The basis for fission product source term research in LOFT to support the NRC Severe Accident Research Program is presented. Probabilistic risk assessments are reviewed to identify risk-dominant accident sequences and an overview of source term research i...

This document presents a method of source term estimation that reflects the current understanding of source term behavior and that can be used during an event. The various methods of estimating radionuclide release to the environment (source terms) as a result of an ...

the Chernobyl nuclear accident of April, 1986 [refs. 9, 10]. The approximate radioactive source terms and inventories associated with this accident ...

The source term literature was reviewed to estimate aerosolized and respirable release fractions for accidents involving plutonium in high-explosive (HE) detonation and in fuel fires. For HE detonation, all estimates are based on the total amount of Pu. F...

The document describes a major advance in the technology for calculating source terms from postulated accidents at U.S. light-water reactors. The improved technology consists of (1) an extensive data base from severe accident research programs initiated f...

Fission product source terms for loss-of-coolant and core meltdown accidents in light water reactors are reviewed. The results presented in the Reactor Safety Study are summarized, and modifications of these results, due to more recent experimental studies, are described.

The source term can be mitigated by effective accident management. The goal of this work is the investigation of the influence of a number of accident management strategies on the source term of a VVER-1000-type reactor. This work is one of a series of studies investigating ...

This report addresses the potential LWR accident source term implication on accident evaluation assuming a change of the chemical form of iodine from elemental to cesium iodide. As a consequence, the escape of iodine to the environment and the risk to the...

...revise its current accident source term in design...radiological consequence analyses shall apply for...applicable design basis accidents 1 previously analyzed in the safety analysis report. 1 ...based upon a major accident, hypothesized for purposes of design analyses or...

Representative accident source terms patterned after the NUREG-1465 Source Term have been developed for high burnup fuel in BWRs and PWRs and for MOX fuel in a PWR with an ice-condenser containment. These source terms have been derived using ...

Hanford Site high-level radioactive waste tank accident analyses require chemical waste toxicity source terms to assess potential accident consequences. Recent reviews of the current methodology used to generate source terms and the need to periodically update the ...

Meaningful qualification testing of nuclear reactor components requires a knowledge of the radiation fields expected in a loss-of-coolant accident (LOCA). The overall objective of this program is to define the LOCA source terms and compare these with the ...

The system response in a transportation accident environment is an element to be considered in an overall Transportation System Risk Assessment (TSRA) framework. The system response analysis uses the accident conditions and the subsequent accident progression analysis to develop the accident ...

It is important to understand and model the chemical and physical behavior of vapor iodine species in containment environments for the following reasons: This behavior can contribute significantly to severe accident source terms; the development of accident mitigation or management strategies (e.g., an effective ...

The Accident Analysis Handbook (AAH) covers four generic facilities: fuel manufacturing, fuel reprocessing, waste storage/solidification, and spent fuel storage; and six accident types: fire, explosion, tornado, criticality, spill, and equipment failure. These are the accident types considered to make major contributions to the ...

This paper discusses salient aspects of methodology, assumptions, and modeling of various features related to estimation of source terms from two conservatively scoped severe accident scenarios in the Advanced Neutron Source (ANS) reactor at the Oak Ridge National Laboratory. Various containment configurations are ...

The purpose of the present paper is to describe a methodology which was developed as part of the QUASAR (Quantification and Uncertainty Analysis of Source Terms for Severe Accidents in Light Water Reactors) program at BNL. QUASAR is a large program which will apply the methodology described in this paper to severe ...

The purpose of this work is to use the results of the Savannah River Site K-Reactor Probabilistic Safety Assessment to determine the accident sequences and source terms for beyond design basis accidents. Additionally, the methodology necessary to allow the Reactor Accident Program to ...

The purpose of this work is to use the results of the Savannah River Site K-Reactor Probabilistic Safety Assessment to determine the accident sequences and source terms for beyond design basis accidents. Additionally, the methodology necessary to allow the Reactor Accident Program to ...

This volume comprises two appendixes: Chemical source terms for low-level mixed waste accidents, and radionuclide releases from facility accidents (HLW, LLW, LLMW(alpha and nonalpha)).

The behavior of the source term in a VVER-1000 type reactor is calculated using the Source Term Code Package (STCP). The input data are based on the Russian plant Zaporozhye-5. The selected accident sequence is a small break LOCA (Loss Of Coolant Accident...

The term 'ultimate risk' is used here to describe the probabilities and radiological consequences that should be incorporated in siting, containment design and accident management of nuclear power plants for hypothetical accidents. It is closely related with the source terms ...

There has been increased public interest in the potential effects of nuclear powerplant accidents since the Soviet reactor accident at Chernobyl. People have begun to look for more information about the amount of radioactivity that might be released into the environment as a result of such an accident. When this issue is discussed by ...

A severe accident study was conducted to evaluate conservatively scoped source terms and radiological consequences to support the Advanced Neutron Source (ANS) Conceptual Safety Analysis Report (CSAR). Three different types of severe accident scenarios we...

The definitions of source terms to reactor containments and source terms to the environment are discussed. A comparison is made between the TID-14844 example source term and the alternative source term described in NUREG-1465. ...

This document describes a major advance in the technology for calculating source terms from postulated accidents at US light-water reactors. The improved technology consists of (1) an extensive data base from severe accident research programs initiated following the TMI accident, (2) a set of ...

The high-dose early-effects research that has been continued has been done in the context of infrequent accidents with large radiation sources and the use of bone marrow transfusions for treating malignancies, especially leukemia. It thus seemed appropria...

Releases of gaseous radioactive materials were calculated for a series of postulated accidents for BWRs and PWRs. The purpose was the development of bases for selection of radiation measurement sensitivities for gaseous effluent monitoring instrumentation...

The study examines the influence of various accident parameters on (1) the probability of passenger compartment intrusion and (2) the relative ranking of intrusion sources (roof, door, etc.) in terms of frequency of occurrence. The injury hazard associate...

