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ACKNOWLEDGMENTS

This study was performed under the overall guidance of the NCHRP Project Committee SP 20-6. The Committee is chaired by MICHAEL E. TARDIF, Friemund, Jackson and Tardif, LLC. Members are RICHARD A. CHRISTOPHER, HDR Engineering; JOANN GEORGALLIS, California Department of Transportation; WILLIAM E. JAMES, Tennessee Attorney General's Office; PAMELA S. LESLIE, Miami-Dade Expressway Authority; THOMAS G. REEVES, Consultant; MARCELLE SATTIEWHITE JONES, Jacob, Carter and Burgess, Inc.; ROBERT J. SHEA, Pennsylvania Department of Transportation; JAY L. SMITH, Missouri Highway and Transportation Commission; JOHN W. STRAHAN; ROY M. TIPTON, Mississippi Department of Transportation; and THOMAS VIALL, Attorney, Vermont.

JO ANNE ROBINSON provided liaison with the Federal Highway Administration, and CRAWFORD F. JENCKS represents the NCHRP staff.

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