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An optimized international vehicle monitor

Description: The security plans for many DOE facilities require the monitoring of pedestrians and vehicles to control the movement of special nuclear material (SNM). Vehicle monitors often provide the outer-most barrier against the theft of SNM. Automatic monitors determine the presence of SNM by comparing the gamma-ray and neutron intensity while occupied, to the continuously updated background radiation level which is measured while the unit is unoccupied. The most important factors in choosing automatic vehicle monitors are sensitivity, cost and in high traffic applications total monitoring time. The two types of automatic vehicle monitors presently in use are the vehicle monitoring station and the drive-through vehicle monitor. These two types have dramatically different cost and sensitivities. The vehicle monitoring station has a worst-case detection sensitivity of 40 g of highly enriched uranium, HEU, and a cost approximately $180k. This type of monitor is very difficult to install and can only be used in low traffic flow locations. The drive-through vehicle portal has a worst-case detection sensitivity of 1 kg of HEU and a cost approximately $20k. The world`s political situation has created a pressing need to prevent the diversion of SNM from FSU nuclear facilities and across international borders. Drive-through vehicle monitors would be an effective and practical nuclear material proliferation deterrent if their sensitivity can be improved to a sufficient level. The goal of this project is to evaluate different detector configurations as a means of improving the sensitivity of these instruments to achieve a vehicle monitor that is economical, practical to install, and has adequate sensitivity to be an effective barrier to illegal transportation of SNM.
Date: March 1, 1997
Creator: York, R.L.; Close, D.A. & Fehlau, P.E.
Partner: UNT Libraries Government Documents Department

A design methodology for unattended monitoring systems

Description: The authors presented a high-level methodology for the design of unattended monitoring systems, focusing on a system to detect diversion of nuclear materials from a storage facility. The methodology is composed of seven, interrelated analyses: Facility Analysis, Vulnerability Analysis, Threat Assessment, Scenario Assessment, Design Analysis, Conceptual Design, and Performance Assessment. The design of the monitoring system is iteratively improved until it meets a set of pre-established performance criteria. The methodology presented here is based on other, well-established system analysis methodologies and hence they believe it can be adapted to other verification or compliance applications. In order to make this approach more generic, however, there needs to be more work on techniques for establishing evaluation criteria and associated performance metrics. They found that defining general-purpose evaluation criteria for verifying compliance with international agreements was a significant undertaking in itself. They finally focused on diversion of nuclear material in order to simplify the problem so that they could work out an overall approach for the design methodology. However, general guidelines for the development of evaluation criteria are critical for a general-purpose methodology. A poor choice in evaluation criteria could result in a monitoring system design that solves the wrong problem.
Date: March 1, 2000
Partner: UNT Libraries Government Documents Department

A flexible method for multi-level sample size determination

Description: This paper gives a flexible method to determine sample sizes for both systematic and random error models (this pertains to sampling problems in nuclear safeguard questions). In addition, the method allows different attribute rejection limits. The new method could assist achieving a higher detection probability and enhance inspection effectiveness.
Date: April 1, 1997
Creator: Lu, Ming-Shih; Sanborn, J.B. & Teichmann, T.
Partner: UNT Libraries Government Documents Department

Geolocation and route attribution in illicit trafficking of nuclear materials

Description: We present a matrix of 60 possible forensic tools. If the specifics of the types of materials and analytical techniques are included, the number becomes vastly greater. Accordingly, the prioritization and discretion is addressed that should be utilized to select the most useful tools.
Date: April 1, 1999
Creator: Hutcheon, I & Niemeyer, S
Partner: UNT Libraries Government Documents Department

Quantitative evaluation of the RETIMAC system

Description: One means of raising the degree of protection afforded strategic special nuclear materials against theft and diversion is the installation of Real Time Material Control (RETIMAC) systems. The ability of RETIMAC to detect any covert attempt to steal special nuclear materials in a time frame that is adequate to contain subcritical quantities of special nuclear material within the boundaries of the material protection system and to maintain current knowledge of the quantity and location of all strategic special nuclear material was tested. A commercial-scale mixed oxide fuel fabrication plant was chosen for the study. (LK)
Date: June 10, 1975
Creator: Bain, E.E.; Fisher, R.H.; Gozani, T.; Harris, L. Jr.; Kendrick, H.; Kull, L.A. et al.
Partner: UNT Libraries Government Documents Department

