1992-01-01

In the determination of criticality safety margins, approximations for combinations of fissile and fissionable isotopes are sometimes used that go by names such as the rule of fractions or equivalency relations. Use of the rule of fractions to ensure criticality safety margins was discussed in an earlier paper. The purpose of this paper is to correct errors and to clarify some of the implications. Deviations of safety margins from those calculated by the rule of fractions are still noted; however, the deviations are less severe. Caution in applying such rules is still urged. In general, these approximations are based on American National Standard ANSI/ANS-8.15, Sec. 5.2. This section allows that ratios of material masses to their limits may be summed for fissile nuclides in aqueous solutions. It also allows the addition of nonfissile nuclides if an aqueous moderator is present and addresses the effects of infinite water or equivalent reflector. Water-reflected binary combinations of aqueous solutions of fissile materials, as well as binary combinations of fissile and fissionable metals, were considered. Some combinations were shown to significantly decrease the margin of subcriticality compared to the single-unit margins. In this study, it is confirmed that some combinations of metal units in an optimum geometry may significantly decrease the margin of subcriticality. For some combinations of aqueous solutions of fissile materials, the margin of subcriticality may also be reduced by very small amounts. The conclusion of Ref. 1 that analysts should be careful in applying equivalency relations for combining materials remains valid and sound advice. The ANSI/ANS standard, which allows the use of ratios of masses to their limits, applies to aqueous, fully water-reflected, single-unit solutions. Extensions to other situations should be considered with extreme care

NDA techniques for spent fuel verification and radiation monitoring. Report on activities 6a and 6b of Task JNT C799 (SAGOR). Finnish support programme to the IAEA safeguards

Energy Technology Data Exchange (ETDEWEB)

Tarvainen, M [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland); Levai, F [Technical Univ., Budabest (Hungary); Valentine, T E [Oak Ridge National Lab., TN (United States); Abhold, M [Los Alamos National Lab., NM (United States); Moran, B [USNRC, Washington, DC (United States)

1997-08-01

A variety of NDA methods exist for measurement of spent fuel at various stages of the disposition process. Each of the methods has weaknesses and strengths that make them applicable to one or more stages in disposition. Both passive and active methods are, under favorable conditions, capable of providing either a mapping of an assembly to identify missing fuel pins or a measurement of the fissile content and some are capable of providing a mapping of a canister to identify missing assemblies or a measurement of the fissile content. However, a spent fuel measurement system capable of making routine partial defect tests of spent fuel assemblies is missing. The active NDA methods, in particular, the active neutron methods, hold the most promise for providing quantitative measurements on fuel assemblies and canisters. Application of NDA methods to shielded casks may not be practical or even possible due to the extent of radiation attenuation by the shielding materials, and none of these methods are considered to have potential for quantitative measurements once the spent fuel cask has been placed in a repository. The most practical approach to spent fuel verification is to confirm the characteristics of the spent fuel prior to loading in a canister or cask at the conditioning facility. Fissile material tracking systems in addition to containment and surveillance methods have the capability to assure continuity of the verified knowledge of the sample from loading of the canisters to final disposal and closing of the repository. (orig.). 49 refs.

Partitioning of fissile and radio-toxic materials from spent nuclear fuel

International Nuclear Information System (INIS)

Bychkov, A.V.; Skiba, O.V.; Kormilitsyn, M.V.

2007-01-01

these elements as fuel components, they could be involved in the recycling together with the main actinides, and they could be jointly extracted in the partitioning processes. It is also possible to design some special reactor systems for energy generation. For instance, Np, Am and Cm could be considered as fuel components for fast reactors. It would be possible to apply similar approaches even to the burning of uranium isotopes ( 232,234,236 U), which should be produced in a concentrated form during the re-enrichment. So the future development of innovative technologies should be directed from a complete reprocessing towards partitioning of fissile and radio-toxic materials from the spent nuclear fuel. The objectives of technology optimisation can be stated as follows: (1) reprocessing/partitioning with the view of non-proliferation, (2) partitioning with a minimal effect on the environment (3) partitioning using advanced economical methods. The criteria for the partitioning in future (after the year 2050) can be taken from the INPRO methodology. (authors)

Experience of work with radioactive materials and nuclear fuel at the reactor WWR-K

International Nuclear Information System (INIS)

Maltseva, R.M.; Petukhov, V.K.

1998-01-01

In the report there are considered questions concerning the handling with fresh and spent fuel, experimental devices, containing high enriched uranium, being fissile materials of the bulk form, radioisotopes, obtained in the reactor, and radioactive waste, formed during the operation of the reactor, and organization of storage, account and control of radioactive and fissile materials is described. (author)

Operational Characteristics of an Accelerator Driven Fissile Solution System

International Nuclear Information System (INIS)

Kimpland, Robert Herbert

2016-01-01

Operational characteristics represent the set of responses that a nuclear system exhibits during normal operation. Operators rely on this behavior to assess the status of the system and to predict the consequences of off-normal events. These characteristics largely refer to the relationship between power and system operating conditions. The static and dynamic behavior of a chain-reacting system, operating at sufficient power, is primarily governed by reactivity effects. The science of reactor physics has identified and evaluated a number of such effects, including Doppler broadening and shifts in the thermal neutron spectrum. Often these reactivity effects are quantified in the form of feedback coefficients that serve as coupling coefficients relating the neutron population and the physical mechanisms that drive reactivity effects, such as fissile material temperature and density changes. The operational characteristics of such nuclear systems usually manifest themselves when perturbations between system power (neutron population) and system operating conditions arise. Successful operation of such systems requires the establishment of steady equilibrium conditions. However, prior to obtaining the desired equilibrium (steady-state) conditions, an approach from zero-power (startup) must occur. This operational regime may possess certain limiting system conditions that must be maintained to achieve effective startup. Once steady-state is achieved, a key characteristic of this operational regime is the level of stability that the system possesses. Finally, a third operational regime, shutdown, may also possess limiting conditions of operation that must be maintained. This report documents the operational characteristics of a ''generic'' Accelerator Driven Fissile Solution (ADFS) system during the various operational regimes of startup, steady-state operation, and shutdown. Typical time-dependent behavior for each operational regime will be illustrated, and key system

What is a Dispositive?

DEFF Research Database (Denmark)

Raffnsøe, Sverre; Gudmand-Høyer, Marius T.; Thaning, Morten Sørensen

perspective – indeed it forms a lesser known intermediary between these. Foucault’s dispositional analysis articulates a history of connected social technologies that we have constructed to relate to each other. Expounding these points, the article distinguishes various dispositional prototypes and develops...... key ‘socio-ontological’ implications of the analy-sis. Reinstating the proper analytical status of the dispositive contributes to the reception of the important notion; the interpretation of Foucault’s entire oeuvre; and a resourceful approach to the study of contemporary societal problems....

Disposition of actinides released from high-level waste glass

International Nuclear Information System (INIS)

Ebert, W.L.; Bates, J.K.; Buck, E.C.; Gong, M.; Wolf, S.F.

1994-01-01

A series of static leach tests was conducted using glasses developed for vitrifying tank wastes at the Savannah River Site to monitor the disposition of actinide elements upon corrosion of the glasses. In these tests, glasses produced from SRL 131 and SRL 202 frits were corroded at 90 degrees C in a tuff groundwater. Tests were conducted using crushed glass at different glass surface area-to-solution volume (S/V) ratios to assess the effect of the S/V on the solution chemistry, the corrosion of the glass, and the disposition of actinide elements. Observations regarding the effects of the S/V on the solution chemistry and the corrosion of the glass matrix have been reported previously. This paper highlights the solution analyses performed to assess how the S/V used in a static leach test affects the disposition of actinide elements between fractions that are suspended or dissolved in the solution, and retained by the altered glass or other materials

Test and evaluation of computerized nuclear material accounting methods. Final report

International Nuclear Information System (INIS)

1995-01-01

In accordance with the definition of a Material Balance Area (MBA) as a well-defined geographical area involving an Integral operation, the building housing the BFS-1 and BFS-1 critical facilities is considered to consist of one MBA. The BFS materials are in the form of small disks clad in stainless steel and each disk with nuclear material has its own serial number. Fissile material disks in the BFS MBA can be located at three key monitoring points: BFS-1 facility, BFS-2 facility and main storage of BFS fissile materials (storage 1). When used in the BFS-1 or BFS-2 critical facilities, the fissile material disks are loaded in tubes (fuel rods) forming critical assembly cores. The following specific features of the BFS MBA should be taken into account for the purpose of computerized accounting of nuclear material: (1) very large number of nuclear material items (about 70,000 fissile material items); and (2) periodically very intensive shuffling of nuclear material items. Requirements for the computerized system are determined by basic objectives of nuclear material accounting: (1) providing accurate information on the identity and location of all items in the BFS material balance area; (2) providing accurate information on location and identity of tamper-indicating devices; (3) tracking nuclear material inventories; (4) issuing periodic reports; (5) assisting with the detection of material gains or losses; (6) providing a history of nuclear material transactions; (7) preventing unauthorized access to the system and data falsification. In August 1995, the prototype computerized accounting system was installed on the BFS facility for trial operation. Information on two nuclear material types was entered into the data base: weapon-grade plutonium metal and 36% enriched uranium dioxide. The total number of the weapon-grade plutonium disks is 12,690 and the total number of the uranium dioxide disks is 1,700

Disposal of Surplus Weapons Grade Plutonium

International Nuclear Information System (INIS)

Alsaed, H.; Gottlieb, P.

2000-01-01

The Office of Fissile Materials Disposition is responsible for disposing of inventories of surplus US weapons-usable plutonium and highly enriched uranium as well as providing, technical support for, and ultimate implementation of, efforts to obtain reciprocal disposition of surplus Russian plutonium. On January 4, 2000, the Department of Energy issued a Record of Decision to dispose of up to 50 metric tons of surplus weapons-grade plutonium using two methods. Up to 17 metric tons of surplus plutonium will be immobilized in a ceramic form, placed in cans and embedded in large canisters containing high-level vitrified waste for ultimate disposal in a geologic repository. Approximately 33 metric tons of surplus plutonium will be used to fabricate MOX fuel (mixed oxide fuel, having less than 5% plutonium-239 as the primary fissile material in a uranium-235 carrier matrix). The MOX fuel will be used to produce electricity in existing domestic commercial nuclear reactors. This paper reports the major waste-package-related, long-term disposal impacts of the two waste forms that would be used to accomplish this mission. Particular emphasis is placed on the possibility of criticality. These results are taken from a summary report published earlier this year

1987 target values for uncertainty components in fissile isotope and element assay

International Nuclear Information System (INIS)

De Bievre, P.; Baumann, S.; Gorgenyi, T.; Kuhn, E.; Deron, S.; Dalton, J.; Perrin, R.E.; Pietri, C.; De Regge, P.

