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All sources NASA NTRS DOE OSTI

NASA NTRS2004

Security Management and Safeguards Office

The Security Management and Safeguards Office at NASA is here to keep the people working in a safe environment. They also are here to protect the buildings and documents from sabotage, espionage, and theft. During the summer of 2004, I worked with Richard Soppet in Physical Security. While I was working here I helped out with updating the map that we currently use at NASA Glenn Research Center, attended meetings for homeland security, worked with the security guards and the locksmith. The meetings that I attended for homeland security talked about how to protect ourselves before something happened, they told us to always be on the guard and look for anything suspicious, and the different ways that terrorist groups operate. When I was with the security guards I was taught how to check someone into the base, showed how to use a radar gun, observed a security guard make a traffic stop for training and was with them while they patrolled NASA Glenn Research Center to make sure things were running smooth and no one was in danger. When I was with the lock smith I was taught how to make keys and locks for the employees here at NASA. The lock smith also showed me that he had inventory cabinets of files that show how many keys were out to people and who currently has access to the rooms that they keys were made for. I also helped out the open house at NASA Glenn Research Center. I helped out by showing the Army Reserves, and Brook Park's SWAT team where all the main events were going to take place a week before the open house was going to begin. Then during the open house I helped out by making sure people had there IDS, checked through there bags, and handed out a map to them that showed where the different activities were going to take place. So the main job here at NASA Glenn Research Center for the Security Management and Safeguards Office is to make sure that nothing is stolen, sabotaged, and espionaged. Also most importantly make sure all the employees here at NASA are in a safe environment.

Bewley, Nathaniel M.↗

DOE OSTI2012

The Next Generation Safeguards Initiative s High-Purity Uranium-233 Preservation Effort

High-purity 233U serves as a crucial reference material for accurately quantifying and characterizing uranium. The most accurate analytical results which can be obtained only with high-purity 233U certified reference material (CRM) are required when used to confirm compliance with international safeguards obligations and international nonproliferation agreements. The U.S. supply of 233U CRM is almost depleted, and existing domestic stocks of this synthetic isotope are scheduled to be down-blended for disposition with depleted uranium beginning in 2015. Down blending batches of high-purity 233U will permanently eliminate the value of this material as a CRM. Furthermore, no replacement 233U stocks are expected to be produced in the future due to a lack of operating production capability and the high cost of replacing such capability. Therefore, preserving select batches of high-purity 233U is of great value and will assist in retaining current analytical capabilities for uranium-bearing samples. Any organization placing a priority on accurate results of uranium analyses, or on the confirmation of trace uranium in environmental samples, has a vested interest in preserving this material. This paper describes the need for high-purity 233U, the consequences organizations and agencies face if this material is not preserved, and the progress and future plans for preserving select batches of the purest 233U materials from disposition. This work is supported by the Next Generation Safeguards Initiative, Office of Nonproliferation and International Security, National Nuclear Security Administration.

Certified Reference Material↗

DOE OSTI2012

Spiral Development for Safeguards Instrumentation

Safeguards instrumentation is highly specialized, so a common approach in the US has been to develop initial prototypes for performance, operability and security within the US National Laboratories for the IAEA and then seek one or more commercial partners. Transfer of technology from US National Laboratories is a legal requirement for products that have the potential for mass production. Other important objectives include minimizing time to deployment and lifecycle cost, and optimizing product maintainability, sustainability and manufacturability. Unfortunately, the deployment of systems developed via this model has sometimes been seriously delayed or never adopted because of the difficulty of optimizing the significant parameters of the process between the public and private sectors. The authors suggest that forming an R&D partnership between a research laboratory and a commercial company much earlier in the process would provide significant advantages. The present US practice leads to unnecessary expenditures during the early R&D phase since many decisions are made based on research needs that are counterproductive for commercialization and manufacturability. If the ultimate goal of the project is to produce a reliable and cost effective commercial product, the commercial input is needed early and often. The new “model” of developing systems in a closer collaboration with the private sector, in a spiral “Commercialization by Design” approach, should also limit the long term financial mortgages that Member States frequently experience with respect to safeguards instrumentation development using the present process. As a concrete example, the potential for incorporating Wire Integrity Verification Technology into the iCobra Reader System is discussed.

