Nuclear Waste Management Facilities: Advances, Environmental Impacts, and Future Prospects

By Rehab O Abdel Rahman

Nuclear Waste Management Facilities: Advances, Environmental Impacts, and Future Prospects examines best practices and recent trends in improving nuclear safety and reducing the negative environmental impacts of nuclear waste. With strong emphasis on regulatory requirements, this reference is essential for designing new integrated waste management practices, using lessons learned from historical and current practices.

Divided into three key sections, Part One introduces the reader to the safety and environmental impacts of the nuclear industry. Part Two reviews recent technological and methodological approaches to enhancing safety, as well as reducing the carbon footprint of both individual processes and integrated facilities. Topics covered include waste processing, transmutation and decommissioning. Part Three consider potential management schemes for special waste from innovative sources, and wastes that contain emerging contaminants, including waste recycling opportunities.

Nuclear Waste Management Facilities: Advances, Environmental Impacts, and Future Prospects is a crucial tool needed to implement the safest and most environmentally considerate best practices within nuclear waste management facilities.

• Presents recent approaches used to assess and improve the safety and reduce the environmental impacts of nuclear waste management facilities
• Offers technical guidance to support the development and defense of the environmental impact assessment (EIA) and Safety Cases to support the waste management facilities licensing throughout their lifecycles
• Highlights the future perspectives for wastes produced from innovative reactors and wastes containing emerging contaminants, and recycling opportunities

• Language: English
• Publisher: Academic Press
• Release date: Feb 24, 2024
• ISBN: 9780323960076

Rehab O Abdel Rahman

Dr. Rehab O Abdel Rahman is a Professor of Chemical Nuclear Engineering at Hot Laboratories for the Egyptian Atomic Energy Authority (EAEA) in Cairo, Egypt. She worked for more than 25 years in supporting the licensing of radioactive waste management facilities and participated in international projects on the development and implementation of safety cases and safety assessment for those facilities. Her widely published research focuses on radioactive waste management. She supervises post graduate students, teaches undergraduate courses, and supports training activities within EAEA, serves as a member in international scientific committees. She has editorial experience as a managing editor for international journals, guest editor for special issues, and editor of several books, and frequent contributor on the topic of hazardous waste management.