1987-01-01

The Working Group on Techniques and Standards for Destructive Analysis (WGDA) of the European Safeguards Research and Development Association (ESARDA), which at present includes the representation of 37 nuclear analytical laboratories, has long been concerned with defining realistic performance characteristics of destructive analysis techniques. One of the terms of reference of the working groups is: ''to evaluate and recommend criteria for destructive analysis of nuclear materials for use by plant operators and safeguarding authorities''. Some of the most important and most badly needed criteria are those to be used for judging results of quantitative determinations of fissile isotope and element amounts. The working group has recognized and discussed this problem at several meetings and decided that it was appropriate to fix reasonable levels of performance as ''goals'' for nuclear analytical laboratories

Computerized real-time materials accountability system for safeguards material control

International Nuclear Information System (INIS)

Spencer, W.F.; Affel, R.G.; Austin, H.C.; Nichols, J.P.; Stoutt, B.H.; Wachter, J.W.

1975-01-01

A real-time, computer-based system is described which provides safeguards material control at the Oak Ridge National Laboratory. Originally installed in 1972 to provide computerized real-time fissile materials accountability for criticality control purposes, the system has been expanded to provide accountability of all source and nuclear materials (SNM) and to utilize the on-line inventory files in support of the Laboratory physical protection and surveillance procedures. (auth)

Remote material handling in the Plutonium Immobilization Project. Revision 1

International Nuclear Information System (INIS)

Brault, J.R.

2000-01-01

With the downsizing of the US and Russian nuclear stockpiles, large quantities of weapons-usable plutonium in the US are being declared excess and will be disposed of by the Department of Energy Fissile Materials Disposition Program. To implement this program, DOE has selected the Savannah River Site (SRS) for the construction and operation of three new facilities: pit disassembly and conversion; mixed oxide fuel fabrication; and plutonium immobilization. The Plutonium Immobilization Project (PIP) will immobilize a portion of the excess plutonium in a hybrid ceramic and glass form containing high level waste for eventual disposal in a geologic repository. The PIP is divided into three distinct operating areas: Plutonium Conversion, First Stage Immobilization, and Second Stage Immobilization. Processing technology for the PIP is being developed jointly by the Lawrence Livermore National Laboratory and Westinghouse Savannah River Company. This paper will discuss development of the automated unpacking and sorting operations in the conversion area, and the automated puck and tray handling operations in the first stage immobilization area. Due to the high radiation levels and toxicity of the materials to be disposed of, the PIP will utilize automated equipment in a contained (glovebox) facility. Most operations involving plutonium-bearing materials will be performed remotely, separating personnel from the radiation source. Source term materials will be removed from the operations during maintenance. Maintenance will then be performed hands on within the containment using glove ports

SRS MOX fuel lead assemblies data report for the surplus plutonium disposition environmental impact statement

International Nuclear Information System (INIS)

O'Connor, D.G.; Fisher, S.E.; Holdaway, R.

1998-08-01

The purpose of this document is to support the US Department of Energy (DOE) Fissile Materials Disposition Program's preparation of the draft surplus plutonium disposition environmental impact statement. This is one of several responses to data call requests for background information on activities associated with the operation of the lead assembly (LA) mixed-oxide (MOX) fuel fabrication facility. DOE-MD requested that the DOE Site Operations Offices nominate DOE sites that meet established minimum requirements that could produce MOX LAs. Six initial site combinations were proposed: (1) Argonne National Laboratory-West (ANL-W) with support from Idaho National Engineering and Environmental Laboratory (INEEL), (2) Hanford, (3) Los Alamos National Laboratory (LANL) with support from Pantex, (4) Lawrence Livermore National Laboratory (LLNL), (5) Oak Ridge Reservation (ORR), and (6) Savannah River Site(SRS). After further analysis by the sites and DOE-MD, five site combinations were established as possible candidates for producing MOX LAs: (1) ANL-W with support from INEEL, (2) Hanford, (3) LANL, (4) LLNL, and (5) SRS. SRS has proposed an LA MOX fuel fabrication approach that would be done entirely inside an S and S Category 1 area. An alternate approach would allow fabrication of fuel pellets and assembly of fuel rods in an S and S Category 2 or 3 facility with storage of bulk PuO 2 and assembly, storage, and shipping of fuel bundles in an S and S Category 1 facility. The total Category 1 approach, which is the recommended option, would be done in the 221-H Canyon Building. A facility that was never in service will be removed from one area, and a hardened wall will be constructed in another area to accommodate execution of the LA fuel fabrication. The non-Category 1 approach would require removal of process equipment in the FB-Line metal production and packaging glove boxes, which requires work in a contamination area. The Immobilization Hot Demonstration Program

SRS MOX fuel lead assemblies data report for the surplus plutonium disposition environmental impact statement

Energy Technology Data Exchange (ETDEWEB)

O`Connor, D.G.; Fisher, S.E.; Holdaway, R. [and others

1998-08-01

The purpose of this document is to support the US Department of Energy (DOE) Fissile Materials Disposition Program`s preparation of the draft surplus plutonium disposition environmental impact statement. This is one of several responses to data call requests for background information on activities associated with the operation of the lead assembly (LA) mixed-oxide (MOX) fuel fabrication facility. DOE-MD requested that the DOE Site Operations Offices nominate DOE sites that meet established minimum requirements that could produce MOX LAs. Six initial site combinations were proposed: (1) Argonne National Laboratory-West (ANL-W) with support from Idaho National Engineering and Environmental Laboratory (INEEL), (2) Hanford, (3) Los Alamos National Laboratory (LANL) with support from Pantex, (4) Lawrence Livermore National Laboratory (LLNL), (5) Oak Ridge Reservation (ORR), and (6) Savannah River Site(SRS). After further analysis by the sites and DOE-MD, five site combinations were established as possible candidates for producing MOX LAs: (1) ANL-W with support from INEEL, (2) Hanford, (3) LANL, (4) LLNL, and (5) SRS. SRS has proposed an LA MOX fuel fabrication approach that would be done entirely inside an S and S Category 1 area. An alternate approach would allow fabrication of fuel pellets and assembly of fuel rods in an S and S Category 2 or 3 facility with storage of bulk PuO{sub 2} and assembly, storage, and shipping of fuel bundles in an S and S Category 1 facility. The total Category 1 approach, which is the recommended option, would be done in the 221-H Canyon Building. A facility that was never in service will be removed from one area, and a hardened wall will be constructed in another area to accommodate execution of the LA fuel fabrication. The non-Category 1 approach would require removal of process equipment in the FB-Line metal production and packaging glove boxes, which requires work in a contamination area. The Immobilization Hot Demonstration Program

Accelerator based production of fissile nuclides, threshold uranium price and perspectives; Akceleratorska proizvodnja fisibilnih nuklida, granicna cijena urana i perspektive

Energy Technology Data Exchange (ETDEWEB)

Djordjevic, D [INIS-Inzenjering, Sarajevo (Yugoslavia); Knapp, V [Elektrotehnicki fakultet, zagreb (Yugoslavia)

1988-07-01

Accelerator breeder system characteristics are considered in this work. One such system which produces fissile nuclides can supply several thermal reactors with fissile fuel, so this system becomes analogous to an uranium enrichment facility with difference that fissile nuclides are produced by conversion of U-238 rather than by separation from natural uranium. This concept, with other long-term perspective for fission technology on the basis of development only one simpler technology. The influence of basic system characteristics on threshold uranium price is examined. Conditions for economically acceptable production are established. (author)

Institute of Nuclear Materials Management 36. annual meeting: Proceedings. Volume 24

International Nuclear Information System (INIS)

Anon.

1995-01-01

The sessions at this meeting covered the following topics: international safeguards; physical protection; material control and accountability (MC and A) training; waste overview; nonproliferation and arms control -- US/former Soviet Union; MC and A/physical protection -- SNM storage; spent fuel storage; physical protection -- intrusion sensors and access delay; MC and A -- gamma ray and holdup measurements; MC and A -- neutron based measurements; MC and A/nonproliferation and arms control -- fissile materials disposition; low level waste; packaging and transportation; international safeguards and nonproliferation and arms control -- IAEA verification in the US; international safeguards and physical protection -- video systems; poster and demonstrations; international safeguards and physical protection -- T.I.D.'s, tags and seals; high level wastes and mixed waste; MC and A -- bulk measurements; MC and A and physical protection -- policy; nonproliferation and arms control -- detection and monitoring techniques; nonproliferation and arms control -- US-Russian lab-to-lab safeguards cooperation; MC and A -- information systems; physical protection and MC and A -- vulnerability assessments; waste management -- measurement; international safeguards -- integrated and remote monitoring systems; MC and A -- material control and accountability and indicators; nonproliferation and arms control -- treaties and analysis; nonproliferation and arms control -- plutonium/HEU nonproliferation; MC and A -- measurement control and verification; and international safeguards and nonproliferation and arms control -- environmental monitoring and export control. Separate abstracts were prepared for some of the papers in this volume

The SVM Method for Fissile Mass Estimation through Passive Neutron Interrogation: Advances and Developments

International Nuclear Information System (INIS)

Dubi, C.; Shvili, Israel I.