Koskelo, M.↗

DOE OSTI2013

Electrochemically Modulated Separation for Plutonium Safeguards

Accurate and timely analysis of plutonium in spent nuclear fuel is critical in nuclear safeguards for detection of both protracted and rapid plutonium diversions. Gamma spectroscopy is a viable method for accurate and timely measurements of plutonium provided that the plutonium is well separated from the interfering fission and activation products present in spent nuclear fuel. Electrochemically modulated separation (EMS) is a method that has been used successfully to isolate picogram amounts of Pu from nitric acid matrices. With EMS, Pu adsorption may be turned "on" and "off" depending on the applied voltage, allowing for collection and stripping of Pu without the addition of chemical reagents. In this work, we have scaled up the EMS process to isolate microgram quantities of Pu from matrices encountered in spent nuclear fuel during reprocessing. Several challenges have been addressed including surface area limitations, radiolysis effects, electrochemical cell performance stability, and chemical interferences. After these challenges were resolved, 6 µg Pu was deposited in the electrochemical cell with approximately an 800-fold reduction of fission and activation product levels from a spent nuclear fuel sample. Modeling showed that these levels of Pu collection and interference reduction may not be sufficient for Pu detection by gamma spectroscopy. The main remaining challenges are to achieve a more complete Pu isolation and to deposit larger quantities of Pu for successful gamma analysis of Pu. If gamma analyses of Pu are successful, EMS will allow for accurate and timely on-site analysis for enhanced Pu safeguards.

Pratt, Sandra H.↗

DOE OSTI2015

Organizational Culture for Safety, Security, and Safeguards in New Nuclear Power Countries

This chapter will contain the following sections: Existing international norms and standards for developing the infrastructure to support new nuclear power programs The role of organizational culture and how it supports the safe, secure, and peaceful application of nuclear power Identifying effective and efficient strategies for implementing safety, security and safeguards in nuclear operations Challenges identified in the implementation of safety, security and safeguards Potential areas for future collaboration between countries in order to support nonproliferation culture

Kovacic, Donald N↗

DOE OSTI2018

SafeGuards Analysis

The SafeGuards Analysis (SGA) toolkit is an add-on to existing fuel cycle codes that provides safeguards measurement and evaluation modeling capabilities with associated uncertainty quantification and sensitivity analysis techniques. An important feature of the SGA toolbox is that any other fuel cycle or facility-level code (such as VISION, CYCLUS, et al.) can be easily modified to work with SGA. Thus SGA can incorporate any of the other available fuel cycle codes with minimal modification.

Shugart, Nicolas↗

DOE OSTI2022

A Tool Kit for Generating Simulated Radiation Measurements for Advanced Reactor Safeguards and Security

A tool kit was developed to simulate and analyze passive radiation measurements of molten salt reactor (MSR) operations to support development of nuclear safeguards approaches for this emerging reactor technology. A Transient Simulation Framework of Reconfigurable Modules (TRANSFORM) multiphysics simulation of an MSR produces time-dependent isotopic inventories at user-selected locations within the model. The tool kit implements the Gamma Detector Response and Analysis Software (GADRAS) application programming interface to inject the TRANSFORM isotopic inventories extracted/processed by a Python pipeline into GADRAS models of user-defined geometries. The TRANSFORM inventories are the source terms used to obtain synthetic measurements from GADRAS-defined detectors. The speed of TRANSFORM and GADRAS simulations enables surveying the large design space of MSRs (e.g., fuel type, fuel salt composition, number of loops) and the plethora of measurements (e.g., location, detector type, and collimation) within the reactor. This has enabled timely assessment of the various measurement locations and detectors to identify the most effective and efficient safeguards approach for a specific MSR design. Lastly, the tool kit also simulates extracted samples that can be aged to a desired dose, enabling stakeholders to optimize a measurement plan to use sample analysis as an element within a broader material accountancy plan.

