Year
2019
Abstract
Research reactors are used to produce isotopes for medical, industrial and research purposes. However, research reactors can also produce special fissionable material, such as plutonium and U-233, which can ultimately be used to produce a nuclear device. The International Atomic Energy Agency (IAEA) is the global entity that implements safeguards to detect clandestine production, use, or diversion of nuclear material. The IAEA implements robust safeguards across the fuel cycle. However, because research reactors are designed for flexible use and there are hundreds currently in operation, implementing safeguards for such facilities is challenging. One potential way for the IAEA to strengthen safeguards at research reactors is to use “mailbox” declarations, in which the operator regularly (up to daily) provides essential operating information to the IAEA electronically, in combination with short notice random inspections. The three primary proposed parameters for operator reporting to the IAEA through mailbox declarations are operating power and time, fuel temperature, and control rod positions. A State misusing a research reactor to clandestinely irradiate fertile material would be able to manipulate some of these parameters to conceal the misuse, but it would be very difficult to manipulate all of them. If these three parameters are regularly reported to the IAEA, inspectors would be able to use these data to identify facilities for short notice random inspections. This paper will use calculations, completed via Monte Carlo N-Particle (MCNP) radiation transport code, to investigate the illicit production of plutonium in a research reactor. It will discuss lengths of time needed to irradiate material, as well as the resulting effects on the recorded operating time and power, fuel temperature, and control rod placement.