Nuclear safety is defined by the International Atomic Energy Agency (IAEA) as "The achievement of proper operating conditions, prevention of accidents or mitigation of accident consequences, resulting in protection of workers, the public and the environment from undue radiation hazards". The IAEA defines nuclear security as "The prevention and detection of and response to, theft, sabotage, unauthorized access, illegal transfer or other malicious acts involving , other radioactive substances or their associated facilities".IAEA safety Glossary – Version 2.0 September 2006
This covers nuclear power plants and all other nuclear facilities, the transportation of nuclear materials, and the use and storage of nuclear materials for medical, power, industry, and military uses.
The Nuclear power has improved the safety and performance of Nuclear reactor, and has proposed new and safer reactor designs. However, a perfect safety cannot be guaranteed. Potential sources of problems include human errors and external events that have a greater impact than anticipated: the designers of reactors at Fukushima in Japan did not anticipate that a tsunami generated by an earthquake would disable the backup systems which were supposed to stabilize the reactor after the earthquake.Phillip Lipscy, Kenji Kushida, and Trevor Incerti. 2013. " The Fukushima Disaster and Japan's Nuclear Plant Vulnerability in Comparative Perspective ." Environmental Science and Technology 47 (May), 6082–6088. Catastrophic scenarios involving terrorist attacks, war, insider sabotage, and are also conceivable.
Nuclear weapon safety, as well as the safety of Military science involving nuclear materials, is generally handled by agencies different from those that oversee civilian safety, for various reasons, including secrecy.Force V: The history of Britain's airborne deterrent, by Andrew Brookes. Jane's Publishing Co Ltd; First Edition 1 Jan. 1982, , p.101. There are ongoing concerns about terrorist groups acquiring nuclear bomb-making material.
With the exception of thermonuclear weapons and experimental fusion research, all safety issues specific to nuclear power stems from the need to limit the biological uptake of committed dose (ingestion or inhalation of radioactive materials), and external radiation dose due to radioactive contamination.
Nuclear safety therefore covers at minimum:
The IAEA Convention on Nuclear Safety was adopted in Vienna on 17 June 1994 and entered into force on 24 October 1996. The objectives of the convention are to achieve and maintain a high level of nuclear safety worldwide, to establish and maintain effective defences in nuclear installations against potential radiological hazards, and to prevent accidents having radiological consequences. IAEA Convention on Nuclear Safety
The convention was drawn up in the aftermath of the Three Mile Island and Chernobyl accidents at a series of expert level meetings from 1992 to 1994, and was the result of considerable work by States, including their national regulatory and nuclear safety authorities, and the International Atomic Energy Agency, which serves as the Secretariat for the convention.
The obligations of the Contracting Parties are based to a large extent on the application of the safety principles for nuclear installations contained in the IAEA document Safety Fundamentals ‘The Safety of Nuclear Installations’ (IAEA Safety Series No. 110 published 1993). These obligations cover the legislative and regulatory framework, the regulatory body, and technical safety obligations related to, for instance, siting, design, construction, operation, the availability of adequate financial and human resources, the assessment and verification of safety, quality assurance and emergency preparedness.
The convention was amended in 2014 by the Vienna Declaration on Nuclear Safety. This resulted in the following principles:
1. New nuclear power plants are to be designed, sited, and constructed, consistent with the objective of preventing accidents in the commissioning and operation and, should an accident occur, mitigating possible releases of radionuclides causing long-term off site contamination and avoiding early radioactive releases or radioactive releases large enough to require long-term protective measures and actions.
2. Comprehensive and systematic safety assessments are to be carried out periodically and regularly for existing installations throughout their lifetime in order to identify safety improvements that are oriented to meet the above objective. Reasonably practicable or achievable safety improvements are to be implemented in a timely manner.
3. National requirements and regulations for addressing this objective throughout the lifetime of nuclear power plants are to take into account the relevant IAEA Safety Standards and, as appropriate, other good practices as identified inter alia in the Review Meetings of the CNS.
There are several problems with the IAEA, says Najmedin Meshkati of University of Southern California, writing in 2011:
"It recommends safety standards, but member states are not required to comply; it promotes nuclear energy, but it also monitors nuclear use; it is the sole global organization overseeing the nuclear energy industry, yet it is also weighed down by checking compliance with the Nuclear Non-Proliferation Treaty (NPT)".
The book argues that nuclear safety is compromised by the suspicion that, as Eisaku Sato, formerly a governor of Fukushima province (with its infamous nuclear reactor complex), has put it of the regulators: "They're all birds of a feather".
The safety of nuclear plants and materials controlled by the U.S. government for research, weapons production, and those powering naval vessels is not governed by the NRC. About NRC, U.S. Nuclear Regulatory Commission, Retrieved 2007-06-01. Our Governing Legislation, U.S. Nuclear Regulatory Commission, Retrieved 2007-06-01. In the UK nuclear safety is regulated by the Office for Nuclear Regulation (ONR) and the Defence Nuclear Safety Regulator (DNSR). The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) is the Federal Government body that monitors and identifies solar radiation and nuclear radiation risks in Australia. It is the main body dealing with ionizing and non-ionizing radiation Health and Safety http://www.australia.gov.au and publishes material regarding radiation protection. Radiation Protection http://www.arpansa.gov.au
Other agencies include:
The reactors themselves were enormously complex machines with an incalculable number of things that could go wrong. When that happened at Three Mile Island in 1979, another fault line in the nuclear world was exposed. One malfunction led to another, and then to a series of others, until the core of the reactor itself began to melt, and even the world's most highly trained nuclear engineers did not know how to respond. The accident revealed serious deficiencies in a system that was meant to protect public health and safety.Stephanie Cooke (2009). , Black Inc., p. 280.
