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DOE OSTI2016

The Interface of Safety and Security in Transport: A Regional Perspective

Security of nuclear and other radioactive material in transport continues to be a challenge for States that are working on strengthening their nuclear security regime. One reason for this is that State regulatory agencies and other organizations lack the resources and trained personnel to dedicate to this field. For over 50 years safety has been a major focus in the use, storage and transport of radioactive material. Only recently, since the late 1990s, has dedicated focus been given to the field of security. One way to assist States to advance nuclear security is to reach out to safety workers (regulators, inspectors, and safety compliance personnel) and showcase the need to better integrate safety and security practices. A recent IAEA regional workshop in Bangkok, Thailand (June 2015) yielded profound results when subject matter experts lectured on both the safety and the security of radioactive material in transport. These experts presented and discussed experiences and best practices for: 1) developing and implementing safety requirements and security recommendations for radioactive material in transport; 2) national and international cooperation; and 3) preventing shipment delays/denials of radioactive material. The workshop participants, who were predominantly from safety organizations, shared that they received the following from this event: 1. A clear understanding of the objectives of the IAEA safety requirements and security recommendations for radioactive material in transport. 2. A general understanding of and appreciation for the similarities and differences between safety requirements and security recommendations for radioactive material in transport. 3. A greater appreciation of the interface between transport safety and security and potential impacts of this interface on the efforts to strengthen the compliance assurance regime for the safe transport of radioactive material. 4. A general understanding of assessing the transport security scenarios and developing transport security plans. Many participants also reported their appreciation of the workshop exercises that specifically focused on practical aspects of safety and security of transport of radioactive material. These workshop outcomes highlight the important role professionals can offer when they receive additional safety training and education for radioactive material in transport. Moreover, these professionals can help to increase capacity in countries with developing nuclear security regimes. This paper explores workshop outcomes and transportation regulations and guidelines for radioactive material.

Welch, Tim↗

DOE OSTI2016

Investigating the Depth of Penetration of Radionuclides in Concrete - 16292

This paper focuses on some chemical and structural aspects for mature concrete structural substrate that functions as a barrier to radioactive material migration. Exposure to radioactive material may be a consequence of surface contact, such as resulting from exposure by spills or leaks. In properly-prepared waste storage areas, undamaged paint and sealant helps to protect the structural cement. However, damaged surfaces, cracks, and relatively porous slab seams can offer a preferred migration pathway for spilled contaminates, including radionuclides. The cost of remediation of concrete structures is directly related to the amount of concrete that must be removed and subsequently disposed. A carefully implemented investigative plan can be utilized to determine how much concrete must be removed and the approximate level of volumetric radiological contamination can be used to estimate disposal costs. Normal concrete pore solution is saturated with calcium hydroxide and also contains sodium and potassium hydroxide; the pH is typically 13 to 14. Contaminants (such as uranium) that hydrolyze in alkaline media that form precipitant phases and tend to deposit at the near-surface. However, more soluble contaminants, such as Cs-137 (as Cs{sup +}) and Tc-99 (as the pertechnetate anion TcO{sub 4}{sup -}) diffuse more rapidly (and deeply) into the porous substrate. Profiling the migration of the water-soluble radionuclides into a cure (hardened) cement surface is a challenge, since water-cooled saws, borers and similar implements are often used to excise and/or slice the core. Alternately, dry mechanical fracturing for excavation of cement may introduce the possibility of material cross-contamination and uncertainty for the average sampling depth for the sample collection event, potentially yielding non-representative samples, and may preclude determination of crack formation that may have been present in the native (non-fractured) substrate. Structural concrete is comprised of cement and pozzolan paste, relatively impervious aggregate (typically stone and/or sand), and rebar (iron reinforcement). Near-surface aggregate may act as a hydrolytic barrier, causing contaminants leached into the pore water to by-pass the impervious grains, causing deeper-than expected penetration, especially if there are grain boundary cracks also present to facilitate migration. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2019

Developing Waste Characterization Capabilities in Support of the Near Surface Disposal Facility - 19245