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Part 1

Introduction to nuclear waste management sustainability

1. Sustainability and environmental impacts of the nuclear industry 3

2. Historical radioactive and nuclear waste management practices: Analysis and insights for the period 1940–1990s 71

3. Current approaches in managing nuclear wastes: Administrative requirements and technological advances 155

Chapter 1

Sustainability and environmental impacts of the nuclear industry

Contents

1.1 Introduction 4

1.2 Role of the nuclear industry in ensuring life sustainability 8

1.2.1 Isotopes and life sustainability 9

1.2.1.1 Conservation of water 9

1.2.1.2 Air quality monitoring 12

1.2.1.3 Tracing the climate changes 13

1.2.1.4 Securing food 13

1.2.1.5 Ensuring good health 14

1.2.1.6 Advancing the industry 15

1.2.2 Fission energy and life sustainability 18

1.2.2.1 Energy provision 18

1.2.2.2 Radioisotope production 20

1.2.3 Factors that affect the sustainability of nuclear technologies 21

1.2.3.1 Nuclear power reactors 22

1.2.3.2 Nuclear research reactors 23

1.2.3.3 Particle accelerators 24

1.2.4 Spent fuel and radioactive wastes management: Multi-dimensional sustainability concerns 25

1.2.4.1 Sealed radioactive sources 27

1.2.4.2 Spent fuel 30

1.2.4.3 Unsealed radioactive wastes 34

1.2.4.4 Naturally occurring radioactive material and technically enhanced NORM 37

1.3 Introduction to safety and environmental assessments 41

1.3.1 Safety assessments 42

1.3.2 Life cycle assessment 43

1.3.3 Environmental impact assessment 47

1.3.4 Strategic environmental assessment 49

1.4 Nuclear energy sustainability assessments 51

1.4.1 Case studies on the impacts of the nuclear energy consumption on the environment and economy 54

1.4.1.1 Case study (1): Impacts of nuclear energy consumption in BRICS group members 55

1.4.1.2 Case study (2): Impacts of the nuclear consumption in G7 group members 55

1.4.1.3 Case study (3): Impacts of nuclear energy consumption in top ten ecological footprint countries 56

1.4.1.4 Case study (4): Impacts of nuclear energy in France 56

1.4.1.5 Case study (5): Impacts of nuclear energy in Pakistan 57

1.4.2 Case study (6): Impacts of nuclear energy consumption on human well-being 57

1.4.3 Case study (7): Comparative analysis of the French nuclear energy life cycle impacts 58

1.5 Conclusion 59

References 60

1.1 Introduction

Natural radiation is part of our environment; it occurs due to the decay of cosmogenic and primordial isotopes. The life on earth exists under continuous exposure to natural radiation over millions of years. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) estimated the current annual population-weighted average dose to equal ≈2.8 mSv (UNSCEAR, 2000). Of this value, 2.4 mSv originated from the exposure to natural radiation sources. These sources include those leading to external exposure, i.e., radon emitting isotopes (indoor), natural terrestrial isotopes, cosmogenic isotopes, and those leading to natural internal exposure, i.e., naturally occurring radioisotopes in our bodies such as ⁴⁰K. Fig. 1.1 illustrates the contribution of the exposure to natural and artificial radiation sources to the average annual effective dose to the population (UNSCEAR, 2000). It should be noted that the presented contribution varies from one place to another depending on the variation of the radon emitting isotopes at buildings, personal habits and geological settings, and altitude (UNSCEAR, 2000). Several researchers investigated the effects of exposure to natural radiation on living organisms. These works proved that exposure to natural radiation sources has played a role in the evolution of these organisms, develop an adaptive response to stress and to chronic stress environments, and enhanced their ability to develop defensive mechanisms at the cellular level (Fratini et al., 2015; Morciano et al., 2018; Olivieri et al., 1984; Wolff et al., 1988; De Toledo et al., 2006; Carbone et al., 2009; Zarubin et al., 2021; Wang et al., 2020; Chew et al., 2022).

Figure 1.1 Contribution of different radiation sources to the mean individual dose.

Since the discovery of the radiation and radioactivity phenomenon; scientists, engineers, and physicians are continuing their work to identify potential applications of nuclear sciences and technologies that improve human life. Their work was directed to understand the nature of the radiation, evaluate its effects on different classes of materials, and find safe and secure methods to induce radiation and control it. These efforts started by studying natural radiation, understanding the difference between fluorescence and radioactivity, trying to concentrate and purify natural radioactive materials, e.g., radium, uranium, and thorium, and finding beneficial applications to support the advancement of human life. These efforts contributed and were extended to identify the types and characteristics of different forms of radiation and develop an accurate understanding of the nuclear and sub-nuclear particles and useful applications with more details given in references (Aulenbach and Ryan, 1986; RSC, n.d.; Lawson, 1999; Forshier, 2009; Choppin et al., 2013; Reed, 2014; Abdel Rahman et al., 2014a; Abdel Rahman and Ojovan, 2021a). Within a few years after the discovery of radiation and radioactivity phenomena, the purified/concentrated natural radioactive materials were commercialized for beneficial uses such as energy sources and glowing agents. All the early uses of these materials were peaceful and targeted medical applications, e.g., skin cancer treatment, tumors, etc., and manufacturing body care products, e.g., toothpaste, cosmetics, soaps, etc. In addition, radium was widely used in the production of glow-in-the-dark paint that was used in clocks, dials, and watches, whereas uranium was used in the manufacturing of glassware and ceramics. All these early uses were not designed based on a clear understanding of the effects of exposure to radiation on human health. With the progress in understanding the different types of radiation and their effects, new types of radiotherapy devices and techniques have been developed and are continuously improved (Gianfaldoni et al., 2017; Huh and Kim, 2020). Large acceptance of radiotherapy was regained, and confidence has been built in these applications. Simultaneously, other uses of the purified/concentrated radioactive materials were prohibited, i.e., manufacturing body care products and decorations.

