Nuclear energy is one of the most efficient and effective sources of energy with a promising future. This assumption is backed by the research that aims to exploit higher potentials in the nuclear energy sector. There arise a lot of challenges regarding the development of nuclear power. The disposal of radioactive waste that is produced during the process of generating the energy is the major issue.
This paper explores management of radioactive waste and the importance of handling waste that is produced by nuclear power stations. In addition, the paper explains the seriousness of waste management, the sources of radioactive wastes and their classes, and analyzes the incidences that involved radioactive wastes.
Nuclear energy is one of the most effective and most efficient kinds of energy in the world nowadays. The production of this source of energy, however, comes with various challenges that must be addressed and solved. One of the major problems that have been encountered as far as the nuclear energy is concerned is the disposal of radioactive materials. Due to the nature of the harm that people and the environment can be subjected to as a result of poor radioactive material disposal, measures of handling these wastes must be put into place by developing safe methods of disposing these materials in order to avoid casualties and injuries. This paper will explore ways of managing radioactive wastes and disposing them safely. Then, paper will discuss the sources of radioactive materials and the importance of their managing.
The main objective of this paper is to explain the importance of managing radioactive waste, describe the sources of radioactive wastes, classify radioactive waste, and give information about the incidences that are related to this topic.
Data Collection Methods
Various methods were used to collect information for this study. The study heavily relied on the Internet to gather information about management of radioactive materials. Peer reviewed documents about management of wastes were also studied and all the information that was needed for the report was obtained. Government websites and websites of international bodies that are involved in management of nuclear energy and radioactive materials were also accessed to gather information for the research. In addition, printed electronic documents as well as online libraries were also some of the important resources used in the study.
The development process of nuclear energy produces waste that is radioactive in nature in all the stages of its development (Giusti, 2009). Management of the wastes that are produced during various successive stages is challenging and needs well laid down plans and procedures to avoid contamination of the environment. Over the decade, radioactive sources have been on the rise, leading to increased production of radioactive wastes and increasing the danger to the health of living things. Due to large-scale production of radioactive wastes, the main concern has been the disposal of these materials in a safe manner without affecting the ecosystem. Substances with radioactive components are known to be harmful to humans and the environment as they can cause various injuries and health problems to all living species in the ecosystem. The release of radioactive materials is accompanied by radiation that exerts far reaching effect to the environment. Radiation is a process of spontaneous disintegration of unstable nuclei that release radioactive particles to either soil, water, or the air (Spinks & Woods, 1990). Most of radioactivity incidents occurred in the past. Major accidents occurred in nuclear power plants where various nuclear products are manufactured and used. There are plants that work on weapon systems or produce energy for civilian and industrial use (Jauffret, n.d).
Reports indicate that various living and non-living things near nuclear power stations have been contaminated with radioactive materials. The amount of waste produced by nuclear plants is small. However, the problem is that its radioactive nature can be extremely harmful and able to cause adverse effects and injuries if one is exposed to such environment. Even though little fuel is used in the process of producing nuclear power, the end product is likely to be highly powerful and harmful. Radioactivity, therefore, is a natural process in which isotopes of a given atom lose stability and energy, which causes radiation in the form of gamma, beta, and alpha particles (Khan, 2014). According to Khan, all isotopes are not necessarily radioactive, but isotopes that are produced by nuclear energy are highly radioactive.
Management and regulation of radioactive materials and hazards that are caused by these materials is a national, regional as well as an international responsibility that requires collective efforts in order process them successfully. Despite the impacts that might result from radioactive substances, there are still a lot of beneficial applications of nuclear energy, which include generation of power, medical applications, agriculture as well as other industries. Due to the danger and accidents that might be caused by these materials, production, management, transportation, application, and installation of these materials should be done in a professional and careful manner to prevent accidents and disasters like some that have been already experienced.
