Radiotoxicity of Actinides During Transmutation in Final Stage of Atomic Power

Characteristics of a transmutation mode in final stage of atomic power are analyzed. In this stage, transmutation of actinides accumulated in transmutation reactors is performed without feed by actinides from other reactors. The radiotoxicity during first 20 years of transmutation is caused mainly by ²⁴⁴Cm. During following period of time, ²⁵²Cf is main nuclide. Contribution of ²⁴⁶Cm and ²⁵⁰Cf is 5–7 times less than that of ²⁵²Cf. During 50 years of a transmutation, the total radiotoxicity falls by 50 times. Long-lived radiotoxicity decreases slowly. During the period between T = 50 years and T = 100 years, long-lived radiotoxicity falls by 3.7 times. For each following 50 years after this period, long-lived radiotoxicity falls by 3.2 times. These results corresponding to neutron flux density 10¹⁴ neutr/(cm²s) in transmutation reactor demonstrate that the final stage of a transmutation should be performed with use of high flux transmutation facilities which provide shorter time of transmutation.