Hetal D. Patel

Ise 370L - Spring '96

hpatel@chaph.usc.edu

What Have We Learned From Three-Mile Island After 17 Years ?

(Implications for Future Chernobyl's )

Today in our energy hungry world, the reliance on nuclear power is getting larger and larger. Nuclear power is on top of the list of forms of power available to generate electricities in the quantities, forms and reliability needed as we head towards the 21st century.Current operating nuclear plants number approximately 430 through out 26 countries (1).

Nuclear energy production will grow an average of 3.3 to 4.2% PER YEAR worldwide from 1988-2005 (IAEA News briefs, Sept.1989). Though we have experienced if not the worst technogenic environmental disaster of the 20th century ten years ago - Chernobyl, together with the partial meltdown at Three Mile Island seventeen years ago, most people today give only passing thoughts to the issue of nuclear safety worldwide.These two cases are only mere examples of the ominous potential for accidents of great magnitude within such nuclear plants worldwide (2). It is vital that we understand both the logic and outcomes of such disasters. Today 10 years later,effects of Chernobyl are still hazardous and have been detected all over the world. Belarus, a country most affected by history's worst nuclear disaster does not even have a nuclear plant. The radiation released from Chernobyl was 200 times more than that of the combined releases of the atom bombs that annihilated Hiroshima and Nagasaki in 1945 (3). Due to prevailing winds, 25 percent of the land in Belarus is uninhabitable. All normal life has stopped there, people are afraid to move, stay, marry and afraid to have families. The costs of the accidents after-effects are monumental; resettlement of people affected, medical and clean-up costs are just a few on the priority list.

The problem lies in ignorance of interactions between human, engineering, organizational and managerial factors of such a system. In most cases human error is customarily cited as a major cause of the calamity. Sometimes in my mind I cannot blame the opearators involved. Reason being that the control rooms of such plants are a maze of complex displays and controls spread over an array of immense rooms. In the case of an emergency, due to the mere size and complexity of such rooms, errors are just begging to occur! Error is also a combination of many factors such as ineffective training, intricate operating procedures, erratic rebuttal systems, non-pliable managerial systems, non-conforming organizational designs and natural disasters. Usually the direction taken to ensure safety at such nuclear plants is one of tending to find an engineering solution. If the above mentioned factors together with the use of safety and human factors in the enginnering education for such large-scale techological systems are used, then we would be heading the right direction; a safer, productive life not only for us but for our environment too. Nuclear regulation is the public's business (4).

Politics, resource and structural problems are another major cause. For example here is the US, the Nuclear Regulatory Commission (NRC) was set up as the major regulatory agency. Under staffed and under skilled employees are just one of their obstacles. Relying on the fact that the industry itself is responsible for safety tests on plants, the NRC has over looked many issues while tending to focus on matters with greatest safety importance. We should all know that system failures can be traced to all those small components that make up this human/machine interface. Whenever we have such components fitted together and are in interaction it is crucial to give weight not only to the human and technological factors but also to how they operate together. The NRC's relationship with the industry has been suspect since its creation in 1974 (5). Operations of such regulatory agencies worldwide is greatly influenced by the member states (IAEA) who have such nuclear operating plants. The power of money in hand and foreign relation policies of these states control the acts and decisions of such agencies. Structural troubles include the fact that it is only optional for member states to comply with or use safety principles set by the International Atomic Energy Agency (IAEA) in 1986 (6). Thus there is no clear cut accord by IAEA member states on the issue of complying with safety standards.

Lack of Safety Culture is yet another obstacle. Many nuclear plants in Central and Eastern Europe (e.g. Ukraine) are just time bombs waiting to blow. Many of these plants have not yet collapsed probably due the fact that combination of events needed for failure has not yet occured or that they have just not been given enough time. Hence it is high time that the international community and the G-7 get involved. The problem(s) in this industry needs to be tackled collectively, no one is in a position today to solve this complex field of science and practice individually, irrespective of depth of education or dedication. Political, economic and cultural barriers have to be crushed if we are to achieve this. A collaborative effort worldwide, especially from the West is needed to form, support a reaserch team, to counter and unravel studies, develop universal policies and to staff such nuclear plants if we are to avoid any more Chernobyl's in the future!

Future Chernobyl's can be avoided but it is upto us. Firstly we must make space for reality to take precedence over public relations for any successful technology, as we cannot fool nature (7). Secondly much greater guarantees, co-operation and communication is needed between the industry, the regulatory agencies and the member states. Safety will only be achieved if ALL those involved play their part whole heartedly and honestly right down from the plant workers through the manufacturers and regulatory agencies right upto the financial institutions that control this whole industry.

References :

1. Los Angeles Herald Examiner, March 28, 1989. N. Meshkati.

2. Los Angeles Herald Examiner, March 28, 1989. N. Meshkati.

3. New York Times, March 31, 1996. M. Specter

4. Time Magazine, March 4, 1996. E. Pooley

5. Time Magazine, March 4, 1996. E. Pooley

6. Foreign Policy Journal; U.N. 50th Anniversary, "The Critical Role of The U.N.in Ensuring the Safety of Nuclear Power Plants Around The World". N.Meshkati.

7. Los Angeles Herald Examiner, March 28, 1989. N. Meshkati. Quote from the late Nobel Physicist; R. Feynman

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Brian Ai Chang

ISE

370L

aichang@scf.usc.edu

1996

WHAT HAVE WE LEARNED FROM TMI 17 YEARS LATER?

(IMPLICATIONS FOR FUTURE CHERNOBYL)

Throughout the many technological advances, none have been more significant than the ability to harness the power of the atom. Many people believed this would be the energy of the future which would make the United States more energy self-sufficient and less dependent on imported oil. Nuclear power provides 20% of the electricity consumed in the U.S.; New England depends on nuclear plants for more than half its supply (Pooley, 1996). With the emphasis shift to provide a cheap, environmental friendly, and safe energy source by the American public, nuclear power companies often sacrifice environment and safety concerns to make the short-term profit. Judging by the Three Mile Island and Chernobyl nuclear power accidents, we have learned nothing to prevent future accidents from happening again.

According to George Betancourt and George Galatis, senior engineers at Northeast Utilities, there have been major problems at Millstone Unit 1, a nuclear power plant in Waterford, Connecticut (Pooley, 1996). Problems such as improper removal of fuel rods, missing data reports, and improper storage of spent fuel are among a few to name. Time and time again, memos were sent to management to addressing serious problems which could lead to catastrophic results similar to or worse than that of the Chernobyl accident. Unfortunately, managements response was to sit on the issue as it would cost money to address the needs of the plant. Managements top priority is to keep the plant on-line to make money while safety and environmental issues are ignored.