Upon approval from the Canadian Nuclear Safety Commission, Canadian Nuclear Laboratories (CNL) Proposed Near Surface Disposal Facility (NSDF) to be constructed at CNL's Chalk River Laboratories will be the first permanent disposal facility in Canada for the disposal of low level radioactive waste. The NSDF is currently in the approval process and as such, a preliminary Waste Acceptance Criteria (WAC) has been implemented for the proposed facility. Waste currently generated at CNL is being characterized to verify that it meets the WAC and will be 'disposal ready' once the NSDF is operational. A robust waste characterization program is required for the following reasons: 1. Improved waste segregation to support waste minimization and recycling to ensure non-radioactive waste is reliably segregated and removed from radioactive waste streams destined for the NSDF. This includes characterization and discrimination of Naturally Occurring Radioactive Material (NORM) and anthropogenic radioactive material. 2. To ensure low level waste (LLW) is properly characterized as per the limits stipulated within the WAC to ensure criteria is met for NSDF packaging requirements 3. To ensure intermediate level waste is reliably segregated from NSDF destined wastes streams The purpose of this paper is to provide a review of the development of a waste characterization program strategy at Chalk River Laboratories and applicability of various waste streams; including consideration of important factors such as measurement methods, techniques, and the management of data. Emphasis is necessarily placed on non-destructive gamma spectrometry systems which are central to CNL's approach. A review of near-term developments is also provided. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2014

A Low-Tech, Low-Budget Storage Solution for High Level Radioactive Sources

The need for safe, secure, and economical storage of radioactive material becomes increasingly important as beneficial uses of radioactive material expand (increases inventory), as political instability rises (increases threat), and as final disposal and treatment facilities are delayed (increases inventory and storage duration). Several vendor-produced storage casks are available for this purpose but are often costly — due to the required design, analyses, and licensing costs. Thus the relatively high costs of currently accepted storage solutions may inhibit substantial improvements in safety and security that might otherwise be achieved. This is particularly true in areas of the world where the economic and/or the regulatory infrastructure may not provide the means and/or the justification for such an expense. This paper considers a relatively low-cost, low-technology radioactive material storage solution. The basic concept consists of a simple shielded storage container that can be fabricated locally using a steel pipe and a corrugated steel culvert as forms enclosing a concrete annulus. Benefits of such a system include 1) a low-tech solution that utilizes materials and skills available virtually anywhere in the world, 2) a readily scalable design that easily adapts to specific needs such as the geometry and radioactivity of the source term material), 3) flexible placement allows for free-standing above-ground or in-ground (i.e., below grade or bermed) installation, 4) the ability for future relocation without direct handling of sources, and 5) a long operational lifetime . ‘Le mieux est l’ennemi du bien’ (translated: The best is the enemy of good) applies to the management of radioactive materials – particularly where the economic and/or regulatory justification for additional investment is lacking. Development of a low-cost alternative that considerably enhances safety and security may lead to a greater overall risk reduction than insisting on solutions that remain economically and/or politically ‘out of reach’.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2021

Gamma Spectroscopy Detector Candidates and Radioisotope Identification Algorithms for Use in National Security Applications

In 2006, the United States Congress mandated for the Department of Homeland Security (DHS) to screen all cargo containers to protect against terrorist acts and ensure the safety and security of the nation. Containers are screened by gamma and neutron detectors to ensure threat material is not smuggled into the country. However, because commerce is radioactive, detecting the presence of radioactive materials is not sufficient in ensuring the safety and security of the nation. Radioactive materials must also be identified in real time, thus distinguishing threat sources (Uranium-235 and Plutonium-230) from non-threat sources (kitty litter, pot ash, medical isotopes). Screening cargo containers can be considered a two-step process (1) alerting to the presence of radioactive material when gamma counts exceed a threshold setting, and (2) once alerted, identifying the type of radioactive material, which is done by collecting a gamma spectra and analyzing it with an analysis tool/algorithm. For this reason, it is important to evaluate not only emerging technology in neutron and gamma detection, but also investigate new advances in algorithm development for radioisotope identification (RIID). New candidates in detection and on-board algorithm analysis might offer opportunities to make the scanning, detection, and identification process more efficient while still ensuring the health and safety of the public. This research will investigate emerging technology in radiation detection focused on gamma spectroscopy capabilities and RIID algorithms for DHS applications.

