1. Professor, Dept. of Civil Engineering, 205 Cobleigh Hall, Montana State Univ., Bozeman, MT 59717 (corresponding author).
2. Christopher Consultants, 210 Boxelder Lane, Roswell, GA 30076.
3. Senior Engineer, TenCate Geosynthetics, 365 South Holland Dr., Pendergrass, GA 30567.
4. Senior Engineer, BBG Bauberatung Geokunststoffe GmbH & Co. KG, P. O. Box 3025, 32332 Espelkamp-Fiestel, Germany.