Science in Christian Perspective
Benefits of Nuclear Power Outweigh Its Risks
Everett H. Irish
From: JASA 32
In response to the companion article1, I asked myself questions about nuclear wastes such as: Why do some people fear them? Flow should they be viewed in perspective? Could we ever get along without them? Hopefully, in this response these questions are answered and nuclear waste management will he better understood instead of feared.
In order to he both informative and brief, several approaches to responding specifically to the subject article were considered. These ranged from (a) writing a parallel article with a balanced presentation of facts and interpretations, to (b) selecting a few portions of the article for critique in depth, to (e) selecting numerous items for comment. Writing a complete article is not feasible in the allotted space and is also unnecessary; there are numerous publications on the subject in varying degrees of technical detail for interested readers .2-10 The last approach was selected because of its feasibility, directness, and breadth of coverage. The comments cannot be comprehensive; however, they hopefully are adequate to apprise readers about nuclear waste management and some specific issues raised.
Comments on Winchester Article
The companion article is one of the better articles written in opposition to nuclear power. Many of the facts are summarized satisfactorily; in particular, file description of the types of radiation (i.e., alpha, beta and gamma) and the categorization of the types of wastes (i.e., mill tailings, lowlevel wastes, transuranie wastes, etc.) are cited. In addition, quite a few of the factual aspects of waste management practices are correct, but there also are numerous misstatements of facts. Incorrect impressions or interpretations all too frequently are given when the article alludes to situations or explains information. In addition, the beneficial uses of nuclear power and its waste products are completely omitted from the discussion. The following paragraphs expand on some of these aspects with reference to specific examples from the text of the article.
The companion article arouses fear and anxiety more than it provides understanding about nuclear wastes.
For example, the risk-however small-of radiation causing cancer is presented as the ultimate measure of safety without recognition of many risks of other types. Imagery and associations are also used for this purpose to allude to situations rather than deal with documented facts in perspective. Numerous examples (quotations in italics) can be given:
Radioactive wastes from commercial and military production are already more abundant than all the water in the world's oceans could dilute without risking dangerous re-concentrations of radioactivity in marine organisms and sediments. Possibly true but irrelevant. Even if so, the total toxicity (lethal doses) of nuclear wastes, aged 100 years, which would result from an assumed all-nuclear U.S. electric economy annually would be several orders of magnitude lower than the lethal doses of commonly used chemicals (e.g., arsenic, barium, hydrogen cyanide, et. al.) annually present in the U.S.A6 It has also been shown that the toxicity of the plutonium which would go to waste (projected for the year 2000) is comparable to the toxicity of lead sent to waste in 1973.11 However, such quantitative representations of potential hazards are virtually meaningless unless one also takes into account the barriers that prevent or retard movement in the environment and the possible pathways that hazardous materials could take to reach man; that is what nuclear waste isolation is all about, as discussed later.
The tragic limit over which human hubris may have tripped is that nuclear waste stays poisonous practically forever. "[he tragic limit" of what? The potential of nuclear power to provide a long-term supply of energy is a major step (not trip) toward ameliorating a growing world energy shortage. Furthermore, whereas arsenic, barium and lead are stable and will last forever, radionuclides decay; in fact, after about 500 years of decay, the radiotoxie hazard of high-level waste from the light water reactor industry will be lower than that of the ore that was required to make the fuel."12 This suggests that isolation time frames of 500 years are most important for isolation of high-level waste.
Alpha-emitters such as polonium and fissile plutonium 239 can be transported in any kind of a sealed container, even pockets' or briefcases, without harming anyone. True but irrelevant and misleading. (Polonium 210 is a radioactive isotope not normally considered a nuclear waste because of its presence in nature.)
...gammas penetrate through skin, sinew and bones well as through heavy lead, steel and concrete shielding Misleading statement because lead, steel and concrete are very effective shields.
It is worth asking whether the Nevada test-site disposal of liquid wastes could pass the skeptical scrutiny geologists, geochemists and hydrologists are currently giving to concepts for using geologic formations to isolate spent fuel and high-level wastes encased in steel and titanium. Yes, the practice would pass the scrutiny of knowledgeable persons. The wastes about which this allusion is made are estimated to contain less than 1 curie/year and are produced during metabolism and biological transfer rate research on both animal and plant life using radioactive and non-radioactive materials." Certainly the radiological safety of the practice is not in question.
Intermediate-level waste liquids produced at Oak Ridge National Laboratory are injected into a deep underground shale bed after first being mixed with grout. The grout solidifies and is intended to fix wastes into place. Whether it does or not, over the very long periods that some of the waste remains radioactive, will remain in question for many thousands of years. The safety of this practice is well documented" and accepted by knowledgeable persons as being entirely satisfactory. Earlier comments are also apropos.