2014-01-01

Fissile mass estimation through passive neutron interrogation is now one of the main techniques for NDT of fissile mass estimation, due to the relative transparency of neutron radiation to structural materials- making it extremely effective in poorly characterized or dirty samples . Passive neutron interrogation relies on the fact that the number of neutrons emitted (per time unit) due to spontaneous fissions from the sample is proportional to the mass of the detected sample. However, since the measurement is effected by additional neutron sources- mainly (D±n) reactions and induced fission chain in the tested sample, a naive estimation, assuming a linear correspondence between the mass of the detected sample and the average number of detections, is bound to give an over estimation of the mass. Since most passive interrogation facilities are based on 3He detectors, the origin of the neutron cannot be determined by analyzing the energy spectrum (as all neutrons arrive at the detector in more or less the same energy), and a mathematical 'filter' is used to evaluate the noise to source ratio in the detection signal. The basic idea behind the mathematical filter is to utilize the fact that the different neutron sources have different statistical attributes- in particular, both the source event rate and the distribution of the number of neutrons released in each event differs between the different sources. There for, by studying the higher moments of the neutron population, new information about the source to noise ration may be obtained

Control of radioactive wastes and coupling of neutron/gamma measurements: use of radiative capture for the correction of matrix effects that penalize the fissile mass measurement by active neutron interrogation; Controle des dechets radioactifs et couplage de mesures neutron/gamma: exploitation de la capture radiative pour corriger les effets de matrice penalisant la mesure de la masse fissile par interrogation neutronique active

Energy Technology Data Exchange (ETDEWEB)

Loche, F

2006-10-15

In the framework of radioactive waste drums control, difficulties arise in the nondestructive measurement of fissile mass ({sup 235}U, {sup 239}Pu..) by Active Neutron Interrogation (ANI), when dealing with matrices containing materials (Cl, H...) influencing the neutron flux. The idea is to use the neutron capture reaction (n,{gamma}) to determine the matrix composition to adjust the ANI calibration coefficient value. This study, dealing with 118 litres, homogeneous drums of density less than 0,4 and composed of chlorinated and/or hydrogenated materials, leads to build abacus linking the {gamma} ray peak areas to the ANI calibration coefficient. Validation assays of these abacus show a very good agreement between the corrected and true fissile masses for hydrogenated matrices (max. relative standard deviation: 23 %) and quite good for chlorinated and hydrogenated matrices (58 %). The developed correction method improves the measured values. It may be extended to 0,45 density, heterogeneous drums. (author)

Physics concept on the constellation type fissile fuels and its application to the prospective Th-232U Reactor

International Nuclear Information System (INIS)

Zhang, Jiahua

1994-01-01

In contrast with the conventional nuclear reactor which usually fuelled with on single fissile nuclide, a constellation type fissile fuels reactor consists of a parent nuclide such as 232 Th or 238 U and its whole family of neutron generated daughter nuclides. All of them are regarded as fissile fuels but of quite different fission ability. The concentration of each daughter nuclide is determined by its saturate concentration ratio with the parent nuclide. In such fuel system, the whole fuel consumed by neutron reaction almost completely results in fission products. In this article, some properties of such fuel system, determination of the saturate concentration of each daughter nuclide and applicability to Th- 233 U fueled reactor will be discussed. 3 refs., 1 tab., 2 figs

Russia's atomic tsar: Viktor N. Mikhailov

International Nuclear Information System (INIS)

Reams, C.A.

1996-12-01

Minatom (Ministry of Atomic Energy) was created to manage Russia's nuclear weapons program in the age of disarmament. The ministry is responsible for the development, production, and maintenance of nuclear weapons, warhead dismantlement, the production of nuclear materials for weapons, the disposition of nuclear materials disassembled from warheads, the administration of Russia's vast nuclear weapons complex, the development of policy for the future role of Russia's nuclear complex and payment of employees entrusted with such tasks. Thus, Minatom is instrumental in the implementation of arms control, disarmament and nonproliferation agreements. The director of Minatom, Viktor N. Mikhailov, wields a great deal of power and influence over Russia's nuclear infrastructure. He is an important player amidst efforts to reduce the threats posed by Russia's decaying nuclear complex. There are certainly other personalities in the Russian government who influence Minatom; however, few affect the ministry as profoundly as Mikhailov. His ability to influence Russia's nuclear complex has been clearly demonstrated by his policies in relation to the US purchase of Russian highly enriched uranium, the planned fissile material storage facility at Mayak, materials protection, control and accountability programs, and his unwavering determination to sell Iran commercial nuclear technology. Mikhailov has also been a key negotiator when dealing with the US on issues of transparency of weapons dismantlement and fissile material disposition, as well as the use of US threat reduction funds. His policies and concerns in these areas will affect the prospects for the successful negotiation and implementation of future nuclear threat reduction programs and agreements with Russia

Russia`s atomic tsar: Viktor N. Mikhailov

Energy Technology Data Exchange (ETDEWEB)

Reams, C.A. [Los Alamos National Lab., NM (United States). Center for International Security Affairs

1996-12-01

Minatom (Ministry of Atomic Energy) was created to manage Russia`s nuclear weapons program in the age of disarmament. The ministry is responsible for the development, production, and maintenance of nuclear weapons, warhead dismantlement, the production of nuclear materials for weapons, the disposition of nuclear materials disassembled from warheads, the administration of Russia`s vast nuclear weapons complex, the development of policy for the future role of Russia`s nuclear complex and payment of employees entrusted with such tasks. Thus, Minatom is instrumental in the implementation of arms control, disarmament and nonproliferation agreements. The director of Minatom, Viktor N. Mikhailov, wields a great deal of power and influence over Russia`s nuclear infrastructure. He is an important player amidst efforts to reduce the threats posed by Russia`s decaying nuclear complex. There are certainly other personalities in the Russian government who influence Minatom; however, few affect the ministry as profoundly as Mikhailov. His ability to influence Russia`s nuclear complex has been clearly demonstrated by his policies in relation to the US purchase of Russian highly enriched uranium, the planned fissile material storage facility at Mayak, materials protection, control and accountability programs, and his unwavering determination to sell Iran commercial nuclear technology. Mikhailov has also been a key negotiator when dealing with the US on issues of transparency of weapons dismantlement and fissile material disposition, as well as the use of US threat reduction funds. His policies and concerns in these areas will affect the prospects for the successful negotiation and implementation of future nuclear threat reduction programs and agreements with Russia.

Options for the disposition of current inventory of Rocky Flats Plant residues

International Nuclear Information System (INIS)

Chang, Lychin.

1994-01-01

With the end of the Cold War, much concern has been directed towards the accumulation of special nuclear material resulting from the dismantlement of a large number of nuclear weapons. This concern has opened up a debate over the final disposition of the large inventory of weapons-capable plutonium. Technologies for the conversion of plutonium into acceptable forms will need to be assessed and evaluated. Candidate strategies for interim and final disposition include a variety of immobilization techniques (vitrification in glass, ceramic, or metal), conversion to reactor fuel, or direct discard as waste. The selected disposition strategy will be chosen based upon a range of decision metric such as expected conversion costs, equipment requirements, and waste generation. To this end, a systems analysis approach is necessary for the evaluation and comparison of the different disposition strategies. Current data on inventory of plutonium, such as that at the Rocky Flats Plant (RFP), may be useful for the evaluation and selection of candidate disposition technologies. A preliminary analysis of the residues of scrap at Rocky Flats was performed to establish a foundation for comparison of candidate strategies. About 3 metric tons of plutonium and 270 metric tons of other wastes remain in the inventory at Rocky Flats. Estimates on the equipment, facility, manpower, and cost requirements to process this inventory over a proposed 10-year cleanup campaign will provide a benchmark for comparison and assessment of proposed disposition technologies

Ultimate disposition of aluminum clad spent nuclear fuel in the United States

International Nuclear Information System (INIS)

Messick, C.E.; Clark, W.D.; Clapper, M.; Mustin, T.P.

2001-01-01

Treatment and disposition of spent nuclear fuel (SNF) in the United States has changed significantly over the last decade due to change in world climate associated with nuclear material. Chemical processing of aluminum based SNF is ending and alternate disposition paths are being developed that will allow for the ultimate disposition of the enriched uranium in this SNF. Existing inventories of aluminum based SNF are currently being stored primarily in water-filled basins at the Savannah River Site (SRS) while these alternate disposition paths are being developed and implemented. Nuclear nonproliferation continues to be a worldwide concern and it is causing a significant influence on the development of management alternatives for SNF. SRS recently completed an environmental impact statement for the management of aluminum clad SNF that selects alternatives for all of the fuels in inventory. The U.S. Department of Energy and SRS are now implementing a dual strategy of processing small quantities of 'problematic' SNF while developing an alternative technology to dispose of the remaining aluminum clad SNF in the proposed monitored geologic repository. (author)

Gallium-cladding compatibility testing plan. Phases 1 and 2: Test plan for gallium corrosion tests. Revision 2

International Nuclear Information System (INIS)

Wilson, D.F.; Morris, R.N.

1998-05-01

This test plan is a Level-2 document as defined in the Fissile Materials Disposition Program Light-Water-Reactor Mixed-Oxide Fuel Irradiation Test Project Plan. The plan summarizes and updates the projected Phases 1 and 2 Gallium-Cladding compatibility corrosion testing and the following post-test examination. This work will characterize the reactions and changes, if any, in mechanical properties that occur between Zircaloy clad and gallium or gallium oxide in the temperature range 30--700 C

Life Cycle Analysis for D and D Decision Making: Disposition of Hanford Railcars

Energy Technology Data Exchange (ETDEWEB)

Yuracko, K.L.

2001-01-11

This report summarizes a joint venture between the U.S. Department of Energy (DOE) Deactivation and Decommissioning Focus Area and the Oak Ridge Operations Assets Utilization (AU) Facilities and Materials Reuse Division (FMRD) in its role as the DOE National Center of Excellence for Metals Recycle (NMR), to better address problems in the DOE complex. This task was initially developed to meet a request from the Richland Operations Office (RL) to AU FMRD for assistance in analyzing equipment reuse and metals recycling opportunities at RL, utilizing expertise and experience related to life cycle analysis (LCA), technology, and planning. Oak Ridge National Laboratory (ORNL) has developed an LCA system to assist DOE in identifying and analyzing opportunities for equipment and materials reuse and recycle. This report presents the use of the LCA system to identify and analyze methods for disposition of surplus railcars at the Hanford site. Alternative possible disposition pathways were evaluated for their financial, health and safety, environmental, programmatic, and institutional impacts; and a preferred disposition pathway was identified.

Control of radioactive wastes and coupling of neutron/gamma measurements: use of radiative capture for the correction of matrix effects that penalize the fissile mass measurement by active neutron interrogation

International Nuclear Information System (INIS)

Loche, F.

