Conceptual Models of Flow and Transport in the Fractured Vadose Zone

399 Pages·2001·13.77 MB·English

by  National Research Council, Panel on Conceptual Models of Flow and Transport in the Fractured Vadose Zone, U.S. National Committee for Rock Mechanics, Board on Earth Sciences and Resources

CONCEPTUAL MODELS
OF FLOW AND TRANSPORT IN THE
FRACTURED VADOSE ZONE
Panel on Conceptual Models of Flow and Transport
in the Fractured Vadose Zone
U.S. National Committee for Rock Mechanics
Board on Earth Sciences and Resources
Commission on Geosciences, Environment, and Resources
National Research Council
NATIONAL ACADEMY PRESS
Washington, D.C.
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.
This study was supported by the U.S. Nuclear Regulatory Commission, award number NRC-04-96-
078, and the U.S. Department of Energy, DE-FG08-97NV12056. The opinions, findings, conclu-
sions, and recommendations expressed herein are those of the authors and do not necessarily reflect
the view of the Nuclear Regulatory Commission or the U.S. Department of Energy.
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Cover: Illustrations courtesy of David A. Feary (photographs from Yucca Mountain and Busted
Butte), and Peters, R. R., and E. A. Klavetter, 1988, a continuum model for water movement in an
unsaturated fractured rock mass, Water Resources Research 24(3): 416-430, copyright by American
Geophysical Union (for schematic figure showing fluid in fractures).
Copyright 2001 by the National Academy of Sciences. All rights reserved.
Printed in the United States of America
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PANEL ON CONCEPTUAL MODELS OF FLOW AND TRANSPORT
IN THE FRACTURED VADOSE ZONE
PAUL A. HSIEH, Chair, U.S. Geological Survey, Menlo Park, California
JEAN M. BAHR, University of Wisconsin, Madison
THOMAS W. DOE, Golder Associates, Inc., Redmond, Washington
ALAN L. FLINT, U.S. Geological Survey, Sacramento, California
GLENDON GEE, Battelle Pacific Northwest Laboratory, Richland,
Washington
LYNN W. GELHAR, Massachusetts Institute of Technology, Cambridge
D. KIP SOLOMON, University of Utah, Salt Lake City
MARTINUS VAN GENUCHTEN, U.S. Salinity Laboratory, Riverside,
California
STEPHEN W. WHEATCRAFT, University of Nevada, Reno
NRC Staff
DAVID A. FEARY, Senior Program Officer (beginning 3/2000)
THOMAS M. USSELMAN, Senior Program Officer (through 2/2000)
JENNIFER T. ESTEP, Administrative Associate
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U. S. NATIONAL COMMITTEE FOR ROCK MECHANICS
HERBERT H. EINSTEIN, Chair, Massachusetts Institute of Technology,
Cambridge
RONALD P. STEIGER, Vice-Chair, Exxon Production Research Co., Houston,
Texas
CATHERINE T. AIMONE-MARTIN, New Mexico Institute of Mining and
Technology, Socorro
JAAK J.K. DAEMEN, University of Nevada, Reno
EMMANUEL DETOURNAY, University of Minnesota, Minneapolis
JOANNE T. FREDRICH, Sandia National Laboratories, Albuquerque, New
Mexico
RICHARD E. GOODMAN, University of California, Berkeley
PAUL A. HSIEH, U.S. Geological Survey, Menlo Park, California
JAMES E. MONSEES, Parsons Brinckerhoff, Inc., Orange, California
LAURA J. PYRAK-NOLTE, Purdue University, West Lafayette, Indiana
NRC Staff
DAVID A. FEARY, Senior Program Officer
JENNIFER T. ESTEP, Administrative Associate
vi
BOARD ON EARTH SCIENCES AND RESOURCES
RAYMOND JEANLOZ, Chair, University of California, Berkeley
JOHN J. AMORUSO, Amoruso Petroleum Company, Houston, Texas
PAUL BARTON, JR., U.S. Geological Survey (emeritus), Reston, Virginia
BARBARA L. DUTROW, Louisiana State University, Baton Rouge
ADAM M. DZIEWONSKI, Harvard University, Cambridge, Massachusetts
RICHARD S. FISKE, Smithsonian Institution, Washington, D.C.
JAMES M. FUNK, Shell Continental Companies, Houston, Texas (retired)
WILLIAM L. GRAF, Arizona State University, Tempe
