Decommissioning: Solutions for nuclear plants

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  • Ann. nucl. Energy, Vol. 14, No. 7, pp. 387-388, 1987 0306-4549]87 $3.00+0.00 Printed in Great Britain. Pergamon Journals Ltd

    LETTER TO THE EDITORS

    DECOMMISSIONING: SOLUTIONS FOR NUCLEAR PLANTS

    (Received 26 January 1987)

    The decommissioning of nuclear power plants remains a ignated 30-yr licensing period, decommissioning costs contentious issue. Critics of nuclear power claim that the (again, as a fraction of the cost of total generation) will still need to decommission these facilities constitutes a fiscal time be low. bomb for rate payers and a potential health threat as well. However, a nuclear plant does not have to be decom- A close look at the facts, however, shows that the financial missioned immediately after it is shut down. The note of issue is trivial and the health risk largely irrelevant, urgency that some critics attach to the need for prompt

    Decommissioning refers to the removal from service and decommissioning is unsupported by the facts, and indeed permanent shutting down of any industrial facility when it there are good economic and environmental reasons for wait- is no longer useful. The cost for decommissioning a nuclear ing. First of all, the existence of a nonoperating nuclear plant plant is estimated (in 19845) to be about $100 million, a tiny with its fuel core removed simply does not present any risks fraction of the value of the total power generated by a single to the public, while waiting to dismantle presents significant plant--typically $6 billion. For perspective, the complete advantages in reduced risk for workers. In addition, decon- decommissioning of a coal plant will cost about $25 million, tamination costs are lower because after 10 yr the levels of The cost of decommissioning a nuclear plant is thus not radioactivity at the site decay to about one-fourth of the unique, nor particularly burdensome since a surcharge on original amount, and after 50 yr the radioactivity has decayed electric rates of less than I% would provide more than more than 10-fold. A 50- to 85-yr dormancy period will enough money to cover the costs, allow the radioactive contamination to decay so as to allow

    The assumption implicit in many discussions about unrestricted access. The cost to maintain the site in the decommissioning is that nuclear plants will operate for only interim is estimated to be between 569,000 and $150,000 per 30 yr. The Atomic Energy Act of 1954 dictates that the yr, a tiny fraction of the savings that can be realized by license period begins at the issuance of a construction permit waiting. andmaynotexceed40yr;atthatt imea"bestguess"est imate As for the hazards to the public from the actual dis- of a nuclear plant's useful life based essentially on experience mantlement and disposal of a nuclear power plant, every with fossil fuel plants. Since a nuclear plant takes about 10 scientific analysis has shown them to be miniscule. Once the yr to build, only 30 yr of licensed operation remain after the fuel is removed (the first step in decommissioning and one construction phase is completed. In addition, construction which resembles a typical plant refueling), there is no longer loans and bonds cannot reasonably be issued for repayment a source of volatile or highly radioactive material at the over a much longer period of time. site. Most of the dismantling is done using conventional

    Thus the 30-yr time period is an institutional artifact: techniques since most of the structures are not radioactive. from an engineering standpoint, most of these plants can be (And of course, waiting a number of years will ensure that operated for many more decades. And any extension of the virtually all of the job involves no radioactive material.) life of the plant will result in a greater return on the initial Cutting up the radioactive components and scraping and investment, completely overturning the unfavorable econ- cleaning contaminated surfaces will largely take place inside omics currently projected for some of the costlier units now the existing containment, a building designed to hold much coming on line. This, in turn, will also cause decom- larger quantities of radioactive material under much more missioning costs as a proportion of the total value of the hostile temperatures and pressures than decommissioning plant to plummet, entails. Most of the radioactive materials will find ultimate

    In order to extend the operational life of a nuclear plant, disposal in low-level waste repositories. a utility must refurbish those components necessary to meet According to the Nuclear Regulatory Commission, the federal licensing regulations and apply for an extension of most severe hypothetical accident associated with decom- the original operating license. In engineering circles, it is missioning would result in a radiation dose to an individual becoming widely accepted that the current generation of of less than one percent of the exposure from a chest X-ray, nuclear plants can easily operate for 80 years or more, while an amount equivalent to one-third the average daily natural the operating life of a few of the older units may be limited radiation human beings receive just from living on earth. In by their reactor pressure vessels which are subject to a form terms of human health, such exposure levels are incon- of aging called embrittlement--not an insurmountable prob- sequential. Indeed, radiation exposure for smoke-detector lem, but possibly too costly to repair in smaller nuclear units, sources is arguably more significant.

    Regardless, just as with a car, after a certain amount of In attempting to plan for decommissioning nuclear plants usage the costs of maintenance and the lower reliability of far in advance of the actual need to do so, the nuclear "high-mileage" plants make them uneconomic to operate. It industry has distinguished itself by its farsightedness. Other is widely assumed that some of the 50 existing older plants industries with similar needs make no provisions for decom- with licenses scheduled to expire before year 2015 will not be missioning. For instance, the National Academy of Sciences candidates for life extension. However, even in cases such as noted in a 1985 report that offshore oil platforms will need these where the plant is not likely to operate past the des- to be decommissioned, an exercise which will be costly and

    387

  • 388 Letter to the Editors

    which presents some environmental risks. Leaving the old significant regulatory hurdles for utilities to overcome in and decaying platforms in place without decommissioning engaging in life extension, or in arriving at acceptable them is unlikely to be an environmentally acceptable option, methods for accumulating funds for ultimate decom- posing navigational hazards as well. Moreover, the Academy missioning. However, it is clear from an assessment of the notes that the estimated total cost to decommission the 4000 technical literature both here and abroad, that no credible existing oil platforms, and the 1500 under construction could case can be made for decommissioning as a major financial be $50 billion or more, exceeding the likely cost of decom- or health problem. missioning all of the nation's nuclear power stations. The principal difference, however, is that many of the nuclear Science Concepts Incorporated THEODORE BESMANN power plants will operate for decades longer than the oil 1625 K St N.14/. MARK P. MILLS platforms, thus providing a much greater off-setting econ- Suite 1125 omic benefit to society. Washington D.C. 20006

    This discussion is not meant to suggest that there are no U.S.A.

    Theodore Besmann, a nuclear engineer, is a research group leader at the Oak Ridge National Laboratory and a coauthor of a book on energy policy. Mark Mills, a physicist, is president of Science Concepts, Inc., a Washington D.C.-based research firm, The authors recently completed a report based on a technical

    literature review of decommissioning.

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