2006-10-01

In the framework of radioactive waste drums control, difficulties arise in the nondestructive measurement of fissile mass ( 235 U, 239 Pu..) by Active Neutron Interrogation (ANI), when dealing with matrices containing materials (Cl, H...) influencing the neutron flux. The idea is to use the neutron capture reaction (n,γ) to determine the matrix composition to adjust the ANI calibration coefficient value. This study, dealing with 118 litres, homogeneous drums of density less than 0,4 and composed of chlorinated and/or hydrogenated materials, leads to build abacus linking the γ ray peak areas to the ANI calibration coefficient. Validation assays of these abacus show a very good agreement between the corrected and true fissile masses for hydrogenated matrices (max. relative standard deviation: 23 %) and quite good for chlorinated and hydrogenated matrices (58 %). The developed correction method improves the measured values. It may be extended to 0,45 density, heterogeneous drums. (author)

NRC comprehensive records disposition schedule

International Nuclear Information System (INIS)

1992-03-01

Title 44 United States Code, ''Public Printing and Documents,'' regulations cited in the General Services Administration's (GSA) ''Federal Information Resources Management Regulations'' (FIRMR), Part 201-9, ''Creation, Maintenance, and Use of Records,'' and regulation issued by the National Archives and Records Administration (NARA) in 36 CFR Chapter XII, Subchapter B, ''Records Management,'' require each agency to prepare and issue a comprehensive records disposition schedule that contains the NARA approved records disposition schedules for records unique to the agency and contains the NARA's General Records Schedules for records common to several or all agencies. The approved records disposition schedules specify the appropriate duration of retention and the final disposition for records created or maintained by the NRC. NUREG-0910, Rev. 2, contains ''NRC's Comprehensive Records Disposition Schedule,'' and the original authorized approved citation numbers issued by NARA. Rev. 2 totally reorganizes the records schedules from a functional arrangement to an arrangement by the host office. A subject index and a conversion table have also been developed for the NRC schedules to allow staff to identify the new schedule numbers easily and to improve their ability to locate applicable schedules

Calculation of the minimum critical mass of fissile nuclides

International Nuclear Information System (INIS)

Wright, R.Q.; Hopper, Calvin Mitchell

2008-01-01

The OB-1 method for the calculation of the minimum critical mass of fissile actinides in metal/water systems was described in a previous paper. A fit to the calculated minimum critical mass data using the extended criticality parameter is the basis of the revised method. The solution density (grams/liter) for the minimum critical mass is also obtained by a fit to calculated values. Input to the calculation consists of the Maxwellian averaged fission and absorption cross sections and the thermal values of nubar. The revised method gives more accurate values than the original method does for both the minimum critical mass and the solution densities. The OB-1 method has been extended to calculate the uncertainties in the minimum critical mass for 12 different fissile nuclides. The uncertainties for the fission and capture cross sections and the estimated nubar uncertainties are used to determine the uncertainties in the minimum critical mass, either in percent or grams. Results have been obtained for U-233, U-235, Pu-236, Pu-239, Pu-241, Am-242m, Cm-243, Cm-245, Cf-249, Cf-251, Cf-253, and Es-254. Eight of these 12 nuclides are included in the ANS-8.15 standard.

Measurement techniques for the verification of excess weapons materials

International Nuclear Information System (INIS)

Tape, J.W.; Eccleston, G.W.; Yates, M.A.

1998-01-01

The end of the superpower arms race has resulted in an unprecedented reduction in stockpiles of deployed nuclear weapons. Numerous proposals have been put forward and actions have been taken to ensure the irreversibility of nuclear arms reductions, including unilateral initiatives such as those made by President Clinton in September 1993 to place fissile materials no longer needed for a deterrent under international inspection, and bilateral and multilateral measures currently being negotiated. For the technologist, there is a unique opportunity to develop the technical means to monitor nuclear materials that have been declared excess to nuclear weapons programs, to provide confidence that reductions are taking place and that the released materials are not being used again for nuclear explosive programs. However, because of the sensitive nature of these materials, a fundamental conflict exists between the desire to know that the bulk materials or weapon components in fact represent evidence of warhead reductions, and treaty commitments and national laws that require the protection of weapons design information. This conflict presents a unique challenge to technologists. The flow of excess weapons materials, from deployed warheads through storage, disassembly, component storage, conversion to bulk forms, and disposition, will be described in general terms. Measurement approaches based on the detection of passive or induced radiation will be discussed along with the requirement to protect sensitive information from release to unauthorized parties. Possible uses of measurement methods to assist in the verification of arms reductions will be described. The concept of measuring attributes of items rather than quantitative mass-based inventory verification will be discussed along with associated information-barrier concepts required to protect sensitive information

Plutonium disposition via immobilization in ceramic or glass

Energy Technology Data Exchange (ETDEWEB)

Gray, L.W.; Kan, T.; Shaw, H.F.; Armantrout, A.

1997-03-05

The management of surplus weapons plutonium is an important and urgent task with profound environmental, national, and international security implications. In the aftermath of the Cold War, Presidential Policy Directive 13, and various analyses by renown scientific, technical, and international policy organizations have brought about a focused effort within the Department of Energy to identify and implement paths for the long term disposition of surplus weapons- usable plutonium. The central goal of this effort is to render surplus weapons plutonium as inaccessible and unattractive for reuse in nuclear weapons as the much larger and growing stock of plutonium contained in spent fuel from civilian reactors. One disposition option being considered for surplus plutonium is immobilization, in which the plutonium would be incorporated into a glass or ceramic material that would ultimately be entombed permanently in a geologic repository for high-level waste.

Alternative repository criticality-control strategies for fissile uranium wastes

International Nuclear Information System (INIS)

Forsberg, C.W.

1998-01-01

Methods to prevent long term, disposal site nuclear criticality from fissile uranium isotopes in wastes were investigated. Long term refers to the time period after waste package (WP) failure and the subsequent loss of geometry and chemistry control within the WP. The preferred method of control was found to be the addition of sufficient depleted uranium to each WP so that the uranium enrichment is reduced to 235 U and 233 U in 238 U

Covariance Spectroscopy for Fissile Material Detection

International Nuclear Information System (INIS)

Trainham, Rusty; Tinsley, Jim; Hurley, Paul; Keegan, Ray

2009-01-01

Nuclear fission produces multiple prompt neutrons and gammas at each fission event. The resulting daughter nuclei continue to emit delayed radiation as neutrons boil off, beta decay occurs, etc. All of the radiations are causally connected, and therefore correlated. The correlations are generally positive, but when different decay channels compete, so that some radiations tend to exclude others, negative correlations could also be observed. A similar problem of reduced complexity is that of cascades radiation, whereby a simple radioactive decay produces two or more correlated gamma rays at each decay. Covariance is the usual means for measuring correlation, and techniques of covariance mapping may be useful to produce distinct signatures of special nuclear materials (SNM). A covariance measurement can also be used to filter data streams because uncorrelated signals are largely rejected. The technique is generally more effective than a coincidence measurement. In this poster, we concentrate on cascades and the covariance filtering problem

Chemicals and excess materials disposition during deactivation as a means of pollution prevention

International Nuclear Information System (INIS)

Godfrey, S.D.

1998-01-01

This paper presents several innovative and common sense approaches to pollution prevention that have been employed during facility deactivation at the Hanford Site in South Central Washington. It also presents several pollution prevention principles applicable to other projects. Innovative pollution prevention ideas employed at the Hanford site during facility deactivation included: (1) Recycling more than 185,000 gallons of radioactively contaminated nitric acid by sending it to an operating nuclear fuels reprocessing facility in England; (2) Recycling millions of pounds of chemicals and excess materials to other industries for reuse; (3) Evaporating flush water at a low rate and discharging it into the facility exhaust air stream to avoid discharging thousands of gallons of liquid to the soil column; and (4) Decontaminating and disposing of thousands of gallons of radioactively contaminated organic solvent waste to a RCRA licensed, power-producing, commercial incinerator. Common sense pollution prevention ideas that were employed include recycling office furniture, recycling paper from office files, and redeploying tools and miscellaneous process equipment. Additional pollution prevention occurred as the facility liquid and gaseous discharge streams were deactivated. From the facilities deactivation experiences at Hanford and the ensuing efforts to disposition excess chemicals and materials, several key pollution prevention principles should be considered at other projects and facilities, especially during the operational periods of the facility's mission. These principles include: Institute pollution prevention as a fundamental requirement early in the planning stage of a project or during the operational phase of a facility's mission; Promote recognition and implementation of pollution prevention initiatives; Instill pollution prevention as a value in all participants in the project or facility work scope; Minimize the amount of chemical products and materials

Development of AGNES, a kinetics code for fissile solutions, 1

International Nuclear Information System (INIS)

Nakajima, Ken; Ohnishi, Nobuaki

1986-01-01

A kinetics code for fissile solutions, AGNES (Accidentally Generated Nuclear Excursion Simulation code), has been developed. This code calculates the radiolytic gas void effect as a reactivity feedback. Physical and calculative models of the radiolytic gas void are summarized and the usage of AGNES is described. In addition, some benchmark calculations were performed and results of calculations show good agreement with those of experiments. (author)

Dispositional greed.

Science.gov (United States)

Seuntjens, Terri G; Zeelenberg, Marcel; van de Ven, Niels; Breugelmans, Seger M

2015-06-01

Greed is an important motive: it is seen as both productive (a source of ambition; the motor of the economy) and destructive (undermining social relationships; the cause of the late 2000s financial crisis). However, relatively little is known about what greed is and does. This article reports on 5 studies that develop and test the 7-item Dispositional Greed Scale (DGS). Study 1 (including 4 separate samples from 2 different countries, total N = 6092) provides evidence for the construct and discriminant validity of the DGS in terms of positive correlations with maximization, self-interest, envy, materialism, and impulsiveness, and negative correlations with self-control and life satisfaction. Study 2 (N = 290) presents further evidence for discriminant validity, finding that the DGS predicts greedy behavioral tendencies over and above materialism. Furthermore, the DGS predicts economic behavior: greedy people allocate more money to themselves in dictator games (Study 3, N = 300) and ultimatum games (Study 4, N = 603), and take more in a resource dilemma (Study 5, N = 305). These findings shed light on what greed is and does, how people differ in greed, and how greed can be measured. In addition, they show the importance of greed in economic behavior and provide directions for future studies. (c) 2015 APA, all rights reserved).

The Optimum Plutonium Inert Matrix Fuel Form for Reactor-Based Plutonium Disposition

International Nuclear Information System (INIS)

Tulenko, J.S.; Wang, J.; Acosta, C.

