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At least 271 records · Page 15

Smart Planning for Radioactive Source Transport Advanced Tools for Increased Safety and Efficiency

End-of-life (EOL) management of high-activity radioactive sources is made uniquely challenging by the inherent risks associated with storage and transportation of these sources, the complex logistics involved, and the strict requirements for regulatory compliance. Traditional methods lack comprehensive tools for accurate site assessments and precision planning for the transportation of radioactive sources. They also frequently fail to provide the adaptability required to consider diverse operational environments, resulting in inefficiencies and potential safety concerns. This paper introduces a novel software solution developed to address these issues by integrating advanced technologies such as light detection and ranging (LiDAR)-based 3D environment modeling, smart dynamic route planning, and customizable measurement functionalities. This software enables detailed terrain visualizations, facilitating thorough environmental assessments and enabling users to virtually navigate, analyze, and plan site-specific operations. Among the key features are a user-centric interface for virtual navigation, precise site measurement tools for site evaluations, interactive visualizations that highlight potential operational hazards, dynamic route planning capabilities, and real-time collision detection to promote safe workflows. By demonstrating the effectiveness of this tool through real-world application, the present work underscores the tool’s potential to revolutionize radioactive source EOL management by improving operational efficiencies, minimizing risk, and advancing the state of practice to achieve suitable and secure radioactive material handling.

99 - GENERAL AND MISCELLANEOUS↗

AI-assisted transport of radioactive ion beams

Beams of radioactive heavy ions allow researchers to study rare and unstable atomic nuclei, shedding light into the internal structure of exotic nuclei and on how chemical elements are formed in stars. However, the extraction and transport of radioactive beams rely on time-consuming expert-driven tuning methods, where hundreds of parameters are manually optimized. Here, in this study, we introduce a system that employs Artificial Intelligence (AI), specifically utilizing Bayesian Optimization, to assist in the transport process of radioactive beams. We apply our methodology to real-life scenarios showing advantages when compared with standard tuning methods. This AI-assisted approach can be extended to other radioactive beam facilities around the world to improve operational efficiency and enhance scientific output.

43 PARTICLE ACCELERATORS↗

SU-G-201-16: Thermal Imaging in Source Visualization and Radioactivity Measurement for High Dose Rate Brachytherapy

Purpose: High Dose Rate (HDR) brachytherapy poses a special challenge to radiation safety and quality assurance (QA) due to its high radioactivity, and it is thus critical to verify the HDR source location and its radioactive strength. This study demonstrates a new method for measuring HDR source location and radioactivity utilizing thermal imaging. A potential application would relate to HDR QA and safety improvement. Methods: Heating effects by an HDR source were studied using Finite Element Analysis (FEA). Thermal cameras were used to visualize an HDR source inside a plastic applicator made of polyvinylidene difluoride (PVDF). Using different source dwell times, correlations between the HDR source strength and heating effects were studied, thus establishing potential daily QA criteria using thermal imaging Results: For an Ir1?2 source with a radioactivity of 10 Ci, the decay-induced heating power inside the source is ∼13.3 mW. After the HDR source was extended into the PVDF applicator and reached thermal equilibrium, thermal imaging visualized the temperature gradient of 10 K/cm along the PVDF applicator surface, which agreed with FEA modeling. For Ir{sup 192} source activities ranging from 4.20–10.20 Ci, thermal imaging could verify source activity with an accuracy of 6.3% with a dwell time of 10 sec, and an accuracy of 2.5 % with 100 sec. Conclusion: Thermal imaging is a feasible tool to visualize HDR source dwell positions and verify source integrity. Patient safety and treatment quality will be improved by integrating thermal measurements into HDR QA procedures.

