Penetration of tritium into ground water in the Czech Republic

Tritium (3H), the radioactive hydrogen, can form naturally by interaction of the cosmic radiation with the atmosphere, or it can be produced by human activities. In recent, tritium occurs distributed in environment in low concentrations, which means no significant health risk, but it can be used for tracing purposes. In the Czech Republic, tritium was monitored in ground water samples together with the samples of precipitation, using the method of liquid scintillation analysis with electrolytic enrichment. The average value of the tritium concentration in ground water was 0.57 Bq/l, which is lower than the average value evaluated for precipitation (0.97 Bq/l). This is caused by the radioactive decay of tritium in ground water, where the connection with the surface is limited. The results of this tritium monitoring can be used for estimation of the surface influence onto the ground water and for the assessment of ground water vulnerability.