2004-01-01

The University of Florida has underway an ongoing research program to validate the economic, operational and performance benefits of developing an inert matrix fuel (IMF) for the disposition of the U.S. weapons plutonium (Pu) and for the recycle of reprocessed Pu. The current fuel form of choice for Pu disposition for the Department of Energy is as a mixed oxide (MOX) (PuO2/UO2). We will show analyses that demonstrate that a Silicon Carbide (SiC) IMF offers improved performance capabilities as a fuel form for Pu recycle and disposition. The reason that UF is reviewing various materials to serve as an inert matrix fuel is that an IMF fuel form can offer greatly reduced Pu and transuranic isotope (TRU) production and also improved thermal performance characteristics. Our studies showed that the Pu content is reduced by an order of magnitude while centerline fuel temperatures are reduced approximately 380 degrees centigrade compared to MOX. These reduced temperatures result in reduced stored heat and thermal stresses in the pellet. The reduced stored heat reduces the consequences of the loss of coolant accident, while the reduced temperatures and thermal stresses yield greatly improved fuel performance. Silicon Carbide is not new to the nuclear industry, being a basic fuel material in gas cooled reactors

Light water reactor mixed-oxide fuel irradiation experiment

International Nuclear Information System (INIS)

Hodge, S.A.; Cowell, B.S.; Chang, G.S.; Ryskamp, J.M.

1998-01-01

The United States Department of Energy Office of Fissile Materials Disposition is sponsoring and Oak Ridge National Laboratory (ORNL) is leading an irradiation experiment to test mixed uranium-plutonium oxide (MOX) fuel made from weapons-grade (WG) plutonium. In this multiyear program, sealed capsules containing MOX fuel pellets fabricated at Los Alamos National Laboratory (LANL) are being irradiated in the Advanced Test Reactor (ATR) at the Idaho National Engineering and Environmental Laboratory (INEEL). The planned experiments will investigate the utilization of dry-processed plutonium, the effects of WG plutonium isotopics on MOX performance, and any material interactions of gallium with Zircaloy cladding

Identification of High-Z Materials With Photoneutrons Driven by a Low-Energy Electron Linear Accelerator

Science.gov (United States)

Yang, Yigang; Zhang, Zhi; Chen, Huaibi; Li, Yulan; Li, Yuanjing

2017-07-01

Contraband-detection systems can use X-rays and photoneutrons delivered from the same 7-MeV electron linear accelerator (e-LINAC) to stimulate and extract information from inspected materials. The X-ray attenuation information is used to measure the mass thickness, which is combined with the photoneutron attenuation information to categorize inspected materials as common organic materials, metals, and heavy metals. Once a heavy metal is found, the beta-delayed neutrons stimulated by the (γ,fission) reaction are measured by a polyethylene-moderated 3He counter to clarify if the material is fissile. The presence of neutron events 2000 μs after the X-ray pulse confirms the existence of the fissile material. The isotopes in the material are then identified using the time-of-flight method to analyze the resonant attenuation of the fissile material to the 10-1-102 eV photoneutrons emitted from and thermalized by the D2O photonto-neutron convertor, which converts X-rays to photoneutrons. Eight high-Z simulants are tested to confirm the feasibility of identifying the isotopes from the photoneutron resonance. The underlying principles and experimental results are discussed.

Status of radioactive material transport

International Nuclear Information System (INIS)

Kueny, Laurent

2012-01-01

As about 900.000 parcels containing radioactive materials are transported every year in France, the author recalls the main risks and safety principles associated with such transport. He indicates the different types of parcels defined by the regulation: excepted parcels, industrial non fissile parcels (type A), type B and fissile parcels, and highly radioactive type C parcels. He briefly presents the Q-system which is used to classify the parcels. He describes the role of the ASN in the control of transport safety, and indicates the different contracts existing between France or Areva and different countries (Germany, Japan, Netherlands, etc.) for the processing of used fuels in La Hague

Nuclear Materials Stewardship Within the DOE Environmental Management Program

International Nuclear Information System (INIS)

Bilyeu, J. D.; Kiess, T. E.; Gates, M. L.

2002-01-01

The Department of Energy (DOE) Environmental Management (EM) Program has made significant progress in planning disposition of its excess nuclear materials and has recently completed several noteworthy studies. Since establishment in 1997, the EM Nuclear Material Stewardship Program has developed disposition plans for excess nuclear materials to support facility deactivation. All nuclear materials have been removed from the Miamisburg Environmental Management Project (Mound), and disposition planning is nearing completion for the Fernald Environmental Management Project and the Rocky Flats Environmental Technology Site. Only a few issues remain for materials at the Hanford and Idaho sites. Recent trade studies include the Savannah River Site Canyons Nuclear Materials Identification Study, a Cesium/Strontium Management Alternatives Trade Study, a Liquid Technical Standards Trade Study, an Irradiated Beryllium Reflectors with Tritium study, a Special Performance Assessment Required Trade Study, a Neutron Source Trade Study, and development of discard criteria for uranium. A Small Sites Workshop was also held. Potential and planned future activities include updating the Plutonium-239 storage study, developing additional packaging standards, developing a Nuclear Material Disposition Handbook, determining how to recover or dispose of Pu-244 and U-233, and working with additional sites to define disposition plans for their nuclear materials

Method for ultimate disposition of borate containing radioactive wastes by vitrification

International Nuclear Information System (INIS)

Bege, D.; Faust, H.J.; Puthawala, A.; Stunkel, H.

1984-01-01

Method for the ultimate disposition of radioactive wastes by vitrification, in which weak to medium radioactive waste concentrates from borate-containing radioactive liquids are mixed with added glass-forming materials, maximally in a ratio of 1:3, and the mixture heated to obtain a glass-forming melt

Options for the disposition of current inventory of Rocky Flats Plant residues. Revision 1

International Nuclear Information System (INIS)

Chang, L.

1994-01-01

With the end of the Cold War, much concern has been directed towards the accumulation of special nuclear material resulting from the dismantlement of a large number of nuclear weapons. This concern has opened up a debate over the final disposition of the large inventory of weapons-capable plutonium. Technologies for the conversion of plutonium into acceptable forms will need to be assessed and evaluated. Candidate strategies for interim and final disposition include a variety of immobilization techniques (vitrification in glass, ceramic, or metal), conversion to reactor fuel, or direct discard as waste. The selected disposition strategy will be chosen based upon a range of decision metrics such as expected conversion costs, equipment requirements, and waste generation. To this end, a systems analysis approach is necessary for the evaluation and comparison of the different disposition strategies. Current data on inventory of plutonium, such as that at the Rocky Flats Plant (RFP), may be useful for the evaluation and selection of candidate disposition technologies. A preliminary analysis of the residues of scrap at Rocky Flats was performed to establish a foundation for comparison of candidate strategies. About 3 metric tons of plutonium and 270 metric tons of other wastes remain in the inventory at Rocky Flats. Estimates on the equipment, facility, manpower, and cost requirements to process this inventory over a proposed 10-year cleanup campaign will provide a benchmark for comparison and assessment of proposed disposition technologies

The regulation concerning transportation of radioactive materials by vehicles

International Nuclear Information System (INIS)

1978-01-01

The Regulation is established on the basis of The law for the regulations of nuclear source materials, nuclear fuel materials and reactors'' and the ''Law for the prevention of radiation injuries due to radioisotopes.'' The prescriptions cover the transport of radioactive materials by railway, street rail way, ropeway, trolley buses, motorcars and light vehicles. Terms are explained, such as nuclear fuel materials, radioisotopes, radioactive substances, transported radioactive things, transported fissile things, vehicles, containers, exclusive loading, surrounding inspection area. Four types of transported radioactive things are specified, L and A types being less dangerous and BM and BU being more dangerous. Transported fissile things are classified to three kinds according to the safety to criticality of such things. Transported radioactive things except those of L type and containers with transported fissile things shall not be loaded or unloaded at the places where persons other than those concerned come in usually. Loading and unloading of such things shall be carried out so that the safety of such things is not injured. The maximum dose rate of radiation of the containers with transported radioactive things shall not be more than 200 millirem per hour on the surface and 10 millirem per hour at the distance of 1 meter. Specified transported radioactive things shall be particularly marked by the letter of ''radioactive'' or other signs indicating as such. (Okada, K.)

Weapons-grade plutonium dispositioning. Volume 2: Comparison of plutonium disposition options

International Nuclear Information System (INIS)

Brownson, D.A.; Hanson, D.J.; Blackman, H.S.

1993-06-01

The Secretary of Energy requested the National Academy of Sciences (NAS) Committee on International Security and Arms Control to evaluate disposition options for weapons-grade plutonium. The Idaho National Engineering Laboratory (INEL) offered to assist the NAS in this evaluation by investigating the technical aspects of the disposition options and their capability for achieving plutonium annihilation levels greater than 90%. This report was prepared for the NAS to document the gathered information and results from the requested option evaluations. Evaluations were performed for 12 plutonium disposition options involving five reactor and one accelerator-based systems. Each option was evaluated in four technical areas: (1) fuel status, (2) reactor or accelerator-based system status, (3) waste-processing status, and (4) waste disposal status. Based on these evaluations, each concept was rated on its operational capability and time to deployment. A third rating category of option costs could not be performed because of the unavailability of adequate information from the concept sponsors. The four options achieving the highest rating, in alphabetical order, are the Advanced Light Water Reactor with plutonium-based ternary fuel, the Advanced Liquid Metal Reactor with plutonium-based fuel, the Advanced Liquid Metal Reactor with uranium-plutonium-based fuel, and the Modular High Temperature Gas-Cooled Reactor with plutonium-based fuel. Of these four options, the Advanced Light Water Reactor and the Modular High Temperature Gas-Cooled Reactor do not propose reprocessing of their irradiated fuel. Time constraints and lack of detailed information did not allow for any further ratings among these four options. The INEL recommends these four options be investigated further to determine the optimum reactor design for plutonium disposition

Weapons-grade plutonium dispositioning. Volume 2: Comparison of plutonium disposition options

Energy Technology Data Exchange (ETDEWEB)

Brownson, D.A.; Hanson, D.J.; Blackman, H.S. [and others

1993-06-01

The Secretary of Energy requested the National Academy of Sciences (NAS) Committee on International Security and Arms Control to evaluate disposition options for weapons-grade plutonium. The Idaho National Engineering Laboratory (INEL) offered to assist the NAS in this evaluation by investigating the technical aspects of the disposition options and their capability for achieving plutonium annihilation levels greater than 90%. This report was prepared for the NAS to document the gathered information and results from the requested option evaluations. Evaluations were performed for 12 plutonium disposition options involving five reactor and one accelerator-based systems. Each option was evaluated in four technical areas: (1) fuel status, (2) reactor or accelerator-based system status, (3) waste-processing status, and (4) waste disposal status. Based on these evaluations, each concept was rated on its operational capability and time to deployment. A third rating category of option costs could not be performed because of the unavailability of adequate information from the concept sponsors. The four options achieving the highest rating, in alphabetical order, are the Advanced Light Water Reactor with plutonium-based ternary fuel, the Advanced Liquid Metal Reactor with plutonium-based fuel, the Advanced Liquid Metal Reactor with uranium-plutonium-based fuel, and the Modular High Temperature Gas-Cooled Reactor with plutonium-based fuel. Of these four options, the Advanced Light Water Reactor and the Modular High Temperature Gas-Cooled Reactor do not propose reprocessing of their irradiated fuel. Time constraints and lack of detailed information did not allow for any further ratings among these four options. The INEL recommends these four options be investigated further to determine the optimum reactor design for plutonium disposition.