The fact that radioactive particles can travel through the air has been widely known since Hiroshima. It became more immediately apparent at Three Mile Island. Linking Hiroshima and Three Mile Island is technically irrelevant but evidence of scare tactics. Movement of particles through air has been known since before the days of Tyndal's research.
The final IRG) report, produced by representatives of fourteen federal agencies, further advised the President, who is expected to make the key decision on geologic storage before this article is published... The intent of the statement can be implied, but no "key decision" was made by the President before the article was published, it is neither to be expected nor desirable that all decisions he acted on immediately, but rather that waste management policy evolve in an orderly manner, in consultation with the Congress.
The above examples show how imagery or allusions are used to create anxiety and fear about nuclear waste, in general. The companion article also contains numerous misstatements, misinterpretations or distortions of facts that lead to substantive misunderstanding of the subject. Some of these statements regarding radiation will he commented on as before with the hope of correcting misimpressions.
New information is released almost doily concerning heightened cancer incidence among workers exposed to low-level radiation. The reliability and validity of the information releases must he seriously questioned. Whereas radiation is easy to measure accurately with sensitive instruments, at low radiation levels valid data from which conclusions can he drawn are extremely difficult and time-consuming to achieve. The data on which some claims have been based, and the analyses involved, have been heavily criticized and discredited as is the case for the cited studies of Hanford workers;15 data from others such as the nuclear shipyard'' are highly qualified with regard to the interpretation of results.
Recently Ralph Nader's Health Research Group asked President Carter to act on a National Academy of Sciences recommendation that allowable occupational exposures to low-level radiation he reduced ten fold, from 5 rem to 0.5 rem per year. The National Academy of Sciences has not made such a recommendation. Continued study of the radiobiological basis for assessing the risk of radiation exposure per unit of dose equivalent indicates increasingly that the linear, no-threshold assumption represents an upper-limit and conservative estimate. In consideration of the risk now experienced in other "safe" industries, justification for a change is lacking unless a "double standard" were to he accepted by which occupational standards for radiation workers would be more restrictive than are safety standards for other industries."17
For 22 years the accepted wisdom has been that annual exposures of 170 mrem above background radiation levels was a permissible level for the general population. However, in 1977 the Environmental Protection Agency suggested 25 mrem as the annual limit. The Nuclear Regulatory Commission (NBC) has adopted that figure as the permissible dose to the public created by the nuclear fuel cycle. In taking over the role previously held by the Federal Radiation Council, EPA promulgated the lower limit, not on the basis of new knowledge about risk to the health and safety of the public but on what EPA believed the industry could live with.18 This is consistent with the philosophy of maintaining exposures as low as reasonably achievable and a credit to both government and industry.
Meanwhile cancer mortality is on the rise ... it seems evident that the release of carcinogens into air, water, or the food chain should be reduced rather than permitted to escalate over time. Nuclear power plants release much lower quantities of radioactivity than coal-fired power plants and also do not release the carcinogen benxo-(a)pyrene, the main cancer-causing agent in cigarettes, or large quantities of CU2, NO, and SO2, that have significant environmental health effects.6 Estimates show the lung cancer risk due to coal-fired power plants orders of magnitude higher than that due to nuclear power stations."19
The controversy about low-level radiation is both scientifically and politically complex. For the interested lay person complete understanding is unlikely, but a recent book20 has been written to provide information and helpful insights about bath aspects of the controversy.
Before the isolation of high-level wastes is discussed, some misstatements and distortions of facts related to New York State need to he commented upon:
Waste at West Valley neutralized with on alkaline solution has turned out to he very difficult if not impossible to remove from a carbon steel tank. There is no factual basis for this statement, A key report on the West Valley plant21 discusses removal of these neutralized wastes, potential difficulties, comparisons with tanks at the Hanford and Savannah River plants and removal methods, predicting more than 99% removal of the sludge. In March 1979, the technique and equipment were very successfully demonstrated at Savannah River.
The United States Deportment of Energy has proposed placing radioactive wastes 1000 feet below ground in a salt formation in the Finger Lakes region of New York State. This is a false statement. The subsequent statements are thus irrelevant and also gross distortions. However, in this connection mention should be made of the policy of "consultation and concurrence" that involves States at an early date in the repository site selection process.22 This process involves several years of geological/hydrological exploration combined with environmental impact assessments. The policy implies an ongoing dialogue and cooperative relationship under which the State effectively has a continuing ability to participate in activities throughout the process of evaluation of a potential repository site and, if it deems appropriate, to prevent the continuance of Federal activities.