Radioactive wastes can be classified into low, medium, or high level radioactive wastes according to the amount of radioactivity that they emit. This classification according to Institute of Energy and Environmental Research is based on the origin of the waste rather than its physical and chemical component that determines its management. Highly radioactive waste, for instance, is the waste with high levels of activity and a high concentration of radionuclides that can generate relatively enormous quantities of heat as a result of a radioactive decay process. Another category is intermediate level waste, which has a significantly high degree of long lived radionuclides that should be isolated as they are not easily decaying. Hence, they require careful methods of disposal, for example, in greater depths to avoid leakage to the surface and contamination. In comparison to the intermediate level waste, low level waste, which is another level of radioactive materials, is waste that has a high radioactive content, but this level of waste has a considerably low amount of long lived radionuclides that may require containment for only a short number of years. Waste with extremely low radioactivity content is referred to as exempt waste, and it is not as dangerous as high level waste and low level waste as it is stated by Energy Nuclear Regulatory Group. This waste has radioactive materials that are considered harmless to people and the ecosystem (ENSREG, n.d.).
Nevertheless, they need to be contained for a very short time before they can finally decay. Very short lived waste is the kind of waste whose time of decay after storage is just a few years. After that period, the waste can be cleared from the regulatory facility and disposed. This class of waste contains materials that have radionuclides that consist of short half-live and are used for research and medical purposes according to International Atomic Energy Agency. Very low level waste is another class of waste that cannot be treated as exempt waste but also does not need a high level of containment as high level waste. Due to its little amount of radioactive content, the waste can be disposed in near surface facilities as it is not very dangerous to the environment and people.
There are several methods and capacities of containment for each of the above mentioned categories of radioactive wastes. Those that are highly radioactive require more sophisticated methods of disposal due to the presence of long-lived radionuclides that can cause harm for years if they leak to the environment.
Sources of radioactive waste.
The main sources of radioactive materials are nuclear power plants; although some radioactive content comes from other minor sources such as hospitals, research facilities, and naturally existing forms of radioactive materials. An average nuclear power plant generates approximately 20 metric tons of used nuclear fuel, while the entire industry generates from 2000 to 2500 metric tons of the same nuclear fuel per annum. This data indicates how high the amount of nuclear waste is being produced and exposed to the environment every year by nuclear energy reactors and plants. Radioactive waste is generated through a number of different ways and facilities and a wide variety of physical and chemical waste that contain a wide range of radionuclides. Radioactive waste is mainly a by-product produced during the generation of nuclear energy and applications that are involved in nuclear fission and research. Over time, radioactive waste decays, releasing hazardous components to the environment.
If not carefully disposed, radioactive components such as plutonium are the main source of radioactivity, which are known to be hazardous to human beings and the ecosystem as they contain materials capable of remaining radioactive for millions of years, producing radiation. Radioactive waste also originate from nuclear power plants, nuclear weapons, and fuel treatment plants where various nuclear fuel circles take place during processing and manufacturing of weapons. They produce radioactive waste at the end of the circle. The extraction of uranium produces alpha-emitting waste that contains radium and its decay products. If not completely purified or stored safely as it is done in the United States, health risks can be extremely serious and include severe injuries and even deaths. The waste from medical as well as industrial processes is also radioactive. In addition, radioactivity is present in coal, gas, and other minerals.
Nuclear weapons are also blamed for contributing to high levels of radioactivity. Some of the atomic bombs that have been created in developed and developing countries and other products of uranium are cause considerable concern in the world. That is why, international organizations as well as individual countries adopt laws that are targeted to reduce access to plutonium and manufacturing of weapons if certain restrictions have not been met. Nuclear weapons, which consist of huge amount of gamma and beta particles that emit actinides used in bombs, are also one of the main sources of radioactivity as they contain materials such as pu-239, which is highly radioactive. Geological activities associated with mining as well as military programs that were carried out in the past also produce radioactive materials today. Legacy waste, for instance, is one of the greatest contributors of radioactive contamination.