Techniques and methods in nuclear materials traceability

Description: The nonproliferation community is currently addressing concerns that the access to special nuclear materials may increase the illicit trafficking in weapons-usable materials from civil and/or weapons material stores and/or fuel cycles systems. Illicit nuclear traffic usually involves reduced quantities of nuclear materials perhaps as samplings of a potential protracted diversionary flow from sources to users. To counter illicit nuclear transactions requires the development of techniques and methods in nuclear material traceability as an important phase of a broad forensic analysis capability. This report discusses how isotopic signatures and correlation methods were applied to determine the origins of Highly Enriched Uranium (HEU) and Plutonium samples reported as illicit trafficking in nuclear materials.
Date: August 1, 1996
Creator: Persiani, P.J.
Partner: UNT Libraries Government Documents Department

Technical description of candidate fluorescence compounds and radioisotopes for a nuclear smuggling deterrence tag (IL500E)

Description: This report summarizes the efforts completed in identifying candidate fluorescence compounds and radioisotopes for a developing tagging system. The tagging system is being developed as a deterrent to nuclear smuggling, by providing a means of: (1) tracing materials and pilferers to the facility of origin for any recovered special nuclear materials; (2) inventory control of long-term stored items containing special nuclear materials; and (3) tracking materials transferred between facilities. The tagging system uses four types of tagging materials to cover a range of applications intended to prevent the pilfering of special nuclear materials. One material, fluorescent compounds which are invisible without ultraviolet or near-infrared detection systems, is marked on controlled items with a tracking pattern that corresponds to a specified item in a specified location in the data control system. The tagging system uses an invisible, fluorescent dusting powder to mark equipment and personnel who inappropriately handle the tagged material. The tagging system also uses unique combinations of radionuclides to identify the facility of origin for any special nuclear material. Currently, 18 long-lived radioisotopes, 38 short-live radioisotopes and 10 fluorescent compounds have been selected as candidate materials for the tagging system.
Date: March 1, 1996
Creator: Hartenstein, S. D. & Aryaeinejad, R.
Partner: UNT Libraries Government Documents Department

An integrated approach for multi-level sample size determination

Description: Inspection procedures involving the sampling of items in a population often require steps of increasingly sensitive measurements, with correspondingly smaller sample sizes; these are referred to as multilevel sampling schemes. In the case of nuclear safeguards inspections verifying that there has been no diversion of Special Nuclear Material (SNM), these procedures have been examined often and increasingly complex algorithms have been developed to implement them. The aim in this paper is to provide an integrated approach, and, in so doing, to describe a systematic, consistent method that proceeds logically from level to level with increasing accuracy. The authors emphasize that the methods discussed are generally consistent with those presented in the references mentioned, and yield comparable results when the error models are the same. However, because of its systematic, integrated approach the proposed method elucidates the conceptual understanding of what goes on, and, in many cases, simplifies the calculations. In nuclear safeguards inspections, an important aspect of verifying nuclear items to detect any possible diversion of nuclear fissile materials is the sampling of such items at various levels of sensitivity. The first step usually is sampling by ``attributes`` involving measurements of relatively low accuracy, followed by further levels of sampling involving greater accuracy. This process is discussed in some detail in the references given; also, the nomenclature is described. Here, the authors outline a coordinated step-by-step procedure for achieving such multilevel sampling, and they develop the relationships between the accuracy of measurement and the sample size required at each stage, i.e., at the various levels. The logic of the underlying procedures is carefully elucidated; the calculations involved and their implications, are clearly described, and the process is put in a form that allows systematic generalization.
Date: December 31, 1997
Creator: Lu, M.S.; Teichmann, T. & Sanborn, J.B.
Partner: UNT Libraries Government Documents Department

Nondestructive assay tests of high-efficiency neutron counter (HENC) for waste assay and possible diversion scenario

Description: An advanced passive neutron counter, the high-efficiency neutron counter (HENC), has been used to measure plutonium content in 200-L waste drums. The HENC was designed with the {sup 252}Cf add-a-source (AS) feature to improve accuracy over a wide range of waste matrix materials. The current implementation allows for passive neutron coincidence counting, AS analysis, and multiplicity analysis. Passive neutron assay of typical waste containers is intrinsically more accurate than active neutron techniques because of the penetrability of the spontaneous fission neutrons originating from within the waste matrix. In addition, the HENC is designed as a slightly undermoderated detector to be less sensitive to low loading of hydrogen-bearing matrices. The following paper considers the applicability of three different nondestructive assay methods for analysis of waste drums and the flagging of possible diversions in waste drums. The {sup 252}Cf AS method, multiplicity counting, and a bounded-parameter multiplicity analysis are presented with areas of applicability.
Date: May 1, 1998
Creator: Mayo, D.R.; Menlove, H.O. & Pecos, J.M.
Partner: UNT Libraries Government Documents Department