60 APPLIED LIFE SCIENCES↗

The Model 9977 Radioactive Material Packaging Primer

The Model 9977 Packaging is a single containment drum style radioactive material (RAM) shipping container designed, tested and analyzed to meet the performance requirements of Title 10 the Code of Federal Regulations Part 71. A radioactive material shipping package, in combination with its contents, must perform three functions (please note that the performance criteria specified in the Code of Federal Regulations have alternate limits for normal operations and after accident conditions): Containment, the package must “contain” the radioactive material within it; Shielding, the packaging must limit its users and the public to radiation doses within specified limits; and Subcriticality, the package must maintain its radioactive material as subcritical

42 ENGINEERING↗

Concepts for Environmental Radioactive Air Sampling and Monitoring

Environmental radioactive air sampling and monitoring is becoming increasingly important as regulatory agencies promulgate requirements for the measurement and quantification of radioactive contaminants. While researchers add to the growing body of knowledge in this area, events such as earthquakes and tsunamis demonstrate how nuclear systems can be compromised. The result is the need for adequate environmental monitoring to assure the public of their safety and to assist emergency workers in their response. Two forms of radioactive air monitoring include direct effluent measurements and environmental surveillance. This chapter presents basic concepts for direct effluent sampling and environmental surveillance of radioactive air emissions, including information on establishing the basis for sampling and/or monitoring, criteria for sampling media and sample analysis, reporting and compliance, and continual improvement.

emissions↗

Analytics of Radioactive Materials Released in the Fukushima Daiichi Nuclear Accident

The 2011 Fukushima Daiichi nuclear accident in Japan resulted in the release of radioactive materials into the atmosphere, the nearby sea, and the surrounding land. Following the accident, several meteorological models were used to predict the transport of the radioactive materials to other continents such as North America and Europe. Also of high importance is the dispersion of radioactive materials locally and within Japan. Based on the International Atomic Energy Agency (IAEA) Convention on Early Notification of a nuclear accident, several radiological data sets were collected on the accident by the Japanese authorities. Among the radioactive materials monitored, are I-131 and Cs-137 which form the major contributions to the contamination of drinking water. The radiation dose in the atmosphere was also measured. It is impractical to measure contamination and radiation dose in every place of interest. Therefore, modeling helps to predict contamination and radiation dose. Some modeling studies that have been reported in the literature include the simulation of transport and deposition of I-131 and Cs-137 from the accident, Cs-137 deposition and contamination of Japanese soils, and preliminary estimates of I-131 and Cs-137 discharged from the plant into the atmosphere. In this paper, we present statistical analytics of I-131 and Cs-137 with the goal of predicting gamma dose from the Fukushima Daiichi nuclear accident. The data sets used in our study were collected from the IAEA Fukushima Monitoring Database. As part of this study, we investigated several regression models to find the best algorithm for modeling the gamma dose. The modeling techniques used in our study include linear regression, principal component regression (PCR), partial least square (PLS) regression, and ridge regression. Our preliminary results on the first set of data showed that the linear regression model with one variable was the best with a root mean square error of 0.0133 μSv/h, compared to 0.0210 μSv/h for PCR, 0.231 μSv/h for ridge regression L-curve, 0.0856 μSv/h for PLS, and 0.0860 μSv/h for ridge regression cross validation. Complete results using the full datasets for these models will also be presented. (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Dose Calculation For Accidental Release Of Radioactive Cloud Passing Over Jeddah

For the evaluation of doses after the reactor accident, in particular for the inhalation dose, a thorough knowledge of the concentration of the various radionuclide in air during the passage of the plume is required. In this paper we present an application of the Gaussian Plume Model (GPM) to calculate the atmospheric dispersion and airborne radionuclide concentration resulting from radioactive cloud over the city of Jeddah (KSA). The radioactive cloud is assumed to be emitted from a reactor of 10 MW power in postulated accidental release. Committed effective doses (CEDs) to the public at different distance from the source to the receptor are calculated. The calculations were based on meteorological condition and data of the Jeddah site. These data are: pasquill atmospheric stability is the class B and the wind speed is 2.4m/s at 10m height in the N direction. The residence time of some radionuclides considered in this study were calculated. The results indicate that, the values of doses first increase with distance, reach a maximum value and then gradually decrease. The total dose received by human is estimated by using the estimated values of residence time of each radioactive pollutant at different distances.

