1. Assistant Professor, Dept. of Environmental Engineering, Texas A&M Univ.-Kingsville, MSC 213, Kingsville, TX 78363 (corresponding author). E-mail: lclapp@even.tamuk.edu
2. Professor, Dept. of Civil Engineering, Univ. of Minnesota, 500 Pillsbury Dr., S.E., Minneapolis, MN 55455.
3. Associate Professor, Dept. of Civil Engineering, Univ. of Minnesota, 500 Pillsbury Dr., S.E., Minneapolis, MN 55455.