This technical report described the formulation of a set of two-group neutron diffusion equations and the solution for the critical fuel cross section in a one-dimensional, multi-region spherical reactor. A subsequent report will describe the ORACLE code developed for survey calculations using this method.

General considerations involving the transportation of irradiated fuel and radioactive wastes are reviewed. It is assumed that many reactors will supply feed to a few large multipurpose chemical plants which ultimately send radioactive waste to a few disposal sites. General economic considerations of irradiated fuel reprocessing, economic aspects of the nuclear economy complex, growth predictions of the nuclear power economy in the U.S., general requirements for the shipment of fuel and waste, regulations applicable to fuel shipment, and permissible radiation levels are discussed.

Preliminary results of tests wit the Westinghouse 100A pump indicate that Al2)3 and tungsten carbide coated bearing-journal assemblies prepared by the Linde process are not promising as substitutes for the graphitar-stellite combination. The front Al2O3 assembly failed at start-up with water and both front and rear tungsten carbide assemblies failed after 121 hours with water at 245 C.

The operation of the HRT mockup was on 0.042m UO2SO4, 0.024m H2SO4, and 0.005m CuSO4 at 280 C and 1400 psi pressure. with the O2 content at near 500 ppm. The pump showed bearing wear and high corrosion. The letdown heat exchanger was removed from the mockup and sectioned. The metallographic examination revealed corrosion. Results of corrosion runs on Ti, zircaloy-2, and stainless steel are given.

The leak detector system consists of one gas pressurized reservoir containing heavy water, a tubing manifold connecting the pressurizer to six separate lines each connected to one of the flanges, tubing lines leading from the second hole on each of three flange pairs (dome and heat exchanger flanges) back into the instrument room, plus required valves and fittings. A schematic diagram of the system in included.

Stress corrosion was found in 8 components of the HRT mockup; only of four of these actually shut down the loop. All of the failures have occurred in the high-pressure system of the loop.

Calculations indicate that it is impossible, even at high oxygen injection rates, to insure an excess of oxygen in the HRT fuel solution if the bubble letdown rate is more than 1 or 2 liters per minute. If, on the other hand, no bubbles are allowed to form, a reasonable excess oxygen concentration can be maintained with an oxygen injection rate which would not tax the capacity of the off-gas system. The xenon poison will be reduced to less than 2% by liquid letdown alone, and if an iodine absorption bed is installed below the catalytic recombiner, the xenon poison should be less than 1% without any bubble letdown. Therefore, it is recommended that sufficient copper be added to prevent the formation of gas bubbles and that the oxygen injection rate be limited to a value which would permit adequate holdup times in the present charcoal adsorption beds, assuming this quantity is sufficient to meet corrosion requirements.

Results of previous toroid tests with 28 micro 1600 fired ThO2 spheres are analyzed. Four possible explanations for the essentially zero attack rates are offered and discussed: peculiar motion of toroids or some unknown wall effect; rotational hydrodynamic forces cushioning the particle impact; the bed was not in suspension and not sliding over the walls of the toroid; round particles are not as erosive to oxide film surface as sharp pointed particles.

During the development of in-reactor corrosion experiments three types of bomb designs have been developed for following quantitatively the consumption of oxygen in a bomb which is fabricated from the particular metal under test. The bombs are designed so as to be rocked continuously during their in-reactor exposure, consequently agitating the uranium salt solution contained in the bomb and permitting gentle movement of the solution past metal specimens and other corroding surfaces. The oxygen pressure is produced within the bomb at the beginning of the run either by the withdrawal of gas from an oxygen tank or by the decomposition of hydrogen peroxide added just prior to closure. Temperature measurements are obtained by mans of thermocouples placed in a well within the bomb body or, in the latest design, there will also be thermocouples staked at several points on the outer wall of the bomb. The assembly is inserted in an experimental access hole in the reactor, brought up to a predetermined operating temperature by means of an electric furnace in close contact with the bomb, and allowed to remain for the desired amount of exposure to reactor radiation. Periodic measurements of temperature and pressure are made and the bomb …