The 1979 Three Mile Island accident inspired Perrow's book Normal Accidents, where a nuclear accident occurs, resulting from an unanticipated interaction of multiple failures in a complex system. TMI was an example of a normal accident because it was "unexpected, incomprehensible, uncontrollable and unavoidable".Perrow, C. (1982), ‘The President's Commission and the Normal Accident’, in Sils, D., Wolf, C. and Shelanski, V. (Eds), Accident at Three Mile Island: The Human Dimensions, Westview, Boulder, pp.173–184.
Perrow concluded that the failure at Three Mile Island was a consequence of the system's immense complexity. Such modern high-risk systems, he realized, were prone to failures however well they were managed. It was inevitable that they would eventually suffer what he termed a 'normal accident'. Therefore, he suggested, we might do better to contemplate a radical redesign, or if that was not possible, to abandon such technology entirely.
A fundamental issue contributing to a nuclear power system's complexity is its extremely long lifetime. The timeframe from the start of construction of a commercial nuclear power station through the safe disposal of its last radioactive waste, may be 100 to 150 years.
It is impossible for a commercial nuclear reactor to explode like a nuclear bomb since the fuel is never sufficiently enriched for this to occur.Safety of Nuclear Power Reactors, World Nuclear Association, http://www.world-nuclear.org/info/inf06.html
Nuclear reactors can fail in a variety of ways. Should the instability of the nuclear material generate unexpected behavior, it may result in an uncontrolled power excursion. Normally, the cooling system in a reactor is designed to be able to handle the excess heat this causes; however, should the reactor also experience a loss-of-coolant accident, then the fuel may melt or cause the vessel in which it is contained to overheat and melt. This event is called a nuclear meltdown.
After shutting down, for some time the reactor still needs external energy to power its cooling systems. Normally this energy is provided by the power grid to which that plant is connected, or by emergency diesel generators. Failure to provide power for the cooling systems, as happened in Fukushima I, can cause serious accidents.
Nuclear safety rules in the United States "do not adequately weigh the risk of a single event that would knock out electricity from the grid and from emergency generators, as a quake and tsunami recently did in Japan", Nuclear Regulatory Commission officials said in June 2011.
In the U.S., plants are surrounded by a double row of tall fences which are electronically monitored. The plant grounds are patrolled by a sizeable force of armed guards. U.S. NRC: "Nuclear Security – Five Years After 9/11". Accessed 23 July 2007 In Canada, all reactors have an "on-site armed response force" that includes light-armored vehicles that patrol the plants daily. The NRC's "Design Basis Threat" criterion for plants is a secret, and so what size of attacking force the plants are able to protect against is unknown. However, to scram (make an emergency shutdown) a plant takes fewer than 5 seconds while unimpeded restart takes hours, severely hampering a terrorist force in a goal to release radioactivity.
Attack from the air is an issue that has been highlighted since the September 11 attacks in the U.S. However, it was in 1972 when three hijackers took control of a domestic passenger flight along the east coast of the U.S. and threatened to crash the plane into a U.S. nuclear weapons plant in Oak Ridge, Tennessee. The plane got as close as 8,000 feet above the site before the hijackers’ demands were met. Threat Assessment: U.S. Nuclear Plants Near Airports May Be at Risk of Airplane Attack , Global Security Newswire, June 11, 2003.Newtan, Samuel Upton (2007). Nuclear War 1 and Other Major Nuclear Disasters of the 20th Century, AuthorHouse, p.146.
The most important barrier against the release of radioactivity in the event of an aircraft strike on a nuclear power plant is the containment building and its missile shield. Former NRC Chairman Dale Klein has said "Nuclear power plants are inherently robust structures that our studies show provide adequate protection in a hypothetical attack by an airplane. The NRC has also taken actions that require nuclear power plant operators to be able to manage large fires or explosions—no matter what has caused them."
In addition, supporters point to large studies carried out by the U.S. Electric Power Research Institute that tested the robustness of both reactor and waste fuel storage and found that they should be able to sustain a terrorist attack comparable to the September 11 terrorist attacks in the U.S. Spent fuel is usually housed inside the plant's "protected zone" or a spent nuclear fuel shipping cask; stealing it for use in a "dirty bomb" would be extremely difficult. Exposure to the intense radiation would almost certainly quickly incapacitate or kill anyone who attempts to do so.