Westphal, Greg↗

DOE OSTI2020

Leveraging Machine Learning Capabilities for the Characterization of Irradiated Uranium: A Case Study of Analysis Methods for Nuclear Safeguards and Nuclear Forensics

Nondestructively determining the initial enrichment of irradiated uranium is a complex and laborious multivariable problem due to the presence of fission products. This work demonstrates the capabilities of machine learning to analyze gamma-ray spectral data to determine initial enrichment without knowledge of the decay time of the sample. The approach developed is agnostic to the particular scenario and is applicable to a wide variety of applications in nuclear forensics and nuclear safeguards. We irradiated 5 mg uranium standard reference materials at discrete enrichment values ranging from 0.02% to 97% 235 U (weight percent) in UT Austin’s Nuclear Engineering Teaching Laboratory TRIGA Mark II 1.1 MW research reactor, allowed each to decay for 8 hours, and then measured each sample via gamma-ray spectrometry for 50 hours post-irradiation yielding 1,400 individual gamma-ray spectra discretized into 8,192 energy bins. We then trained decision trees models to analyze individual gamma-ray spectra and estimate the associated initial enrichment without knowledge of the time since end of irradiation. We evaluated the performance of the models with a reserved test set not used for training or calibrating the model. A decision tree model constructed with this procedure achieved a mean absolute error in initial enrichment determination of 2.3% (weight percent 235 U). Next, we implemented a principal component analysis pre-processing routine of the gamma-ray spectrometry data to reduce the dimensionality of the dataset from 8,192 channels in the spectrum to 10 principal components while retaining over 99% of the inherent variance in the data. Decision tree models constructed with these data demonstrated decreased mean absolute error in enrichment determination, reduced computational time, and decreased complexity. A single decision tree model constructed with this procedure achieved a mean absolute error in initial enrichment determination of 0.05% (weight percent 235 U). Furthermore, we analyzed these models with learning curves to ensure that overfitting did not occur. The capabilities provided by these models can be naturally extended to other application-focused measurements in the fields of nuclear safeguards, nuclear forensics, and nuclear non-proliferation.

Drescher, Adam↗

DOE OSTI2012

Safeguards Issues at Nuclear Reactors and Enrichment Plants [Slides]

The Agency's safeguards technical objective is the timely detection of diversion of significant quantities of nuclear material from peaceful nuclear activities to the manufacture of nuclear weapons or of other nuclear explosive devices or for purposes unknown, and deterrence of such diversion by the risk of early detection.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2015

High-Efficiency CdZnTe Position-Sensitive VFG Gamma-Ray Detectors for Safeguards Applications

The goal of this project is to incorporate a Cadmium-Zinc-Telluride (CdZnTe or CZT) detector (with 1% or better resolution) into a bench-top prototype for isotope identification and related safeguards applications. The bench-top system is based on a 2x2 array of 6x6x20 mm 3 position-sensitive virtual Frisch-grid (VFG) CZT detectors. The key features of the array are that it allows for the use of average-grade CZT material with a moderate content of defects, and yet it provides high energy resolution, 1% FWHM at 662 keV, large effective area, and low-power consumption. The development of this type of 3D detector and new instruments incorporating them is motivated by the high cost and low availability of large, > 1 cm 3 , CZT crystals suitable for making multi-pixel detectors with acceptable energy resolution and efficiency.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2012

Strengthened IAEA Safeguards-Imagery Analysis: Geospatial Tools for Nonproliferation Analysis

