Environmental issues in the geological disposal of carbon dioxide and radioactive waste

A comparative assessment of the post-closure environmental issues for the geological disposal of carbon dioxide (CO2) and radioactive waste is made in this chapter. Several criteria are used: the characteristics of radioactive waste and CO2; their potential environmental impacts; an assessment of the hazards arising from radioactive waste and CO2; and monitoring of their environmental impacts. There are several differences in the way that the long term safety of the disposal of radioactive waste and CO2 is regulated and evaluated. While the regulatory procedures relating to the development of a facility for the disposal of radioactive waste in many countries with nuclear power programmes are well defined having evolved over several decades, those relating to CO2 disposal are less well developed. The results of this assessment show that, despite key differences, many of the approaches addressing environmental issues are similar. Additionally, much can be learnt from the radioactive waste disposal experience which will be particularly relevant to the assessments of site performance for CO2 within a regulatory framework, particularly in the methods and approaches to long term site performance assessment.