Management of Commercially Generated Radioactive Waste - U.S. ...

4.13
the radioactivity in spent fuel while predisposal operations take place. Tables in Appen-
dix A of Volume 2 provide data for these and other radionuclides for longer time periods.
Substantial quantities of non-TRU wastes are generated in the once-through fuel cycle
during operation of nuclear power plants and spent fuel storage facilities. Depending on
the treatment in the once-through fuel cycle, substantial amounts of TRU secondary wastes
may or may not be produced. If the treatment mode involves simply the packaging of intact
spent fuel, the secondary waste produced in the packaging operation should contain very lit-
tle TRU radioactivity and is considered here to be all non-TRU waste. However, if the spent
fuel cladding is breached in the treatment process, then secondary TRU wastes would be pro-
duced. Depending on the complexity of such a process, substantial amounts of TRU secondary
waste could be produced. The secondary TRU wastes from the once-through fuel cycle would
be similar to some of the primary wastes in the reprocessing case.
4.2.2 Reprocessing Cycle
When spent fuel is processed to recover (for recycle) the uranium and plutonium it con-
tains, primary TRU wastes of two types are generated in recycle facilities: 1) fuel repro-
cessing plant (FRP) wastes and 2) mixed oxide fuel fabrication plant (MOX-FFP) wastes. In
fuel reprocessing plants the spent fuel is dissolved out of the cladding, the uranium and
plutonium are recovered and purified by a series of solvent extraction operations, and the
uranium and plutonium products are converted to UF 6 and Pu02 (or mixed U0 2 -Pu02) for further
use. In mixed oxide fuel fabrication plants the PuO 2 (or mixed U0 2 -Pu02) is blended with
U0 2 , processed to a suitable form, and incorporated into mixed oxide (MOX) fuel elements to
be recycled to a nuclear power plant. More extensive descriptions of such facilities are pre-
sented in DOE/ET-0028 (Section 3.2).
Table 4.2.3 contains the estimated quantities and selected radionuclide contents of the
primary high-level, TRU, and gaseous wastes generated in the reprocessing cycle. The radionuclide
contents are given as fractions of the amounts present in the recycle spent fuel for
the FRP wastes and as fractions of the amounts present in the fabricated MOX fuel for the
MOX FFP wastes. These amounts are presented in Table 4.2.4, for an example recycle spent
fuel, and in Table 4.2.5, for an example MOX fuel. Except for the isotopes of uranium and
plutonium, the total amounts of radionuclides present in the untreated wastes of the two
fuel cycles may be directly compared using the data of Tables 4.2.2 and 4.2.4. The quanti-
ties of uranium and plutonium in the reprocessing cycle wastes amount to about 1% of that
present in the spent fuel.
Wastes from two areas of the fuel reprocessing plant (the fuel storage basin and the
uranium conversion facility) are classified as non-TRU wastes. As in the once-through
cycle, non-TRU wastes also result from operation of nuclear power plants and spent fuel
storage facilities.