In parallel, other efforts were directed to induce radiation artificially by bombarding a designated non-radioactive material with specified projectile particles of certain energy. This engineered process was employed to produce radioactive isotopes and induce fission reactions. To control the quality and quantity of the radioactive isotopes and the energy produced from induced fission, the efforts were directed to design and develop devices to accelerate projectile particles, e.g., cyclotrons, and control the induced fission, e.g., nuclear reactors (Choppin et al., 2013; Abdel Rahman and Ojovan, 2021a; Chemistry LibreTexts, 2022; Scientific Sentence, 2022). These advances in the engineering of natural radioactive materials and synthesizing artificial radioactive materials created new work environments in which the workers are exposed to radiation doses higher than those caused by natural radiation, which was later linked to the increased probability of developing some health effects that depend in their nature and magnitude on the type of radiation and the exposure duration and nature (Lamarch and Baratta, 2001; Martin, 2013; Abdel Rahman et al., 2014a; Ojovan and Lee, 2014; Abdel Rahman and Ojovan, 2021a). At this point, regulations and standards started to be set both on national and international scales to protect the workers and the public from the radiological hazards of artificial and concentrated/purified natural radioactive materials. These regulations and standards are periodically checked and updated based on the best knowledge acquired at the time, the development of these standards and regulations are found elsewhere (Valentin, 2007; Clarke and Valentin, 2008; IAEA, 2014a; Abdel Rahman and Ojovan, 2021a).

During the 1940s, military uses of nuclear energy were initiated to produce weapons and to fuel submarines and aircraft carriers. The detonation of the bombs on Hiroshima and Nagasaki in Japan during the Second World War was a massacre that led to the death of hundreds of thousands of people and set a shadow on the widespread of fission technology. Since then, the isotopic (non-fission) applications continued to be developed and improved toward wide-scale industrial applications of radioactive sources. Meanwhile, nuclear energy was known as "civilian technology with military ancestors" and this has set various security and non-proliferation requirements that should be considered during the development of nuclear energy programs (Kermisch and Taebi, 2017). These measures restrained the wide spread of nuclear energy all over the world; but did not hold the nuclear energy from contributing considerably to the energy mix in several countries, e.g., France, USA, UK, etc. This was powered by the awareness of the negative environmental impacts of coal and the fear of the unsustainability of the petroleum chain supply (IAEA, 2004). Large-scale nuclear accidents took place, such as Three Miles Island, USA, Chornobyl, USSR, and others. Nuclear accidents have slowed down the spread of nuclear energy due to the fear of the radiological risks that are triggered by large-scale accidents. During the 1990–2000s, the spread of nuclear energy continued to slow down due to the potential military uses, low demand for energy, and fear of the high radiological risks of major nuclear accidents. An additional shadow on the peaceful uses of nuclear energy for power generation was left by the Fukushima Daiichi nuclear accident in 2011. Finally, by the beginning of the new century, the third generation of nuclear reactors was developed with enhanced safety features, the treaty of non-proliferation of nuclear weapons was formalized, the demand for energy increased, and sustainability awareness increased, which led to an increase in the demand of the nuclear energy (WNA, 2020).

Currently, the applications of engineered radioactive materials and induced fission are extended to support different economic sectors in our daily lives; these applications could be classified as isotopic and fission energy applications. The first includes the administration of both stable and radioactive isotopes to trace and gauge different natural and industrial processes and to irradiate materials. The latter includes the peaceful use of the fission reactions to produce energy either electricity or co-generation of different energy forms and radioisotope production (Fig. 1.2). All these applications aim to ensure life sustainability, either by supporting the advancement of human lives and/or by helping the management of natural resources in a way that ensures the sustainable development. This chapter is designed to introduce the reader to how the nuclear industry supports life sustainability, what are the factors that affect the sustainability of this industry, and how the safety and the environmental impacts are assessed and used to judge the sustainability of the nuclear energy sector. In this respect, the three following sections will provide an overview of the role of the nuclear industry in ensuring life sustainability and what are the factors that affect its sustainability with special reference to spent fuel and radioactive waste management, introduce the different methods that are used to assess the safety and environmental impacts and present a comparative analysis on the sustainability of the nuclear energy and other energy sources.

Figure 1.2 Applications of the isotopic and fission energy technologies.

