This study and report were prepared by Gene W. Rowe and Bruce Kirstein of the U.S. Nuclear Waste Technical Review Board staff in support of the Board's analysis of issues associated with thermal management, an effort lead by Professor Andrew C. Kadak.

Available as:
Thermal White Paper (823KB)

In this report, the U.S. Nuclear Waste Technical Review Board presents its evaluation of revised DOE estimates of water infiltration at Yucca Mountain. The infiltration estimates were revised because violations of quality assurance procedures were alleged to have been committed by U.S. Geological Survey employees involved in gathering and analyzing infiltration data at Yucca Mountain in the 1990's.

Available as:
Infiltration Report (4129KB)

This report, which is the Board's second report of 2006, contains summaries of Board findings and recommendations contained in the following: letters to the Director of the Office of Civilian Radioactive Waste Management (OCRWM) following Board meetings held in February, May, and September 2006, a letter and enclosures sent to the Director of OCRWM following a Board workshop on deliquescence-induced localized corrosion in September 2006, and testimony presented in May 2006 by the Board's Chairman before the Senate Energy and Natural Resources Committee.

Available as:
Board's second report for 2006 (42KB)

In this report, the Board summarizes its major activities from January 1, 2005, through February 28, 2006. During that period, the Board focused its attention on the Project's efforts to develop post-closure performance estimates for the repository it proposes to construct at Yucca Mountain in Nevada. Correspondence and related materials are included in the appendices to the report along with the Board's strategic plan for fiscal years 2004-2009, its performance plans for fiscal years 2005-2006, and its performance evaluation for 2005.

Available as:
2005 Report to Congress and the Secretary of Energy (63KB)
Appendices A thru D (291 KB)
Appendix E (1,961KB)
Appendix F (879KB)
Appendix G thru H (354KB)
Addendum A thru B (223KB)
Appendix I (224KB)
Entire Report (4,240 KB)

In this letter report to Congress and the Secretary of Energy, the Board presents its views on the status of some important issues related to the technical basis for DOE activities related to the waste management system, the engineered system, the natural system, the repository system, and the assessment of the performance of the systems. The Board also outlines issues that it expects may continue to be of interest in the future.

Available as:
2005 Letter report to Congress and the Secretary of Energy (63KB)

In this report, the Board summarizes its major activities from January 1, 2004, through December 31, 2004. During that period, the Board focused on the Department of Energy's efforts to develop a system for accepting, transporting, and handling high-level radioactive waste and spent nuclear fuel before disposal in the repository proposed for Yucca Mountain. Correspondence and related materials are included in the appendices to the report along with the Board's strategic plan for fiscal years 2004-2009, its performance plans for 2005, and its performance evaluation for 2004.

Available as:
Transmittal Letter, Table of Contents & Report (386KB)
Appendices A thru D (196 KB)
Appendix E (6,312KB)
Appendix F (316KB)
Entire Report (7,033 KB)

This letter and enclosure comprise the Board's second report to Congress and the Secretary of Energy for calendar year 2004. The letter briefly summarizes areas where the Board believes the DOE has made progress, areas requiring attention, and the Board's priorities for the coming year. The enclosure contains a more detailed discussion of these topics.

Available as:
Letter report to Congress and the Secretary of Energy (54KB)

Errata: For both the letter (page 2) and the enclosure (page 5) "incompressible flow" should read "compressible flow".

In this report, the Board summarizes its major activities from January 1, 2003, through December 31, 2003. During that period, the Board continued its evaluation and held meetings on a range of technical and scientific issues, including seismicity, DOE plans for transporting spent nuclear fuel and high-level radioactive waste, the design and operation of facilities at the proposed repository site, performance-confirmation activities, and the potential for localized corrosion. Correspondence and related materials are included in the appendices to the report along with the Board's strategic plan for fiscal years 2004-2009, its performance plans for 2004 and 2005, and its performance evaluation for 2003.

