The Hallam nuclear power plant was located about 25 miles southwest of Lincoln, Nebraska. It was part of the Atomic Energy Commission’s Reactor Power Demonstration Program. The plant operated for 15 months. During this time, it generated about 192.5 million kilowatt-hours of electricity and ran for 6,271 hours before technical problems led to its closure.
In January 1962, the plant reached dry criticality, confirming the reactor core’s physics calculations. By July 1963, Hallam was operating at full power. In September 1964, defects were found in the reactor’s moderator elements, which led to a shutdown. The cost to repair the plant was considered too high, and it did not resume power generation. The plant showed that sodium-cooled reactors could produce steam for electricity and demonstrated the thermal properties of liquid sodium as a coolant.
Decommissioning the Hallam plant was a detailed process, as described in the June 1970 issue of Nuclear News. In August 1966, the Atomic Energy Commission told the Consumers Public Power District, the plant’s operator, to begin retirement procedures. The process included seven main steps, such as removing all nuclear fuel and bulk sodium, treating leftover sodium, managing radioactive residues, and cleaning plant components. Measures were taken to prevent contamination and unauthorized access, including sealing and isolating the reactor vessel and related systems…