Following the above allegation the companion article proceeds with a distorted and misleading discussion purportedly to show "why salt is the wrong media for a waste repository." In particular, the author presents an exaggerated conjecture of potential disaster based no an interesting phenomenon of brine migration under thermal gradients toward higher temperatures23 and potential movements of waste canisters in plastic salt.24 If brine inclusions were sufficient to reach canisters, the brine would corrode the canisters. However, this phenomenon apparently is a localized one involving relatively small amounts of fluid (e.g., a few liters per canister); therefore, the brine inclusions would be insufficient to corrode the canisters significantly and would also not provide a means of transporting radio-nuclotides away from a salt repository. With regard to potential movement of canisters, the article also conjectures an extremes scenario without factual basis. In reality, appropriately low thermal gradients and temperatures can be established during engineering of a repository system through use of variable parameters such as: (a) the predisposal cooling time for the waste; (h) the geometry of the waste canister; (c) the waste concentration in the canister; and (d) the spacing of the canisters in a repository.
Space does not permit commenting specifically on other numerous mistatements or misinterpretations included in this section; thus, reference is made to a relevant discussion of the subject for a perspective:"25
Expectations of extensive, undisturbed beds of dry salt may riot have been realized but niany researchers believe that the technical questions concerning salt will be resolved at least as promptly as those concerning other media, it not sooner. with its edge in engineering, salt may still be the first geologic environment selected for a repository. But other geologic environments have been under study all along, and their accelerated evaluation recently received a boost from the report 0f President Carter's Interagency Review Croup. Non-salt rocks under consideration include granites and basalts, which cooled in place from molten rock; shales, which are insets turned into rock by high temperature and pressure; and tuffs, which are volcanic ash solidified by its own heat.
A unique mined geologic repository concept that is not yet being investigated but has considerable merit is the controlled tunnel environment.26 An alternate to mined geologic repositories, seabed disposal (considered by the Interagency Review Croup on Nuclear Waste Management (IRC)), is also discussed in Reference 25. IRG found that disposal in mined geologic repositories is the nearest term option for implementation of the six candidate technologies studied .22
Engineering of a Waste Repository
The concept and safety of nuclear waste disposal in mined geologic repositories are discussed in numerous publications from general presentations for the laytnan6 to detailed environmental impact statements.9 The status of relevant technologies27 is dynamic because of the extensive research, development and demonstration work being performed in many countries of the world. Present scientific and technical knowledge is adequate to support siting and preliminary design activities.
The technical process of site selection can he considered as a set of information screens proceeding from general ideas to specific details, from large areas to small, well-defined ones, and from literature surveys to measurements in the field. The technology for exploration and characterization of repository sites is generally adequate to proceed, particularly because it has been well developed to fulfill other requirements for geologic exploration (e.g., for oil, gas and minerals). The information screening process involves a progressively more stringent investigation of site characteristics and evaluation with reference to specified criteria. Information obtained at each successive step permits reevaluation of uncertainties and the ability of the site and repository to meet regulatory standards. Such reevaluations lead either to a decision to proceed to the next step or to abandonment of the site.
Engineering of a waste repository requires consideration of numerous other factors in addition to those involving site selection. The construction of mined geologic repositories is based on available mining technology resulting from extensive, worldwide experience in mining for minerals and constructing caverns. however, engineering a repository also requires consideration of other aspects. The repository engineering is viewed and analyzed as a system. That is, the engineering will consider the cumulative effects of the hydro-geological, geo-chemical, and tectonic characteristics of the environment and potential future human activities, as well as the physical and chemical properties of the host rock chosen for waste emplacement, the waste form, and other engineered aspects of the repository. Thus, detailed, systematic, site-specific investigations and evaluations of these factors, including multiple barriers to radio-nucleotide migration, are used to engineer a repository.
Why hasn't a repository system yet been demonstrated? There are two major reasons. The first is that the present and projected volume of high-level wastes for tens of years is so small that it has not created an urgency. The second reason partly sterns from the first. From a technical standpoint, the time is being used to perform research and development work in order to determine the best designs of a system. As a consequence, a final system design has not been completed. However, the IRG has concluded that "successful isolation of radioactive wastes from the biosphere appears technically feasible for periods of thousands of years provided that the systems view is utilized rigorously."22
Space has not permitted discussion of the outstanding record and benefits of nuclear energy: (a) how it has provided reliable electrical energy for sections of the United States during extreme winter weather or coal strikes '21 (b) how it has benefited agriculture and reduced use of chemical insecticides;29 (c) how it can be used for sewage sludge disinfection for fertilizer use;3° (d) how it has been useful for space, terrestrial and marine power applications; etc. Even though its use has not been completely free of operating problems, I am convinced that the benefits of nuclear power outweigh its risks and that the potential impacts of significant energy shortages without it present greater hazards to humankind than the worst predictions of opponents to the continued and increased use of nuclear power.
Nuclear waste management can he and is being improved. I view waste management, like other aspects of the nuclear fuel cycle, as a set of engineering tasks and a set of political problems. Hopefully, the above will contribute to amelioration of the political problems so that the engineering tasks can he completed in time to provide needed energy for the future.
