EPITHERMAL-THERMAL Pu-Th AND ²³³U-U REACTOR SYSTEMS.

A symbiotic system of Pu-Th- and **2**3**3U-U-fueled reactors has been proposed and analyzed. These two reactor systems are investigated in this paper. The first system, denoted as system A, is composed of 3. 58 reactors of the PWR type, fueled with **2**3**3U-**2**3**5U-**2**3**8U fuel, and one tight lattice reactor (V//M/V//F equals 0. 4), fueled with Pu-Th. The second system, denoted as system B, is composed of 2. 86 reactors of the PWR type and one tight lattice reactor (V//M/V//F equals 1. 0), fueled with Pu-Th. Both reactor types are supposed to rely heavily on current PWR technology; subsequently, the investments needed for development are not expected to be high. Furthermore, similarity to the current PWR might simplify their regulatory procedures.