This slide presentation focuses on the growing role and importance of imagery analysis for IAEA safeguards applications and how commercial satellite imagery, together with the newly available geospatial tools, can be used to promote 'all-source synergy.' As additional sources of openly available information, satellite imagery in conjunction with the geospatial tools can be used to significantly augment and enhance existing information gathering techniques, procedures, and analyses in the remote detection and assessment of nonproliferation relevant activities, facilities, and programs. Foremost of the geospatial tools are the 'Digital Virtual Globes' (i.e., GoogleEarth, Virtual Earth, etc.) that are far better than previously used simple 2-D plan-view line drawings for visualization of known and suspected facilities of interest which can be critical to: (1) Site familiarization and true geospatial context awareness; (2) Pre-inspection planning; (3) Onsite orientation and navigation; (4) Post-inspection reporting; (5) Site monitoring over time for changes; (6) Verification of states site declarations and for input to State Evaluation reports; and (7) A common basis for discussions among all interested parties (Member States). Additionally, as an 'open-source', such virtual globes can also provide a new, essentially free, means to conduct broad area search for undeclared nuclear sites and activities - either alleged through open source leads; identified on internet BLOGS and WIKI Layers, with input from a 'free' cadre of global browsers and/or by knowledgeable local citizens (a.k.a.: 'crowdsourcing'), that can include ground photos and maps; or by other initiatives based on existing information and in-house country knowledge. They also provide a means to acquire ground photography taken by locals, hobbyists, and tourists of the surrounding locales that can be useful in identifying and discriminating between relevant and non-relevant facilities and their associated infrastructure. The digital globes also provide highly accurate terrain mapping for better geospatial context and allow detailed 3-D perspectives of all sites or areas of interest. 3-D modeling software (i.e., Google's SketchUp6 newly available in 2007) when used in conjunction with these digital globes can significantly enhance individual building characterization and visualization (including interiors), allowing for better assessments including walk-arounds or fly-arounds and perhaps better decision making on multiple levels (e.g., the best placement for International Atomic Energy Agency (IAEA) video monitoring cameras).

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

DOE OSTI2020

A highly-enriched 244 Pu reference material for nuclear safeguards and nuclear forensics measurements

A highly-enriched 244 Pu isotope dilution reference material has been prepared and characterized for metrologically traceable measurements of very small quantities of plutonium. The amount of plutonium in samples associated with nuclear safeguards and nuclear forensic measurements can be significantly less than 1 ng. Accordingly, the ability to quantify the amount and isotopic composition of plutonium from a single mass-spectrometric analysis is particularly desirable. The highly-enriched 244 Pu reference material, described here, will minimize the magnitude of spike corrections necessary to obtain accurate information on plutonium isotopic composition from isotope dilution measurements.

07 ISOTOPE AND RADIATION SOURCES↗

DOE OSTI2022

High bias machine learning for antineutrino-based safeguards for small reactors

The statistical methods used for antineutrino detection will need to be improved to effectively monitor the inventory of next-generation nuclear reactors. In this sensitivity study, we evaluate machine learning models compared to previously used statistical approaches to identify diversion scenarios in a simulated Advanced Fast Reactor (AFR)-100. A chi-square goodness-of-fit technique, which individually compares the simulated antineutrino yields to the expected antineutrino yield, resulted in precise but low diversion detection probability. Various support vector machine (SVM) models were applied with diverse training datasets to evaluate the robustness of the method towards unexpected or “unseen” diversion scenarios. Furthermore, our results indicate that while the SVM models significantly improved the detection probability of near-field antineutrino-based safeguards, up to a probability of ~0.04, for the simulated small reactor, the detection system still needs improvements to reach the 0.2 detection limit established by the International Atomic Energy Agency.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

DOE OSTI2018

Characterization of a large-area iQID imager for safeguards applications

Environmental sampling and sample analyses by the International Atomic Energy Agency is a key method for verifying declarations in international safeguards agreements. Quantitative Digital Autoradiography for Environmental Samples is a system developed by Pacific Northwest National Laboratory to examine environmental swipe samples (ESS) prior to subsequent, destructive analysis. This approach is passive and noninvasive for imaging beta and gamma emissions, which transmit through the plastic bags containing the ESS. Alpha particle imaging is also possible with different ESS containers. This technology is based on a portable, real-time, event-counting, high spatial resolution system called iQID (ionizing-radiation Quantum Imaging Detector), which is made from commercial, off-the-shelf components. This includes a scintillator in direct contact with a micro-channel plate image intensifier and a lens for imaging the intensified scintillation events onto a CCD/CMOS camera. The QDARES large-area iQID includes a fiber-optic taper coupled to the image intensifier which increases the imaging area to a ~100 cm square with a 105 mm x 105 mm taper. In this study, we describe new characterization results, including spatial resolution, energy response, minimum detectable activity for several isotopes, detector uniformity, and count-rate capability.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

DOE OSTI2025

Validation and demonstration of the AEFC as a practical safeguards tool for inventory verification

