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August 18, 2000 The Honorable Richard A. Meserve Dear Chairman Meserve: SUBJECT: ACNW VISITS TO NUCLEAR SITES AND INFORMATION EXCHANGES IN THE UNITED KINGDOM AND FRANCE, MAY 15-19, 2000 During the week of May 15-19, 2000, the Advisory Committee on Nuclear Waste (ACNW) visited nuclear waste management sites and attended information exchanges in the United Kingdom (UK) and France. This letter discusses some of our key observations that are relevant to issues of interest to the Commission, such as the critical role of clearing materials resulting from facility decommissioning activities, stakeholder involvement in repository siting, risk-informed regulation, and the management and disposal of low-level radioactive waste. Background On May 15, 2000, in the UK, the Committee visited decommissioning sites and waste processing facilities at Sellafield and the low-level waste (LLW) disposal facility at Drigg, Cumbria, which are operated by British Nuclear Fuels, Ltd. (BNFL). The Committee also met with the leader of the Cumbria County Council(1) and the Council's Environmental Planning Manager. On May 16 and 17, 2000, the Committee participated in a technical information exchange hosted by the UK Environment Agency in London with representatives of a variety of regulatory agencies, licensees, developers, and oversight groups.(2) On May 18, 2000, in France, the Committee participated in an all-day technical information exchange at the Paris headquarters of the National Radioactive Waste Management Agency (ANDRA)(3) with a variety of participants.(4) On May 19, 2000, the Committee visited the ANDRA-operated Centré de l'Aube LLW disposal facility and the site of the future high-level waste (HLW) underground research laboratory (URL) at Bure, Haute-Marne. Attached is a list of the handouts received during the May 15-20, 2000, foreign trip to the UK and France, which are available upon request. Observations on Decommissioning In both the UK and France, an integrated approach to decommissioning includes the clearance of material that meets certain limits for either disposal in conventional waste disposal facilities or unrestricted use. To facilitate their decommissioning activities, both countries have developed a category of radioactive waste called very low-level waste (VLLW) that is not required to be disposed of in LLW sites. The UK allows the practice of freely releasing decontaminated material that was slightly and surficially contaminated after it has passed a series of tests and specifications to show that it meets the release criteria. At Sellafield, the Committee members toured decommissioning activities at the "Windscale Piles." Concrete "rubble" is broken up into a small aggregate size to facilitate monitoring for radioactivity. Material that meets specified limits is "released" and used as fill for repairing roads on BNFL property. Metal materials are bead blasted to provide assurance that the pieces are free of contamination and meet release requirements. Components that have features that could potentially mask contamination (such as riveted pieces) are segregated out and are not released. In France, EdF is following the three-stage International Atomic Energy Agency process for nine shutdown reactor sites. The EdF current strategy is to decommission all nine reactors within 20-25 years to a green field state. France is currently developing methodologies and requirements to differentiate large volumes of reactor decommissioning waste into LLW, VLLW, and non-radioactive material. Waste in the latter two categories would go to conventional disposal sites or be cleared for unrestricted use, respectively. Recommendations The NRC should consider development of regulatory classifications that clearly differentiate between LLW, VLLW, and non-radioactive waste.
Observations on Repository Facility Siting Quasi-governmental agencies in both countries have responsibilities for waste management and repository development: NIREX(5) in the UK and ANDRA in France. In the UK, the intermediate-level waste (ILW)(6) repository siting program is on hold. Stakeholder issues played a significant role in the Cumbria County Council's rejection of the proposed rock characterization facility (RCF) at Sellafield to study potential host rock for an ILW repository.(7) Although the Cumbria County Council is generally supportive of Sellafield operations, the Council expressed a number of technical and policy concerns about the RCF. There was also a need, we were told, for the presentation of technical material in a format that can be understood by the public. In our meetings in London, it was noted that there were problems with understanding the decisionmaking process followed by NIREX, and also there was a need to define processes and the roles of stakeholders. Currently, long-term storage (25-50 years) is envisioned for vitrified HLW and grouted ILW in the UK. The national policy on radioactive waste management and disposal is being re-evaluated. France operates an integrated program for nuclear waste management set up under a law that emphasizes research and specifies processes, organizational responsibilities, and schedules. Early active involvement and agreement of stakeholders, with specific emphasis on local governments and communities, are mandated as an integral part of France's waste program. The law clearly defines the composition and roles of committees and the processes to be followed. The act requires openness in conducting the research program, including consultations (with the communities) before site selection, creation of a National Reviewing Board and a Public Interest Grouping to manage supporting measures, and establishment of Local Information Committees. Starting from 30 potential sites, ANDRA identified three candidate URL sites (two granite, one clay). Currently, work on the clay site is proceeding and the two granite sites have been rejected. ANDRA is looking for a new granite site. In both countries, the ACNW noticed a significant openness in both the government and licensee interactions with the public, principally via elected public representatives such as local councils. They also make extensive use of public tours to communicate with the public. The result seems to be a long-term relationship from which trust and confidence can develop. Recommendation
