EFFlX13 OF ACIINIIIE COMPOSITIONAL VARIABILITY IN THE

l%e partitioning and transmutation concept (P-T) has as a mission the reductio~ by many orders of rnagnitudq of certain undesirable nuclides in the waste streams. Given that only a very small fiction of spent fiel can be “rejected” by a P-T enterp~ a P-T system must therefore be capable of accommodating a wide range of spent fuel characteristics. Variability of nuclide composition (i.e. the feed material for transmutation devices) may be important because virtually all transmutation systems propose to configure TRU nuclides remvered from discharged LWR fuel in critical or near-critical cores. To dat% all transmutation system core analyses assume nonvariable nuclide concentrations for startup and recycle cores. Using the Department of Energy’s (DOES) Characteristic Data Base (CDB) and the 0RIGEN2 computer wd~ the current and projected spent fuel discharges until the year 2016 have been categorized aczordmg to combinations of fuel bumup, initial enrichmen~ fuel age (cooling time) and reactor type (boiling-water or pressurized-water ractor). In addition to quantify@g the Variabtity of nuclide composition in current and projected LWR fuel discharge, the variabtity of the infinite multiplication fiwtor (IQ is calculated for both fast (ALMR) and thermal (accelerator-based) transmutersystems. It is shmwt that actinide compositional variations are potentially significant and warrant further investigation.