The danger arising from a terrorist caused large aircraft crash on a nuclear power plant is currently being discussed. Such a terrorist attack could have catastrophic consequences. Terroranschlag auf Atomkraftwerk Biblis würde Berlin bedrohen. In: Der Spiegel For example, the German government has confirmed that the nuclear power plant Biblis A would not be completely protected from an attack by a military aircraft.In: Der Spiegel: Biblis nicht gegen Flugzeugabsturz geschützt Following the terrorist attacks in Brussels in 2016, several nuclear power plants were partially evacuated. At the same time, it became known that the terrorists had spied on the nuclear power plants, and several employees had their access privileges withdrawn. Tihange-Mitarbeiter gesperrt, Terroristen spähen Wissenschaftler aus , Aachener Zeitung, 24.3.2016
Moreover, "nuclear terrorism", for instance with a so-called "Dirty bomb," poses a considerable potential hazard.Wolf-Georg Schärf, Europäisches Atomrecht. Recht der Nuklearenergie Berlin – Boston 2012, S. 1. spiegel.de: Experten warnen vor neuen Terrorgefahren durch Atom-Comeback
The design of plants located in Earthquake active zones also requires the risk of earthquakes and tsunamis to be taken into account. Japan, India, China and the USA are among the countries to have plants in earthquake-prone regions. Damage caused to Japan's Kashiwazaki-Kariwa Nuclear Power Plant during the 2007 Chūetsu offshore earthquakeABC News. Strong Quake Rocks Northwestern Japan . July 16, 2007.Xinhua News. Two die, over 200 injured in strong quake in Japan . July 16, 2007. underlined concerns expressed by experts in Japan prior to the Fukushima accidents, who have warned of a genpatsu-shinsai (domino-effect nuclear power plant earthquake disaster). Genpatsu-Shinsai: Catastrophic Multiple Disaster of Earthquake and Quake-induced Nuclear Accident Anticipated in the Japanese Islands (Abstract), Katsuhiko Ishibashi, 23rd. General Assembly of IUGG, 2003, Sapporo, Japan, accessed 2011-03-28
Safeguarding critical infrastructure like nuclear power plants is a requirement and necessary for chemical facilities, operating nuclear reactors and many other utility facilities. In 2003, the United States Nuclear Regulatory Commission (NRC) developed mandates regarding enhanced security at nuclear power plants. Primary among them were changes to the security perimeter and the screening of employees, vendors, and visitors as they accessed the site. Many facilities recognize their vulnerabilities, and licensed security-contracting firms have arisen.
NRC says, "nuclear power plants sometimes release radioactive gases and liquids into the environment under controlled, monitored conditions to ensure that they pose no danger to the public or the environment", and "routine emissions during normal operation of a nuclear power plant are never lethal".
According to the United Nations (UNSCEAR), regular nuclear power plant operation including the nuclear fuel cycle amounts to 0.0002 sievert (mSv) annually in average public radiation exposure; the legacy of the Chernobyl disaster is 0.002 mSv/a as a global average as of a 2008 report; and natural radiation exposure averages 2.4 mSv annually although frequently varying depending on an individual's location from 1 to 13 mSv.
Japan has been accused by authors such as journalist Yoichi Funabashi of having an "aversion to facing the potential threat of nuclear emergencies." According to him, a national program to develop robots for use in nuclear emergencies was terminated in midstream because it "smacked too much of underlying danger." Though Japan is a major power in robotics, it had none to send in to Fukushima during the disaster. He mentions that Japan's Nuclear Safety Commission stipulated in its safety guidelines for light-water nuclear facilities that "the potential for extended loss of power need not be considered." However, this kind of extended loss of power to the cooling pumps caused the Fukushima meltdown.
In other countries such as the UK, nuclear plants have not been claimed to be absolutely safe. It is instead claimed that a major accident has a likelihood of occurrence lower than (for example) 0.0001/year.
Incidents such as the Fukushima Daiichi nuclear disaster could have been avoided with stricter regulations over nuclear power. In 2002, TEPCO, the company that operated the Fukushima plant, admitted to falsifying reports on over 200 occasions between 1997 and 2002. TEPCO faced no fines for this. Instead, they fired four of their top executives. Three of these four later went on to take jobs at companies that do business with TEPCO.Wang, Qiang, Xi Chen, and Xu Yi-Chong. "Accident like the Fukushima Unlikely in a Country with Effective Nuclear Regulation: Literature Review and Proposed Guidelines." Renewable and Sustainable Energy Reviews 16.1 (2012): 126–46. Web. 3 July 2016.
Appendix C - Licensee Safeguards Contingency Plans
Appendix G - Reserved
Refer to Security Lighting for regulation details affiliated with 10 CFR 73.55(i)(6)(ii), identifying minimum illumination requirements.
Refer to Cybersecurity for regulation details affiliated with 10 CFR 73.54, identifying cybersecurity requirements for nuclear facilities. For guidelines on the satisfaction of 10 CFR 73.54 requirements, refer to .
The difference between short-lived high-level nuclear waste and long-lived low-level waste can be illustrated by the following example. As stated above, one mole of both 131I and 129I release 3x1023 decays in a period equal to one half-life. 131I decays with the release of 970 keV whilst 129I decays with the release of 194 keV of energy. 131gm of 131I would therefore release 45 gigajoules over eight days beginning at an initial rate of 600 EBq releasing 90 kilo with the last radioactive decay occurring inside two years. In contrast, 129gm of 129I would therefore release 9 gigajoules over 15.7 million years beginning at an initial rate of 850 MBq releasing 25 micro with the radioactivity decreasing by less than 1% in 100,000 years.
