USE OF RADIOACTIVE THERMAL WATER AFTER RA-226 REMOVAL

The paper describes the possibility of efficient and safe use of geoth ermal water at a location in the town of Zagreb. Geothermal water is u sed exclusively for the purpose of sport and recreation. Due to elevat ed Ra-226 concentrations, the raw geothermal water must be used in lim ited proportions so as to exclude any potential health risk for the po ol users. With application of adequate treatment methods, such as inte nse aeration (Ra-226 removal efficiency 13.7 +/- 3.5%) and filtration of aerated water with high pressure sand filters (removal efficiency 3 9.5 +/- 7.9%), the elevated Ra-226 content would be maximally reduced. The decrease of radioactivity enables that the proportion of geotherm al water would be increased without any health risk, ensuring great co st reduction spent on the warming of pool waters.