61 RADIATION PROTECTION AND DOSIMETRY↗

DOE OSTI2016

SU-F-P-24: Radiological Disperse Device

Purpose: We are now living in a society of constant fear of terrorism. This topic is pertaining to give a general knowledge of what is a radiological dispersion device or RDD and in case of its detonation, what are the options open to public for a safe action in terms of reducing the exposure and knowing the proper steps. These RDD are also called dirty bombs. Methods: Compared to nuclear weapons, dirty bombs are easy to make. In order for a terrorist organization to construct and detonate a dirty bomb, it must acquire radioactive material by stealing it or buying it through legal or illegal channels. Possible RDD material could come from the millions of radioactive sources used in the industry, for medical purposes and in academic applications mainly for researches. These are, americium-{sup 241}, californium-{sup 252}, caesium-{sup 137}, cobalt-{sup 60}, iridium-{sup 192}, plutonium-{sup 238}, polonium-{sup 210}, radium-{sup 226} and strontium-{sup 90}. Results: Prompt detection of the type of radioactive material used will greatly assist advising people on the protective measures, like sheltering in place, or quickly leaving the immediate area. The effects of radiation are determined by:°the amount of radiation absorbed by body°the type of radiation °the distance from the radiation to an individual°the means of exposure absorbed by the skin, inhaled, or ingested; and length of time exposed. Conclusion: In any facility it is now much more important to keep a log list of all radioactive materials in use. In case there is a dirty bomb explosion, the chaos and economic cost could be enormous. The economic cost for the evaluation of the contamination, survey of people and surroundings and the after treatment, decontamination cost and effort will be a big challenge in any country. So awareness and preparation is the start to face this new type of challenge.

61 RADIATION PROTECTION AND DOSIMETRY↗

DOE OSTI2021

Radiation Dispersal Devices. A brief overview [Slides]

In this presentation I lump together the "classified RDD" - a dispersion of aerosolized radioactive material - with the nefarious use of radioactive materials. This can include other means of dispersal as well as an RED - a Radiological Exposure Device. This combination is because the threat is the nefarious use of radioactive material, and most of our concerns are in regards to the loss of control of the material, potential(s) for misuse, and detection.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗

DOE OSTI2019

Designing Flexibility into the Authorized Radioactive Contents of the 9982 Shipping Package

The 9982 radioactive material package is being designed to safely transport small gram quantities of radioactive material within the United States. Typically, such shipping packages are designed to ship only a single radioactive material content within the U.S., which greatly limits the type of radioactive material allowed for shipment. The 9982’s content, however, is designed around bounding limits for numerous radionuclides, which will allow many more content variations to be shipped in a single package compared to other package designs. Here, contents from 3013, 9977, and 9978 packages are analyzed to determine if they are qualified for shipment in the 9982 using a sum-of-the-fractions methodology to see if the sum of the ratios of the masses of the radionuclides over the mass limits exceeds a value of one (1). Since all three of the example contents meet satisfy this method, the maximum content that could be shipped in a 9982 was determined. For the 3013 package, up to between 199.96 grams and 200 grams of a plutonium mixture could be shipped depending on the weight percentages of the isotopes. The 9977 material resulted in a 174-gram content that satisfies the summations for either metal or oxide form and regardless of whether a shielding pig is present or not. Lastly, the 9978 materials, two different americium standards, have a maximum content mass of 200 grams regardless of whether the americium-241 and americium-243 are shipped together or separately. These three applications of the 9982 exemplify the use for a package with multiple approved contents since the functions of three separate packages are fulfilled by one new package, reducing the need for separate operational procedures.

