1. Lecturer, Environmental Science and Studies Program, Spelman College, 350 Spelman Ln., Atlanta, GA 30314.
2. Assistant Professor, Dept. of Civil and Environmental Engineering, Univ. of North Carolina at Charlotte, 9201 University City Blvd., Charlotte, NC 28223 (corresponding author).
3. Associate Professor, Dept. of Civil and Environmental Engineering, Univ. of North Carolina at Charlotte, 9201 University City Blvd., Charlotte, NC 28223.