Consequences of nuclear fuel cycle facility accidents can be evaluated using aerosol release factors developed at Pacific Northwest Laboratory. These experimentally determined factors are compiled and consequence assessment methods are discussed. Release ...

A risk-based logic model is suggested as an appropriate basis for better predicting accident progression and ensuing source terms to the environment from process upset conditions in complex chemical process facilities. Under emergency conditions, decision...

Partial contents: Use of radiological accident experience in establishing appropriate perspectives in emergency planning; Health and environmental effects of the Chernobyl accident; Source terms derived from analyses of hypothetical accidents; Uranium yel...

This paper describes a personal computer-based program (GENSOR) that utilizes a simplified time-dependent approach for predicting the radionuclide releases during postulated reactor accidents. This interactive computer program allows the user to generate simplified source terms based on those severe accident ...

Radioactive afterheat is an important source term for the release of radionuclides in fusion systems under accident conditions. Heat transfer calculations are used to determine time-temperature histories in regions of interest, but the true source term needs to be the effective afterheat, which ...

Structural calculations were performed to evaluate the source-term nuclear fuels transport cask (ST Cask) under various hypothetical accident scenarios. (1) Three-dimensional transient dynamic analyses were performed to evaluate the strength of the cask's...

This report provides a brief summary of the current knowledge of severe accident source terms and suggests how this knowledge might be applied to a number of specific aspects of reactor safety. In preparing the report, consideration has been restricted to...

This paper reviews the key parameters comprising airborne radiological and chemical release source terms, discusses the ranges over which values of these parameters occur for plausible but severe waste management facility accidents, and relates the concom...

The objective of this work is to assess the source term and to evaluate the maximum hypothetical individual doses in European countries (including the Soviet Union) from the Chernobyl accident through the analyses of measurements of meteorological data, radiation fields, and airborne and deposited activity in these countries. Applying ...

Contents: The LWR fuel cycle; Generic models for demography, dispersion, dose; Source terms and likelihoods; Risk assessment.

This paper describes an approach to identifying source terms from possible accidents during the preclosure phase of a high-level nuclear waste repository. A review of the literature on repository safety analyses indicated that source term estimation is in a preliminary stage, largely based on ...

This paper discusses salient aspects of methodology, assumptions, and modeling of various features related to estimation of source terms from two conservatively scoped severe accident scenarios in the Advanced Neutron Source (ANS) reactor at the Oak Ridge...

The goal of this work is the search for an optimal accident management strategy to prevent containment failure and to stop the core/concrete interaction from hindering cavity bottom melt-through on the one hand and from ending the ex-vessel source term increase on the other hand, i.e., to terminate the accident. ...

This report contains the Appendices for the Analysis of Accident Sequences and Source Terms at Waste Treatment and Storage Facilities for Waste Generated by the U.S. Department of Energy Waste Management Operations. The main report documents the methodology, computational framework, and results of facility accident ...

Representative accident source terms patterned after the NUREG-1465 Source Term have been developed for high burnup fuel in BWRs and PWRs and for MOX fuel in a PWR with an ice-condenser containment. These source terms have been derived using ...

This study calculates source terms released into the environment at the Peach Bottom Atomic Power Station after containment failure during a postulated low-pressure, short-term station blackout severe accident. The severe accident analysis code MELCOR, version 1.8.1, was used in these ...

FAUST is an experimental program to give contributions to the assessment of the instantaneous source term in case of an LMFBR loss-of-flow accident with expanding fuel or sodium vapor. In the FAUST 1a-series, experiments with discharge of a gas-particle m...

The author states that new, technically defensible, methodologies to establish realistic source term values for nuclear reactor accidents will soon be available. Although these methodologies will undoubtedly find widespread use in the development of accident response procedures, the author states that it is less ...

The purpose of this work is to describe some of the research being performed at ORNL in support of the effort to describe, as realistically as possible, fission product source terms for nuclear reactor accidents. In order to make this presentation manageable, only those studies directly concerned with fission product behavior, as ...

A detailed review of the available light water reactor source term information is presented as a technical basis for development of updated source terms into the containment under severe accident conditions. Simplified estimates of radionuclide release and transport characteristics are ...

This report contains the Appendices for the Analysis of Accident Sequences and Source Terms at Waste Treatment and Storage Facilities for Waste Generated by the U.S. Department of Energy Waste Management Operations. The main report documents the methodolo...

The goal of this work is the investigation of the influence of different accident management strategies on the thermal-hydraulics in the containment during a Large Break Loss of Coolant Accident with a large containment leak from the beginning of the accident. The increasing relevance of terrorism suggests a closer look at this kind of ...

A new perspective on the consequences of a potential reactor accident are discussed. TMI accident showed that the release of hazardous radionuclide iodine-131 was radically different than specified in the NRC regulatory model. The reactor safety study (WASH-1400) also had many conservative assumptions (called ...

The principal objectives of the fission product release program currently in progress at Oak Ridge National Laboratory are to determine the quantity of radiologically significant fission products released from defected light water reactor (LWR) fuel rods under accident conditions, identify their chemical and physical forms, and interpret the results for use as input to ...

The principal objectives of the fission product release program currently in progress at Oak Ridge National Laboratory are to determine the quantity of radiologically significant fission products released from defected light water reactor (LWR) fuel rods under accident conditions, identify their chemical and physical forms, and interpret the results for use as input to ...

This paper describes a multilaboratory research program that is directed toward addressing many questions that analysts face when performing air cleaning accident consequence assessments. The program involves developing analytical tools and supportive experimental data that will be useful in making more realistic assessments of accident ...

This paper discusses salient aspects of the methodology, assumptions, and modeling of various features related to estimation of source terms from an accident involving a molten core-concrete interaction event (with and without flooding) in the Advanced Neutron Source (ANS) reactor at the Oak Ridge National ...

A severe accident study was conducted to evaluate conservatively scoped source terms and radiological consequences to support the Advanced Neutron Source (ANS) Conceptual Safety Analysis Report (CSAR). Three different types of severe accident scenarios were postulated with a view of evaluating ...

