Two methods for evaluating the effects of nonuniformities in reactor fuel on resonance integrals are described. In the first method, the volume and the surface effects on the resonance integral are separated by dividing the rod into two homogenized regions and a general formalism is developed which is adequate for numerical computation. In the second method, which uses the moment technique of Cady and Clark, a generalization of the Nordheim equation, available for the study of any nonuniformity of the rod is presented. As an example, an analytical expression for a uniform temperature equivalent to a parabolic distribution is given.