According to the report by Greenpeace (2010), Centre de Stockage de La Manche in France and Yucca Mountain in USA, which have been designated by the respective governments as nuclear waste disposal sites, have shown evidence of leakage, and Yucca mountains site was shut down in 2011 by the Obama administration due to health concerns posed by the facility. Also, Centre de Stockage de La Manche stores approximately 50000 cubic meters of radioactive materials. The reports based on the investigation carried out on the site in 2006 indicate that water contaminated with radioactive materials have been leaking via an underground aquifer, putting lives of living organisms in the area in great danger. This indicates that sites that are used for storage of these materials are also sources of radioactive materials.
Biomedical materials from laboratories as well as other institutions are some of the sources of radioactive materials too. Hospitals in this regard and other health institutions produce some wastes from materials that have been used there. Radioisotopes used for diagnosing and therapy, for example, are sources of radioactive materials. Healthcare institutions, according to NCBI, use technetium, iodine, fluorine, tritium, and carbon, all of which contain some amount of radioisotopes. Most of radioactive wastes from hospitals are either in liquid, gaseous, and solid forms. The solid sources include syringes, needles, gloves, and cotton together with other absorbent materials such as wool that also release radioactivity. Research, however, have been limited to the radioactive materials that are produced by the reactors, without taking into consideration small amounts of those that are generated in other areas, such as biomedical appliances. It means that the report made the entire process of analyzing managing waste and it safe disposal incomplete. Additionally, medical research laboratories produce waste that contains biomolecules contaminated with radioactive components, which should be isolated from the environment. Unwanted biomedical waste from these laboratories such as sharp objects and blood are considered as radioactive agents and should therefore be well disposed.
As stated before, some natural substances contain traces of radioactive materials and these include coal, oil, and gas. Coal, for instance, contains a small amount of uranium, potassium, barium, and thorium, which release radioactivity due to impurities they contain. If burned, radioactive substances in coal, despite their small amount, may be inhaled by living things and case diseases such as cancer. Residues from oil and gas are also one of the known sources of radioactivity as they have some amount of radium. Furthermore, water from oil mines may contain some amount of radon, which while decaying causes naturally occurring coatings to the pipes that are used to channel oil and its products from the mine. These are sources of natural radioactivity.
All the above mentioned sources of radioactivity need closer monitoring and research as some of them produce significant amount of radioactive materials, which may not appear hazardous, but in the long run is likely to cause health problems and injuries to human beings and all other living things.
Nuclear energy has been known for generating electricity for home appliances. This is one of the advantages that has incited numerous countries, mostly developed ones, to invest in nuclear power. It releases no greenhouse emissions, reducing the level of environmental pollution. However, despite the fact that nuclear energy has a lot of advantages, several challenges have been encountered due to the waste that originates from nuclear power plants. Wastes that are generated from nuclear power plants have radioactive components, and if one get exposed to them, they can receive injuries and die. This poses a threat to a normal way of live of people and requires high awareness and safety measures.
With their ability to last for over thousands of years, nuclear wastes need a well-defined method of disposing them in specially designed cylinders to avoid leakage of radioactive materials that may harm the environment. Leakage of radioactive materials to the atmosphere has adverse effects on the lives of animals and plants. Reportedly, such materials have been blamed for cancerous growths and genetic problems that afflict humans and animals. Therefore, poor methods of disposing radioactive materials have great impact on living things and the environment in general. Reports by the US government, for example, point out the cause of various kinds of cancer to radioactive materials human beings are exposed to. 22 kinds of cancers are linked with nuclear contamination. Workers that work in environments where radioactive materials are handled, such as nuclear power plants, put their lives at risk and have higher chances of getting cancer. Industrial and military facilities are also some of the places where people are likely to be faced with radioactive materials, which impact their health.