The MELCOR severe accident code version 1.8.4QK has been employed to calculate the timing of events and source terms released into the environment for several hypothetical severe accidents as Unit 1 of the Juragua VVER 440-213 plant, located near Cienfuegos, Cuba. Different severe accidents ...

A review. (H.H.D.)17:027632Topics discussed include: procedures to be followed the first 12 hr after an accident; later emergency period; clinical features of the acute radiation syndrome; therapy and long-term follow-up studies; hospital disaster plans for radiation accidents; problems of psychological upset; ...

This paper presents the site suitability source terms for the Modular High Temperature Gas-Cooled Reactor (MHTGR). The MHTGR program has identified a spectrum of accident release scenarios that form a basis for determining the MHTGR site suitability source terms. This basis, consistent with ...

Assessment of the environmental consequences of an accident in a fuel cycle facility ultimately involves calculating the atmospheric dispersion of radioactive materials and estimating the radiation dose to the surrounding population. Some uncertainty lies in the estimate of the nuclear facility source term to be used for atmospheric ...

Software & Copyright Submittal The tool used to analyze the progression of accidents in the DWPF is called an Accident Progression Event Tree (APET). The APET methodology groups analyzed progressions into a series of bins, based on similarities in their characteristics. DWPFASTXL is an Excel spreadsheet that can be used to calculate radiological ...

This paper describes the difficulties of evaluation of source term because the difficulties in evaluating the transport terms (wind speed and direction) during a long period of time. In spite of these difficulties, the MICAR Code of the Institut de Protec...

Source Term (ST) is generally known as the amount of the radio-nuclides(fission products along with activation and Actinides) that can be released from a nuclear power plant in an accident. The ST can be more accurately defined as the quantity, timing, composition, chemical and physical form of radio-nuclides. The amount of ...

In support of the Nuclear Regulatory Commission's (NRC's) assessment of the risk from severe accidents at commercial nuclear power plants in the U.S. reported in NUREG-1150, the Severe Accident Risk Reduction Program (SAARP) has completed a revised calcul...

This report documents the methodology, computational framework, and results of facility accident analyses performed for the U.S. Department of Energy (DOE) Waste Management Programmatic Environmental Impact Statement (WM PEIS). The accident sequences pote...

This report examines the various sources of radiological land contamination; its extent; its impacts on man, agriculture, and the environment; countermeasures for mitigating exposures; radiological standards; alternatives for achieving land decontamination and cleanup; and possible alternatives for utilizing the land. The major potential sources of ...

The status of the accident analysis for the Ulysses outer planetary space science mission is presented. This mission employs a Radioisotope Thermoelectric Generator (RTG) as the prime electrical power source for the spacecraft. The RTG employs silicon-germanium thermoelectric couples to produce electricity from the heat energy that results from the decay ...

This paper discusses salient aspects of the methodology, assumptions, and modeling of various features related to estimation of source terms from an accident involving a molten core-concrete interaction event (with and without flooding) in the Advanced Ne...

The Light-Weight Radioisotope Heater Unit (LWRHU) Final Safety Analysis Report (FSAR), Volume 2, Accident Model Document (AMD) describes potential accident scenarios during the Galileo mission and evaluates the response of the LWRHUs to the associated accident environments. Any resulting source ...

The Light-Weight Radioisotope Heater Unit (LWRHU) Final Safety Analysis Report (FSAR), Volume 2, Accident Model Document (AMD) describes potential accident scenarios during the Galileo mission and evaluates the response of the LWRHUs to the associated accident environments. Any resulting source ...

The methodological framework and program plan for systematic quantification and propagation of uncertainties in radiological source terms for light water reactors are presented. The QUASAR methodology is based on detailed sensitivity analysis of the Source Term Code Package (STCP), followed by a systematic ...

This report is about accidents with the potential to release radioactive materials into the environment surrounding the Spallation Neutron Source (SNS). As shown in Chap. 2, the inventories of radioactivity at the SNS are dominated by the target facility. Source terms for a wide range of target facility ...

The definition and the multidimensionality aspects of accident management have been reviewed. The suggested elements in the development of a programme for severe accident management have been identified and discussed. The strategies concentrate on the two tiered approaches. Operative management utilizes the plant's equipment and operators ...

The emphasis is on effects of the accident on the region of southcentral Pennsylvania that surrounds the station site. A variety of data sources were utilized including published documents and statistics, household surveys, other research about the accident, newspaper files, and interviews with key informants. Findings are grouped into ...

Several safety evaluations for large High Temperature Gas Cooled Reactors (HTGR), using a Prestressed Concrete Reactor Vessel (PCRV) design, have concluded that Unrestricted Core Heatup Accidents (UCHA) present the most important severe accidents, resulting in the dominant source term. While the core ...

As part of a Nuclear Regulatory Commission (NRC) research program to evaluate the impact of using mixed-oxide (MOX) fuel in commercial nuclear power plants, a study was undertaken to evaluate the impact of the usage of MOX fuel on the consequences of postulated severe accidents. A series of 23 severe accident calculations was performed using MELCOR 1.8.5 ...

Much of the information made available by the U.S.S.R. on the release of radionuclides during the reactor accident at the Chernobyl Atomic Energy Station is described. The release of radionuclides took place in two stages. The first, which was brief but intense, can be understood in terms of the known behavior of reactor fuel during reactivity insertion ...

This report presents supplemental information for the document Analysis of Accident Sequences and Source Terms at Waste Treatment, Storage, and Disposal Facilities for Waste Generated by US Department of Energy Waste Management Operations. Additional technical support information is supplied concerning treatment of transuranic waste by ...

Preliminary accident analyses and radiological source term evaluations have been conducted for transuranic waste (TRUW) as part of the US Department of Energy (DOE) effort to manage storage, treatment, and disposal of radioactive wastes at its various sites. The approach to assessing radiological releases from facility ...

Activities involving regulatory implementation of updated source term information were pursued. These activities include the identification of the source term, the identification of the chemical form of iodine in the source term, and the timing of the ...

