Using 131I as a tracer to determine the leakage of Naufu dam in Haizi reservoir

It is a successful method to use radioisotope tracer technique for detecting the leakage of a dam. The authors have applied 131I as the tracer in many bore-holes around Nanfu dam of Haizi reservoir in Beijing, to detect the leakage. The isotope tracer flow meters had been used to detect the direction and velocity of underground water flow in the boeholes at the depths of 20-90 meters. A main leakage passage-way under the dam was confirmed by the detection, thus providing a scientific basis for reinforcing the dam