This is the monthly report for the Hanford Laboratories Operation, February, 1959. Reactor fuels, chemistry, dosimetry, separation processes, reactor technology, financial activities, biology operation, physics and instrumentation research, employee relations, operations research and synthesis operation, programming, radiation protection operation, and laboratories auxiliaries operation area discussed.

Plutonium Oxide Fuels. Mixtures of PWR grade UO2 containing 10, 20, 30, 40, 50, and 60 w/o PuO2 were sintered in hydrogen for 44 hours at 1600 C to get additional data on solubility in this system. Densities of all the pieces were low, approximately 80 percent of theoretical; however, solid solution formation was complete in every case. The low density material should not affect lattice parameter values, but it did slightly reduce the intensity of the reflections.