Conditioning of unknown spent radioactive sources stored in miserable conditions

Three spent sealed radiation sources (spent SRS), with deformed containers, have been conditioned in 200 liter metallic drum surrounded with metallic layer. The space between the drum and inside layer is filled by concrete paste with Barit sand to decrease the radiation exposure rate to limit that it can safe handle the conditioned sources. The first unknown radioactive spent source was 60Co and the last two radioactive spent sources were 137Cs. After conditioning the results of exposure rate shown that 60Co drum has 250 nSv/h (the B.G for the zone was around between 100-150 nSv/h), i.e., the exposure rate decreased 320 times, while 28 μSv/h for 137Gs drum, i.e., it decreased 21.5 times only. (author)