SUSAN M. KIDWELL, University of Chicago, Illinois
SUSAN KIEFFER, Kieffer & Woo, Inc., Palgrave, Ontario, Canada
PAMELA E. LUTTRELL, Dallas, Texas
ALEXANDRA NAVROTSKY, University of California, Davis
DIANNE R. NIELSON, Utah Department of Environmental Quality,
Salt Lake City
JONATHAN PRICE, Nevada Bureau of Mines & Geology, Reno
NRC Staff
ANTHONY R. DE SOUZA, Director
TAMARA L. DICKINSON, Senior Program Officer
DAVID A. FEARY, Senior Program Officer
ANNE M. LINN, Senior Program Officer
LISA M. VANDEMARK, Program Officer
JENNIFER T. ESTEP, Administrative Associate
VERNA J. BOWEN, Administrative Assistant
REBECCA E. SHAPACK, Research Assistant
TERESIA K. WILMORE, Project Assistant
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COMMISSION ON GEOSCIENCES,
ENVIRONMENT, AND RESOURCES
GEORGE M. HORNBERGER, Chair, University of Virginia, Charlottesville
RICHARD A. CONWAY, Union Carbide Corporation (retired), South
Charleston, West Virginia
LYNN GOLDMAN, Johns Hopkins School of Hygiene and Public Health,
Baltimore, Maryland
THOMAS E. GRAEDEL, Yale University, New Haven, Connecticut
THOMAS J. GRAFF, Environmental Defense Fund, Oakland, California
EUGENIA KALNAY, University of Maryland, College Park
DEBRA KNOPMAN, Progressive Policy Institute, Washington, D.C.
JOHN B. MOONEY, JR., J. Brad Mooney Associates, Ltd., Arlington, Virginia
HUGH C. MORRIS, El Dorado Gold Corporation, Vancouver, British Columbia
H. RONALD PULLIAM, University of Georgia, Athens
MILTON RUSSELL, University of Tennessee (retired), Knoxville
ROBERT J. SERAFIN, National Center for Atmospheric Research,
Boulder, Colorado
ANDREW R. SOLOW, Woods Hole Oceanographic Institution, Massachusetts
E-AN ZEN, University of Maryland, College Park
NRC Staff
ROBERT M. HAMILTON, Executive Director
GREGORY H. SYMMES, Associate Executive Director
JEANETTE SPOON, Administrative and Financial Officer
CHRISTINE HENDERSON, Scientific Reports Officer
SANDI FITZPATRICK, Administrative Associate
viii
Preface
The purpose of this study is to describe the processes through which concep-
tual models of flow and transport in the fractured vadose zone are developed,
tested, refined, and reviewed. The Panel convened a two-day workshop in March
1999, during which a large group of specialists from the hydrogeologic, geochem-
ical, soil science, and related fields discussed the current state of knowledge,
lessons learned from field investigations, and needs for future research. A series
of invited presentations provided the basis for much of the discussion at this
workshop. Individually authored papers based on these presentations are pre-
sented as Chapters 2-11 in the second part of this volume.
The Panel was charged with preparing a consensus report on the develop-
ment and testing of conceptual models for fluid flow and transport in the frac-
tured vadose zone. The Panel’s conclusions and recommendations were based in
large part on the workshop presentations and discussions. This report is intended
to describe the present status of conceptual model building in the fractured va-
dose zone; to provide guidance to regulatory agencies on the review process for
conceptual models developed for site licensing; to compile knowledge and expe-
riences from related disciplines so that technical communities can benefit from
advances in related fields; and to identify future research needed to advance the
technical basis for developing and evaluating vadose zone conceptual models.
In its consideration of transport in the vadose zone, the Panel focused on the
application of environmental tracers (such as tritium and chlorine-36) because
they provide integrated responses that are difficult to determine by point mea-
surements of fluid potential or moisture content. The Panel briefly reviewed
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