Radiation at these facilities is likely to cause either short term or long term injuries, depending on the level of exposure that one has been subjected to. Some effects from radioactive materials are likely to be transferred to future generations. Some of the short-term symptoms of radiation may include vomiting, nausea as well as diarrhea, which can either be fatal or mild, depending on the level of exposure. Radioactive materials are also likely to explode if they lose their stability. Accidental leakages from nuclear reactors in both military and civilian facilities have released serious mutagenic materials that have various effects on the ecosystem. Thyroid cancer, for example, and mental retardation is caused by exposure to radiation and exposure to radioactive materials. In addition to cancer and other health complications that are caused by exposure to radioactive materials, other living organisms also have suffered greatly as a result of exposure to such dangerous materials from nuclear power plants. One of the perfect examples is the Daiichi nuclear power plant in Japan, where fish were highly contaminated by the radioactive materials that leaked to the ocean.
In addition to various diseases that are caused by exposure to radioactive materials, such as cancer, the influence of these materials in the environment also is extremely significant. Water and soil pollution, for instance, are some of the impacts of radioactive materials caused by various nuclear facilities worldwide. These radioactive materials produce carcinogenic materials that are harmful and capable of lasting for many years, affecting the environment and the organisms.
Various accidents that involve radioactive materials occurred in the past. One of the most famous accidents involving radioactivity is the infamous Chernobyl nuclear power plant accident of 1986 in Ukraine. The resultant accident was blamed on the flawed design of the reactor and the facility being operated by unskilled personnel. The steam explosion and fire are claimed to have released an approximate nuclear reactor core of 5 percent to the atmosphere, killing 2 people on the spot while 28 more died later due to the injuries and exposure to radiation during the process of handling the accident. Near the accident site, a number of people have been diagnosed with thyroid cancer long after the accident and the disease is blamed on the radiation from the site.
Three Mile Island is a famous nuclear accident in the history of the United States. The accident was started by the failure of the pressure valve in the Unit-2 reactor. The pressure valve failed to close, leading to the contamination of cooling water that penetrated nearby buildings. The leakage caused high overheating of the reactor as a result of the drop in the level of cooling water. Consequently, overheating led to the leakage of several gallons of radioactive materials into the basement of the reactor building and other surrounding structures. It is estimated that more than 700000 of radioactive contaminated cooling water leaked to the reactor building and tanks that surrounded the area. Also, small amount of radioactive materials was released to the atmosphere (Foner & Garraty, 1991). Despite the dangerous nature of the accident that occurred in the area, there was no injury that resulted from the accident. The research and various studies state that there is no direct health issue or any other problems caused by the accident that occurred in the area. There were only financially related problems. People who directly lost their finances due to the accident have, however, been compensated by the government of the United States (NEI, 2014). Below is the Figure 1 that explains graphically the occurrence at Three Island Facility.
Figure 1. Three Mile Island reactor-2.
Fukushima nuclear disaster is the latest nuclear accident that has occurred in the current decade. The accident took place on 11th of March 2011 as a result of the tsunami, which was triggered by an earthquake with a recorded magnitude of 9.0 on Richter scale and had a great impact on the northern part of Japan, the areas where Fukushima is, Iwate, and other surrounding areas. The Fukushima nuclear accident is considered the worst accident after Chernobyl. The nuclear power plant is situated at the Pacific Coastline and it was hit by the tsunami, which lead to complete damage of the facility. The electric power supply as well as the inlets and outlet pipes of the plant were completely destroyed, which resulted in the leakage of the radioactive material. The reports have pointed out that radioactive substances were spread outside the nuclear facility. The malfunction of the cooling system released steam that filled up the facility and high pressure spread the radioactive materials to the environment through the openings that appeared after the explosions caused by internal pressure. It is estimated that about 800000 gallons of radioactive materials were released to the atmosphere. The government made efforts to evacuate citizens to safer places to avoid contamination. The government of Japan has reported that a radioactive material called cesium had contaminated about 12000 square miles, causing the evacuation of people from extensive affected areas. They had to abandon the cities and their work, for example, in the spheres of agriculture and business. The accident led to the disruption of the Japanese economy as a lot of funds were used for relocation and compensation of the affected people. The amount of cesium pumped into the Pacific also contaminated fish. The fish there was found to be contaminated by the research. However, there have been found no deaths and sicknesses associated with radiation on the site so far, but there have been concerns about the future diseases and deaths as a result of the effects caused by radiation from the nuclear plant.
