Assessment of Future Human Actions at Radioactive Waste Disposal Sites: An international perspective

摘要

For some deep geological disposal systems, the level of confinement provided by the natural and engineered barriers is considered to be so high that the greatest long-term risks associated with waste disposal may arise from the possibility of future human actions breaching the natural and/or engineered barrier systems. Following a Workshop in 1989, the OECD Nuclear Energy Agency established a Working Group on Assessment of Future Human Actions (FHA) a Radioactive Waste Disposal Sites. This Group met four times in the period 1991--1993, and has extensively reviewed approaches to and experience of incorporating the effects of FHA into long-term performance assessments (PAs). The Working Group's report reviews the main issues concerning the treatment of FHA, presents a general framework for the quantitative, consideration of FHA in radioactive waste disposal programmes, and discusses means in reduce the risks associated with FHA. The Working Group concluded that FHA must be considered in PAs, although FHA where the actors were cognizant of the risks could be ignored. Credit can be taken for no more than several hundred years of active site control; additional efforts should therefore be taken to reduce the risks associated with FHA. International agreement on principles for the construction of FHA scenarios would build confidence, as would further discussion concerning regulatory policies for judging risks associated with FHA.