Year
2014
Abstract
A radioisotope thermoelectric generator (RTG) is an electric power source that uses heat generated in the course of the natural decay of radioactive isotopes and transforms it into electric power through thermoelectric converters. By the end of the twentieth century approximately one thousand RTGs containing radioactive heat sources based on strontium-90 had been manufactured and commissioned in Russia for application as power sources in remote locations such as lighthouses and navigational beacons. Most of these RTGs designed for autonomous operation were installed at unguarded sites. In the 2000s the U.S. and Russia identified that there was a risk of unauthorized activities aimed at RTGs and possible negative consequences if a terrorist attack involved the use of the radioactive sources from these devices. Recognizing the risk posed by the unattended operation of RTGs, authorized Russian organizations including NRC “Kurchatov Institute” worked with DOE/NNSA’s Global Threat Reduction Initiative (GTRI) and multiple national laboratories to address this issue. Since 2002, Russian specialists and U.S. teams supported by Lawrence Livermore National Laboratory, Nevada National Security Site, Sandia National Laboratory, and Oak Ridge National Laboratory have been successfully implementing the joint program aimed at removing the RTGs from their locations in the field, gathering the recovered RTGs at temporary storage sites guarded and equipped with physical protection systems, delivering the RTGs to Rosatom enterprises for disassembly and extraction of the radioactive heat sources, and placing the strontium-90 sources in long-term storage at “Mayak” Production Association. Over the past decade of this Russian-American cooperation a considerable scope of work has been performed: 482 RTGs with a total activity of more than 20 million curies have been recovered. As a result, the potential radiological threat posed by these RTGs was eliminated in the Baltic Region, the Far East, and along the Northern Sea Route. Additionally, hundreds of alternative power sources (APS) that run on solar energy were purchased to replace the recovered RTGs. More than 200 of these APS units have already been put into place and the remaining ones will be installed in the future.