Los Alamos National Laboratory Report LA-1648

The proposed Los Alamos Omega West Reactor is designed to be a research tool delivering a maximum neutron flux of approximately 5 x 10/sup 13/ n/sec/cm/ sup 2/ at its maximum operation power level of 5 megawatts. Solid fuel elements of the type developed for the Materials Testing Reactor will be utilized. Cooling will be accomplished with circulating demineralized water and evaporative coolers. Experimental facilities will include numerous horizontal ports, two of which will incorporate built-in rotary beam shutters, and a thermal column. If all the radioactive material contained in the fuel elements during normal reactor operation were to become spread through the residential area of Los Alamos, persons in some parts of the city would be exposed to greater than lethal doses. It does not appear that known mechanisms could operate to produce this situation. Because of geographical relationships and low ground-water flow velocities, there seems to be no likelihood of water supply contamination in the event of a reactor disaster. Care has been taken in the reactor design to insure against sudden draining of the main reactor tank containing the fuel assembly, as such a sudden loss in cooling might lead to damage of the fuel elements. Conservative estimates indicate that the reactor shielding is adequate for the protection of the operating personnel