1. Project Engineer, Black & Veatch, 18310 Montgomery Village Ave., Suite 500, Gaithersburg, MD 20879 (corresponding author).
2. Deceased; formerly, Professor, Dept. of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA 24061.
3. Professor, Dept. of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA 24061.
4. Professor, Dept. of Agricultural and Applied Economics, Virginia Tech, Blacksburg, VA 24061.
5. Assistant Professor, Civil and Environmental Engineering, San Jose Univ., San Jose, CA 95192.