After graduating Washington State University in 1950, Carl Higby was recruited to work at Hanford as an operations supervisor for the reactors. Higby discusses some of the problems that arose when the reactor was online, and explains how impurities in the coolant water could plug some of the sensor tubes and force them to shut the reactor down. Higby also discusses the innovation of the Ball-3X System, a safety method that included a hopper of small boron steel balls that would be dropped into the reactor and fill up the vertical rod safety channel, shutting the reactor down and preventing a critical meltdown.
Roger Rohrbacher arrived in Hanford in early 1944, where he worked as an instrument engineer at B Reactor. Rohrbacher was tasked with measuring neutron flow and temperature pressure and radiation monitoring. He gives a detailed account of how the reactor functioned and explains specific safety measures in place to prevent a nuclear meltdown. He also discusses many of the early problems that scientists faced during the early days of B Reactor and explains innovations that workers came up with to solve these problems. Rohrbacher explains the secrecy and security that surrounded the project at Hanford and how it affected his work.