The ultimate disposition of depleted uranium

Energy Technology Data Exchange (ETDEWEB)

1990-12-01

Significant amounts of the depleted uranium (DU) created by past uranium enrichment activities have been sold, disposed of commercially, or utilized by defense programs. In recent years, however, the demand for DU has become quite small compared to quantities available, and within the US Department of Energy (DOE) there is concern for any risks and/or cost liabilities that might be associated with the ever-growing inventory of this material. As a result, Martin Marietta Energy Systems, Inc. (Energy Systems), was asked to review options and to develop a comprehensive plan for inventory management and the ultimate disposition of DU accumulated at the gaseous diffusion plants (GDPs). An Energy Systems task team, under the chairmanship of T. R. Lemons, was formed in late 1989 to provide advice and guidance for this task. This report reviews options and recommends actions and objectives in the management of working inventories of partially depleted feed (PDF) materials and for the ultimate disposition of fully depleted uranium (FDU). Actions that should be considered are as follows. (1) Inspect UF{sub 6} cylinders on a semiannual basis. (2) Upgrade cylinder maintenance and storage yards. (3) Convert FDU to U{sub 3}O{sub 8} for long-term storage or disposal. This will include provisions for partial recovery of costs to offset those associated with DU inventory management and the ultimate disposal of FDU. Another recommendation is to drop the term tails'' in favor of depleted uranium'' or DU'' because the tails'' label implies that it is waste.'' 13 refs.

32 CFR 736.5 - Disposition of real and personal property under special statutory authority.

Science.gov (United States)

2010-07-01

... more than 50,000 must be deferred for 30 days after reporting the proposed transaction to the Armed... (10 U.S.C. 2662). (c) Disposition of strategic materials. Strategic materials may be disposed of by... disasters. Surplus property may also be disposed of to States for sale to small business concerns affected...

Excess plutonium disposition using ALWR technology

International Nuclear Information System (INIS)

Phillips, A.; Buckner, M.R.; Radder, J.A.; Angelos, J.G.; Inhaber, H.

1993-02-01

The Office of Nuclear Energy of the Department of Energy chartered the Plutonium Disposition Task Force in August 1992. The Task Force was created to assess the range of practicable means of disposition of excess weapons-grade plutonium. Within the Task Force, working groups were formed to consider: (1) storage, (2) disposal,and(3) fission options for this disposition,and a separate group to evaluate nonproliferation concerns of each of the alternatives. As a member of the Fission Working Group, the Savannah River Technology Center acted as a sponsor for light water reactor (LWR) technology. The information contained in this report details the submittal that was made to the Fission Working Group of the technical assessment of LWR technology for plutonium disposition. The following aspects were considered: (1) proliferation issues, (2) technical feasibility, (3) technical availability, (4) economics, (5) regulatory issues, and (6) political acceptance

Can-in-canister cold demonstration in DWPF (U)

International Nuclear Information System (INIS)

Kuehn, N.H.

1996-07-01

The Department of Energy Fissile Materials Disposition Program is evaluating a number of options for disposition of weapons-usable plutonium surplus to national defense needs. One of the immobilization options is the Can-In-Canister approach. In this option small cans of a plutonium glass, which contains a neutron absorber, are placed on a support structure in a large Savannah River Site Defense Waste Processing Facility (DWPF) canister. The top is then welded onto the canister. This canister is filled with High Level Waste (HLW) glass at the DWPF. The HLW glass provides the radiation source for proliferation resistance. These canisters are to be placed in a Federal Repository. To provide information on the technical feasibility of this option prior to the Record of Decision on plutonium disposition, the Department of Energy Fissile Materials Disposition Program funded a demonstration in the DWPF. This demonstration was conducted before the start of radioactive operations. Two test canisters containing cans of surrogate (non- radioactive) plutonium glass were successfully filled with simulated HLW glass at the DWPF using standard pouring procedures. One canister had twenty cans of surrogate plutonium glass. The other had eight cans of surrogate plutonium glass. After the canisters were filled, the contents of the canisters were examined to provide data on the effect of the rack and cans on the filling of the DWPF canister, the effect of the pour on the surrogate plutonium glass and the effect of the rack and cans on the simulated HLW glass. There was no deformation of the support racks during the pour. The simulated HLW glass filled all the regions around the rack and cans and the regions between the cans and the wall of the canister. This report discusses the design of the racks and cans, the modification of the DWPF canisters to accommodate the rack and cans, the conditions during the pours and the results of the post pour analysis

Disposition of excess material

International Nuclear Information System (INIS)

Hall, J.C.

1978-01-01

This paper reviews briefly the means available to an enrichment customer to dispose of excess material scheduled for delivery under a fixed-commitment contract, other than through termination of the related separative work. The methods are as follows: (1) sales; (2) use in facilities covered by other DOE contracts; and (3) assignment

Comparison of thorium-based fuels with different fissile components in existing BWRs

International Nuclear Information System (INIS)

Bjoerk, Klara Insulander; Fhager, Valentin; Demaziere, Christophe

2009-01-01

Three different types of thorium based BWR fuel have been developed, in each of which thorium was combined with a different fissile component, the three components being reactor grade plutonium, uranium enriched to 20% in uranium 235 and pure uranium 233. A BWR nuclear bundle design, based on the geometrical fuel assembly design GE14, was developed for each of these fissile components. The properties and performance of the corresponding fuel assemblies were investigated via full core calculations carried out for an existing BWR and compared with the ones of an ordinary Low Enriched Uranium (LEU) fuel, which was developed for reference. The fuel assemblies and cores were designed to meet existing fuel design criteria, and were then analyzed with regards to reactivity coefficients, delayed neutron fractions, control rod worths and shutdown margins. The results show that all three alternatives seem to be feasible, although some difficulties remain with complying with the thermal limits, and with the moderator temperature and coolant void coefficients of the U-233 containing fuel being positive under some circumstances. (author)

Signs, dispositions, and semiotic scaffolding.

Science.gov (United States)

Fernández, Eliseo

2015-12-01

In theoretical work we distinguish living beings from inanimate objects on the basis of some paramount attributes, such as agency and autonomy. These abstract features are not directly accessible to our scrutiny, but we surmise their nature through observation of the purpose-oriented behavior of organisms. I intend to show that organismal purposefulness springs from the intrinsic, constitutive kind of finality that is the hallmark of all semiotic transactions. To this aim I develop a dispositionalist account of organismal causation based on a distinction between two kinds of causal dispositions: fixed (efficient) dispositions and traveling dispositions. Fixed dispositions are rigidly attached to physical structures and processes; these are the dispositions regularly invoked in current discussions of causal explanation. Traveling dispositions are able to move freely from one location to another by becoming embodied into suitable supporting media. I introduce these notions to articulate a view of semiosis I deem best suited to the life sciences, and contend that sign tokens are vehicles of traveling dispositions. This account places the origin of purposive behavior at the interaction of physical and semiotic causation. To properly motivate the discussion I briefly review some recent developments in the philosophy of science concerning various forms of causation invoked by scientists across disciplines to frame explanations and make predictions. The ensuing discussion gives particular prominence to mechanistic (as distinct from mechanicist) explanatory accounts of biological phenomena. This review is followed by a brief characterization of a "nomological machine," a comprehensive schema introduced and developed by Nancy Cartwright with the goal of explaining causal mechanisms in a general setting. By capitalizing on this model's heuristic virtues I seek to formulate a compelling view of the interactions between physical and semiotic causation at play in semiotic

The personal dispositions of violent extremism

Directory of Open Access Journals (Sweden)

Davydov D.G.

2017-04-01

Full Text Available The paper presents the differences in the nature of extremism and radicalism, and the necessity of introducing the concept of "violent extremism." It is shown that the ideology is the explanation of extremist behavior, rather than its cause. The ideology of extremism often eclectic, contradictory and can easily be transformed by changing the object of hostility, depending on the situation. For the description of the psychological causes of extremism it is proposed to use the concept of personal disposition. Disposition is the preferred way to subjective interpretation of reality and reflects both the specific needs of a person as well the typical social situations where it realized and personal experience. Considered the following dispositions of violent extremism: the Cult of force and aggression, Intolerance, Out-group hostility Conventional coercion, Social pessimism and destructiveness, Mystical, Fighting and overcoming, Nihilism to law, Anti-subjectivism. It is proposed to use these dispositions as diagnostic criteria and for preventing and correcting.

12 CFR 34.83 - Disposition of real estate.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Disposition of real estate. 34.83 Section 34.83 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY REAL ESTATE LENDING AND APPRAISALS Other Real Estate Owned § 34.83 Disposition of real estate. (a) Disposition. A national bank may...

Overview of surplus weapons plutonium disposition

Energy Technology Data Exchange (ETDEWEB)

Rudy, G.

1996-05-01

The safe disposition of surplus weapons useable plutonium is a very important and urgent task. While the functions of long term storage and disposition directly relate to the Department`s weapons program and the environmental management program, the focus of this effort is particularly national security and nonproliferation.