1.2 Role of the nuclear industry in ensuring life sustainability

As indicated above, the continuous developments in the nuclear sciences and technologies led to the spread of a wide range of applications of isotopic and fission energy in different fields of life. These applications aspire to support the energy, agricultural, medical, research, and industrial sectors to achieve their targeted sustainable development goals (SDGs). These applications are being developed to meet the need to advance the human communities and ensure the conservation of the natural resources. They are designed according to the best of our updated knowledge to ensure radiation/nuclear safety and security. For any application that involves exposure to radiation, the exposure practice is executed according to as low as reasonably achievable (ALARA) principles, i.e., it should be justified, and optimized and the dose equivalent to individuals is limited by the legal limits. In this section, an overview of these applications will be provided and the factors that affect their sustainability will be analyzed with special reference to the radioactive waste classifications, inventory, and available safe management strategies/options.

1.2.1 Isotopes and life sustainability

Natural elements exist in the environment as a mixture of two isotopes or more of variable relative abundance; both stable and radioactive isotopes co-exist in natural samples. On one hand, the applications of the stable isotopes are dependent on the fractionation of these isotopes during their migration in different materials; this fractionation occurs due to mass and field isotopic effects (Davies et al., 2014; Wiederhold, 2015). Most of the traditionally applied isotopes are elements that exist in the gaseous phase or can easily be converted to that phase, e.g., C, N, O, S, Li, Ca, Hg, etc., which ease their detection (Davies et al., 2014; Wiederhold, 2015; Gussone et al., 2018; Tomascak, 2016; Abdel Rahman and Ojovan, 2021a; Li et al., 2022; Rodushkin et al., 2022; Hoefs and Harmon, 2022). On the other hand, applications of the radioactive isotopes rely on the emitted radiation characteristics, i.e., type of radiation, half-life, and the chemical and biological behavior of the element. Radioactive isotopes can be used in different phases, i.e., solid, liquid, or gaseous. Examples of the radioactive isotopes include ¹²⁵I, ¹³⁷Cs,¹⁹²Ir, etc. Natural stable and radioactive isotopes are mainly used to trace the natural process to clarify our understanding of the historical natural processes, e.g., geochronological research. Some engineered radioactive isotopes are also used in this respect, yet the engineered isotopes are mainly used in tracing industrial processes, gauging, and irradiation applications.

1.2.1.1 Conservation of water

No life without water, where water is a vital compound to all the biological processes within living organisms, hence water is the most important natural component that exists on earth. Despite water covers nearly 71% of the earth's surface, only 0.3% of this water is fresh and easily accessible. Subsequently, water conservation is considered to be crucial for the sustainability of life and it is the driving force to ensure the achievement of most of the SDGs. The 6th goal in the SDG aims to ensure the provision of clean water and sanitation which is not a standing-alone goal as this provision of clean water is also needed to achieve the 2nd, 3rd, 8th, and 9th SDGs, namely; zero hunger, good health and wellbeing, decent work and economic growth, and industry, innovation, and infrastructure (Abdel Rahman et al., 2022). This goal is also very much related to placing controls on pollution sources and preventing their spread in the bio- and geo-sphere which are vital to have sustainable cities and communities, and safe life below water and on earth and cannot be achieved without partnerships for the goals (11th, 14th, 15th, and 17th SDGs) (Abdel Rahman et al., 2022). In this respect, the conservation of water could be accomplished by adopting a good water management plan and preventing the water reservoirs from being contaminated, i.e., ensuring water quality.

Since the 1950s, isotopic applications of both stable and radioactive isotopes were introduced to study the hydrological cycle to provide a reliable tool for water management and ensure water quality (Ortega and Laura, 2019). These studies were directed to identify the water origin, determine the mixing processes and its pathways, and quantify the dissolved components (Abdel Rahman et al., 2014a; IAEA, 2000a, 2006; Hoefs, 2009; Rozanski and Froehlich, 1996; Khayat et al., 2020; Abdel Rahman and Ojovan, 2021a). The hydrological cycle could be described as follows:

• Water is subjected to evapotranspiration from surface waters, e.g., rivers, lakes, oceans, etc., the soil, and the plants into the atmosphere.

• The vapor is transported to higher altitudes and latitudes, where it cools down and condenses.

• Marine vapor is mostly precipitated over the oceans and the rest of the vapor is transported over the continents.

• The transported vapor is precipitated over surface water, the soil, and as ice.