One tonne of nuclear waste also reduces Carbon dioxide emission by 25 million tonnes.
Radionuclides such as 129I or 131I, may be highly radioactive, or very long-lived, but they cannot be both. One mole of 129I (129 grams) undergoes the same number of decays (3x1023) in 15.7 million years, as does one mole of 131I (131 grams) in 8 days. 131I is therefore highly radioactive, but disappears very quickly, whilst 129I releases a very low level of radiation for a very long time. Two long-lived fission products, technetium-99 (half-life 220,000 years) and iodine-129 (half-life 15.7 million years), are of somewhat greater concern because of a greater chance of entering the biosphere. The transuranic elements in spent fuel are neptunium-237 (half-life two million years) and plutonium-239 (half-life 24,000 years), which will also remain in the environment for long periods of time. A more complete solution to both the problem of both and to the need for low-carbon energy may be the integral fast reactor. One tonne of nuclear waste after a complete burn in an IFR reactor will have prevented 500 million tonnes of Carbon dioxide from entering the atmosphere. Otherwise, waste storage usually necessitates treatment, followed by a long-term management strategy involving permanent storage, disposal or transformation of the waste into a non-toxic form.
Governments around the world are considering a range of waste management and disposal options, usually involving deep-geologic placement, although there has been limited progress toward implementing long-term waste management solutions. This is partly because the timeframes in question when dealing with radioactive waste range from 10,000 to millions of years, according to studies based on the effect of estimated radiation doses.
Since the fraction of a radioisotope's atoms decaying per unit of time is inversely proportional to its half-life, the relative radioactivity of a quantity of buried human radioactive waste would diminish over time compared to natural radioisotopes (such as the decay chain of 120 trillion tons of thorium and 40 trillion tons of uranium which are at relatively trace concentrations of parts per million each over the crust's 3 * 1019 ton mass).American Geophysical Union, Fall Meeting 2007, abstract #V33A-1161. Mass and Composition of the Continental Crust For instance, over a timeframe of thousands of years, after the most active short half-life radioisotopes decayed, burying U.S. nuclear waste would increase the radioactivity in the top 2000 feet of rock and soil in the United States (10 million km2) by ≈ 1 part in 10 million over the cumulative amount of natural radioisotopes in such a volume, although the vicinity of the site would have a far higher concentration of artificial radioisotopes underground than such an average.Interdisciplinary Science Reviews 23:193–203;1998. Dr. Bernard L. Cohen, University of Pittsburgh. Perspectives on the High Level Waste Disposal Problem
At the same time, there is some evidence that operational practices are not easy to change. Operators almost never follow instructions and written procedures exactly, and “the violation of rules appears to be quite rational, given the actual workload and timing constraints under which the operators must do their job”. Many attempts to improve nuclear safety culture “were compensated by people adapting to the change in an unpredicted way”.
According to Areva's Southeast Asia and Oceania director, Selena Ng, Japan's Fukushima nuclear disaster is "a huge wake-up call for a nuclear industry that hasn't always been sufficiently transparent about safety issues". She said "There was a sort of complacency before Fukushima and I don't think we can afford to have that complacency now".
An assessment conducted by the Commissariat à l’Énergie Atomique (CEA) in France concluded that no amount of technical innovation can eliminate the risk of human-induced errors associated with the operation of nuclear power plants. Two types of mistakes were deemed most serious: errors committed during field operations, such as maintenance and testing, that can cause an accident; and human errors made during small accidents that cascade to complete failure.
According to Mycle Schneider, reactor safety depends above all on a 'culture of security', including the quality of maintenance and training, the competence of the operator and the workforce, and the rigour of regulatory oversight. So a better-designed, newer reactor is not always a safer one, and older reactors are not necessarily more dangerous than newer ones. The 1979 Three Mile Island accident in the United States occurred in a reactor that had started operation only three months earlier, and the Chernobyl disaster occurred after only two years of operation. A serious loss of coolant occurred at the French Civaux-1 reactor in 1998, less than five months after start-up.
However safe a plant is designed to be, it is operated by humans who are prone to errors. Laurent Stricker, a nuclear engineer and chairman of the World Association of Nuclear Operators says that operators must guard against complacency and avoid overconfidence. Experts say that the "largest single internal factor determining the safety of a plant is the culture of security among regulators, operators and the workforce — and creating such a culture is not easy".
Investigative journalist Eric Schlosser, author of Command and Control, discovered that at least 700 "significant" accidents and incidents involving 1,250 were recorded in the United States between 1950 and 1968. Experts believe that up to 50 nuclear weapons were lost during the Cold War.
172,000 people living within a 30 kilometre radius of the Fukushima Daiichi nuclear power plant, have been forced or advised to evacuate the area. More generally, a 2011 analysis by Nature and Columbia University, New York, shows that some 21 nuclear plants have populations larger than 1 million within a 30-km radius, and six plants have populations larger than 3 million within that radius.
