National Academies Press: OpenBook
Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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Improving Operation and Long-Term Safety of the Waste Isolation Pilot Plant

Final Report



Committee on the Waste Isolation Pilot Plant

Board on Radioactive Waste Management

Division on Earth and Life Studies

National Research Council





NATIONAL ACADEMY PRESS
Washington, D.C.

Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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    NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.

    Support for this study was provided by the U.S. Department of Energy under cooperative agreement numbers DE-FC01-94EW54069 and DE-FC01-99EW59049. All opinions, findings, conclusions, and recommendations expressed herein are those of the authors and do not necessarily reflect the views of the Department of Energy.

    International Standard Book Number 0-309-07344-8.

    Additional copies of this report are available from:
    National Academy Press
    2101 Constitution Avenue, N.W.
    Box 285
    Washington, DC 20055
    800-624-6242
    202-334-3313 (in the Washington Metropolitan Area)
    http://www.nap.edu

    Cover: The four drawings on the left represent the natural process of salt encapsulating transuranic waste drums in the WIPP repository. From top to bottom, the chronological sequence is 0 years, 10-15 years, 50 years, and 1,000 and more years (Hansen et al., 1997). Reproduced with permission. The image in the center shows a sample of Permian age salt crystals, about 225 million years old, taken from the WIPP excavations. The picture on the right shows typical scenery in proximity to the WIPP repository.

    Back cover: Picture of three trucks transporting transuranic waste to the WIPP. Source: DOE.

    Copyright 2001 by the National Academy of Sciences. All rights reserved.

    Printed in the United States of America.

Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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    THE NATIONAL ACADEMIES

    National Academy of Sciences
    National Academy of Engineering
    Institute of Medicine
    National Research Council

    The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce M. Alberts is president of the National Academy of Sciences.

    The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. William A. Wulf is president of the National Academy of Engineering.

    The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Kenneth I. Shine is president of the Institute of Medicine.

    The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Bruce M. Alberts and Dr. William A. Wulf are chairman and vice chairman, respectively, of the National Research Council.

Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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    COMMITTEE ON THE WASTE ISOLATION PILOT PLANT

    B. JOHN GARRICK, Chair, Garrick Consulting, Laguna Beach, California

    MARK D. ABKOWITZ, Vanderbilt University, Nashville, Tennessee

    ALFRED W. GRELLA, Grella Consulting, Locust Grove, Virginia

    MICHAEL P. HARDY, Agapito Associates, Inc., Grand Junction, Colorado

    STANLEY KAPLAN, Bayesian Systems Inc., Rockville, Maryland

    HOWARD M. KINGSTON, Duquesne University, Pittsburgh, Pennsylvania

    W. JOHN LEE, Texas A&M University, College Station

    MILTON LEVENSON, Bechtel International, Inc. (retired), Menlo Park, California

    WERNER F. LUTZE, University of New Mexico, Albuquerque

    KIMBERLY OGDEN, University of Arizona, Tucson

    MARTHA R. SCOTT, Texas A&M University, College Station

    JOHN M. SHARP, JR., The University of Texas, Austin

    PAUL G. SHEWMON, Ohio State University (retired), Columbus

    JAMES E. WATSON, JR., University of North Carolina, Chapel Hill

    CHING H. YEW, The University of Texas (retired), Austin

    Liaisons

    DARLEANE C. HOFFMAN, Lawrence Berkeley National Laboratory, Oakland, California (February 1998 to December 1999)

    JAMES O. LECKIE, Stanford University, Stanford, California (January 2000 to December 2000)

    Staff

    BARBARA PASTINA, Study Director

    THOMAS E. KIESS, Study Director (February 1998 to May 2000)

    ANGELA R. TAYLOR, Senior Project Assistant

    Consultants

    LYNDA L. BROTHERS, Sonnenschein Nath & Rosenthal, San Francisco, California

    JOHN T. SMITH, Covington & Burlington, Washington, D.C.

Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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    BOARD ON RADIOACTIVE WASTE MANAGEMENT

    JOHN F. AHEARNE, Chair, Sigma Xi and Duke University, Research Triangle Park, North Carolina

    CHARLES MCCOMBIE, Vice-Chair, Consultant, Gipf-Oberfrick, Switzerland

    ROBERT M. BERNERO, U.S. Nuclear Regulatory Commission (retired), Gaithersburg, Maryland

    ROBERT J. BUDNITZ, Future Resources Associates, Inc., Berkeley, California

    GREGORY R. CHOPPIN, Florida State University, Tallahassee

    RODNEY C. EWING, University of Michigan, Ann Arbor

    JAMES H. JOHNSON, JR., Howard University, Washington, D.C.

    ROGER E. KASPERSON, Stockholm Environment Institute, Stockholm, Sweden

    NIKOLAY P. LAVEROV, Russian Academy of Sciences, Moscow

    JANE C. S. LONG, Mackay School of Mines, University of Nevada, Reno

    ALEXANDER MACLACHLAN, E.I. du Pont de Nemours & Company (retired), Wilmington, Delaware

    WILLIAM A. MILLS, Oak Ridge Associated Universities (retired), Olney, Maryland

    MARTIN J. STEINDLER, Argonne National Laboratory (retired), Downers Grove, Illinois

    ATSUYUKI SUZUKI, University of Tokyo, Japan

    JOHN J. TAYLOR, Electric Power Research Institute (retired), Palo Alto, California

    VICTORIA J. TSCHINKEL, Landers and Parsons, Tallahassee, Florida

    Staff

    KEVIN D. CROWLEY, Director

    MICAH D. LOWENTHAL, Staff Officer

    BARBARA PASTINA, Staff Officer

    GREGORY H. SYMMES, Senior Staff Officer

    JOHN R. WILEY, Senior Staff Officer

    SUSAN B. MOCKLER, Research Associate

    DARLA J. THOMPSON, Senior Project Assistant/Research Assistant

    TONI GREENLEAF, Administrative Associate

    LATRICIA C. BAILEY, Senior Project Assistant

    LAURA D. LLANOS, Senior Project Assistant

    ANGELA R. TAYLOR, Senior Project Assistant

    JAMES YATES, JR., Office Assistant

Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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Acknowledgements

This study could not have been completed without the assistance of many individuals and organizations. The committee especially wishes to acknowledge and thank Inès Triay, Roger Nelson, Chuan-Fu Wu, and Mary Elisabeth “Beth” Bennington of the U.S. Department of Energy (DOE), Carlsbad Field Office. Chuan-Fu and Beth served as liaisons to the committee from the Carlsbad Field Office and ensured that all requests for documents, meetings, and other information were met with a timely response. The committee wishes to thank Kathryn Knowles and Wendell Weart from Sandia National Laboratories, who provided information and several briefings during the course of this study. Matthew Silva (Environmental Evaluation Group), Fred Ferate (U.S. Department of Transportation), Nancy Osgood (U.S. Nuclear Regulatory Commission), Robert “Bobby” Sanchez, and Mona Williams (DOE, National Transportation Program, Albuquerque Operations) were kindly available to committee members for specific clarification. The committee is grateful to all individuals who made presentations or provided information for this study.

Finally, the committee wishes to thank Barbara Pastina, Angela Taylor, and Kevin Crowley, staff of the National Research Council's Board on Radioactive Waste Management, Thomas Kiess, former staff officer and study director, and Elizabeth Ward of Garrick Consulting for great team effort to support this project.

Page viii Cite
Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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List of Reviewers

This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the NRC's Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report:

Ray Chamberlain, Parsons Brinckerhoff, Inc.

Darleane C. Hoffman, Lawrence Berkeley National Laboratory

Leonard F. Konikow, U.S. Geological Survey

James O. Leckie, Stanford University

Harry Mandil, MPR Associates, Inc. (retired)

Michael D. Meyer, Georgia Institute of Technology

Michael O. McWilliams, Stanford University

Michael T. Ryan, Medical University of South Carolina

John J. Taylor, Electric Power Research Institute (retired)

Chris G. Whipple, Environ International Corporation

Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations nor did they see the final draft of the report before its release. The review of this report was overseen by Frank L. Parker, Vanderbilt University. Appointed by the National Research Council, he was responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.

Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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Preface

This study was sponsored by the U.S. Department of Energy (DOE) Carlsbad Field Office, formerly known as Carlsbad Area Office (CAO). To accomplish this project, the National Research Council (NRC) empanelled a 15-member committee on the Waste Isolation Pilot Plant (WIPP). Committee members were chosen for their expertise in relevant technical disciplines such as nuclear engineering, health physics, chemical and environmental engineering, civil and transportation engineering, performance assessment, analytical chemistry, materials science and engineering, plutonium geochemistry, hydrogeology, rock and fracture mechanics, petroleum engineering, and mining engineering. The committee is operated under the auspices of the Board on Radioactive Waste Management of the NRC.

The first committee on the Waste Isolation Pilot Plant was formed in 1978, at the request of the DOE, to provide scientific and technical evaluations of the investigations at the WIPP. That committee functioned as a standing committee until late 1996 at which time it published its final report (NRC, 1996a), The Waste Isolation Pilot Plant, A Potential Solution for the Disposal of Transuranic Waste.1 This was the last report of the committee prior to certification of the site. The committee concluded that “human exposure to radionuclide releases from transuranic waste disposed in the WIPP is likely to be low compared to U.S. and international standards.” The report went on to say, “The only known possibilities of serious release of radionuclides appear to be from poor seals or some form of future human activity that results in intrusion into the repository.” The report recommended that “speculative scenarios of human intrusion should not be used as the sole or primary basis on which to judge the acceptability of the WIPP (and, by extension, any geological repository).”

Following the publication of the 1996 report, this WIPP committee was created to carry out the statement of task reported in Sidebar P.1. The committee has produced two reports to cover the statement of task, an interim report published in April 2000 and this final report. The complete interim report has been reproduced as Appendix A1.


1Transuranic (TRU) waste is waste contaminated with alpha-emitting radionuclides of atomic number greater than 92 and half-lives greater than 20 years in concentrations greater than 100 nanocuries per gram. For more details see Sidebar 1.2 and the glossary.
Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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Sidebar P.1 Statement of Task

The purpose of this study is to identify the limiting technical components of the WIPP program, with a twofold goal of (i) improving the understanding of long-term performance of the repository and (ii) identifying technical options for improvements to the National Transuranic (TRU) Program (i.e., the engineering system that defines TRU waste handling operations that are needed for these wastes to go from their current storage locations to the final repository destination) without compromising safety.

To accomplish this goal, the study will address two major issues:

    1. The first is to identify research activities that would enhance the assessment of long-term repository performance. This study would examine the performance assessment models used to calculate hypothetical long-term releases of radioactivity, and would suggest future scientific and technical work that could reduce uncertainties.

    2. The second is to identify areas for improvement in the TRU waste management system that may increase system throughput, efficiency, cost effectiveness, or safety to workers and the public. This study will examine, among other inputs, the current plans for TRU waste handling, characterization, treatment, packaging, and transportation.


In October 2000, the DOE provided a comprehensive response to the recommendations made in the interim report. The response is reported in Appendix A2. The committee is very encouraged by the quality of the responses and the actions the DOE is taking. Although the responses will not have a full impact on this final publication because of the report's tight schedule, the committee has been able to acknowledge a number of them in this report.

As is the normal practice of the National Academies, committee members do not represent the views of their institutions but form an independent body to author the report using the information gathered together with their collective knowledge and experience. The report reflects a consensus of the committee and has been reviewed in accordance with NRC procedures.