The intent of this safety test plan is to outline particular kinds of safety tests designed to produce information which would be useful in the safety analysis process. The program deals primarily with the response of the RTG to accident environments; accordingly two criteria were established: (1) safety tests should be performed for environments which are the most critical in ...

The main objective of the project was to use the Source Term Code Package (STCP) to obtain a specific source term for those accident sequences deemed dominant as a result of probabilistic safety analyses (PSA) for the Laguna Verde Nuclear Power Plant (CNL...

A consistency review of accident analyses in US Department of Energy (DOE) safety, environmental, and emergency planning documents is presented. The range of and key differences in driving assumptions used in accident definition and frequency assessment, radiological source term generation, and atmospheric ...

In 1962 tile US Atomic Energy Commission published TID-14844, ``Calculation of Distance Factors for Power and Test Reactors`` which specified a release of fission products from the core to the reactor containment for a postulated accident involving ``substantial meltdown of the core``. This ``source term``, tile basis for tile NRC`s ...

This paper presents the site suitability source terms for the Modular High Temperature Gas-Cooled Reactor (MHTGR). The MHTGR program has identified a spectrum of accident release scenarios that form a basis for determining the MHTGR site suitability sourc...

Only results that had been discussed publicly, had been published in the open literature, or were available in preliminary reports as of September 30, 1984, are included here. More than 20 organizations are participating in source-term programs, which have been undertaken to examine severe accident phenomena in light-water power reactors (including the ...

A scoping study of spent fuel cask transportation accidents was performed to provide the NRC with an assessment of existing information and to recommend, on a priority basis, the additional information that should be obtained to allow specification of increasingly realistic source terms. The scope was limited to the escape of ...

The disposal of sealed sources from industrial irradiators usually includes reuse or recycling where feasible, and then long-term storage at a waste management facility until the sources have decayed to a level at which they can be disposed of as essentially non-radioactive waste. The space required for this storage, and the time ...

The vaporization of tungsten from the APT spallation target dominates the radiological source term for unmitigated target overheating accidents. Chemical reactions of tungsten with steam which persist to tungsten temperatures as low as 800 C result in the...

Radionuclides released during core-concrete interactions (CCI) can make a major contribution to the severe accident source term. Despite recent advances in understanding, significant uncertainties remain in the prediction of these releases. In the present...

Currently, chemical dispersion calculations performed for safety analysis of DOE facilities assume a Pasquill D-Stability Class with a 4.5 m/s windspeed. These meteorological conditions are assumed to conservatively address the source term generation mech...

Periodically it is necessary to re-examine the implications of new source terms for neighboring offsite populations as Probabilistic Risk Assessment (PRA) and Severe Accident studies mature, and lead to a better understanding of the progression of hypothe...

Fission product release from overheated fuel is one of the key phenomena controlling the source terms in hypothetical severe accidents. An experimental and analytical program, Verification Experiment of Gas/Aerosol release (VEGA), was initiated at JAERI t...

Brookhaven National Laboratory has performed a series of probabilistic consequence assessment calculations for nuclear reactor siting. This study takes into account recent insights into severe accident source terms and examines consequences in a risk based format consistent with the quantitative health objectives (QHOs) of the NRC`s ...

This document provides Unit Liter Dose factors, atmospheric dispersion coefficients, breathing rates and instructions for using and customizing these factors for use in calculating radiological doses for accident analyses in the Hanford Tank Farms.

This book contains the proceedings on nuclear safety after Three Mile island and Chernobyl. Topics covered include: Design for safety; Man-machine interaction; Source terms and consequence; and accident response.

The contribution deals with the transport of fission products in overheated reactor fuel. An introductory chapter outlines the relevance of this transport for the determination of the source term at severe accidents with a nuclear reactor, with general re...

Volume II presents the information and approach used to estimate the relative probabilities and source terms for various potential accidents postulated to result in fuel release. It then takes up the subject of the radiological analyses.

Automated Emergency Response (ER) systems are playing a greater role in providing prompt and reliable predictions of the impact of inadvertent releases of hazardous materials to the environment. Observed and forecast environmental and accident source term...

It is a concern in the current safety analysis of nuclear reactors to understand the different release mechanisms of fission products to accurately determine the radiological source term for a wide variety of accidents. The mechanism which is least unders...

Appendix A-5 of Draft Regulatory Guide DG-1199 'Alternative Radiological Source Term for Evaluating Design Basis Accidents at Nuclear Power Reactors' provides guidance - applicable to RADTRAD MSIV leakage models - for scaling containment aerosol concentra...

The release of UO2 aerosols from pools of sodium was studied in a series of ten experiments. These were designed to provide a mechanistic basis for evaluating the radiological source term associated with a postulated, hypothetical core disruptive accident...

...receive a radiation dose in excess of 0...total effective dose equivalent (TEDE). (iii) Adequate radiation protection is provided...personnel receiving radiation exposures in excess of 0...total effective dose equivalent...

The objectives of this work were to evaluate the consequences of a postulated accident to onsite security personnel stationed near the facility during operations of the Godiva IV critical assembly and to identify controls needed to protect these personnel in case of an extreme criticality excursion equivalent to the design-basis accident (DBA). This paper ...

A recent development in criticality accident analysis is the deterministic calculations of the transport of fission products and actinides through the barriers of the physical facility. The knowledge of the redistribution of the materials inside the facility will help determine the reentry and clean-up procedures. The amount of radioactive materials released to the environment ...

Pressurized ejection of melt from a reactor pressure vessel has been identified as an important element of a severe reactor accident. Copious aerosol production is observed when thermitically generated melts pressurized with nitrogen or carbon dioxide to 1.3 to 17 MPa are ejected into an air atmosphere. Aerosol particle size distributions measured in the tests have modes of ...

A probabilistic approach to quantifying uncertainties in the progression of severe reactor accidents is formulated and applied to the Source Term Code Package. It is shown that quantification of uncertainties at the basic level of input parameters reveals broad time-dependent uncertainties in the core melt progression, containment ...

