Efficiently planning a decontamination and decommissioning (D&D) operation at a nuclear facility requires detailed information on the conditions present. In the wake of a disaster, or just years of abandonment, a facility’s layout may have dramatically changed, making previous facility drawings unreliable, and radioactive particles may have been spread over the site, contaminating equipment and structures. Rather than tasking workers with mapping and characterizing the contamination, which can take days or weeks and poses a health and safety risk to the workers, mapping the site and locating contamination can be done remotely by an unmanned aerial vehicle (UAV), which would reduce the time it takes to gather this essential information and mitigate risks posed by hazards of uncertainty. We have developed a system to generate a 3-D map of a facility, highlight the locations of all contamination and identify the radioisotopes present, using a compact, semiconductor gamma-ray detector, a laser-based range scanner, and a versatile hex-rotor UAV to host the system. Testing showed that this setup was able to generate a map of a large room and locate the positions of test sources that were placed within it. Using the same computer code and base equipment, a larger detector and longer range laser sensor would greatly increase the speed at which the radiological map is generated, allowing larger rooms or facilities to be mapped as well