B. John Garrick, Chair
Committee on the Waste Isolation Pilot Plant
April 2001

Page xiii Cite
Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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Contents

EXECUTIVE SUMMARY 1
    Site Performance, 2
    Site Characterization, 3
    The National TRU Program, 4
        Waste Characterization and Packaging, 4
        Waste Transportation, 5
1 INTRODUCTION 7
    Site Performance and Characterization, 15
    The National Transuranic Program, 16
2 REPOSITORY PERFORMANCE CONFIRMATION 20
    Regulatory Requirements for Monitoring, 21
    Site Performance Issues, 22
        Brine Migration and Moisture Access to the Repository, 22
        Gas Generation in the Repository, 23
        Magnesium Oxide Backfill, 25
        Salt Healing and Disturbed Rock Zone Integrity, 26
    Site Characterization Issues, 27
        Geohydrological Characterization of the Rustler Formation, 27
        Oil, Gas, and Mineral Production, 28
        Baseline Radiogenic Analysis of Subsurface Fluids, 31
3 NATIONAL TRANSURANIC WASTE MANAGEMENT PROGRAM 33
    Waste Characterization and Packaging, 33
        Waste Characterization and Packaging Requirements, 33
        Total Inventory of Organic Material in the Repository, 34
    Waste Transportation, 34
        DOE's Communication and Notification Program, 35
        DOE's Emergency Response Program, 37
        Rail as a Transportation Option for Certain TRU Waste, 38
        Gas Generation Safety Analysis for TRUPACT-II Containers, 40
Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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4 SUMMARY 42
    Overarching Finding, 42
    Overarching Recommendation, 42
REFERENCES 44
APPENDIXES
    A1. Interim Report 51
    A2. DOE's Response to the Interim Report 109
    B. Human Intrusion Scenarios 123
    C. Biographical Sketches of Committee Members 128
    D. Glossary 132
    E. Acronyms and Symbols 137
    F. Other Relevant Documents 139
Suggested Citation:"Front Matter." National Research Council. 2001. Improving Operations and Long-Term Safety of the Waste Isolation Pilot Plant: Final Report. Washington, DC: The National Academies Press. doi: 10.17226/10143.
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The Waste Isolation Pilot Plant (WIPP) is a deep underground mined facility for the disposal of transuranic waste resulting from the nation's defense program. Transuranic waste is defined as waste contaminated with transuranic radionuclides with half-life greater than 20 years and activity greater than 100 nanocuries per gram. The waste mainly consists of contaminated protective clothing, rags, old tools and equipment, pieces of dismantled buildings, chemical residues, and scrap materials. The total activity of the waste expected to be disposed at the WIPP is estimated to be approximately 7 million curies, including 12,900 kilograms of plutonium distributed throughout the waste in very dilute form. The WIPP is located near the community of Carlsbad, in southeastern New Mexico. The geological setting is a 600-meter thick, 250 million-year-old saltbed, the Salado Formation, lying 660 meters below the surface.

The National Research Council (NRC) has been providing the U.S. Department of Energy (DOE) scientific and technical evaluations of the WIPP since 1978. The committee's task is twofold: (1) to identify technical issues that can be addressed to enhance confidence in the safe and long-term performance of the repository and (2) to identify opportunities for improving the National Transuranic (TRU) Program for waste management, especially with regard to the safety of workers and the public.

This is the first full NRC report issued following the certification of the facility by the U.S. Environmental Protection Agency (EPA) on May 18, 1998. An interim report was issued by the committee in April 2000 and is reproduced in this report. The main findings and recommendations from the interim report have been incorporated into the body of this report. The overarching finding and recommendation of this report is that the activity that would best enhance confidence in the safe and long-term performance of the repository is to monitor critical performance parameters during the long pre-closure phase of repository operations (35 to possibly 100 years). Indeed, in the first 50 to 100 years the rates of important processes such as salt creep, brine inflow (if any), and microbial activity are predicted to be the highest and will be less significant later. The committee recommends that the results of the on-site monitoring program be used to improve the performance assessment for recertification purposes. These results will determine whether the need for a new performance assessment is warranted. For the National TRU Program, the committee finds that the DOE is implementing many of the recommendations of its interim report. It is important that the DOE continue its efforts to improve the packaging, characterization, and transportation of the transuranic waste.

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