Special Inquiry into the U.S. Nuclear Regulatory Commission's Oversight of Research and Test Reactors (OIG Case No. I2100162)

The Office of the Inspector General (OIG) initiated this Special Inquiry following a radioactive release to the environment from the National Institute of Standards and Technology (NIST) test reactor located in Gaithersburg, Maryland on February 3, 2021. After the release, the NIST test reactor was shut down for more than two years before receiving authorization to restart from the U.S. Nuclear Regulatory Commission (NRC). This NIST event was one of eight unscheduled incidents or events in fiscal year 2021 that the NRC determined to be significant to public health or safety.This Special Inquiry’s focus broadened from the 2021 NIST event to include consideration of the NRC’s oversight of other Research and Test Reactor (RTR) facilities to assess potential systemic issues. However, this report primarily discusses the NRC’s oversight of the NIST test reactor prior to the February 2021 event because the event highlights areas in which the agency’s oversight could be improved as it relates to other smaller nuclear facilities.