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PART 3 Continued
RADIATION AND THE PRODUCTION OF ENERGY
3-4 The possibility of nuclear disaster. Consciously or unconsciously, people who are generally unfamiliar with nuclear science often are concerned about the possibility of a devastating bomb-like nuclear explosion caused by some failure in the control of a nuclear power reactor. This is not an unreasonable or unexpected source of fear, since most people's consciousness of nuclear energy came from the nuclear bomb explosions in Japan that ended World War II. These were indeed devastating - probably exceeded only by the all-out conventional bomb attacks on England, on Dresden, on Hamburg, and on Tokyo during that war..
Since the discovery of nuclear fission (atom splitting), the public has been saturated with alarming stories and exaggerations about nuclear energy, probably because alarming news sells newspapers. The idea is sometimes put forward that any one of our nuclear reactors could, at any time, explode like a bomb. The accident at Chernobyl is frequently described as being a nuclear explosion. It was not. Terms, such as "melt down", "China Syndrome" or "bomb" are commonly employed to oppose the development of nuclear power or nuclear anything. The statements appear so frequently that the public believes them to be reasonably immediate possibilities But the truth is, the dire situations that are described simply cannot occur in this country, if anywhere.
First of all, no nuclear power reactor can explode like a nuclear bomb; it is physically impossible. Accidents are physically possible in which reactors overheat, and their components, depending on their materials, melt or catch fire, and steam produced from heated cooling water can be explosively released. However, plants are designed to minimize the chance of such accidents and mitigate their severity.
Secondly, all nuclear power plants in the US are in extremely secure sealed containers. These are designed to prevent any radioactive debris, resulting from some kind of operating accident, escaping into the environment. The accident at Three Mile Island afforded an outstanding demonstration of the security of the containment systems in use in the United States. The escape of radioactive gases during that accident was unimportantly small. The level of exposures to a few of the people in the area were comparable with the exposures from a year or less of natural background radiation. Actually, the Three Mile Island accident could hardly have been improved upon, had it been a definitely planned test of the security of the containment system.
The Chernobyl accident was unquestionably a real mess. But it must be made clear that such an accident cannot happen in this country, for the simple reason that we do not use the type of reactors employed in the Soviet Union, nor do we permit nuclear-power reactors without safe containment structures. It took their particular kind of reactor and their particular kind of uncontained reactor building to have their particular kind of releases. This also produced a useful lesson. The accident, and subsequent fire, was a clear demonstration of the absence of the occurrence of a so-called "China Syndrome" situation. Conditions of uncontrolled burning of the nuclear material, described as being capable of boring a hole deep into the earth (all the way to China) did not happen. Lives were lost during the first two or three months afterwards - largely among those who got high doses trying to contain the fire and subsequently cover the radioactive residue with shielding material, to prevent further escape of radioactive debris. The whole story is yet to be told. Prediction of the likelihood of accidental occurrences is very complicated in itself, but knowledgeable and sophisticated studies of the likelihood of accidents to power reactors have been made. These have often involved the most conservative assumptions (By conservative, is meant the use of assumptions in which any errors are more likely to result in more frequent or severe, rather than less frequent or severe accidents). It is a reasonable conjecture that if an accident or failure occurs, it will be because some element in the chain of possible causes has been ruptured, or even overlooked. If no elements are broken, there will, of course, be no accident. So it will not be pretended that accidents will not ever occur in nuclear plants, or anywhere else.
In this country, possibility of a major explosive accident is essentially zero. The likelihood of a Chernobyl type of accident here, is zero. The future occurrence of a Three Mile Island type of accident cannot be ruled out; it is only reasonable to expect that one of these might occur occasionally, because the human element is always present to some degree. One thing can be said for certain, the likelihood of such an accident happening tomorrow is much less now than it would have been in the week before the TMI accident. Science, industry, and the government learned a great deal from that accident, thereby improving plant design and operations, further lessening the likelihood of there being another one. As already noted above, no one in the public was exposed to an appreciable amount of radiation as a result of the TMI accident. No one was injured in any way that can be detected. If any radiological health effect did occur, its cause can never be distinguished from the hundreds or thousands of other cancer causes to which the same public in the TMI area has been exposed.