36 MATERIALS SCIENCE↗

DOE OSTI2013

Intrinsic Dosimetry: Elemental Composition Effects on the Thermoluminescence of Commercial Borosilicate Glass

Intrinsic dosimetry is the method of measuring total absorbed dose received by the walls of a container holding radioactive material. By considering this dose in tandem with the physical characteristics of the radioactive material housed within the container, this method can provide enhanced pathway information for interdicted radioactive samples. Thermoluminescence (TL) dosimetry was used to measure ionizing radiation dose effects on stock borosilicate glass. Differences in TL glow curve shape and intensity were observed for glasses from different geographical origins. The different TL signatures strongly correlated with the concentration of alkaline earth metals and the ratio of sodium to the total amount of alkali metal present in the borosilicate glass.

61 RADIATION PROTECTION AND DOSIMETRY↗

DOE OSTI2020

In situ liquid SIMS analysis of uranium oxide

Trace analysis of nuclear materials in solid particles collected in the environment or particles in liquid slurry generated in nuclear material manufacturing processes can pinpoint elemental, organic, and isotopic signatures of nuclear fuel cycle activities and processes. Such information can support nuclear safeguards programs by increasing our ability to detect undeclared nuclear materials, routine activities for safeguarding at declared facilities, and illicit activities. However, trace radioactive material analysis in liquids and slurries is challenging using bulk approaches. For example, one drawback of sensitive analysis such as inductively coupled plasma mass spectrometry (ICP-MS) is that sample is consumed or destroyed as a result of the technical approach. We developed a vacuum compatible microfluidic interface to enable surface analysis of liquids and liquid-solid interactions using time-of-flight secondary ion mass spectrometry (ToF-SIMS). In this work, we illustrate initial results of liquid standards containing uranium using in situ liquid SIMS. Specifically a series of diluted uranium standards used for ICPMS analysis were studied and the limit of detection was estimated. Since the liquid SIMS analysis is almost nondestructive, the same sample can be analyzed by other more destructive approaches afterwards or saved for future references. Consequently, multimodal analysis is possible. Our results demonstrate that in situ liquid SIMS can be used as a new approach to analyze radioactive materials in liquid and slurry forms of relevance to the IAEA safeguards missions.

In situ liquid ToF-SIMS, uranium, limit of detecti↗

DOE OSTI2017

Risks of Hazardous Substances in Radioactive Waste for the Konrad Repository in Germany - 17522

When disposing of radioactive waste with negligible heat generation, the activity of the radionuclides is limited. However, the waste including radioactive material comprises a certain proportion of non-radioactive material. The risk of hazardous contamination of the groundwater by non-radioactive substances must be taken into account. It must be ascertained that the non-radioactive material cannot affect near-surface groundwater, which is a resource for drinking water supply. To achieve this, limit values on the amount of hazardous substances in the total waste volume shall be determined. In 2002 a regulatory approval was granted to the 'Konrad' final storage facility for radioactive waste with negligible heat generation according to the German Water Resources Act. This approval is embedded in the license (plan-approval decision) based on the German Atomic Energy Act. The approval is based on the model of a possible discharge of contaminants from the final storage facility. In a long-term simulation spanning 300,000 years, contact of the waste with the groundwater in the surrounding rock formations over the postoperational phase was conservatively assumed. The maximum amount of allowable disposal of substances - such that no concern of affecting the near-surface groundwater arises - can be derived from the solubility of the respective substances. Implementing the permit according to the Water Resources Act requires: - classification of the waste through delivery declaration obligations - monitoring the substance inspection in the waste to assess its suitability for the disposal, and - stock keeping procedures for the disposal waste by the operator. While the repository is operated by the Federal Office for Radiation Protection (BfS) (http://www.bfs.de./EN/home/home{sub n}ode;), reporting to the Federal Environment Ministry, the statutory water permit is issued and applied by the State of Lower Saxony as responsible state authority. A waste package/container list supplements a comprehensive list of substances. From this - depending on the respectively conditioned waste - material vectors can be derived. For this purpose, BfS provides a database with a substances and container list to the waste owners. In the meantime, first experiences have been collected in applying the approval. More than 540 waste containers with a total mass of almost 6,000 Mg have been controlled and are ready for disposal. In our presentation we will show the recent development in supervising the preparation for the disposal of mixed waste. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2016