Other accidents that occurred in nuclear facilities include Erwin in the United States, where about 40 liters of enriched uranium leaked as they were being transferred, and Tomsk in Russia, where excessive pressure led to mechanical failure in the facility.
The above incidences prove how dangerous to human as well as other living things the exposure to radioactive waste can be. The Chernobyl and Fukushima accidents, for example, are the worst tragedies that have hit humanity as far as nuclear energy is concerned. Safety measures have been taken to ensure that human beings do not suffer from radioactive contamination, death, and evacuation from their homes.
Management of radioactive materials is a complex and an expensive process that requires not only dedication but also considerable skills as well. Radioactive materials decay for tens and thousands years. Therefore, special technologies are needed to dispose this kind of waste since they have an adverse effect on the environment and the health of all living things. These profound effects can last for a long time. Managing radioactive materials involves isolating them or storing them in areas that do not pose danger to human beings as well as the environment. Some of the methods that are used to manage radioactive materials include deep burial beneath the earth’s surface, where they cannot cause harm, in special containers to avoid leakage to underground sources of water, such as aquifers among others. This section of the paper provides methods of managing radioactive waste and rules that have been developed to handle it and nuclear facilities. The section also describes methods that can be used to dispose radioactive materials.
Since radioactive materials are leftovers of the nuclear materials that have been used in various operations, radioactive materials vary in magnitude as well as the adversity of the effects they afflict the environment. Regulation of these wastes is therefore subject to management and regulations of the government as well as scientific bodies that are mandated to manage radioactivity and nuclear related facilities both at a local as well as international level. World Nuclear Association, for instance, is the body that is made up of various countries and is mandated with overseeing and promoting global nuclear industry and checking the activities of nuclear facilities as well as handling radiology and other factors, such as disposal and recycling of waste from nuclear plants. Additionally, the organization is involved in checking the design of nuclear reactors to avert the situation that was experienced in Chernobyl, which was blamed on the design of the nuclear reactor.
Handling of radioactive materials depends on the type of material. Alpha and beta radionuclides, for instance, are easier to handle since the period of their decay is shorter. Radioactive materials with alpha and beta radionuclides release more gamma-rays but have shorter half-lives and tend to decay quickly into less or non radioactive elements. The US department of Energy, for example, is responsible for developing rules and regulations pertaining to the management of nuclear waste and developing disposal facilities for managing radioactive materials from used uranium fuel in the United States. Various countries also have different policies of handling radioactive waste, which are targeted at reducing the impacts of these materials. International laws concerning management of radioactive waste are also enforced to monitor the use and disposal of radioactive waste. In France, for example, the law requires that nuclear waste is reused or recycled, Canada and Switzerland, on the other hand, require that the nuclear waste facilities are accessible and the waste material is reversible in future. The nuclear waste facility must be able to meet predefined conditions of safety. India requires that radioactive materials containing high level of radioactive waste are buried deep in safety containers inside the earth’s surface. Germany, in its turn, uses Pacific salt domes to dispose the used fuel from nuclear facilities to keep it safe.
