> Following the accident, it was determined that eight RTGs [radioisotope thermoelectric generator] of the Beta M type had been brought into Georgia in the early 1980s to serve the radio relay system between the Engury hydroelectric station and Hudoni hydroelectric station, which was under construction at the time. These generators were placed in pairs at four substations located in areas where there were no other means of electrical power supply. In these generators, the heat generating elements were 90Sr radioisotope sources with an activity of 1480 TBq and a heat power of 250 W.

> After the construction of the Hudoni hydroelectric station was stopped, the radio relay system lost its function, and the generators were left without supervision and control. By the end of the 1990s, the generators were disassembled, with the radioactive sources exposed and removed from their original location. Of the eight 90Sr radioactive sources, only six have so far been found.