An Aerial Survey of the 200 East and 200 West Areas of the Hanford Nuclear Reservation - October 2016

The U.S. Department of Energy (DOE) National Nuclear Security Administration (NNSA) Aerial Measuring System (AMS), based at the Remote Sensing Laboratory (RSL) in Las Vegas, Nevada, performed an aerial survey of the 200 West and 200 East Areas of the DOE Hanford Site during September 2015. The survey was performed using the RSL Bell 412 helicopter equipped with twelve 2"x4"x16" thallium-activated sodium iodide (NaI) logs with their spectra summed to form a single detector and a mechanically-cooled high-purity germanium (HPGe) detector. Both detectors collected gamma ray spectra from naturally-occurring radioactive materials and from anthropogenic radioactive materials present due to activities at the site. Data was collected over the site during the 30 hours of survey flight time, resulting in approximately 100,000 one-second spectra collected by both the NaI array and the HPGe detector. These data have been analyzed to map the distribution of anthropogenic radioactivity and identify the isotopes responsible for that activity.

200 East↗

DOE OSTI2022

A microfluidic electrochemical cell for studying the corrosion of uranium dioxide (UO 2 )

We have developed a specialized microfluidic electrochemical cell that enables in situ investigation of the electrochemical corrosion of microgram quantities of redox active solids. The advantage of downscaling is the reduction of hazards, waste, expense, and greatly expanding data collection for hazardous materials, including radioactive samples. Cyclic voltammetry was used to monitor the oxidation–reduction cycle of minute quantities of micron-size uraninite (UO 2 ) particles, from the formation of hexavalent uranium (U(VI)), U 3 O 7 and reduction to UO 2+x . Reaction progress was also studied in situ with scanning electron microscopy. The electrochemical measurements matched those obtained at the bulk-scale and were consistent with ex situ characterization of the run products by X-ray photoelectron spectroscopy, scanning transmission electron microscopy, and atomic force microscopy; thus, demonstrating the utility of the microfluidic approach for studying radioactive materials.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗

DOE OSTI2025

Quartz Ampoule Loading, Sealing, and Inspection

This procedure applies to the loading of materials into quartz ampoules and flame sealing these ampoules. Flame sealed quartz ampoules are commonly used as a sealed containment for neutron irradiation. Due to the importance of maintaining containment for this application, this procedure involves a double encapsulation design wherein a sealed inner ampoule is sealed is in turn sealed within a larger diameter outer ampoule. General guidance for inspection of ampoules by destructive, non-destructive, qualitative (e.g., visual) and other methods are given. Materials to be placed inside the ampoules may consist of stable element materials or radioactive materials in either solid or liquid form. Liquids shall be dried prior to sealing the ampoule.

36 MATERIALS SCIENCE↗

DOE OSTI2014

Effect of atmospheric conditions on operation of terahertz systems for remote detection of ionizing materials

This study was motivated by a new concept of remote detection of concealed radioactive materials by using a high power terahertz (THz) wave beam, which can be focused in a small spot where the wave electric field exceeds the breakdown threshold. In the presence of seed electrons in such a volume, this focusing can initiate the avalanche breakdown. Typically, an ambient density of free electrons is assumed to be at the level of one particle per cubic centimeter. So, when a breakdown-prone volume is smaller than 1 cm{sup 3}, there should be significant difference between the breakdown rates in the case of presence of additional sources of ionization versus its absence. Since the flux density of gamma rays emitted by radioactive materials rapidly falls with the distance from the source, while the intensity of THz waves also decreases with the distance due to wave attenuation in the atmosphere, it is important to find an optimal location of the breakdown to be initiated for a given distance between a radioactive material and a THz antenna. This problem is analyzed in a given paper with the account for not only atmospheric attenuation of THz waves but also the air turbulence.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