Available as:
Transmittal Letter, Table of Contents & Report (783KB)
Appendices A thru D (150 KB)
Appendix E (5,304KB)
Appendix F (1,149KB)
Appendices G thru J (233KB)
Entire Report (7,044 KB)

This letter and attachments constitutes the Board's second report to Congress and the Secretary of Energy for calendar year 2003. This letter report is composed of letters on localized corrosion sent to the director of the Office of Civilian Radioactive Waste Management (OCRWM) on October 21, 2003, and November 25, 2003.

Available as:
Cover letter, Oct. 21 letter, Nov. 25 letter (433KB)

Technical report supporting Board conclusions in October 21, 2003 letter to the DOE related to the potential for localized corrosion of waste packages during the thermal pulse.

Available as:
Cover letter, Report, Additional Comments (239KB)

This report summarizes the Board's major activities between January 1, 2002, and December 31, 2002. During this period, the Board focused on evaluating the technical basis of the DOE's work related to analyzing a planned repository site at Yucca Mountain in Nevada. Included in an appendix to the report are letters to the DOE related to technical issues identified by the Board as part of its ongoing review in 2002. Also included in the appendices are the Board's strategic plan for fiscal years 2003-2008, its performance plans for FY 2003 and FY 2004, and its performance evaluation for FY 2002.

Available as:
Transmittal Letter, Table of Contents, Report (244KB)
Appendices A thru D (177KB)
Appendix E and F (3.56MB)
Appendices G thru J (254KB)

This report summarizes the Board's major activities between February 1, 2001, and January 31, 2002. During this period, the Board focused on evaluating the technical basis of the DOE's work related to a site recommendation, including the DOE's characterization of the Yucca Mountain site, the DOE's design of the repository and waste package, and the DOE's estimates of how a repository system developed at the site might perform. The report includes a description of activities undertaken by the Board in developing its assessment of the technical basis for the DOE's current performance estimates.

Available as:
Transmittal Letter, Table of Contents, Report (388K)
Appendices A thru D (200K)
Appendix E (1.8M)
Appendix F (764K)
Appendices G thru J (372K)

Letter report summarizing the Board's evaluation of the DOE's technical and scientific investigation of the Yucca Mountain site.

Available as:
Letter report to Congress and the Secretary of Energy (135K)

The Board conducted a workshop on issues related to predicting corrosion behavior for periods of unprecedented duration. The workshop was held on July 19 and 20, 2001, in Arlington, Virginia. The workshop consisted of a panel of 3 Board members and 14 internationally recognized corrosion scientists, 8 of whom were from outside the United States. Following the workshop, most panelists submitted brief papers giving their views on issues related to predicting very long term corrosion. This publication is a compilation of those submissions.

Available as:
Workshop Proceedings (2.4M)

In this report, the Board summarizes its major activities in calendar year 2000. During 2000, the Board identified four priority areas for evaluating the potential repository at Yucca Mountain. The areas are the following:

• meaningful quantification of conservatisms and uncertainties in the DOE's performance assessments
  
• progress in understanding the underlying fundamental processes involved in predicting the rate of waste package corrosion
  
• an evaluation and a comparison of the base-case repository design with a low-temperature design
  
• development of multiple lines of evidence to support the safety case of the proposed repository, the lines of evidence being derived independently of performance assessment and thus not being subject to the limitations of performance assessment.

The report summarizes the Board's views on each priority area. A more detailed discussion of the priorities can be found in letters to the DOE included among the appendices to the report.

Available as:
Transmittal Letter, Table of Contents, Report (201K)
Appendices A thru D (58K)
Appendices E thru F (6M)
Appendices G thru J (92K)

This report, in the form of a letter, presents a brief update of the Board's views on the status of the DOE program.