61 RADIATION PROTECTION AND DOSIMETRY↗

Solidification of radioactive waste resins using cement mixed with organic material

Solidification of radioactive waste resins using cement mixed with organic material i.e. biochar is described in this paper. Different percentage of biochar (0%, 5%, 8%, 11%, 14% and 18%) was investigated in this study. The characteristics such as compressive strength and leaching behavior were examined in order to evaluate the performance of solidified radioactive waste resins. The results showed that the amount of biochar affect the compressive strength of the solidified resins. Based on the data obtained for the leaching experiments performed, only one formulation showed the leached of Cs-134 from the solidified radioactive waste resins.

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Intrinsic Efficiency Calibration Considering Geometric Factors in Gamma-ray Computed Tomography for Radioactive Waste Assay

In radioactive waste assay with gamma-ray computed tomography, calibration for intrinsic efficiency of the system is important to the reconstruction of radioactivity distribution. Due to the geometric characteristics of the system, the non-uniformity of intrinsic efficiency for gamma-rays with different incident positions and directions are often un-negligible. Intrinsic efficiency curves versus geometric parameters of incident gamma-ray are obtained by Monte-Carlo simulation, and two intrinsic efficiency models are suggested to characterize the intrinsic efficiency determined by relative source-detector position and system geometry in the system matrix. Monte-Carlo simulation is performed to compare the different intrinsic efficiency models. Better reconstruction results of radioactivity distribution are achieved by both suggested models than by the uniform intrinsic efficiency model. And compared to model based on detector position, model based on point response increases reconstruction accuracy as well as complexity and time of calculation. (authors)

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An overview of the draft for the amendment of 'nuclear materials and radioactive waste management act'

The 'Nuclear Materials and Radioactive Waste Management Act' (NMRWMA) in Taiwan has been in use since 2002. To promote further administrative efficiency and improve regulatory capacity, an amendment of the act has been initiated by the Atomic Energy Council (AEC). It is now being reviewed by outside experts and related communities so as to include the best understanding of risk management factors. For the future decommissioning challenges of nuclear facilities, the act is also being amended to comply with the regulatory requirements of the decommissioning mandates. Currently the Taiwan government is conducting government reorganization, and AEC will be reformed but will remain as an independent regulatory body. AEC will then be capable of improving the regulatory capacity for facilitating licensing and inspection, ensuring operational safety, environmental protection and public involvement, and giving a more flexible administrative discretion, such as expending the margin of penalty. The amendment is also required to provide a formal legal basis for the Nuclear Backend Fund, and to mandate the waste producers to take responsibility for any final debt repayment. In addition, this amendment promotes measures to prevent accidents or emergencies concerning radioactive materials and facilities and procedures to reduce the impact and effect of any unexpected events. Furthermore, this amendment intends to implement the concept of information transparency and public participation so as to meet the public needs. Finally, radioactive waste final disposal tasks have to be completed by waste producers under the supervision of the AEC. (authors)

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Radioactive waste management: the relation between geological disposal and advanced nuclear technologies

Throughout this paper we aim to scope the most pregnant themes, issues and research questions concerning the relation between geological disposal and advanced nuclear technologies in the broad context of radioactive waste management. Especially from a socio-technical point of view the mutual impacts, divergences and complementarities between both strategies seem to have received limited dedicated examination up until today. Specific attention is paid to the main arguments that seem to underpin both research streams, related to how the issue of radioactive waste is contextualized and which problems and solutions are consequently identified and proposed. Ultimately we aim to encourage scientifically integer communication and constructive dialogue between both fields, to investigate the common possibilities of enhancing radioactive waste management as a whole. (authors)

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Social scientist on board in long-term management of high level and/or long-lived radioactive waste in Belgium