In addition, whistleblowers face an even bigger obstacle from management. Performance reports have dropped, and whistleblowers have been sent to mandatory counselings and psychological therapies. Undue harassment is the punishment for trying to fix these problems which in the long run will save money and lives.

The Nuclear Regulatory Commission has not done enough to ensure the safety of the nuclear power plants. The NRC is too connected to the industry that it fails to uphold and regulate the rules established for a safe nuclear power plant. For instance, George Galatis petitioned to deny Northeast Utilities amendment to off-load a full core. The NRC ignored George Galatis petition and granted the amendment though conditions were unsafe. However, Inspector General Nortron conducted an investigation which backed George Galatis claims. The NRCs response was that the organization were aware of the practice but somehow did not realize that this was a violation (Pooley, 1996). Even NRC Chairwoman Shirley Ann Jackson said, The ball got dropped. This is an outrage that professionals do not have the integrity to enforce rules set forth. The main purpose of the NRC is to not drop the ball so that the American public can be assured that nuclear power plants are safe.

What happens when the ball is dropped again will be another Chernobyl accident. The radiation released after the explosion at the reactors core on April 26, 1986, was nearly 200 times that of the combined releases from the atomic bombs at Hiroshima and Nagasaki (Specter, 1996). Instead of a foreign nuclear accident, there will be a complete meltdown devastating the United States. As if the Three Mile Island nuclear accident was not enough, a bigger and worse accident will happen if changes are not made. At the Chernobyl accident, well over 260,000 square kilometers of territory in Ukraine, Russia and Belarus still have more than one curie per square kilometer of contamination with cesium 137 (Shcherbak, 1996). A contamination of this size in the United States will wipe out much land needed for agriculture, housing, and industry. The United States will be crippled economically and medically as the radiation from the nuclear power plants will maim and kill generations of people.

Though the world has experienced two major nuclear accidents at Three Mile Island and Chernobyl, industry, governments, and the people have not learned the severity of those mistakes. There already has been enough lessons. However, these lessons are not being learned. Safety is not adhered to by big business, and therefore, safety will never be an issue until another accident occurs. According to Dr. Najmedin Meshkati, by continuing to be complacent about the operation of large scale hazardous technological systems, by ignoring occasional warning and accident precursors and by avoiding an internationally united and holistic approach to the design and operation of nuclear plants, the horrors of such accidents as Three Mile Island probably will be relived.

BIBLIOGRAPHY

Pooley, Eric. (1996). Safety is not the first at the NRC. Time 46-54

Meshkati, Najmedin. (1989). Are we safer after Three Mile Island? Los Angeles Herald Examiner. A17

Shcherbak, Yuri M. (1996). Ten years of the Chernobyl era. Scientific American. 44-49

Specter, Michael. (March 16,1996). 10 years later, through fear, Chernobyl still kills in Belarus. The New York Times. 1, 4-5.

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What have we Learned after 17 Years From TMI and 10 Years from Chernobyl Accidents: Implications for future Chernobyls

Kevin Hu

khu@scf.usc.edu

ISE 370 spring 1996

Seventeen years following TMI, the first major accident in the history of commercial nuclear energy in the US, only ten years since the globally appalled Chernobyl nuclear reactor explosion in the former Soviet Union, our increasing reliance on nuclear power to generate electricity has made nuclear energy one of the most important source of electricity today. According to the figures disclosed by the Nuclear Energy Institute, "More than 30 nations today rely on nuclear energy for a portion of their electricity supply.", "In 1994, the 432 nuclear power plants operating in the world generated more than 2,000 billion kilowatt-hours of electricity, or about one-sixth of the total electricity produced on the planet." While the nuclear industries worldwide continue to grow for years after the accidents, it is through the shadows of the TMI and Chernobyl's lingering impact that one must address the safety issues on the nuclear power plants around the world.

In spite of the claims by the nuclear industry that "equipment failure, human error and severely flawed reactor design" being the causes of the two catastrophes, the lack of human factors design considerations on both micro and macro-ergonomic levels to ensure the safety of such large-scale technological system was perhaps the heart of the problem.

What was ignored has been quoted that "how the interactions of human, organizational and managerial factors also determine and affect the safety of such system" ( Are we safer after Three Mile Island? LA Herald Examiner, March 28,1989. A17). The deficit in safety culture from the TMI accident in which the lack of effective training, non-responsive managerial system, non-adaptive organizational designs may be reflected upon the findings of the Chernobyl accident by International Atomic Energy Agency's (IAEA) International Nuclear Safety Advisory Group (INSAG), of which "a deficit in safety culture was inherent not only to the state of operation, but also and to no lesser extent to activities at other stages in the lifetime of nuclear power plants (including design, engineering, construction, manufacture and regulation)." (INSAG-7,1992, p.24)

Based on the TMI experience, it is now widely understood that the fundamentals to insure a successful safety program for nuclear energy must be based upon the acknowledgment, commitment and dedication to ensure the safety of nuclear power plants in terms of the micro and macro-environmental factors across the nuclear industries (operating companies), equipment/facility manufacturers and the regulators (independent government monitoring agency). For such program to achieve its purpose, the three components within the infrastructure must maintain continuous information sharing, interaction, improvement, implementation and evaluation on safety issues and standards.

Although years following the TMI incident both the US government and the US nuclear seem to have addressed some of the Human factors issues with a series of maneuvers in reorganization and reorientation of nuclear utilities to focus on safety, the overall effectiveness of the regulatory measures, enforcement, and implementations as well as the promotion of safety culture may still be questionable today.