Black Swan events are highly unlikely occurrences that have big repercussions. Despite planning, nuclear power will always be vulnerable to black swan events:
The AP1000 has an estimated core damage frequency of 5.09 × 10−7 per plant per year. The Evolutionary Power Reactor (EPR) has an estimated core damage frequency of 4 × 10−7 per plant per year. In 2006 General Electric published recalculated estimated core damage frequencies per year per plant for its nuclear power plant designs:
Kennette Benedict has said that nuclear technology and plant operations continue to lack transparency and to be relatively closed to public view:
In 1986, Soviet officials held off reporting the Chernobyl disaster for several days. The operators of the Fukushima plant, Tokyo Electric Power Co, were also criticised for not quickly disclosing information on releases of radioactivity from the plant. Russian President Dmitry Medvedev said there must be greater transparency in nuclear emergencies.
Historically many scientists and engineers have made decisions on behalf of potentially affected populations about whether a particular level of risk and uncertainty is acceptable for them. Many nuclear engineers and scientists that have made such decisions, even for good reasons relating to long term energy availability, now consider that doing so without informed consent is wrong, and that nuclear power safety and nuclear technologies should be based fundamentally on morality, rather than purely on technical, economic and business considerations.Pandora's box, A is for Atom- Adam Curtis
Non-Nuclear Futures: The Case for an Ethical Energy Strategy is a 1975 book by Amory B. Lovins and John H. Price.Lovins, Amory B. and Price, John H. (1975). Non-nuclear Futures: The Case for an Ethical Energy Strategy (Cambridge, Mass.: Ballinger Publishing Company, 1975. xxxii + 223pp. , ). The main theme of the book is that the most important parts of the nuclear power debate are not technical disputes but relate to personal values, and are the legitimate province of every citizen, whether technically trained or not. Non-Nuclear Futures, pp. xix–xxi. The authors believed that nuclear reactors were less reliable (a grossly incorrect prediction) and take longer to build, exposing them to escalated interest costs, mistimed demand forecasts, and wage pressure by unions.
Whatever position one takes in the nuclear power debate, the possibility of catastrophic accidents and consequent economic costs must be considered when nuclear policy and regulations are being framed.
UNSCEAR has conducted 20 years of detailed scientific and epidemiological research on the effects of the Chernobyl accident. Apart from the 57 direct deaths in the accident itself, UNSCEAR predicted in 2005 that up to 4,000 additional cancer deaths related to the accident would appear "among the 600 000 persons receiving more significant exposures (liquidators working in 1986–87, evacuees, and residents of the most contaminated areas)". Russia, Ukraine, and Belarus have been burdened with the continuing and substantial decontamination and health care costs of the Chernobyl disaster.
Eleven of Russia's reactors are of the RBMK 1000 type, similar to the one at Chernobyl Nuclear Power Plant. Some of these RBMK reactors were originally to be shut down but have instead been given life extensions and uprated in output by about 5%. Critics say that these reactors are of an "inherently unsafe design", which cannot be improved through upgrades and modernization, and some reactor parts are impossible to replace. Russian environmental groups say that the lifetime extensions "violate Russian law, because the projects have not undergone environmental assessments".
A 2012 report in The Economist said: "The reactors at Fukushima were of an old design. The risks they faced had not been well analysed. The operating company was poorly regulated and did not know what was going on. The operators made mistakes. The representatives of the safety inspectorate fled. Some of the equipment failed. The establishment repeatedly played down the risks and suppressed information about the movement of the radioactive plume, so some people were evacuated from more lightly to more heavily contaminated places".
The designers of the Fukushima I Nuclear Power Plant reactors did not anticipate that a tsunami generated by an earthquake would disable the backup systems that were supposed to stabilize the reactor after the earthquake. Nuclear reactors are such "inherently complex, tightly coupled systems that, in rare, emergency situations, cascading interactions will unfold very rapidly in such a way that human operators will be unable to predict and master them".
According to the International Atomic Energy Agency, Japan "underestimated the danger of tsunamis and failed to prepare adequate backup systems at the Fukushima Daiichi nuclear plant". This repeated a widely held criticism in Japan that "collusive ties between regulators and industry led to weak oversight and a failure to ensure adequate safety levels at the plant". The IAEA also said that the Fukushima disaster exposed the lack of adequate backup systems at the plant. Once power was completely lost, critical functions like the cooling system shut down. Three of the reactors "quickly overheated, causing meltdowns that eventually led to explosions, which hurled large amounts of radioactive material into the air".
Louise Fréchette and Trevor Findlay have said that more effort is needed to ensure nuclear safety and improve responses to accidents:
David Lochbaum, chief nuclear safety officer with the Union of Concerned Scientists, has repeatedly questioned the safety of the Fukushima I Plant's General Electric Mark 1 reactor design, which is used in almost a quarter of the United States' nuclear fleet.
A report from the Japanese Government to the IAEA says the "nuclear fuel in three reactors probably melted through the inner containment vessels, not just the core". The report says the "inadequate" basic reactor design — the Mark-1 model developed by General Electric — included "the venting system for the containment vessels and the location of spent fuel cooling pools high in the buildings, which resulted in leaks of radioactive water that hampered repair work".