NRC comprehensive records disposition schedule. Revision 3

International Nuclear Information System (INIS)

1998-02-01

Title 44 US Code, ''Public Printing and Documents,'' regulations issued by the General Service Administration (GSA) in 41 CFR Chapter 101, Subchapter B, ''Management and Use of Information and Records,'' and regulations issued by the National Archives and Records Administration (NARA) in 36 CFR Chapter 12, Subchapter B, ''Records Management,'' require each agency to prepare and issue a comprehensive records disposition schedule that contains the NARA approved records disposition schedules for records unique to the agency and contains the NARA's General Records Schedules for records common to several or all agencies. The approved records disposition schedules specify the appropriate duration of retention and the final disposition for records created or maintained by the NRC. NUREG-0910, Rev. 3, contains ''NRC's Comprehensive Records Disposition Schedule,'' and the original authorized approved citation numbers issued by NARA. Rev. 3 incorporates NARA approved changes and additions to the NRC schedules that have been implemented since the last revision dated March, 1992, reflects recent organizational changes implemented at the NRC, and includes the latest version of NARA's General Records Schedule (dated August 1995)

NRC comprehensive records disposition schedule. Revision 3

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-02-01

Title 44 US Code, ``Public Printing and Documents,`` regulations issued by the General Service Administration (GSA) in 41 CFR Chapter 101, Subchapter B, ``Management and Use of Information and Records,`` and regulations issued by the National Archives and Records Administration (NARA) in 36 CFR Chapter 12, Subchapter B, ``Records Management,`` require each agency to prepare and issue a comprehensive records disposition schedule that contains the NARA approved records disposition schedules for records unique to the agency and contains the NARA`s General Records Schedules for records common to several or all agencies. The approved records disposition schedules specify the appropriate duration of retention and the final disposition for records created or maintained by the NRC. NUREG-0910, Rev. 3, contains ``NRC`s Comprehensive Records Disposition Schedule,`` and the original authorized approved citation numbers issued by NARA. Rev. 3 incorporates NARA approved changes and additions to the NRC schedules that have been implemented since the last revision dated March, 1992, reflects recent organizational changes implemented at the NRC, and includes the latest version of NARA`s General Records Schedule (dated August 1995).

Chemical Disposition of Plutonium in Hanford Site Tank Wastes

Energy Technology Data Exchange (ETDEWEB)

Delegard, Calvin H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jones, Susan A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-05-07

This report examines the chemical disposition of plutonium (Pu) in Hanford Site tank wastes, by itself and in its observed and potential interactions with the neutron absorbers aluminum (Al), cadmium (Cd), chromium (Cr), iron (Fe), manganese (Mn), nickel (Ni), and sodium (Na). Consideration also is given to the interactions of plutonium with uranium (U). No consideration of the disposition of uranium itself as an element with fissile isotopes is considered except tangentially with respect to its interaction as an absorber for plutonium. The report begins with a brief review of Hanford Site plutonium processes, examining the various means used to recover plutonium from irradiated fuel and from scrap, and also examines the intermediate processing of plutonium to prepare useful chemical forms. The paper provides an overview of Hanford tank defined-waste–type compositions and some calculations of the ratios of plutonium to absorber elements in these waste types and in individual waste analyses. These assessments are based on Hanford tank waste inventory data derived from separately published, expert assessments of tank disposal records, process flowsheets, and chemical/radiochemical analyses. This work also investigates the distribution and expected speciation of plutonium in tank waste solution and solid phases. For the solid phases, both pure plutonium compounds and plutonium interactions with absorber elements are considered. These assessments of plutonium chemistry are based largely on analyses of idealized or simulated tank waste or strongly alkaline systems. The very limited information available on plutonium behavior, disposition, and speciation in genuine tank waste also is discussed. The assessments show that plutonium coprecipitates strongly with chromium, iron, manganese and uranium absorbers. Plutonium’s chemical interactions with aluminum, nickel, and sodium are minimal to non-existent. Credit for neutronic interaction of plutonium with these absorbers

Safeguards and security requirements for weapons plutonium disposition in light water reactors

International Nuclear Information System (INIS)

Thomas, L.L.; Strait, R.S.

1994-10-01

This paper explores the issues surrounding the safeguarding of the plutonium disposition process in support of the United States nuclear weapons dismantlement program. It focuses on the disposition of the plutonium by burning mixed oxide fuel in light water reactors (LWR) and addresses physical protection, material control and accountability, personnel security and international safeguards. The S and S system needs to meet the requirements of the DOE Orders, NRC Regulations and international safeguards agreements. Experience has shown that incorporating S and S measures into early facility designs and integrating them into operations provides S and S that is more effective, more economical, and less intrusive. The plutonium disposition safeguards requirements with which the US has the least experience are the implementation of international safeguards on plutonium metal; the large scale commercialization of the mixed oxide fuel fabrication; and the transportation to and loading in the LWRs of fresh mixed oxide fuel. It is in these areas where the effort needs to be concentrated if the US is to develop safeguards and security systems that are effective and efficient

Results of the Gallium-Clad Phase 3 and Phase 4 tasks (canceled prior to completion)

International Nuclear Information System (INIS)

Morris, R.N.

1998-08-01

This report summarizes the results of the Gallium-Clad interactions Phase 3 and 4 tasks. Both tasks were to involve examining the out-of-pile stability of residual gallium in short fuel rods with an imposed thermal gradient. The thermal environment was to be created by an electrical heater in the center of the fuel rod and coolant flow on the rod outer cladding. Both tasks were canceled due to difficulties with fuel pellet fabrication, delays in the preparation of the test apparatus, and changes in the Fissile Materials Disposition program budget

A statistically designed matrix to evaluate solubility, impurity tolerance, and thermal stability of plutonium-bearing glasses

International Nuclear Information System (INIS)

Peeler, D.K.; Meaker, T.F.; Edwards, T.B.; McIntyre, D.S.

1997-01-01

In support of the Department of Energy's (DOE) Office of Fissile Material Disposition (OFDM) Program, Westinghouse Savannah River Company (WSRC) is evaluating a unique lanthanide borosilicate glass to immobilize excess plutonium and other heavy metals. The lanthanide borosilicate (LaBS) glass system met all FY96 programmatic planning objectives. Those objectives were focused on (1) demonstrating 10 wt% Pu solubility, and (2) meeting preliminary product performance criteria. Although 10 wt% Pu solubility was demonstrated with product performance exceeding high level waste glasses based on PCT results, the LaBS system was not optimized

Linguistic variables, approximate reasoning and dispositions

Energy Technology Data Exchange (ETDEWEB)

Zadeh, L.A.

1983-07-01

Test-score semantics is applied to the representation of meaning of dispositions, that is, propositions with suppressed fuzzy quantifiers, e.g. overeating causes obesity, icy roads are slippery, young men like young women, etc. The concept of a disposition plays an especially important role in the representation of commonsense knowledge. 45 references.

Disposition of PUREX facility tanks D5 and E6 uranium and plutonium solutions

International Nuclear Information System (INIS)

Harty, D.P.

1993-12-01

Approximately 9 kilograms of plutonium and 5 metric tons of uranium in a 1 molar nitric acid solution are being stored in two PUREX facility vessels, tanks D5 and E6. The plutonium was accumulated during cleanup activities of the plutonium product area of the PUREX facility. Personnel at PUREX recently completed a formal presentation to the Surplus Materials Peer Panel (SMPP) regarding disposition of the material currently in these tanks. The peer panel is a group of complex-wide experts who have been chartered by EM-64 (Office of Site and Facility Transfer) to provide a third party independent review of disposition decisions. The information presented to the peer panel is provided in the first section of this report. The panel was generally receptive to the information provided at that time and the recommendations which were identified

The Dual Effects of Critical Thinking Disposition on Worry

Science.gov (United States)

Sugiura, Yoshinori

2013-01-01

This study investigated the relationship between disposition (people’s consistent motivation) toward critical thinking (CT) and worrying. In spite of its connection to psychopathology, worry is thought to represent an effort at problem-solving. Moreover, worry has been found to be underpinned by cognitive development, leading us to predict a positive relationship between worry and CT disposition. On the other hand, cognitive behavioral therapy, which involves techniques similar to CT, has been shown to be effective in reducing worrying, suggesting that increasing CT disposition decreases worrying. This study attempted to reconcile these seemingly contrasting predictions about the relationship between CT disposition and worrying by using multiple mediator analysis. A model was proposed wherein the mediators, responsibility to continue thinking and detached awareness of negative thinking, were related to two opposing predictions. The former is thought to lead to enhanced worrying and the latter to reduced worrying, with both positively related to CT disposition. A questionnaire study with university students (N = 760) revealed that CT disposition enhanced worrying by obliging people to continue thinking about a problem, but that it also reduced worrying by enhancing the detached and objective awareness of their negative thoughts. This study thus demonstrated the dual effects of CT disposition on worrying through different mediators. Thus, when enhancing CT disposition, it is important for educators to be aware of possible disadvantages apart from its worry-reducing effect. Future studies should therefore examine the underlying mechanisms of these two effects of CT disposition. PMID:24278160

Evaluation of Calcine Disposition Path Forward

International Nuclear Information System (INIS)

Birrer, S.A.; Heiser, M.B.

2003-01-01

This document describes an evaluation of the baseline and two alternative disposition paths for the final disposition of the calcine wastes stored at the Idaho Nuclear Technology and Engineering Center at the Idaho National Engineering and Environmental Laboratory. The pathways are evaluated against a prescribed set of criteria and a recommendation is made for the path forward

50 CFR 30.2 - Disposition of surplus range animals.

Science.gov (United States)

2010-10-01

... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Disposition of surplus range animals. 30.2... (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM RANGE AND FERAL ANIMAL MANAGEMENT Range Animals § 30.2 Disposition of surplus range animals. Disposition shall be made only during regularly scheduled disposal...

Preliminary concepts for materials measurement and accounting in critical facilities

International Nuclear Information System (INIS)

Cobb, D.D.; Sapir, J.L.

1978-01-01

Preliminary concepts are presented for improved materials measurement and accounting in large critical facilities. These concepts will be developed as part of a study that will emphasize international safeguarding of critical facilities. The major safeguards problem is the timely verification of in-reactor inventory during periods of reactor operation. This will require a combination of measurement, statistical sampling, and data analysis techniques. Promising techniques include integral measurements of reactivity and other reactor parameters that are sensitive to the total fissile inventory, and nondestructive assay measurements of the fissile material in reactor fuel drawers and vault storage canisters coupled with statistical sampling plans tailored for the specific application. The effectiveness of proposed measurement and accounting strategies will be evaluated during the study

DISPOSITION PATHS FOR ROCKY FLATS GLOVEBOXES: EVALUATING OPTIONS

International Nuclear Information System (INIS)

Lobdell, D.; Geimer, R.; Larsen, P.; Loveland, K.