It was only until a recent investigation of the Time magazine and some articles published in the New York Times which stirred some bubbles to the surface did the American public discover some shocking truth to a series of nuclear safety violations across the industry. Apparently the Nuclear Regulatory Commission, likes its originator- the old Atomic Energy Commission, still functions under some perceptible pressure of the nuclear industry. The nuclear industry vetoes commission nominees it deems too hostile, and agency official enjoy a revolving door to good jobs at nuclear companies such as Northeast. At times the organizational goal of NRC which "to ensure adequate protection of the public health and safety, the common defense and security, and the environment in the use of nuclear materials in the United States" may be put off sight when safety issues conflicts with personal interests. In such cases the effectiveness and integrity of the agency can have such drastic effect on the safety of the public. The articles Blowing the whistle on nuclear safety (Time, March 4 , 1996) exposed the failure of NRC to enforce its own rules regarding the "enforcement discretion" by which it allowed the violation of safety regulation by Northeast utilities' Millstone nuclear plant and many other nuclear plants in sidestepping the safety requirements to go unpunished (Over loading the spend-fuel pool capacity with used fuel rods and cutting down on cool-down period before a full off-load). By turning a blind eye the NRC's manners of which it handled safety issues has been criticized as "the fox guarding the hen house." On top of the many serious safety hazards in nuclear plant operations, other investigations also reported that the management of some plants have abused the practice of certain safety precautions on its workers as a way to punish/intimidate those who raise concerns over safety issues. While the increasing rate slashing competitions within the energy industry may have lead to many commercial nuclear plants to short cut or completely ignore the proper safety procedures in order to reduce cost of operation and maintenance, the total lack of recognition to the significance of safety precautions by the industry together with the inability of NRC to oversee the safety in plants' operations should flash red light to the public on nuclear safety.

As mentioned earlier, the safety environment of the nuclear power plants suffers whenever one or more components within the structure performs poorly or fails to maintain its balance with the system. The role of the regulator such as one that NRC plays- not only as the guard dog, but also a coordinator, a safety catalyst and an advisor for the nuclear industry and the manufactures, is crucial to safeness of nuclear energy on the people. In any case the regulatory agencies must exercise the power in setting high safety standards, prevention of safety hazards through the promotion of safety culture, monitoring plant operations and overseeing safety issues, and strict enforcement of laws and regulations to stop and to punish violation as well as bringing forth improvements. In addition they must also be independent from industry influence and hold integrity in administering policies.

Unless we have both a safety- conscientious industry and an effective regulator, the safeness of our nuclear industry will eventually be tested and revealed either by a normal accident or by any operation error of significant scale. In the event of such failure, the outcome under the lack of safety precautions within the system may very likely to be catastrophic- one that is capable to bring serious environmental, health and economic loss along with enormous psychological distress to many lives. Thus until the day which the nuclear industries and the governments' nuclear regulators worldwide can assure the people maximum safety environment for nuclear energy, we may be constantly living under the fear and threats of hundreds of powerful time bombs that one day may be trigged to become the next Chernobyl!

Reference

Meshkati, Najmedin. March 28, 1989. Are we safer after Three Mile Island?

Los Angeles Herald Examiner. A17

Specter, Michael. March 16, 1996. 10 years later, through fear,

Chernobyl still kills in Belarus. The New York Times. 1, 4-5

Shcherbak, Yuri M. 1996. Ten years of the Chernobyl era. Scientific

American. 44-49

Kerber, Ross, NRC May Close Two Plants Owned by Northeast Utilities,

Citing Safety. The Wall Street Journal,4-11-1

Wald, M. March 9, 1996. Safety Deadline Set By Nuclear Agency For 2 Power

Plants. New York Times, A7996, A-16.

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What Have We Learned From TMI 17 Years Later? Implications For Future Chernobyls

Name : Mel A. Wong

E-Mail: mela@ucs.usc.edu

ISE 370L

April 1996

UCS Systems and Networks Support Phone:(213)740-5308

WWW: http://www-scf.usc.edu/~melan Pager:(213)990-7632

E-mail: mela@skat.usc.edu

[Introduction]

The accident at Three Mile Island (TMI) and Chernobyl had startling resemblance but a decade apart. Both accidents were contributed to chains of events linking plant designs, machine designs, control designs and the human factors together to one disastrous failure. Though rare, these accidents are inevitable with a fair probability of occurrence and a huge chance of mass distractions globally. With this in mind, we need to stop denying ourselves that another accident like this will not occur again and begin to reconsider what we have learned.

[Main]

Operating any reactor is a delicate balancing act. Unfortunately, this was not realized when most, if not all, of the nuclear reactors were designed. First, due to the nature that a nuclear reactor site is huge, the importance of a real-time system were not utilized. The displays that is supposed to show reactor event is not dependent on the event itself. However, the control towers are usually placed at a remote location leaving reactor technician only to rely on their displays. Second, the critical machines that is controlled by the technicians, are not built with enough quality. Though still a controversial issue, these machine due fail unpredictably. Third, is the design of the control panels. This is probably one of the biggest problem that plague all nuclear reactors around the world. There are absolutely no Human Factors taken into consideration. It is like have a time bomb control at hand. The following example illustrate such deficiencies in designs that can lead to a nuclear disaster like Chernobyl.

During the Chernobyl incident, the availability of the neutrons from the fissioning of the uranium and plutonium is required in the fuel to keep the chain reaction within the reactor at a desired level. Should the population of neutrons begin to fall, the power goes down, as do the chances of the reactor shutting down. If there is a sudden rise in the population of neutrons, there is a very likely chance that the operator will have a runaway nuclear reactor on there hands. During operation the reactor is basically controlled by inserting and withdrawing control rods made up of substances that absorbs neutrons. Reactors are designed so that if there is a full insertion of the controlled rods between the fuel packages will stop the chain reactions in its tracks.

Standard operating procedures demand that the power should not fall below 20 percent of full power. Unfortunately, in Chernobyls case, the technician in charge of controlling the reactors power level let it fall too far. The display gauges showed seven percent of full power, at which point he had to juggle with the reactor controls to prevent the reactor from shutting down all together. In the meantime he had disconnected various automatic safety devices, including the emergency shutdown mechanism. To raise the power from its low level the technician operated the control that lifted the control rods out of the core which reduced the flow of water through the pressure tubes. The reactor can become extremely sluggish in terms of response at this point. Now, as the technician continued to operate the controls, the chain of events begins to build up, so raising the power and generating more heat. The water begins to become steam, a process in itself that tends to generate more and more neutrons to contribute to the chain of events. Seconds after, the technician will have a runaway situation, as did Chernobyl, on his hands with the reactors power building up to more than a thousand times than what it had been moments before. At this point, the only choice is to shut-down the reactor completely by dropping in the control rods, but by then they had been raised out of the core and needed a few seconds to become fully inserted - far too slow for the chain of events that had been unleashed. Chernobyl came to a violent end as the chain of events lead to an explosion that blew the fuels apart.

