Migration of Radionuclides (60Co, 85Sr and 137Cs) in Alkaline Solution (pH 12) through Sandy Soil Layer

Column experiments have been carried out on the migration of ⁶⁰Co, ⁸⁵Sr and ¹³⁷Cs in an alkaline solution (pH 12) through a sandy soil layer. Radionuclide--concentration distributions in both an effluent and a sandy soil layer were measured after pouring 200ml of aqueous solution containing the radionuclides on the layer, followed by eluting with 3,800 ml of distilled water.

Strontium-85 and ¹³⁷Cs gave a similar distribution pattern in the soil layer, while ⁶⁰Co migrated deeper into the layer. The migration velocity followed the order; ⁶⁰Co>⁸⁵Sr≧¹³⁷Ca. The order was different from that obtained with the radionuclides existed in a neutral solution. This suggested that the migration behavior of the radionuclides is significantly affected by the pH of the solution in which the radionuclides exist.

The sandy soil layer used here is considered as a linear system for the migration of in the solution of pH 12.