Following the Fukushima emergency, the European Union decided that reactors across all 27 member nations should undergo safety tests.
According to UBS AG, the Fukushima I nuclear accidents are likely to hurt the nuclear power industry's credibility more than the Chernobyl disaster in 1986:
The Fukushima accident exposed some troubling nuclear safety issues:
As of January 2012, questions also linger as to the extent of damage to the Fukushima plant caused by the earthquake even before the tsunami hit. Any evidence of serious quake damage at the plant would "cast new doubt on the safety of other reactors in quake-prone Japan".
Two government advisers have said that "Japan's safety review of nuclear reactors after the Fukushima disaster is based on faulty criteria and many people involved have conflicts of interest". Hiromitsu Ino, Professor Emeritus at the University of Tokyo, says
"The whole process being undertaken is exactly the same as that used previous to the Fukushima Dai-Ichi accident, even though the accident showed all these guidelines and categories to be insufficient".
In March 2012, Prime Minister Yoshihiko Noda acknowledged that the Japanese government shared the blame for the Fukushima disaster, saying that officials had been blinded by a false belief in the country's "technological infallibility", and were all too steeped in a "safety myth".
In spite of accidents like these, studies have shown that nuclear deaths are mostly in uranium mining and that nuclear energy has generated far fewer deaths than the high pollution levels that result from the use of conventional fossil fuels. However, the nuclear power industry relies on uranium mining, which itself is a hazardous industry, with many accidents and fatalities.
Journalist Stephanie Cooke says that it is not useful to make comparisons just in terms of number of deaths, as the way people live afterwards is also relevant, as in the case of the 2011 Japanese nuclear accidents:
The Fukushima accident forced more than 80,000 residents to evacuate from neighborhoods around the plant.
A survey by the Iitate, Fukushima local government obtained responses from some 1,743 people who have evacuated from the village, which lies within the emergency evacuation zone around the crippled Fukushima Daiichi Plant. It shows that many residents are experiencing growing frustration and instability due to the nuclear crisis and an inability to return to the lives they were living before the disaster. Sixty percent of respondents stated that their health and the health of their families had deteriorated after evacuating, while 39.9 percent reported feeling more irritated compared to before the disaster.
Chemical components of the radioactive waste may lead to cancer.
For example, Iodine 131 was released along with the radioactive waste when Chernobyl disaster and Fukushima disasters occurred. It was concentrated in leafy vegetation after absorption in the soil. It also stays in animals’ milk if the animals eat the vegetation. When Iodine 131 enters the human body, it migrates to the thyroid gland in the neck and can cause thyroid cancer.
Other elements from nuclear waste can lead to cancer as well. For example, Strontium 90 causes breast cancer and leukemia, Plutonium 239 causes liver cancer.
Newer reactor designs intended to provide increased safety have been developed over time. These designs include those that incorporate passive safety and Small Modular Reactors. While these reactor designs "are intended to inspire trust, they may have an unintended effect: creating distrust of older reactors that lack the touted safety features".
The next nuclear plants to be built will likely be Generation III or III+ designs, and a few such are already in operation in Japan. Generation IV reactors would have even greater improvements in safety. These new designs are expected to be passively safe or nearly so, and perhaps even inherently safe (as in the PBMR designs).
Some improvements made (not all in all designs) are having three sets of emergency diesel generators and associated emergency core cooling systems rather than just one pair, having quench tanks (large coolant-filled tanks) above the core that open into it automatically, having a double containment (one containment building inside another), etc.
Approximately 120 reactors, NRC pdf on generations of FCVSs such as all those in Switzerland prior to and all reactors in Japan after the Fukushima accident, incorporate Filtered Containment Venting Systems, onto the containment structure, which are designed to relieve the containment pressure during an accident by releasing gases to the environment while retaining most of the fission products in the filter structures.
However, safety risks may be the greatest when nuclear systems are the newest, and operators have less experience with them. Nuclear engineer David Lochbaum explained that almost all serious nuclear accidents occurred with what was at the time the most recent technology. He argues that "the problem with new reactors and accidents is twofold: scenarios arise that are impossible to plan for in simulations; and humans make mistakes". As one director of a U.S. research laboratory put it, "fabrication, construction, operation, and maintenance of new reactors will face a steep learning curve: advanced technologies will have a heightened risk of accidents and mistakes. The technology may be proven, but people are not".Benjamin K. Sovacool. A Critical Evaluation of Nuclear Power and Renewable Electricity in Asia, Journal of Contemporary Asia, Vol. 40, No. 3, August 2010, p. 381.
Precipitated by a 2010 Nuclear Security Summit convened by the Obama administration, China and the United States launched a number of initiatives to secure potentially dangerous, Chinese-supplied, nuclear material in countries such as Ghana or Nigeria. Through these initiatives, China and the US have converted Chinese-origin Miniature Neutron Source Reactors (MNSRs) from using highly enriched uranium to using low-enriched uranium fuel (which is not directly usable in weapons, thereby making reactors more proliferation resistant).