The primary objective of this report is to provide the technical basis for development of recommendations for updates to the NUREG-1465 Source Term for BWRs that will extend its applicability to accidents involving high burnup (HBU) cores. However, a secondary objective is to re-examine the fundamental characteristics of the ...

The Surry low power and shutdown probabilistic risk analysis (PRA) is an ongoing project at Brookhaven National Laboratory (BNL) to identify and quantify potential accident scenarios that may occur in a pressurized water reactor (PWR) during low power and shutdown. It was initiated as a result of various incidents and accidents that have occurred within ...

Human health risks as a consequence of potential radiological releases resulting from plausible accident scenarios constitute an important consideration in the US Department of Energy (DOE) national program to manage the treatment, storage, and disposal of wastes. As part of this program, the Office of Environmental Management (EM) is currently preparing a Programmatic ...

This report presents a set of precalculated doses based on a set of postulated accident releases and intended for use in emergency planning and emergency response. Doses were calculated for the PWR (Pressurized Water Reactor) accident categories of the Reactor Safety Study (WASH-1400) using the CRAC (Calculations of Reactor Accident ...

A review of accident analyses in recent US Department of Energy (DOE) Environmental Impact Statements (EISs) was conducted to evaluate the consistency among approaches and to compare these approaches with existing DOE guidance. The review considered several components of an accident analysis: the overall scope, which in turn should reflect the scope of the ...

Different hypothetical accident sequences have been simulated at Unit 1 of the Juragua nuclear power plant in Cuba, a plant with two VVER-440 V213 units under construction. The computer code MELCOR was employed for these simulations. The sequences simulated are: (1) a design-basis accident (DBA) large loss of coolant accident (LOCA) ...

In support of the U.S. Department of Energy`s (DOE`s) Waste Management Programmatic Environmental Impact Statement, Argonne National Laboratory has developed WASTE-ACC, a computational framework and integrated PC-based database system, to assess atmospheric releases from facility accidents. WASTE-ACC facilitates the many calculations for the accident ...

This document has been prepared as a user's guide for the computer program RISKIN developed at Sandia National Laboratories. The RISKIN code generates integrated risk tables and the weighted mean risk associated with a user-selected set of consequences from up to five output files generated by the MELCOR Accident Consequence Code System (MACCS). Each MACCS output file ...

ORNL's Advanced Neutron Source (ANS) will be a new user facility for all kinds of neutron research, centered around a research reactor of unprecedented neutron beam flux. A defense-in-depth philosophy has been adopted. In response to this commitment, ANS Project management has initiated severe accident analysis and related technology development ...

ORNL`s Advanced Neutron Source (ANS) will be a new user facility for all kinds of neutron research, centered around a research reactor of unprecedented neutron beam flux. A defense-in-depth philosophy has been adopted. In response to this commitment, ANS Project management has initiated severe accident analysis and related technology development efforts ...

Differences and similarities in severe accident progression and phenomena between commercial Light Water Reactors (LWR) and metal-fueled isotopic production Heavy Water Reactors (HWR) are described. It is very important to distinguish between accident progression in the two systems because each reactor type behaves in a unique manner to a fuel melting ...

French safety philosophy as concerns severe PWR accidents has already been outlined by the Director of CEA/IPSN in an article published in ''Nuclear Safety''. Therefore the present paper will focus on: (a) the French reference source terms, as used for el...

In this study, risk-significant pressurized-water reactor severe accident sequences are examined using MELCOR 1.8.5 to explore the range of fission product releases to the reactor containment building. Advances in the understanding of fission product rele...

The report presents results of analyses of the environmental releases of fission products (source terms) for severe accident scenarios in a pressurized water reactor with an ice-condenser containment. The analyses were performed to support the Severe Acci...

analysis of Russian marine reactors and naval fuel when considering possible accidents and consequences The present report deals with source terms for accidents involving Russian marine nuclear reactors icebreaker and submarine nuclear reactors. As discussed in the other NKS-report from this project (Nuc

In the source term evaluation for severe core damage accident of light water reactor, the uncertainty on the evaluation by the occurrence of volatile iodic compounds is reduced by large margine by using the method of fixation of FP iodine as silver iodide...

The Annular Core Research Reactor (ACRR) Source Term (ST) Experiment program was designed to obtain time-resolved data on the release of fission products from irradiated fuels under well-controlled light water reactor severe accident conditions. The ST-1 ...

The Fast Flux Test Facility (FFTF) has been proposed as a production facility for tritium and medical isotopes. A range of postulated accidents related to ex-reactor irradiated fuel and target handling were identified and evaluated using new source terms ...

The bibliography contains citations concerning the impact of radiation accidents on humans. Citations discuss exposure assessment, malfunction and misuse of radiation sources, dosimetry, radiation epidemiology, radiation-induced neoplasms, and nuclear facility licensing. Environmental and occupational exposures, case studies, nuclear fallout, and radiation ...

Based on recent experiments and accident analysis at Sandia National Laboratories (SNL), four conclusions relevant to severe accident source-term evaluation can be drawn. First, the melt composition at the time of reactor pressure vessel failure is an imp...

This report presents results of analyses of the enviromental releases of fission products (source terms) for severe accident scenarios in a pressurized water reactor with a subatmospheric containment design. The analyses were performed to support the Severe Accident Risk Reduction/Risk Rebaselining Program (SARRP) ...

This report presents results of analyses of the environmental releases of fission products (source terms) for severe accident scenarios in a pressurized water reactor with an ice-condenser containment. The analyses were performed to support the Severe Accident Risk Reduction/Risk Rebaselining Program (SARRP) which ...

Accident analysis for U.S. Department of Energy (DOE) nuclear facilities is an integral part of the overall safety basis developed by the contractor to demonstrate facility operation can be conducted safely. An appropriate documented safety analysis for a facility discusses accident phenomenology, quantifies source ...

An uncertainty and sensitivity analysis of early health consequences of severe accidents at nuclear power plants as a function of the emergency response parameters has been performed using a probabilistic consequence assessment code. The importance of various emergency response parameters in predicting the consequences for a range of accident ...

