Fixation of Atomic Wastes in
Inert Solid Materials
ERIC B. FOWLER, Acting Group Leader
H-7 Health Division
Los Alamos Scientific Laboratory
Los Alamos, New Mexico
INTRODUCTION
A relatively efficient solution to many of the problems associated with the
disposal of low-level radio-active wastes occurred at an early date in the history
of the Atomic Energy Industry. Such wastes represent minor radiation hazards and
can be treated with conventional equipment. One such treatment plant is the new
$2 million facility located at the Los Alamos Scientific Laboratory, Los Alamos,
New Mexico, which uses chemical precipitation for alpha removal and ion exchange for beta-gamma control. The processes are very similar to standard water
treatment methods, and equipment is identical to that of standard water and
sewage treatment plants.
In contra-distinction, the problems associated with the disposal of high-level
wastes which arise from the plutonium production industry and from the processing
of spent reactor fuel elements are largely unsolved at this date. This paper will
review some of the approaches to these problems and the present status of the science of fixation of high-level atomic wastes in inert, solid materials.
The principal problem associated with the disposal of a high-level waste is
due directly or indirectly to the intense radiation encountered. Other problems
are related to the half-lives of the radionuclides present and to the corrosive nature of many of these wastes.
The magnitude of the problem is best illustrated by data relative to the volumes of wastes and associated radioactivities currently being produced. High
levels of radioactivity are created when uranium, enriched uranium, or plutonium
are used as fuels in nuclear reactors. A typical power reactor operating at 100
electrical megawatts for 10 days will produce about 11 lbs of fission products, or
about the same amount as produced by a 100 kiloton atomic weapon.
Reactors burn fuel just as do all other types of energy-producing machines.
However, in the case of a reactor the end-products are radioactive fission products
from the parent element.
When the spent fuel elements are removed from the reactor, they are usually
stored at the reactor site until the short-lived radioisotopes have decayed to a
point where the fuel elements can be processed for the recovery of useable fuel.
In the case of a 150 electrical megawatt plant, the radioactivity from the stored
fuel elements of only 1/3 of the core may contain an average of 30, 000, 000
curies of radioactivity. These fuel elements would generate about 100 thermal
kilowatts of energy during a six-month storage period.
The radiation and thermal data indicate the problems encountered for short-
term storage of these elements and for ultimate disposal of the wastes which later
arise from their processing.    It is significant to note that most of the man-made
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