[Preventative Measures]

Since no human activities can be shown to be absolutely safe or predictable, it is unlikely that any procedures and measures can reduce the risks to zero. We should aim for rules and safety systems to minimize he risk to the point where a reasonable individual would conclude that they are trivial. These preventative measures would have to include a total re-design of the controls and displays of the reactor systems. Massive training of employees must also be considered. At whatever stages, one must take into account the Human Factor aspect.

[Conclusion]

The anniversaries for Three Mile Island and Chernobyl has come and gone and remembered every year, but without celebrations. Though the two accidents were unfortunate, we should all, instead of dreading it every year, dedicate ourselves to find newer and safer solutions to reduce, if not, predict the probability of the inevitable catastrophic nuclear accidents in the future. What happened seventeen years ago at Three Mile Island, though minuscule in its health consequences, had widespread and profound effects on the American and international nuclear power industries.

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WHAT HAVE WE LEARNED AFTER TMI SEVENTEEN YEARS LATER

IMPLICATIONS FOR FUTURE CHERNOBYL

JIE GU

jgu@scf.usc.edu

ISE370L spring 1996

Because nuclear power plants do not burn anything, they are non-polluting and kind to environment. Unlike coal-, gas-, and oil-fired power plants, nuclear power plants do not emit carbon dioxide and other harmful greenhouse gases into the atmosphere. Worldwide, there are 432 nuclear power plants at work, contributing about 17 percent of the world's electricity supply. Some countries, like France and Belgium, rely on nuclear power plants to generate more than 50 percent of their electricity supply. Furthermore there are more than 40 nuclear power plants currently under construction, which will add an estimated 95 million kilowatts of new nuclear capacity to the world's electricity supply by the year 2010 to accommodate the expanding populations and economics of many Third World countries. (NEI, world wide webb page) In the United States, there are 109 operating nuclear power plants generating about 20 percent of our total electricity supply.

With such heavy reliance, it is not hard for anyone to realize the extreme importance of safety issues in these power plants as we all learned from the Chernobyl incident that a nuclear accident anywhere is a nuclear accident everywhere. In addition to the serious health hazards, economic losses, the long term environmental damage is also unthinkable. According to experts, it will approximately take several generations before Chernobyl zone, the area within 30 kilometers of the Chernobyl plant, become reinhabitable.

Based on the Chernobyl experience, plenty has been done or attempted to improve some of the safety issues. Many human factor engineers have devoted themselves to a better design of control rooms in nuclear power plants which will facilitate operation performance and reduce operator errors. Nuclear engineers and experts in other related fields had come together and designed better training programs and standards. In United States, NRC, the Nuclear Regulatory Commission, issued a series of regulatory measures aimed at improved safety after the TMI accident. In 1995, the government of Ukraine and the Group of Seven industrial nations signed a formal agreement on a cooperative plan to shut down the whole Chernobyl plant by the year 2000 because the Chernobyl zone is one the most dangerously radioactive places in the world.

All of these good news may lead the public to think that we are safer now. Unfortunately, many evidence suggest that we still have long way to go as far as running a safe nuclear energy program. As with such a large-scale technological system lies within three components(see chart below): manufacturer of reactors such as GE, operating companies such as Northeast Utility and TVA, the Nuclear Regulatory Commission, which regulates all commercial nuclear power plants in the United States. Only through proper interaction within these technological and human components, in addition to giving emphasis on each component individually, then we will have a safe system. As manufacturers of reactors, it has to not only design a better reactor system but also communicate with other components, inform them if there are any problems. As operating companies, it has to develop detailed training standards and qualification guidelines, also give feedback to the manufactures. At last, the regulating component, the NRC, has to oversee both the construction and operation of nuclear reactors and nuclear facilities. If any of these three components is not doing its job, the structure is not balanced, we will not achieve our goal of having a safe nuclear energy program.

Regulators

Operating companies Manufacturers

After reading the reports on two engineers at Northeast Utility blew whistle on nuclear safety of company’s plants but was discouraged even harassed by some officials in the company, I was shocked to learn the sloppiness of these operating companies and the NRC in dealing with safety issues in nuclear power plants in the United States. Obviously, both the operating company and the regulator components are not doing their job properly. Northeast Utility, in this case representing attitude of number of companies in this industry towards implementing safety procedures, is trying to corner-cutting on safety in order to be more competitive. According to Thomas T. Martin, the NRC's top administrator for the regions, Northeast Utility has appeared to emphasize profits at the expense of safety since the later 1980's (The Wall Street Journal, March 11, 1996) On the other hand, the NRC with its mission being: to ensure adequate protection of the public health and safety, the common defense and security, and the environment in the use of nuclear materials in the United States, failed to enforce its own rules.

Although it has been seventeen years from the TMI accident and ten years from the Chernobyl accident, we may have better solutions to safety issues existing in nuclear power plants, better design of the system, better training programs, even better regulatory policies, without proper interaction between these technological and human components, future Chernobyl's are inevitable! I urge leaders of this industry to take this safety issue more seriously, please do not only look at the short term profit by ignoring safety problems, for humankind can not afford another Chernobyl!

Reference

Meshkati, Najmedin. March 28, 1989. Are we safer after Three Mile Island? Los Angeles Herald Examiner. A17

Specter, Michael. March 16, 1996. 10 years later, through fear, Chernobyl still kills in Belarus. The New York Times. 1, 4-5

Shcherbak, Yuri M. 1996. Ten years of the Chernobyl era. Scientific American. 44-49

Kerber, Ross, NRC May Close Two Plants Owned by Northeast Utilities,Citing Safety. The Wall Street Journal,4-11-1

Wald, M. March 9, 1996. Safety Deadline Set By Nuclear Agency For 2 Power Plants. New York Times, A7996, A-16.

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What have we learned from Three Mile Island 17 years later ? Implications for future Chernobyl(s)

Herman Tjahjadi

Email: htjahjad@aludra.usc.edu

ISE - 370L

SPRING - 1996

A. The Way The TMI Incident Happened The incident initiated with a blockage in the plants giant water filter. The blockage resulted in the leak of moisture into the air system, inadvertently tripping two valves and shutting down the flow of cold water into the plants steam generator. The backup cooling system designed with purpose to handle this kind of emergency did not function. The backup system valves were closed. No one knew that since the indicator in the control room telling the status of the valves was blocked by a repair tag hanging from a switch above it.

