Thermodynamic Modeling of 90Sr Migration with Alkaline Groundwater at the Chornobyl NPP Industrial Site

Thermodynamic modeling of monitoring studies on well 4-G, which was located on the industrial site of the Chernobyl nuclear power plant, was performed. In the range of pH 9.5–12.5, an increase in the concentration of strontium in the form of SrOH+ and a decrease in the form of Sr2+ was noted in the groundwater, against the background of an increase in the volumetric activity of 90Sr by 200–500 times to 550 Bq/l. The reason for this was an increase in the ionic strength of solutions >5 mmol/l.