Recent Developments in the Processing
and Ultimate Disposal of
High-Level Radioactive Waste
WALTER G. BELTER, Sanitary Engineer
Division of Reactor Development, U. S. Atomic Energy Commission
Washington, D. C.
There have been many speculative statements and written materials concerning the impact of radioactive wastes on the development of a nuclear energy industry. Many persons share the view that the effect of this aspect of
the industry is of negligible consequence in comparison to the economic and
technical problems involved in other phases of power reactor technology.
Conversely, however, others believe that safe adequate waste management
might be the major obstacle confronting an orderly and economic growth of
the industry.
Most of the latter concern is based on whether a satisfactory solution to
the problem of ultimate disposal of high activity waste from the reprocessing
of irradiated reactor fuel can be obtained. While there has been an increasing
concern over the problem of high volume, low activity waste and the need for
improved handling and treatment systems for these wastes, the major emphasis in the AEC's waste disposal development program has been directed at the
engineering of practical systems for the ultimate disposal of chemical reprocessing waste. This paper summarizes the AEC's high-level waste problem,
i. e., the types and characteristics of reactor fuel process wastes which are
being handled today and which are anticipated in a nuclear power economy,
high-level waste handling methods which are being used presently, and the
research and development program which is being pursued with the objective
of developing a safe, ultimate disposal system for these wastes.
CHARACTERISTICS OF REACTOR FUEL REPROCESSING WASTE
The chemical processing of irradiated reactor fuels is required to recover
unburned nuclear fuel and transmutation products, such as Plutonium 239 or
Uranium 233, from mixtures of fission products and inert components of the
fuel. Solid fuels, after removal from the reactor and after storage for 90 to
120 days for decay of short-lived fission product activity, are dissolved in nitric acid. The resulting solution is fed to a solvent extraction column (normally containing tributyl phosphate in a hydrocarbon diluent) which selectively extracts the uranium and plutonium. The resulting waste, containing
more than 99.9 per cent of the total fission products, is typified in Table I.
(2). As noted in Table I and Table II, the wastes are mainly solutions of fission products in nitric acid with trace constituents of corrosion products such
as iron, nickel, and chromium, and having radioactivity concentrations from
approximately 80 to 5, 000 curies per gal.
PRESENT HIGH-LEVEL WASTE HANDLING METHODS
Because of the high radioactivity concentrations noted,   it has not been
possible to discharge high level liquid waste into any part of man's environment.     These  wastes  have  been stored   at each of three generating sites.
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