The Lawrence Livermore National Laboratory Atmospheric Release Advisory Capability (ARAC) responded to the Chernobyl nuclear reactor accident in the Soviet Union by utilizing long-range atmospheric dispersion modeling to estimate the amount of radioactivity released (source term) and the radiation dose distribution due to exposure to ...

An alternative method to reconstruct the source term of a nuclear accident is proposed. The technique discussed here involves the use of in-situ gamma spectrometry. The validation of the applied methodology has been possible through the monitoring of rout...

This paper reviews the key parameters comprising airborne radiological and chemical release source terms, discusses the ranges over which values of these parameters occur for plausible but severe waste management facility accidents, and relates the concomitant sensitivities of emergency planning zone boundaries predicted on calculated ...

The nuclear source term, defined as the quantity, timing, and characteristic of the release of radioactive material to the environment following a core-melt accident, was thoroughly debated in 1985. This debate, summarized here, turns on the Nuclear Regulatory Commission's (NRC) source ...

In the frame of the KfK research program FAUST, contributions are given to the assessment of the instantaneous source term in case of an LMFBR loss-of-flow accident with expanding fuel or sodium vapour. The main goal of the program is to achieve informati...

Accident source terms, source term probabilities, consequences, and risks are developed for ship collisions that might occur in US ports during the shipment of spent fuel from foreign research reactors to the United States.

Accident source terms, source term probabilities, consequences, and risks are developed for ship collisions that might occur in U.S. ports during the shipment of spent fuel from foreign research reactors to the United States in break-bulk freighters.

Information is presented concerning chemical forms of fission product iodine in the primary circuit; chemical forms of fission product iodine in the containment building; summary of iodine chemistry in light water reactor accidents; and impact of the radiodine source term on the potassium iodide issue.

The PARTITION computer code has been used in the SRS K-reactor Full Scope PSA to cluster the many source terms resulting from the accident progression analysis into a manageable number of averaged source terms. Very little guidance is given in Reference 1 for use of the various options that are ...

NUREG-0956 describes the NRC staff and contractor efforts to reassess and update the agency's analytical procedures for estimating accident source terms for nuclear power plants. The effort included development of a new source term analytical procedure - a set of computer codes - that ...

The primary objective of the Accident Initiation and Progression Analysis (AIPA) Program is to provide guidance for high-temperature gas-cooled reactor (HTGR) safety research and development. Among the parameters considered in estimating the uncertainties in site boundary doses are uncertainties in fission product source terms ...

The fundamental liability of any nuclear reactor is the possibility of exposing the public and environment to an excessive level of nuclear radiation. In a previous paper, the authors addressed the risk and potential vulnerability assessment of a maximum hypothetical release accident (MHRA) for the AGN-201M reactor at the University of New Mexico. The MHRA is defined as the ...

The purpose of this report is to provide technical support for the physically-based source term which is proposed as the licensing design basis fission product release from a major core accident for the Passive Advanced Light Water Reactor (ALWR) in Volume 3, Section 5 of the ALWR Requirements Document. A substantial body of new ...

MELCOR is a fully integrated, engineering-level computer code that models the progression of severe accidents in light water reactor nuclear power plants. MELCOR is being developed at Sandia National Laboratories for the US Nuclear Regulatory Commission as a second-generation plant risk assessment tool and the successor to the Source ...

The US Department of Energy requires Westinghouse Savannah River Company to safely operate the chemical separations facilities at the Savannah River Site (SRS). As part of the safety analysis program, simulation of a proposed frame waste recovery (FWR) system is needed to determine the possible accident consequences that may affect public safety. This paper details the ...

Sodium-cooled fast reactors (SFRs) continue to be proposed and designed throughout the United States and the world. Although the number of SFRs actually operating has declined substantially since the 1980s, a significant interest in advancing these types of reactor systems remains. Of the many issues associated with the development and deployment of SFRs, one of high regulatory importance is the ...

The THALES-2 code is an integrated severe accident analysis code developed at the Japan Atomic Energy Research Institute in order to simulate the accident progression and transport of radioactive material for probabilistic safety assessment (PSA) of a nuclear power plant. As part of a level 3 PSA being performed at JAERI for a 1,100 MWe BWR-5 with a ...

The risks associated with the transport of spent nuclear fuel by truck and rail have been reexamined and compared to results published in NUREG-O170 and the Modal Study. The full reexamination considered transport of PWR and BWR spent fuel by truck and rail in four generic Type B spent fuel casks. Because they are typical, this paper presents results only for transport of PWR spent fuel in ...

This work deals with the radiological accidents in medicine. In medicine, the radiation accidents on medical personnel and patients can be the result of over dosage and bad focusing of radiotherapy sealed sources. Sometimes, the accidents, if they are unk...

Most laboratory safety programs include inspections to identify hazards and thereby control accidents. There are certain elements that must be a part of a successful inspection and control process. These are a systematic and consistent inspection procedure, a reliable evaluation of identified hazards, and effective follow-up actions. Laboratory management, through its ...

Current US Department of Energy (DOE) guidance on the performance of accident analyses supported an environmental impact statement (EIS) stresses a graded approach that emphasizes the most important risks, calls for the evaluation of frequencies as well as consequences for severe accident scenarios, and discourages the use of bounding analyses that ...

The in-depth reviews of risk assessments performed specifically for the Limerick and Shoreham plants have identified accident sequences that are important contributors to core damage frequency (CDF). These plants are boiling water reactors (BWRs) with Mark-II containment designs. Plant features and operator actions that have been found to be important for either preventing or ...

The MELCOR code, developed by Sandia National Laboratories, is capable of simulating the severe accident phenomena of light water reactor nuclear power plants (NPPs). A specific large-break loss-of-coolant accident (LOCA) for Kuosheng NPP is simulated with the use of the MELCOR 1.8.4 code. This accident is induced by a double-ended ...

The source term literature was reviewed to estimate aerosolized and respirable release fractions for accidents involving plutonium in high-explosive (HE) detonation and in fuel fires. For HE detonation, all estimates are based on the total amount of Pu. For fuel fires, all estimates are based on the amount of Pu oxidized. I based my ...