Available as:
2000 Letter Report - PDF Format

In this report, the Board summarizes its major activities in calendar year 1999. Among the activities discussed in the report is the Board’s 1999 review of the DOE’s viability assessment (VA) of the Yucca Mountain site. The Board’s evaluation of the VA concludes that Yucca Mountain continues to warrant study as the candidate site for a permanent geologic repository and that work should proceed to support a decision on whether to recommend the site for repository development. The Board suggests that the 2001 date for a decision is very ambitious, and focused study should continue on natural and engineered barriers. The Board states that a credible technical basis does not currently exist for the above-boiling repository design included in the VA. The Board recommends evaluation of alternative repository designs, including lower-temperature designs, as a potential way to help reduce the significance of uncertainties related to predictions of repository performance.

Available as:
Transmittal Letter, Table of Contents, Introduction, and Executive Summary (640K)
Report (1.5M)
Appendices (138K)
Appendix H - NWTRB/OCRWM correspondence (6.8M)

In this report, the Board summarizes its major activities during calendar year 1998. The report discusses the research needs identified in the DOE’s recently issued Viability Assessment of the Yucca Mountain site, including plans to gather information on the amount of water that will eventually seep into repository drifts, whether formations under the repository will retard the migration of radionuclides, the flow-and-transport properties of the groundwater that lies approximately 200 meters beneath the repository horizon, and long-term corrosion rates of materials that may be used for the waste packages. The report describes other activities undertaken by the Board in 1998, including a review of the hypothesis that there were hydrothermal upwellings at Yucca Mountain, a workshop held to increase understanding of the range of expert opinion on waste package materials, and a review of the DOE’s draft environmental impact statement for the Yucca Mountain site.

Available as:
Transmittal Letter, Table of Contents, Introduction, and Executive Summary (127K)
Chapter 1 - Board Oversight of DOE's Activities at Yucca Mountain (1.5M)
Chapter 2 - Other Board Activities (89K)
Appendices (107K)
Appendix F - NWTRB/OCRWM correspondence (2.4M)

Report to the U.S. Congress and the Secretary of Energy: Moving Beyond the Viability Assessment.
April 1999.

In its report, the Board offers its views on the DOE’s December 1998 Viability-Assessment of the Yucca Mountain site in Nevada. The Yucca Mountain site is being characterized to determine its suitability as the location of a permanent repository for disposing of spent nuclear fuel and high-level radioactive waste. The Board discusses the need to address key uncertainties that remain about the site, including the performance of the engineered and natural barriers. The Board addresses the DOE’s plans for reducing those uncertainties and suggests that consideration be given to alternative repository designs, including ventilated low-temperature designs that have the potential to reduce uncertainties and simplify the analytical bases for determining site suitably and for licensing. The Board also comments on the DOE’s total system performance assessment, the analytical tool that pulls together information on the performance of the repository system.

Available as:
Moving Beyond the Viability Assessment (36K)

In its report, the Board offers its views on the direction of future scientific and technical research under way and planned by the DOE as part of its program for characterizing a site at Yucca Mountain, Nevada, as a potential repository for spent fuel and high-level radioactive waste. The Board discusses some of the remaining key scientific and technical uncertainties related to performance of a potential repository. The Board’s report addresses some of these uncertainties by examining information about the proposed repository system presented to it in meetings and other technical exchanges. The Board considers and comments on some of the important connections between the site’s natural properties and the current designs for the waste package and other engineered features of the repository.

Available as:
Transmittal Letter, Table of Contents, Executive Summary (104K)
Chapter 1 Overview (329K)
Chapter 2 Unsaturated Zone (101K)
Chapter 3 Engineered Barrier Systems (68K)
Chapter 4 Saturated Zone (176K)
Abbreviations and References (39K)

This series of documents concerns the Board’s review of material related to Mr. Jerry Szymanski’s hypothesis of ongoing, intermittent hydrothermal activity at Yucca Mountain and large earthquake-induced changes in the water table there. The series includes a cover letter, the Board’s review, and the reports of the four consultants the Board contracted with to assist in the review.