In Belgium, the long-term management of radioactive waste is under the exclusive competence of the Belgian Agency for Radioactive Waste and Enriched Fissile Materials (knew as ONDRAF/NIRAS). Unlike low-level waste, no institutional policy has yet been formally approved for the long-term management of high level and/or long-lived radioactive waste (knew as B and C waste). In this context, ONDRAF/NIRAS considers the public and stakeholders' participation as an essential factor in the formulation of an effective and legitimate policy. This is why it has decided to integrate them in different ways during the elaboration of the Waste Plan (ONDRAF/NIRAS-document containing guidelines to make a principled policy decision about nuclear waste management). To do so, social scientists have been regularly mobilized either as external evaluators, follow-up committee members, or participatory observants. Hence, the Waste Plan is only the first step in a long decision-making process. For a PhD student under contract with ONDRAF/NIRAS, this mandate consists of thinking out a way to construct an inter-organizational innovative communication system that would be participative, transparent and embedded in a long-term perspective, thus integrating all the further legal steps to take throughout the decision-making process. In this regard, two paradoxical constraints must be taken into account: on the one hand, my own influence on the legal decision-making process should remain limited, because of a series of constraints, lock-ins and previous decisions which have to be respected; on the other hand, ONDRAF/NIRAS expects the research conclusions to be policy relevant and useful. In this paper, the purpose is twofold. Firstly, the issues raised by this policy mandate is an opportunity to question the per-formative dimensions of the social scientist in the decision-making process and, more specifically, to have a reflexive view on our position as PhD Student. Secondly, assuming the role of 'embarked' social scientist, numerous of answers will discuss to face the different dilemmas of the researcher 'in action'. Those reflections follow on, among others, those from previous papers discussed in Quimper in April 2013 and in Leuven in June 2013. (authors)

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Reference design and operations for deep borehole disposal of high-level radioactive waste.

A reference design and operational procedures for the disposal of high-level radioactive waste in deep boreholes have been developed and documented. The design and operations are feasible with currently available technology and meet existing safety and anticipated regulatory requirements. Objectives of the reference design include providing a baseline for more detailed technical analyses of system performance and serving as a basis for comparing design alternatives. Numerous factors suggest that deep borehole disposal of high-level radioactive waste is inherently safe. Several lines of evidence indicate that groundwater at depths of several kilometers in continental crystalline basement rocks has long residence times and low velocity. High salinity fluids have limited potential for vertical flow because of density stratification and prevent colloidal transport of radionuclides. Geochemically reducing conditions in the deep subsurface limit the solubility and enhance the retardation of key radionuclides. A non-technical advantage that the deep borehole concept may offer over a repository concept is that of facilitating incremental construction and loading at multiple perhaps regional locations. The disposal borehole would be drilled to a depth of 5,000 m using a telescoping design and would be logged and tested prior to waste emplacement. Waste canisters would be constructed of carbon steel, sealed by welds, and connected into canister strings with high-strength connections. Waste canister strings of about 200 m length would be emplaced in the lower 2,000 m of the fully cased borehole and be separated by bridge and cement plugs. Sealing of the upper part of the borehole would be done with a series of compacted bentonite seals, cement plugs, cement seals, cement plus crushed rock backfill, and bridge plugs. Elements of the reference design meet technical requirements defined in the study. Testing and operational safety assurance requirements are also defined. Overall, the results of the reference design development and the cost analysis support the technical feasibility of the deep borehole disposal concept for high-level radioactive waste.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Radioactive waste management treatments: A selection for the Italian scenario

The increased attention for radioactive waste management is one of the most peculiar aspects of the nuclear sector considering both reactors and not power sources. The aim of this paper is to present the state-of-art of treatments for radioactive waste management all over the world in order to derive guidelines for the radioactive waste management in the Italian scenario. Starting with an overview on the international situation, it analyses the different sources, amounts, treatments, social and economic impacts looking at countries with different industrial backgrounds, energetic policies, geography and population. It lists all these treatments and selects the most reasonable according to technical, economic and social criteria. In particular, a double scenario is discussed (to be considered in case of few quantities of nuclear waste): the use of regional, centralized, off site processing facilities, which accept waste from many nuclear plants, and the use of mobile systems, which can be transported among multiple nuclear sites for processing campaigns. At the end the treatments suitable for the Italian scenario are presented providing simplified work-flows and guidelines. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Determination of Iodine-129 in Low Level Radioactive Wastes - 13334

