The NEA Organises International Discussions On Regulating
The Long-Term Safety Of Radioactive Waste Disposal
Some sixty specialists met under the aegis of the
OECD Nuclear Energy Agency (OECD/NEA) in Cordoba, Spain, from 20 to 23
January 1997 to discuss progress in the regulation of long-lived radioactive
waste.
Hosted by the Spanish Nuclear Safety
Council (CSN) and the Spanish Radioactive Waste Agency (ENRESA), this
international workshop made possible an in-depth exchange between those
in charge of developing and implementing radioactive waste disposal systems,
and those responsible for regulating these systems to ensure adequate
safety.
In many OECD countries substantial resources
are being devoted to developing radioactive waste disposal systems and
the scientific and practical knowledge necessary to licence them. This
is a particularly challenging task for long-lived radioactive wastes,
such as spent nuclear fuel or high-level waste from the reprocessing of
spent fuel, which need to be isolated from the biosphere for very long
periods of time.
Establishing a sound licensing process
and resolving the associated regulatory issues requires a multi-disciplinary
approach in connection with which radiation and environmental protection,
nuclear safety and waste management specialists play key roles. A mutual
understanding and clear rules must also be established between those proposing
and developing a disposal concept and those who must independently assess
its acceptability from a safety standpoint.
The workshop contributed to a deeper
understanding of the regulatory approaches followed in NEA Member countries
and of the differences which exist in national regulatory systems. In
particular, it was noted that while safety criteria are often expressed
using different units (dose or risk) in different countries, substantive
differences do not exist from a long-term safety standpoint. In this respect,
it was recognised that the main objective is to ensure that future generations
are protected at least to the same level of safety as is acceptable today.
Translating this objective into regulatory terms depends largely on national
cultures and administrative situations. Similarly, the level of proof
to be provided concerning very long-term safety of geologic disposal systems
is a matter of judgement in view of the existence of unavoidable uncertainties
concerning the future. The participation of the public in the decision-making
process is also an important element of national policies, and has a strong
influence on the way the regulatory process will be conducted.
Among the suggestions made by the participants
regarding further work were the drafting of rigorous but practicable regulations;
the treatment of various uncertainties such as the living habits of populations
in the far future and the need to make reasonable assumptions concerning
these habits; and the difficulty of dealing with long-term risk issues
in the context of legal and public perception considerations. The discussions
highlighted that, beyond the solid scientific basis required for safety
assessment, the decision-making process must ultimately rely upon expert
judgement and reasonable assurance considerations, through an open and
transparent process allowing for public participation. The follow-up to
the workshop will be discussed further during the first half of 1997 by
the three sponsoring Committees of the NEA, namely the Committee on Nuclear
Regulatory Activities (CNRA), the Committee on Radiation Protection and
Public Health (CRPPH) and the Radioactive Waste Management Committee (RWMC).
In conclusion, the workshop met its
objectives of promoting deeper understanding of the issues, comparing
the requirements that regulators may set with the scope and depth of analyses
which are currently feasible, and identifying issues and problems which
require additional effort.