Actually, the system had another backup system, a relief valve, but it was also not working either. And to make the emergency even worse, a gauge in the control room which should have told the operators that the valve was not working was itself not working !! By the time TMIs engineers realized what happened, it was already dangerously close for the reactor to a MELTDOWN.

B. Nuclear Power Plant Accident and Its Danger

-----------------------------------------------

TMI incident is an example of the so-called Normal Accident. Normal Accident states that given a highly sophisticate and complex system, it is likely that some combinations of minor errors will eventually amount to something catastrophic. To make a much clearer how TRAGIC a nuclear plant meltdown could be and to describe TMI incident as a normal accident, let us relate the topic with that of the Chernobyl incident.

B.1. A Nuclear Accident Anywhere Is A Nuclear Accident Anywhere

----------------------------------------------------------------

Chernobyl is considered as the worst technogenic environmental disaster in history.The radiation released after the Chernobyl explosion was approximated to be 200 times that of the combined releases from the bombs at Hiroshima and Nagasaki in World War II.Regions affected included not only Ukraine, but also included are Belarus, Russia, Georgia, Poland, Sweden, Germany, Turkey, Japan and others.

B.2. Totally Damaged Environment

---------------------------------

Gomel, which once was the most productive region in Belarus, is dramatically changed.Today, of the 21 agricultural districts it consists, only one produces crops. In Poland, Germany, Austria and Hungary, crops and milk were so contaminated that they had to be destroyed.

B.3. Effects on Human

----------------------

Approximately 20 million former Soviets were exposed to radioactivity released at Chernobyl. In 1981-1985, the number of thyroid cancer cases in Ukraine was about 5 per year. In 1986-1991, the number increased to 22 cases per year. However, during these last five years, the number has even increased to about 43 cases per year. The number of pregnancies with complications has been growing among women living in the affected area. People in those areas have become paralyzed with fear. They are afraid to marry and afraid to have families. It seems that as if the Chernobyl incident is still occurring through the a new way of attack, the psychological one, the deadly FEAR.

B.4. Costs

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It is estimated that $400 billion and 200 hundred years will be consumed to totally wipe out the effects of the accident in the affected areas and $26 billion was allotted for the resettlement of the 200,000 people still living in those areas. Recently, G7 Countries and the Government of Ukraine have developed a cooperative approach on the elaboration and implementation of a comprehensive Program to support the decision of Ukraine to close the Chernobyl nuclear power plant by year 2000.

C. Recommendation

------------------

Being aware of the tragic incident described above, here are some recommendation that deserve careful and critical thoughts:

1. Create a work condition in nuclear power plant which MOTIVATES and APPRECIATES any safety concerns from the workers. Recently, there have been an increasing trend for nuclear plant engineers that raised some safety concerns but were forced to undergo psychological treatment in a way intended to keep them away of the problems. The management does not like their concerns because it will cost a huge amount of money to adapt the correction steps of the problems. The management response should always make public safety the first priority and the response should be quick to any reported safety concerns.

2. Nuclear Regulatory Commission should ALWAYS takes an active role in enforcing the law requiring any nuclear plant power strictly adhere to the existing law and specification Without any strong action from NRC, there will be more and more plants will operate under danger condition due to the lack of adherence to the safety specification. They are like ticking time bombs that can explode in any time. If NRC is asleep, another TMI or Chernobyl incident is not just likely, but will be INEVITABLE.

3. Training should include more real simulated emergency situation In order for the operators to response accurately and fast, the training program should be designed that the they will be ready for any emergency. From TMI incident, the operators confessed that actually they did not know the cause of some initial peculiarities happened with the reactor.

4. Human factors design is a vital aspect of safety operation of a Nuclear Power Plant Ideally, the human factors specialist should be involved at the stage of the concept development or the preliminary design stage. Since the TMI incident, the NRC, the power industry and the human factors community have been struggling with the basic issue of how best to enhance existing operational and near-operational power plant control rooms from the human factors standpoint.

5. There should be a good mutual understanding and cooperation among Nuclear Regulator, Nuclear Power Plant Management and Nuclear Power Plant Manufacturer. Only if they work together and have the understanding and cooperation will the safety and reliability of a nuclear power plant can be assured so that the probability of any incident will be minimized in the short run and eliminated in the long run.

D. References

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1. A Few Observations, Questions, and Comments on MOU By : Dr. Najmedin N. Meshkati

2. The Critical Role of the United Nations in Ensuring the Safety of Nuclear Power Plants Around The World By : Dr. Najmedin N. Meshkati

3. Article 10 Years Later, Through Fear, Chernobyl Still Kills in Belarus from The New York Times, Sunday, March 31, 1996

4. Article Blowing The Whistle On Nuclear Safety from Time Magazine, March 4, 1996

5. Article Was Therapy Used to Punish Nuclear Workers ? from The Wall Street Journal, Wednesday, March 20, 1996

6. Remedial Human Factors Engineering from : Applied Ergonomics, 1983, 14.4, 253-264

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What have we learned from TMI 17 year later? (Implication for future Chernobyl)

Gee Ansavananda

Email: ansavana@scf.usc.edu

Nuclear power plant is the answer for many countries around the world as a mean in gaining their independent from other countries for import energy. There are currently 436 nuclear power plants in operation around the world, and 96 more are under construction (IAEA Bulletin, 1/1990). On March 28, 1979 a partial meltdown occurred at the Three Mile Island (TMI), and only seven years later a totaled meltdown occurred at the Chernobyl nuclear power plant in northern Ukraine. The meltdown at the Chernobyl caused at least 300,000 deaths. Twenty percent of the country farm land are no longer exploited due to high radioactive contamination (Foreign Policy, U.N. 50th Anniversary). The effect of the explosion was felted all over the world, "Russia, Georgia, Poland, Sweden, Germany, Turkey .... Even such distant land as the U.S. and Japan received measured amounts of radiation." (Scientific American, April 1996) The fear does not end with the fire and the explosion at Chernobyl, it continues to haunt us up to this day. Now there is a fear of the 2,000 metric-ton metal sealed that was blown off from the explosion and now rest dangling between two points inside a crumbling structure, if this metal plate was to fell through the building, it will propel massive highly radioactive dust cloud into the atmosphere where mother nature will reminded us of the disaster all over again. Chernobyl will continue to haunt us for at least another 190 years to come because "it will take up to 200 year to "totally wipe out" the effect of the accident". (Industrial Crisis, Vol. 5, 131 - 154) The cause of both the TMI and Chernobyl accidents could be link to three main reason Human Error, oversight of regulatory body, and management short cutting necessary expenses. Significant information have been collected as to the cause and effect of these accidents but little of these information have been implemented to improve the safety of the current and future nuclear power plants.

