Friday, July 4, 2008

Production of Plutonium in commercial reactors -- a review of the literature from the past half century

July 4th, 2008

Dear Readers,

Let's BBQ! More specifically, let's BBQ ourselves from the inside with radioactive particles.

And let's refute the hollow assertions made by the new spokeswoman for San Diego Gas & Electric, who made the following specious and false claims to an activist recently (and no doubt makes them to media throughout Southern California, as well):

"San Onofre does not produce plutonium."

"San Onofre does not emit any radioactive waste."

So: Do commercial nuclear reactors produce plutonium? And do they emit radioactive waste?

Yes, and yes. They all do. Let's concentrate on plutonium production, and consider the evidence from decades' worth of literature.

All U.S. commercial reactors are Light Water Reactors (LWRs). About 70% are Pressurized Water Reactors (PWRs). The rest are Boiling Water Reactors (BWRs).

First up: From a very popular nuclear physics textbook from the mid 1950's, the figure of 0.46 pounds per ton per year is given for the conversion of U-235 to Pu-239 in the Brookhaven reactor (a small early research reactor on Long Island, NY). An equal amount of (radioactive) fission products were also produced (1).

In 1974, The Ubiquitous Atom described the formation of plutonium in the Radiation Laboratory, Berkeley, California, in March, 1940: "This element, unknown to nature, was formed by uranium 238 capturing a neutron, and thence undergoing two successive changes in atomic structure with the emission of beta particles" (2).

In Edward Teller's 1979 book, the father of the H-Bomb describes a "provocative series of articles in The New Yorker" from December 1973 which discussed: "nuclear sabotage, and the possibility that plutonium produced by nuclear reactors might be stolen and used to construct a homemade nuclear explosive. With the continuing prevalence of terrorism, these dangers should not be disregarded" (3).

From No Nukes: Everyone's Guide to Nuclear Power (1979): "The average commercial reactor sold today produces around 500 pounds of plutonium each year. The bomb that destroyed Nagasaki was made with 10 pounds of plutonium -- one fiftieth of the yearly output" (4).

According to Plutonium, Power, and Politics (1979), reactor fuel for LWRs starts at "about 3 percent U-235 and 97 percent U-238. After its full residence in the core (about three years for a PWR, four for a BWR), the spent fuel consists (by mass) of about 95 percent U-238, 1 percent plutonium, 1 percent residual U-235, and about 3 percent light elements produced by fission of uranium and plutonium" (5).

Nuclear Power in Crises (1989), noted: "The purpose of reprocessing is to separate unburned uranium and other potential fuel isotopes, like plutonium, from the useless by-products of the fission process: in theory this maximizes the energy value of the fuel and minimizes the residues of highly radioactive waste. Unfortunately, the technology is difficult and dangerous, especially for the treatment of thermal oxide fuels used in light water reactors (Bunyard, 1981), and few countries have been willing to persist with its development." The book notes that "even" the U.S.A. had, at the time, abandoned reprocessing (6). The U.S.A. still does not reprocess spent fuel.

Caldicott points out in If You Love This Planet (1992) that: "Wherever the world's nuclear power plants are located, radioactive wastes are discharged into seas, rivers, or lakes. All reactors need thousands of gallons a day for cooling, and this water is routinely flushed back into the water system, inevitably polluted with radioactive elements" (7).

Megawatts and Megatons (2002), states that at the reprocessing plant at La Hague, France (operated by AREVA): "The spent fuel from low-enriched uranium contains about 1% plutonium -- about 200 kg to 250 kg from the annual download of 20 to 25 tons from each reactor" (8). French reactors are almost exclusively PWRs.

Clearly, the spokesperson for SDG&E is intentionally misspeaking. Perhaps it is because she knows that: "Statements made by the public affairs officers of a NRC licensee are not regulated activities. Therefore, the veracity of such statements will not be investigated by the NRC" (9).

Sincerely,

Ace Hoffman
Carlsbad, CA

The author, an award-winning educational software developer, has studied nuclear issues for more than 35 years.


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References:
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(1) Principles of Nuclear Reactor Engineering, Samuel Glasstone, Consultant, US Atomic Energy Commission (with assistance from staff members of Oak Ridge National Laboratories) Foreword by Lewis L. Strauss, Chairman, USAEC, D. Van Norstrand & Co, New Jersey, 4th Edition, Sept., 1956, pages 396-399.

"Assuming a conversion efficiency of uranium-235 to plutonium-239 of 100 per cent . . . after one full year of operation of the Brookhaven reactor is . . . approximately 23 lb [of plutonium]. The small quantity of plutonium destroyed by fission and nonfission capture reactions may be neglected. The composition of the spent fuel will thus be roughly as follows:

Uranium (all isotopes): 99.954%
Plutonium-239: 0.023%
Fission products: 0.023%

These figures are given to provide some idea of the magnitude of the problem involved in the recovery and purification of fertile and fissionable materials in the processing of spent reactor fuel. Each ton of such fuel, according to the foregoing considerations, will contain about 0.46 lb of plutonium, 0.46 lb of fission products, and just over 1999 lb of uranium. The proportion of uranium-235 in the latter will have been reduced from the normal value of 0.71 to slightly over 0.68 per cent, partly by fission and partly by conversion to uranium-236 as a result of neutron capture."

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(2) The Ubiquitous Atom, Grace Marmor Spruch and Larry Spruch, "Based upon material from booklets in the series "Understanding the atom, produced under the aegis of the United States Atomic Energy Commission." Charles Scribner's Sons, New York, 1974, Page 281.

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(3) Energy from Heaven and Earth, Edward Teller, W. H. Freeman & Co., San Francisco, 1979, page 192.
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(4) No Nukes: Everyone's Guide to Nuclear Power, Anna Gyorgy & Friends, South End Press, Boston, MA, 1979, page 301

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(5) Plutonium, Power, and Politics: International Arrangements for the Disposition of Spent Nuclear Fuel, Gene I. Rochlin, University of California Press, 1979, page 83. The quote continues: "There are also small amounts of other heavy elements, particularly neptunium, americium, and curium, that are produced by a complex series of neutron absorptions and radioactive decays." On page 79 it states: "There is no doubt that throughout the twenty-plus-year history of commercial nuclear power, and the twenty year history of the dissemination of the technology for fuel reprocessing, it has been the assumption of nuclear industry and nuclear agencies alike that spent reactor fuel would be reprocessed . . . Alternatives to reprocessing for the disposition of spent fuel were never given serious consideration." On page 86 it points out that a "uranium-only recycle would provide no economic incentive to reprocess spent fuel at this time." To be economically viable, the plutonium must also be recovered.

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(6) Nuclear Power in Crises: Politics and Planning for the Nuclear State, Edited by Andrew Blowers and David Pepper, Nichols Publ. Co., New York, 1987, page 69.

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(7) If You Love This Planet: A Plan to Heal The Earth, Helen Caldicott, M. D., W. W. Norton & Co., New York, 1992, page 87.

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(8) Megawatts and Megatons: The Future of Nuclear Power and Nuclear Weapons, by Richard L. Garwin and Georges Charpak, University of Chicago Press, 2001, 2002, page 136.

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(9) Letter to the author from the Nuclear Regulatory Commission, received following a complaint about the spokesperson for Southern California Edison (SCE) lying intentionally (2001).

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