Available as:
Cover Letter and Board Review (15 pages) - PDF format (42K)
Consultants Reports (46 pages) - PDF format (5.2Mb)

This report details the Board’s activities in 1997 and covers, among other things, the DOE’s viability assessment, due later this year; underground exploration of the candidate repository site at Yucca Mountain, Nevada; thermal testing underway at the site; what happens when radioactive waste reaches the water table beneath Yucca Mountain; transportation of spent fuel; and the use of expert judgment. The Board makes four recommendations in the report concerning (1) the need for the DOE to begin now to develop alternative design concepts for a repository, (2) the need for the DOE to include estimates of the likely variation in doses for alternative candidate critical groups in its interim performance measure for Yucca Mountain, (3) the need for the DOE to evaluate whether site-specific biosphere data is needed for license application, and (4) the need for the DOE to make full and effective use of formally elicited expert judgment.

Available as:
1997 Findings and Recommendations - PDF format (543K)
1997 Findings and Recommendations - Appendix- PDF format (247K)

This report, in the form of a letter, addresses several key issues, including the DOE’s viability assessment of the Yucca Mountain site, design of the potential repository and waste package, the total system performance assessment, and the enhanced characterization of the repository block (east-west crossing).

Available as:
1997 Report by letter - PDF format (14K)

This report summarizes Board activities during 1996. Chapter 1 provides an overview of the Department of Energy’s high-level nuclear waste management program from the Board’s perspective, including the viability assessment, program status, and progress in exploration and testing. The chapter ends with conclusions and recommendations. Chapter 2 examines the three technical issues-hydrology, radionuclide transport, and performance assessment-and provides conclusions and recommendations. Chapter 3 deals with design , including the concept for underground operations, repository layout and design alternatives, construction planning, thermal loading, and engineered barriers. The Board also makes conclusions and recommendations. Chapter 4 provides an overview of recent Board activities, including the international exchange of information, the Board’s visit to the River Mountains tunnel, and a presentation to the Nuclear Regulatory Commission. Appendices include information on Board members, the organization of the Board’s panels, meetings held in 1996 and scheduled for 1997, the DOE’s responses to previous Board recommendations, a list of Board publications, references for the report, and a glossary of technical terms.

Available as:
1996 Summary Report - PDF format (777K)

This publication was developed from remarks made by Dr. John Cantlon, Chairman of the Nuclear Waste Technical Review Board, at Topseal ’96, an international conference on nuclear waste management and disposal. The meeting was sponsored by the Swedish Nuclear Fuel and Waste Management Company (SKB) and the European Nuclear Society. The publication highlights the Board’s views on the status of the U.S. program for management and disposal of commercial spent nuclear fuel and provides a brief overview of the program’s organization. It summarizes the DOE’s efforts to characterize the Yucca Mountain site and to develop a waste isolation strategy for the site. The publication also outlines legislative and regulatory changes under consideration at that time and the Board’s views on the technical implications of those possible changes.

Available as: Nuclear Waste Management - PDF format (40K)

This report summarizes Board activities during 1995. Chapter 1 provides an overview of the DOE's high-level waste management program, including highlights, current status, legislative issues, milestones, and recommendations. Chapter 2 reports on Board Panel activities and Chapter 3 provides information on new Board members, meetings attended, interactions with Congress and congressional staff, Board presentations to other organizations, interactions with foreign programs, and a review of the Board’s report on interim storage of spent nuclear fuel. Appendices include Board testimony and statements before Congress, Board correspondence of note, and the Department of Energy’s responses to recommendations in previous Board reports.

