High (e.g., 0.1 to 0.5M.) concentrations of EDTA, HEDTA, and other organic complexing agents are present in some of the nuclear waste solutions currently stored at the U. S. Department of Energy Hanford Reservation in Southeastern Washington State. Ozonation of these alkaline solutions smoothly and efficiently destroys the organic material thereby facilitating ion exchange removal of 90sr and other long-lived cationic radionuclides. Successful benchscale ozonation tests have been performed with both synthetic and actual waste liquids.