Use of radioactive thermal water after226Ra removal

The paper describes the possibility of efficient and safe use of geothermal water at a location in the town of Zagreb. Geothermal water is used exclusively for the purpose of sport and recreation. Due to elevated²²⁶Ra concentrations, the raw geothermal water must be used in limited proportions so as to exclude any potential health risk for the pool users. With application of adequate treatment methods, such as intense aeration (²²⁶Ra removal efficiency 13.7±3.5%) and filtration of aerated water with high pressure sand filters (removal efficiency 39.5±7.9%), the elevated²²⁶Ra content would be maximally reduced. The decrease of radioactivity enables that the proportion of geothermal water would be increased without any health risk, ensuring great cost reduction spent on the warming of pool waters.