Technologies for detection of nuclear materials

Description: Detection of smuggled nuclear materials at transit points requires monitoring unknown samples in large closed packages. This review contends that high-confidence nuclear-material detection requires induced fission as the primary mechanism, with passive radiation screening in a complementary role. With the right equipment, even small quantities of nuclear materials are detectable with a high probability at transit points. The equipment could also be linked synergistically with detectors of other contrabond. For screening postal mail and packages, passive monitors are probably more cost-effective. When a suspicious item is detected, a single active probe could then be used. Until active systems become mass produced, this two-stage screening/interrogation role for active/passive equipment is more economic for cargo at border crossings. For widespread monitoring of nuclear smuggling, it will probably be necessary to develop a system for simultaneously detecting most categories of contraband, including explosives and illicit drugs. With control of nuclear materials at known storage sites being the first line of defense, detection capabilities at international borders could establish a viable second line of defense against smuggling.
Date: March 30, 1996
Creator: DeVolpi, A.
Partner: UNT Libraries Government Documents Department

Capability of environmental sampling to detect undeclared cask openings

Description: The goal of this study is to determine the signatures that would allow monitors to detect diversion of nuclear fuel (by a diverter) from a storage area such as a geological repository. Due to the complexity of operations surrounding disposal of spent nuclear fuel in a geologic repository, there are several places that a diversion of fuel could take place. After the canister that contains the fuel rods is breached, the diverter would require a hot cell to process or repackage the fuel. A reference repository and possible diversion scenarios are discussed. When a canister is breached, or during reprocessing to extract nuclear weapons material (primarily Pu), several important isotopes or signatures including tritium, {sup 85}Kr, and {sup 129}I are released to the surrounding environment and have the potential for analysis. Estimates of release concentrations of the key signatures from the repository under a hypothetical diversion scenario are presented and discussed. Gas analysis data collected from above-ground storage casks at Idaho National Engineering and Environmental Laboratory (INEEL) Test Area North (TAN) are included and discussed in the report. In addition, LANL participated in gas sampling of one TAN cask, the Castor V/21, in July 1997. Results of xenon analysis from the cask gas sample are presented and discussed. The importance of global fallout and recent commercial reprocessing activities and their effects on repository monitoring are discussed. Monitoring and instrumental equipment for analysis of the key signature isotopes are discussed along with limits of detection. A key factor in determining if diversion activities are in progress at a repository is the timeliness of detection and analysis of the signatures. Once a clandestine operation is suspected, analytical data should be collected as quickly as possible to support any evidence of diversion.
Date: December 1, 1997
Creator: Beckstead, L.W.; Efurd, D.W.; Hemberger, P.H.; Abhold, M.E. & Eccleston, G.W.
Partner: UNT Libraries Government Documents Department

Safeguard and security issues for the U.S. Fissile Materials Disposition Program

Description: The Department of Energy`s Office of Materials Disposition (MD) is analyzing long-term storage and disposition options for fissile materials, preparing a Programmatic Environmental Impact Statement (PEIS), preparing for a Record of Decision (ROD) regarding this material, and conducting other related activities. A primary objective of this program is to support U.S. nonproliferation policy by reducing major security risks. Particular areas of concern are the acquisition of this material by unauthorized persons and preventing the reintroduction of the material for use in weapons. This paper presents some of the issues, definitions, and assumptions addressed by the Safeguards and Security Project Team in support of the Fissile Materials Disposition Program (FMDP). The discussion also includes some preliminary ideas regarding safeguards and security criteria that are applicable to the screening of disposition options.
Date: September 1, 1995
Creator: Jaeger, C.D.; Moya, R.W. & Duggan, R.A.
Partner: UNT Libraries Government Documents Department

Linear filtering applied to safeguards of nuclear material

Description: In regard to the problem of nuclear materials theft or diversion in the fuel cycle, a method is needed to detect continual thefts of relatively small amounts of material. It is suggested that Kalman filtering techniques be used. A hypothetical material flow situation is used to illustrate the technique; losses could be detected in as few as 5 months. (DLC)
Date: January 1, 1975
Creator: Pike, D.H.; Morrison, G.W. & Holland, C.W.
Partner: UNT Libraries Government Documents Department

Applications of Kalman Filtering to nuclear material control. [Kalman filtering and linear smoothing for detecting nuclear material losses]

