Determining criteria for the disposal of iodine-129

The basic consideration in the disposal of the /sup 129/I produced by the nuclear power industry is that humans must be protected from unacceptable radiation risks. Existing standards prescribe maximum concentrations in air and water and, more recently, a maximum release per unit of electrical power production. The global quantity, distribution, and rate of movement of /sup 127/I (natural iodine), naturally produced /sup 129/I, and anthropogenic /sup 129/I are examined. The /sup 129/I released earlier as a result of nuclear activities over the past few decades is not uniformly dispersed. But the possibility of much greater dispersion exists and, therefore, of much greater dilution than was previously attempted. The potential for dilution with respect to either the /sup 129/I concentration or the /sup 129/I//sup 127/I ratio far exceeds the minimum required for acceptable exposure to mankind. For utilizing the dilution principle, it is preferable to package and dispose of /sup 129/I separately from other fission products. The deep ocean is seen to be the logical location for ultimate disposal. A set of 14 basic items is described that can be used to set criteria for storage and disposal of /sup 129/I. It is suggested that preliminary standards be developed onmore » these and perhaps other items to apply to (1) temporary storage and transportation, (2) disposal to a dry environment with a time limitation on calculated behavior, and (3) disposal to the deep ocean with complete release permitted in 10/sup 3/ yr. Early quantification of some of these items will permit better decisions on further research and development needed for iodine removal or control, fixation, and disposal.« less