COMPLETE DOCUMENT (1862 kb) - OECD Nuclear Energy Agency

The main conclusions of these US reports are:
• the toxicity of high-level waste during the first thousand years cannot be reduced by
transmutation since the cross-sections of the isotopes 90 Sr, 137 Cs, 3 H and 85 Kr are too
small;
• the cost of alternative reprocessing in order to reduce the actinide content to a level below
100 nCi/g (3 700 Bq/g) is very high and requires the construction of advanced aqueous
reprocessing facilities and/or the development and construction of pyrochemical
reprocessing units;
• the use of LMRs for burning plutonium and actinides would require the construction of an
aqueous reprocessing capacity of ~2 000 tHM/year and the deployment of 30 GWe LMR
capacity creating a cost penalty of $0.5 billions to $2 billions per year. The spent fuels
from LMRs would be reprocessed in a smaller scale pyrochemical unit which has still to
be developed;
• the decentralised structure of the US electricity production, the absence of economic
incentive for reprocessing and the changes in the regulatory requirements (NRC and EPA)
for disposal facilities make the acceptance of P&T as a waste management scenario very
improbable under the present economic conditions;
• the radiotoxicity of a repository is not accepted as a scientific argument in the assessment
of the risk except in the case of human intrusion.
Only the combined use of 137 Cs – 90 Sr separation and actinide burning followed by a long (300
years) surface storage would alleviate the repository heat problem.
The most recent and most comprehensive assessment report on P&T was issued by the
National Academy of Science of the US under the chairmanship of N.C. Rasmussen [209]. The report is
entitled “Nuclear Wastes: Technologies for Separations and Transmutation” and covers all aspects of
the problem from an American point of view. The principal recommendations listed in the report are:
• none of the P&T system concepts reviewed eliminates the need for geological disposal;
• the current policy of the “once-through-cycle” should be continued;
• fuel retrievability should be extended to ~100 years;
• R&D should be conducted on selected topics of P&T.
In France, a National Evaluation Commission was appointed in 1993 in order to supervise the
R&D activities in the field of radioactive waste management. Reports were issued [210-212] in 1995,
1996 and 1997. In the field of P&T, the following recommendations were made:
• priority should be given to separation of Am-Cm from rare earths followed by Am/Cm
separation;
• among the fission products priority should be given to Cs and Tc;
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