The Advanced Experimental Fuel Counter (AEFC) is a nondestructive assay (NDA) instrument designed to determine the residual fissile mass in irradiated fuel assemblies for safeguards verification purposes. This is done by actively interrogating an assembly with a neutron source and measuring the total (Singles) and correlated (Doubles) neutron count rates resulting from induced fissions in the irradiated nuclear fuel and relating those rates to the residual fissile mass using calibration curves. Comprehensive NDA measurements of the irradiated fuel inventory at Israeli Research Reactor 1 (IRR-1) were taken with the AEFC to validate a set of previously developed calibration curves. During the campaign, measurements were acquired of 32 standard fuel assemblies and three control assemblies in just nine days. This is a significant majority of the research reactor's irradiated fuel inventory and the largest data set gathered by the AEFC to date. Many of the fuel assemblies measured during the campaign had much shorter cooling times than those assemblies previously measured with the instrument. Calibration curves developed from previous AEFC deployments were used to determine the residual 235 U mass in the measured standard fuel assemblies. The results of the campaign demonstrated that the AEFC can be used to estimate the 235 U mass remaining in a large number of irradiated fuel assemblies with 1%–5% uncertainty in a reasonable amount of time despite operating in a high dose environment.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

DOE OSTI2012

Modeling of UF{sub 6} enrichment with gas centrifuges for nuclear safeguards activities

The physical modeling of uranium isotopes ({sup 235}U, {sup 238}U) separation process by centrifugation of is a key aspect for predicting the nuclear fuel enrichment plant performances under surveillance by the Nuclear Safeguards Authorities. In this paper are illustrated some aspects of the modeling of fast centrifuges for UF{sub 6} gas enrichment and of a typical cascade enrichment plant with the Theoretical Centrifuge and Cascade Simulator (TCCS). The background theory for reproducing the flow field characteristics of a centrifuge is derived from the work of Cohen where the separation parameters are calculated using the solution of a differential enrichment equation. In our case we chose to solve the hydrodynamic equations for the motion of a compressible fluid in a centrifugal field using the Berman - Olander vertical velocity radial distribution and the solution was obtained using the Matlab software tool. The importance of a correct estimation of the centrifuge separation parameters at different flow regimes, lies in the possibility to estimate in a reliable way the U enrichment plant performances, once the separation external parameters are set (feed flow rate and feed, product and tails assays). Using the separation parameters of a single centrifuge allow to determine the performances of an entire cascade and, for this purpose; the software Simulink was used. The outputs of the calculation are the concentrations (assays) and the flow rates of the enriched (product) and depleted (tails) gas mixture. These models represent a valid additional tool, in order to verify the compliance of the U enrichment plant operator declarations with the 'on site' inspectors' measurements.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2012

A few Los Alamos Nuclear Safeguards stories and other things [Slides]

Two very different nuclear material safeguard missions will be briefly described to give the audience a feel for the type of work carried out by physicists at the Los Alamos National Laboratory. I will show how transit-state theory can be used to derive black-body radiation and the escape of particles from an ideal gas. Understanding these simple processes can led to a better understanding of how transit-state theory should be applied in the theory of nuclear reactions. Finally I will show a few photos to give a feel for some of the other missions conducted by Los Alamos.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2013

Precision Information Environment (PIE) for International Safeguards: Pre-Demonstration Development Use Cases

In FY2013, the PIE International Safeguards team demonstrated our development progress to U.S. Department of Energy (DOE) staff from the Office of Nonproliferation and International Security (NA-24, our client) and the Office of Defense Nuclear Nonproliferation Research and Development (NA-22). Following the demonstration, the team was asked by our client to complete additional development prior to a planned demonstration at the International Atomic Energy Agency (IAEA), scheduled tentatively for January or spring of 2014. The team discussed four potential areas for development (in priority order), and will develop them as time and funding permit prior to an IAEA demonstration. The four capability areas are: 1. Addition of equipment manuals to PIE-accessible files 2. Optical character recognition (OCR) of photographed text 3. Barcode reader with information look-up from a database 4. Add Facilities to Data Model 5. Geospatial capabilities with information integration Each area will be described below in a use case.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