RADIOLOGICAL PROTECTION IN SURFACE AND NEAR-SURFACE DISPOSAL OF SOLID RADIOACTIVE WASTE

This publication provides an update of the recommendations of the International Commission on Radiological Protection for application of the fundamental radiological protection principles for the disposal of radioactive waste in a surface and near-surface disposal facility. The goal of a surface and near-surface disposal system is to provide protection of humans and the environment from the hazards associated with the radioactive waste suitable to the prevailing circumstances. Application of the ICRP System of Radiological Protection for a surface and near-surface disposal facility includes justification of the practice generating the waste, and is considered in the context of a planned exposure situation. The design basis for the facility considers the potential for exposures to humans and the environment associated with its expected evolution, taking into account reasonably foreseeable faults. Optimisation of protection is an iterative, systematic, and transparent evaluation of protective options to reduce the impacts to humans and the environment. Optimisation is essential throughout all life phases, and is of particular importance in the design phase, as this will determine the performance of the facility in the operational and post-closure phases. To deal with the distant future and low-probability scenarios, optimisation has to be complemented by aspects such as robustness, defence in depth, etc. to provide assurance that reasonable steps have been taken to maintain the long-term integrity of the facility. In the case of severe natural disruptive events or human intrusion beyond the design basis, application of the ICRP System of Radiological Protection should be considered with reference to existing exposure situations. Due to the nature of the hazards and associated time scales, the fundamental strategy adopted for the disposal of low- and very-low-level radioactive waste is: to contain and isolate the waste until the short-lived radionuclides have decayed to levels that can no longer give rise to significant exposures; and to limit the activity content of longer-lived radionuclides to ensure that doses and risk are also limited in the long term, when containment and isolation capacities may be diminishing. The successful implementation of this strategy is demonstrated through a structured safety case. The specific options for a surface and near-surface disposal facility will depend upon the particular situation, including the nature of the waste, the local physical environment, and the societal context. Dialogue between the operator, regulator, and stakeholders should be established as early as possible in the process, with the inclusion of ethical values to help contribute to promoting a shared understanding of the application of the ICRP System of Radiological Protection. © 2024 ICRP. Published by SAGE.