This report documents the methodology, computational framework, and results of facility accident analyses performed for the U.S. Department of Energy (DOE) Waste Management Programmatic Environmental Impact Statement (WM PEIS). The accident sequences potentially important to human health risk are specified, their frequencies are assessed, and the resultant ...

Meaningful qualification testing of nuclear reactor components requires a knowledge of the radiation fields expected in a loss-of-coolant accident (LOCA). The overall objective of this program is to define the LOCA source terms and compare these with the output of various simulators employed for radiation qualification testing. The ...

In this paper, attention is limited to a single accident progression sequence, namly a station blackout accident in a BWR with a Mark I containment building. Identified as an important accident in the draft version of NUREG-1150 a station blackout involves loss of both off-site power and dc power resulting in failure of the diesels to ...

This book reviews the nuclear accident at Three Mile Island, Pennsylvania including its causes, the cleanup process, and its impacts on society and the nuclear power industry. Individual chapters address nuclear energy fundamentals; the accident; the cleanup; media coverage and public perceptions; effects on the local community; economic, legal, and ...

This section of the Accident Model Document (AMD) presents the appendices which describe the various analyses that have been conducted for use in the Galileo Final Safety Analysis Report 2, Volume 2. Included in these appendices are the approaches, techniques, conditions and assumptions used in the development of the analytical models plus the detailed results of the analyses. ...

The Radiological Assessment System for Consequence AnaLysis (RASCAL) is a new MS-DOS-based dose assessment model which has been written for the US Nuclear Regulatory Commission for use during response to radiological emergencies. RASCAL is designed to provide crude estimates of the effects of an accident while the accident is in progress and only limited ...

Safety features and attributes of molten salt reactors (MSR) are described. The unique features of fluid fuel reactors of on-line continuous processing and the ability for so-called external cooling result in simple and safe designs with low excess reactivity, low fission product inventory, and small source term. These, in turn, make a criticality ...

This paper presents the results and insights gained from MELCOR analyses of two severe accident scenarios, a Loss of Coolant Accident (LOCA) and a Station Blackout (TMLB) in Oconee, a Babcock & Wilcox (B&W) designed PWR with a large dry containment, and comparisons with Source Term Code Package (STCP) ...

This paper presents the results and insights gained from MELCOR analyses of two severe accident scenarios, a Loss of Coolant Accident (LOCA) and a Station Blackout (TMLB) in Oconee, a Babcock Wilcox (B W) designed PWR with a large dry containment, and comparisons with Source Term Code Package (STCP) calculations ...

This section of the Accident Model Document (AMD) presents the appendices which describe the various analyses that have been conducted for use in the Galileo Final Safety Analysis Report II, Volume II. Included in these appendices are the approaches, techniques, conditions and assumptions used in the development of the analytical models plus the detailed results of the ...

A principal consideration in developing waste management strategies is the relative importance of Potential radiological and hazardous releases to the environment during postulated facility accidents with respect to protection of human health and the environment. The Office of Environmental Management (EM) within the US Department of Energy (DOE) is currently formulating an ...

The Fast Flux Test Facility (FFTF) has been proposed as a production facility for tritium and medical isotopes. A range of postulated accidents related to ex-reactor irradiated fuel and target handling were identified and evaluated using new source terms for the higher fuel enrichment and for the tritium and medical isotope targets. In ...

Standardized source terms, based on a specified release of fission products during potential accidents at commercial light water nuclear reactors, have been used for a long time for regulatory purposes. The siting of nuclear power plants, for example, which is governed by Part 100 of the Code of Federal Regulations Title 10, has ...

A bibliography on sources of information about American manned spacecraft accidents compiled by the NASA Headquarters Library.

MELCOR is a fully integrated computer code that models all phases of the progression of severe accidents in light water reactor nuclear power plants, and is being developed for the US Nuclear Regulatory Commission (NRC) by Sandia National Laboratories (SNL). Brookhaven National Laboratory (BNL) has a program with the NRC called ``MELCOR Verification, Benchmarking, and ...

MELCOR is a fully integrated computer code that models all phases of the progression of severe accidents in light water reactor (LWR) nuclear power plants and is being developed for the US Nuclear Regulatory Commission (NRC) by Sandia National Laboratories. Brookhaven National Laboratory (BNL) has a program with the NRC called MELCOR Verification, Benchmarking, and ...

In Korea, Wolsong Tritium Removal Facility (WTRF) is scheduled to begin operation in 2005 to reduce the amount of tritium generated in the moderator and coolant. The objective of this study is to evaluate the environmental impact of tritium released from WTRF in the postulated accident. In order to achieve this, a computer code was developed at KAIST (Korea Advanced Institute ...

For a severe PWR accident that leads to a loss of feedwater to the steam generators, such as might occur in a station blackout, fission product decay heating will cause a water boiloff. Without effective cooling of the core, steam will begin to oxidize the Zircaloy cladding. The noble gases and volatile fission products, such as Cs and I, that are major contributors to the ...

This report documents the methodology, computational framework, and results of facility accident analyses performed for the US Department of Energy (DOE) Waste Management Programmatic Environmental Impact Statement (WM PEIS). The accident sequences potentially important to human health risk are specified, their frequencies assessed, and the resultant ...

The purpose of this work was to verify the Source Term Setup Module of the Reactor Accident Program (RAP) which is used to perform environmental consequence assessments during emergency response situations at the Savannah River Site (SRS). The Source Term Setup Module is that portion of the ...

Quantifying the release of radiological source term fission products from an LMFBR reactor vessel (RV) is a necessary input to the containment analysis. To estimate this initial source term value, the distribution of the fission products and actinides inside the RV, prior to release, must be known. The in-vessel ...

A major feature of the NUREG-1150 analyses is the quantification of the uncertainties associated with the assessment of reactor accident risks, including the assessment of the uncertainties in the prediction of environmental source terms. The quantification of uncertainties was accomplished by the use of stratified sampling techniques ...

