MODES OF CS-137 DESORPTION FROM MARINE-SEDIMENTS BY SEA-WATER

Sea water is observed to be a good desorbing agent for Cs-137 from mar ine sediments. Investigations on the sites of Cs-137 binding and their abundance by desorption over extended periods indicated that, whateve r the time of contact of sorption, Cs-137 has three modes of desorptio n: fast component with desorption half-time of 30-50 min, medium compo nent with desorption half-time of 25-50 h and slow component with deso rption half-time of 31-112 days. These are expected to be sites of ion exchange, slower exchange and trapped Cs in the clay mineral layer la ttices.