Available as:
1995 Summary Report - PDF format (587K)
1995 Summary Report Appendix - PDF format (1MB)

This special report caps more than two years of study and analysis by the Board into the issues surrounding the need for interim storage of commercial spent nuclear fuel and the advisability and timing of the development of a federal centralized storage facility. The Board concludes in the report that the DOE’s efforts should remain focused on permanent geologic disposal and the site investigations at Yucca Mountain, Nevada; that planning for a federal centralized spent fuel storage facility and the required transportation infrastructure be begun now, but actual construction delayed until after a site-suitability decision is made about the Yucca Mountain site; that storage should be developed incrementally; that limited, emergency backup storage capacity be authorized at an existing nuclear facility; and that, if the Yucca Mountain site proves unacceptable for repository development, other potential sites for both centralized storage and disposal be considered.

Available as:
Disposal and Storage of Spent Nuclear Fuel - PDF format (217K)

This report, in the form of a letter, addresses the DOE’s progress in underground exploration with the tunnel boring machine, advances in the development of a waste isolation strategy, new work on engineered barriers, and progress being made in performance assessment.

Available as: 1995 Report by letter - PDF format (16K)

This report summarizes Board activities during 1994. It covers aspects of the DOE’s Program Approach, their emerging waste isolation strategy, and their transportation program. It also explores the Board’s views on minimum exploratory requirements and thermal-loading issues. The report<->focuses a chapter on the lessons that have been learned in site assessment from projects around the world. Another chapter deals with volcanism and resolution of difficult issues. The Board also details its observations from its visit to Japan and the Japanese nuclear waste disposal program. Findings and recommendations in the report centered around structural geology and geoengineering, hydrogeology and geochemistry, the engineered barrier system, and risk and performance analysis.

Available as:
1994 Summary Report - PDF format (659K)
1994 Summary Report Appendix - PDF format (1.1MB)

This report summarizes Board activities primarily during 1993. It reviews the nuclear waste disposal programs of Belgium, France, and the United Kingdom; elaborates on the Board’s understanding of the radiation protection standards being reviewed by the National Academy of Sciences; and, using “future climates” as an example, examines the DOE’s approach to “resolving difficult issues.” Recommendations center on the use of a systems approach in all of OCRWM’s programs, prioritization of site-suitability activities, appropriate use of total system performance assessment and expert judgment, and the dynamics of the Yucca Mountain ecosystem.

Available as:
1993 Summary Report - PDF format (605K)
1993 Summary Report Appendix - PDF format (624K)

This report is issued in letter format due to impending legislative hearings on the DOE’s fiscal year 1995 budget and new funding mechanisms sought by the Secretary of Energy. The 8-page report (ninth in the NWTRB series) restates a recommendation made in the Board’s Special Report, that an independent review of the OCRWM’s management and organizational structure be initiated as soon as possible. Also, it adds two additional recommendations: ensure sufficient and reliable funding for site characterization and performance assessment, whether the program budget remains level or is increased, and build on the Secretary of Energy’s new public involvement initiative by expanding current efforts to integrate the views of the various stakeholders during the decision-making process-not afterward.

Available as:
Letter Report - PDF format (245K)

This report (eighth in the NWTRB series) focuses on the exploratory studies facility at Yucca Mountain, Nevada: the conceptual design, planned exploration and testing, and excavation plans and schedules. In addition to a number of detailed recommendations, the Board makes three general recommendations. First, the DOE should develop a comprehensive strategy that integrates exploration and testing priorities with the design and excavation approach for the exploratory facility. Second, underground thermal testing should be resumed as soon as possible. Third, the DOE should establish a geoengineering board with expertise in the engineering, construction, and management of large underground projects.

Available as:
Underground Exploration and Testing - PDF format (160K)

The Board’s seventh report provides a nontechnical approach for those not familiar with the details of the DOE’s high-level nuclear waste management program. It highlights three important policy issues: the program is driven by unrealistic deadlines, there is no integrated waste management plan, and program management needs improvement. The Board makes three specific recommendations: amend the current schedule to include realistic intermediate milestones; develop a comprehensive, well-integrated plan for the overall management of all spent nuclear fuel and high-level defense waste from generation to disposal; and implement an independent evaluation of the Office of Civilian Radioactive Waste Management’s (OCRWM) organization and management. These recommendations should be implemented without slowing the progress of site-characterization activities at Yucca Mountain.

