Addition of Soluble and Insoluble Neutron Absorbers to the Reactor Coolant System of TMI-2

The physical and chemical properties of six elements were studied and combined with cost estimates to determine the feasibility of adding them to the TMI-2 reactor coolant to depress keff to less than or equal to 0.95. Both soluble and insoluble forms of the elements B, Cd, Gd, Li, Sm, and Eu were examined. Criticality calculations were performed by Oak Ridge National Laboratory to determine the absorber concentration required to meet the 0.95 keff criterion. The conclusion reached is that all elements with the exception of boron have overriding disadvantages which preclude their use in the reactor.