China and the United States collaborated to build the China Center of Excellence on Nuclear Security, which opened in 2015. The Center is a forum for nuclear security exchange, training, and demonstration in the Asia Pacific region.
The United States 9/11 Commission has said that nuclear power plants were potential targets originally considered for the September 11, 2001 attacks. If terrorist groups could sufficiently damage safety systems to cause a core meltdown at a nuclear power plant, and/or sufficiently damage spent fuel pools, such an attack could lead to widespread radioactive contamination. The Federation of American Scientists have said that if nuclear power use is to expand significantly, nuclear facilities will have to be made extremely safe from attacks that could release massive quantities of radioactivity into the community. New reactor designs have features of passive safety, which may help. In the United States, the NRC carries out "Force on Force" (FOF) exercises at all Nuclear Power Plant (NPP) sites at least once every three years.
become preferred targets during military conflict and, over the past three decades, have been repeatedly attacked during military air strikes, occupations, invasions and campaigns. Various acts of civil disobedience since 1980 by the peace group Plowshares have shown how nuclear weapons facilities can be penetrated, and the groups actions represent extraordinary breaches of security at nuclear weapons plants in the United States. The National Nuclear Security Administration has acknowledged the seriousness of the 2012 Plowshares action. Non-proliferation policy experts have questioned "the use of private contractors to provide security at facilities that manufacture and store the government's most dangerous military material". materials on the black market are a global concern,Jay Davis. After A Nuclear 9/11 The Washington Post, March 25, 2008.Brian Michael Jenkins. A Nuclear 9/11? CNN.com, September 11, 2008. and there is concern about the possible detonation of a small, crude nuclear weapon by a terrorist group in a major city, with significant loss of life and property.Orde Kittrie. Averting Catastrophe: Why the Nuclear Non-proliferation Treaty is Losing its Deterrence Capacity and How to Restore It May 22, 2007, p. 338.Nicholas D. Kristof. A Nuclear 9/11 The New York Times, March 10, 2004. Stuxnet is a computer worm discovered in June 2010 that is believed to have been created by the United States and Israel to attack Iran's nuclear facilities.
Construction of the International Thermonuclear Experimental Reactor facility began in 2007, but the project has run into many delays and cost overrun. The facility is now not expected to begin operations until the year 2027 – 11 years after initially anticipated. A follow on commercial nuclear fusion power station, DEMO, has been proposed. – Projected fusion power timeline There is also suggestions for a power plant based upon a different fusion approach, that of an Inertial fusion power plant.
Fusion powered electricity generation was initially believed to be readily achievable, as fission power had been. However, the extreme requirements for continuous reactions and plasma containment led to projections being extended by several decades. In 2010, more than 60 years after the first attempts, commercial power production was still believed to be unlikely before 2050.
Coastal nuclear sites must also be further protected against rising sea levels, storm surges, flooding, and possible eventual "nuclear site islanding".
Failure modes of nuclear power plants
Operating nuclear reactors contain large amounts of radioactive fission products which, if dispersed, can pose a direct radiation hazard, contaminate soil and vegetation, and be ingested by humans and animals. Human exposure at high enough levels can cause both short-term illness and death and longer-term death by cancer and other diseases. Globalsecurity.org: Nuclear Power Plants: Vulnerability to Terrorist Attack p. 3.
Vulnerability of nuclear plants to attack
Threat of terrorist attacks
Plant location
Multiple reactors
Nuclear safety systems
Routine emissions of radioactive materials
Japanese public perception of nuclear power safety
Uranium supplies
Title 10 CFR Part 73 (U.S. NRC)
+ Table ( 10 CFR Part 73 - Physical Protection of Plants and Materials)
! Subpart
!Sections A - General Provisions § 73.1 - 73.8 B - Enhanced Weapons, Preemption, and Firearms Background Checks § 73.15, § 73.17 C - General Performance Objective for Protection of Strategic Special Nuclear Material § 73.20 D - Protection of Safeguards Information § 73.21 - 73.23 E - Physical Protection Requirements of Special Nuclear Material and Spent Nuclear Fuel in Transit § 73.24 - 73.38 F - Physical Protection Requirements at Fixed Sites § 73.40 - 73.55 G - Access Authorization and Access Control Requirements for the Physical Protection of Special Nuclear Material § 73.56 - 73.67 H - Records and Postings § 73.70 – 73.75 I - Enforcement § 73.77 – 73.81 Subpart J - Subpart S Reserved T - Security Notifications, Reports, and Recordkeeping § 73.1200 – 73.1215 Appendix A - U.S. Nuclear Regulatory Commission Offices and Classified Mailing Addresses
Appendix B - General Criteria for Security Personnel
Other
Hazards of nuclear material
Safety culture and human errors
Risks
The extreme danger of the radioactive material in power plants and of nuclear technology in and of itself is so well known that the US government was prompted (at the industry's urging) to enact provisions that protect the nuclear industry from bearing the full burden of such inherently risky nuclear operations. The Price-Anderson Act limits industry's liability in the case of accidents, and the 1982 Nuclear Waste Policy Act charges the federal government with responsibility for permanently storing nuclear waste.