• The precipitated water is further evaporated, transpired, or drained by surface runoff, infiltration, and percolation.

Hydrogen and oxygen are the forming elements of pure water; hence the fractionations of their isotopes within the hydrological cycle due to the evaporation and condensation processes are used to trace the circulation of water and conclude on the groundwater recharge, surface water dispersion, surface and groundwater interactions, and groundwater dating. Fig. 1.3 presents an illustration of the change in the isotopic composition of water through the hydrological cycle (Jung et al., 2020).

Figure 1.3 Diagram of isotopic composition change within the hydrological cycle (From Hoefs, 1997; Coplen et al., 2000; Jung et al., 2020).

As the water is circulated in different compartments, e.g., atmosphere, geosphere, and biosphere, it comes in contact with other materials. This allowed the employment of other stable and radioactive isotopes of different main or trace elements in each compartment to trace the hydrological cycle. For example, in the atmospheric compartment; hydrogen, nitrogen, oxygen, carbon dioxide, methane, and noble gases are considered as main components that have biogenic or anthropogenic sources. Carbon monoxide, sulfur species, and ozone are considered trace elements that have biogenic, anthropogenic, chemical, or photochemical sources (Hoefs and Harmon, 2022). To trace the hydrological cycle in the atmospheric compartment, besides oxygen and hydrogen isotopes, carbon is used to trace the dissolved components, and noble gases are used for dating (Zhou and Ballentine, 2006; Li et al., 2017; Zhang et al., 2019; Abdel Rahman and Ojovan, 2021a; Hoefs and Harmon, 2022). Table 1.1 lists the applied natural (N) and engineered (E) stable and radioactive isotopes used to support the water management planning; their half-lives and potential applications (Abdel Rahman and Ojovan, 2021a).

Table 1.1

⁎N, natural isotope.

⁎⁎E, engineered isotope.

In addition to these applications, ionizing radiation has been employed in controlling water pollution. In this respect, gamma and neutron irradiation units have been installed in a limited number of wastewater treatment plants to degrade persistent contaminants in different wastewater streams. These applications are employed to treat and disinfect agricultural wastewater, textile effluents, municipal wastewater, pharmaceutical and petrochemical effluents, and sludge. Their economic and technical feasibility was proved and their nuclear safety was confirmed (IAEA, 2003a, 2008a, 2018b; Abdel Rahman and Hung, 2020; Gryczka et al., 2021; Negrete-Bolagay et al., 2021; Priyadarshini et al., 2022).

1.2.1.2 Air quality monitoring

With increased industrialization and urbanization activities, various types of pollutants were released into the air. These pollutants include sulfur oxides (SOx), nitrogen oxides (NOx), volatile organic compounds (VOC), ground-level ozone, carbon monoxide, and particulate matter. They are not only affecting human health leading to a sensible increase in the probability of developing fatal respiratory and cardiovascular diseases, but also these pollutants impact the ecosystem deeply as they lead to acidic rain and deposition of nitrogen and toxic pollutants that intrude the ecosystem. Subsequently, air pollution is recognized as a sustainability concern that affects the 3rd and 11th SDGs (good health and sustainable cities and communities) (Rafaja et al., 2018). In addition, due to their effects on the ecosystem, they also affect the productivity of the land, and life below water and on land (2nd, 14th, and 15th SDGs).

In the atmospheric compartment, the concentration of the chemical species is affected by the following processes (Hoefs and Harmon, 2022):

• Dry and wet deposition processes.

• Formation or removal due to chemical reactions.

• Emissions from natural and anthropogenic sources.

These processes can cause isotope fractionation that may continually break apart and recombine in a multitude of photochemical reactions. In this respect, carbon, nitrogen, oxygen, noble gases, and sulfur isotopes are used to identify the source of air pollution either natural or anthropogenic, monitor pollutant pathways, predict their distributions, and estimate their impacts on the ecosystem (Zhang et al., 2021).