2003-01-01

The Kaiser-Hill Company, LLC has the responsibility for closure activities at the Rocky Flats Environmental Technology Site (RFETS). One of the challenges faced for closure is the disposition of radiologically contaminated gloveboxes. Evaluation of the disposition options for gloveboxes included a detailed analysis of available treatment capabilities, disposal facilities, and lifecycle costs. The Kaiser-Hill Company, LLC followed several processes in determining how the gloveboxes would be managed for disposition. Currently, multiple disposition paths have been chosen to accommodate the needs of the varying styles and conditions of the gloveboxes, meet the needs of the decommissioning team, and to best manage lifecycle costs. Several challenges associated with developing a disposition path that addresses both the radiological and RCRA concerns as well as offering the most cost-effective solution were encountered. These challenges included meeting the radiological waste acceptance criteria of available disposal facilities, making a RCRA determination, evaluating treatment options and costs, addressing void requirements associated with disposal, and identifying packaging and transportation options. The varying disposal facility requirements affected disposition choices. Facility conditions that impacted decisions included radiological and chemical waste acceptance criteria, physical requirements, and measurement for payment options. The facility requirements also impacted onsite activities including management strategies, decontamination activities, and life-cycle cost

Neutron Assay System for Confinement Vessel Disposition

International Nuclear Information System (INIS)

Frame, Katherine C.; Bourne, Mark M.; Crooks, William J.; Evans, Louise; Mayo, Douglas R.; Miko, David K.; Salazar, William R.; Stange, Sy; Valdez, Jose I.; Vigil, Georgiana M.

2012-01-01

Los Alamos National Laboratory has a number of spherical confinement vessels (CVs) remaining from tests involving nuclear materials. These vessels have an inner diameter of 6 feet with 1-inch thick steel walls. The goal of the Confinement Vessel Disposition (CVD) project is to remove debris and reduce contamination inside the CVs. The Confinement Vessel Assay System (CVAS) was developed to measure the amount of special nuclear material (SNM) in CVs before and after cleanout. Prior to cleanout, the system will be used to perform a verification measurement of each vessel. After cleanout, the system will be used to perform safeguards-quality assays of (le)100-g 239 Pu equivalent in a vessel for safeguards termination. The CVAS has been tested and calibrated in preparation for verification and safeguards measurements.

The association between resting functional connectivity and dispositional optimism.

Science.gov (United States)

Ran, Qian; Yang, Junyi; Yang, Wenjing; Wei, Dongtao; Qiu, Jiang; Zhang, Dong

2017-01-01

Dispositional optimism is an individual characteristic that plays an important role in human experience. Optimists are people who tend to hold positive expectations for their future. Previous studies have focused on the neural basis of optimism, such as task response neural activity and brain structure volume. However, the functional connectivity between brain regions of the dispositional optimists are poorly understood. Previous study suggested that the ventromedial prefrontal cortex (vmPFC) are associated with individual differences in dispositional optimism, but it is unclear whether there are other brain regions that combine with the vmPFC to contribute to dispositional optimism. Thus, the present study used the resting-state functional connectivity (RSFC) approach and set the vmPFC as the seed region to examine if differences in functional brain connectivity between the vmPFC and other brain regions would be associated with individual differences in dispositional optimism. The results found that dispositional optimism was significantly positively correlated with the strength of the RSFC between vmPFC and middle temporal gyrus (mTG) and negativly correlated with RSFC between vmPFC and inferior frontal gyrus (IFG). These findings may be suggested that mTG and IFG which associated with emotion processes and emotion regulation also play an important role in the dispositional optimism.

The association between resting functional connectivity and dispositional optimism.

Directory of Open Access Journals (Sweden)

Qian Ran

Full Text Available Dispositional optimism is an individual characteristic that plays an important role in human experience. Optimists are people who tend to hold positive expectations for their future. Previous studies have focused on the neural basis of optimism, such as task response neural activity and brain structure volume. However, the functional connectivity between brain regions of the dispositional optimists are poorly understood. Previous study suggested that the ventromedial prefrontal cortex (vmPFC are associated with individual differences in dispositional optimism, but it is unclear whether there are other brain regions that combine with the vmPFC to contribute to dispositional optimism. Thus, the present study used the resting-state functional connectivity (RSFC approach and set the vmPFC as the seed region to examine if differences in functional brain connectivity between the vmPFC and other brain regions would be associated with individual differences in dispositional optimism. The results found that dispositional optimism was significantly positively correlated with the strength of the RSFC between vmPFC and middle temporal gyrus (mTG and negativly correlated with RSFC between vmPFC and inferior frontal gyrus (IFG. These findings may be suggested that mTG and IFG which associated with emotion processes and emotion regulation also play an important role in the dispositional optimism.

Dispositions, Emotions, Episodes and the Autonomous Learner.

Science.gov (United States)

Wesson, Anthony J.

1986-01-01

Explores the relationship between dispositions (i.e., continuities of inclinations and habits), episodic behavior, emotions, and desires; and the development of moral autonomy. Argues that autonomy requires a settled disposition toward the good. Contrasts theories of autonomy based on wants/desires and on ideals. (AYC)

Dispositional Optimism and Therapeutic Expectations in Early Phase Oncology Trials

Science.gov (United States)

Jansen, Lynn A.; Mahadevan, Daruka; Appelbaum, Paul S.; Klein, William MP; Weinstein, Neil D.; Mori, Motomi; Daffé, Racky; Sulmasy, Daniel P.

2016-01-01

Purpose Prior research has identified unrealistic optimism as a bias that might impair informed consent among patient-subjects in early phase oncology trials. Optimism, however, is not a unitary construct – it can also be defined as a general disposition, or what is called dispositional optimism. We assessed whether dispositional optimism would be related to high expectations for personal therapeutic benefit reported by patient-subjects in these trials but not to the therapeutic misconception. We also assessed how dispositional optimism related to unrealistic optimism. Methods Patient-subjects completed questionnaires designed to measure expectations for therapeutic benefit, dispositional optimism, unrealistic optimism, and the therapeutic misconception. Results Dispositional optimism was significantly associated with higher expectations for personal therapeutic benefit (Spearman r=0.333, poptimism was weakly associated with unrealistic optimism (Spearman r=0.215, p=0.005). In multivariate analysis, both dispositional optimism (p=0.02) and unrealistic optimism (poptimism (p=.0001), but not dispositional optimism, was independently associated with the therapeutic misconception. Conclusion High expectations for therapeutic benefit among patient-subjects in early phase oncology trials should not be assumed to result from misunderstanding of specific information about the trials. Our data reveal that these expectations are associated with either a dispositionally positive outlook on life or biased expectations about specific aspects of trial participation. Not all manifestations of optimism are the same, and different types of optimism likely have different consequences for informed consent in early phase oncology research. PMID:26882017

Study of plutonium disposition using the GE Advanced Boiling Water Reactor (ABWR)

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-04-30

The end of the cold war and the resulting dismantlement of nuclear weapons has resulted in the need for the U.S. to disposition 50 to 100 metric tons of excess of plutonium in parallel with a similar program in Russia. A number of studies, including the recently released National Academy of Sciences (NAS) study, have recommended conversion of plutonium into spent nuclear fuel with its high radiation barrier as the best means of providing long-term diversion resistance to this material. The NAS study {open_quotes}Management and Disposition of Excess Weapons Plutonium{close_quotes} identified light water reactor spent fuel as the most readily achievable and proven form for the disposition of excess weapons plutonium. The study also stressed the need for a U.S. disposition program which would enhance the prospects for a timely reciprocal program agreement with Russia. This summary provides the key findings of a GE study where plutonium is converted into Mixed Oxide (MOX) fuel and a 1350 MWe GE Advanced Boiling Water Reactor (ABWR) is utilized to convert the plutonium to spent fuel. The ABWR represents the integration of over 30 years of experience gained worldwide in the design, construction and operation of BWRs. It incorporates advanced features to enhance reliability and safety, minimize waste and reduce worker exposure. For example, the core is never uncovered nor is any operator action required for 72 hours after any design basis accident. Phase 1 of this study was documented in a GE report dated May 13, 1993. DOE`s Phase 1 evaluations cited the ABWR as a proven technical approach for the disposition of plutonium. This Phase 2 study addresses specific areas which the DOE authorized as appropriate for more in-depth evaluations. A separate report addresses the findings relative to the use of existing BWRs to achieve the same goal.

Measuring the Multicultural Dispositions of Preservice Teachers

Science.gov (United States)

Jensen, Bryant; Whiting, Erin Feinauer; Chapman, Sara

2018-01-01

Claims abound in the research literature regarding multicultural teacher dispositions, including how to foster them in teacher preparation programs. However, measures of multicultural dispositions of teachers that (a) capture the range of conceptually rich constructs and (b) demonstrate strong psychometric properties are not represented in the…

Nuclear materials management for safety and efficiency

Energy Technology Data Exchange (ETDEWEB)

NONE

1965-12-15

The use of nuclear materials in industrial processes presents management with some special problems which are peculiar to the atomic energy industry. If reactor fuel costs are to be kept low, too, each fuel element must yield the maximum economic 'bum-up' before it is withdrawn from service, and this calls for reliable non-destructive methods of measurement of 'burn-up' and appropriate records and fuel-changing schedules. The special hazards of radioactive materials call for special precautions and appropriate systems of handling and storage. A further danger unique to atomic energy is that of criticality - the possibility that an excessive concentration of fissile material may result in a chain reaction. Every part of the processing plant must be surveyed and checked to ensure that there is no build-up of fissile residues; in storage or transit there must be no aggregation of small lots. In the nuclear energy industry, too, the standards of purity required are much higher than in most other large-scale operation, so that stringent quality checks are needed

31 CFR 501.727 - Motion for summary disposition.

Science.gov (United States)

2010-07-01

... party's arguments. Any party opposing a motion for summary disposition must file a statement setting... be supported by evidence of the same type as that submitted with the motion for summary disposition...

Dispositions in Education: Nonentities Worth Talking about

Science.gov (United States)

Splitter, Laurance J.

2010-01-01

The concept of dispositions has commanded considerable attention in both philosophy and education. In this essay, Laurance Splitter draws on philosophy to take a fresh look at dispositions in education, specifically teacher education. Bypassing the pitfalls of both subjectivity and crude behaviorism, he proposes a conceptual framework in which…

Dispositional optimism and coping with pain.

Science.gov (United States)

Bargiel-Matusiewicz, K; Krzyszkowska, A

2009-12-07