Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 1
THE NATIONAL ACADEMIES Advisers to the Nation on Science, Engineering, and Medicine National Academy of Sciences National Academy of Engineering Institute of Medicine National Research Council Board on Radioactive Waste Management National Research Council March 20, 2002 Dr. Margaret Chu Director Office of Civilian Radioactive Waste Management U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 Dear Dr. Chu: At the request of the U.S. Department of Energy (DOE), the National Research Council1 presents this progress report (see Attachment A) on principles and operational strategies for the staged development of geologic repositories for radioactive high-level waste.2 Geologic repositories for high-level waste, as distinguished from many other waste disposal systems, are unique undertakings in that they are first-of-a-kind, risk-laden, complex, and long-term projects.3 In the presence of such challenges, several international panels on radioactive waste management, including two previous National Research Council committees, recommended adopting a staged development approach. In agreement with this approach, the committee has further refined the concept of staged development and is currently discussing a concept that the committee calls “adaptive staging.” The committee has yet to complete discussion of all the points listed in the statement of task (Attachment C). This progress report confines itself to developing a provisional conceptual framework and a working definition for adaptive staging. The considerations in this report are intentionally generic, that is, they apply to any waste disposal program. The committee also provides some provisional observations, still being discussed, about the U.S. repository program, referred to as the “Yucca Mountain Project.” The final report, planned to be released in the fall of 2002, will address all points of the statement of task. The difficulty of the committee’s task has been magnified by the necessity of completing this progress report at the time of a major policy decision on the suitability of the Yucca Mountain site as a geologic repository for U.S. high-level waste.4 This impending decision has created a 1 This report was prepared by the Committee on Principles and Operational Strategies for Staged Repository Systems, appointed by the National Research Council. Committee members are listed in Attachment D. This report should be referenced as follows: “Principles and Operational Strategies for Staged Repository Systems: Progress Report (National Research Council, 2002).” 2 In this report, the committee uses the term “high-level waste” to include high-level radioactive waste from reprocessing nuclear fuels, spent nuclear fuel, if it is considered to be a waste, and other nuclear materials designated for disposal along with reprocessing waste and spent nuclear fuel. 3 Two previous National Research Council’s reports provide a detailed discussion of the unique features of geologic repositories for high-level waste (NRC, 1990, 2001a). 4 On February 15, 2002 the U.S. President recommended to the Congress the choice of the Yucca Mountain site for the development of a geologic repository for high-level waste. Congress will ultimately decide the site’s suitability. 2101 Constitution Avenue, NW, Washington, DC 20418 Telephone (202) 334 3066 Fax (202) 334 3077 national-academies.org
OCR for page 2
heightened sensitivity to the committee’s statements concerning the Yucca Mountain Project. The committee is not charged to participate in this decision and has not considered the merits of the choice at hand. However, the statement of task does require the committee to examine the concept of staging in principle and then in application to the Yucca Mountain Project. The committee has endeavored to ensure that the results of its deliberations will be valuable and applicable no matter what decision is made on the Yucca Mountain site. The main points of this progress report are summarized as follows. Adaptive staging is defined as a process where the development of a geologic repository for high-level waste is divided into stages that are separated by explicit decision points. Decision points provide the opportunity to evaluate obtained results and to decide how to proceed to the next stage. In fact, any subsequent stage is predicated upon the outcome of previous ones. Decision points also allow for program improvement with respect to, for instance, safety, costs, and schedule. Under adaptive staging, the repository implementer, at each decision point between stages, would: analyze knowledge gathered from previous stages; take into account all relevant options for the next stage, including explicit consideration of reversibility;5,6 evaluate and update the safety case;7 decide on the next stage based on the above set of actions. All of the above actions would incorporate input from stakeholders8 who would also receive feedback on the decisions taken. The committee is still in the process of discussing the role of stakeholders at decision points. In other words, adaptive staging is a cautious, deliberate, decision and management process that involves continuous learning and is also transparent and reversible. The overarching attribute of adaptive staging is that it aims to increase repository safety and to reduce uncertainties through systematic incremental learning. The safety case is at the heart of adaptive staging and drives the identification and choice of options at each stage. Commitment to systematic learning, flexibility, auditability, transparency, integrity, and responsiveness underlie the overarching safety attribute. 5 Reversibility denotes the possibility of reversing one or a series of steps in repository development at any stage of the program. However, if no evidence questioning safety emerges as the program proceeds, decisions become firmer and reversal on technical ground becomes less likely. See section 1 in Attachment A for details. 6 Reversibility is discussed in this report as part of the adaptive staging general concept. This discussion should not be interpreted as a recommendation about the Yucca Mountain Project. 7 A safety case is a collection of arguments, at a given stage of repository development, in support of the long-term safety of the repository. A safety case comprises the findings of a safety assessment and a statement of confidence in these findings. It acknowledges the existence of any unresolved issues and provides guidance for work to resolve these issues in future development stages (NEA, 1999c). DOE adopted a very similar definition of safety case in the framework of the Yucca Mountain Project (DOE, 2000). 8 As defined by DOE, a stakeholder is a person or organization with an interest in or affected by DOE actions. This includes representatives from Federal, state, tribal, or local agencies; members of Congress or state legislatures; unions, educational groups, environmental groups, industrial groups; and members of the general public (DOE, 2002a).