While not offered in any sense as an excuse, an apology, or an evasion, it might be pointed out that the population of the world has, over past millennia, been subjected to devastating accidents, diseases, and natural events of a nature far more serious than the worst that has been envisioned for a nuclear reactor accident.
An interesting comparison of this nature has been made in a pamphlet prepared by the International Atomic Energy Agency, which says:
Think about these things and seriously consider the alternatives to eliminating the continued development of nuclear-produced electrical power in this country.
Because almost nothing we have or do today is free from various risks, we must learn to recognize and cope with them. We must learn not to worry about the minor risks or those that we can lessen, or even eliminate, with reasonable effort and cost. Of those risks about which we can do little, we must try to learn more about them and try to balance them with all other risks. Radiation from natural environmental sources is just one of the risks we must live with and must recognize as one about which we can do relatively little. Teaching an inadequately informed public is difficult because radiation is so commonly described as something sinister and dangerous -- "it cannot be seen or touched or tasted or smelled". But radiation is not unique in these respects. There are many more agents in our daily lives that can be similarly described and that carry more serious risks than radiation. We must not deceive or mislead ourselves by concentrating our attention on any single risk (like radiation) to the exclusion of other risks. Everyone must make choices in life. We cannot avoid it. But we can make reasonable and rational choices rather than unreasonable and irrational ones. Various radiation-related actions are receiving increasing attention at all levels of government, and public opinion is being increasingly sought regarding them. Today, critically important decisions need to be made regarding the uses of radiation in the fields of medicine, industry, and the production of energy. If this book helps to enlighten that decision-making process it will have served its purpose.
Sooner or later, each person who reads this book will have to make at least three choices concerning radiation uses and the exposures they entail. At some time in life, a health professional will want to make x-ray images of some part of your body. Many people today are increasingly concerned about allowing such x rays. A better-informed response is to realize that the dose of radiation varies widely among medical procedures and is generally less than the lifetime dose of radiation a person receives from nature. Excess medical exposures to patients and to doctors have long ago been curtailed with appropriate national and international radiation safety standards. Medical and dental x-rays should not be feared any more than any prescription medicine, But, just as unnecessary prescription medicine should be avoided, so also should unnecessary x-rays. If, for lack of understanding of the problem, or for other reasons, you feel concerned over the necessity of any particular x-ray examination, it is best to discuss with your health-care professionals what information they hope to obtain from the examination. Seek a second professional opinion, if you are not satisfied with the answer. The information in this book may help you, personally, determine whether the potential benefit is worth the very minimal and hypothetical risk. If the health-care professionals cannot adequately explain a real benefit, you might want to forego the examination at your own risk.
Another choice that has to be made is how to respond to the concern over radon in the home or workplace where it may cause an increase in the possible risk of lung cancer to the occupants, depending upon the dose. As explained in the book, this natural source of radiation may be significant in one particular home and not in another. All homeowners should test their homes and follow the recommendations of the Environmental Protection Agency which are available with most radon testing kits or testing sources. If the radon levels are so elevated that EPA guidelines suggest efforts to reduce those levels, it would be wise to make an effort to avoid or reduce exposures. Such an effort would not be very costly under most circumstances. As indicated in the book, the homeowner can simply try cracking the window open to allow a little more air exchange, and then retesting to see if that simple action is sufficient. We should not forget that radon has been around since before man began living in caves and has not seemed to cause any obvious epidemic of lung cancer. (That appeared after large numbers of people started smoking). It is not something new to fear; it is only something you may wish to measure, to evaluate, and, if appropriate, to remediate.
The third choice which will almost certainly face each reader, is the question of nuclear power. On this issue the reader may opt to vote pro or con -- either directly or through his congressman. The author hopes that the information provided in this book will enable each person to make that choice more rationally and to realize that a vote against nuclear power necessarily means a vote for other sources of energy which certainly carry their own risks. Informed and rational persons will balance those risks and consider the benefits of a secure power supply, rather than jumping to the conclusion that one alternative -- such as nuclear power -- is alone in carrying risks. Remember: literally nothing of value is free of risks. It is a matter of considering and comparing all alternatives and choosing the combination that you believe is best for yourself, your family, your community and your country.