Human error was sighted as a core cause of the TMI and the Chernobyl accident. The word human error maybe misleading in the way it highlights the word human, as to imply that the reason the accident occurred was the cause of the human operators incompetence. On the contrary, the two words implied that the reason an accident occurred was because of the lack of Micro and Macro-ergonomic consideration at the early design stage of the nuclear power plant. The human mental work load limitation, compatibility of the control at the work station, and the overall organization of the plant are some of the issues that are attracted by the Micro and Macroergonomic level. Without the human factor consideration in the design stage of the plant the finish product is call human machine mismatch. An example of "human-machine mismatch" was at the TMI accident where the operator was not able to tell if the Pilot-Operated -Relief-Valve (PORV) was open or close because there was no indication of the position of the PORV any where in the control room--this was the main reason why the accident progressed as far as it did. Extensive research have been done to improve the human machine interface but most of the commercial nuclear power plant today still have "NOT" implemented any of the finding into the current or the future design nuclear power plants. (Dr. Najmedin Meshkati)

The Nuclear Regulatory Commission (NRC) is like the police officer to all 110 of the commercial nuclear power plants in the United States but is currently under close watch for ignoring to catch the murderer. Every time a commercial nuclear power plant violate their license to operate, they are putting million of people lives in danger of dying, risk of thyroid cancer, heart attack, and psychological illness -- a known result of a nuclear holocaust (Chernobyl). In a recent shut down of two Northeast Utilities nuclear power plant, the NRC have failed to see that the plant have been operating delinquently for "20 years." (Time, March 4, 1996) The NRC also have the power called "enforcement discretion" which allows then to waiver any safety issue they see fit. Instead of closing the plant down for violating the safety standard "the federal watchdog turns a blind eyes" and "issuing 15 waiver" to the power plant (Time, March 4, 1996).. The NRC has failed to realize that there are much greater cost at stake -- lives of innocent people. We relied on NRC to oversee and ensure safe operation by the 110 nuclear power plant in the United States but they failed to understand the crucial part of their job -- to ensure safe operation on all 110 nuclear power plants.

Plant management is another governing body of the nuclear power plant that has the power to set the safety standard. Instead of setting the standard for being the safest nuclear power plant in the world they have chosen to race in the opposite direction. They are competing to see how much safety violation they can get a way with before they are caught. Northeast Utility even went as far as rewarding those employee who does not raise safety issue and firing those who does. Those who raise the safety issue will first be psychological test. The test result will then be use to discredit the employee, and a reason to terminate their job.(The Wall Street Journal, March 20, 1996) We need to enforce the safety issue to a more personal level to these management. Instead of just shutting down the nuclear power plant for violating the safety issue, the management should have a personal at stake to loose. So personal that they will feel the pain of every child out there dying from nuclear holocaust.

TMI and Chernobyl have shown the world what an impact a nuclear power plant holocaust is capable of destroying when safety issue is not taken into consideration. A disaster that will continue to claim many innocent children lives with such illnesses as leukemia, cancer, and what is known as Chernobyl AIDS(Scientific American, April 1996) for century to come. Knowing that the key factor in both the, TMI and Chernobyl, incidents was the lack of Micro and Macro-ergonomic consideration--to improve the human-machine interface--in the early design stage of the nuclear power plant; and up to this day 110 commercials nuclear power plant still operating under the same original design of TMI, and Chernobyl. It only took one missing indicator (PORV position indicator) to create a partial meltdown at the TMI, but the Northeast Utilities violated 15 safety standard with the help of the NRC enforcement discretion waivers. Combining these known facts, it is certain that we will face another nuclear holocaust. "THOSE WHO IGNORE HISTORY ARE FORCED TO RELIVE IT." (George Santayanas)

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What Have we Learned from Three Mile Island?

Seventeen Years Latter, Implications for Future Chernobyls

Name: Alsafi Turki

Class:ISE 370

E-mail:Alsafi@girtab.usc.edu

The basic reason for attempting to harness atomic energy remains. Once the initial expenditure is made, secured by public bonds or the investment of some utility company, cheap electricity for an energy hungry world drives the market (Meshkati, 1989). The use of a natural resource to provide heat and light for paying customers is not necessarily a bad thing. Yet somewhere along the line the mix of complex technologies, unforeseen situations, and human beings, will create problems. Richard Feynman, the late Nobel physicist commented that, "for a successful technology, reality must take precedence over public relations, for nature cannot be fooled" (Meshkati, 1989). This refers to the tendency for human beings to concentrate their endeavors too heavily in one area and not take into account a more holistic approach to problem solving. Technologies always present problems because they are controlled subversions of natural processes. The controlling elements eventually break

down.

What has not been learned from Three Mile Island is that public safety should be the overriding concern of any energy- producing utility. After Three Mile Island solutions to ensuring the safety of large scale technological systems have fallen into the categories of management and cost control. In these areas, safety may sometimes be jeopardized in order to save time and money. Glenda Kay Miller, a security engineer at the Browns Ferry nuclear plant near Decatur, Alabama, questioned the reliability of a proposed employee-identification system. The Tennessee Valley Authority saw fit to refer Mrs. Miller to a company psychologist, rather than investigate her observation. The U.S. Nuclear Regulatory Commission is currently investigating claims that Northeast Utilities, majority owner of the Millstone nuclear-plant complex in Waterford, CN has routinely harassed workers criticizing safety procedures (Kerber, 1996).

The failure of workers to recognize the connections between systems engineered to effect safety, shows a lack of holistic vision in regard to nuclear power. On the night of the Chernobyl accident, operators were conducting a test to see how long the generators would run without power. Unfortunately, the Chernobyl reactor RBMK-1000 has a design flaw that makes its operation at low power unstable (Shcherbak, 1996).

Very often, an error is the effect of complicated operational processes, ineffective training, non-responsible managerial systems, non-adaptive organizational designs, and haphazard response systems. At Three Mile Island, operators trained for a series of accidental events, not an isolated incident (Meshkati, 1989). It is widely accepted today that complicated systems failures can be traced to the way engineered and human factors fit together and how they interact. The lessons of Chernobyl, the generation of electric power without the proper consideration for public safety or the necessary dissemination of information were not completely lost on Three Mile Island. A disaster was averted. But not all solutions are found in better engineering.