Oxidation of Zircaloy cladding is the primary source of hydrogen generated during a degraded-core accident. In this paper, reported Zircaloy oxidation rates, either measured at 1500 to 1850/sup 0/C or extrapolated from the low-temperature data obtained at 1500/sup 0/C. The results show significantly smaller oxidation and, hence, hydrogen-generation rates ...

This paper presents the results from MELCOR (Version 1.8BC) calculations of the Long-Term Station Blackout Accident Sequence, with failure to depressurize the reactor vessel, at the Peach Bottom (BWR Mark I) plant, and presents comparisons with Source Ter...

This highly technical book discusses radioactivity and the dangers it poses. The book starts with a history of radiation, then discusses ways through which radiation is transmitted in the environment and its effects on animals and humans. Sources of nuclear energy, natural and man�made, are discussed, as well as protection methods and immediate and long ...

In order to establish requirements for emergency preparedness plans at facilities licensed by the Office of Nuclear Materials Safety and Safeguards, the Nuclear Regulatory Commission (NRC) needs to develop source terms (the amount of material made airborne) in accidents. These source terms are ...

SARNET (Severe Accident Research Network) is a Network of Excellence of the EU 6. Framework Programme that integrates in a sustainable manner the research capabilities of about fifty European organisations to resolve important remaining uncertainties and safety issues concerning existing and future nuclear plant, especially water-cooled reactors, under hypothetical severe ...

This paper discusses salient aspects of severe accident related phenomenological considerations, scoping studies, and mitigative design features being studied for incorporation into a high-power research reactor plant. Key results of scoping studies on steam explosions, recriticality, core-concrete interactions, and containment transport are highlighted. Evolving design ...

Potential radiation impacts from launch of the Ulysses solar exploration experiment were evaluated using eight postulated accident scenarios. Lifetime individual dose estimates rarely exceeded 1 mrem. Most of the potential health effects would come from inhalation exposures immediately after an accident, rather than from ingestion of contaminated food or ...

Potential radiation impacts from launch of the Ulysses solar exploration experiment were evaluated using eight postulated accident scenarios. Lifetime individual dose estimates rarely exceeded 1 mrem. Most of the potential health effects would come from inhalation exposures immediately after an accident, rather than from ingestion of contaminated food or ...

An integrated risk-based approach has been developed to address the human health risks of radiological and chemical releases from potential facility accidents in support of the U.S. Department of Energy (DOE) Environmental Restoration and Waste Management (EM) Programmatic Environmental Impact Statement (PEIS). Accordingly, the facility accident analysis ...

The Spallation Neutron Source (SNS) is a Department of Energy, accelerator-based neutron source proposed for construction at the Oak Ridge National Laboratory. The project is currently nearing the end of the conceptual design stage. The objective of the target facility is to provide beams of pulsed thermal and sub-thermal neutrons for research purposes. ...

This report provides the results of source term calculations that were performed in support of the NUREG-1150 study. Severe Accident Risks: An Assessment for Five US Nuclear Power Plants.'' This is the sixth volume of a series of reports. It supplements results presented in the earlier volumes. Analyses were performed ...

Over the last decade, substantial development and progress has been made in the understanding of the nature of severe accidents and associated fission product release and transport. As part of this continuing effort, the United States Nuclear Regulatory Commission (USNRC) sponsored the development of the Source Term Code Package ...

This paper describes the new two-dimensional, four-fluid fluid dynamics and heat transfer (FLUIDS) module of the MELPROG code. MELPROG is designed to give an integrated, mechanistic treatment of pressurized water reactor (PWR) core meltdown accidents from accident initiation to vessel melt-through. The code has a modular data storage and transfer ...

A methodology, computational framework, and integrated PC-based database have been developed to assess the risks of facility accidents in support of the US Department of Energy (DOE) Environmental Restoration and Waste Management Programmatic Environmental Impact Statement. The methodology includes the following interrelated elements: (1) screening of storage and treatment ...

Accident Management Actions taken during the first days after the Chernobyl accident either proved ineffective or were not fulfilled as reported by the Soviets at the International Atomic Energy Agency Meeting of Experts in Vienna in August 1986. Most significant to source-term analyses and estimates is that it is now believed that ...

Toxicology studies can contribute much to investigations into the causes of accidents. This paper examines toxicological data from 485 fatal aircraft accidents over a 24-year period in terms of relevance to causing accidents and difficulties in procuring samples for analysis. PMID:3799566

A full-scale PRA of a DOE production reactor has been completed that considers full release of tritium as part of the severe accident source term. Two classes of postulated reactor accidents, a loss-of-moderator pumping accident and a loss-of-coolant accident, are used to ...

A full-scale PRA of a DOE production reactor has been completed that considers full release of tritium as part of the severe accident source term. Two classes of postulated reactor accidents, a loss-of-moderator pumping accident and a loss-of-coolant accident, are used to ...

The purpose of this project was to compile a bibliography of references containing environmental transuranic radionuclide data. Our intent was to identify those parameters affecting transuranic radionuclide transport that may be generic and those that may be dependent on chemical form and/or environmental conditions. An understanding of the unique characteristics and similarities between ...

The purpose of this project was to compile a bibliography of references containing environmental transuranic radionuclide data. Our intent was to identify those parameters affecting transuranic radionuclide transport that may be generic and those that may be dependent on chemical form and/or environmental conditions (i.e., site specific) in terrestrial, aquatic and atmospheric environments An ...

Four experiments are being conducted in the TREAT facility to investigate the behavior of fission products released from typical LWR fuel overheated to the point of catastrophic cladding degradation. Heatup and steam flow transients are used that simulate the conditions expected in operating power reactors undergoing various types of hypothetical severe accidents. The ...

The US Nuclear Regulatory Commission (NRC) maintains a technical training center at Chattanooga, Tennessee to provide appropriate training to both new and experienced NRC employees. This document describes a one-week course in reactor, safety concepts. The course consists of five modules: (1) historical perspective; (2) accident sequences; (3) accident ...