1.2.1.3 Tracing the climate changes

Notable changes in temperature and weather pattern shifts are recorded all over the world, where the increased industrialization and urbanization that started in the 1800s are responsible for these changes. They can affect human life sustainability, the quality of life, and the ecosystem. Hence, the 13th SDG was assigned to combating climate change and its impact. Isotopic techniques are employed to understand the nature of climate change by recording the environmental conditions on earth currently and historically over a large period of time. This effort is achieved by identifying pollution sources' signatures; budgeting the ocean carbon cycles; recording ocean temperature; identifying the volumes of the ice sheets, and dating marine sediments, corals, polar ice, and ice cores. The information provided by the isotopic record on the ocean temperature, salinity, and biodiversity supports the verification and improvements of the ocean and climate models (Abdel Rahman and Ojovan, 2021a). Examples of understating the impacts of climate change and combating these impacts are given in the next subsection.

1.2.1.4 Securing food

The impacts of the climatic changes on the environment are clearly sensible in the reported long drought periods, reduction of arable land and freshwater, soil erosion, and saline water intrusion. These phenomena heavily disturb the quality and quantity of land and animal productivity hence affecting the efforts to secure food. The isotopic techniques are employed to understand the impacts of climate change on the agricultural sector and to adapt and combat these impacts, Fig. 1.4 illustrates some of the widely employed efforts in this field. In these applications, different stable and radioactive isotopes are employed. Examples of these isotope applications are: ³²P which is used to trace the fertilizer's behavior and measure its efficiency, determine the rate of microbial protein synthesis, and mineral imbalance in farm animals; ¹²⁵I, which is used in radioimmunoassay of body fluids, etc. (Zapata, 1990; Abdel Rahman et al., 2014a; IAEA, 2012a, 2015a, 2018a, 2022a; IAEA-FAO, 2016; Abdel Rahman and Ojovan 2021a).

Figure 1.4 Examples of the applications of isotopic techniques to secure food.

1.2.1.5 Ensuring good health

Ensuring good health is a very complicated goal, where it is reliant on the provision of a clean environment, e.g., clean water, air, and soil, and ensuring the availability of good nutrition, and a good lifestyle. As indicated in Section 1.1, the use of radiation in medical applications started at the early age of discovering ionizing radiations, where the applications focused on radiography and radiotherapy. With the continuous understanding of ionizing radiation and its effects on biological cells and the advances in manufacturing radioisotopes, several engineered radioisotopes were employed to treat, prevent, and diagnose various medical conditions. These applications are executed to ensure public and worker safety. The isotopic techniques used include applications in radioimmunoassay (¹²⁵I, ⁵⁷Co, ³H, ¹⁴C, and ¹³C), transmission and emission tomography (⁹⁹mTc, ²⁰¹Tl, ¹²³I, ¹³³Xe, ¹¹¹In, ⁶⁷Ga, ¹⁸F, ¹¹C, ¹³N, and ¹⁵O), radiopharmaceuticals (¹³¹I, ³²P, ⁸⁶Re, and ¹⁶⁹Er), brachytherapy (¹⁹²Ir, ¹³⁷Cs, ¹²⁵I, ¹⁹⁸Au, ¹⁰⁶Ru, and ¹⁰³Pd), boron neutron capture therapy, magnetic resonance medical imaging, and medical sterilization (OCED, 1998; Choppin et al., 2013; Abdel Rahman and Ojovan, 2021a).

1.2.1.6 Advancing the industry

Isotopic techniques are widely employed to trace and gauge industrial processes and irradiate materials. They aim to enhance productivity in terms of quality and quantity, ensure the security of the workplace, and provide insights into the system behavior towards having improved industrial processes. They are based on the penetrability of radiation through the material and subsequently depend on the material's properties. Different types of irradiation sources are applied including alpha, beta, gamma, and neutron sources, and could be categorized based on the type of the used radioactive source, i.e., open radioactive sources or sealed sources, or the nature of the device, i.e., fixed or movable devices, and place of application, i.e., online and offline. Some of these applications are as follows (Machi et al., 1983; OECD, 1998; Abdullah, 2005; IAEA, 2003a, 2008a, b, 2020a; Abdel Rahman et al., 2014a; Abdel Rahman and Ojovan 2021a; Bonechia et al., 2020):

• Control systems: These are widely applied in different industries to gauge and control several product properties. They employed sealed radioactive sources that are not in physical contact with the measured samples. Subsequently, these systems are easily applied under extreme operating conditions (e.g., high pressure, high temperature, and corrosive media). Moreover, they are characterized by their neglected maintenance outage and excellent cost-benefit ratio. Examples of these systems are listed in Table 1.2.