References

Meshkati, Najmedin. Are we safer after Three Mile Island? 3-28-1989, Los Angeles Herald Examiner, A 17.

Kerber, Ross. Was Therapy Used to Punish Nuclear Workers? 3-20-1996. The Wall Street Journal, B 1.

Shcherbak, Y. M. Ten Years of the Chernobyl Era. 4-1996. Scientific American, pp 44

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What have we learned from TMI 17 years later:

Implications for the future Chernobyls

Andry Kusnowo

akusnowo@aludra.usc.edu

ISE 370 L

1996

In this ever changing world, man kind always try to invent something in order to improve their lives. One major improvement that I want to discuss is the improvement in Nuclear Power Plant. In a nuclear power plant the main objective is to produce electricity by harnessing the heat released during the fission process. As a result of this fission process certain radioactive materials or elements are produced. In the nuclear power industry, I have learned that the improvements of remedial human factors techniques are really required. It is an historical fact that, first, fossil plants and subsequently nuclear power plants were designed with little or no formal attention to human factors engineering. (Seminara et al, 1976). This was not a cause of great concern until March 1979 Three Mile Island accident which focused public, power industry and regulatory attention on human factors engineering deficiencies associated with power plant control. So, in this paper, firstly, I am going to discuss about the TMI accident, and observed the causes, the effects, and the future implications especially in the Chernobyl Nuclear Power Plant.

In the Three Mile Island nuclear power plant, the biggest error that cause the incident is the human factor errors. First, the major error located in the design of the control room of the nuclear power plant. When the engineers design the control boards, there are a lack of clearly defined relationships between control-display elements (Seminara et al, 1976). The problems was compounded when the panels are identical in appearance-size,shape, color and texture, distributed in sterile, symmetrical patterns that offer no orientation or location cues regarding the identity of a specific panel elements Vs on of its many identical twins. Also there are no obvious sub-grouping of the components. The problems inherent in such panel designs become manifest when one walks through an emergency procedure with a relatively inexperienced operator and observes the halting search attempts to locate a specific control or display. Furthermore, in the Three Mile Island nuclear power plant accident, there are some lack of attention from the manufacturer, the Nuclear Regulatory Commission, and the operators. Because of these lack of attention, or maybe due the expensive costs of the attention, the TIM accident was unavoided.

Prior to the TMI accident, it was evident that much could be done and should be done to ameliorate existing power plant control boards. The operators, who are dealing with those control everyday, had tried to solve those problems, either by reported it to the design engineers, or even the head of the company. Since the cost to enhance, fix, or to re-design the control board was so expensive, there were nothing had been done, except those from the operators themselves. For example, they had drawn something on the control panel, or sub-grouping the control panel by themselves. Meanwhile, the NRC, who should check and regulate every single thing about the safety of a nuclear power plant, they (NRC) was not doing their job properly in the TMI accident, especially about the opening valve of the coolant. Even though it seemed as a small thing, the opening valve was the major cause of the TMI accident.

After several investigations that cause thousands or even millions of dollars, the government finally found pout the causes of the accident, and they made the TMI accident as a lesson for a nuclear power plant industry. From that time, there are several improvements that people make in building the next nuclear power plant, but there are a little improvements that had been done in many of the existing nuclear power plant such as Chernobyl, since again it coincide with how much money should be invested or spent to improve it.

Seventeen years after the TMI accident, on April 26, 1986, one city became the focus of the nations. It was in Ukraine, at the Chernobyl nuclear power plant. The explosion turned Chernobyl became the worlds foremost symbol of the technological disaster. The cause of the explosion was actually similar to the TMI accident 17 years before. The events that led up to the explosions are well known. Reactor number four, which produced steam that drove generators to make electricity was involved in the test, where operators want to see how long the generators would run without power. For this purpose, they greatly reduced the power being produced in the reactor and blocked the steam to the generators. Unfortunately, it has a design flaw that makes ots operation at low power unstable. In this moide of operation, any spurious increase in the production of the steam can boost the rate of energy production in the reactor. In addition, the operators had disabled safety systems that could have averted the reactors destruction.

Realizing belatedly that the situation had become hazardous, an operator pressed a button to activate the automatic protection system. The action was intended to shut the reactor down, but by this time it was too late. Just in three second, there reactors core surged to 100 times the normal maximum level, and there was a drastic increase in temperature , the result was a big explosion that release the dangerous fission product, such as uranium, plutonium, iodine 131, strontium 90, and cesium 137. Because of the unclear relationship between the operators and the control board, the destroyed reactor liberated more radiation than was produce by the atomic bombing of Hiroshima and Nagasaki. The area included agricultural land within 18 mile radius from Chernobyl tainted by the ultimate modern poison, considered too polluted for human habitation, and also radiation was deposited unevenly across the region, with some villages heavily contaminated and other neighboring villages almost untouched.

This Chernobyl accident became the nightmare not only for the people on that area, but also the world. People that lived in that area have been paralyzed with fear, they are afraid to move, afraid to stay, afraid to marry, and afraid to have families. Every thing becomes nightmare, all living creature in the surrounding area were dying and contaminated with the ultimate poison like cesium 137. All normal life stopped here simply because the explosion on April 26, 1986. Why ? What is the major factor that reasoning behind it ? The major reason behind these accidents, which I believed after I study many articles about Chernobyl, was simply because the money that have to be spend in order to design a good nuclear power plant, especially in the control board area. The nuclear power plant industry should realize that the cost to make some improvements in re-design the control board to become more ergonomics to the user was nothing, compare to the problem that cause by the nuclear power plant such as Chernobyl. We have to realized that the price of human being cant be measure compare to the price or cost to improving the nuclear power plant workstation. Also the cost to clean up the mess that caused by the nuclear power plants are much more expensive. Like in the Chernobyl accident, the government already devotes more than 15 % of their GNP - a total of more than $235 billion over the last decade- to paying the cost resettling tens of thousands of people, as well as the medical and social bills growing from Chernobyl, and it is still not enough. (New York Times International, Sunday, March 31, 1996)

By looking at the Chernobyl accidents, the world attention has been focus on the nuclear power plants. Many improvements have been done to maintain the safety of the nuclear power plants. The reality is that there are no simple answer to the range of the health, environmental, and money problem created by nuclear power plant, especially Chernobyl. Eight times in the last decade the leaders of Ukraine have decided to close the giant facilitys remaining three reactors. And eight times they changed their minds because shutting the plant would strip 5,000 jobs from a region that already devastated economically (NYT, Sunday, March 31,1996). However, there are still many occasion where people in the nuclear power plant businesses, forget about the importance of the safety in this power plant.

