A field study of tritium migration in groundwater

A field study of tritium migration from an underground nuclear explosion was carried out for more than 7 years. A series of satellite wells was drilled around the explosion cavity, which is within a nuclear test site water-supply aquifer. Samples from various wells were analysed. In this way, variations in the tritium concentration of water from different wells were determined, and the extent of tritium migration during the 7 years after the detonation was examined. The maximum tritium concentration reached in water from various wells is just 52-times higher than the maximum permissible concentration for drinking water and decreased afterwards. According to the results obtained, the flow rate of groundwater was inferred to be about 91 m per year and the maximum contamination distance of water supplies by the tritium were < or = 2 km from the explosion cavity.