• Analytical instruments: These are widely used to trace industrial processes either by using laboratory or portable devices. They employed sealed radioactive sources and are used in X-ray fluorescence (XRF); soil moisture/density meters; and oil well logging. XRF is used to determine the chemical composition of the materials and is widely used in the mining and industrial sectors and in general chemical analysis laboratories. It relies on radioisotopes that decay by electron capture, alpha, or gamma ray. A soil moisture/density meter is a portable analytical tool that is used to support civil and agronomy engineering. These applications rely on using neutron or gamma-emitting radioisotopes. Finally, different gamma and neutron emitting sources and their hybrid techniques are used in oil well logging to provide in-depth characterization of the site.

• Quality systems: Different techniques are used in this field to allow the characterization of the quality of some industrial processes via calibrating the used radioactive sources and applying industrial radiography. Other applications include troubleshooting assessment, process optimization, and planning for the predictive maintenance of the distillation, absorption, and stripping columns via the use of a suitable gamma/neutron emitting sealed source for column scanning. Examples of these systems are listed in Table 1.2.

• Tracer applications: A very small amount of radioactive isotope is introduced into the process or the system that needs to be studied and is traced using a suitable detector. The applied radiotracers are mostly characterized by their short half-life that enables their decay within a considerable short time. This class of applications is employed in chemical synthesis research laboratories, the oil and gas industry, and mineral processing. It is mostly used to determine process control parameters and equipment performance. ⁴¹Ar, ²⁴Na, and ¹⁹⁸Au are examples of tracers that are used to trace gaseous streams, aqueous solutions, and solids, respectively.

• Security and safety systems: Neutron-gamma sealed sources are used to detect explosives in airports, harbors, and railway stations. In addition, tritium was used in the manufacturing exit sign. Moreover, smoke detectors are essentially used in public areas, e.g., airports, hospitals, museums, and concert halls, to ensure the safety of the public. Table 1.2 lists these applications.

• Industrial irradiators: In addition to the industrial irradiators that are used in medical (Section 1.2.1.5) and agriculture (Fig. 1.4) sterilization applications, irradiators and accelerators are applied in cross-linking different types of polymer-based products, e.g., wires and cables, polyethylene foam, heat shrinkable tubing and sheets, wood/plastic composites, polymer flocculent, etc. The cross-linking process achieved by accelerators is considered green, as they have small footprints in terms of the use of chemicals and waste generation.

• Power sources: These are used to generate electricity for long-distance space probes, satellites, and underwater listening devices for military uses. They utilize a sealed source, where the decay heat is converted to electricity using a thermocouple device.

• Muography: Imaging methods based on the absorption or scattering of atmospheric muons known as muography exhibited a steep rise in recent years in a variety of applications aimed at studying the interior of natural or artificial structures important within geotechnical investigations, nuclear waste characterization, homeland security, and natural hazard monitoring.

Table 1.2

CR, computed radiography; CT, computed tomography; DR, digital radiography; RTR, real-time radiography.

1.2.2 Fission energy and life sustainability

Fission reaction naturally occurs at a very low rate, in heavy nuclei where the parent radionuclide splits to produce two fission fragments and some neutrons; the number of the produced neutrons is dependent on the distribution probability of the fission process. Fission is induced artificially by bombarding a target nucleus with neutron, proton, or photon, where the first operating nuclear reactor was built in 1942 to induce and control the fission reaction (Lamarch and Baratta, 2001; Martin, 2013; Abdel Rahman et al., 2014a; Ojovan and Lee, 2014; Abdel Rahman and Ojovan, 2021a). Fission energy is peacefully used to produce electricity, other non-electric energy products, and radioisotopes (Fig. 1.2). These products are usually obtained from nuclear research or power reactors, where the radioisotopes and electricity are the two well-known products from these reactors, respectively. In addition, nuclear research reactors are widely used in providing neutron activation analysis, supporting the research and development in geochronology, transmutation, neutron therapy, neutron scattering, and material and fuel irradiation, and in teaching and training. Nuclear power reactors are proven to generate district heat, industrial process heat, and hydrogen and have a good record in