Available as:
Special Report - PDF format (70K)

The sixth report begins by summarizing recent Board activities, congressional testimony, changes in Board makeup, and the Little Skull Mountain earthquake. Chapter 2 details panel activities and offers seven technical recommendations on the dangers of a schedule-driven program; the need for top-level systems studies; the impact of defense high-level waste; the use of high capacity, self-shielded waste package designs; and the need for prioritization among the numerous studies included in the site-characterization plans. In Chapter 3, the Board offers candid insights to the high-level waste management program in five countries, specifically those areas that might be applicable to the U.S. program, including program size and cost, utility responsibilities, repository construction schedules, and alternative approaches to licensing. Appendix F provides background on the Finnish and Swiss programs.

Available as:
Sixth Report - PDF format (528K)
Sixth Report Appendix - PDF format (1.1M)

The Board’s fifth report focuses on the cross-cutting issue of thermal loading. It explores thermal-loading strategies (U.S. and others) and the technical issues and uncertainties related to thermal loading. It also details the Board’s position on the implications of thermal loading for the U.S. radioactive waste management system. Also included are updates on Board and panel activities during the reporting period. The report offers fifteen recommendations to the DOE on the following subjects: ESF and repository design enhancements, repository sealing, seismic vulnerabilities (vibratory ground motion and fault displacement), the DOE approach to the engineered barrier system, and transportation and systems program status.

Available as:
Fifth Report - PDF format (572K)
Fifth Report Appendix - PDF format (275K)

The fourth report provides update on the Board’s activities and explores in depth the following areas: exploratory studies facility (ESF) construction; test prioritization; rock mechanics; tectonic features and processes; volcanism; hydrogeology and geochemistry in the unsaturated zone; the engineered barrier system; regulations promulgated by the Environmental Protection Agency, the Nuclear Regulatory Commission (NRC), and the DOE; the DOE performance assessment program; and quality assurance in the Yucca Mountain project. Ten recommendations are made across these diverse subject areas. Chapter 3 offers insights from the Board’s visit with officials from the Canadian nuclear power and spent fuel disposal programs. Background on the Canadian program is in Appendix D.

Available as:
Fourth Report - PDF format (425K)
Fourth Report Appendix - PDF format (310K)

The third report briefly describes recent Board activities and congressional testimony. Substantive chapters cover exploratory shaft facility alternatives, repository design, risk-benefit analysis, waste package plans and funding, spent fuel corrosion performance, transportation and systems, environmental program concerns, more on the DOE task force studies on risk and performance assessment, federal quality assurance requirements for the repository program, and the measurement, modeling, and application of radionuclide sorption data. Fifteen specific recommendations are made to the DOE. Background information on the German and Swedish nuclear waste disposal programs is included in Appendix D.

Available as:
Third Report - PDF format (361K)
Third Report Appendix - PDF format (388K)

The Board’s second report begins with the background and framework for repository development and then opens areas of inquiry, making 20 specific recommendations concerning tectonic features and processes, geoengineering considerations, the engineered barrier system, transportation and systems, environmental and public health issues, and risk and performance analysis. The report also offers concluding perspectives on DOE progress, the state of Nevada’s role, the project’s regulatory framework, the nuclear waste negotiator, other oversight agencies, and the Board’s future plans.

Available as:
Second Report - PDF format (450K)
Second Report Appendix - PDF format (213K)

The first report sets the stage for the Board’s evaluation of the Department of Energy’s (DOE) program to manage the disposal of the nation’s spent fuel and high-level waste. The report outlines briefly the legislative history of the nation’s spent fuel and high-level waste management program including its legal and regulatory requirements. The Board’s evolution is described, along with its protocol, panel breakdown, and reporting requirements. The report identifies major issues based on the Board’s panel breakdown, and highlights five cross-cutting issues.

Available as:
First Report - PDF Format (394K)