OCR for page 3
The committee is currently investigating the benefits and drawbacks of adaptive staging as they impact programmatic, technical, institutional, regulatory, and societal objectives of a geologic repository. In many of the repository programs that adopted a linear, prescribed, multistep approach there have been delays or failures (NRC, 2001a; page 10). Based upon its own judgment and recommendations from previous panels on waste disposal programs, the committee believes that adaptive staging may address challenges and uncertainties associated with geologic repository development programs more effectively than a linear approach. Adaptive staging brings together technical and societal knowledge gained from implementation of one stage to provide an integrated judgment of the safety case for proceeding to a following stage. The presence of several decision points in the overall repository development plan may improve the likelihood of incorporating knowledge and understanding gained from experience, and opens up the possibility for more effective stakeholder involvement. Two examples of effective stakeholder involvement are briefly illustrated in Attachment B. Although the committee believes that adaptive staging is a promising approach, it also recognizes that adaptive staging is an unproven concept. However, the adaptive staging strategy is consistent with any project management approach that requires simultaneous attention to societal, institutional, and technical concerns. The committee is still analyzing the relationship between adaptive staging and the U.S. approach to repository development. Below are some provisional observations still being analyzed: Not all of the attributes of adaptive staging are currently included in the U.S. repository program. This is in part due to the historical legacy of the U.S. radioactive waste management program, which, for instance, narrowed down the site selection process in a policy decision taken by Congress (NWPAA, 1987). DOE appears to be incorporating a few selected elements of adaptive staging into its program by considering a “modular repository design,” which calls for building the repository and supporting infrastructure, as well as carrying on operations, in phases (see section 3 of Attachment A). According to DOE, this approach increases program flexibility and will provide opportunities for changes in the repository program if significant problems are discovered in the early repository stages. Although this is a staged development approach, this “modular repository design” is proposed to overcome annual budget restrictions, schedule, and regulatory uncertainties rather than to increase opportunities for learning, which would be the prime justification for implementing adaptive staging. Based on this work in progress, the committee believes that emphasizing further the fundamental attributes of adaptive staging could increase program flexibility and responsiveness to new information obtained during successive stages. In its final report, the committee will provide some specific suggestions for incorporating additional elements of adaptive staging into the U.S. repository program. If DOE files a license application for the Yucca Mountain Project, a multi-year period of interaction between DOE and the U.S. Nuclear Regulatory Commission will take place. Therefore, there appears to be time for DOE to develop adaptive staging in its repository program, to reflect on completed stages, and to outline the nature of future stages and decision points.
OCR for page 4
This progress report reflects the consensus of the committee and has been reviewed in accordance with the procedures of the National Research Council. The list of reviewers is given in Attachment E. Sincerely yours, Charles McCombie, Chair David E.Daniel, Vice-Chair Attachment A: Progress report Attachment B: Examples of stakeholder input in repository development Attachment C: Statement of task Attachment D: Committee roster Attachment E: List of reviewers
Representative terms from entire chapter: