<p>Plutonium bearing salt residues from electrorefining present a challenge to gamma-ray nondestructive assay due to the possible presence of heterogeneities and the fresh separation of elemental species. Benchmarked Monte Carlo models of these measurements were used to determine the minimum detectable amount of ²³⁵U in the salts, which was found to be above the minimum reportable quantity for all masses simulated. The simulations were also used to develop two FRAM parameter sets, which are used to determine isotopics and effective specific power. Both exhibited minimal bias in specific power with the heterogeneous set improving on previous analysis of salt residues.</p>