Population density is one critical lens through which other risks have to be assessed, says Laurent Stricker, a nuclear engineer and chairman of the World Association of Nuclear Operators:
The KANUPP plant in Karachi, Pakistan, has the most people — 8.2 million — living within 30 kilometres of a nuclear plant, although it has just one relatively small reactor with an output of 125 megawatts. Next in the league, however, are much larger plants — Taiwan's 1,933-megawatt Kuosheng plant with 5.5 million people within a 30-kilometre radius and the 1,208-megawatt Chin Shan plant with 4.7 million; both zones include the capital city of Taipei.
A rare event – especially one that has never occurred – is difficult to foresee, expensive to plan for and easy to discount with statistics. Just because something is only supposed to happen every 10,000 years does not mean that it will not happen tomorrow. Over the typical 40-year life of a plant, assumptions can also change, as they did on September 11, 2001, in August 2005 when Hurricane Katrina struck, and in March, 2011, after Fukushima.
The list of potential black swan events is "damningly diverse":
Nuclear reactors and their spent-fuel pools could be targets for terrorists piloting hijacked planes. Reactors may be situated downstream from dams that, should they ever burst, could unleash massive floods. Some reactors are located close to faults or shorelines, a dangerous scenario like that which emerged at Three Mile Island and Fukushima – a catastrophic coolant failure, the overheating and melting of the radioactive fuel rods, and a release of radioactive material.
Beyond design basis events
Transparency and ethics
Despite victories like the creation of the Atomic Energy Commission, and later the Nuclear Regular Commission, the secrecy that began with the Manhattan Project has tended to permeate the civilian nuclear program, as well as the military and defense programs.
Nuclear and radiation accidents
Accident liability protection
Hanford Site
1986 Chernobyl disaster
2011 Fukushima I accidents
Lacking electricity to pump water needed to cool the atomic core, engineers vented radioactive steam into the atmosphere to release pressure, leading to a series of explosions that blew out concrete walls around the reactors. Radiation readings spiked around Fukushima as the disaster widened, forcing the evacuation of 200,000 people. There was a rise in radiation levels on the outskirts of Tokyo, with a population of 30 million, 135 miles (210 kilometers) to the south.
Back-up diesel generators that might have averted the disaster were positioned in a basement, where they were quickly overwhelmed by waves. The cascade of events at Fukushima had been predicted in a report published in the U.S. several decades ago:
The 1990 report by the U.S. Nuclear Regulatory Commission, an independent agency responsible for safety at the country's power plants, identified earthquake-induced diesel generator failure and power outage leading to failure of cooling systems as one of the “most likely causes” of nuclear accidents from an external event.
The report was cited in a 2004 statement by Japan's Nuclear and Industrial Safety Agency, but it seems adequate measures to address the risk were not taken by TEPCO. Katsuhiko Ishibashi, a seismology professor at Kobe University, has said that Japan's history of nuclear accidents stems from an overconfidence in plant engineering. In 2006, he resigned from a government panel on nuclear reactor safety, because the review process was rigged and “unscientific”.
The multiple reactor crises at Japan's Fukushima nuclear power plant reinforce the need for strengthening global instruments to ensure nuclear safety worldwide. The fact that a country that has been operating nuclear power reactors for decades should prove so alarmingly improvisational in its response and so unwilling to reveal the facts even to its own people, much less the International Atomic Energy Agency, is a reminder that nuclear safety is a constant work-in-progress.
The accident in the former Soviet Union 25 years ago 'affected one reactor in a totalitarian state with no safety culture,' UBS analysts including Per Lekander and Stephen Oldfield wrote in a report today. 'At Fukushima, four reactors have been out of control for weeks – casting doubt on whether even an advanced economy can master nuclear safety.'
Despite the resources poured into analyzing crustal movements and having expert committees determine earthquake risk, for instance, researchers never considered the possibility of a magnitude-9 earthquake followed by a massive tsunami. The failure of multiple safety features on nuclear power plants has raised questions about the nation's engineering prowess. Government flip-flopping on acceptable levels of radiation exposure confused the public, and health professionals provided little guidance. Facing a dearth of reliable information on radiation levels, citizens armed themselves with dosimeters, pooled data, and together produced radiological contamination maps far more detailed than anything the government or official scientific sources ever provided.
Other accidents
Health impacts
"You have people in Japan right now that are facing either not returning to their homes forever, or if they do return to their homes, living in a contaminated area for basically ever... It affects millions of people, it affects our land, it affects our atmosphere ... it's affecting future generations ... I don't think any of these great big massive plants that spew pollution into the air are good. But I don't think it's really helpful to make these comparisons just in terms of number of deaths".
"Summarizing all responses to questions related to evacuees' current family status, one-third of all surveyed families live apart from their children, while 50.1 percent live away from other family members (including elderly parents) with whom they lived before the disaster. The survey also showed that 34.7 percent of the evacuees have suffered salary cuts of 50 percent or more since the outbreak of the nuclear disaster. A total of 36.8 percent reported a lack of sleep, while 17.9 percent reported smoking or drinking more than before they evacuated."
Improvements to nuclear fission technologies
Developing countries
Nuclear security and terrorist attacks
Nuclear fusion research
More stringent safety standards
See also
External links
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