DOE OSTI2016

Nondestructive Analysis of MET-5 Paint Can at TA35 Building 2 A-Wing Vault

In Building 2 A-wing vault MET-5 has some drums and other packages they wanted NEN-1 help identifying nondestructively. Measurements using a mechanically cooled portable high-purity germanium HPGe Ortec detective were taken of a paint can container labeled DU-2A to determine if any radioactive material was inside. The HPGe detector measures the gamma rays emitted by radioactive material and displays it as a spectrum. The spectrum is used to identify this radioactive material by using appropriate analysis software and identifying the gamma ray peaks. A paint can container, DU-2A, was analyzed with PeakEasy 4.84 and FRAM 5.2. The FRAM report is shown. The enrichment is 0.091% U235 and 99.907% U238. This material is depleted uranium. The measurement was performed in the near field, and to extract a mass a far field measurement will need to be taken.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2015

Safety Analysis Report for Packaging, Y-12 National Security Complex, Model ES-3100 Package with Bulk HEU Contents

This safety analysis report for packaging (SARP) presents the results of the safety analysis prepared in support of the Consolidated Nuclear Security, LLC (CNS) request for licensing of the Model ES-3100 package with bulk highly enriched uranium (HEU) contents and issuance of a Type B(U) Fissile Material Certificate of Compliance. This SARP, published in the format specified in the Nuclear Regulatory Commission (NRC) Regulatory Guide 7.9 and using information provided in UCID-21218 and NRC Regulatory Guide 7.10, demonstrates that the Y-12 National Security Complex (Y-12) ES-3100 package with bulk HEU contents meets the established NRC regulations for packaging, preparation for shipment, and transportation of radioactive materials given in Title 10, Part 71, of the Code of Federal Regulations (CFR) [10 CFR 71] as well as U.S. Department of Transportation (DOT) regulations for packaging and shipment of hazardous materials given in Title 49 CFR. To protect the health and safety of the public, shipments of radioactive materials are made in packaging that is designed, fabricated, assembled, tested, procured, used, maintained, and repaired in accordance with the provisions cited above. Safety requirements addressed by the regulations that must be met when transporting radioactive materials are containment of radioactive materials, radiation shielding, and assurance of nuclear subcriticality.

42 ENGINEERING↗

DOE OSTI2017

Examining the Effect of Plume Rise on Radiological Consequences of Nuclear Accidents

A nuclear accident could cause release of radioactive material outside containment. This material will eventually disperse into the surrounding environment, and could pose a serious threat to public safety, and environment. Mitigation of radiological consequences of such an accident is highly desirable, and since Fukushima accident, there has been a growing focus on nuclear utilities to develop capabilities for this purpose. Undoubtedly, suppression of radioactive material release and dispersion is the primary mean for mitigating radiological consequences nevertheless alternative methods should also be explored to broaden the spectrum of choices for actual circumstances. As we know that, dispersion of radioactive material and subsequent radiological consequences are affected by plume rise. Plume rise is an important factor in determining ground level contamination since it can increase effective release height appreciably provided that effluent discharge speed and temperature is high enough. Under most circumstances, one can expect reduction in radiological consequences due to lower levels of radiation dose and ground contamination in the presence of adequate plume rise. Nevertheless, the effect of plume rise is usually ignored in radiological consequence studies for the sake of conservatism, and lack of information. However, this particular attribute of plume rise interested us to investigate the effect of plume rise in the scope of consequence mitigation and how this advantage could be utilized during an accident progression to minimize the impact of radioactivity release to the environment. In this work, we examine the effect of plume rise on radiological consequences of a nuclear accident for plume rise contributions much larger ({approx}500 m) than usually achievable in normal circumstances. The effect of plume rise on radiological consequences is quantified in this study as decontamination credit (DCC) achievable corresponding to maximum annual dose. This analysis is performed for a number of release heights and atmospheric conditions. We discuss available results in the scope of radiological consequence mitigation, devising a strategy for utilizing plume rise phenomenon with the help of an external propelling device like a jet engine for radiological consequence management. This study is continuation of our efforts for devising systems and strategies to mitigate consequences of radioactivity release accidents like Fukushima. We have proposed several ideas for suppressing/preventing the dispersion of released radioactive material to the environment using offsite equipment.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