Determination of volume of water reservoir by using tritium concentrations

Water supply, especially in urban areas, is one of the most important issues all over the world. Tritium (3H or T) as a natural radioactive isotope of hydrogen with a half-life (T1/2) of 12.26 years has been accepted as an efficient tool in groundwater hydrology. By using an appropriate model, relevant hydro meteorological and isotope data, a computer program which implements an adequate recursive equation, the volume of the reservoir under the Galicica Mountain that recharges the St. Naum, Spring as well as the Mean Residence Time (MRT) of the ground water has been determined and the respective values are V=3.7 x 10(9) m(3) and MRT= 6 years.