Observations on Risk-Informed Regulation Probabilistic risk assessments (PRAs) are used extensively in the UK by both developers and regulators, whereas in France the use of PRAs is not generally accepted or required by regulatory policy. A significant concern expressed to us in both countries was the difficulty in communicating to the public highly technical reports and safety assessments. Despite differences in approach, both countries focus much effort on understanding the underlying features, events, and processes that contribute significantly to the safety case for a repository system. The regulatory frameworks in both countries invoke the ALARA (as low as reasonably achievable) concept and require some system of multiple barriers (natural and engineered) to isolate nuclear waste. Risk assessments are conducted in the UK by licensees, applicants, and regulators using probabilistic approaches. These state-of-the-art approaches are similar in some ways to the risk-informed approaches being implemented by the NRC, but the criterion for postclosure compliance is a numerical measure of risk rather than dose.(8) Areas of continuing concern include the transparency of risk assessments, the level of confidence that can be attached to the level of risk, and approaches to broaden stakeholder participation in the risk assessment process. Although there is some use of probabilistic information in risk and safety analyses in France, it is not used in a formalized fashion. The French regulations invoke dose limits as the criteria for compliance.(9) The safety demonstration, which takes into account both qualitative and quantitative analyses, is focused on understanding the system and identifying disruptive events. Performance assessments are deterministic and include both bounding and best estimate calculations. The ANDRA representatives believe that the public will not understand probabilistic approaches to performance assessment. Recommendation
Observations on LLW Disposal Both the UK and France have operating LLW disposal facilities sized to deal with the anticipated wastes for the next 50 or so years. This situation is helping to establish a base of public confidence in waste management that may be carried over into the HLW disposal area. At the Drigg site in the UK, the disposal methodology has evolved over time to the current system of concrete entombments. There is an ongoing development of a postclosure safety assessment with regulatory oversight by the Environment Agency. One of the aspects of the regulatory review is an issue resolution process similar to NRC's issues resolution approach. France is operating a sophisticated LLW disposal facility at Centre de l'Aube. Although, by United States standards, what they are doing is more than is required for similar Class A(10) LLW, France has thereby moved toward gaining public confidence in its waste management program. Finally, we observed at l'Aube the use of a color-coded(11) radiation hazard symbol rather than the "universal" magenta. The l'Aube employees seem to be more sensitive to the distinction. As a result, the signs seem more effective than the single color signs used in the United States. Recommendation
It is clear to the Committee that the UK and France have valuable experience in radioactive waste management for the NRC to consider. This experience relates to many of the Committee's tier one priorities on the regulation of nuclear wastes, including decommissioning, risk-informed practices, and public (and stakeholder) participation.
HANDOUTS RECEIVED DURING THE MAY 15-20, 2000
1. The Council Leader is also chairman of the Sellafield Liaison Committee. 2. Participants included representatives from the UK Environmental Agency; the UK Department of Transport and the Regions; the UK Department of Trade and Industry; the UK Health and Safety Executive; the UK Atomic Energy Agency; the Scottish Environmental Protection Agency; UK NIREX, Ltd.; The Royal Society; the Radioactive Waste Management Advisory Committee; and the Parliamentary Office of Science and Technology. 3. ANDRA is a quasi-governmental agency responsible for radioactive waste disposal programs in France. Decommissioning of nuclear power plants is not included in its scope. 4. Participants included representatives from the Nuclear Installations Safety Directorate, the chief of decommissioning for Electricité de France (EdF), and researchers from the Institute National de Recherche en Informatique et en Automatique and the Université St. Etienne. 5. UK NIREX, Ltd., was originally founded as the "Nuclear Industry Radioactive Waste Executive." 6. ILW in the UK is defined as non-heat-generating radioactive
waste that exceeds 12 GBq/tonne ( 7. Technically, the RCF review was conducted as a planning application by NIREX to the Cumbria County Council, which is required under the UK Town and Country Planning Act of 1990. The adversarial style proceedings, however, delved into a variety of siting and safety issues that might normally be considered in a safety case review (or by a hearing board) in the U.S). 8. In the UK, regulatory guidance specifies an individual risk "target" of 1 X 10-6 for post-institutional control. During institutional control, the dose limit to a representative member of the critical group is 0.3 mSv/yr (30 mrem) for a "source-related dose" and 0.5 mSv/yr (50 mrem) for a "site-related dose." 9. The French regulations limit doses to the public to 1 mSv/yr (100 mrem) for the "normal evolution" (of the repository), with .25 mSv/yr (25 mrem) constraint over the time scale of interest (10,000 yrs). Disruptive events (incidental or accidental scenarios) are considered on a case-by-case basis, according to the probability of the scenario. Doses to workers are limited to 100 mSv (10 rem) over 5 years with a maximum of 50 mSv (5 rem) in 1 year. Transportation worker doses are limited to 20 mSv/yr (2 rem). 10. 10 CFR 6l.55, "Waste Classification." 11. Green for suspect areas, yellow for very low levels, orange for intermediate levels, and red or magenta for high levels. |
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and/or 4 GBq/tonne (
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