Recycling is one of the most famous methods that are used to reduce the level of radioactivity in the used fuel. France and the UK, for example, require that fuel that has been used to reduce the level of radioactive isotopes is recycled. Reprocessing of the used fuel from the nuclear industries extracts fissile materials and reduces the radioactive content of the nuclear waste. Reprocessing also produces fuel that can be reused in nuclear power plants. According to the World Nuclear Association, the main reason for reprocessing of used fuel is to recover unused plutonium and uranium. This reduces the wastage of unused resources in the fuel and minimizes the use of fuel in the nuclear facilities. The figure below shows various steps that take place during reprocessing of fuel in a nuclear plant.
Figure 2. Steps of reprocessing.
Another famous method that is used for the disposal of nuclear waste is burying the waste deep in a safe environment under the surface of the earth, where no contamination will occur for as long as the radioactive material is left underneath. However, policies in some countries require that radioactive materials that have been buried deep underneath are left accessible in case there is a need to retrieve it. Countries such as the United States, for instance, have various facilities where nuclear waste is buried such as Yucca Mountain, whose main purpose was to store high level radioactive waste. Burying of radioactive waste is considered the safest method of disposing the material of all other methods of disposal as it minimizes the chances of leakage and contamination of the environment. Some countries, like Germany, bury the waste from nuclear power plants in salt domes of the Pacific since salt domes are known to be impermeable, locking of the radioactive waste for many years.
Near surface disposal methods are used to dispose materials with a low level of radioactivity f.
In this method of disposal, special containers are used. When the containers are full, they are sealed off and covered with topsoil and possibly venting systems are used to drain gas. This method, however, is likely to be affected by long term environmental conditions such as glaciations and is suitable for disposing materials whose radioactivity can only last no longer than 20 years. Deep geological disposal, on the other hand, is a disposal method in which deep geological sites are chosen as disposal sites for radioactive materials. Stable geological sites, which are deep enough, are selected to dispose materials that have a high level of radioactive materials a long period of decay. Barriers such as rock, salt, or clay isolate the materials and prevent radionuclides from reaching the environment and affecting living things.
Mined repositories for storing radioactive materials are also some of the methods used for disposal. According to this method, repositories, which are made up of tunnels, are used as storage locations for radioactive materials since they are deep enough and safe for disposal of radioactive materials. An alternative method of storing high level waste is the use of waste containers that are then surrounded by bentonite cement to provide a barrier against radioactive materials and protect the material from contaminating the environment or leaking. However, deep geological repositories remain the most preferred alternative for disposal of radioactive materials with high level of radioactivity in numerous countries.
The most important role that management of the radioactive waste plays is ensuring that exposure to the environment is as limited as possible and reducing the levels of accidents that occur from contamination of these materials. The policies that have been developed to manage radioactive materials are essential for keeping the health of human beings and the environment safe from diseases such as thyroid cancer, which are brought about by radioactive materials. Effective management of radioactive materials reduces the amount of money that is spent on treatment of diseases that are caused by such exposure. Without proper management of nuclear waste, a large number of injuries will occur, leading to deaths of human beings and other living organisms. With the increasing amount of radioactive waste, which is a result of the rising number of nuclear power production, cleaning up the environment from poor disposal of these materials is a very crucial step towards ensuring safety of the inhabitants of the earth at present as well as in the future. One of the big roles of organizations that are involved in management of radioactive materials is checking the limits of radioactivity of the waste produced by various companies so that it does not exceed certain limits before they are considered for disposal. Generally, managing waste is a very important factor that determines survival and health of the living organisms as well as the environment.
The report was focused on studying radioactive materials and ways of managing these materials to reduce exposure of humans to the adverse effects caused by radioactivity. The report has discussed various sources of radioactive materials and the importance of managing waste that is produced by nuclear facilities. Furthermore, the report has outlined and described various accidents that involved nuclear materials and methods of disposing radioactive materials safely to avert accidents that might occur as a result of poor radioactive waste disposal. Throughout the report, it is evident that government institutions as well as private and international bodies are instrumental in managing waste and developing various policies set up to guide the processes of designing and handling nuclear power plants and reactors in particular.