LEE W. ABRAMSON, a vice president of Hatch Mott MacDonald, Inc., is the author of the Handbook on Ground Control and Improvement (Wiley). THOMAS S. LEE is a senior professional associate with Parsons Brinckerhoff Quade & Douglas, Inc. SUNIL SHARMA is a professor of civil engineering at the University of Idaho in Moscow, Idaho. GLENN M. BOYCE is a senior professional associate with Parsons Brinckerhoff Quade & Douglas, Inc.