Description: The feasibility of using modern state estimation techniques (specifically Kalman Filtering and Linear Smoothing) to detect losses of material from material balance areas is evaluated. It is shown that state estimation techniques are not only feasible but in most situations are superior to existing methods of analysis. The various techniques compared include Kalman Filtering, linear smoothing, standard control charts, and average cumulative summation (CUSUM) charts. Analysis results indicated that the standard control chart is the least effective method for detecting regularly occurring losses. An improvement in the detection capability over the standard control chart can be realized by use of the CUSUM chart. Even more sensitivity in the ability to detect losses can be realized by use of the Kalman Filter and the linear smoother. It was found that the error-covariance matrix can be used to establish limits of error for state estimates. It is shown that state estimation techniques represent a feasible and desirable method of theft detection. The technique is usually more sensitive than the CUSUM chart in detecting losses. One kind of loss which is difficult to detect using state estimation techniques is a single isolated loss. State estimation procedures are predicated on dynamic models and are well-suited for detecting losses which occur regularly over several accounting periods. A single isolated loss does not conform to this basic assumption and is more difficult to detect.
Date: October 1, 1977
Creator: Pike, D.H.; Morrison, G.W. & Westley, G.W.
Partner: UNT Libraries Government Documents Department

Enhancement of loss detection capability using a combination of the Kalman Filter/Linear Smoother and controllable unit accounting approach

Description: An approach to loss detection is presented which combines the optimal loss detection capability of state estimation techniques with a controllable unit accounting approach. The state estimation theory makes use of a linear system model which is capable of modeling the interaction of various controllable unit areas within a given facility. An example is presented which illustrates the increase in loss detection probability which is realizable with state estimation techniques. Comparisons are made with a Shewhart Control Chart and the CUSUM statistic.
Date: January 1, 1979
Creator: Pike, D. H. & Morrison, G. W.
Partner: UNT Libraries Government Documents Department

Aggregated systems model: a tool for nuclear safeguards decision-making

Description: Setting performance criteria for systems that safeguard special nuclear material (SNM) involves many considerations: characteristics of adversaries attempting to divert SNM, safeguards response to attempts, costs of safeguards systems, and the consequences of diverted SNM. This paper describes an Aggregated Systems Model which is designed to assist decision makers integrate and evaluate consistently these diverse factors. Results from applying the model to a hypothetical facility handling SNM are summarized. The paper also describes a new performance criterion designed to measure the effectiveness of a safeguard system in deterring adversaries.
Date: October 4, 1979
Creator: Al-Ayat, R.; Judd, B. & Huntsman, J.
Partner: UNT Libraries Government Documents Department

Goals of measurement systems for international safeguards

Description: The safeguards applied by the International Atomic Energy Agency are based on technical performance goals and criteria that have been developed, but not officially adopted by the Agency. The goals derive in part from the external consequences that safeguards are intended to prevent and in some cases on internal considerations of feasibility. To the extent that these goals may not be attainable, as may be the case with large-throughput bulk reprocessing plants, the Agency is placed in a difficult position. In this paper safeguards goals and criteria and their underlying rationales are critically examined. Suggestions for a more rational and workable structure of performance goals are offered.
Date: January 1, 1979
Creator: de Montmollin, J.M. & Weinstock, E.V.
Partner: UNT Libraries Government Documents Department

Enhanced safeguards via solution monitoring

Description: Solution monitoring is defined as the essentially continuous monitoring of solution level, density, and temperature in all tanks in the process that contain, or could contain, safeguards-significant quantities of nuclear material. This report describes some of the enhancements that solution monitoring could make to international safeguards. The focus is on the quantifiable benefits of solution monitoring, but qualitatively, solution monitoring can be viewed as a form of surveillance. Quantitatively, solution monitoring can in some cases improve diversion detection probability. For example, the authors show that under certain assumptions, solution monitoring can be used to reduce the standard deviation of the annual material balance, {sigma}{sub MB}, from approximately 17 kg to approximately 4 kg. Such reduction in {sigma}{sub MB} will not always be possible, as they discuss. However, in all cases, solution monitoring would provide assurance that the measurement error models are adequate so that one has confidence in his estimate of {sigma}{sub MB}. Some of the results in this report were generated using data that were simulated with prototype solution monitoring software that they are developing. An accompanying document describes that software.
Date: September 1, 1996
Creator: Burr, T. & Wangen, L.
Partner: UNT Libraries Government Documents Department

Nuclear materials safeguards for the future

Description: Basic concepts of domestic and international safeguards are described, with an emphasis on safeguards systems for the fuel cycles of commercial power reactors. Future trends in institutional and technical measures for nuclear materials safeguards are outlined. The conclusion is that continued developments in safeguards approaches and technology, coupled with institutional measures that facilitate the global management and protection of nuclear materials, are up to the challenge of safeguarding the growing inventories of nuclear materials in commercial fuel cycles in technologically advanced States with stable governments that have signed the nonproliferation treaty. These same approaches also show promise for facilitating international inspection of excess weapons materials and verifying a fissile materials cutoff convention.
Date: December 31, 1995
Creator: Tape, J.W.
Partner: UNT Libraries Government Documents Department