Chiseled into the monument to the Wright Brothers at Kitty Hawk, NC. is a challenge for the nuclear age:
In commemoration of the conquest of air . . conceived by genius, achieved by dauntless resolution and unconquerable faith.
1Winchester, Ellen, "Nuclear Wastes," Sierra, July-August 1979, pp. 46-51.
2Voss, J. W., 'Nuclear Wastes in Perspective," PNL-SA-7588, Battelle, Pacific Northwest Laboratories, Richland, WA, April 1979.
3Radioactive Wastes," NED of The American Institute of Chemical Engineers, 345 East 47th Street, New York, New York, 10017,1979,19 pp.
4Radioactive Wastes," IAEA Bulletin, Vienna, December 1978, 49 pp.
5Nuclear Waste Disposal," Atom, Volume 259, May 1978, pp. 122130.
6Cohen Bernard L., "The Disposal of Radioactive Wastes from Fission Reactors," Scientific American, 236, No. 6, June 1977, pp. 21-31.
7 "Report to The American Physical Society by The Study Group on Nuclear Fuel Cycles and Waste Management." Reviews of Modern Physics, 50, No. 1, Part II, January 1978.
8Alternatives for Managing Wastes from Reactors and Post-Fission Operatinsu in the LWR Fuel Cycle, ERDA 76-43, 5 Volumes, May 1976.
9Draft Environmental Impact Statement, Management of Commercially Generated Radioactive Waste, uoE/EIS-oO-ts D, 2 Volumes. Prepared for the U. S. Department of Energy, April 1979.
10Lapp, Ralph E., Radioactive Waste-Society's Problem Child, Rrddy Comunications, Greenwich, Connecticut, 1977.
11Cohen, Jerry J., "A Systems Analysis Approach to Nuclear Waste Management Problems," Proceedings of the Symposium on Waste Management, Tucson, AZ, March 1975, pp. 57-81.
12Hampstra, J. "Radiotoxic Hazard Measure for Buried Solid Radioactive Wastes," Nuclear Safety, 16 (2), March-April 1975, pp. 180-189.
13Environmental Impact Statement, Nevada Test Site, ERDA-1551, September 1977, pp. 4-17.
14Management of Intermediate Level Radioactive Waste, Oak Ridge National Laboratory, ERDA1553, September 1977.
15Anderson, Terence W., "Radiation Exposures of Hartford Workers: A Critique of the Mancuso, Stewart and Kneale Report," Health Physics, 35, December 1978, pp. 743-750.
16Evans, H. J. et. al., "Radiation-induced chromosome aberrations in nuclear-dockyard workers," Nature, 277, February 15, 1979, pp. 531-534.
17Bond, V. P., "Radiation Standards: Radiological Basis, Development, Characteristics," Testimony before the house Committee on Science and Technology, Subcommittees on Energy Research and Production, and Natural Resources and Environment, June 14, 1979.
18Erickson, L. E., Use of Benefit-Cost Analysis in Establishing Federal Radiation Protection Standards: A Review, PNL-2678, Rauelle, Pacific Northwest Laboratories, August 1979.
19A Perspective on the Radiation Protection Problem and Risk Analysis for the Nuclear Era." IAEA Bulletin, Vol. 20, No. 5, October 1978, p.39.
20Lapp, Ralph E. The Radiation Controversy, Reddy Communications, Greenwich, Connecticut, March 1979.
21Western New York Nuclear Service Center Study TID-28905-2, 1979, p. 4-5 to 4-10.
22Report to the President by the Interagency Review Group on Nuclear Waste Management, TID-29442, March 1979.
23Anthony, 1, N. and H. E. Cline, Fourth International Symposium on Salt, A. It. Cooper (Rd.), Volume I, The Northern Ohio Geological Society, Cleveland, Ohio, 1974.
24Dawson, P. R. and J. R. Tillerson, "Nuclear Waste Canister Thermally Induced Motion," SAND 78-0566, Sandia Laboratories, Albuquerque, NM (June 1978).
25Kerr, Richard A., "Geologic Disposal of Nuclear Wastes: Salt's Lead Is Challenged," Science, 204. May 11, 1979, pp. 603-606.
26Hammond, R. Philip, "Nuclear Wastes and Public Acceptance," American Scientist, 67, March-April 1979, pp. 146-150.
27Cooley, Cad B. and Everett B. Irish, "Status of Technology Related to Radioactive Waste Management and Disposal in Mined Geologic Repositories," In preparation.
28"The Irrational Fight Against Nuclear Power," Time Magazine, September 25, 1978, pp. 7172.
29"Isotopes in Day to Day Life," IAEA Bulletin, Vienna, November 1977.
30"Sewage Sludge Disinfection Using Cesium-137," Sandia Laboratories Bulletin, Albuquerque, NM 1979, pp. 9.