Ten years after the disastrous uncontained meltdown at Chernobyl, 17 years after the partial meltdown at Three Mile Island, most Americans probably give only passing throughout to the issue of nuclear safety, especially for the Nuclear Regulatory Commission. Recently, two gutsy engineers in Connecticut have caught the NRC at a dangerous game that has been proved exist for years where they (NRC) routinely waiving safety rules to let plants keep costs down and stay on-line, just like in TMI accident. The NRC relaxed standards and granted license amendments that allowed plants to re-rack their rods in ever more tightly packed pools (Time mag.,vol. 147 no.10, p.50). Furthermore, in 1990, Northeast Utilities engineer discovered that the instruments that measure the coolant level inside the reactor at Millstone 3 were falling, just like in TMI accident. But the engineer was forced out, and the problem went uncorrected due to the costs and the time that the plants need to shut down. Last December, again, a worker at the Maine Yankee plant in Bath charged that management had deliberately falsified computer calculations to avoid disclosing that the plants cooling system were inadequate.

From all of those words that I said, I learned a lot of things in the nuclear power plants. I am positive that the most important thing that the people in the nuclear power plants businesses have to look out is the design of the control room and also the regulation of the safety in the nuclear power plant. By looking at the last paragraph of my paper, I conclude that the NRC has not focus nor awake by the accidents from TMI and Chernobyl. They have to see and learn that costs to maintain the safety is nothing, compare to the cost that they have to pay if there are some accident that is happening, like Chernobyl or TMI. For NRC, eventhough they think that responsibility for safety rests with the industry, and eventhough they are essentially auditing agent, I think they are really the one that has to watch the nuclear power plants as the representative of the consent of the people of the United States of America. They must really be strict and straight about the regulation of the nuclear power plant, and they must stop the dangerous games that they have been played for years : routinely waiving safety rules to let plants keep costs down and stay on-line. From what I have learned about these nuclear power plant businesses, I really become more concern about how the industry make their improvements for their plants, especially the control board room, and how the NRC doing what they have to do. In my opinion, it is so much better to spend few more budgets on safety precautions rather than be sorry later on.

ANDRY KUSNOWO

10746 Francis Place # 261

Los Angeles, CA 90034

(310)838-1199

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Andy C.H. Lin

chinghen@scf.usc.edu

ISE 370L

1996

There are about 429 nuclear reactors on Earth. Every nuclear power reactor in the world has explosion power equivalent to one thousand Hiroshima bomb. The result of meltdown of reactor can affect large area of people and environment. According to Scientific American about Chernobyl which located in northern Ukraine, "the regions affected included not only Ukraine itself but also Belarus, Russia, Georgia, Poland, Sweden, Germany, Turkey and other." Some of the areas are heavily contaminated for people to live and agriculture, so people are forced to move out. One-fifth of the republic of Belarus' more than 10 million people have to be moved out due to the result of Chernobyl, and 10000 farms an d four million sheep are also affected. . Thousands death results with Chernobyl's accident, the estimation of Ukraine is 32000 deaths. The radiation also causes the thyroid cancer, pregnancies with complications, neuropsychiatric disorders, and so on. These can take many years before they become detectable. Therefore, the real number of death is probably higher than 32000 deaths. In fact, according to The Economist, the accident may yet cause up to 300,000 deaths. The cost is tremendous due to the resettlement of the people, and it is estimated to be about 600 billion dollars. All of these negative results are simply caused by meltdown of nuclear reactor.

Ten years after the meltdown at Chernobyl, seventeen years after the partial meltdown at Three Mile Island, the world are not much safer than what it was before. In American, Nuclear Regulatory Commission is in charge of inspection of the nuclear reactor which are mostly owned by private company. But NRC hasn't been doing their job, many nuclear reactor in United States is not operating with safe and standard procedure. Millstone Unit 1 nuclear plant in Waterford has trouble with their spent-fuel pool which is used to store the used fuel rods, because the Federal Government has never created a storage site for high-level radioactive waste. One of the nuclear engineer in the plant has indicated that if Millstone lost its primary cooling system of the fuel-spent pool, the pool can boil, and this is confirmed with the consultants. This results the radioactive steam which can cause variety of damages. NRC has known about the procedure for a decade without moving to stop it. Moreover, the plats in Delaware, Nebraska and New Jersey have similar fuel-pool troubles, and NRC is sitting on a nationwide problem. According Time, "It all comes back to money. When a safety issue is too expensive for the industry, the NRC pencils it away. " The whole issue here is that the NRC has "not" enforced the regulation which puts not only the United States, but the entire world in danger. Even the NRC chairwoman Jackson has said, "We haven't always been on top of things. The ball got dropped. Here's what I'm saying now ; The ball will not get dropped again." United States cannot afford to make mistake on nuclear issues, because it is going to cost us too much.

The employee with concern about the safely procedures are sent to the psychological therapy is another issue in the nuclear industry. The case, we have raised above the engineer who discovers the problem of fuel-spend pool is the victim of this issue. According to the Wall Street Journal, the management in some nuclear plant send their employee to the therapy as a punishment, when they criticize the problem in the plant. Although NRC has about psychological testing of nuclear-plant workers, the management is abusing it to harass whistle-blowers. The motive of this action can be the cost to the company over the safety issue which is raised by the employee. Those issue can cost millions of dollars to correct. As a result, this action have made the nuclear plant becoming a huge nuclear bomb, because the safety issues are constantly being erased by the management.

In Russia, there are 58 Soviet-designed nuclear reactors, and 16 of them are Chernobyl-type reactors. All of them are still operating. This also raises human's concern about the safety of these reactor, since the Chernobyl have bring one of the biggest technological disaster. Western engineer believe that at least 26 of these reactor should be closed as soon as possible. According to Los Angeles Times, the author has described those reactor as "bombs temporarily generating electricity".

In conclusion, we as human cannot afford to have anyone of these nuclear reactor to explode, because the consequence of it is too large. And many innocent life is going to sacrifice. The human cannot wait till some reactor blow up, then they start to investigate the cause of it. That is going to be too late. Hopefully, people can start to be aware of this issue and provide any tragedy from happening.