1. Assistant Professor, Dept. of Civil and Environmental Engineering, Louisiana State Univ., 3316 N Patrick Taylor Hall, Baton Rouge, LA 70803 (corresponding author).
2. Professor, Dept. of Civil and Environmental Engineering, Univ. of Illinois, 205 N. Mathews Ave., Urbana, IL 61801-2352.
3. Civil Engineer, California Environmental Protection Agency, 1001 I St., Sacramento, CA 95812.