For the radioactivity determination of {sup 129}I in the radioactive wastes, alkali fusion and anion-exchange resin separation methods, which are sample pretreatment methods, have been investigated in this study. To separate and quantify the {sup 129}I radionuclide in an evaporator bottom and spent resin, the radionuclide was chemically leached from the wastes and adsorbed on an anion exchange resin at pH 4, 7, 9. In the case of dry active waste and another solid type, the alkali fusion method was applied. KNO{sub 3} was added as a KOH and oxidizer to the wastes. It was then fused at 450 deg. C for 1 hour. The radioactivity of the separated iodine was measured with a low energy gamma spectrometer after the sample pretreatment. Finally, it was confirmed that the recovery rate of the iodine for the alkali fusion method was 83.6±3.8%, and 86.4±1.6% for the anionic exchange separation method. (authors)

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Assessment of Quality Assurance Measures for Radioactive Material Transport Packages not Requiring Competent Authority Design Approval - 13282

The majority of transports of radioactive materials are carried out in packages which don't need a package design approval by a competent authority. Low-active radioactive materials are transported in such packages e.g. in the medical and pharmaceutical industry and in the nuclear industry as well. Decommissioning of NPP's leads to a strong demand for packages to transport low and middle active radioactive waste. According to IAEA regulations the 'non-competent authority approved package types' are the Excepted Packages and the Industrial Packages of Type IP-1, IP-2 and IP-3 and packages of Type A. For these types of packages an assessment by the competent authority is required for the quality assurance measures for the design, manufacture, testing, documentation, use, maintenance and inspection (IAEA SSR 6, Chap. 306). In general a compliance audit of the manufacturer of the packaging is required during this assessment procedure. Their regulatory level in the IAEA regulations is not comparable with the 'regulatory density' for packages requiring competent authority package design approval. Practices in different countries lead to different approaches within the assessment of the quality assurance measures in the management system as well as in the quality assurance program of a special package design. To use the package or packaging in a safe manner and in compliance with the regulations a management system for each phase of the life of the package or packaging is necessary. The relevant IAEA-SSR6 chap. 801 requires documentary verification by the consignor concerning package compliance with the requirements. (authors)

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The Low-Level Radioactive Waste Management Office: Thirty Years of Experience in Canada - 13308

This paper reviews thirty years of progress by the Low-Level Radioactive Waste Management Office (LLRWMO) in developing and implementing low-level radioactive waste (LLRW) remediation projects and environmentally safe co-existence strategies. It reports on the present status and the future of the national historic waste program in Canada. There are over two million cubic metres of historic LLRW in Canada. Historic LLRW is broadly defined as LLRW that was managed in the past in a manner that is no longer considered acceptable and for which the original owner cannot reasonably be held accountable. In many cases, the original owner can not be identified or no longer exists. The LLRWMO was established in 1982 as Canada's agent to carry out the responsibilities of the federal government for the management of historic LLRW. The LLRWMO is operated by Atomic Energy of Canada Limited (AECL) through a cost-recovery agreement with Natural Resources Canada (NRCan), the federal department that provides the funding and establishes national policy for radioactive waste management in Canada. The LLRWMO expertise includes project managers, environmental remediation specialists, radiation surveyors, communications staff and administrative support staff. The LLRWMO in providing all aspects of project oversight and implementation contracts additional resources supplementing core staff capacity as project/program demands require. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Removal of Historic Low-Level Radioactive Sediment from the Port Hope Harbour - 13314

At the Port Hope Harbour, located on the north shore of Lake Ontario, the presence of low-level radioactive sediment, resulting from a former radium and uranium refinery that operated alongside the Harbour, currently limits redevelopment and revitalization opportunities. These waste materials contain radium-226, uranium, arsenic and other contaminants. Several other on-land locations within the community of Port Hope are also affected by the low-level radioactive waste management practices of the past. The Port Hope Project is a community initiated undertaking that will result in the consolidation of an estimated 1.2 million cubic metres of the low-level radioactive waste from the various sites in Port Hope into a new engineered above ground long-term waste management facility. The remediation of the estimated 120,000 m{sup 3} of contaminated sediments from the Port Hope Harbour is one of the more challenging components of the Port Hope Project. Following a thorough review of various options, the proposed method of contaminated sediment removal is by dredging. The sediment from the dredge will then be pumped as a sediment-water slurry mixture into geo-synthetic containment tubes for dewatering. Due to the hard substrate below the contaminated sediment, the challenge has been to set performance standards in terms of low residual surface concentrations that are attainable in an operationally efficient manner. (authors)

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